F2FS.

Bumps [cross-platform-actions/action](https://github.com/cross-platform-actions/action) from 0.23.0 to 0.24.0.
- [Release notes](https://github.com/cross-platform-actions/action/releases)
- [Changelog](https://github.com/cross-platform-actions/action/blob/master/changelog.md)
- [Commits](https://github.com/cross-platform-actions/action/compare/v0.23.0...v0.24.0)

---
updated-dependencies:
- dependency-name: cross-platform-actions/action
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/bsd.sh

@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -euo pipefail
 
 echo 'set -euo pipefail' > test.sh
 

.github/workflows/bsd.yml

@@ -1,31 +0,0 @@
-name: BSD
-
-on:
-  workflow_dispatch:
-
-jobs:
-  test:
-    runs-on: macos-12
-
-    steps:
-    - uses: actions/checkout@v4
-      with:
-        lfs: 'true'
-
-    - name: Set up
-      uses: actions/setup-go@v5
-      with:
-        go-version: stable
-
-    - name: Build
-      run: .github/workflows/bsd.sh
-
-    - name: Test
-      uses: cross-platform-actions/action@v0.22.0
-      with:
-        operating_system: freebsd
-        version: '13.2'
-        memory: 8G
-        shell: bash
-        sync_files: runner-to-vm
-        run: source test.sh

.github/workflows/cpu.yml

@@ -1,56 +0,0 @@
-name: CPUs
-
-on:
-  workflow_dispatch:
-
-jobs:
-  test-386:
-    runs-on: ubuntu-latest
-
-    steps:
-    - uses: actions/checkout@v4
-      with:
-        lfs: 'true'
-
-    - name: Set up
-      uses: actions/setup-go@v5
-      with:
-        go-version: stable
-
-    - name: Test
-      run: GOARCH=386 go test -v -short ./...
-
-  test-arm:
-    runs-on: ubuntu-latest
-
-    steps:
-    - uses: actions/checkout@v4
-      with:
-        lfs: 'true'
-
-    - name: Set up
-      uses: actions/setup-go@v5
-      with:
-        go-version: stable
-
-    - name: Install QEMU
-      uses: docker/setup-qemu-action@v3
-
-    - name: Test
-      run: GOARCH=arm64 go test -v -short ./...
-
-  test-m1:
-    runs-on: macos-14
-
-    steps:
-      - uses: actions/checkout@v4
-        with:
-          lfs: 'true'
-
-      - name: Set up
-        uses: actions/setup-go@v5
-        with:
-          go-version: stable
-
-      - name: Test
-        run: go test -v ./...

.github/workflows/cross.sh

@@ -17,7 +17,9 @@ echo aix           ; GOOS=aix       GOARCH=ppc64 go build .
 echo js            ; GOOS=js        GOARCH=wasm  go build .
 echo wasip1        ; GOOS=wasip1    GOARCH=wasm  go build .
 echo darwin-flock  ; GOOS=darwin    GOARCH=amd64 go build -tags sqlite3_flock .
+echo darwin-noshm  ; GOOS=darwin    GOARCH=amd64 go build -tags sqlite3_noshm .
 echo darwin-nosys  ; GOOS=darwin    GOARCH=amd64 go build -tags sqlite3_nosys .
+echo linux-noshm   ; GOOS=linux     GOARCH=amd64 go build -tags sqlite3_noshm .
 echo linux-nosys   ; GOOS=linux     GOARCH=amd64 go build -tags sqlite3_nosys .
 echo windows-nosys ; GOOS=windows   GOARCH=amd64 go build -tags sqlite3_nosys .
 echo freebsd-nosys ; GOOS=freebsd   GOARCH=amd64 go build -tags sqlite3_nosys .

.github/workflows/cross.yml

@@ -10,8 +10,7 @@ jobs:
     steps:
     - uses: actions/checkout@v4
 
-    - name: Set up
-      uses: actions/setup-go@v5
+    - uses: actions/setup-go@v5
       with:
         go-version: stable
 

.github/workflows/go.yml

@@ -1,63 +0,0 @@
-name: Go
-
-on:
-  push:
-    branches: [ "main" ]
-  pull_request:
-    branches: [ "main" ]
-  workflow_dispatch:
-
-jobs:
-  test:
-    strategy:
-      matrix:
-        os: [macos-latest, ubuntu-latest, windows-latest]
-    runs-on: ${{ matrix.os }}
-
-    steps:
-    - uses: actions/checkout@v4
-      with:
-        lfs: 'true'
-
-    - name: Set up
-      uses: actions/setup-go@v5
-      with:
-        go-version: stable
-
-    - name: Format
-      run: gofmt -s -w . && git diff --exit-code
-      if: matrix.os != 'windows-latest'
-
-    - name: Tidy
-      run: go mod tidy && git diff --exit-code
-
-    - name: Download
-      run: go mod download
-
-    - name: Verify
-      run: go mod verify
-
-    - name: Vet
-      run: go vet ./...
-
-    - name: Build
-      run: go build -v ./...
-
-    - name: Test
-      run: go test -v ./...
-
-    - name: Test no locks
-      run: go test -v -tags sqlite3_nosys ./tests -run TestDB_nolock
-
-    - name: Test BSD locks
-      run: go test -v -tags sqlite3_flock ./...
-      if: matrix.os == 'macos-latest'
-
-    - name: Coverage report
-      uses: ncruces/go-coverage-report@v0
-      with:
-        chart: true
-        amend: true
-      if: |
-        github.event_name == 'push' &&
-        matrix.os == 'ubuntu-latest'

.github/workflows/repro.sh

@@ -2,22 +2,22 @@
 set -euo pipefail
 
 if [[ "$OSTYPE" == "linux"* ]]; then
-  WASI_SDK="https://github.com/WebAssembly/wasi-sdk/releases/download/wasi-sdk-21/wasi-sdk-21.0-linux.tar.gz"
-  BINARYEN="https://github.com/WebAssembly/binaryen/releases/download/version_116/binaryen-version_116-x86_64-linux.tar.gz"
+  WASI_SDK="https://github.com/WebAssembly/wasi-sdk/releases/download/wasi-sdk-22/wasi-sdk-22.0-linux.tar.gz"
+  BINARYEN="https://github.com/WebAssembly/binaryen/releases/download/version_117/binaryen-version_117-x86_64-linux.tar.gz"
 elif [[ "$OSTYPE" == "darwin"* ]]; then
-  WASI_SDK="https://github.com/WebAssembly/wasi-sdk/releases/download/wasi-sdk-21/wasi-sdk-21.0-macos.tar.gz"
-  BINARYEN="https://github.com/WebAssembly/binaryen/releases/download/version_116/binaryen-version_116-x86_64-macos.tar.gz"
+  WASI_SDK="https://github.com/WebAssembly/wasi-sdk/releases/download/wasi-sdk-22/wasi-sdk-22.0-macos.tar.gz"
+  BINARYEN="https://github.com/WebAssembly/binaryen/releases/download/version_117/binaryen-version_117-x86_64-macos.tar.gz"
 elif [[ "$OSTYPE" == "msys" || "$OSTYPE" == "cygwin" ]]; then
-  WASI_SDK="https://github.com/WebAssembly/wasi-sdk/releases/download/wasi-sdk-21/wasi-sdk-21.0.m-mingw.tar.gz"
-  BINARYEN="https://github.com/WebAssembly/binaryen/releases/download/version_116/binaryen-version_116-x86_64-windows.tar.gz"
+  WASI_SDK="https://github.com/WebAssembly/wasi-sdk/releases/download/wasi-sdk-22/wasi-sdk-22.0.m-mingw.tar.gz"
+  BINARYEN="https://github.com/WebAssembly/binaryen/releases/download/version_117/binaryen-version_117-x86_64-windows.tar.gz"
 fi
 
 # Download tools
-mkdir -p tools
+mkdir -p tools/
 [ -d "tools/wasi-sdk"* ]         || curl -#L "$WASI_SDK" | tar xzC tools &
 [ -d "tools/binaryen-version"* ] || curl -#L "$BINARYEN" | tar xzC tools &
 wait
 
 sqlite3/download.sh   # Download SQLite
-embed/build.sh        # Build WASM
+embed/build.sh        # Build Wasm
 git diff --exit-code  # Check diffs

.github/workflows/repro.yml

@@ -15,8 +15,7 @@ jobs:
       with:
         lfs: 'true'
 
-    - name: Set up
-      uses: actions/setup-go@v5
+    - uses: actions/setup-go@v5
       with:
         go-version: stable
 

.github/workflows/test.yml

@@ -0,0 +1,133 @@
+name: Test
+
+on:
+  push:
+    branches: [ "main" ]
+  pull_request:
+    branches: [ "main" ]
+  workflow_dispatch:
+
+jobs:
+  test:
+    strategy:
+      matrix:
+        os: [macos-latest, ubuntu-latest, windows-latest]
+    runs-on: ${{ matrix.os }}
+
+    steps:
+    - uses: actions/checkout@v4
+      with: { lfs: 'true' }
+
+    - uses: actions/setup-go@v5
+      with: { go-version: stable }
+
+    - name: Format
+      run: gofmt -s -w . && git diff --exit-code
+      if: matrix.os != 'windows-latest'
+
+    - name: Tidy
+      run: go mod tidy && git diff --exit-code
+
+    - name: Download
+      run: go mod download
+
+    - name: Verify
+      run: go mod verify
+
+    - name: Vet
+      run: go vet ./...
+
+    - name: Build
+      run: go build -v ./...
+
+    - name: Test
+      run: go test -v ./...
+
+    - name: Test BSD locks
+      run: go test -v -tags sqlite3_flock ./...
+      if: matrix.os == 'macos-latest'
+
+    - name: Test no shared memory
+      run: go test -v -tags sqlite3_noshm ./...
+      if: matrix.os == 'ubuntu-latest'
+
+    - name: Test no locks
+      run: go test -v -tags sqlite3_nosys ./tests -run TestDB_nolock
+
+    - name: Test GORM
+      run: gormlite/test.sh
+
+    - uses: ncruces/go-coverage-report@v0
+      with:
+        chart: true
+        amend: true
+      if: |
+        github.event_name == 'push' &&
+        matrix.os == 'ubuntu-latest'
+
+  test-bsd:
+    runs-on: ubuntu-latest
+    needs: test
+
+    steps:
+    - uses: actions/checkout@v4
+      with: { lfs: 'true' }
+
+    - uses: actions/setup-go@v5
+      with: { go-version: stable }
+
+    - name: Build
+      run: .github/workflows/bsd.sh
+
+    - name: Test
+      uses: cross-platform-actions/action@v0.24.0
+      with:
+        operating_system: freebsd
+        version: '14.0'
+        shell: bash
+        run: source test.sh
+        sync_files: runner-to-vm
+
+  test-m1:
+    runs-on: macos-14
+    needs: test
+
+    steps:
+    - uses: actions/checkout@v4
+      with: { lfs: 'true' }
+
+    - uses: actions/setup-go@v5
+      with: { go-version: stable }
+
+    - name: Test
+      run: go test -v ./...
+
+  test-386:
+    runs-on: ubuntu-latest
+    needs: test
+
+    steps:
+    - uses: actions/checkout@v4
+      with: { lfs: 'true' }
+
+    - uses: actions/setup-go@v5
+      with: { go-version: stable }
+
+    - name: Test
+      run: GOARCH=386 go test -v -short ./...
+
+  test-arm:
+    runs-on: ubuntu-latest
+    needs: test
+
+    steps:
+    - uses: actions/checkout@v4
+      with: { lfs: 'true' }
+
+    - uses: actions/setup-go@v5
+      with: { go-version: stable }
+
+    - uses: docker/setup-qemu-action@v3
+
+    - name: Test
+      run: GOARCH=arm64 go test -v -short ./...

README.md

@@ -8,7 +8,7 @@ Go module `github.com/ncruces/go-sqlite3` is `cgo`-free [SQLite](https://sqlite.
 It provides a [`database/sql`](https://pkg.go.dev/database/sql) compatible driver,
 as well as direct access to most of the [C SQLite API](https://sqlite.org/cintro.html).
 
-It wraps a [WASM](https://webassembly.org/) build of SQLite, and uses [wazero](https://wazero.io/) as the runtime.\
+It wraps a [Wasm](https://webassembly.org/) build of SQLite, and uses [wazero](https://wazero.io/) as the runtime.\
 Go, wazero and [`x/sys`](https://pkg.go.dev/golang.org/x/sys) are the _only_ runtime dependencies.
 
 ### Packages
@@ -48,6 +48,8 @@ Go, wazero and [`x/sys`](https://pkg.go.dev/golang.org/x/sys) are the _only_ run
   provides [statistics](https://www.oreilly.com/library/view/sql-in-a/9780596155322/ch04s02.html) functions.
 - [`github.com/ncruces/go-sqlite3/ext/unicode`](https://pkg.go.dev/github.com/ncruces/go-sqlite3/ext/unicode)
   provides [Unicode aware](https://sqlite.org/src/dir/ext/icu) functions.
+- [`github.com/ncruces/go-sqlite3/ext/zorder`](https://pkg.go.dev/github.com/ncruces/go-sqlite3/ext/zorder)
+  maps multidimensional data to one dimension.
 - [`github.com/ncruces/go-sqlite3/vfs/memdb`](https://pkg.go.dev/github.com/ncruces/go-sqlite3/vfs/memdb)
   implements an in-memory VFS.
 - [`github.com/ncruces/go-sqlite3/vfs/readervfs`](https://pkg.go.dev/github.com/ncruces/go-sqlite3/vfs/readervfs)
@@ -70,50 +72,10 @@ Go, wazero and [`x/sys`](https://pkg.go.dev/golang.org/x/sys) are the _only_ run
 ### Caveats
 
 This module replaces the SQLite [OS Interface](https://sqlite.org/vfs.html)
-(aka VFS) with a [pure Go](vfs/) implementation.
-This has benefits, but also comes with some drawbacks.
+(aka VFS) with a [pure Go](vfs/) implementation,
+which has advantages and disadvantages.
 
-#### Write-Ahead Logging
-
-Because WASM does not support shared memory,
-[WAL](https://sqlite.org/wal.html) support is [limited](https://sqlite.org/wal.html#noshm).
-
-To work around this limitation, SQLite is [patched](sqlite3/locking_mode.patch)
-to always use `EXCLUSIVE` locking mode for WAL databases.
-
-Because connection pooling is incompatible with `EXCLUSIVE` locking mode,
-to use the [`database/sql`](https://pkg.go.dev/database/sql) driver
-with WAL mode databases you should disable connection pooling by calling
-[`db.SetMaxOpenConns(1)`](https://pkg.go.dev/database/sql#DB.SetMaxOpenConns).
-
-#### File Locking
-
-POSIX advisory locks, which SQLite uses on Unix, are
-[broken by design](https://sqlite.org/src/artifact/2e8b12?ln=1073-1161).
-
-On Linux, macOS and illumos, this module uses
-[OFD locks](https://www.gnu.org/software/libc/manual/html_node/Open-File-Description-Locks.html)
-to synchronize access to database files.
-OFD locks are fully compatible with POSIX advisory locks.
-
-On BSD Unixes, this module uses
-[BSD locks](https://man.freebsd.org/cgi/man.cgi?query=flock&sektion=2).
-On BSD Unixes, BSD locks are fully compatible with POSIX advisory locks.
-
-On Windows, this module uses `LockFileEx` and `UnlockFileEx`,
-like SQLite.
-
-On all other platforms, file locking is not supported, and you must use
-[`nolock=1`](https://sqlite.org/uri.html#urinolock)
-(or [`immutable=1`](https://sqlite.org/uri.html#uriimmutable))
-to open database files.
-
-To use the [`database/sql`](https://pkg.go.dev/database/sql) driver
-with `nolock=1` you must disable connection pooling by calling
-[`db.SetMaxOpenConns(1)`](https://pkg.go.dev/database/sql#DB.SetMaxOpenConns).
-
-You can use [`vfs.SupportsFileLocking`](https://pkg.go.dev/github.com/ncruces/go-sqlite3/vfs#SupportsFileLocking)
-to check if your platform supports file locking.
+Read more about the Go VFS design [here](vfs/README.md).
 
 ### Testing
 
@@ -121,7 +83,7 @@ This project aims for [high test coverage](https://github.com/ncruces/go-sqlite3
 It also benefits greatly from [SQLite's](https://sqlite.org/testing.html) and
 [wazero's](https://tetrate.io/blog/introducing-wazero-from-tetrate/#:~:text=Rock%2Dsolid%20test%20approach) thorough testing.
 
-The pure Go VFS is tested by running SQLite's
+The Go VFS is tested by running SQLite's
 [mptest](https://github.com/sqlite/sqlite/blob/master/mptest/mptest.c)
 on Linux, macOS, Windows and FreeBSD.
 
@@ -130,7 +92,7 @@ on Linux, macOS, Windows and FreeBSD.
 Perfomance of the [`database/sql`](https://pkg.go.dev/database/sql) driver is
 [competitive](https://github.com/cvilsmeier/go-sqlite-bench) with alternatives.
 
-The WASM and VFS layers are also tested by running SQLite's
+The Wasm and VFS layers are also tested by running SQLite's
 [speedtest1](https://github.com/sqlite/sqlite/blob/master/test/speedtest1.c).
 
 ### Alternatives

config.go

@@ -82,7 +82,7 @@ func (c *Conn) SetAuthorizer(cb func(action AuthorizerActionCode, name3rd, name4
 
 }
 
-func authorizerCallback(ctx context.Context, mod api.Module, pDB uint32, action AuthorizerActionCode, zName3rd, zName4th, zSchema, zNameInner uint32) AuthorizerReturnCode {
+func authorizerCallback(ctx context.Context, mod api.Module, pDB uint32, action AuthorizerActionCode, zName3rd, zName4th, zSchema, zNameInner uint32) (rc AuthorizerReturnCode) {
 	if c, ok := ctx.Value(connKey{}).(*Conn); ok && c.handle == pDB && c.authorizer != nil {
 		var name3rd, name4th, schema, nameInner string
 		if zName3rd != 0 {
@@ -97,7 +97,68 @@ func authorizerCallback(ctx context.Context, mod api.Module, pDB uint32, action
 		if zNameInner != 0 {
 			nameInner = util.ReadString(mod, zNameInner, _MAX_NAME)
 		}
-		return c.authorizer(action, name3rd, name4th, schema, nameInner)
+		rc = c.authorizer(action, name3rd, name4th, schema, nameInner)
 	}
-	return AUTH_OK
+	return rc
+}
+
+// WalCheckpoint checkpoints a WAL database.
+//
+// https://sqlite.org/c3ref/wal_checkpoint_v2.html
+func (c *Conn) WalCheckpoint(schema string, mode CheckpointMode) (nLog, nCkpt int, err error) {
+	defer c.arena.mark()()
+	nLogPtr := c.arena.new(ptrlen)
+	nCkptPtr := c.arena.new(ptrlen)
+	schemaPtr := c.arena.string(schema)
+	r := c.call("sqlite3_wal_checkpoint_v2",
+		uint64(c.handle), uint64(schemaPtr), uint64(mode),
+		uint64(nLogPtr), uint64(nCkptPtr))
+	nLog = int(int32(util.ReadUint32(c.mod, nLogPtr)))
+	nCkpt = int(int32(util.ReadUint32(c.mod, nCkptPtr)))
+	return nLog, nCkpt, c.error(r)
+}
+
+// WalAutoCheckpoint configures WAL auto-checkpoints.
+//
+// https://sqlite.org/c3ref/wal_autocheckpoint.html
+func (c *Conn) WalAutoCheckpoint(pages int) error {
+	r := c.call("sqlite3_wal_autocheckpoint", uint64(c.handle), uint64(pages))
+	return c.error(r)
+}
+
+// WalHook registers a callback function to be invoked
+// each time data is committed to a database in WAL mode.
+//
+// https://sqlite.org/c3ref/wal_hook.html
+func (c *Conn) WalHook(cb func(db *Conn, schema string, pages int) error) {
+	var enable uint64
+	if cb != nil {
+		enable = 1
+	}
+	c.call("sqlite3_wal_hook_go", uint64(c.handle), enable)
+	c.wal = cb
+}
+
+func walCallback(ctx context.Context, mod api.Module, _, pDB, zSchema uint32, pages int32) (rc uint32) {
+	if c, ok := ctx.Value(connKey{}).(*Conn); ok && c.handle == pDB && c.wal != nil {
+		schema := util.ReadString(mod, zSchema, _MAX_NAME)
+		err := c.wal(c, schema, int(pages))
+		_, rc = errorCode(err, ERROR)
+	}
+	return rc
+}
+
+// AutoVacuumPages registers a autovacuum compaction amount callback.
+//
+// https://sqlite.org/c3ref/autovacuum_pages.html
+func (c *Conn) AutoVacuumPages(cb func(schema string, dbPages, freePages, bytesPerPage uint) uint) error {
+	funcPtr := util.AddHandle(c.ctx, cb)
+	r := c.call("sqlite3_autovacuum_pages_go", uint64(c.handle), uint64(funcPtr))
+	return c.error(r)
+}
+
+func autoVacuumCallback(ctx context.Context, mod api.Module, pApp, zSchema, nDbPage, nFreePage, nBytePerPage uint32) uint32 {
+	fn := util.GetHandle(ctx, pApp).(func(schema string, dbPages, freePages, bytesPerPage uint) uint)
+	schema := util.ReadString(mod, zSchema, _MAX_NAME)
+	return uint32(fn(schema, uint(nDbPage), uint(nFreePage), uint(nBytePerPage)))
 }

conn.go

@@ -29,6 +29,7 @@ type Conn struct {
 	update     func(AuthorizerActionCode, string, string, int64)
 	commit     func() bool
 	rollback   func()
+	wal        func(*Conn, string, int) error
 	arena      arena
 
 	handle uint32
@@ -281,6 +282,12 @@ func (c *Conn) ReleaseMemory() error {
 	return c.error(r)
 }
 
+// GetInterrupt gets the context set with [Conn.SetInterrupt],
+// or nil if none was set.
+func (c *Conn) GetInterrupt() context.Context {
+	return c.interrupt
+}
+
 // SetInterrupt interrupts a long-running query when a context is done.
 //
 // Subsequent uses of the connection will return [INTERRUPT]
@@ -325,13 +332,13 @@ func (c *Conn) checkInterrupt() {
 	}
 }
 
-func progressCallback(ctx context.Context, mod api.Module, pDB uint32) uint32 {
+func progressCallback(ctx context.Context, mod api.Module, pDB uint32) (interrupt uint32) {
 	if c, ok := ctx.Value(connKey{}).(*Conn); ok && c.handle == pDB && c.commit != nil {
 		if c.interrupt != nil && c.interrupt.Err() != nil {
-			return 1
+			interrupt = 1
 		}
 	}
-	return 0
+	return interrupt
 }
 
 // BusyTimeout sets a busy timeout.
@@ -359,28 +366,13 @@ func (c *Conn) BusyHandler(cb func(count int) (retry bool)) error {
 	return nil
 }
 
-func busyCallback(ctx context.Context, mod api.Module, pDB, count uint32) uint32 {
+func busyCallback(ctx context.Context, mod api.Module, pDB uint32, count int32) (retry uint32) {
 	if c, ok := ctx.Value(connKey{}).(*Conn); ok && c.handle == pDB && c.busy != nil {
-		if retry := c.busy(int(count)); retry {
-			return 1
+		if c.busy(int(count)) {
+			retry = 1
 		}
 	}
-	return 0
-}
-
-// Deprecated: executes a PRAGMA statement and returns results.
-func (c *Conn) Pragma(str string) ([]string, error) {
-	stmt, _, err := c.Prepare(`PRAGMA ` + str)
-	if err != nil {
-		return nil, err
-	}
-	defer stmt.Close()
-
-	var pragmas []string
-	for stmt.Step() {
-		pragmas = append(pragmas, stmt.ColumnText(0))
-	}
-	return pragmas, stmt.Close()
+	return retry
 }
 
 func (c *Conn) error(rc uint64, sql ...string) error {

const.go

@@ -256,41 +256,41 @@ const (
 type AuthorizerActionCode uint32
 
 const (
-	/************************************************ 3rd ************ 4th ***********/
-	CREATE_INDEX        AuthorizerActionCode = 1  /* Index Name      Table Name      */
-	CREATE_TABLE        AuthorizerActionCode = 2  /* Table Name      NULL            */
-	CREATE_TEMP_INDEX   AuthorizerActionCode = 3  /* Index Name      Table Name      */
-	CREATE_TEMP_TABLE   AuthorizerActionCode = 4  /* Table Name      NULL            */
-	CREATE_TEMP_TRIGGER AuthorizerActionCode = 5  /* Trigger Name    Table Name      */
-	CREATE_TEMP_VIEW    AuthorizerActionCode = 6  /* View Name       NULL            */
-	CREATE_TRIGGER      AuthorizerActionCode = 7  /* Trigger Name    Table Name      */
-	CREATE_VIEW         AuthorizerActionCode = 8  /* View Name       NULL            */
-	DELETE              AuthorizerActionCode = 9  /* Table Name      NULL            */
-	DROP_INDEX          AuthorizerActionCode = 10 /* Index Name      Table Name      */
-	DROP_TABLE          AuthorizerActionCode = 11 /* Table Name      NULL            */
-	DROP_TEMP_INDEX     AuthorizerActionCode = 12 /* Index Name      Table Name      */
-	DROP_TEMP_TABLE     AuthorizerActionCode = 13 /* Table Name      NULL            */
-	DROP_TEMP_TRIGGER   AuthorizerActionCode = 14 /* Trigger Name    Table Name      */
-	DROP_TEMP_VIEW      AuthorizerActionCode = 15 /* View Name       NULL            */
-	DROP_TRIGGER        AuthorizerActionCode = 16 /* Trigger Name    Table Name      */
-	DROP_VIEW           AuthorizerActionCode = 17 /* View Name       NULL            */
-	INSERT              AuthorizerActionCode = 18 /* Table Name      NULL            */
-	PRAGMA              AuthorizerActionCode = 19 /* Pragma Name     1st arg or NULL */
-	READ                AuthorizerActionCode = 20 /* Table Name      Column Name     */
-	SELECT              AuthorizerActionCode = 21 /* NULL            NULL            */
-	TRANSACTION         AuthorizerActionCode = 22 /* Operation       NULL            */
-	UPDATE              AuthorizerActionCode = 23 /* Table Name      Column Name     */
-	ATTACH              AuthorizerActionCode = 24 /* Filename        NULL            */
-	DETACH              AuthorizerActionCode = 25 /* Database Name   NULL            */
-	ALTER_TABLE         AuthorizerActionCode = 26 /* Database Name   Table Name      */
-	REINDEX             AuthorizerActionCode = 27 /* Index Name      NULL            */
-	ANALYZE             AuthorizerActionCode = 28 /* Table Name      NULL            */
-	CREATE_VTABLE       AuthorizerActionCode = 29 /* Table Name      Module Name     */
-	DROP_VTABLE         AuthorizerActionCode = 30 /* Table Name      Module Name     */
-	FUNCTION            AuthorizerActionCode = 31 /* NULL            Function Name   */
-	SAVEPOINT           AuthorizerActionCode = 32 /* Operation       Savepoint Name  */
-	COPY                AuthorizerActionCode = 0  /* No longer used */
-	RECURSIVE           AuthorizerActionCode = 33 /* NULL            NULL            */
+	/***************************************************** 3rd ************ 4th ***********/
+	AUTH_CREATE_INDEX        AuthorizerActionCode = 1  /* Index Name      Table Name      */
+	AUTH_CREATE_TABLE        AuthorizerActionCode = 2  /* Table Name      NULL            */
+	AUTH_CREATE_TEMP_INDEX   AuthorizerActionCode = 3  /* Index Name      Table Name      */
+	AUTH_CREATE_TEMP_TABLE   AuthorizerActionCode = 4  /* Table Name      NULL            */
+	AUTH_CREATE_TEMP_TRIGGER AuthorizerActionCode = 5  /* Trigger Name    Table Name      */
+	AUTH_CREATE_TEMP_VIEW    AuthorizerActionCode = 6  /* View Name       NULL            */
+	AUTH_CREATE_TRIGGER      AuthorizerActionCode = 7  /* Trigger Name    Table Name      */
+	AUTH_CREATE_VIEW         AuthorizerActionCode = 8  /* View Name       NULL            */
+	AUTH_DELETE              AuthorizerActionCode = 9  /* Table Name      NULL            */
+	AUTH_DROP_INDEX          AuthorizerActionCode = 10 /* Index Name      Table Name      */
+	AUTH_DROP_TABLE          AuthorizerActionCode = 11 /* Table Name      NULL            */
+	AUTH_DROP_TEMP_INDEX     AuthorizerActionCode = 12 /* Index Name      Table Name      */
+	AUTH_DROP_TEMP_TABLE     AuthorizerActionCode = 13 /* Table Name      NULL            */
+	AUTH_DROP_TEMP_TRIGGER   AuthorizerActionCode = 14 /* Trigger Name    Table Name      */
+	AUTH_DROP_TEMP_VIEW      AuthorizerActionCode = 15 /* View Name       NULL            */
+	AUTH_DROP_TRIGGER        AuthorizerActionCode = 16 /* Trigger Name    Table Name      */
+	AUTH_DROP_VIEW           AuthorizerActionCode = 17 /* View Name       NULL            */
+	AUTH_INSERT              AuthorizerActionCode = 18 /* Table Name      NULL            */
+	AUTH_PRAGMA              AuthorizerActionCode = 19 /* Pragma Name     1st arg or NULL */
+	AUTH_READ                AuthorizerActionCode = 20 /* Table Name      Column Name     */
+	AUTH_SELECT              AuthorizerActionCode = 21 /* NULL            NULL            */
+	AUTH_TRANSACTION         AuthorizerActionCode = 22 /* Operation       NULL            */
+	AUTH_UPDATE              AuthorizerActionCode = 23 /* Table Name      Column Name     */
+	AUTH_ATTACH              AuthorizerActionCode = 24 /* Filename        NULL            */
+	AUTH_DETACH              AuthorizerActionCode = 25 /* Database Name   NULL            */
+	AUTH_ALTER_TABLE         AuthorizerActionCode = 26 /* Database Name   Table Name      */
+	AUTH_REINDEX             AuthorizerActionCode = 27 /* Index Name      NULL            */
+	AUTH_ANALYZE             AuthorizerActionCode = 28 /* Table Name      NULL            */
+	AUTH_CREATE_VTABLE       AuthorizerActionCode = 29 /* Table Name      Module Name     */
+	AUTH_DROP_VTABLE         AuthorizerActionCode = 30 /* Table Name      Module Name     */
+	AUTH_FUNCTION            AuthorizerActionCode = 31 /* NULL            Function Name   */
+	AUTH_SAVEPOINT           AuthorizerActionCode = 32 /* Operation       Savepoint Name  */
+	AUTH_COPY                AuthorizerActionCode = 0  /* No longer used */
+	AUTH_RECURSIVE           AuthorizerActionCode = 33 /* NULL            NULL            */
 )
 
 // AuthorizerReturnCode are the integer codes
@@ -305,6 +305,18 @@ const (
 	AUTH_IGNORE AuthorizerReturnCode = 2 /* Don't allow access, but don't generate an error */
 )
 
+// CheckpointMode are all the checkpoint mode values.
+//
+// https://sqlite.org/c3ref/c_checkpoint_full.html
+type CheckpointMode uint32
+
+const (
+	CHECKPOINT_PASSIVE  CheckpointMode = 0 /* Do as much as possible w/o blocking */
+	CHECKPOINT_FULL     CheckpointMode = 1 /* Wait for writers, then checkpoint */
+	CHECKPOINT_RESTART  CheckpointMode = 2 /* Like FULL but wait for readers */
+	CHECKPOINT_TRUNCATE CheckpointMode = 3 /* Like RESTART but also truncate WAL */
+)
+
 // TxnState are the allowed return values from [Conn.TxnState].
 //
 // https://sqlite.org/c3ref/c_txn_none.html

driver/driver_test.go

@@ -153,7 +153,7 @@ func Test_BeginTx(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	_, err = tx1.Exec(`CREATE TABLE IF NOT EXISTS test (col)`)
+	_, err = tx1.Exec(`CREATE TABLE test (col)`)
 	if err == nil {
 		t.Error("want error")
 	}
@@ -310,7 +310,7 @@ func Test_time(t *testing.T) {
 
 			twosday := time.Date(2022, 2, 22, 22, 22, 22, 0, time.UTC)
 
-			_, err = db.Exec(`CREATE TABLE IF NOT EXISTS test (at DATETIME)`)
+			_, err = db.Exec(`CREATE TABLE test (at DATETIME)`)
 			if err != nil {
 				t.Fatal(err)
 			}

driver/json_test.go

@@ -18,7 +18,7 @@ func Example_json() {
 	defer db.Close()
 
 	_, err = db.Exec(`
-		CREATE TABLE IF NOT EXISTS orders (
+		CREATE TABLE orders (
 			cart_id INTEGER PRIMARY KEY,
 			user_id INTEGER NOT NULL,
 			cart    TEXT

driver/savepoint_test.go

@@ -16,7 +16,7 @@ func ExampleSavepoint() {
 	}
 	defer db.Close()
 
-	_, err = db.Exec(`CREATE TABLE IF NOT EXISTS users (id INT, name VARCHAR(10))`)
+	_, err = db.Exec(`CREATE TABLE users (id INT, name VARCHAR(10))`)
 	if err != nil {
 		log.Fatal(err)
 	}

embed/README.md

@@ -1,11 +1,11 @@
-# Embeddable WASM build of SQLite
+# Embeddable Wasm build of SQLite
 
-This folder includes an embeddable WASM build of SQLite 3.45.1 for use with
+This folder includes an embeddable Wasm build of SQLite 3.45.3 for use with
 [`github.com/ncruces/go-sqlite3`](https://pkg.go.dev/github.com/ncruces/go-sqlite3).
 
 The following optional features are compiled in:
 - [math functions](https://sqlite.org/lang_mathfunc.html)
-- [FTS3/4](https://sqlite.org/fts3.html)/[5](https://sqlite.org/fts5.html)
+- [FTS5](https://sqlite.org/fts5.html)
 - [JSON](https://sqlite.org/json1.html)
 - [R*Tree](https://sqlite.org/rtree.html)
 - [GeoPoly](https://sqlite.org/geopoly.html)

embed/build.sh

@@ -4,8 +4,8 @@ set -euo pipefail
 cd -P -- "$(dirname -- "$0")"
 
 ROOT=../
-BINARYEN="$ROOT/tools/binaryen-version_116/bin"
-WASI_SDK="$ROOT/tools/wasi-sdk-21.0/bin"
+BINARYEN="$ROOT/tools/binaryen-version_117/bin"
+WASI_SDK="$ROOT/tools/wasi-sdk-22.0/bin"
 
 "$WASI_SDK/clang" --target=wasm32-wasi -std=c17 -flto -g0 -O2 \
   -Wall -Wextra -Wno-unused-parameter \

embed/exports.txt

@@ -1,7 +1,9 @@
+aligned_alloc
 free
 malloc
 malloc_destructor
 sqlite3_anycollseq_init
+sqlite3_autovacuum_pages_go
 sqlite3_backup_finish
 sqlite3_backup_init
 sqlite3_backup_pagecount
@@ -114,4 +116,7 @@ sqlite3_vtab_in_first
 sqlite3_vtab_in_next
 sqlite3_vtab_nochange
 sqlite3_vtab_on_conflict
-sqlite3_vtab_rhs_value
+sqlite3_vtab_rhs_value
+sqlite3_wal_autocheckpoint
+sqlite3_wal_checkpoint_v2
+sqlite3_wal_hook_go

example_test.go

@@ -16,7 +16,7 @@ func Example() {
 		log.Fatal(err)
 	}
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS users (id INT, name VARCHAR(10))`)
+	err = db.Exec(`CREATE TABLE users (id INT, name VARCHAR(10))`)
 	if err != nil {
 		log.Fatal(err)
 	}

ext/blobio/blob.go

@@ -128,12 +128,12 @@ func getAuxBlob(ctx sqlite3.Context, arg []sqlite3.Value, write bool) (*sqlite3.
 	return ctx.Conn().OpenBlob(db, table, column, row, write)
 }
 
-func setAuxBlob(ctx sqlite3.Context, blob *sqlite3.Blob, writer bool) {
+func setAuxBlob(ctx sqlite3.Context, blob *sqlite3.Blob, open bool) {
 	// This ensures the blob is closed if db, table, column or write change.
 	ctx.SetAuxData(0, blob) // db
 	ctx.SetAuxData(1, blob) // table
 	ctx.SetAuxData(2, blob) // column
-	if writer {
+	if open {
 		ctx.SetAuxData(4, blob) // write
 	}
 }

ext/blobio/blob_test.go

@@ -27,7 +27,7 @@ func Example() {
 	}
 	defer db.Close()
 
-	_, err = db.Exec(`CREATE TABLE IF NOT EXISTS test (col)`)
+	_, err = db.Exec(`CREATE TABLE test (col)`)
 	if err != nil {
 		log.Fatal(err)
 	}
@@ -79,8 +79,8 @@ func Test_readblob(t *testing.T) {
 	}
 
 	err = db.Exec(`
-		CREATE TABLE IF NOT EXISTS test1 (col);
-		CREATE TABLE IF NOT EXISTS test2 (col);
+		CREATE TABLE test1 (col);
+		CREATE TABLE test2 (col);
 		INSERT INTO test1 VALUES (x'cafe');
 		INSERT INTO test2 VALUES (x'babe');
 	`)
@@ -139,8 +139,8 @@ func Test_openblob(t *testing.T) {
 	}
 
 	err = db.Exec(`
-		CREATE TABLE IF NOT EXISTS test1 (col);
-		CREATE TABLE IF NOT EXISTS test2 (col);
+		CREATE TABLE test1 (col);
+		CREATE TABLE test2 (col);
 		INSERT INTO test1 VALUES (x'cafe');
 		INSERT INTO test2 VALUES (x'babe');
 	`)

ext/csv/csv_test.go

@@ -20,7 +20,7 @@ func Example() {
 	csv.Register(db)
 
 	err = db.Exec(`
-		CREATE VIRTUAL TABLE IF NOT EXISTS eurofxref USING csv(
+		CREATE VIRTUAL TABLE eurofxref USING csv(
 			filename = 'testdata/eurofxref.csv',
 			header   = YES,
 			columns  = 42,

ext/fileio/coro.go

@@ -0,0 +1,68 @@
+package fileio
+
+import (
+	"fmt"
+
+	"github.com/ncruces/go-sqlite3/internal/util"
+)
+
+// Adapted from: https://research.swtch.com/coro
+
+const errCoroCanceled = util.ErrorString("coroutine canceled")
+
+func coroNew[In, Out any](f func(In, func(Out) In) Out) (resume func(In) (Out, bool), cancel func()) {
+	type msg[T any] struct {
+		panic any
+		val   T
+	}
+
+	cin := make(chan msg[In])
+	cout := make(chan msg[Out])
+	running := true
+	resume = func(in In) (out Out, ok bool) {
+		if !running {
+			return
+		}
+		cin <- msg[In]{val: in}
+		m := <-cout
+		if m.panic != nil {
+			panic(m.panic)
+		}
+		return m.val, running
+	}
+	cancel = func() {
+		if !running {
+			return
+		}
+		e := fmt.Errorf("%w", errCoroCanceled)
+		cin <- msg[In]{panic: e}
+		m := <-cout
+		if m.panic != nil && m.panic != e {
+			panic(m.panic)
+		}
+	}
+	yield := func(out Out) In {
+		cout <- msg[Out]{val: out}
+		m := <-cin
+		if m.panic != nil {
+			panic(m.panic)
+		}
+		return m.val
+	}
+	go func() {
+		defer func() {
+			if running {
+				running = false
+				cout <- msg[Out]{panic: recover()}
+			}
+		}()
+		var out Out
+		m := <-cin
+		if m.panic == nil {
+			out = f(m.val, yield)
+		}
+		running = false
+		cout <- msg[Out]{val: out}
+	}()
+	return resume, cancel
+}

ext/fileio/fileio.go

@@ -22,7 +22,7 @@ func Register(db *sqlite3.Conn) {
 // and the table-valued function fsdir;
 // fsys will be used to read files and list directories.
 func RegisterFS(db *sqlite3.Conn, fsys fs.FS) {
-	db.CreateFunction("lsmode", 1, 0, lsmode)
+	db.CreateFunction("lsmode", 1, sqlite3.DETERMINISTIC, lsmode)
 	db.CreateFunction("readfile", 1, sqlite3.DIRECTONLY, readfile(fsys))
 	if fsys == nil {
 		db.CreateFunction("writefile", -1, sqlite3.DIRECTONLY, writefile)

ext/fileio/fsdir.go

@@ -53,12 +53,12 @@ func (d fsdir) Open() (sqlite3.VTabCursor, error) {
 
 type cursor struct {
 	fsdir
-	curr  entry
-	next  chan entry
-	done  chan struct{}
-	base  string
-	rowID int64
-	eof   bool
+	base   string
+	resume func(struct{}) (entry, bool)
+	cancel func()
+	curr   entry
+	eof    bool
+	rowID  int64
 }
 
 type entry struct {
@@ -68,12 +68,8 @@ type entry struct {
 }
 
 func (c *cursor) Close() error {
-	if c.done != nil {
-		close(c.done)
-		s := <-c.next
-		c.done = nil
-		c.next = nil
-		return s.err
+	if c.cancel != nil {
+		c.cancel()
 	}
 	return nil
 }
@@ -96,16 +92,25 @@ func (c *cursor) Filter(idxNum int, idxStr string, arg ...sqlite3.Value) error {
 		c.base = base
 	}
 
-	c.rowID = 0
+	c.resume, c.cancel = coroNew(func(_ struct{}, yield func(entry) struct{}) entry {
+		walkDir := func(path string, d fs.DirEntry, err error) error {
+			yield(entry{d, err, path})
+			return nil
+		}
+		if c.fsys != nil {
+			fs.WalkDir(c.fsys, root, walkDir)
+		} else {
+			filepath.WalkDir(root, walkDir)
+		}
+		return entry{}
+	})
 	c.eof = false
-	c.next = make(chan entry)
-	c.done = make(chan struct{})
-	go c.WalkDir(root)
+	c.rowID = 0
 	return c.Next()
 }
 
 func (c *cursor) Next() error {
-	curr, ok := <-c.next
+	curr, ok := c.resume(struct{}{})
 	c.curr = curr
 	c.eof = !ok
 	c.rowID++
@@ -165,22 +170,3 @@ func (c *cursor) Column(ctx *sqlite3.Context, n int) error {
 	}
 	return nil
 }
-
-func (c *cursor) WalkDir(path string) {
-	defer close(c.next)
-
-	if c.fsys != nil {
-		fs.WalkDir(c.fsys, path, c.WalkDirFunc)
-	} else {
-		filepath.WalkDir(path, c.WalkDirFunc)
-	}
-}
-
-func (c *cursor) WalkDirFunc(path string, d fs.DirEntry, err error) error {
-	select {
-	case <-c.done:
-		return fs.SkipAll
-	case c.next <- entry{d, err, path}:
-		return nil
-	}
-}

ext/fileio/fsdir_test.go

@@ -28,7 +28,7 @@ func Test_fsdir(t *testing.T) {
 			}
 			defer db.Close()
 
-			rows, err := db.Query(`SELECT * FROM fsdir('.', '.') LIMIT 4`)
+			rows, err := db.Query(`SELECT * FROM fsdir('.', '.')`)
 			if err != nil {
 				t.Fatal(err)
 			}

ext/stats/stats_test.go

@@ -20,7 +20,7 @@ func TestRegister_variance(t *testing.T) {
 
 	stats.Register(db)
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS data (x)`)
+	err = db.Exec(`CREATE TABLE data (x)`)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -92,7 +92,7 @@ func TestRegister_covariance(t *testing.T) {
 
 	stats.Register(db)
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS data (y, x)`)
+	err = db.Exec(`CREATE TABLE data (y, x)`)
 	if err != nil {
 		t.Fatal(err)
 	}

ext/unicode/unicode_test.go

@@ -81,7 +81,7 @@ func TestRegister_collation(t *testing.T) {
 
 	Register(db)
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS words (word VARCHAR(10))`)
+	err = db.Exec(`CREATE TABLE words (word VARCHAR(10))`)
 	if err != nil {
 		t.Fatal(err)
 	}

ext/zorder/zorder.go

@@ -0,0 +1,58 @@
+// Package zorder provides functions for z-order transformations.
+//
+// https://sqlite.org/src/doc/tip/ext/misc/zorder.c
+package zorder
+
+import (
+	"github.com/ncruces/go-sqlite3"
+	"github.com/ncruces/go-sqlite3/internal/util"
+)
+
+// Register registers the zorder and unzorder SQL functions.
+func Register(db *sqlite3.Conn) {
+	flags := sqlite3.DETERMINISTIC | sqlite3.INNOCUOUS
+	db.CreateFunction("zorder", -1, flags, zorder)
+	db.CreateFunction("unzorder", 3, flags, unzorder)
+}
+
+func zorder(ctx sqlite3.Context, arg ...sqlite3.Value) {
+	var x [63]int64
+	for i := range arg {
+		x[i] = arg[i].Int64()
+	}
+	if len(arg) > len(x) {
+		ctx.ResultError(util.ErrorString("zorder: too many parameters"))
+		return
+	}
+
+	var z int64
+	if len(arg) > 0 {
+		for i := 0; i < 63; i++ {
+			j := i % len(arg)
+			z |= (x[j] & 1) << i
+			x[j] >>= 1
+		}
+	}
+
+	for i := range arg {
+		if x[i] != 0 {
+			ctx.ResultError(util.ErrorString("zorder: parameter too large"))
+			return
+		}
+	}
+	ctx.ResultInt64(z)
+}
+
+func unzorder(ctx sqlite3.Context, arg ...sqlite3.Value) {
+	z := arg[0].Int64()
+	n := arg[1].Int64()
+	i := arg[2].Int64()
+
+	var k int
+	var x int64
+	for j := i; j < 63; j += n {
+		x |= ((z >> j) & 1) << k
+		k++
+	}
+	ctx.ResultInt64(x)
+}

ext/zorder/zorder_test.go

@@ -0,0 +1,106 @@
+package zorder_test
+
+import (
+	"testing"
+
+	"github.com/ncruces/go-sqlite3"
+	"github.com/ncruces/go-sqlite3/driver"
+	_ "github.com/ncruces/go-sqlite3/embed"
+	"github.com/ncruces/go-sqlite3/ext/zorder"
+)
+
+func TestRegister_zorder(t *testing.T) {
+	t.Parallel()
+
+	db, err := driver.Open(":memory:", func(c *sqlite3.Conn) error {
+		zorder.Register(c)
+		return nil
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+
+	var got int64
+	err = db.QueryRow(`SELECT zorder(2, 3)`).Scan(&got)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got != 14 {
+		t.Errorf("got %d, want 14", got)
+	}
+
+	err = db.QueryRow(`SELECT zorder(4, 5)`).Scan(&got)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got != 50 {
+		t.Errorf("got %d, want 14", got)
+	}
+
+	var check bool
+	err = db.QueryRow(`SELECT zorder(3, 4) BETWEEN zorder(2, 3) AND zorder(4, 5)`).Scan(&check)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !check {
+		t.Error("want true")
+	}
+
+	err = db.QueryRow(`SELECT zorder(2, 2) NOT BETWEEN zorder(2, 3) AND zorder(4, 5)`).Scan(&check)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !check {
+		t.Error("want true")
+	}
+}
+
+func TestRegister_unzorder(t *testing.T) {
+	t.Parallel()
+
+	db, err := driver.Open(":memory:", func(c *sqlite3.Conn) error {
+		zorder.Register(c)
+		return nil
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+
+	var got int64
+	err = db.QueryRow(`SELECT unzorder(zorder(3, 4), 2, 0)`).Scan(&got)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got != 3 {
+		t.Errorf("got %d, want 3", got)
+	}
+
+	err = db.QueryRow(`SELECT unzorder(zorder(3, 4), 2, 1)`).Scan(&got)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got != 4 {
+		t.Errorf("got %d, want 4", got)
+	}
+}
+
+func TestRegister_error(t *testing.T) {
+	t.Parallel()
+
+	db, err := driver.Open(":memory:", func(c *sqlite3.Conn) error {
+		zorder.Register(c)
+		return nil
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+
+	var got int64
+	err = db.QueryRow(`SELECT zorder(1, 2, 3, 100000)`).Scan(&got)
+	if err == nil {
+		t.Error("want error")
+	}
+}

func_test.go

@@ -18,7 +18,7 @@ func ExampleConn_CreateCollation() {
 	}
 	defer db.Close()
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS words (word VARCHAR(10))`)
+	err = db.Exec(`CREATE TABLE words (word VARCHAR(10))`)
 	if err != nil {
 		log.Fatal(err)
 	}
@@ -66,7 +66,7 @@ func ExampleConn_CreateFunction() {
 	}
 	defer db.Close()
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS words (word VARCHAR(10))`)
+	err = db.Exec(`CREATE TABLE words (word VARCHAR(10))`)
 	if err != nil {
 		log.Fatal(err)
 	}
@@ -111,7 +111,7 @@ func ExampleContext_SetAuxData() {
 	}
 	defer db.Close()
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS words (word VARCHAR(10))`)
+	err = db.Exec(`CREATE TABLE words (word VARCHAR(10))`)
 	if err != nil {
 		log.Fatal(err)
 	}

func_win_test.go

@@ -16,7 +16,7 @@ func ExampleConn_CreateWindowFunction() {
 	}
 	defer db.Close()
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS words (word VARCHAR(10))`)
+	err = db.Exec(`CREATE TABLE words (word VARCHAR(10))`)
 	if err != nil {
 		log.Fatal(err)
 	}

go.mod

@@ -5,10 +5,10 @@ go 1.21
 require (
 	github.com/ncruces/julianday v1.0.0
 	github.com/psanford/httpreadat v0.1.0
-	github.com/tetratelabs/wazero v1.6.0
-	golang.org/x/crypto v0.18.0
-	golang.org/x/sync v0.6.0
-	golang.org/x/sys v0.16.0
+	github.com/tetratelabs/wazero v1.7.1
+	golang.org/x/crypto v0.22.0
+	golang.org/x/sync v0.7.0
+	golang.org/x/sys v0.19.0
 	golang.org/x/text v0.14.0
 )
 

go.sum

@@ -2,13 +2,13 @@ github.com/ncruces/julianday v1.0.0 h1:fH0OKwa7NWvniGQtxdJRxAgkBMolni2BjDHaWTxqt
 github.com/ncruces/julianday v1.0.0/go.mod h1:Dusn2KvZrrovOMJuOt0TNXL6tB7U2E8kvza5fFc9G7g=
 github.com/psanford/httpreadat v0.1.0 h1:VleW1HS2zO7/4c7c7zNl33fO6oYACSagjJIyMIwZLUE=
 github.com/psanford/httpreadat v0.1.0/go.mod h1:Zg7P+TlBm3bYbyHTKv/EdtSJZn3qwbPwpfZ/I9GKCRE=
-github.com/tetratelabs/wazero v1.6.0 h1:z0H1iikCdP8t+q341xqepY4EWvHEw8Es7tlqiVzlP3g=
-github.com/tetratelabs/wazero v1.6.0/go.mod h1:0U0G41+ochRKoPKCJlh0jMg1CHkyfK8kDqiirMmKY8A=
-golang.org/x/crypto v0.18.0 h1:PGVlW0xEltQnzFZ55hkuX5+KLyrMYhHld1YHO4AKcdc=
-golang.org/x/crypto v0.18.0/go.mod h1:R0j02AL6hcrfOiy9T4ZYp/rcWeMxM3L6QYxlOuEG1mg=
-golang.org/x/sync v0.6.0 h1:5BMeUDZ7vkXGfEr1x9B4bRcTH4lpkTkpdh0T/J+qjbQ=
-golang.org/x/sync v0.6.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
-golang.org/x/sys v0.16.0 h1:xWw16ngr6ZMtmxDyKyIgsE93KNKz5HKmMa3b8ALHidU=
-golang.org/x/sys v0.16.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+github.com/tetratelabs/wazero v1.7.1 h1:QtSfd6KLc41DIMpDYlJdoMc6k7QTN246DM2+n2Y/Dx8=
+github.com/tetratelabs/wazero v1.7.1/go.mod h1:ytl6Zuh20R/eROuyDaGPkp82O9C/DJfXAwJfQ3X6/7Y=
+golang.org/x/crypto v0.22.0 h1:g1v0xeRhjcugydODzvb3mEM9SQ0HGp9s/nh3COQ/C30=
+golang.org/x/crypto v0.22.0/go.mod h1:vr6Su+7cTlO45qkww3VDJlzDn0ctJvRgYbC2NvXHt+M=
+golang.org/x/sync v0.7.0 h1:YsImfSBoP9QPYL0xyKJPq0gcaJdG3rInoqxTWbfQu9M=
+golang.org/x/sync v0.7.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
+golang.org/x/sys v0.19.0 h1:q5f1RH2jigJ1MoAWp2KTp3gm5zAGFUTarQZ5U386+4o=
+golang.org/x/sys v0.19.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/text v0.14.0 h1:ScX5w1eTa3QqT8oi6+ziP7dTV1S2+ALU0bI+0zXKWiQ=
 golang.org/x/text v0.14.0/go.mod h1:18ZOQIKpY8NJVqYksKHtTdi31H5itFRjB5/qKTNYzSU=

go.work.sum

@@ -1,3 +1,8 @@
+golang.org/x/mod v0.8.0 h1:LUYupSeNrTNCGzR/hVBk2NHZO4hXcVaW1k4Qx7rjPx8=
 golang.org/x/mod v0.8.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
-golang.org/x/net v0.10.0/go.mod h1:0qNGK6F8kojg2nk9dLZ2mShWaEBan6FAoqfSigmmuDg=
+golang.org/x/net v0.21.0 h1:AQyQV4dYCvJ7vGmJyKki9+PBdyvhkSd8EIx/qb0AYv4=
+golang.org/x/net v0.21.0/go.mod h1:bIjVDfnllIU7BJ2DNgfnXvpSvtn8VRwhlsaeUTyUS44=
+golang.org/x/term v0.19.0 h1:+ThwsDv+tYfnJFhF4L8jITxu1tdTWRTZpdsWgEgjL6Q=
+golang.org/x/term v0.19.0/go.mod h1:2CuTdWZ7KHSQwUzKva0cbMg6q2DMI3Mmxp+gKJbskEk=
+golang.org/x/tools v0.6.0 h1:BOw41kyTf3PuCW1pVQf8+Cyg8pMlkYB1oo9iJ6D/lKM=
 golang.org/x/tools v0.6.0/go.mod h1:Xwgl3UAJ/d3gWutnCtw505GrjyAbvKui8lOU390QaIU=

gormlite/ddlmod.go

@@ -13,6 +13,7 @@ import (
 
 var (
 	sqliteSeparator    = "`|\"|'|\t"
+	uniqueRegexp       = regexp.MustCompile(fmt.Sprintf(`^CONSTRAINT [%v]?[\w-]+[%v]? UNIQUE (.*)$`, sqliteSeparator, sqliteSeparator))
 	indexRegexp        = regexp.MustCompile(fmt.Sprintf(`(?is)CREATE(?: UNIQUE)? INDEX [%v]?[\w\d-]+[%v]?(?s:.*?)ON (.*)$`, sqliteSeparator, sqliteSeparator))
 	tableRegexp        = regexp.MustCompile(fmt.Sprintf(`(?is)(CREATE TABLE [%v]?[\w\d-]+[%v]?)(?:\s*\((.*)\))?`, sqliteSeparator, sqliteSeparator))
 	separatorRegexp    = regexp.MustCompile(fmt.Sprintf("[%v]", sqliteSeparator))
@@ -103,11 +104,24 @@ func parseDDL(strs ...string) (*ddl, error) {
 
 			for _, f := range result.fields {
 				fUpper := strings.ToUpper(f)
-				if strings.HasPrefix(fUpper, "CHECK") ||
-					strings.HasPrefix(fUpper, "CONSTRAINT") {
+				if strings.HasPrefix(fUpper, "CHECK") {
+					continue
+				}
+				if strings.HasPrefix(fUpper, "CONSTRAINT") {
+					matches := uniqueRegexp.FindStringSubmatch(f)
+					if len(matches) > 0 {
+						if columns := getAllColumns(matches[1]); len(columns) == 1 {
+							for idx, column := range result.columns {
+								if column.NameValue.String == columns[0] {
+									column.UniqueValue = sql.NullBool{Bool: true, Valid: true}
+									result.columns[idx] = column
+									break
+								}
+							}
+						}
+					}
 					continue
 				}
-
 				if strings.HasPrefix(fUpper, "PRIMARY KEY") {
 					for _, name := range getAllColumns(f) {
 						for idx, column := range result.columns {
@@ -159,14 +173,7 @@ func parseDDL(strs ...string) (*ddl, error) {
 				}
 			}
 		} else if matches := indexRegexp.FindStringSubmatch(str); len(matches) > 0 {
-			for _, column := range getAllColumns(matches[1]) {
-				for idx, c := range result.columns {
-					if c.NameValue.String == column {
-						c.UniqueValue = sql.NullBool{Bool: strings.ToUpper(strings.Fields(str)[1]) == "UNIQUE", Valid: true}
-						result.columns[idx] = c
-					}
-				}
-			}
+			// don't report Unique by UniqueIndex
 		} else {
 			return nil, errors.New("invalid DDL")
 		}
@@ -269,20 +276,6 @@ func (d *ddl) getColumns() []string {
 	return res
 }
 
-func (d *ddl) alterColumn(name, sql string) bool {
-	reg := regexp.MustCompile("^(`|'|\"| )" + regexp.QuoteMeta(name) + "(`|'|\"| ) .*?$")
-
-	for i := 0; i < len(d.fields); i++ {
-		if reg.MatchString(d.fields[i]) {
-			d.fields[i] = sql
-			return false
-		}
-	}
-
-	d.fields = append(d.fields, sql)
-	return true
-}
-
 func (d *ddl) removeColumn(name string) bool {
 	reg := regexp.MustCompile("^(`|'|\"| )" + regexp.QuoteMeta(name) + "(`|'|\"| ) .*?$")
 

gormlite/ddlmod_test.go

@@ -16,11 +16,12 @@ func TestParseDDL(t *testing.T) {
 		columns []migrator.ColumnType
 	}{
 		{"with_fk", []string{
-			"CREATE TABLE `notes` (`id` integer NOT NULL,`text` varchar(500) DEFAULT \"hello\",`age` integer DEFAULT 18,`user_id` integer,PRIMARY KEY (`id`),CONSTRAINT `fk_users_notes` FOREIGN KEY (`user_id`) REFERENCES `users`(`id`))",
+			"CREATE TABLE `notes` (" +
+				"`id` integer NOT NULL,`text` varchar(500) DEFAULT \"hello\",`age` integer DEFAULT 18,`user_id` integer,PRIMARY KEY (`id`),CONSTRAINT `fk_users_notes` FOREIGN KEY (`user_id`) REFERENCES `users`(`id`))",
 			"CREATE UNIQUE INDEX `idx_profiles_refer` ON `profiles`(`text`)",
 		}, 6, []migrator.ColumnType{
 			{NameValue: sql.NullString{String: "id", Valid: true}, DataTypeValue: sql.NullString{String: "integer", Valid: true}, ColumnTypeValue: sql.NullString{String: "integer", Valid: true}, PrimaryKeyValue: sql.NullBool{Bool: true, Valid: true}, NullableValue: sql.NullBool{Valid: true}, UniqueValue: sql.NullBool{Valid: true}, DefaultValueValue: sql.NullString{Valid: false}},
-			{NameValue: sql.NullString{String: "text", Valid: true}, DataTypeValue: sql.NullString{String: "varchar", Valid: true}, LengthValue: sql.NullInt64{Int64: 500, Valid: true}, ColumnTypeValue: sql.NullString{String: "varchar(500)", Valid: true}, DefaultValueValue: sql.NullString{String: "hello", Valid: true}, NullableValue: sql.NullBool{Bool: true, Valid: true}, UniqueValue: sql.NullBool{Bool: true, Valid: true}, PrimaryKeyValue: sql.NullBool{Valid: true}},
+			{NameValue: sql.NullString{String: "text", Valid: true}, DataTypeValue: sql.NullString{String: "varchar", Valid: true}, LengthValue: sql.NullInt64{Int64: 500, Valid: true}, ColumnTypeValue: sql.NullString{String: "varchar(500)", Valid: true}, DefaultValueValue: sql.NullString{String: "hello", Valid: true}, NullableValue: sql.NullBool{Bool: true, Valid: true}, UniqueValue: sql.NullBool{Bool: false, Valid: true}, PrimaryKeyValue: sql.NullBool{Valid: true}},
 			{NameValue: sql.NullString{String: "age", Valid: true}, DataTypeValue: sql.NullString{String: "integer", Valid: true}, ColumnTypeValue: sql.NullString{String: "integer", Valid: true}, DefaultValueValue: sql.NullString{String: "18", Valid: true}, NullableValue: sql.NullBool{Bool: true, Valid: true}, UniqueValue: sql.NullBool{Valid: true}, PrimaryKeyValue: sql.NullBool{Valid: true}},
 			{NameValue: sql.NullString{String: "user_id", Valid: true}, DataTypeValue: sql.NullString{String: "integer", Valid: true}, ColumnTypeValue: sql.NullString{String: "integer", Valid: true}, DefaultValueValue: sql.NullString{Valid: false}, NullableValue: sql.NullBool{Bool: true, Valid: true}, UniqueValue: sql.NullBool{Valid: true}, PrimaryKeyValue: sql.NullBool{Valid: true}},
 		},
@@ -56,28 +57,54 @@ func TestParseDDL(t *testing.T) {
 					ColumnTypeValue:   sql.NullString{String: "int", Valid: true},
 					NullableValue:     sql.NullBool{Bool: false, Valid: true},
 					DefaultValueValue: sql.NullString{Valid: false},
-					UniqueValue:       sql.NullBool{Bool: true, Valid: true},
+					UniqueValue:       sql.NullBool{Bool: false, Valid: true},
 					PrimaryKeyValue:   sql.NullBool{Valid: true},
 				},
 			},
-		},
-		{
+		}, {
 			"unique index",
 			[]string{
 				"CREATE TABLE `test-b` (`field` integer NOT NULL)",
 				"CREATE UNIQUE INDEX `idx_uq` ON `test-b`(`field`) WHERE field = 0",
 			},
 			1,
-			[]migrator.ColumnType{
-				{
-					NameValue:       sql.NullString{String: "field", Valid: true},
-					DataTypeValue:   sql.NullString{String: "integer", Valid: true},
-					ColumnTypeValue: sql.NullString{String: "integer", Valid: true},
-					PrimaryKeyValue: sql.NullBool{Bool: false, Valid: true},
-					UniqueValue:     sql.NullBool{Bool: true, Valid: true},
-					NullableValue:   sql.NullBool{Bool: false, Valid: true},
-				},
+			[]migrator.ColumnType{{
+				NameValue:       sql.NullString{String: "field", Valid: true},
+				DataTypeValue:   sql.NullString{String: "integer", Valid: true},
+				ColumnTypeValue: sql.NullString{String: "integer", Valid: true},
+				PrimaryKeyValue: sql.NullBool{Bool: false, Valid: true},
+				UniqueValue:     sql.NullBool{Bool: false, Valid: true},
+				NullableValue:   sql.NullBool{Bool: false, Valid: true},
+			}},
+		}, {
+			"normal index",
+			[]string{
+				"CREATE TABLE `test-c` (`field` integer NOT NULL)",
+				"CREATE INDEX `idx_uq` ON `test-c`(`field`)",
 			},
+			1,
+			[]migrator.ColumnType{{
+				NameValue:       sql.NullString{String: "field", Valid: true},
+				DataTypeValue:   sql.NullString{String: "integer", Valid: true},
+				ColumnTypeValue: sql.NullString{String: "integer", Valid: true},
+				PrimaryKeyValue: sql.NullBool{Bool: false, Valid: true},
+				UniqueValue:     sql.NullBool{Bool: false, Valid: true},
+				NullableValue:   sql.NullBool{Bool: false, Valid: true},
+			}},
+		}, {
+			"unique constraint",
+			[]string{
+				"CREATE TABLE `unique_struct` (`name` text,CONSTRAINT `uni_unique_struct_name` UNIQUE (`name`))",
+			},
+			2,
+			[]migrator.ColumnType{{
+				NameValue:       sql.NullString{String: "name", Valid: true},
+				DataTypeValue:   sql.NullString{String: "text", Valid: true},
+				ColumnTypeValue: sql.NullString{String: "text", Valid: true},
+				PrimaryKeyValue: sql.NullBool{Bool: false, Valid: true},
+				UniqueValue:     sql.NullBool{Bool: true, Valid: true},
+				NullableValue:   sql.NullBool{Bool: true, Valid: true},
+			}},
 		},
 		{
 			"non-unique index",

gormlite/download.sh

@@ -3,9 +3,9 @@ set -euo pipefail
 
 cd -P -- "$(dirname -- "$0")"
 
-curl -#OL "https://github.com/go-gorm/sqlite/raw/master/ddlmod.go"
-curl -#OL "https://github.com/go-gorm/sqlite/raw/master/ddlmod_test.go"
-curl -#OL "https://github.com/go-gorm/sqlite/raw/master/error_translator.go"
-curl -#OL "https://github.com/go-gorm/sqlite/raw/master/migrator.go"
-curl -#OL "https://github.com/go-gorm/sqlite/raw/master/sqlite.go"
-curl -#OL "https://github.com/go-gorm/sqlite/raw/master/sqlite_test.go"
+curl -#OL "https://github.com/go-gorm/sqlite/raw/v1.5.5/ddlmod.go"
+curl -#OL "https://github.com/go-gorm/sqlite/raw/v1.5.5/ddlmod_test.go"
+curl -#OL "https://github.com/go-gorm/sqlite/raw/v1.5.5/error_translator.go"
+curl -#OL "https://github.com/go-gorm/sqlite/raw/v1.5.5/migrator.go"
+curl -#OL "https://github.com/go-gorm/sqlite/raw/v1.5.5/sqlite.go"
+curl -#OL "https://github.com/go-gorm/sqlite/raw/v1.5.5/sqlite_test.go"

gormlite/go.mod

@@ -3,14 +3,14 @@ module github.com/ncruces/go-sqlite3/gormlite
 go 1.21
 
 require (
-	github.com/ncruces/go-sqlite3 v0.12.1
-	gorm.io/gorm v1.25.6
+	github.com/ncruces/go-sqlite3 v0.13.0
+	gorm.io/gorm v1.25.9
 )
 
 require (
 	github.com/jinzhu/inflection v1.0.0 // indirect
 	github.com/jinzhu/now v1.1.5 // indirect
 	github.com/ncruces/julianday v1.0.0 // indirect
-	github.com/tetratelabs/wazero v1.6.0 // indirect
-	golang.org/x/sys v0.16.0 // indirect
+	github.com/tetratelabs/wazero v1.7.0 // indirect
+	golang.org/x/sys v0.19.0 // indirect
 )

gormlite/go.sum

@@ -2,15 +2,15 @@ github.com/jinzhu/inflection v1.0.0 h1:K317FqzuhWc8YvSVlFMCCUb36O/S9MCKRDI7QkRKD
 github.com/jinzhu/inflection v1.0.0/go.mod h1:h+uFLlag+Qp1Va5pdKtLDYj+kHp5pxUVkryuEj+Srlc=
 github.com/jinzhu/now v1.1.5 h1:/o9tlHleP7gOFmsnYNz3RGnqzefHA47wQpKrrdTIwXQ=
 github.com/jinzhu/now v1.1.5/go.mod h1:d3SSVoowX0Lcu0IBviAWJpolVfI5UJVZZ7cO71lE/z8=
-github.com/ncruces/go-sqlite3 v0.12.1 h1:fxNoMQXIiMJ92B4umXyTYbNlk3xyQpZQ2S1Bojz8Z/Y=
-github.com/ncruces/go-sqlite3 v0.12.1/go.mod h1:+8dWcBxb2Yar4EcCwav1a21MpKZbztwOYBLSRYt9bMY=
+github.com/ncruces/go-sqlite3 v0.13.0 h1:+N1VHVLnrCJasyXdAKQL9MNTKC3wHZa8pLMUuP8wb3k=
+github.com/ncruces/go-sqlite3 v0.13.0/go.mod h1:y9zPUI+C42V9xuuJeN+tGhpOjr4gUHz2Pi2RLFVEdZg=
 github.com/ncruces/julianday v1.0.0 h1:fH0OKwa7NWvniGQtxdJRxAgkBMolni2BjDHaWTxqt7M=
 github.com/ncruces/julianday v1.0.0/go.mod h1:Dusn2KvZrrovOMJuOt0TNXL6tB7U2E8kvza5fFc9G7g=
-github.com/tetratelabs/wazero v1.6.0 h1:z0H1iikCdP8t+q341xqepY4EWvHEw8Es7tlqiVzlP3g=
-github.com/tetratelabs/wazero v1.6.0/go.mod h1:0U0G41+ochRKoPKCJlh0jMg1CHkyfK8kDqiirMmKY8A=
-golang.org/x/sys v0.16.0 h1:xWw16ngr6ZMtmxDyKyIgsE93KNKz5HKmMa3b8ALHidU=
-golang.org/x/sys v0.16.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+github.com/tetratelabs/wazero v1.7.0 h1:jg5qPydno59wqjpGrHph81lbtHzTrWzwwtD4cD88+hQ=
+github.com/tetratelabs/wazero v1.7.0/go.mod h1:ytl6Zuh20R/eROuyDaGPkp82O9C/DJfXAwJfQ3X6/7Y=
+golang.org/x/sys v0.19.0 h1:q5f1RH2jigJ1MoAWp2KTp3gm5zAGFUTarQZ5U386+4o=
+golang.org/x/sys v0.19.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/text v0.14.0 h1:ScX5w1eTa3QqT8oi6+ziP7dTV1S2+ALU0bI+0zXKWiQ=
 golang.org/x/text v0.14.0/go.mod h1:18ZOQIKpY8NJVqYksKHtTdi31H5itFRjB5/qKTNYzSU=
-gorm.io/gorm v1.25.6 h1:V92+vVda1wEISSOMtodHVRcUIOPYa2tgQtyF+DfFx+A=
-gorm.io/gorm v1.25.6/go.mod h1:hbnx/Oo0ChWMn1BIhpy1oYozzpM15i4YPuHDmfYtwg8=
+gorm.io/gorm v1.25.9 h1:wct0gxZIELDk8+ZqF/MVnHLkA1rvYlBWUMv2EdsK1g8=
+gorm.io/gorm v1.25.9/go.mod h1:hbnx/Oo0ChWMn1BIhpy1oYozzpM15i4YPuHDmfYtwg8=

gormlite/migrator.go

@@ -79,14 +79,28 @@ func (m _Migrator) AlterColumn(value interface{}, name string) error {
 	return m.RunWithoutForeignKey(func() error {
 		return m.recreateTable(value, nil, func(ddl *ddl, stmt *gorm.Statement) (*ddl, []interface{}, error) {
 			if field := stmt.Schema.LookUpField(name); field != nil {
-				if ddl.alterColumn(field.DBName, fmt.Sprintf("`%s` ?", field.DBName)) {
-					return nil, nil, fmt.Errorf("field `%s` not found in origin ddl, ddl= '%s'", name, ddl.compile())
+				var sqlArgs []interface{}
+				for i, f := range ddl.fields {
+					if matches := columnRegexp.FindStringSubmatch(f); len(matches) > 1 && matches[1] == field.DBName {
+						ddl.fields[i] = fmt.Sprintf("`%v` ?", field.DBName)
+						sqlArgs = []interface{}{m.FullDataTypeOf(field)}
+						// table created by old version might look like `CREATE TABLE ? (? varchar(10) UNIQUE)`.
+						// FullDataTypeOf doesn't contain UNIQUE, so we need to add unique constraint.
+						if strings.Contains(strings.ToUpper(matches[3]), " UNIQUE") {
+							uniName := m.DB.NamingStrategy.UniqueName(stmt.Table, field.DBName)
+							uni, _ := m.GuessConstraintInterfaceAndTable(stmt, uniName)
+							if uni != nil {
+								uniSQL, uniArgs := uni.Build()
+								ddl.addConstraint(uniName, uniSQL)
+								sqlArgs = append(sqlArgs, uniArgs...)
+							}
+						}
+						break
+					}
 				}
-
-				return ddl, []interface{}{m.FullDataTypeOf(field)}, nil
+				return ddl, sqlArgs, nil
 			}
-
-			return nil, nil, fmt.Errorf("failed to alter field with name `%s`", name)
+			return nil, nil, fmt.Errorf("failed to alter field with name %v", name)
 		})
 	})
 }
@@ -153,7 +167,7 @@ func (m _Migrator) DropColumn(value interface{}, name string) error {
 
 func (m _Migrator) CreateConstraint(value interface{}, name string) error {
 	return m.RunWithValue(value, func(stmt *gorm.Statement) error {
-		constraint, chk, table := m.GuessConstraintAndTable(stmt, name)
+		constraint, table := m.GuessConstraintInterfaceAndTable(stmt, name)
 
 		return m.recreateTable(value, &table,
 			func(ddl *ddl, stmt *gorm.Statement) (*ddl, []interface{}, error) {
@@ -164,12 +178,8 @@ func (m _Migrator) CreateConstraint(value interface{}, name string) error {
 				)
 
 				if constraint != nil {
-					constraintName = constraint.Name
-					constraintSql, constraintValues = buildConstraint(constraint)
-				} else if chk != nil {
-					constraintName = chk.Name
-					constraintSql = "CONSTRAINT ? CHECK (?)"
-					constraintValues = []interface{}{clause.Column{Name: chk.Name}, clause.Expr{SQL: chk.Constraint}}
+					constraintName = constraint.GetName()
+					constraintSql, constraintValues = constraint.Build()
 				} else {
 					return nil, nil, nil
 				}
@@ -182,11 +192,9 @@ func (m _Migrator) CreateConstraint(value interface{}, name string) error {
 
 func (m _Migrator) DropConstraint(value interface{}, name string) error {
 	return m.RunWithValue(value, func(stmt *gorm.Statement) error {
-		constraint, chk, table := m.GuessConstraintAndTable(stmt, name)
+		constraint, table := m.GuessConstraintInterfaceAndTable(stmt, name)
 		if constraint != nil {
-			name = constraint.Name
-		} else if chk != nil {
-			name = chk.Name
+			name = constraint.GetName()
 		}
 
 		return m.recreateTable(value, &table,
@@ -200,11 +208,9 @@ func (m _Migrator) DropConstraint(value interface{}, name string) error {
 func (m _Migrator) HasConstraint(value interface{}, name string) bool {
 	var count int64
 	m.RunWithValue(value, func(stmt *gorm.Statement) error {
-		constraint, chk, table := m.GuessConstraintAndTable(stmt, name)
+		constraint, table := m.GuessConstraintInterfaceAndTable(stmt, name)
 		if constraint != nil {
-			name = constraint.Name
-		} else if chk != nil {
-			name = chk.Name
+			name = constraint.GetName()
 		}
 
 		m.DB.Raw(
@@ -317,26 +323,44 @@ func (m _Migrator) DropIndex(value interface{}, name string) error {
 	})
 }
 
-func buildConstraint(constraint *schema.Constraint) (sql string, results []interface{}) {
-	sql = "CONSTRAINT ? FOREIGN KEY ? REFERENCES ??"
-	if constraint.OnDelete != "" {
-		sql += " ON DELETE " + constraint.OnDelete
-	}
+type _Index struct {
+	Seq     int
+	Name    string
+	Unique  bool
+	Origin  string
+	Partial bool
+}
 
-	if constraint.OnUpdate != "" {
-		sql += " ON UPDATE " + constraint.OnUpdate
-	}
-
-	var foreignKeys, references []interface{}
-	for _, field := range constraint.ForeignKeys {
-		foreignKeys = append(foreignKeys, clause.Column{Name: field.DBName})
-	}
-
-	for _, field := range constraint.References {
-		references = append(references, clause.Column{Name: field.DBName})
-	}
-	results = append(results, clause.Table{Name: constraint.Name}, foreignKeys, clause.Table{Name: constraint.ReferenceSchema.Table}, references)
-	return
+// GetIndexes return Indexes []gorm.Index and execErr error,
+// See the [doc]
+//
+// [doc]: https://sqlite.org/pragma.html#pragma_index_list
+func (m _Migrator) GetIndexes(value interface{}) ([]gorm.Index, error) {
+	indexes := make([]gorm.Index, 0)
+	err := m.RunWithValue(value, func(stmt *gorm.Statement) error {
+		rst := make([]*_Index, 0)
+		if err := m.DB.Debug().Raw("SELECT * FROM PRAGMA_index_list(?)", stmt.Table).Scan(&rst).Error; err != nil { // alias `PRAGMA index_list(?)`
+			return err
+		}
+		for _, index := range rst {
+			if index.Origin == "u" { // skip the index was created by a UNIQUE constraint
+				continue
+			}
+			var columns []string
+			if err := m.DB.Raw("SELECT name FROM PRAGMA_index_info(?)", index.Name).Scan(&columns).Error; err != nil { // alias `PRAGMA index_info(?)`
+				return err
+			}
+			indexes = append(indexes, &migrator.Index{
+				TableName:       stmt.Table,
+				NameValue:       index.Name,
+				ColumnList:      columns,
+				PrimaryKeyValue: sql.NullBool{Bool: index.Origin == "pk", Valid: true}, // The exceptions are INTEGER PRIMARY KEY
+				UniqueValue:     sql.NullBool{Bool: index.Unique, Valid: true},
+			})
+		}
+		return nil
+	})
+	return indexes, err
 }
 
 func (m _Migrator) getRawDDL(table string) (string, error) {

gormlite/test.sh

@@ -3,10 +3,11 @@ set -euo pipefail
 
 cd -P -- "$(dirname -- "$0")"
 
+rm -rf gorm/ tests/
+go work use -r .
 go test
 
-rm -rf gorm/ tests/
-git clone --branch v1.25.6 --filter=blob:none https://github.com/go-gorm/gorm.git
+git clone --branch v1.25.9 --filter=blob:none https://github.com/go-gorm/gorm.git
 mv gorm/tests tests
 rm -rf gorm/
 

internal/util/alloc.go

@@ -0,0 +1,71 @@
+//go:build unix
+
+package util
+
+import (
+	"math"
+
+	"github.com/tetratelabs/wazero/experimental"
+	"golang.org/x/sys/unix"
+)
+
+func mmappedAllocator(cap, max uint64) experimental.LinearMemory {
+	// Round up to the page size.
+	rnd := uint64(unix.Getpagesize() - 1)
+	max = (max + rnd) &^ rnd
+	cap = (cap + rnd) &^ rnd
+
+	if max > math.MaxInt {
+		// This ensures int(max) overflows to a negative value,
+		// and unix.Mmap returns EINVAL.
+		max = math.MaxUint64
+	}
+	// Reserve max bytes of address space, to ensure we won't need to move it.
+	// A protected, private, anonymous mapping should not commit memory.
+	b, err := unix.Mmap(-1, 0, int(max), unix.PROT_NONE, unix.MAP_PRIVATE|unix.MAP_ANON)
+	if err != nil {
+		panic(err)
+	}
+	// Commit the initial cap bytes of memory.
+	err = unix.Mprotect(b[:cap], unix.PROT_READ|unix.PROT_WRITE)
+	if err != nil {
+		unix.Munmap(b)
+		panic(err)
+	}
+	return &mmappedMemory{buf: b[:cap]}
+}
+
+// The slice covers the entire mmapped memory:
+//   - len(buf) is the already committed memory,
+//   - cap(buf) is the reserved address space.
+type mmappedMemory struct {
+	buf []byte
+}
+
+func (m *mmappedMemory) Reallocate(size uint64) []byte {
+	if com := uint64(len(m.buf)); com < size {
+		// Round up to the page size.
+		rnd := uint64(unix.Getpagesize() - 1)
+		new := (size + rnd) &^ rnd
+
+		// Commit additional memory up to new bytes.
+		err := unix.Mprotect(m.buf[com:new], unix.PROT_READ|unix.PROT_WRITE)
+		if err != nil {
+			panic(err)
+		}
+
+		// Update committed memory.
+		m.buf = m.buf[:new]
+	}
+	// Limit returned capacity because bytes beyond
+	// len(m.buf) have not yet been committed.
+	return m.buf[:size:len(m.buf)]
+}
+
+func (m *mmappedMemory) Free() {
+	err := unix.Munmap(m.buf[:cap(m.buf)])
+	if err != nil {
+		panic(err)
+	}
+	m.buf = nil
+}

internal/util/handle.go

@@ -3,21 +3,11 @@ package util
 import (
 	"context"
 	"io"
-
-	"github.com/tetratelabs/wazero/experimental"
 )
 
-type handleKey struct{}
 type handleState struct {
 	handles []any
-	empty   int
-}
-
-func NewContext(ctx context.Context) context.Context {
-	state := new(handleState)
-	ctx = experimental.WithCloseNotifier(ctx, state)
-	ctx = context.WithValue(ctx, handleKey{}, state)
-	return ctx
+	holes   int
 }
 
 func (s *handleState) CloseNotify(ctx context.Context, exitCode uint32) {
@@ -27,14 +17,14 @@ func (s *handleState) CloseNotify(ctx context.Context, exitCode uint32) {
 		}
 	}
 	s.handles = nil
-	s.empty = 0
+	s.holes = 0
 }
 
 func GetHandle(ctx context.Context, id uint32) any {
 	if id == 0 {
 		return nil
 	}
-	s := ctx.Value(handleKey{}).(*handleState)
+	s := ctx.Value(moduleKey{}).(*moduleState)
 	return s.handles[^id]
 }
 
@@ -42,10 +32,10 @@ func DelHandle(ctx context.Context, id uint32) error {
 	if id == 0 {
 		return nil
 	}
-	s := ctx.Value(handleKey{}).(*handleState)
+	s := ctx.Value(moduleKey{}).(*moduleState)
 	a := s.handles[^id]
 	s.handles[^id] = nil
-	s.empty++
+	s.holes++
 	if c, ok := a.(io.Closer); ok {
 		return c.Close()
 	}
@@ -56,13 +46,13 @@ func AddHandle(ctx context.Context, a any) (id uint32) {
 	if a == nil {
 		panic(NilErr)
 	}
-	s := ctx.Value(handleKey{}).(*handleState)
+	s := ctx.Value(moduleKey{}).(*moduleState)
 
 	// Find an empty slot.
-	if s.empty > cap(s.handles)-len(s.handles) {
+	if s.holes > cap(s.handles)-len(s.handles) {
 		for id, h := range s.handles {
 			if h == nil {
-				s.empty--
+				s.holes--
 				s.handles[id] = a
 				return ^uint32(id)
 			}

internal/util/mmap.go

@@ -0,0 +1,106 @@
+//go:build (darwin || linux || illumos) && (amd64 || arm64 || riscv64) && !sqlite3_flock && !sqlite3_noshm && !sqlite3_nosys
+
+package util
+
+import (
+	"context"
+	"os"
+	"unsafe"
+
+	"github.com/tetratelabs/wazero/api"
+	"github.com/tetratelabs/wazero/experimental"
+	"golang.org/x/sys/unix"
+)
+
+type mmapState struct {
+	regions []*MappedRegion
+	enabled bool
+}
+
+func (s *mmapState) init(ctx context.Context, enabled bool) context.Context {
+	if s.enabled = enabled; enabled {
+		return experimental.WithMemoryAllocator(ctx,
+			experimental.MemoryAllocatorFunc(mmappedAllocator))
+	}
+	return ctx
+}
+
+func CanMap(ctx context.Context) bool {
+	s := ctx.Value(moduleKey{}).(*moduleState)
+	return s.mmapState.enabled
+}
+
+func (s *mmapState) new(ctx context.Context, mod api.Module, size int32) *MappedRegion {
+	// Find unused region.
+	for _, r := range s.regions {
+		if !r.used && r.size == size {
+			return r
+		}
+	}
+
+	// Allocate page aligned memmory.
+	alloc := mod.ExportedFunction("aligned_alloc")
+	stack := [2]uint64{
+		uint64(unix.Getpagesize()),
+		uint64(size),
+	}
+	if err := alloc.CallWithStack(ctx, stack[:]); err != nil {
+		panic(err)
+	}
+	if stack[0] == 0 {
+		panic(OOMErr)
+	}
+
+	// Save the newly allocated region.
+	ptr := uint32(stack[0])
+	buf := View(mod, ptr, uint64(size))
+	addr := uintptr(unsafe.Pointer(&buf[0]))
+	s.regions = append(s.regions, &MappedRegion{
+		Ptr:  ptr,
+		addr: addr,
+		size: size,
+	})
+	return s.regions[len(s.regions)-1]
+}
+
+type MappedRegion struct {
+	addr uintptr
+	Ptr  uint32
+	size int32
+	used bool
+}
+
+func MapRegion(ctx context.Context, mod api.Module, f *os.File, offset int64, size int32, prot int) (*MappedRegion, error) {
+	s := ctx.Value(moduleKey{}).(*moduleState)
+	r := s.new(ctx, mod, size)
+	err := r.mmap(f, offset, prot)
+	if err != nil {
+		return nil, err
+	}
+	return r, nil
+}
+
+func (r *MappedRegion) Unmap() error {
+	// We can't munmap the region, otherwise it could be remaped.
+	// Instead, convert it to a protected, private, anonymous mapping.
+	// If successful, it can be reused for a subsequent mmap.
+	_, err := mmap(r.addr, uintptr(r.size),
+		unix.PROT_NONE, unix.MAP_PRIVATE|unix.MAP_ANON|unix.MAP_FIXED,
+		-1, 0)
+	r.used = err != nil
+	return err
+}
+
+func (r *MappedRegion) mmap(f *os.File, offset int64, prot int) error {
+	_, err := mmap(r.addr, uintptr(r.size),
+		prot, unix.MAP_SHARED|unix.MAP_FIXED,
+		int(f.Fd()), offset)
+	r.used = err == nil
+	return err
+}
+
+// We need the low level mmap for MAP_FIXED to work.
+// Bind the syscall version hoping that it is more stable.
+
+//go:linkname mmap syscall.mmap
+func mmap(addr, length uintptr, prot, flag, fd int, pos int64) (*byte, error)

internal/util/mmap_other.go

@@ -0,0 +1,15 @@
+//go:build !(darwin || linux || illumos) || !(amd64 || arm64 || riscv64) || sqlite3_flock || sqlite3_noshm || sqlite3_nosys
+
+package util
+
+import "context"
+
+type mmapState struct{}
+
+func (s *mmapState) init(ctx context.Context, _ bool) context.Context {
+	return ctx
+}
+
+func CanMap(ctx context.Context) bool {
+	return false
+}

internal/util/module.go

@@ -0,0 +1,21 @@
+package util
+
+import (
+	"context"
+
+	"github.com/tetratelabs/wazero/experimental"
+)
+
+type moduleKey struct{}
+type moduleState struct {
+	handleState
+	mmapState
+}
+
+func NewContext(ctx context.Context, mappableMemory bool) context.Context {
+	state := new(moduleState)
+	ctx = context.WithValue(ctx, moduleKey{}, state)
+	ctx = experimental.WithCloseNotifier(ctx, state)
+	ctx = state.mmapState.init(ctx, mappableMemory)
+	return ctx
+}

sqlite.go

@@ -15,14 +15,14 @@ import (
 	"github.com/tetratelabs/wazero/api"
 )
 
-// Configure SQLite WASM.
+// Configure SQLite Wasm.
 //
-// Importing package embed initializes these
+// Importing package embed initializes [Binary]
 // with an appropriate build of SQLite:
 //
 //	import _ "github.com/ncruces/go-sqlite3/embed"
 var (
-	Binary []byte // WASM binary to load.
+	Binary []byte // Wasm binary to load.
 	Path   string // Path to load the binary from.
 
 	RuntimeConfig wazero.RuntimeConfig
@@ -85,10 +85,10 @@ func instantiateSQLite() (sqlt *sqlite, err error) {
 	}
 
 	sqlt = new(sqlite)
-	sqlt.ctx = util.NewContext(context.Background())
+	sqlt.ctx = util.NewContext(context.Background(), vfs.SupportsSharedMemory)
 
 	sqlt.mod, err = instance.runtime.InstantiateModule(sqlt.ctx,
-		instance.compiled, wazero.NewModuleConfig())
+		instance.compiled, wazero.NewModuleConfig().WithName(""))
 	if err != nil {
 		return nil, err
 	}
@@ -99,8 +99,8 @@ func instantiateSQLite() (sqlt *sqlite, err error) {
 	}
 
 	sqlt.freer = util.ReadUint32(sqlt.mod, uint32(global.Get()))
-	if err != nil {
-		return nil, err
+	if sqlt.freer == 0 {
+		return nil, util.BadBinaryErr
 	}
 	return sqlt, nil
 }
@@ -274,7 +274,7 @@ func (a *arena) new(size uint64) uint32 {
 }
 
 func (a *arena) bytes(b []byte) uint32 {
-	if b == nil {
+	if (*[0]byte)(b) == nil {
 		return 0
 	}
 	ptr := a.new(uint64(len(b)))
@@ -294,6 +294,8 @@ func exportCallbacks(env wazero.HostModuleBuilder) wazero.HostModuleBuilder {
 	util.ExportFuncII(env, "go_commit_hook", commitCallback)
 	util.ExportFuncVI(env, "go_rollback_hook", rollbackCallback)
 	util.ExportFuncVIIIIJ(env, "go_update_hook", updateCallback)
+	util.ExportFuncIIIII(env, "go_wal_hook", walCallback)
+	util.ExportFuncIIIIII(env, "go_autovacuum_pages", autoVacuumCallback)
 	util.ExportFuncIIIIIII(env, "go_authorizer", authorizerCallback)
 	util.ExportFuncVIII(env, "go_log", logCallback)
 	util.ExportFuncVI(env, "go_destroy", destroyCallback)

sqlite3/date.patch

@@ -0,0 +1,556 @@
+# Backport from 3.46.
+# https://sqlite.org/draft/releaselog/current.html
+--- sqlite3.c.orig
++++ sqlite3.c
+@@ -71,13 +71,14 @@ struct DateTime {
+   int tz;             /* Timezone offset in minutes */
+   double s;           /* Seconds */
+   char validJD;       /* True (1) if iJD is valid */
+-  char rawS;          /* Raw numeric value stored in s */
+   char validYMD;      /* True (1) if Y,M,D are valid */
+   char validHMS;      /* True (1) if h,m,s are valid */
+-  char validTZ;       /* True (1) if tz is valid */
+-  char tzSet;         /* Timezone was set explicitly */
+-  char isError;       /* An overflow has occurred */
+-  char useSubsec;     /* Display subsecond precision */
++  char nFloor;            /* Days to implement "floor" */
++  unsigned rawS      : 1; /* Raw numeric value stored in s */
++  unsigned isError   : 1; /* An overflow has occurred */
++  unsigned useSubsec : 1; /* Display subsecond precision */
++  unsigned isUtc     : 1; /* Time is known to be UTC */
++  unsigned isLocal   : 1; /* Time is known to be localtime */
+ };
+ 
+ 
+@@ -175,6 +176,8 @@ static int parseTimezone(const char *zDate, DateTime *p){
+     sgn = +1;
+   }else if( c=='Z' || c=='z' ){
+     zDate++;
++    p->isLocal = 0;
++    p->isUtc = 1;
+     goto zulu_time;
+   }else{
+     return c!=0;
+@@ -187,7 +190,6 @@ static int parseTimezone(const char *zDate, DateTime *p){
+   p->tz = sgn*(nMn + nHr*60);
+ zulu_time:
+   while( sqlite3Isspace(*zDate) ){ zDate++; }
+-  p->tzSet = 1;
+   return *zDate!=0;
+ }
+ 
+@@ -231,7 +233,6 @@ static int parseHhMmSs(const char *zDate, DateTime *p){
+   p->m = m;
+   p->s = s + ms;
+   if( parseTimezone(zDate, p) ) return 1;
+-  p->validTZ = (p->tz!=0)?1:0;
+   return 0;
+ }
+ 
+@@ -278,15 +279,40 @@ static void computeJD(DateTime *p){
+   p->validJD = 1;
+   if( p->validHMS ){
+     p->iJD += p->h*3600000 + p->m*60000 + (sqlite3_int64)(p->s*1000 + 0.5);
+-    if( p->validTZ ){
++    if( p->tz ){
+       p->iJD -= p->tz*60000;
+       p->validYMD = 0;
+       p->validHMS = 0;
+-      p->validTZ = 0;
++      p->tz = 0;
++      p->isUtc = 1;
++      p->isLocal = 0;
+     }
+   }
+ }
+ 
++/*
++** Given the YYYY-MM-DD information current in p, determine if there
++** is day-of-month overflow and set nFloor to the number of days that
++** would need to be subtracted from the date in order to bring the
++** date back to the end of the month.
++*/
++static void computeFloor(DateTime *p){
++  assert( p->validYMD || p->isError );
++  assert( p->D>=0 && p->D<=31 );
++  assert( p->M>=0 && p->M<=12 );
++  if( p->D<=28 ){
++    p->nFloor = 0;
++  }else if( (1<<p->M) & 0x15aa ){
++    p->nFloor = 0;
++  }else if( p->M!=2 ){
++    p->nFloor = (p->D==31);
++  }else if( p->Y%4!=0 || (p->Y%100==0 && p->Y%400!=0) ){
++    p->nFloor = p->D - 28;
++  }else{
++    p->nFloor = p->D - 29;
++  }
++}
++
+ /*
+ ** Parse dates of the form
+ **
+@@ -325,12 +351,16 @@ static int parseYyyyMmDd(const char *zDate, DateTime *p){
+   p->Y = neg ? -Y : Y;
+   p->M = M;
+   p->D = D;
+-  if( p->validTZ ){
++  computeFloor(p);
++  if( p->tz ){
+     computeJD(p);
+   }
+   return 0;
+ }
+ 
++
++static void clearYMD_HMS_TZ(DateTime *p);  /* Forward declaration */
++
+ /*
+ ** Set the time to the current time reported by the VFS.
+ **
+@@ -340,6 +370,9 @@ static int setDateTimeToCurrent(sqlite3_context *context, DateTime *p){
+   p->iJD = sqlite3StmtCurrentTime(context);
+   if( p->iJD>0 ){
+     p->validJD = 1;
++    p->isUtc = 1;
++    p->isLocal = 0;
++    clearYMD_HMS_TZ(p);
+     return 0;
+   }else{
+     return 1;
+@@ -478,7 +511,7 @@ static void computeYMD_HMS(DateTime *p){
+ static void clearYMD_HMS_TZ(DateTime *p){
+   p->validYMD = 0;
+   p->validHMS = 0;
+-  p->validTZ = 0;
++  p->tz = 0;
+ }
+ 
+ #ifndef SQLITE_OMIT_LOCALTIME
+@@ -610,7 +643,7 @@ static int toLocaltime(
+   p->validHMS = 1;
+   p->validJD = 0;
+   p->rawS = 0;
+-  p->validTZ = 0;
++  p->tz = 0;
+   p->isError = 0;
+   return SQLITE_OK;
+ }
+@@ -630,12 +663,12 @@ static const struct {
+   float rLimit;       /* Maximum NNN value for this transform */
+   float rXform;       /* Constant used for this transform */
+ } aXformType[] = {
+-  { 6, "second", 4.6427e+14,       1.0  },
+-  { 6, "minute", 7.7379e+12,      60.0  },
+-  { 4, "hour",   1.2897e+11,    3600.0  },
+-  { 3, "day",    5373485.0,    86400.0  },
+-  { 5, "month",  176546.0,   2592000.0  },
+-  { 4, "year",   14713.0,   31536000.0  },
++  /* 0 */ { 6, "second",   4.6427e+14,         1.0  },
++  /* 1 */ { 6, "minute",   7.7379e+12,        60.0  },
++  /* 2 */ { 4, "hour",     1.2897e+11,      3600.0  },
++  /* 3 */ { 3, "day",      5373485.0,      86400.0  },
++  /* 4 */ { 5, "month",    176546.0,  30.0*86400.0  },
++  /* 5 */ { 4, "year",     14713.0,  365.0*86400.0  },
+ };
+ 
+ /*
+@@ -667,14 +700,20 @@ static void autoAdjustDate(DateTime *p){
+ **     NNN.NNNN seconds
+ **     NNN months
+ **     NNN years
++**     +/-YYYY-MM-DD HH:MM:SS.SSS
++**     ceiling
++**     floor
+ **     start of month
+ **     start of year
+ **     start of week
+ **     start of day
+ **     weekday N
+ **     unixepoch
++**     auto
+ **     localtime
+ **     utc
++**     subsec
++**     subsecond
+ **
+ ** Return 0 on success and 1 if there is any kind of error. If the error
+ ** is in a system call (i.e. localtime()), then an error message is written
+@@ -705,6 +744,37 @@ static int parseModifier(
+       }
+       break;
+     }
++    case 'c': {
++      /*
++      **    ceiling
++      **
++      ** Resolve day-of-month overflow by rolling forward into the next
++      ** month.  As this is the default action, this modifier is really
++      ** a no-op that is only included for symmetry.  See "floor".
++      */
++      if( sqlite3_stricmp(z, "ceiling")==0 ){
++        computeJD(p);
++        clearYMD_HMS_TZ(p);
++        rc = 0;
++        p->nFloor = 0;
++      }
++      break;
++    }
++    case 'f': {
++      /*
++      **    floor
++      **
++      ** Resolve day-of-month overflow by rolling back to the end of the
++      ** previous month.
++      */
++      if( sqlite3_stricmp(z, "floor")==0 ){
++        computeJD(p);
++        p->iJD -= p->nFloor*86400000;
++        clearYMD_HMS_TZ(p);
++        rc = 0;
++      }
++      break;
++    }
+     case 'j': {
+       /*
+       **    julianday
+@@ -731,7 +801,9 @@ static int parseModifier(
+       ** show local time.
+       */
+       if( sqlite3_stricmp(z, "localtime")==0 && sqlite3NotPureFunc(pCtx) ){
+-        rc = toLocaltime(p, pCtx);
++        rc = p->isLocal ? SQLITE_OK : toLocaltime(p, pCtx);
++        p->isUtc = 0;
++        p->isLocal = 1;
+       }
+       break;
+     }
+@@ -756,7 +828,7 @@ static int parseModifier(
+       }
+ #ifndef SQLITE_OMIT_LOCALTIME
+       else if( sqlite3_stricmp(z, "utc")==0 && sqlite3NotPureFunc(pCtx) ){
+-        if( p->tzSet==0 ){
++        if( p->isUtc==0 ){
+           i64 iOrigJD;              /* Original localtime */
+           i64 iGuess;               /* Guess at the corresponding utc time */
+           int cnt = 0;              /* Safety to prevent infinite loop */
+@@ -779,7 +851,8 @@ static int parseModifier(
+           memset(p, 0, sizeof(*p));
+           p->iJD = iGuess;
+           p->validJD = 1;
+-          p->tzSet = 1;
++          p->isUtc = 1;
++          p->isLocal = 0;
+         }
+         rc = SQLITE_OK;
+       }
+@@ -799,7 +872,7 @@ static int parseModifier(
+                && r>=0.0 && r<7.0 && (n=(int)r)==r ){
+         sqlite3_int64 Z;
+         computeYMD_HMS(p);
+-        p->validTZ = 0;
++        p->tz = 0;
+         p->validJD = 0;
+         computeJD(p);
+         Z = ((p->iJD + 129600000)/86400000) % 7;
+@@ -839,7 +912,7 @@ static int parseModifier(
+       p->h = p->m = 0;
+       p->s = 0.0;
+       p->rawS = 0;
+-      p->validTZ = 0;
++      p->tz = 0;
+       p->validJD = 0;
+       if( sqlite3_stricmp(z,"month")==0 ){
+         p->D = 1;
+@@ -910,6 +983,7 @@ static int parseModifier(
+         x = p->M>0 ? (p->M-1)/12 : (p->M-12)/12;
+         p->Y += x;
+         p->M -= x*12;
++        computeFloor(p);
+         computeJD(p);
+         p->validHMS = 0;
+         p->validYMD = 0;
+@@ -956,11 +1030,12 @@ static int parseModifier(
+       z += n;
+       while( sqlite3Isspace(*z) ) z++;
+       n = sqlite3Strlen30(z);
+-      if( n>10 || n<3 ) break;
++      if( n<3 || n>10 ) break;
+       if( sqlite3UpperToLower[(u8)z[n-1]]=='s' ) n--;
+       computeJD(p);
+       assert( rc==1 );
+       rRounder = r<0 ? -0.5 : +0.5;
++      p->nFloor = 0;
+       for(i=0; i<ArraySize(aXformType); i++){
+         if( aXformType[i].nName==n
+          && sqlite3_strnicmp(aXformType[i].zName, z, n)==0
+@@ -968,21 +1043,24 @@ static int parseModifier(
+         ){
+           switch( i ){
+             case 4: { /* Special processing to add months */
+-              assert( strcmp(aXformType[i].zName,"month")==0 );
++              assert( strcmp(aXformType[4].zName,"month")==0 );
+               computeYMD_HMS(p);
+               p->M += (int)r;
+               x = p->M>0 ? (p->M-1)/12 : (p->M-12)/12;
+               p->Y += x;
+               p->M -= x*12;
++              computeFloor(p);
+               p->validJD = 0;
+               r -= (int)r;
+               break;
+             }
+             case 5: { /* Special processing to add years */
+               int y = (int)r;
+-              assert( strcmp(aXformType[i].zName,"year")==0 );
++              assert( strcmp(aXformType[5].zName,"year")==0 );
+               computeYMD_HMS(p);
++              assert( p->M>=0 && p->M<=12 );
+               p->Y += y;
++              computeFloor(p);
+               p->validJD = 0;
+               r -= (int)r;
+               break;
+@@ -1236,22 +1314,83 @@ static void dateFunc(
+   }
+ }
+ 
++/*
++** Compute the number of days after the most recent January 1.
++**
++** In other words, compute the zero-based day number for the
++** current year:
++**
++**   Jan01 = 0,  Jan02 = 1, ..., Jan31 = 30, Feb01 = 31, ...
++**   Dec31 = 364 or 365.
++*/
++static int daysAfterJan01(DateTime *pDate){
++  DateTime jan01 = *pDate;
++  assert( jan01.validYMD );
++  assert( jan01.validHMS );
++  assert( pDate->validJD );
++  jan01.validJD = 0;
++  jan01.M = 1;
++  jan01.D = 1;
++  computeJD(&jan01);
++  return (int)((pDate->iJD-jan01.iJD+43200000)/86400000);
++}
++
++/*
++** Return the number of days after the most recent Monday.
++**
++** In other words, return the day of the week according
++** to this code:
++**
++**   0=Monday, 1=Tuesday, 2=Wednesday, ..., 6=Sunday.
++*/
++static int daysAfterMonday(DateTime *pDate){
++  assert( pDate->validJD );
++  return (int)((pDate->iJD+43200000)/86400000) % 7;
++}
++
++/*
++** Return the number of days after the most recent Sunday.
++**
++** In other words, return the day of the week according
++** to this code:
++**
++**   0=Sunday, 1=Monday, 2=Tues, ..., 6=Saturday
++*/
++static int daysAfterSunday(DateTime *pDate){
++  assert( pDate->validJD );
++  return (int)((pDate->iJD+129600000)/86400000) % 7;
++}
++
+ /*
+ **    strftime( FORMAT, TIMESTRING, MOD, MOD, ...)
+ **
+ ** Return a string described by FORMAT.  Conversions as follows:
+ **
+-**   %d  day of month
++**   %d  day of month  01-31
++**   %e  day of month  1-31
+ **   %f  ** fractional seconds  SS.SSS
++**   %F  ISO date.  YYYY-MM-DD
++**   %G  ISO year corresponding to %V 0000-9999.
++**   %g  2-digit ISO year corresponding to %V 00-99
+ **   %H  hour 00-24
+-**   %j  day of year 000-366
++**   %k  hour  0-24  (leading zero converted to space)
++**   %I  hour 01-12
++**   %j  day of year 001-366
+ **   %J  ** julian day number
++**   %l  hour  1-12  (leading zero converted to space)
+ **   %m  month 01-12
+ **   %M  minute 00-59
++**   %p  "am" or "pm"
++**   %P  "AM" or "PM"
++**   %R  time as HH:MM
+ **   %s  seconds since 1970-01-01
+ **   %S  seconds 00-59
+-**   %w  day of week 0-6  Sunday==0
+-**   %W  week of year 00-53
++**   %T  time as HH:MM:SS
++**   %u  day of week 1-7  Monday==1, Sunday==7
++**   %w  day of week 0-6  Sunday==0, Monday==1
++**   %U  week of year 00-53  (First Sunday is start of week 01)
++**   %V  week of year 01-53  (First week containing Thursday is week 01)
++**   %W  week of year 00-53  (First Monday is start of week 01)
+ **   %Y  year 0000-9999
+ **   %%  %
+ */
+@@ -1288,7 +1427,7 @@ static void strftimeFunc(
+         sqlite3_str_appendf(&sRes, cf=='d' ? "%02d" : "%2d", x.D);
+         break;
+       }
+-      case 'f': {
++      case 'f': {  /* Fractional seconds.  (Non-standard) */
+         double s = x.s;
+         if( s>59.999 ) s = 59.999;
+         sqlite3_str_appendf(&sRes, "%06.3f", s);
+@@ -1298,6 +1437,21 @@ static void strftimeFunc(
+         sqlite3_str_appendf(&sRes, "%04d-%02d-%02d", x.Y, x.M, x.D);
+         break;
+       }
++      case 'G': /* Fall thru */
++      case 'g': {
++        DateTime y = x;
++        assert( y.validJD );
++        /* Move y so that it is the Thursday in the same week as x */
++        y.iJD += (3 - daysAfterMonday(&x))*86400000;
++        y.validYMD = 0;
++        computeYMD(&y);
++        if( cf=='g' ){
++          sqlite3_str_appendf(&sRes, "%02d", y.Y%100);
++        }else{
++          sqlite3_str_appendf(&sRes, "%04d", y.Y);
++        }
++        break;
++      }
+       case 'H':
+       case 'k': {
+         sqlite3_str_appendf(&sRes, cf=='H' ? "%02d" : "%2d", x.h);
+@@ -1311,25 +1465,11 @@ static void strftimeFunc(
+         sqlite3_str_appendf(&sRes, cf=='I' ? "%02d" : "%2d", h);
+         break;
+       }
+-      case 'W': /* Fall thru */
+-      case 'j': {
+-        int nDay;             /* Number of days since 1st day of year */
+-        DateTime y = x;
+-        y.validJD = 0;
+-        y.M = 1;
+-        y.D = 1;
+-        computeJD(&y);
+-        nDay = (int)((x.iJD-y.iJD+43200000)/86400000);
+-        if( cf=='W' ){
+-          int wd;   /* 0=Monday, 1=Tuesday, ... 6=Sunday */
+-          wd = (int)(((x.iJD+43200000)/86400000)%7);
+-          sqlite3_str_appendf(&sRes,"%02d",(nDay+7-wd)/7);
+-        }else{
+-          sqlite3_str_appendf(&sRes,"%03d",nDay+1);
+-        }
++      case 'j': {  /* Day of year.  Jan01==1, Jan02==2, and so forth */
++        sqlite3_str_appendf(&sRes,"%03d",daysAfterJan01(&x)+1);
+         break;
+       }
+-      case 'J': {
++      case 'J': {  /* Julian day number.  (Non-standard) */
+         sqlite3_str_appendf(&sRes,"%.16g",x.iJD/86400000.0);
+         break;
+       }
+@@ -1372,13 +1512,33 @@ static void strftimeFunc(
+         sqlite3_str_appendf(&sRes,"%02d:%02d:%02d", x.h, x.m, (int)x.s);
+         break;
+       }
+-      case 'u': /* Fall thru */
+-      case 'w': {
+-        char c = (char)(((x.iJD+129600000)/86400000) % 7) + '0';
++      case 'u':    /* Day of week.  1 to 7.  Monday==1, Sunday==7 */
++      case 'w': {  /* Day of week.  0 to 6.  Sunday==0, Monday==1 */
++        char c = (char)daysAfterSunday(&x) + '0';
+         if( c=='0' && cf=='u' ) c = '7';
+         sqlite3_str_appendchar(&sRes, 1, c);
+         break;
+       }
++      case 'U': {  /* Week num. 00-53. First Sun of the year is week 01 */
++        sqlite3_str_appendf(&sRes,"%02d",
++              (daysAfterJan01(&x)-daysAfterSunday(&x)+7)/7);
++        break;
++      }
++      case 'V': {  /* Week num. 01-53. First week with a Thur is week 01 */
++        DateTime y = x;
++        /* Adjust y so that is the Thursday in the same week as x */
++        assert( y.validJD );
++        y.iJD += (3 - daysAfterMonday(&x))*86400000;
++        y.validYMD = 0;
++        computeYMD(&y);
++        sqlite3_str_appendf(&sRes,"%02d", daysAfterJan01(&y)/7+1);
++        break;
++      }
++      case 'W': {  /* Week num. 00-53. First Mon of the year is week 01 */
++        sqlite3_str_appendf(&sRes,"%02d",
++           (daysAfterJan01(&x)-daysAfterMonday(&x)+7)/7);
++        break;
++      }
+       case 'Y': {
+         sqlite3_str_appendf(&sRes,"%04d",x.Y);
+         break;
+@@ -1525,9 +1685,7 @@ static void timediffFunc(
+     d1.iJD = d2.iJD - d1.iJD;
+     d1.iJD += (u64)1486995408 * (u64)100000;
+   }
+-  d1.validYMD = 0;
+-  d1.validHMS = 0;
+-  d1.validTZ = 0;
++  clearYMD_HMS_TZ(&d1);
+   computeYMD_HMS(&d1);
+   sqlite3StrAccumInit(&sRes, 0, 0, 0, 100);
+   sqlite3_str_appendf(&sRes, "%c%04d-%02d-%02d %02d:%02d:%06.3f",
+@@ -1596,6 +1754,36 @@ static void currentTimeFunc(
+ }
+ #endif
+ 
++#if !defined(SQLITE_OMIT_DATETIME_FUNCS) && defined(SQLITE_DEBUG)
++/*
++**   datedebug(...)
++**
++** This routine returns JSON that describes the internal DateTime object.
++** Used for debugging and testing only.  Subject to change.
++*/
++static void datedebugFunc(
++  sqlite3_context *context,
++  int argc,
++  sqlite3_value **argv
++){
++  DateTime x;
++  if( isDate(context, argc, argv, &x)==0 ){
++    char *zJson;
++    zJson = sqlite3_mprintf(
++      "{iJD:%lld,Y:%d,M:%d,D:%d,h:%d,m:%d,tz:%d,"
++      "s:%.3f,validJD:%d,validYMS:%d,validHMS:%d,"
++      "nFloor:%d,rawS:%d,isError:%d,useSubsec:%d,"
++      "isUtc:%d,isLocal:%d}",
++      x.iJD, x.Y, x.M, x.D, x.h, x.m, x.tz,
++      x.s, x.validJD, x.validYMD, x.validHMS,
++      x.nFloor, x.rawS, x.isError, x.useSubsec,
++      x.isUtc, x.isLocal);
++    sqlite3_result_text(context, zJson, -1, sqlite3_free);
++  }
++}
++#endif /* !SQLITE_OMIT_DATETIME_FUNCS && SQLITE_DEBUG */
++
++
+ /*
+ ** This function registered all of the above C functions as SQL
+ ** functions.  This should be the only routine in this file with
+@@ -1611,6 +1799,9 @@ void sqlite3RegisterDateTimeFunctions(void){
+     PURE_DATE(datetime,         -1, 0, 0, datetimeFunc  ),
+     PURE_DATE(strftime,         -1, 0, 0, strftimeFunc  ),
+     PURE_DATE(timediff,          2, 0, 0, timediffFunc  ),
++#ifdef SQLITE_DEBUG
++    PURE_DATE(datedebug,        -1, 0, 0, datedebugFunc ),
++#endif
+     DFUNCTION(current_time,      0, 0, 0, ctimeFunc     ),
+     DFUNCTION(current_timestamp, 0, 0, 0, ctimestampFunc),
+     DFUNCTION(current_date,      0, 0, 0, cdateFunc     ),

sqlite3/download.sh

@@ -3,7 +3,7 @@ set -euo pipefail
 
 cd -P -- "$(dirname -- "$0")"
 
-curl -#OL "https://sqlite.org/2024/sqlite-amalgamation-3450100.zip"
+curl -#OL "https://sqlite.org/2024/sqlite-amalgamation-3450200.zip"
 unzip -d . sqlite-amalgamation-*.zip
 mv sqlite-amalgamation-*/sqlite3* .
 rm -rf sqlite-amalgamation-*
@@ -12,25 +12,25 @@ cat *.patch | patch --no-backup-if-mismatch
 
 mkdir -p ext/
 cd ext/
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.1/ext/misc/anycollseq.c"
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.1/ext/misc/base64.c"
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.1/ext/misc/decimal.c"
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.1/ext/misc/ieee754.c"
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.1/ext/misc/regexp.c"
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.1/ext/misc/series.c"
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.1/ext/misc/uint.c"
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.1/ext/misc/uuid.c"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.3/ext/misc/anycollseq.c"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.3/ext/misc/base64.c"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.3/ext/misc/decimal.c"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.3/ext/misc/ieee754.c"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.3/ext/misc/regexp.c"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.3/ext/misc/series.c"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.3/ext/misc/uint.c"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.3/ext/misc/uuid.c"
 cd ~-
 
 cd ../vfs/tests/mptest/testdata/
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.1/mptest/mptest.c"
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.1/mptest/config01.test"
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.1/mptest/config02.test"
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.1/mptest/crash01.test"
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.1/mptest/crash02.subtest"
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.1/mptest/multiwrite01.test"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.3/mptest/mptest.c"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.3/mptest/config01.test"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.3/mptest/config02.test"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.3/mptest/crash01.test"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.3/mptest/crash02.subtest"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.3/mptest/multiwrite01.test"
 cd ~-
 
 cd ../vfs/tests/speedtest1/testdata/
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.1/test/speedtest1.c"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.3/test/speedtest1.c"
 cd ~-

sqlite3/hooks.c

@@ -8,12 +8,16 @@ int go_busy_handler(void *, int);
 int go_commit_hook(void *);
 void go_rollback_hook(void *);
 void go_update_hook(void *, int, char const *, char const *, sqlite3_int64);
+int go_wal_hook(void *, sqlite3 *, const char *, int);
 
 int go_authorizer(void *, int, const char *, const char *, const char *,
                   const char *);
 
 void go_log(void *, int, const char *);
 
+unsigned int go_autovacuum_pages(void *, const char *, unsigned int,
+                                 unsigned int, unsigned int);
+
 void sqlite3_progress_handler_go(sqlite3 *db, int n) {
   sqlite3_progress_handler(db, n, go_progress_handler, /*arg=*/db);
 }
@@ -34,6 +38,10 @@ void sqlite3_update_hook_go(sqlite3 *db, bool enable) {
   sqlite3_update_hook(db, enable ? go_update_hook : NULL, /*arg=*/db);
 }
 
+void sqlite3_wal_hook_go(sqlite3 *db, bool enable) {
+  sqlite3_wal_hook(db, enable ? go_wal_hook : NULL, /*arg=*/NULL);
+}
+
 int sqlite3_set_authorizer_go(sqlite3 *db, bool enable) {
   return sqlite3_set_authorizer(db, enable ? go_authorizer : NULL, /*arg=*/db);
 }
@@ -41,4 +49,10 @@ int sqlite3_set_authorizer_go(sqlite3 *db, bool enable) {
 int sqlite3_config_log_go(bool enable) {
   return sqlite3_config(SQLITE_CONFIG_LOG, enable ? go_log : NULL,
                         /*arg=*/NULL);
+}
+
+int sqlite3_autovacuum_pages_go(sqlite3 *db, go_handle app) {
+  int rc = sqlite3_autovacuum_pages(db, go_autovacuum_pages, app, go_destroy);
+  if (rc) go_destroy(app);
+  return rc;
 }

sqlite3/include.h

@@ -5,7 +5,7 @@
 
 // https://github.com/JuliaLang/julia/blob/v1.9.4/src/julia.h#L67-L68
 #define container_of(ptr, type, member) \
-  ((type *)((char *)(ptr)-offsetof(type, member)))
+  ((type *)((char *)(ptr) - offsetof(type, member)))
 
 typedef void *go_handle;
 void go_destroy(go_handle);

sqlite3/isoweek.patch

@@ -1,185 +0,0 @@
-# ISO week date specifiers, backport from 3.46.
---- sqlite3.c.orig
-+++ sqlite3.c
-@@ -25340,21 +25340,82 @@
- }
- 
- /*
-+** Compute the number of days after the most recent January 1.
-+**
-+** In other words, compute the zero-based day number for the
-+** current year:
-+**
-+**   Jan01 = 0,  Jan02 = 1, ..., Jan31 = 30, Feb01 = 31, ...
-+**   Dec31 = 364 or 365.
-+*/
-+static int daysAfterJan01(DateTime *pDate){
-+  DateTime jan01 = *pDate;
-+  assert( jan01.validYMD );
-+  assert( jan01.validHMS );
-+  assert( pDate->validJD );
-+  jan01.validJD = 0;
-+  jan01.M = 1;
-+  jan01.D = 1;
-+  computeJD(&jan01);
-+  return (int)((pDate->iJD-jan01.iJD+43200000)/86400000);
-+}
-+
-+/*
-+** Return the number of days after the most recent Monday.
-+**
-+** In other words, return the day of the week according
-+** to this code:
-+**
-+**   0=Monday, 1=Tuesday, 2=Wednesday, ..., 6=Sunday.
-+*/
-+static int daysAfterMonday(DateTime *pDate){
-+  assert( pDate->validJD );
-+  return (int)((pDate->iJD+43200000)/86400000) % 7;
-+}
-+
-+/*
-+** Return the number of days after the most recent Sunday.
-+**
-+** In other words, return the day of the week according
-+** to this code:
-+**
-+**   0=Sunday, 1=Monday, 2=Tues, ..., 6=Saturday
-+*/
-+static int daysAfterSunday(DateTime *pDate){
-+  assert( pDate->validJD );
-+  return (int)((pDate->iJD+129600000)/86400000) % 7;
-+}
-+
-+/*
- **    strftime( FORMAT, TIMESTRING, MOD, MOD, ...)
- **
- ** Return a string described by FORMAT.  Conversions as follows:
- **
--**   %d  day of month
-+**   %d  day of month  01-31
-+**   %e  day of month  1-31
- **   %f  ** fractional seconds  SS.SSS
-+**   %F  ISO date.  YYYY-MM-DD
-+**   %G  ISO year corresponding to %V 0000-9999.
-+**   %g  2-digit ISO year corresponding to %V 00-99
- **   %H  hour 00-24
--**   %j  day of year 000-366
-+**   %k  hour  0-24  (leading zero converted to space)
-+**   %I  hour 01-12
-+**   %j  day of year 001-366
- **   %J  ** julian day number
-+**   %l  hour  1-12  (leading zero converted to space)
- **   %m  month 01-12
- **   %M  minute 00-59
-+**   %p  "am" or "pm"
-+**   %P  "AM" or "PM"
-+**   %R  time as HH:MM
- **   %s  seconds since 1970-01-01
- **   %S  seconds 00-59
--**   %w  day of week 0-6  Sunday==0
--**   %W  week of year 00-53
-+**   %T  time as HH:MM:SS
-+**   %u  day of week 1-7  Monday==1, Sunday==7
-+**   %w  day of week 0-6  Sunday==0, Monday==1
-+**   %U  week of year 00-53  (First Sunday is start of week 01)
-+**   %V  week of year 01-53  (First week containing Thursday is week 01)
-+**   %W  week of year 00-53  (First Monday is start of week 01)
- **   %Y  year 0000-9999
- **   %%  %
- */
-@@ -25391,7 +25452,7 @@
-         sqlite3_str_appendf(&sRes, cf=='d' ? "%02d" : "%2d", x.D);
-         break;
-       }
--      case 'f': {
-+      case 'f': {  /* Fractional seconds.  (Non-standard) */
-         double s = x.s;
-         if( s>59.999 ) s = 59.999;
-         sqlite3_str_appendf(&sRes, "%06.3f", s);
-@@ -25401,6 +25462,21 @@
-         sqlite3_str_appendf(&sRes, "%04d-%02d-%02d", x.Y, x.M, x.D);
-         break;
-       }
-+      case 'G': /* Fall thru */
-+      case 'g': {
-+        DateTime y = x;
-+        assert( y.validJD );
-+        /* Move y so that it is the Thursday in the same week as x */
-+        y.iJD += (3 - daysAfterMonday(&x))*86400000;
-+        y.validYMD = 0;
-+        computeYMD(&y);
-+        if( cf=='g' ){
-+          sqlite3_str_appendf(&sRes, "%02d", y.Y%100);
-+        }else{
-+          sqlite3_str_appendf(&sRes, "%04d", y.Y);
-+        }
-+        break;
-+      }
-       case 'H':
-       case 'k': {
-         sqlite3_str_appendf(&sRes, cf=='H' ? "%02d" : "%2d", x.h);
-@@ -25414,25 +25490,11 @@
-         sqlite3_str_appendf(&sRes, cf=='I' ? "%02d" : "%2d", h);
-         break;
-       }
--      case 'W': /* Fall thru */
--      case 'j': {
--        int nDay;             /* Number of days since 1st day of year */
--        DateTime y = x;
--        y.validJD = 0;
--        y.M = 1;
--        y.D = 1;
--        computeJD(&y);
--        nDay = (int)((x.iJD-y.iJD+43200000)/86400000);
--        if( cf=='W' ){
--          int wd;   /* 0=Monday, 1=Tuesday, ... 6=Sunday */
--          wd = (int)(((x.iJD+43200000)/86400000)%7);
--          sqlite3_str_appendf(&sRes,"%02d",(nDay+7-wd)/7);
--        }else{
--          sqlite3_str_appendf(&sRes,"%03d",nDay+1);
--        }
-+      case 'j': {  /* Day of year.  Jan01==1, Jan02==2, and so forth */
-+        sqlite3_str_appendf(&sRes,"%03d",daysAfterJan01(&x)+1);
-         break;
-       }
--      case 'J': {
-+      case 'J': {  /* Julian day number.  (Non-standard) */
-         sqlite3_str_appendf(&sRes,"%.16g",x.iJD/86400000.0);
-         break;
-       }
-@@ -25475,11 +25537,31 @@
-         sqlite3_str_appendf(&sRes,"%02d:%02d:%02d", x.h, x.m, (int)x.s);
-         break;
-       }
--      case 'u': /* Fall thru */
--      case 'w': {
--        char c = (char)(((x.iJD+129600000)/86400000) % 7) + '0';
-+      case 'u':    /* Day of week.  1 to 7.  Monday==1, Sunday==7 */
-+      case 'w': {  /* Day of week.  0 to 6.  Sunday==0, Monday==1 */
-+        char c = (char)daysAfterSunday(&x) + '0';
-         if( c=='0' && cf=='u' ) c = '7';
-         sqlite3_str_appendchar(&sRes, 1, c);
-+        break;
-+      }
-+      case 'U': {  /* Week num. 00-53. First Sun of the year is week 01 */
-+        sqlite3_str_appendf(&sRes,"%02d",
-+              (daysAfterJan01(&x)-daysAfterSunday(&x)+7)/7);
-+        break;
-+      }
-+      case 'V': {  /* Week num. 01-53. First week with a Thur is week 01 */
-+        DateTime y = x;
-+        /* Adjust y so that is the Thursday in the same week as x */
-+        assert( y.validJD );
-+        y.iJD += (3 - daysAfterMonday(&x))*86400000;
-+        y.validYMD = 0;
-+        computeYMD(&y);
-+        sqlite3_str_appendf(&sRes,"%02d", daysAfterJan01(&y)/7+1);
-+        break;
-+      }
-+      case 'W': {  /* Week num. 00-53. First Mon of the year is week 01 */
-+        sqlite3_str_appendf(&sRes,"%02d",
-+           (daysAfterJan01(&x)-daysAfterMonday(&x)+7)/7);
-         break;
-       }
-       case 'Y': {

sqlite3/sqlite_cfg.h

@@ -9,10 +9,12 @@
 #define HAVE_INT16_T 1
 #define HAVE_INT32_T 1
 #define HAVE_INT64_T 1
+#define HAVE_INTPTR_T 1
 #define HAVE_UINT8_T 1
 #define HAVE_UINT16_T 1
 #define HAVE_UINT32_T 1
 #define HAVE_UINT64_T 1
+#define HAVE_UINTPTR_T 1
 #define HAVE_STDINT_H 1
 #define HAVE_INTTYPES_H 1
 
@@ -20,6 +22,8 @@
 #define HAVE_LOG10 1
 #define HAVE_ISNAN 1
 
+#define HAVE_STRCHRNUL 1
+
 #define HAVE_USLEEP 1
 #define HAVE_NANOSLEEP 1
 
@@ -37,6 +41,7 @@
 #define SQLITE_DEFAULT_WAL_SYNCHRONOUS 1
 #define SQLITE_LIKE_DOESNT_MATCH_BLOBS
 #define SQLITE_MAX_EXPR_DEPTH 0
+#define SQLITE_STRICT_SUBTYPE 1
 #define SQLITE_USE_ALLOCA
 #define SQLITE_OMIT_DEPRECATED
 #define SQLITE_OMIT_SHARED_CACHE
@@ -52,8 +57,8 @@
 #define SQLITE_ENABLE_ATOMIC_WRITE
 #define SQLITE_ENABLE_BATCH_ATOMIC_WRITE
 
-// Because WASM does not support shared memory,
-// SQLite disables WAL for WASM builds.
+// Because Wasm does not support shared memory,
+// SQLite disables WAL for Wasm builds.
 // We patch SQLite to use exclusive locking mode instead.
 // https://sqlite.org/wal.html#noshm
 #undef SQLITE_OMIT_WAL
@@ -68,18 +73,12 @@
 
 #define SQLITE_ENABLE_MATH_FUNCTIONS 1
 #define SQLITE_ENABLE_JSON1 1
-#define SQLITE_ENABLE_FTS3 1
-#define SQLITE_ENABLE_FTS3_PARENTHESIS 1
-#define SQLITE_ENABLE_FTS4 1
 #define SQLITE_ENABLE_FTS5 1
 #define SQLITE_ENABLE_RTREE 1
 #define SQLITE_ENABLE_GEOPOLY 1
 
 #define SQLITE_SOUNDEX
-
-// Session Extension
-// #define SQLITE_ENABLE_SESSION
-// #define SQLITE_ENABLE_PREUPDATE_HOOK
+#define SQLITE_UNTESTABLE
 
 // Implemented in vfs.c.
 int localtime_s(struct tm *const pTm, time_t const *const pTime);

sqlite3/time.c

@@ -27,63 +27,10 @@ static int time_collation(void *pArg, int nKey1, const void *pKey1, int nKey2,
   return rc;
 }
 
-static void json_time_func(sqlite3_context *context, int argc,
-                           sqlite3_value **argv) {
-  DateTime x;
-  if (isDate(context, argc, argv, &x)) return;
-  if (x.tzSet && x.tz) {
-    x.iJD += x.tz * 60000;
-    if (!validJulianDay(x.iJD)) return;
-    x.validYMD = 0;
-    x.validHMS = 0;
-  }
-  computeYMD_HMS(&x);
-
-  sqlite3 *db = sqlite3_context_db_handle(context);
-  sqlite3_str *res = sqlite3_str_new(db);
-
-  sqlite3_str_appendf(res, "%04d-%02d-%02dT%02d:%02d:%02d",  //
-                      x.Y, x.M, x.D,                         //
-                      x.h, x.m, (int)(x.iJD / 1000 % 60));
-
-  if (x.useSubsec) {
-    int rem = x.iJD % 1000;
-    if (rem) {
-      sqlite3_str_appendchar(res, 1, '.');
-      sqlite3_str_appendchar(res, 1, '0' + rem / 100);
-      if ((rem %= 100)) {
-        sqlite3_str_appendchar(res, 1, '0' + rem / 10);
-        if ((rem %= 10)) {
-          sqlite3_str_appendchar(res, 1, '0' + rem);
-        }
-      }
-    }
-  }
-
-  if (x.tz) {
-    sqlite3_str_appendf(res, "%+03d:%02d", x.tz / 60, abs(x.tz) % 60);
-  } else {
-    sqlite3_str_appendchar(res, 1, 'Z');
-  }
-
-  int rc = sqlite3_str_errcode(res);
-  if (rc) {
-    sqlite3_result_error_code(context, rc);
-    return;
-  }
-
-  int n = sqlite3_str_length(res);
-  sqlite3_result_text(context, sqlite3_str_finish(res), n, sqlite3_free);
-}
-
 int sqlite3_time_init(sqlite3 *db, char **pzErrMsg,
                       const sqlite3_api_routines *pApi) {
   sqlite3_create_collation_v2(db, "time", SQLITE_UTF8, /*arg=*/NULL,
                               time_collation,
                               /*destroy=*/NULL);
-  sqlite3_create_function_v2(
-      db, "json_time", /*nArg=*/-1,
-      SQLITE_UTF8 | SQLITE_DETERMINISTIC | SQLITE_INNOCUOUS, /*arg=*/NULL,
-      json_time_func, /*step=*/NULL, /*final=*/NULL, /*destroy=*/NULL);
   return SQLITE_OK;
 }

sqlite3/timezone.patch

@@ -1,45 +0,0 @@
-# Set UTC timezone, compute local offset.
---- sqlite3.c.orig
-+++ sqlite3.c
-@@ -340,6 +340,7 @@ static int setDateTimeToCurrent(sqlite3_context *context, DateTime *p){
-   p->iJD = sqlite3StmtCurrentTime(context);
-   if( p->iJD>0 ){
-     p->validJD = 1;
-+    p->tzSet = 1;
-     return 0;
-   }else{
-     return 1;
-@@ -355,6 +356,7 @@ static int setDateTimeToCurrent(sqlite3_context *context, DateTime *p){
- static void setRawDateNumber(DateTime *p, double r){
-   p->s = r;
-   p->rawS = 1;
-+  p->tzSet = 1;
-   if( r>=0.0 && r<5373484.5 ){
-     p->iJD = (sqlite3_int64)(r*86400000.0 + 0.5);
-     p->validJD = 1;
-@@ -731,7 +733,16 @@ static int parseModifier(
-       ** show local time.
-       */
-       if( sqlite3_stricmp(z, "localtime")==0 && sqlite3NotPureFunc(pCtx) ){
--        rc = toLocaltime(p, pCtx);
-+        if( p->tzSet!=0 || p->tz==0 ) {
-+          rc = toLocaltime(p, pCtx);
-+          i64 iOrigJD = p->iJD;
-+          p->tzSet = 0;
-+          computeJD(p);
-+          p->tz = (p->iJD-iOrigJD)/60000;
-+          if( abs(p->tz)>= 900 ) p->tz = 0;
-+        } else {
-+          rc = 0;
-+        }
-       }
-       break;
-     }
-@@ -781,6 +792,7 @@ static int parseModifier(
-           p->validJD = 1;
-           p->tzSet = 1;
-         }
-+        p->tz = 0;
-         rc = SQLITE_OK;
-       }
- #endif

sqlite3/vfs.c

@@ -5,15 +5,15 @@
 #include "include.h"
 #include "sqlite3.h"
 
-int go_localtime(struct tm *, sqlite3_int64);
 int go_vfs_find(const char *zVfsName);
+int go_localtime(struct tm *, sqlite3_int64);
 
 int go_randomness(sqlite3_vfs *, int nByte, char *zOut);
 int go_sleep(sqlite3_vfs *, int microseconds);
 int go_current_time_64(sqlite3_vfs *, sqlite3_int64 *);
 
 int go_open(sqlite3_vfs *, sqlite3_filename zName, sqlite3_file *, int flags,
-            int *pOutFlags);
+            int *pOutFlags, int *pOutVFS);
 int go_delete(sqlite3_vfs *, const char *zName, int syncDir);
 int go_access(sqlite3_vfs *, const char *zName, int flags, int *pResOut);
 int go_full_pathname(sqlite3_vfs *, const char *zName, int nOut, char *zOut);
@@ -32,29 +32,55 @@ int go_lock(sqlite3_file *, int eLock);
 int go_unlock(sqlite3_file *, int eLock);
 int go_check_reserved_lock(sqlite3_file *, int *pResOut);
 
+int go_shm_map(sqlite3_file *, int iPg, int pgsz, int, void volatile **);
+int go_shm_lock(sqlite3_file *, int offset, int n, int flags);
+int go_shm_unmap(sqlite3_file *, int deleteFlag);
+void go_shm_barrier(sqlite3_file *);
+
 static int go_open_wrapper(sqlite3_vfs *vfs, sqlite3_filename zName,
                            sqlite3_file *file, int flags, int *pOutFlags) {
-  static const sqlite3_io_methods os_io = {
-      .iVersion = 1,
-      .xClose = go_close,
-      .xRead = go_read,
-      .xWrite = go_write,
-      .xTruncate = go_truncate,
-      .xSync = go_sync,
-      .xFileSize = go_file_size,
-      .xLock = go_lock,
-      .xUnlock = go_unlock,
-      .xCheckReservedLock = go_check_reserved_lock,
-      .xFileControl = go_file_control,
-      .xSectorSize = go_sector_size,
-      .xDeviceCharacteristics = go_device_characteristics,
-  };
+  static const sqlite3_io_methods go_io[2] = {
+      {
+          .iVersion = 1,
+          .xClose = go_close,
+          .xRead = go_read,
+          .xWrite = go_write,
+          .xTruncate = go_truncate,
+          .xSync = go_sync,
+          .xFileSize = go_file_size,
+          .xLock = go_lock,
+          .xUnlock = go_unlock,
+          .xCheckReservedLock = go_check_reserved_lock,
+          .xFileControl = go_file_control,
+          .xSectorSize = go_sector_size,
+          .xDeviceCharacteristics = go_device_characteristics,
+      },
+      {
+          .iVersion = 2,
+          .xClose = go_close,
+          .xRead = go_read,
+          .xWrite = go_write,
+          .xTruncate = go_truncate,
+          .xSync = go_sync,
+          .xFileSize = go_file_size,
+          .xLock = go_lock,
+          .xUnlock = go_unlock,
+          .xCheckReservedLock = go_check_reserved_lock,
+          .xFileControl = go_file_control,
+          .xSectorSize = go_sector_size,
+          .xDeviceCharacteristics = go_device_characteristics,
+          .xShmMap = go_shm_map,
+          .xShmLock = go_shm_lock,
+          .xShmBarrier = go_shm_barrier,
+          .xShmUnmap = go_shm_unmap,
+      }};
+  int vfsID = 0;
   memset(file, 0, vfs->szOsFile);
-  int rc = go_open(vfs, zName, file, flags, pOutFlags);
+  int rc = go_open(vfs, zName, file, flags, pOutFlags, &vfsID);
   if (rc) {
     return rc;
   }
-  file->pMethods = &os_io;
+  file->pMethods = &go_io[vfsID];
   return SQLITE_OK;
 }
 

sqlite3/vtab.c

@@ -218,6 +218,7 @@ int sqlite3_vtab_config_go(sqlite3 *db, int op, int constraint) {
   return sqlite3_vtab_config(db, op, constraint);
 }
 
+static_assert(offsetof(struct sqlite3_vtab, zErrMsg) == 8, "Unexpected offset");
 static_assert(offsetof(struct go_module, base) == 4, "Unexpected offset");
 static_assert(offsetof(struct go_vtab, base) == 4, "Unexpected offset");
 static_assert(offsetof(struct go_cursor, base) == 4, "Unexpected offset");

stmt.go

@@ -120,7 +120,7 @@ func (s *Stmt) Status(op StmtStatus, reset bool) int {
 	}
 	r := s.c.call("sqlite3_stmt_status", uint64(s.handle),
 		uint64(op), i)
-	return int(r)
+	return int(int32(r))
 }
 
 // ClearBindings resets all bindings on the prepared statement.
@@ -137,7 +137,7 @@ func (s *Stmt) ClearBindings() error {
 func (s *Stmt) BindCount() int {
 	r := s.c.call("sqlite3_bind_parameter_count",
 		uint64(s.handle))
-	return int(r)
+	return int(int32(r))
 }
 
 // BindIndex returns the index of a parameter in the prepared statement
@@ -149,7 +149,7 @@ func (s *Stmt) BindIndex(name string) int {
 	namePtr := s.c.arena.string(name)
 	r := s.c.call("sqlite3_bind_parameter_index",
 		uint64(s.handle), uint64(namePtr))
-	return int(r)
+	return int(int32(r))
 }
 
 // BindName returns the name of a parameter in the prepared statement.
@@ -357,7 +357,7 @@ func (s *Stmt) BindValue(param int, value Value) error {
 func (s *Stmt) ColumnCount() int {
 	r := s.c.call("sqlite3_column_count",
 		uint64(s.handle))
-	return int(r)
+	return int(int32(r))
 }
 
 // ColumnName returns the name of the result column.
@@ -553,6 +553,14 @@ func (s *Stmt) ColumnValue(col int) Value {
 	}
 }
 
+// Columns populates result columns into the provided slice.
+// The slice must have [Stmt.ColumnCount] length.
+//
+// [INTEGER] columns will be retrieved as int64 values,
+// [FLOAT] as float64, [NULL] as nil,
+// [TEXT] as string, and [BLOB] as []byte.
+// Any []byte are owned by SQLite and may be invalidated by
+// subsequent calls to [Stmt] methods.
 func (s *Stmt) Columns(dest []any) error {
 	defer s.c.arena.mark()()
 	count := uint64(len(dest))

tests/backup_test.go

@@ -20,7 +20,7 @@ func TestBackup(t *testing.T) {
 		}
 		defer db.Close()
 
-		err = db.Exec(`CREATE TABLE IF NOT EXISTS users (id INT, name VARCHAR(10))`)
+		err = db.Exec(`CREATE TABLE users (id INT, name VARCHAR(10))`)
 		if err != nil {
 			t.Fatal(err)
 		}

tests/blob_test.go

@@ -22,7 +22,7 @@ func TestBlob(t *testing.T) {
 	}
 	defer db.Close()
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS test (col)`)
+	err = db.Exec(`CREATE TABLE test (col)`)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -97,7 +97,7 @@ func TestBlob_large(t *testing.T) {
 	}
 	defer db.Close()
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS test (col)`)
+	err = db.Exec(`CREATE TABLE test (col)`)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -158,7 +158,7 @@ func TestBlob_overflow(t *testing.T) {
 	}
 	defer db.Close()
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS test (col)`)
+	err = db.Exec(`CREATE TABLE test (col)`)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -217,7 +217,7 @@ func TestBlob_invalid(t *testing.T) {
 	}
 	defer db.Close()
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS test (col)`)
+	err = db.Exec(`CREATE TABLE test (col)`)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -242,7 +242,7 @@ func TestBlob_Write_readonly(t *testing.T) {
 	}
 	defer db.Close()
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS test (col)`)
+	err = db.Exec(`CREATE TABLE test (col)`)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -273,7 +273,7 @@ func TestBlob_Read_expired(t *testing.T) {
 	}
 	defer db.Close()
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS test (col)`)
+	err = db.Exec(`CREATE TABLE test (col)`)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -309,7 +309,7 @@ func TestBlob_Seek(t *testing.T) {
 	}
 	defer db.Close()
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS test (col)`)
+	err = db.Exec(`CREATE TABLE test (col)`)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -358,7 +358,7 @@ func TestBlob_Reopen(t *testing.T) {
 	}
 	defer db.Close()
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS test (col)`)
+	err = db.Exec(`CREATE TABLE test (col)`)
 	if err != nil {
 		t.Fatal(err)
 	}

tests/conn_test.go

@@ -6,12 +6,12 @@ import (
 	"math"
 	"os"
 	"path/filepath"
-	"reflect"
 	"strings"
 	"testing"
 
 	"github.com/ncruces/go-sqlite3"
 	_ "github.com/ncruces/go-sqlite3/embed"
+	_ "github.com/ncruces/go-sqlite3/vfs/memdb"
 )
 
 func TestConn_Open_dir(t *testing.T) {
@@ -111,41 +111,6 @@ func TestConn_Close_BUSY(t *testing.T) {
 	}
 }
 
-func TestConn_Pragma(t *testing.T) {
-	t.Parallel()
-
-	db, err := sqlite3.Open("file::memory:?_pragma=busy_timeout(1000)")
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer db.Close()
-
-	got, err := db.Pragma("busy_timeout")
-	if err != nil {
-		t.Fatal(err)
-	}
-	want := []string{"1000"}
-
-	if !reflect.DeepEqual(got, want) {
-		t.Errorf("got %v, want %v", got, want)
-	}
-
-	var serr *sqlite3.Error
-	_, err = db.Pragma("+")
-	if err == nil {
-		t.Error("want: error")
-	}
-	if !errors.As(err, &serr) {
-		t.Fatalf("got %T, want sqlite3.Error", err)
-	}
-	if rc := serr.Code(); rc != sqlite3.ERROR {
-		t.Errorf("got %d, want sqlite3.ERROR", rc)
-	}
-	if got := err.Error(); got != `sqlite3: SQL logic error: near "+": syntax error` {
-		t.Error("got message:", got)
-	}
-}
-
 func TestConn_SetInterrupt(t *testing.T) {
 	t.Parallel()
 
@@ -485,3 +450,35 @@ func TestConn_DBName(t *testing.T) {
 		t.Errorf("got %s", name)
 	}
 }
+
+func TestConn_AutoVacuumPages(t *testing.T) {
+	t.Parallel()
+
+	db, err := sqlite3.Open("file:test.db?vfs=memdb&_pragma=auto_vacuum(FULL)")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+
+	err = db.AutoVacuumPages(func(schema string, dbPages, freePages, bytesPerPage uint) uint {
+		return freePages
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = db.Exec(`CREATE TABLE test (col)`)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = db.Exec(`INSERT INTO test VALUES (zeroblob(1024*1024))`)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = db.Exec(`DROP TABLE test`)
+	if err != nil {
+		t.Fatal(err)
+	}
+}

tests/driver_test.go

@@ -27,7 +27,7 @@ func TestDriver(t *testing.T) {
 	defer conn.Close()
 
 	res, err := conn.ExecContext(ctx,
-		`CREATE TABLE IF NOT EXISTS users (id INT, name VARCHAR(10))`)
+		`CREATE TABLE users (id INT, name VARCHAR(10))`)
 	if err != nil {
 		t.Fatal(err)
 	}

tests/func_test.go

@@ -196,7 +196,7 @@ func TestAnyCollationNeeded(t *testing.T) {
 	}
 	defer db.Close()
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS users (id INT, name VARCHAR(10))`)
+	err = db.Exec(`CREATE TABLE users (id INT, name VARCHAR(10))`)
 	if err != nil {
 		t.Fatal(err)
 	}

tests/json_test.go

@@ -31,7 +31,7 @@ func TestJSON(t *testing.T) {
 	}
 	defer conn.Close()
 
-	_, err = conn.ExecContext(ctx, `CREATE TABLE IF NOT EXISTS test (col)`)
+	_, err = conn.ExecContext(ctx, `CREATE TABLE test (col)`)
 	if err != nil {
 		t.Fatal(err)
 	}

tests/parallel/parallel_test.go

@@ -12,9 +12,16 @@ import (
 
 	"github.com/ncruces/go-sqlite3"
 	_ "github.com/ncruces/go-sqlite3/embed"
+	"github.com/ncruces/go-sqlite3/vfs"
 	"github.com/ncruces/go-sqlite3/vfs/memdb"
+	"github.com/tetratelabs/wazero"
 )
 
+func TestMain(m *testing.M) {
+	sqlite3.RuntimeConfig = wazero.NewRuntimeConfig().WithMemoryLimitPages(1024)
+	os.Exit(m.Run())
+}
+
 func TestParallel(t *testing.T) {
 	var iter int
 	if testing.Short() {
@@ -32,6 +39,20 @@ func TestParallel(t *testing.T) {
 	testIntegrity(t, name)
 }
 
+func TestWAL(t *testing.T) {
+	if !vfs.SupportsSharedMemory {
+		t.Skip("skipping without shared memory")
+	}
+
+	name := "file:" +
+		filepath.Join(t.TempDir(), "test.db") +
+		"?_pragma=busy_timeout(10000)" +
+		"&_pragma=journal_mode(wal)" +
+		"&_pragma=synchronous(off)"
+	testParallel(t, name, 1000)
+	testIntegrity(t, name)
+}
+
 func TestMemory(t *testing.T) {
 	var iter int
 	if testing.Short() {

tests/stmt_test.go

@@ -19,7 +19,7 @@ func TestStmt(t *testing.T) {
 	}
 	defer db.Close()
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS test (col)`)
+	err = db.Exec(`CREATE TABLE test (col)`)
 	if err != nil {
 		t.Fatal(err)
 	}

tests/testdata/f2fs.sh

@@ -0,0 +1,21 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+cd -P -- "$(dirname -- "$0")"
+ROOT=../../
+
+if mountpoint -q f2fs/; then
+  sudo umount f2fs/
+fi
+
+mkdir -p f2fs/
+gunzip -c f2fs.img.gz > f2fs.img
+sudo mount -nv -o loop f2fs.img f2fs/
+mkdir -p f2fs/tmp/
+
+go test -c "$ROOT/tests" -coverpkg github.com/ncruces/go-sqlite3/...
+TMPDIR=f2fs/tmp/ ./tests.test -test.v -test.short -test.coverprofile cover.out
+go tool cover -html cover.out
+
+sudo umount f2fs/
+rm -r f2fs/ f2fs.img cover.out *.test

tests/time_test.go

@@ -146,8 +146,7 @@ func TestTimeFormat_Scanner(t *testing.T) {
 	}
 	defer conn.Close()
 
-	_, err = conn.ExecContext(ctx,
-		`CREATE TABLE IF NOT EXISTS test (col)`)
+	_, err = conn.ExecContext(ctx, `CREATE TABLE test (col)`)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -178,7 +177,7 @@ func TestDB_timeCollation(t *testing.T) {
 	}
 	defer db.Close()
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS times (tstamp COLLATE TIME)`)
+	err = db.Exec(`CREATE TABLE times (tstamp COLLATE TIME)`)
 	if err != nil {
 		t.Fatal(err)
 	}

tests/txn_test.go

@@ -22,7 +22,7 @@ func TestConn_Transaction_exec(t *testing.T) {
 	db.CommitHook(func() bool { return true })
 	db.UpdateHook(func(sqlite3.AuthorizerActionCode, string, string, int64) {})
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS test (col)`)
+	err = db.Exec(`CREATE TABLE test (col)`)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -95,7 +95,7 @@ func TestConn_Transaction_panic(t *testing.T) {
 	}
 	defer db.Close()
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS test (col)`)
+	err = db.Exec(`CREATE TABLE test (col)`)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -153,7 +153,7 @@ func TestConn_Transaction_interrupt(t *testing.T) {
 	}
 	defer db.Close()
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS test (col)`)
+	err = db.Exec(`CREATE TABLE test (col)`)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -255,7 +255,7 @@ func TestConn_Transaction_rollback(t *testing.T) {
 	}
 	defer db.Close()
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS test (col)`)
+	err = db.Exec(`CREATE TABLE test (col)`)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -301,7 +301,7 @@ func TestConn_Savepoint_exec(t *testing.T) {
 	}
 	defer db.Close()
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS test (col)`)
+	err = db.Exec(`CREATE TABLE test (col)`)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -369,7 +369,7 @@ func TestConn_Savepoint_panic(t *testing.T) {
 	}
 	defer db.Close()
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS test (col)`)
+	err = db.Exec(`CREATE TABLE test (col)`)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -426,7 +426,7 @@ func TestConn_Savepoint_interrupt(t *testing.T) {
 	}
 	defer db.Close()
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS test (col)`)
+	err = db.Exec(`CREATE TABLE test (col)`)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -506,7 +506,7 @@ func TestConn_Savepoint_rollback(t *testing.T) {
 	}
 	defer db.Close()
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS test (col)`)
+	err = db.Exec(`CREATE TABLE test (col)`)
 	if err != nil {
 		t.Fatal(err)
 	}

tests/wal_test.go

@@ -0,0 +1,96 @@
+package tests
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/ncruces/go-sqlite3"
+	"github.com/ncruces/go-sqlite3/vfs"
+)
+
+func TestWAL_enter_exit(t *testing.T) {
+	t.Parallel()
+
+	file := filepath.Join(t.TempDir(), "test.db")
+
+	db, err := sqlite3.Open(file)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+
+	err = db.Exec(`
+		CREATE TABLE test (col);
+		PRAGMA journal_mode=WAL;
+		SELECT * FROM test;
+		PRAGMA journal_mode=DELETE;
+		SELECT * FROM test;
+		PRAGMA journal_mode=WAL;
+		SELECT * FROM test;
+	`)
+	if err != nil {
+		t.Fatal(err)
+	}
+}
+
+func TestWAL_readonly(t *testing.T) {
+	if !vfs.SupportsSharedMemory {
+		t.Skip("skipping without shared memory")
+	}
+
+	t.Parallel()
+
+	tmp := filepath.Join(t.TempDir(), "test.db")
+	err := os.WriteFile(tmp, waldb, 0666)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	db, err := sqlite3.OpenFlags(tmp, sqlite3.OPEN_READONLY)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+
+	stmt, _, err := db.Prepare(`SELECT * FROM sqlite_master`)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer stmt.Close()
+
+	if stmt.Step() {
+		t.Error("want no rows")
+	}
+}
+
+func TestConn_WalCheckpoint(t *testing.T) {
+	t.Parallel()
+
+	file := filepath.Join(t.TempDir(), "test.db")
+
+	db, err := sqlite3.Open(file)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+
+	err = db.WalAutoCheckpoint(1000)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	db.WalHook(func(db *sqlite3.Conn, schema string, pages int) error {
+		log, ckpt, err := db.WalCheckpoint(schema, sqlite3.CHECKPOINT_FULL)
+		t.Log(log, ckpt, err)
+		return err
+	})
+
+	err = db.Exec(`
+		PRAGMA journal_mode=WAL;
+		CREATE TABLE test (col);
+	`)
+	if err != nil {
+		t.Fatal(err)
+	}
+}

txn.go

@@ -230,9 +230,6 @@ func (c *Conn) TxnState(schema string) TxnState {
 	return TxnState(r)
 }
 
-// Deprecated: renamed for consistency with [Conn.TxnState].
-type Tx = Txn
-
 // CommitHook registers a callback function to be invoked
 // whenever a transaction is committed.
 // Return true to allow the commit operation to continue normally.
@@ -260,7 +257,7 @@ func (c *Conn) RollbackHook(cb func()) {
 	c.rollback = cb
 }
 
-// RollbackHook registers a callback function to be invoked
+// UpdateHook registers a callback function to be invoked
 // whenever a row is updated, inserted or deleted in a rowid table.
 //
 // https://sqlite.org/c3ref/update_hook.html
@@ -273,13 +270,13 @@ func (c *Conn) UpdateHook(cb func(action AuthorizerActionCode, schema, table str
 	c.update = cb
 }
 
-func commitCallback(ctx context.Context, mod api.Module, pDB uint32) uint32 {
+func commitCallback(ctx context.Context, mod api.Module, pDB uint32) (rollback uint32) {
 	if c, ok := ctx.Value(connKey{}).(*Conn); ok && c.handle == pDB && c.commit != nil {
-		if ok := c.commit(); !ok {
-			return 1
+		if !c.commit() {
+			rollback = 1
 		}
 	}
-	return 0
+	return rollback
 }
 
 func rollbackCallback(ctx context.Context, mod api.Module, pDB uint32) {

util/fsutil/mode.go

@@ -1,3 +1,4 @@
+// Package fsutil implements filesystem utility functions.
 package fsutil
 
 import (

util/ioutil/seek.go

@@ -8,8 +8,8 @@ import (
 // SeekingReaderAt implements [io.ReaderAt]
 // through an underlying [io.ReadSeeker].
 type SeekingReaderAt struct {
-	l sync.Mutex
 	r io.ReadSeeker
+	l sync.Mutex
 }
 
 // NewSeekingReaderAt creates a new SeekingReaderAt.

util/osutil/open_windows.go

@@ -97,6 +97,10 @@ func syscallOpen(path string, mode int, perm uint32) (fd Handle, err error) {
 		// Necessary for opening directory handles.
 		attrs |= FILE_FLAG_BACKUP_SEMANTICS
 	}
+	if mode&O_SYNC != 0 {
+		const _FILE_FLAG_WRITE_THROUGH = 0x80000000
+		attrs |= _FILE_FLAG_WRITE_THROUGH
+	}
 	return CreateFile(pathp, access, sharemode, sa, createmode, attrs, 0)
 }
 

vfs/README.md

@@ -2,6 +2,79 @@
 
 This package implements the SQLite [OS Interface](https://sqlite.org/vfs.html) (aka VFS).
 
-It replaces the default SQLite VFS with a pure Go implementation.
+It replaces the default SQLite VFS with a **pure Go** implementation.
 
-It also exposes interfaces that should allow you to implement your own custom VFSes.
+It also exposes [interfaces](https://pkg.go.dev/github.com/ncruces/go-sqlite3/vfs#VFS)
+that should allow you to implement your own custom VFSes.
+
+Since it is a from scratch reimplementation,
+there are naturally some ways it deviates from the original.
+
+The main differences are [file locking](#file-locking) and [WAL mode](write-ahead-logging) support.
+
+### File Locking
+
+POSIX advisory locks, which SQLite uses on Unix, are
+[broken by design](https://sqlite.org/src/artifact/2e8b12?ln=1073-1161).
+
+On Linux, macOS and illumos, this module uses
+[OFD locks](https://www.gnu.org/software/libc/manual/html_node/Open-File-Description-Locks.html)
+to synchronize access to database files.
+OFD locks are fully compatible with POSIX advisory locks.
+
+On BSD Unixes, this module uses
+[BSD locks](https://man.freebsd.org/cgi/man.cgi?query=flock&sektion=2).
+On BSD Unixes, BSD locks are fully compatible with POSIX advisory locks.
+However, concurrency is reduced with BSD locks
+(`BEGIN IMMEDIATE` behaves the same as `BEGIN EXCLUSIVE`). 
+
+On Windows, this module uses `LockFileEx` and `UnlockFileEx`,
+like SQLite.
+
+On all other platforms, file locking is not supported, and you must use
+[`nolock=1`](https://sqlite.org/uri.html#urinolock)
+(or [`immutable=1`](https://sqlite.org/uri.html#uriimmutable))
+to open database files.
+
+To use the [`database/sql`](https://pkg.go.dev/database/sql) driver
+with `nolock=1` you must disable connection pooling by calling
+[`db.SetMaxOpenConns(1)`](https://pkg.go.dev/database/sql#DB.SetMaxOpenConns).
+
+You can use [`vfs.SupportsFileLocking`](https://pkg.go.dev/github.com/ncruces/go-sqlite3/vfs#SupportsFileLocking)
+to check if your platform supports file locking.
+
+### Write-Ahead Logging
+
+On 64-bit Linux, macOS and illumos, this module uses `mmap` to implement
+[shared-memory for the WAL-index](https://sqlite.org/wal.html#implementation_of_shared_memory_for_the_wal_index),
+like SQLite.
+
+To allow `mmap` to work, each connection needs to reserve up to 4GB of address space.\
+To limit the amount of address space each connection needs,
+use [`WithMemoryLimitPages`](../tests/parallel/parallel_test.go#L21).
+
+On all other platforms, [WAL](https://sqlite.org/wal.html) support is
+[limited](https://sqlite.org/wal.html#noshm).
+
+To work around this limitation, SQLite is [patched](sqlite3/locking_mode.patch)
+to automatically use `EXCLUSIVE` locking mode for WAL databases on such platforms.
+
+To use the [`database/sql`](https://pkg.go.dev/database/sql) driver
+with `EXCLUSIVE` locking mode you should disable connection pooling by calling
+[`db.SetMaxOpenConns(1)`](https://pkg.go.dev/database/sql#DB.SetMaxOpenConns).
+
+You can use [`vfs.SupportsSharedMemory`](https://pkg.go.dev/github.com/ncruces/go-sqlite3/vfs#SupportsSharedMemory)
+to check if your platform supports shared memory.
+
+### Batch-Atomic Write
+
+On 64-bit Linux, this module supports [batch-atomic writes](https://sqlite.org/cgi/src/technote/714)
+on the F2FS filesystem.
+
+### Build tags
+
+The VFS can be customized with a few build tags:
+- `sqlite3_flock` forces the use of BSD locks; it can be used on macOS to test the BSD locking implementation.
+- `sqlite3_nosys` prevents importing [`x/sys`](https://pkg.go.dev/golang.org/x/sys);
+  disables locking _and_ shared memory on all platforms.
+- `sqlite3_noshm` disables shared memory on all platforms.

vfs/api.go

@@ -80,6 +80,16 @@ type FileOverwrite interface {
 	Overwrite() error
 }
 
+// FilePersistentWAL extends File to implement the
+// SQLITE_FCNTL_PERSIST_WAL file control opcode.
+//
+// https://sqlite.org/c3ref/c_fcntl_begin_atomic_write.html#sqlitefcntlpersistwal
+type FilePersistentWAL interface {
+	File
+	PersistentWAL() bool
+	SetPersistentWAL(bool)
+}
+
 // FilePowersafeOverwrite extends File to implement the
 // SQLITE_FCNTL_POWERSAFE_OVERWRITE file control opcode.
 //
@@ -90,7 +100,7 @@ type FilePowersafeOverwrite interface {
 	SetPowersafeOverwrite(bool)
 }
 
-// FilePowersafeOverwrite extends File to implement the
+// FileCommitPhaseTwo extends File to implement the
 // SQLITE_FCNTL_COMMIT_PHASETWO file control opcode.
 //
 // https://sqlite.org/c3ref/c_fcntl_begin_atomic_write.html#sqlitefcntlcommitphasetwo

vfs/clear.go

@@ -1,9 +0,0 @@
-//go:build !go1.21
-
-package vfs
-
-func clear(b []byte) {
-	for i := range b {
-		b[i] = 0
-	}
-}

vfs/const.go

@@ -37,6 +37,10 @@ const (
 	_IOERR_CHECKRESERVEDLOCK _ErrorCode = util.IOERR_CHECKRESERVEDLOCK
 	_IOERR_LOCK              _ErrorCode = util.IOERR_LOCK
 	_IOERR_CLOSE             _ErrorCode = util.IOERR_CLOSE
+	_IOERR_SHMOPEN           _ErrorCode = util.IOERR_SHMOPEN
+	_IOERR_SHMSIZE           _ErrorCode = util.IOERR_SHMSIZE
+	_IOERR_SHMLOCK           _ErrorCode = util.IOERR_SHMLOCK
+	_IOERR_SHMMAP            _ErrorCode = util.IOERR_SHMMAP
 	_IOERR_SEEK              _ErrorCode = util.IOERR_SEEK
 	_IOERR_DELETE_NOENT      _ErrorCode = util.IOERR_DELETE_NOENT
 	_IOERR_BEGIN_ATOMIC      _ErrorCode = util.IOERR_BEGIN_ATOMIC
@@ -44,6 +48,7 @@ const (
 	_IOERR_ROLLBACK_ATOMIC   _ErrorCode = util.IOERR_ROLLBACK_ATOMIC
 	_CANTOPEN_FULLPATH       _ErrorCode = util.CANTOPEN_FULLPATH
 	_CANTOPEN_ISDIR          _ErrorCode = util.CANTOPEN_ISDIR
+	_READONLY_CANTINIT       _ErrorCode = util.READONLY_CANTINIT
 	_OK_SYMLINK              _ErrorCode = util.OK_SYMLINK
 )
 
@@ -213,3 +218,13 @@ const (
 	_FCNTL_CKSM_FILE             _FcntlOpcode = 41
 	_FCNTL_RESET_CACHE           _FcntlOpcode = 42
 )
+
+// https://sqlite.org/c3ref/c_shm_exclusive.html
+type _ShmFlag uint32
+
+const (
+	_SHM_UNLOCK    _ShmFlag = 1
+	_SHM_LOCK      _ShmFlag = 2
+	_SHM_SHARED    _ShmFlag = 4
+	_SHM_EXCLUSIVE _ShmFlag = 8
+)

vfs/file.go

@@ -1,6 +1,7 @@
 package vfs
 
 import (
+	"context"
 	"errors"
 	"io"
 	"io/fs"
@@ -11,6 +12,7 @@ import (
 	"syscall"
 
 	"github.com/ncruces/go-sqlite3/util/osutil"
+	"github.com/tetratelabs/wazero/api"
 )
 
 type vfsOS struct{}
@@ -125,10 +127,12 @@ func (vfsOS) OpenParams(name string, flags OpenFlag, params url.Values) (File, O
 
 type vfsFile struct {
 	*os.File
+	shm      vfsShm
 	lock     LockLevel
-	psow     bool
-	syncDir  bool
 	readOnly bool
+	keepWAL  bool
+	syncDir  bool
+	psow     bool
 }
 
 var (
@@ -136,9 +140,15 @@ var (
 	_ FileLockState          = &vfsFile{}
 	_ FileHasMoved           = &vfsFile{}
 	_ FileSizeHint           = &vfsFile{}
+	_ FilePersistentWAL      = &vfsFile{}
 	_ FilePowersafeOverwrite = &vfsFile{}
 )
 
+func (f *vfsFile) Close() error {
+	f.shm.Close()
+	return f.File.Close()
+}
+
 func (f *vfsFile) Sync(flags SyncFlag) error {
 	dataonly := (flags & SYNC_DATAONLY) != 0
 	fullsync := (flags & 0x0f) == SYNC_FULL
@@ -171,10 +181,14 @@ func (*vfsFile) SectorSize() int {
 }
 
 func (f *vfsFile) DeviceCharacteristics() DeviceCharacteristic {
-	if f.psow {
-		return IOCAP_POWERSAFE_OVERWRITE
+	var res DeviceCharacteristic
+	if osBatchAtomic(f.File) {
+		res |= IOCAP_BATCH_ATOMIC
 	}
-	return 0
+	if f.psow {
+		res |= IOCAP_POWERSAFE_OVERWRITE
+	}
+	return res
 }
 
 func (f *vfsFile) SizeHint(size int64) error {
@@ -198,4 +212,12 @@ func (f *vfsFile) HasMoved() (bool, error) {
 
 func (f *vfsFile) LockState() LockLevel            { return f.lock }
 func (f *vfsFile) PowersafeOverwrite() bool        { return f.psow }
+func (f *vfsFile) PersistentWAL() bool             { return f.keepWAL }
 func (f *vfsFile) SetPowersafeOverwrite(psow bool) { f.psow = psow }
+func (f *vfsFile) SetPersistentWAL(keepWAL bool)   { f.keepWAL = keepWAL }
+
+type fileShm interface {
+	shmMap(context.Context, api.Module, int32, int32, bool) (uint32, error)
+	shmLock(int32, int32, _ShmFlag) error
+	shmUnmap(bool)
+}

vfs/lock.go

@@ -1,7 +1,17 @@
+//go:build (linux || darwin || windows || freebsd || openbsd || netbsd || dragonfly || illumos) && !sqlite3_nosys
+
 package vfs
 
 import "github.com/ncruces/go-sqlite3/internal/util"
 
+// SupportsFileLocking is false on platforms that do not support file locking.
+// To open a database file on those platforms,
+// you need to use the [nolock] or [immutable] URI parameters.
+//
+// [nolock]: https://sqlite.org/uri.html#urinolock
+// [immutable]: https://sqlite.org/uri.html#uriimmutable
+const SupportsFileLocking = true
+
 const (
 	_PENDING_BYTE  = 0x40000000
 	_RESERVED_BYTE = (_PENDING_BYTE + 1)
@@ -65,14 +75,20 @@ func (f *vfsFile) Lock(lock LockLevel) error {
 		if f.lock <= LOCK_NONE || f.lock >= LOCK_EXCLUSIVE {
 			panic(util.AssertErr())
 		}
+		reserved := f.lock == LOCK_RESERVED
 		// A PENDING lock is needed before acquiring an EXCLUSIVE lock.
 		if f.lock < LOCK_PENDING {
-			if rc := osGetPendingLock(f.File); rc != _OK {
+			// If we're already RESERVED, we can block indefinitely,
+			// since only new readers may briefly hold the PENDING lock.
+			if rc := osGetPendingLock(f.File, reserved /* block */); rc != _OK {
 				return rc
 			}
 			f.lock = LOCK_PENDING
 		}
-		if rc := osGetExclusiveLock(f.File); rc != _OK {
+		// We already have PENDING, so we're just waiting for readers to leave.
+		// If we were RESERVED, we can wait for a little while, before invoking
+		// the busy handler; we will only do this once.
+		if rc := osGetExclusiveLock(f.File, reserved /* wait */); rc != _OK {
 			return rc
 		}
 		f.lock = LOCK_EXCLUSIVE
@@ -101,11 +117,9 @@ func (f *vfsFile) Unlock(lock LockLevel) error {
 
 	switch lock {
 	case LOCK_SHARED:
-		if rc := osDowngradeLock(f.File, f.lock); rc != _OK {
-			return rc
-		}
+		rc := osDowngradeLock(f.File, f.lock)
 		f.lock = LOCK_SHARED
-		return nil
+		return rc
 
 	case LOCK_NONE:
 		rc := osReleaseLock(f.File, f.lock)

vfs/lock_other.go

@@ -0,0 +1,23 @@
+//go:build !(linux || darwin || windows || freebsd || openbsd || netbsd || dragonfly || illumos) || sqlite3_nosys
+
+package vfs
+
+// SupportsFileLocking is false on platforms that do not support file locking.
+// To open a database file on those platforms,
+// you need to use the [nolock] or [immutable] URI parameters.
+//
+// [nolock]: https://sqlite.org/uri.html#urinolock
+// [immutable]: https://sqlite.org/uri.html#uriimmutable
+const SupportsFileLocking = false
+
+func (f *vfsFile) Lock(LockLevel) error {
+	return _IOERR_LOCK
+}
+
+func (f *vfsFile) Unlock(LockLevel) error {
+	return _IOERR_UNLOCK
+}
+
+func (f *vfsFile) CheckReservedLock() (bool, error) {
+	return false, _IOERR_CHECKRESERVEDLOCK
+}

vfs/lock_test.go

@@ -33,7 +33,7 @@ func Test_vfsLock(t *testing.T) {
 		pOutput = 32
 	)
 	mod := wazerotest.NewModule(wazerotest.NewMemory(wazerotest.PageSize))
-	ctx := util.NewContext(context.TODO())
+	ctx := util.NewContext(context.TODO(), false)
 
 	vfsFileRegister(ctx, mod, pFile1, &vfsFile{File: file1})
 	vfsFileRegister(ctx, mod, pFile2, &vfsFile{File: file2})

vfs/memdb/clear.go

@@ -1,10 +0,0 @@
-//go:build !go1.21
-
-package memdb
-
-func clear[T any](b []T) {
-	var zero T
-	for i := range b {
-		b[i] = zero
-	}
-}

vfs/memdb/memdb_test.go

@@ -21,7 +21,7 @@ func Test_wal(t *testing.T) {
 	}
 	defer db.Close()
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS users (id INT, name VARCHAR(10))`)
+	err = db.Exec(`CREATE TABLE users (id INT, name VARCHAR(10))`)
 	if err != nil {
 		t.Fatal(err)
 	}

vfs/os_bsd.go

@@ -19,38 +19,15 @@ func osUnlock(file *os.File, start, len int64) _ErrorCode {
 	return _OK
 }
 
-func osLock(file *os.File, how int, timeout time.Duration, def _ErrorCode) _ErrorCode {
-	before := time.Now()
-	var err error
-	for {
-		err = unix.Flock(int(file.Fd()), how)
-		if errno, _ := err.(unix.Errno); errno != unix.EAGAIN {
-			break
-		}
-		if timeout <= 0 || timeout < time.Since(before) {
-			break
-		}
-		time.Sleep(time.Millisecond)
-	}
+func osLock(file *os.File, how int, def _ErrorCode) _ErrorCode {
+	err := unix.Flock(int(file.Fd()), how)
 	return osLockErrorCode(err, def)
 }
 
-func osReadLock(file *os.File, start, len int64, timeout time.Duration) _ErrorCode {
-	return osLock(file, unix.LOCK_SH|unix.LOCK_NB, timeout, _IOERR_RDLOCK)
+func osReadLock(file *os.File, _ /*start*/, _ /*len*/ int64, _ /*timeout*/ time.Duration) _ErrorCode {
+	return osLock(file, unix.LOCK_SH|unix.LOCK_NB, _IOERR_RDLOCK)
 }
 
-func osWriteLock(file *os.File, start, len int64, timeout time.Duration) _ErrorCode {
-	return osLock(file, unix.LOCK_EX|unix.LOCK_NB, timeout, _IOERR_LOCK)
-}
-
-func osCheckLock(file *os.File, start, len int64) (bool, _ErrorCode) {
-	lock := unix.Flock_t{
-		Type:  unix.F_RDLCK,
-		Start: start,
-		Len:   len,
-	}
-	if unix.FcntlFlock(file.Fd(), unix.F_GETLK, &lock) != nil {
-		return false, _IOERR_CHECKRESERVEDLOCK
-	}
-	return lock.Type != unix.F_UNLCK, _OK
+func osWriteLock(file *os.File, _ /*start*/, _ /*len*/ int64, _ /*timeout*/ time.Duration) _ErrorCode {
+	return osLock(file, unix.LOCK_EX|unix.LOCK_NB, _IOERR_LOCK)
 }

vfs/os_darwin.go

@@ -14,7 +14,6 @@ const (
 	// https://github.com/apple/darwin-xnu/blob/main/bsd/sys/fcntl.h
 	_F_OFD_SETLK         = 90
 	_F_OFD_SETLKW        = 91
-	_F_OFD_GETLK         = 92
 	_F_OFD_SETLKWTIMEOUT = 93
 )
 
@@ -23,7 +22,7 @@ type flocktimeout_t struct {
 	timeout unix.Timespec
 }
 
-func osSync(file *os.File, fullsync, dataonly bool) error {
+func osSync(file *os.File, fullsync, _ /*dataonly*/ bool) error {
 	if fullsync {
 		return file.Sync()
 	}
@@ -75,9 +74,12 @@ func osLock(file *os.File, typ int16, start, len int64, timeout time.Duration, d
 		Len:   len,
 	}}
 	var err error
-	if timeout == 0 {
+	switch {
+	case timeout == 0:
 		err = unix.FcntlFlock(file.Fd(), _F_OFD_SETLK, &lock.fl)
-	} else {
+	case timeout < 0:
+		err = unix.FcntlFlock(file.Fd(), _F_OFD_SETLKW, &lock.fl)
+	default:
 		lock.timeout = unix.NsecToTimespec(int64(timeout / time.Nanosecond))
 		err = unix.FcntlFlock(file.Fd(), _F_OFD_SETLKWTIMEOUT, &lock.fl)
 	}
@@ -91,15 +93,3 @@ func osReadLock(file *os.File, start, len int64, timeout time.Duration) _ErrorCo
 func osWriteLock(file *os.File, start, len int64, timeout time.Duration) _ErrorCode {
 	return osLock(file, unix.F_WRLCK, start, len, timeout, _IOERR_LOCK)
 }
-
-func osCheckLock(file *os.File, start, len int64) (bool, _ErrorCode) {
-	lock := unix.Flock_t{
-		Type:  unix.F_RDLCK,
-		Start: start,
-		Len:   len,
-	}
-	if unix.FcntlFlock(file.Fd(), _F_OFD_GETLK, &lock) != nil {
-		return false, _IOERR_CHECKRESERVEDLOCK
-	}
-	return lock.Type != unix.F_UNLCK, _OK
-}

vfs/os_f2fs_linux.go

@@ -0,0 +1,34 @@
+//go:build (amd64 || arm64 || riscv64) && !sqlite3_nosys
+
+package vfs
+
+import (
+	"os"
+
+	"golang.org/x/sys/unix"
+)
+
+const (
+	_F2FS_IOC_START_ATOMIC_WRITE  = 62721
+	_F2FS_IOC_COMMIT_ATOMIC_WRITE = 62722
+	_F2FS_IOC_ABORT_ATOMIC_WRITE  = 62725
+	_F2FS_IOC_GET_FEATURES        = 2147808524
+	_F2FS_FEATURE_ATOMIC_WRITE    = 4
+)
+
+func osBatchAtomic(file *os.File) bool {
+	flags, err := unix.IoctlGetInt(int(file.Fd()), _F2FS_IOC_GET_FEATURES)
+	return err == nil && flags&_F2FS_FEATURE_ATOMIC_WRITE != 0
+}
+
+func (f *vfsFile) BeginAtomicWrite() error {
+	return unix.IoctlSetInt(int(f.Fd()), _F2FS_IOC_START_ATOMIC_WRITE, 0)
+}
+
+func (f *vfsFile) CommitAtomicWrite() error {
+	return unix.IoctlSetInt(int(f.Fd()), _F2FS_IOC_COMMIT_ATOMIC_WRITE, 0)
+}
+
+func (f *vfsFile) RollbackAtomicWrite() error {
+	return unix.IoctlSetInt(int(f.Fd()), _F2FS_IOC_ABORT_ATOMIC_WRITE, 0)
+}

vfs/os_linux.go

@@ -8,15 +8,9 @@ import (
 	"golang.org/x/sys/unix"
 )
 
-func osSync(file *os.File, fullsync, dataonly bool) error {
-	if dataonly {
-		_, _, err := unix.Syscall(unix.SYS_FDATASYNC, file.Fd(), 0, 0)
-		if err != 0 {
-			return err
-		}
-		return nil
-	}
-	return file.Sync()
+func osSync(file *os.File, _ /*fullsync*/, _ /*dataonly*/ bool) error {
+	// SQLite trusts Linux's fdatasync for all fsync's.
+	return unix.Fdatasync(int(file.Fd()))
 }
 
 func osAllocate(file *os.File, size int64) error {

vfs/os_nolock.go

@@ -1,41 +0,0 @@
-//go:build !(linux || darwin || windows || freebsd || openbsd || netbsd || dragonfly || illumos) || sqlite3_nosys
-
-package vfs
-
-import "os"
-
-// SupportsFileLocking is false on platforms that do not support file locking.
-// To open a database file in one such platform,
-// you need to use the [nolock] or [immutable] URI parameters.
-//
-// [nolock]: https://sqlite.org/uri.html#urinolock
-// [immutable]: https://sqlite.org/uri.html#uriimmutable
-const SupportsFileLocking = false
-
-func osGetSharedLock(file *os.File) _ErrorCode {
-	return _IOERR_RDLOCK
-}
-
-func osGetReservedLock(file *os.File) _ErrorCode {
-	return _IOERR_LOCK
-}
-
-func osGetPendingLock(file *os.File) _ErrorCode {
-	return _IOERR_LOCK
-}
-
-func osGetExclusiveLock(file *os.File) _ErrorCode {
-	return _IOERR_LOCK
-}
-
-func osDowngradeLock(file *os.File, state LockLevel) _ErrorCode {
-	return _IOERR_RDLOCK
-}
-
-func osReleaseLock(file *os.File, _ LockLevel) _ErrorCode {
-	return _IOERR_UNLOCK
-}
-
-func osCheckReservedLock(file *os.File) (bool, _ErrorCode) {
-	return false, _IOERR_CHECKRESERVEDLOCK
-}

vfs/os_ofd.go

@@ -3,6 +3,7 @@
 package vfs
 
 import (
+	"math/rand"
 	"os"
 	"time"
 
@@ -27,17 +28,24 @@ func osLock(file *os.File, typ int16, start, len int64, timeout time.Duration, d
 		Start: start,
 		Len:   len,
 	}
-	before := time.Now()
 	var err error
-	for {
+	switch {
+	case timeout == 0:
 		err = unix.FcntlFlock(file.Fd(), unix.F_OFD_SETLK, &lock)
-		if errno, _ := err.(unix.Errno); errno != unix.EAGAIN {
-			break
+	case timeout < 0:
+		err = unix.FcntlFlock(file.Fd(), unix.F_OFD_SETLKW, &lock)
+	default:
+		before := time.Now()
+		for {
+			err = unix.FcntlFlock(file.Fd(), unix.F_OFD_SETLK, &lock)
+			if errno, _ := err.(unix.Errno); errno != unix.EAGAIN {
+				break
+			}
+			if timeout < time.Since(before) {
+				break
+			}
+			osSleep(time.Duration(rand.Int63n(int64(time.Millisecond))))
 		}
-		if timeout <= 0 || timeout < time.Since(before) {
-			break
-		}
-		time.Sleep(time.Millisecond)
 	}
 	return osLockErrorCode(err, def)
 }
@@ -49,15 +57,3 @@ func osReadLock(file *os.File, start, len int64, timeout time.Duration) _ErrorCo
 func osWriteLock(file *os.File, start, len int64, timeout time.Duration) _ErrorCode {
 	return osLock(file, unix.F_WRLCK, start, len, timeout, _IOERR_LOCK)
 }
-
-func osCheckLock(file *os.File, start, len int64) (bool, _ErrorCode) {
-	lock := unix.Flock_t{
-		Type:  unix.F_RDLCK,
-		Start: start,
-		Len:   len,
-	}
-	if unix.FcntlFlock(file.Fd(), unix.F_OFD_GETLK, &lock) != nil {
-		return false, _IOERR_CHECKRESERVEDLOCK
-	}
-	return lock.Type != unix.F_UNLCK, _OK
-}

vfs/os_std_atomic.go

@@ -0,0 +1,9 @@
+//go:build !linux || !(amd64 || arm64 || riscv64) || sqlite3_nosys
+
+package vfs
+
+import "os"
+
+func osBatchAtomic(*os.File) bool {
+	return false
+}

vfs/os_std_sleep.go

@@ -0,0 +1,9 @@
+//go:build !windows || sqlite3_nosys
+
+package vfs
+
+import "time"
+
+func osSleep(d time.Duration) {
+	time.Sleep(d)
+}

vfs/os_std_sync.go

@@ -4,6 +4,6 @@ package vfs
 
 import "os"
 
-func osSync(file *os.File, fullsync, dataonly bool) error {
+func osSync(file *os.File, _ /*fullsync*/, _ /*dataonly*/ bool) error {
 	return file.Sync()
 }

vfs/os_unix_lock.go

@@ -9,17 +9,9 @@ import (
 	"golang.org/x/sys/unix"
 )
 
-// SupportsFileLocking is false on platforms that do not support file locking.
-// To open a database file in one such platform,
-// you need to use the [nolock] or [immutable] URI parameters.
-//
-// [nolock]: https://sqlite.org/uri.html#urinolock
-// [immutable]: https://sqlite.org/uri.html#uriimmutable
-const SupportsFileLocking = true
-
 func osGetSharedLock(file *os.File) _ErrorCode {
 	// Test the PENDING lock before acquiring a new SHARED lock.
-	if pending, _ := osCheckLock(file, _PENDING_BYTE, 1); pending {
+	if lock, _ := osGetLock(file, _PENDING_BYTE, 1); lock == unix.F_WRLCK {
 		return _BUSY
 	}
 	// Acquire the SHARED lock.
@@ -31,14 +23,22 @@ func osGetReservedLock(file *os.File) _ErrorCode {
 	return osWriteLock(file, _RESERVED_BYTE, 1, 0)
 }
 
-func osGetPendingLock(file *os.File) _ErrorCode {
+func osGetPendingLock(file *os.File, block bool) _ErrorCode {
+	var timeout time.Duration
+	if block {
+		timeout = -1
+	}
 	// Acquire the PENDING lock.
-	return osWriteLock(file, _PENDING_BYTE, 1, 0)
+	return osWriteLock(file, _PENDING_BYTE, 1, timeout)
 }
 
-func osGetExclusiveLock(file *os.File) _ErrorCode {
+func osGetExclusiveLock(file *os.File, wait bool) _ErrorCode {
+	var timeout time.Duration
+	if wait {
+		timeout = time.Millisecond
+	}
 	// Acquire the EXCLUSIVE lock.
-	return osWriteLock(file, _SHARED_FIRST, _SHARED_SIZE, time.Millisecond)
+	return osWriteLock(file, _SHARED_FIRST, _SHARED_SIZE, timeout)
 }
 
 func osDowngradeLock(file *os.File, state LockLevel) _ErrorCode {
@@ -64,7 +64,20 @@ func osReleaseLock(file *os.File, _ LockLevel) _ErrorCode {
 
 func osCheckReservedLock(file *os.File) (bool, _ErrorCode) {
 	// Test the RESERVED lock.
-	return osCheckLock(file, _RESERVED_BYTE, 1)
+	lock, rc := osGetLock(file, _RESERVED_BYTE, 1)
+	return lock == unix.F_WRLCK, rc
+}
+
+func osGetLock(file *os.File, start, len int64) (int16, _ErrorCode) {
+	lock := unix.Flock_t{
+		Type:  unix.F_WRLCK,
+		Start: start,
+		Len:   len,
+	}
+	if unix.FcntlFlock(file.Fd(), unix.F_GETLK, &lock) != nil {
+		return 0, _IOERR_CHECKRESERVEDLOCK
+	}
+	return lock.Type, _OK
 }
 
 func osLockErrorCode(err error, def _ErrorCode) _ErrorCode {

vfs/os_windows.go

@@ -3,24 +3,16 @@
 package vfs
 
 import (
+	"math/rand"
 	"os"
 	"time"
 
 	"golang.org/x/sys/windows"
 )
 
-// SupportsFileLocking is false on platforms that do not support file locking.
-// To open a database file in one such platform,
-// you need to use the [nolock] or [immutable] URI parameters.
-//
-// [nolock]: https://sqlite.org/uri.html#urinolock
-// [immutable]: https://sqlite.org/uri.html#uriimmutable
-const SupportsFileLocking = true
-
 func osGetSharedLock(file *os.File) _ErrorCode {
 	// Acquire the PENDING lock temporarily before acquiring a new SHARED lock.
 	rc := osReadLock(file, _PENDING_BYTE, 1, 0)
-
 	if rc == _OK {
 		// Acquire the SHARED lock.
 		rc = osReadLock(file, _SHARED_FIRST, _SHARED_SIZE, 0)
@@ -36,17 +28,27 @@ func osGetReservedLock(file *os.File) _ErrorCode {
 	return osWriteLock(file, _RESERVED_BYTE, 1, 0)
 }
 
-func osGetPendingLock(file *os.File) _ErrorCode {
+func osGetPendingLock(file *os.File, block bool) _ErrorCode {
+	var timeout time.Duration
+	if block {
+		timeout = -1
+	}
+
 	// Acquire the PENDING lock.
-	return osWriteLock(file, _PENDING_BYTE, 1, 0)
+	return osWriteLock(file, _PENDING_BYTE, 1, timeout)
 }
 
-func osGetExclusiveLock(file *os.File) _ErrorCode {
+func osGetExclusiveLock(file *os.File, wait bool) _ErrorCode {
+	var timeout time.Duration
+	if wait {
+		timeout = time.Millisecond
+	}
+
 	// Release the SHARED lock.
 	osUnlock(file, _SHARED_FIRST, _SHARED_SIZE)
 
 	// Acquire the EXCLUSIVE lock.
-	rc := osWriteLock(file, _SHARED_FIRST, _SHARED_SIZE, time.Millisecond)
+	rc := osWriteLock(file, _SHARED_FIRST, _SHARED_SIZE, timeout)
 
 	if rc != _OK {
 		// Reacquire the SHARED lock.
@@ -94,7 +96,15 @@ func osReleaseLock(file *os.File, state LockLevel) _ErrorCode {
 
 func osCheckReservedLock(file *os.File) (bool, _ErrorCode) {
 	// Test the RESERVED lock.
-	return osCheckLock(file, _RESERVED_BYTE, 1)
+	rc := osLock(file, 0, _RESERVED_BYTE, 1, 0, _IOERR_CHECKRESERVEDLOCK)
+	if rc == _BUSY {
+		return true, _OK
+	}
+	if rc == _OK {
+		// Release the RESERVED lock.
+		osUnlock(file, _RESERVED_BYTE, 1)
+	}
+	return false, rc
 }
 
 func osUnlock(file *os.File, start, len uint32) _ErrorCode {
@@ -110,51 +120,39 @@ func osUnlock(file *os.File, start, len uint32) _ErrorCode {
 }
 
 func osLock(file *os.File, flags, start, len uint32, timeout time.Duration, def _ErrorCode) _ErrorCode {
-	before := time.Now()
 	var err error
-	for {
-		err = windows.LockFileEx(windows.Handle(file.Fd()), flags,
-			0, len, 0, &windows.Overlapped{Offset: start})
-		if errno, _ := err.(windows.Errno); errno != windows.ERROR_LOCK_VIOLATION {
-			break
-		}
-		if timeout <= 0 || timeout < time.Since(before) {
-			break
-		}
-		if err := windows.TimeBeginPeriod(1); err != nil {
-			break
-		}
-		time.Sleep(time.Millisecond)
-		if err := windows.TimeEndPeriod(1); err != nil {
-			break
+	switch {
+	case timeout == 0:
+		err = osLockEx(file, flags|windows.LOCKFILE_FAIL_IMMEDIATELY, start, len)
+	case timeout < 0:
+		err = osLockEx(file, flags, start, len)
+	default:
+		before := time.Now()
+		for {
+			err = osLockEx(file, flags|windows.LOCKFILE_FAIL_IMMEDIATELY, start, len)
+			if errno, _ := err.(windows.Errno); errno != windows.ERROR_LOCK_VIOLATION {
+				break
+			}
+			if timeout < time.Since(before) {
+				break
+			}
+			osSleep(time.Duration(rand.Int63n(int64(time.Millisecond))))
 		}
 	}
 	return osLockErrorCode(err, def)
 }
 
+func osLockEx(file *os.File, flags, start, len uint32) error {
+	return windows.LockFileEx(windows.Handle(file.Fd()), flags,
+		0, len, 0, &windows.Overlapped{Offset: start})
+}
+
 func osReadLock(file *os.File, start, len uint32, timeout time.Duration) _ErrorCode {
-	return osLock(file,
-		windows.LOCKFILE_FAIL_IMMEDIATELY,
-		start, len, timeout, _IOERR_RDLOCK)
+	return osLock(file, 0, start, len, timeout, _IOERR_RDLOCK)
 }
 
 func osWriteLock(file *os.File, start, len uint32, timeout time.Duration) _ErrorCode {
-	return osLock(file,
-		windows.LOCKFILE_FAIL_IMMEDIATELY|windows.LOCKFILE_EXCLUSIVE_LOCK,
-		start, len, timeout, _IOERR_LOCK)
-}
-
-func osCheckLock(file *os.File, start, len uint32) (bool, _ErrorCode) {
-	rc := osLock(file,
-		windows.LOCKFILE_FAIL_IMMEDIATELY,
-		start, len, 0, _IOERR_CHECKRESERVEDLOCK)
-	if rc == _BUSY {
-		return true, _OK
-	}
-	if rc == _OK {
-		osUnlock(file, start, len)
-	}
-	return false, rc
+	return osLock(file, windows.LOCKFILE_EXCLUSIVE_LOCK, start, len, timeout, _IOERR_LOCK)
 }
 
 func osLockErrorCode(err error, def _ErrorCode) _ErrorCode {
@@ -173,3 +171,16 @@ func osLockErrorCode(err error, def _ErrorCode) _ErrorCode {
 	}
 	return def
 }
+
+func osSleep(d time.Duration) {
+	if d > 0 {
+		period := max(1, d/(5*time.Millisecond))
+		if period < 16 {
+			windows.TimeBeginPeriod(uint32(period))
+		}
+		time.Sleep(d)
+		if period < 16 {
+			windows.TimeEndPeriod(uint32(period))
+		}
+	}
+}

vfs/shm.go

@@ -0,0 +1,151 @@
+//go:build (darwin || linux || illumos) && (amd64 || arm64 || riscv64) && !sqlite3_flock && !sqlite3_noshm && !sqlite3_nosys
+
+package vfs
+
+import (
+	"context"
+	"io"
+	"os"
+
+	"github.com/ncruces/go-sqlite3/internal/util"
+	"github.com/tetratelabs/wazero/api"
+	"golang.org/x/sys/unix"
+)
+
+// SupportsSharedMemory is true on platforms that support shared memory.
+// To enable shared memory support on those platforms,
+// you need to set the appropriate [wazero.RuntimeConfig];
+// otherwise, [EXCLUSIVE locking mode] is activated automatically
+// to use [WAL without shared-memory].
+//
+// [WAL without shared-memory]: https://sqlite.org/wal.html#noshm
+// [EXCLUSIVE locking mode]: https://sqlite.org/pragma.html#pragma_locking_mode
+const SupportsSharedMemory = true
+
+type vfsShm struct {
+	*os.File
+	regions []*util.MappedRegion
+}
+
+const (
+	_SHM_NLOCK = 8
+	_SHM_BASE  = 120
+	_SHM_DMS   = _SHM_BASE + _SHM_NLOCK
+)
+
+func (f *vfsFile) shmMap(ctx context.Context, mod api.Module, id, size int32, extend bool) (uint32, error) {
+	// Ensure size is a multiple of the OS page size.
+	if int(size)&(unix.Getpagesize()-1) != 0 {
+		return 0, _IOERR_SHMMAP
+	}
+
+	if f.shm.File == nil {
+		var flag int
+		if f.readOnly {
+			flag = unix.O_RDONLY
+		} else {
+			flag = unix.O_RDWR
+		}
+		s, err := os.OpenFile(f.Name()+"-shm",
+			flag|unix.O_CREAT|unix.O_NOFOLLOW, 0666)
+		if err != nil {
+			return 0, _CANTOPEN
+		}
+		f.shm.File = s
+	}
+
+	// Dead man's switch.
+	if lock, rc := osGetLock(f.shm.File, _SHM_DMS, 1); rc != _OK {
+		return 0, _IOERR_LOCK
+	} else if lock == unix.F_WRLCK {
+		return 0, _BUSY
+	} else if lock == unix.F_UNLCK {
+		if f.readOnly {
+			return 0, _READONLY_CANTINIT
+		}
+		if rc := osWriteLock(f.shm.File, _SHM_DMS, 1, 0); rc != _OK {
+			return 0, rc
+		}
+		if err := f.shm.Truncate(0); err != nil {
+			return 0, _IOERR_SHMOPEN
+		}
+	}
+	if rc := osReadLock(f.shm.File, _SHM_DMS, 1, 0); rc != _OK {
+		return 0, rc
+	}
+
+	// Check if file is big enough.
+	s, err := f.shm.Seek(0, io.SeekEnd)
+	if err != nil {
+		return 0, _IOERR_SHMSIZE
+	}
+	if n := (int64(id) + 1) * int64(size); n > s {
+		if !extend {
+			return 0, nil
+		}
+		err := osAllocate(f.shm.File, n)
+		if err != nil {
+			return 0, _IOERR_SHMSIZE
+		}
+	}
+
+	var prot int
+	if f.readOnly {
+		prot = unix.PROT_READ
+	} else {
+		prot = unix.PROT_READ | unix.PROT_WRITE
+	}
+	r, err := util.MapRegion(ctx, mod, f.shm.File, int64(id)*int64(size), size, prot)
+	if err != nil {
+		return 0, err
+	}
+	f.shm.regions = append(f.shm.regions, r)
+	return r.Ptr, nil
+}
+
+func (f *vfsFile) shmLock(offset, n int32, flags _ShmFlag) error {
+	// Argument check.
+	if n <= 0 || offset < 0 || offset+n > _SHM_NLOCK {
+		panic(util.AssertErr())
+	}
+	switch flags {
+	case
+		_SHM_LOCK | _SHM_SHARED,
+		_SHM_LOCK | _SHM_EXCLUSIVE,
+		_SHM_UNLOCK | _SHM_SHARED,
+		_SHM_UNLOCK | _SHM_EXCLUSIVE:
+		//
+	default:
+		panic(util.AssertErr())
+	}
+	if n != 1 && flags&_SHM_EXCLUSIVE == 0 {
+		panic(util.AssertErr())
+	}
+
+	switch {
+	case flags&_SHM_UNLOCK != 0:
+		return osUnlock(f.shm.File, _SHM_BASE+int64(offset), int64(n))
+	case flags&_SHM_SHARED != 0:
+		return osReadLock(f.shm.File, _SHM_BASE+int64(offset), int64(n), 0)
+	case flags&_SHM_EXCLUSIVE != 0:
+		return osWriteLock(f.shm.File, _SHM_BASE+int64(offset), int64(n), 0)
+	default:
+		panic(util.AssertErr())
+	}
+}
+
+func (f *vfsFile) shmUnmap(delete bool) {
+	// Unmap regions.
+	for _, r := range f.shm.regions {
+		r.Unmap()
+	}
+	clear(f.shm.regions)
+	f.shm.regions = f.shm.regions[:0]
+
+	// Close the file.
+	if delete && f.shm.File != nil {
+		os.Remove(f.shm.Name())
+	}
+	f.shm.Close()
+	f.shm.File = nil
+}