Time collation tests.

README.md

@@ -18,6 +18,10 @@ embeds a build of SQLite into your application.
 
 ### Caveats
 
+This module replaces the SQLite [OS Interface](https://www.sqlite.org/vfs.html) (aka VFS)
+with a pure Go implementation.
+This has numerous benefits, but also comes with some caveats.
+
 #### Write-Ahead Logging
 
 Because WASM does not support shared memory,
@@ -30,8 +34,10 @@ For non-WAL databases, `NORMAL` locking mode can be activated with
 [`PRAGMA locking_mode=NORMAL`](https://www.sqlite.org/pragma.html#pragma_locking_mode).
 
 Because connection pooling is incompatible with `EXCLUSIVE` locking mode,
-the `database/sql` driver defaults to `NORMAL` locking mode,
-and WAL databases are not supported.
+the `database/sql` driver defaults to `NORMAL` locking mode.
+To open WAL databases, or use `EXCLUSIVE` locking mode,
+disable connection pooling by calling
+[`db.SetMaxOpenConns(1)`](https://pkg.go.dev/database/sql#DB.SetMaxOpenConns).
 
 #### Open File Description Locks
 
@@ -43,15 +49,14 @@ OFD locks are fully compatible with process-associated POSIX advisory locks,
 and are supported on Linux, macOS and illumos.
 As a work around for other Unixes, you can use [`nolock=1`](https://www.sqlite.org/uri.html).
 
+#### Testing
+
+The pure Go VFS is stress tested by running an unmodified build of SQLite's
+[mptest](https://github.com/sqlite/sqlite/blob/master/mptest/mptest.c)
+on Linux, macOS and Windows.
+
 ### Roadmap
 
-- [x] build SQLite using `zig cc --target=wasm32-wasi`
-- [x] `:memory:` databases
-- [x] port [`test_demovfs.c`](https://www.sqlite.org/src/doc/trunk/src/test_demovfs.c) to Go
-  - branch [`wasi`](https://github.com/ncruces/go-sqlite3/tree/wasi) uses `test_demovfs.c` directly
-- [x] design a nice API, enough for simple use cases
-- [x] provide a simple `database/sql` driver
-- [x] file locking, compatible with SQLite on macOS/Linux/Windows
 - [ ] advanced SQLite features
   - [x] nested transactions
   - [x] incremental BLOB I/O

backup.go

@@ -11,7 +11,7 @@ type Backup struct {
 
 // Backup backs up srcDB on the src connection to the "main" database in dstURI.
 //
-// Backup calls [Conn.Open] to open the SQLite database file dstURI,
+// Backup calls [Open] to open the SQLite database file dstURI,
 // and blocks until the entire backup is complete.
 // Use [Conn.BackupInit] for incremental backup.
 //
@@ -28,7 +28,7 @@ func (src *Conn) Backup(srcDB, dstURI string) error {
 
 // Restore restores dstDB on the dst connection from the "main" database in srcURI.
 //
-// Restore calls [Conn.Open] to open the SQLite database file srcURI,
+// Restore calls [Open] to open the SQLite database file srcURI,
 // and blocks until the entire restore is complete.
 //
 // https://www.sqlite.org/backup.html
@@ -48,7 +48,7 @@ func (dst *Conn) Restore(dstDB, srcURI string) error {
 
 // BackupInit initializes a backup operation to copy the content of one database into another.
 //
-// BackupInit calls [Conn.Open] to open the SQLite database file dstURI,
+// BackupInit calls [Open] to open the SQLite database file dstURI,
 // then initializes a backup that copies the contents of srcDB on the src connection
 // to the "main" database in dstURI.
 //

blob.go

@@ -25,6 +25,7 @@ var _ io.ReadWriteSeeker = &Blob{}
 //
 // https://www.sqlite.org/c3ref/blob_open.html
 func (c *Conn) OpenBlob(db, table, column string, row int64, write bool) (*Blob, error) {
+	c.checkInterrupt()
 	defer c.arena.reset()
 	blobPtr := c.arena.new(ptrlen)
 	dbPtr := c.arena.string(db)

conn.go

@@ -3,6 +3,7 @@ package sqlite3
 import (
 	"context"
 	"database/sql/driver"
+	"errors"
 	"fmt"
 	"net/url"
 	"runtime"
@@ -87,13 +88,19 @@ func (c *Conn) openDB(filename string, flags OpenFlag) (uint32, error) {
 			}
 		}
 
+		c.arena.reset()
 		pragmaPtr := c.arena.string(pragmas.String())
 		r := c.call(c.api.exec, uint64(handle), uint64(pragmaPtr), 0, 0, 0)
 		if err := c.module.error(r[0], handle, pragmas.String()); err != nil {
+			if errors.Is(err, ERROR) {
+				err = fmt.Errorf("sqlite3: invalid _pragma: %w", err)
+			}
 			c.closeDB(handle)
-			return 0, fmt.Errorf("sqlite3: invalid _pragma: %w", err)
+			return 0, err
 		}
 	}
+
+	c.call(c.api.timeCollation, uint64(handle))
 	return handle, nil
 }
 
@@ -119,6 +126,8 @@ func (c *Conn) Close() error {
 	}
 
 	c.SetInterrupt(context.Background())
+	c.pending.Close()
+	c.pending = nil
 
 	r := c.call(c.api.close, uint64(c.handle))
 	if err := c.error(r[0]); err != nil {
@@ -143,23 +152,6 @@ func (c *Conn) Exec(sql string) error {
 	return c.error(r[0])
 }
 
-// MustPrepare calls [Conn.Prepare] and panics on error,
-// a nil Stmt, or a non-empty tail.
-func (c *Conn) MustPrepare(sql string) *Stmt {
-	s, tail, err := c.PrepareFlags(sql, 0)
-	if err != nil {
-		panic(err)
-	}
-	if s == nil {
-		panic(emptyErr)
-	}
-	if !emptyStatement(tail) {
-		s.Close()
-		panic(tailErr)
-	}
-	return s
-}
-
 // Prepare calls [Conn.PrepareFlags] with no flags.
 func (c *Conn) Prepare(sql string) (stmt *Stmt, tail string, err error) {
 	return c.PrepareFlags(sql, 0)
@@ -247,26 +239,23 @@ func (c *Conn) SetInterrupt(ctx context.Context) (old context.Context) {
 		<-c.waiter             // Wait for it to finish.
 		c.waiter = nil
 	}
+	// Reset the pending statement.
+	if c.pending != nil {
+		c.pending.Reset()
+	}
 
 	old = c.interrupt
 	c.interrupt = ctx
 	if ctx == nil || ctx.Done() == nil {
-		// Finalize the uncompleted SQL statement.
-		if c.pending != nil {
-			c.pending.Close()
-			c.pending = nil
-		}
 		return old
 	}
 
 	// Creating an uncompleted SQL statement prevents SQLite from ignoring
 	// an interrupt that comes before any other statements are started.
 	if c.pending == nil {
-		c.pending = c.MustPrepare(`SELECT 1 UNION ALL SELECT 2`)
-		c.pending.Step()
-	} else {
-		c.pending.Reset()
+		c.pending, _, _ = c.Prepare(`SELECT 1 UNION ALL SELECT 2`)
 	}
+	c.pending.Step()
 
 	// Don't create the goroutine if we're already interrupted.
 	// This happens frequently while restoring to a previously interrupted state.
@@ -306,15 +295,18 @@ func (c *Conn) checkInterrupt() bool {
 // Pragma executes a PRAGMA statement and returns any results.
 //
 // https://www.sqlite.org/pragma.html
-func (c *Conn) Pragma(str string) []string {
-	stmt := c.MustPrepare(`PRAGMA ` + str)
+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
+	return pragmas, stmt.Close()
 }
 
 func (c *Conn) error(rc uint64, sql ...string) error {
@@ -333,6 +325,6 @@ type DriverConn interface {
 	driver.ExecerContext
 	driver.ConnPrepareContext
 
-	Savepoint() (release func(*error))
+	Savepoint() Savepoint
 	OpenBlob(db, table, column string, row int64, write bool) (*Blob, error)
 }

const.go

@@ -133,6 +133,7 @@ const (
 	CONSTRAINT_DATATYPE     ExtendedErrorCode = xErrorCode(CONSTRAINT) | (12 << 8)
 	NOTICE_RECOVER_WAL      ExtendedErrorCode = xErrorCode(NOTICE) | (1 << 8)
 	NOTICE_RECOVER_ROLLBACK ExtendedErrorCode = xErrorCode(NOTICE) | (2 << 8)
+	NOTICE_RBU              ExtendedErrorCode = xErrorCode(NOTICE) | (3 << 8)
 	WARNING_AUTOINDEX       ExtendedErrorCode = xErrorCode(WARNING) | (1 << 8)
 	AUTH_USER               ExtendedErrorCode = xErrorCode(AUTH) | (1 << 8)
 )
@@ -167,14 +168,6 @@ const (
 	OPEN_EXRESCODE     OpenFlag = 0x02000000 /* Extended result codes */
 )
 
-type _AccessFlag uint32
-
-const (
-	_ACCESS_EXISTS    _AccessFlag = 0
-	_ACCESS_READWRITE _AccessFlag = 1 /* Used by PRAGMA temp_store_directory */
-	_ACCESS_READ      _AccessFlag = 2 /* Unused */
-)
-
 // PrepareFlag is a flag that can be passed to [Conn.PrepareFlags].
 //
 // https://www.sqlite.org/c3ref/c_prepare_normalize.html
@@ -216,3 +209,19 @@ func (t Datatype) String() string {
 	}
 	return strconv.FormatUint(uint64(t), 10)
 }
+
+type _AccessFlag uint32
+
+const (
+	_ACCESS_EXISTS    _AccessFlag = 0
+	_ACCESS_READWRITE _AccessFlag = 1 /* Used by PRAGMA temp_store_directory */
+	_ACCESS_READ      _AccessFlag = 2 /* Unused */
+)
+
+type _SyncFlag uint32
+
+const (
+	_SYNC_NORMAL   _SyncFlag = 0x00002
+	_SYNC_FULL     _SyncFlag = 0x00003
+	_SYNC_DATAONLY _SyncFlag = 0x00010
+)

driver/driver.go

@@ -86,15 +86,17 @@ func (sqlite) Open(name string) (_ driver.Conn, err error) {
 }
 
 type conn struct {
-	conn     *sqlite3.Conn
-	txBegin  string
-	txCommit string
+	conn       *sqlite3.Conn
+	txBegin    string
+	txCommit   string
+	txRollback string
 }
 
 var (
 	// Ensure these interfaces are implemented:
 	_ driver.ExecerContext = conn{}
 	_ driver.ConnBeginTx   = conn{}
+	_ driver.Validator     = conn{}
 	_ sqlite3.DriverConn   = conn{}
 )
 
@@ -102,27 +104,49 @@ func (c conn) Close() error {
 	return c.conn.Close()
 }
 
+func (c conn) IsValid() (valid bool) {
+	r, err := c.conn.Pragma("locking_mode")
+	return err == nil && len(r) == 1 && r[0] == "normal"
+}
+
 func (c conn) Begin() (driver.Tx, error) {
 	return c.BeginTx(context.Background(), driver.TxOptions{})
 }
 
-func (c conn) BeginTx(ctx context.Context, opts driver.TxOptions) (driver.Tx, error) {
-	switch opts.Isolation {
-	default:
-		return nil, isolationErr
-	case driver.IsolationLevel(sql.LevelDefault):
-	case driver.IsolationLevel(sql.LevelSerializable):
-	}
-
+func (c conn) BeginTx(_ context.Context, opts driver.TxOptions) (driver.Tx, error) {
 	txBegin := c.txBegin
 	c.txCommit = `COMMIT`
+	c.txRollback = `ROLLBACK`
+
 	if opts.ReadOnly {
-		c.txCommit = `
-			ROLLBACK;
-			PRAGMA query_only=` + c.conn.Pragma("query_only")[0]
+		query_only, err := c.conn.Pragma("query_only")
+		if err != nil {
+			return nil, err
+		}
 		txBegin = `
 			BEGIN deferred;
 			PRAGMA query_only=on`
+		c.txCommit = `
+			ROLLBACK;
+			PRAGMA query_only=` + query_only[0]
+		c.txRollback = c.txCommit
+	}
+
+	switch opts.Isolation {
+	default:
+		return nil, isolationErr
+	case
+		driver.IsolationLevel(sql.LevelDefault),
+		driver.IsolationLevel(sql.LevelSerializable):
+		break
+	case driver.IsolationLevel(sql.LevelReadUncommitted):
+		read_uncommitted, err := c.conn.Pragma("read_uncommitted")
+		if err != nil {
+			return nil, err
+		}
+		txBegin += `; PRAGMA read_uncommitted=on`
+		c.txCommit += `; PRAGMA read_uncommitted=` + read_uncommitted[0]
+		c.txRollback += `; PRAGMA read_uncommitted=` + read_uncommitted[0]
 	}
 
 	err := c.conn.Exec(txBegin)
@@ -134,14 +158,14 @@ func (c conn) BeginTx(ctx context.Context, opts driver.TxOptions) (driver.Tx, er
 
 func (c conn) Commit() error {
 	err := c.conn.Exec(c.txCommit)
-	if err != nil {
+	if err != nil && !c.conn.GetAutocommit() {
 		c.Rollback()
 	}
 	return err
 }
 
 func (c conn) Rollback() error {
-	return c.conn.Exec(`ROLLBACK`)
+	return c.conn.Exec(c.txRollback)
 }
 
 func (c conn) Prepare(query string) (driver.Stmt, error) {
@@ -189,7 +213,7 @@ func (c conn) ExecContext(ctx context.Context, query string, args []driver.Named
 	}, nil
 }
 
-func (c conn) Savepoint() (release func(*error)) {
+func (c conn) Savepoint() sqlite3.Savepoint {
 	return c.conn.Savepoint()
 }
 

driver/driver_test.go

@@ -1,4 +1,3 @@
-// Package driver provides a database/sql driver for SQLite.
 package driver
 
 import (
@@ -134,7 +133,9 @@ func Test_BeginTx(t *testing.T) {
 	ctx, cancel := context.WithCancel(context.Background())
 	defer cancel()
 
-	db, err := sql.Open("sqlite3", filepath.Join(t.TempDir(), "test.db"))
+	db, err := sql.Open("sqlite3", "file:"+
+		filepath.ToSlash(filepath.Join(t.TempDir(), "test.db"))+
+		"?_txlock=exclusive&_pragma=busy_timeout(0)")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -145,6 +146,16 @@ func Test_BeginTx(t *testing.T) {
 		t.Error("want isolationErr")
 	}
 
+	tx, err := db.BeginTx(ctx, &sql.TxOptions{Isolation: sql.LevelReadUncommitted})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = tx.Rollback()
+	if err != nil {
+		t.Fatal(err)
+	}
+
 	tx1, err := db.BeginTx(ctx, &sql.TxOptions{ReadOnly: true})
 	if err != nil {
 		t.Fatal(err)

driver_test.go

@@ -48,7 +48,8 @@ func ExampleDriverConn() {
 
 	err = conn.Raw(func(driverConn any) error {
 		conn := driverConn.(sqlite3.DriverConn)
-		defer conn.Savepoint()(&err)
+		savept := conn.Savepoint()
+		defer savept.Release(&err)
 
 		blob, err := conn.OpenBlob("main", "test", "col", id, true)
 		if err != nil {

embed/README.md

@@ -0,0 +1,15 @@
+# Embeddable WASM build of SQLite
+
+This folder includes an embeddable WASM build of SQLite 3.41.0 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
+- FTS3/4/5
+- JSON
+- R*Tree
+- GeoPoly
+
+See the [configuration options](../sqlite3/sqlite_cfg.h).
+
+Built using [`zig`](https://ziglang.org/) version 0.10.1.

embed/build.sh

@@ -13,4 +13,4 @@ zig cc --target=wasm32-wasi -flto -g0 -Os \
 	-mbulk-memory -mreference-types \
 	-mnontrapping-fptoint -msign-ext \
 	-D_HAVE_SQLITE_CONFIG_H \
-	$(awk '{print "-Wl,--export="$0}' ../sqlite3/exports.txt)
+	$(awk '{print "-Wl,--export="$0}' exports.txt)

embed/exports.txt

@@ -46,4 +46,5 @@ sqlite3_backup_step
 sqlite3_backup_finish
 sqlite3_backup_remaining
 sqlite3_backup_pagecount
+sqlite3_time_collation
 sqlite3_interrupt_offset

embed/init.go

@@ -4,9 +4,6 @@
 // with an appropriate build of SQLite:
 //
 //	import _ "github.com/ncruces/go-sqlite3/embed"
-//
-// You can obtain this build of SQLite from:
-// https://github.com/ncruces/go-sqlite3/tree/main/embed
 package embed
 
 import (

error.go

@@ -202,8 +202,6 @@ const (
 	noFuncErr   = errorString("sqlite3: could not find function: ")
 	binaryErr   = errorString("sqlite3: no SQLite binary embed/set/loaded")
 	timeErr     = errorString("sqlite3: invalid time value")
-	emptyErr    = errorString("sqlite3: empty statement")
-	tailErr     = errorString("sqlite3: non-empty tail")
 	notImplErr  = errorString("sqlite3: not implemented")
 	whenceErr   = errorString("sqlite3: invalid whence")
 	offsetErr   = errorString("sqlite3: invalid offset")

error_test.go

@@ -1,7 +1,6 @@
 package sqlite3
 
 import (
-	"context"
 	"errors"
 	"strings"
 	"testing"
@@ -9,7 +8,7 @@ import (
 
 func Test_assertErr(t *testing.T) {
 	err := assertErr()
-	if s := err.Error(); !strings.HasPrefix(s, "sqlite3: assertion failed") || !strings.HasSuffix(s, "error_test.go:11)") {
+	if s := err.Error(); !strings.HasPrefix(s, "sqlite3: assertion failed") || !strings.HasSuffix(s, "error_test.go:10)") {
 		t.Errorf("got %q", s)
 	}
 }
@@ -120,10 +119,8 @@ func Test_ErrorCode_Error(t *testing.T) {
 	// Test all error codes.
 	for i := 0; i == int(ErrorCode(i)); i++ {
 		want := "sqlite3: "
-		r, _ := db.api.errstr.Call(context.TODO(), uint64(i))
-		if r != nil {
-			want += db.mem.readString(uint32(r[0]), _MAX_STRING)
-		}
+		r := db.call(db.api.errstr, uint64(i))
+		want += db.mem.readString(uint32(r[0]), _MAX_STRING)
 
 		got := ErrorCode(i).Error()
 		if got != want {
@@ -144,10 +141,8 @@ func Test_ExtendedErrorCode_Error(t *testing.T) {
 	// Test all extended error codes.
 	for i := 0; i == int(ExtendedErrorCode(i)); i++ {
 		want := "sqlite3: "
-		r, _ := db.api.errstr.Call(context.TODO(), uint64(i))
-		if r != nil {
-			want += db.mem.readString(uint32(r[0]), _MAX_STRING)
-		}
+		r := db.call(db.api.errstr, uint64(i))
+		want += db.mem.readString(uint32(r[0]), _MAX_STRING)
 
 		got := ExtendedErrorCode(i).Error()
 		if got != want {

example_test.go

@@ -26,7 +26,11 @@ func Example() {
 		log.Fatal(err)
 	}
 
-	stmt := db.MustPrepare(`SELECT id, name FROM users`)
+	stmt, _, err := db.Prepare(`SELECT id, name FROM users`)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer stmt.Close()
 
 	for stmt.Step() {
 		fmt.Println(stmt.ColumnInt(0), stmt.ColumnText(1))

module.go

@@ -155,6 +155,7 @@ func newModule(mod api.Module) (m *module, err error) {
 		backupFinish:    getFun("sqlite3_backup_finish"),
 		backupRemaining: getFun("sqlite3_backup_remaining"),
 		backupPageCount: getFun("sqlite3_backup_pagecount"),
+		timeCollation:   getFun("sqlite3_time_collation"),
 		interrupt:       getVal("sqlite3_interrupt_offset"),
 	}
 	if err != nil {
@@ -348,5 +349,6 @@ type sqliteAPI struct {
 	backupFinish    api.Function
 	backupRemaining api.Function
 	backupPageCount api.Function
+	timeCollation   api.Function
 	interrupt       uint32
 }

sqlite3/amalg.c

@@ -3,6 +3,8 @@
 #include "main.c"
 #include "os.c"
 #include "qsort.c"
+#include "time.c"
+
 #include "sqlite3.c"
 
 sqlite3_destructor_type malloc_destructor = &free;

sqlite3/time.c

@@ -0,0 +1,28 @@
+#include <string.h>
+
+#include "sqlite3.h"
+
+static int time_collation(void *pArg, int nKey1, const void *pKey1, int nKey2,
+                          const void *pKey2) {
+  // If keys are of different length, and both terminated by a Z,
+  // ignore the Z for collation purposes.
+  if (nKey1 && nKey2 && nKey1 != nKey2) {
+    const char *pK1 = (const char *)pKey1;
+    const char *pK2 = (const char *)pKey2;
+    if (pK1[nKey1 - 1] == 'Z' && pK2[nKey2 - 1] == 'Z') {
+      nKey1--;
+      nKey2--;
+    }
+  }
+
+  int n = nKey1 < nKey2 ? nKey1 : nKey2;
+  int rc = memcmp(pKey1, pKey2, n);
+  if (rc == 0) {
+    rc = nKey1 - nKey2;
+  }
+  return rc;
+}
+
+int sqlite3_time_collation(sqlite3 *db) {
+  return sqlite3_create_collation(db, "TIME", SQLITE_UTF8, 0, time_collation);
+}

tests/conn_test.go

@@ -202,59 +202,3 @@ func TestConn_Prepare_invalid(t *testing.T) {
 		t.Error("got message:", got)
 	}
 }
-
-func TestConn_MustPrepare_empty(t *testing.T) {
-	t.Parallel()
-
-	db, err := sqlite3.Open(":memory:")
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer db.Close()
-
-	defer func() { _ = recover() }()
-	_ = db.MustPrepare(``)
-	t.Error("want panic")
-}
-
-func TestConn_MustPrepare_tail(t *testing.T) {
-	t.Parallel()
-
-	db, err := sqlite3.Open(":memory:")
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer db.Close()
-
-	defer func() { _ = recover() }()
-	_ = db.MustPrepare(`SELECT 1; -- HERE`)
-	t.Error("want panic")
-}
-
-func TestConn_MustPrepare_invalid(t *testing.T) {
-	t.Parallel()
-
-	db, err := sqlite3.Open(":memory:")
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer db.Close()
-
-	defer func() { _ = recover() }()
-	_ = db.MustPrepare(`SELECT`)
-	t.Error("want panic")
-}
-
-func TestConn_Pragma(t *testing.T) {
-	t.Parallel()
-
-	db, err := sqlite3.Open(":memory:")
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer db.Close()
-
-	defer func() { _ = recover() }()
-	_ = db.Pragma("encoding=''")
-	t.Error("want panic")
-}

tests/time_test.go

@@ -40,7 +40,7 @@ func TestTimeFormat_Decode(t *testing.T) {
 	t.Parallel()
 
 	reference := time.Date(2013, 10, 7, 4, 23, 19, 120_000_000, time.FixedZone("", -4*3600))
-	reftime := time.Date(2000, 1, 1, 4, 23, 19, 120_000_000, time.FixedZone("", -4*3600))
+	refnodate := time.Date(2000, 01, 1, 4, 23, 19, 120_000_000, time.FixedZone("", -4*3600))
 
 	tests := []struct {
 		fmt       sqlite3.TimeFormat
@@ -89,14 +89,14 @@ func TestTimeFormat_Decode(t *testing.T) {
 		{sqlite3.TimeFormatAuto, "1381134199120000", reference, 0, false},
 		{sqlite3.TimeFormatAuto, "1381134199120000000", reference, 0, false},
 		{sqlite3.TimeFormatAuto, "2013-10-07 04:23:19.12-04:00", reference, 0, false},
-		{sqlite3.TimeFormatAuto, "04:23:19.12-04:00", reftime, 0, false},
+		{sqlite3.TimeFormatAuto, "04:23:19.12-04:00", refnodate, 0, false},
 		{sqlite3.TimeFormatAuto, "abc", time.Time{}, 0, true},
 		{sqlite3.TimeFormatAuto, false, time.Time{}, 0, true},
 
 		{sqlite3.TimeFormat3, "2013-10-07 04:23:19.12-04:00", reference, 0, false},
 		{sqlite3.TimeFormat3, "2013-10-07 08:23:19.12", reference, 0, false},
-		{sqlite3.TimeFormat9, "04:23:19.12-04:00", reftime, 0, false},
-		{sqlite3.TimeFormat9, "08:23:19.12", reftime, 0, false},
+		{sqlite3.TimeFormat9, "04:23:19.12-04:00", refnodate, 0, false},
+		{sqlite3.TimeFormat9, "08:23:19.12", refnodate, 0, false},
 		{sqlite3.TimeFormat3, false, time.Time{}, 0, true},
 		{sqlite3.TimeFormat9, false, time.Time{}, 0, true},
 
@@ -118,3 +118,52 @@ func TestTimeFormat_Decode(t *testing.T) {
 		})
 	}
 }
+
+func TestDB_timeCollation(t *testing.T) {
+	t.Parallel()
+
+	db, err := sqlite3.Open(":memory:")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+
+	err = db.Exec(`CREATE TABLE IF NOT EXISTS times (tstamp COLLATE TIME)`)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	stmt, _, err := db.Prepare(`INSERT INTO times VALUES (?), (?), (?)`)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer stmt.Close()
+
+	stmt.BindTime(1, time.Unix(0, 0).UTC(), sqlite3.TimeFormatDefault)
+	stmt.BindTime(2, time.Unix(0, -1).UTC(), sqlite3.TimeFormatDefault)
+	stmt.BindTime(3, time.Unix(0, +1).UTC(), sqlite3.TimeFormatDefault)
+	stmt.Step()
+
+	err = stmt.Close()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	stmt, _, err = db.Prepare(`SELECT tstamp FROM times ORDER BY tstamp`)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var t0 time.Time
+	for stmt.Step() {
+		t1 := stmt.ColumnTime(0, sqlite3.TimeFormatAuto)
+		if t0.After(t1) {
+			t.Errorf("got %v after %v", t0, t1)
+		}
+		t0 = t1
+	}
+	err = stmt.Close()
+	if err != nil {
+		t.Fatal(err)
+	}
+}

tests/tx_test.go

@@ -185,10 +185,10 @@ func TestConn_Transaction_interrupt(t *testing.T) {
 		t.Errorf("got %v, want sqlite3.INTERRUPT", err)
 	}
 
-	var nilErr error
-	tx.End(&nilErr)
-	if !errors.Is(nilErr, sqlite3.INTERRUPT) {
-		t.Errorf("got %v, want sqlite3.INTERRUPT", nilErr)
+	err = nil
+	tx.End(&err)
+	if !errors.Is(err, sqlite3.INTERRUPT) {
+		t.Errorf("got %v, want sqlite3.INTERRUPT", err)
 	}
 
 	db.SetInterrupt(context.Background())
@@ -210,6 +210,33 @@ func TestConn_Transaction_interrupt(t *testing.T) {
 	}
 }
 
+func TestConn_Transaction_interrupted(t *testing.T) {
+	t.Parallel()
+
+	db, err := sqlite3.Open(":memory:")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+
+	ctx, cancel := context.WithCancel(context.Background())
+	db.SetInterrupt(ctx)
+	cancel()
+
+	tx := db.Begin()
+
+	err = tx.Commit()
+	if !errors.Is(err, sqlite3.INTERRUPT) {
+		t.Errorf("got %v, want sqlite3.INTERRUPT", err)
+	}
+
+	err = nil
+	tx.End(&err)
+	if !errors.Is(err, sqlite3.INTERRUPT) {
+		t.Errorf("got %v, want sqlite3.INTERRUPT", err)
+	}
+}
+
 func TestConn_Transaction_rollback(t *testing.T) {
 	t.Parallel()
 
@@ -286,7 +313,7 @@ func TestConn_Savepoint_exec(t *testing.T) {
 	}
 
 	insert := func(succeed bool) (err error) {
-		defer db.Savepoint()(&err)
+		defer db.Savepoint().Release(&err)
 
 		err = db.Exec(`INSERT INTO test VALUES ('hello')`)
 		if err != nil {
@@ -344,7 +371,7 @@ func TestConn_Savepoint_panic(t *testing.T) {
 	}
 
 	panics := func() (err error) {
-		defer db.Savepoint()(&err)
+		defer db.Savepoint().Release(&err)
 
 		err = db.Exec(`INSERT INTO test VALUES ('hello')`)
 		if err != nil {
@@ -395,12 +422,12 @@ func TestConn_Savepoint_interrupt(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	release := db.Savepoint()
+	savept := db.Savepoint()
 	err = db.Exec(`INSERT INTO test VALUES (1)`)
 	if err != nil {
 		t.Fatal(err)
 	}
-	release(&err)
+	savept.Release(&err)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -408,19 +435,19 @@ func TestConn_Savepoint_interrupt(t *testing.T) {
 	ctx, cancel := context.WithCancel(context.Background())
 	db.SetInterrupt(ctx)
 
-	release1 := db.Savepoint()
+	savept1 := db.Savepoint()
 	err = db.Exec(`INSERT INTO test VALUES (2)`)
 	if err != nil {
 		t.Fatal(err)
 	}
-	release2 := db.Savepoint()
+	savept2 := db.Savepoint()
 	err = db.Exec(`INSERT INTO test VALUES (3)`)
 	if err != nil {
 		t.Fatal(err)
 	}
 
 	cancel()
-	db.Savepoint()(&err)
+	db.Savepoint().Release(&err)
 	if !errors.Is(err, sqlite3.INTERRUPT) {
 		t.Errorf("got %v, want sqlite3.INTERRUPT", err)
 	}
@@ -431,15 +458,15 @@ func TestConn_Savepoint_interrupt(t *testing.T) {
 	}
 
 	err = context.Canceled
-	release2(&err)
+	savept2.Release(&err)
 	if err != context.Canceled {
 		t.Fatal(err)
 	}
 
-	var nilErr error
-	release1(&nilErr)
-	if !errors.Is(nilErr, sqlite3.INTERRUPT) {
-		t.Errorf("got %v, want sqlite3.INTERRUPT", nilErr)
+	err = nil
+	savept1.Release(&err)
+	if !errors.Is(err, sqlite3.INTERRUPT) {
+		t.Errorf("got %v, want sqlite3.INTERRUPT", err)
 	}
 
 	db.SetInterrupt(context.Background())
@@ -475,7 +502,7 @@ func TestConn_Savepoint_rollback(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	release := db.Savepoint()
+	savept := db.Savepoint()
 	err = db.Exec(`INSERT INTO test VALUES (1)`)
 	if err != nil {
 		t.Fatal(err)
@@ -484,7 +511,7 @@ func TestConn_Savepoint_rollback(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	release(&err)
+	savept.Release(&err)
 	if err != nil {
 		t.Fatal(err)
 	}

time.go

@@ -62,13 +62,18 @@ const (
 // [TimeFormatDefault] and [TimeFormatAuto] encode using [time.RFC3339Nano],
 // with nanosecond accuracy, and preserving any timezone offset.
 //
-// This is the format used by the database/sql driver:
-// [database/sql.Row.Scan] is able to decode as [time.Time]
+// This is the format used by the [database/sql] driver:
+// [database/sql.Row.Scan] will decode as [time.Time]
 // values encoded with [time.RFC3339Nano].
 //
 // Time values encoded with [time.RFC3339Nano] cannot be sorted as strings
 // to produce a time-ordered sequence.
-// Use [TimeFormat7] for time-ordered encoding.
+//
+// Assuming that the time zones of the time values are the same (e.g., all in UTC),
+// and expressed using the same string (e.g., all "Z" or all "+00:00"),
+// use the TIME [collating sequence] to produce a time-ordered sequence.
+//
+// Otherwise, use [TimeFormat7] for time-ordered encoding.
 //
 // Formats [TimeFormat1] through [TimeFormat10]
 // convert time values to UTC before encoding.
@@ -78,6 +83,8 @@ const (
 // or an int64 for the other numeric formats.
 //
 // https://www.sqlite.org/lang_datefunc.html
+//
+// [collating sequence]: https://www.sqlite.org/datatype3.html#collating_sequences
 func (f TimeFormat) Encode(t time.Time) any {
 	switch f {
 	// Numeric formats
@@ -123,9 +130,9 @@ func (f TimeFormat) Encode(t time.Time) any {
 // [TimeFormatAuto] implements (and extends) the SQLite auto modifier.
 // Julian day numbers are safe to use for historical dates,
 // from 4712BC through 9999AD.
-// Unix timestamps (expressed in seconds, milliseconds, microseconds, or nanoseconds),
-// are safe to use for current events, from 1980 through at least 2260.
-// Unix timestamps before 1980 may be misinterpreted as julian day numbers,
+// Unix timestamps (expressed in seconds, milliseconds, microseconds, or nanoseconds)
+// are safe to use for current events, from at least 1980 through at least 2260.
+// Unix timestamps before 1980 and after 9999 may be misinterpreted as julian day numbers,
 // or have the wrong time unit.
 //
 // https://www.sqlite.org/lang_datefunc.html

tx.go

@@ -4,10 +4,14 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"math/rand"
 	"runtime"
+	"strconv"
 )
 
 // Tx is an in-progress database transaction.
+//
+// https://www.sqlite.org/lang_transaction.html
 type Tx struct {
 	c *Conn
 }
@@ -16,8 +20,9 @@ type Tx struct {
 //
 // https://www.sqlite.org/lang_transaction.html
 func (c *Conn) Begin() Tx {
-	err := c.Exec(`BEGIN DEFERRED`)
-	if err != nil && !errors.Is(err, INTERRUPT) {
+	// BEGIN even if interrupted.
+	err := c.txExecInterrupted(`BEGIN DEFERRED`)
+	if err != nil {
 		panic(err)
 	}
 	return Tx{c}
@@ -64,21 +69,22 @@ func (tx Tx) End(errp *error) {
 		defer panic(recovered)
 	}
 
-	if tx.c.GetAutocommit() {
-		// There is nothing to commit/rollback.
-		return
-	}
-
-	if *errp == nil && recovered == nil {
+	if (errp == nil || *errp == nil) && recovered == nil {
 		// Success path.
+		if tx.c.GetAutocommit() { // There is nothing to commit.
+			return
+		}
 		*errp = tx.Commit()
 		if *errp == nil {
 			return
 		}
-		// Possible interrupt, fall through to the error path.
+		// Fall through to the error path.
 	}
 
 	// Error path.
+	if tx.c.GetAutocommit() { // There is nothing to rollback.
+		return
+	}
 	err := tx.Rollback()
 	if err != nil {
 		panic(err)
@@ -92,33 +98,28 @@ func (tx Tx) Commit() error {
 	return tx.c.Exec(`COMMIT`)
 }
 
-// Rollback rollsback the transaction.
+// Rollback rolls back the transaction,
+// even if the connection has been interrupted.
 //
 // https://www.sqlite.org/lang_transaction.html
 func (tx Tx) Rollback() error {
-	// ROLLBACK even if the connection has been interrupted.
-	old := tx.c.SetInterrupt(context.Background())
-	defer tx.c.SetInterrupt(old)
-	return tx.c.Exec(`ROLLBACK`)
+	return tx.c.txExecInterrupted(`ROLLBACK`)
 }
 
-// Savepoint creates a named SQLite transaction using SAVEPOINT.
-//
-// On success Savepoint returns a release func that will call either
-// RELEASE or ROLLBACK depending on whether the parameter *error
-// points to a nil or non-nil error.
-//
-// This is meant to be deferred:
-//
-//	func doWork(conn *sqlite3.Conn) (err error) {
-//		defer conn.Savepoint()(&err)
-//
-//		// ... do work in the transaction
-//	}
+// Savepoint is a marker within a transaction
+// that allows for partial rollback.
 //
 // https://www.sqlite.org/lang_savepoint.html
-func (c *Conn) Savepoint() (release func(*error)) {
-	name := "sqlite3.Savepoint" // names can be reused
+type Savepoint struct {
+	c    *Conn
+	name string
+}
+
+// Savepoint establishes a new transaction savepoint.
+//
+// https://www.sqlite.org/lang_savepoint.html
+func (c *Conn) Savepoint() Savepoint {
+	name := "sqlite3.Savepoint"
 	var pc [1]uintptr
 	if n := runtime.Callers(2, pc[:]); n > 0 {
 		frames := runtime.CallersFrames(pc[:n])
@@ -127,52 +128,75 @@ func (c *Conn) Savepoint() (release func(*error)) {
 			name = frame.Function
 		}
 	}
+	// Names can be reused; this makes catching bugs more likely.
+	name += "#" + strconv.Itoa(int(rand.Int31()))
 
-	err := c.Exec(fmt.Sprintf("SAVEPOINT %q;", name))
+	err := c.txExecInterrupted(fmt.Sprintf("SAVEPOINT %q;", name))
 	if err != nil {
-		if errors.Is(err, INTERRUPT) {
-			return func(errp *error) {
-				if *errp == nil {
-					*errp = err
-				}
-			}
-		}
 		panic(err)
 	}
+	return Savepoint{c: c, name: name}
+}
 
-	return func(errp *error) {
-		recovered := recover()
-		if recovered != nil {
-			defer panic(recovered)
-		}
+// Release releases the savepoint rolling back any changes
+// if *error points to a non-nil error.
+//
+// This is meant to be deferred:
+//
+//	func doWork(conn *sqlite3.Conn) (err error) {
+//		savept := conn.Savepoint()
+//		defer savept.Release(&err)
+//
+//		// ... do work in the transaction
+//	}
+func (s Savepoint) Release(errp *error) {
+	recovered := recover()
+	if recovered != nil {
+		defer panic(recovered)
+	}
 
-		if c.GetAutocommit() {
-			// There is nothing to commit/rollback.
+	if (errp == nil || *errp == nil) && recovered == nil {
+		// Success path.
+		if s.c.GetAutocommit() { // There is nothing to commit.
 			return
 		}
-
-		if *errp == nil && recovered == nil {
-			// Success path.
-			// RELEASE the savepoint successfully.
-			*errp = c.Exec(fmt.Sprintf("RELEASE %q;", name))
-			if *errp == nil {
-				return
-			}
-			// Possible interrupt, fall through to the error path.
+		*errp = s.c.Exec(fmt.Sprintf("RELEASE %q;", s.name))
+		if *errp == nil {
+			return
 		}
+		// Fall through to the error path.
+	}
 
-		// Error path.
-		// Always ROLLBACK even if the connection has been interrupted.
-		old := c.SetInterrupt(context.Background())
-		defer c.SetInterrupt(old)
-
-		err := c.Exec(fmt.Sprintf("ROLLBACK TO %q;", name))
-		if err != nil {
-			panic(err)
-		}
-		err = c.Exec(fmt.Sprintf("RELEASE %q;", name))
-		if err != nil {
-			panic(err)
-		}
+	// Error path.
+	if s.c.GetAutocommit() { // There is nothing to rollback.
+		return
+	}
+	// ROLLBACK and RELEASE even if interrupted.
+	err := s.c.txExecInterrupted(fmt.Sprintf(`
+		ROLLBACK TO %[1]q;
+		RELEASE %[1]q;
+	`, s.name))
+	if err != nil {
+		panic(err)
 	}
 }
+
+// Rollback rolls the transaction back to the savepoint,
+// even if the connection has been interrupted.
+// Rollback does not release the savepoint.
+//
+// https://www.sqlite.org/lang_transaction.html
+func (s Savepoint) Rollback() error {
+	// ROLLBACK even if interrupted.
+	return s.c.txExecInterrupted(fmt.Sprintf("ROLLBACK TO %q;", s.name))
+}
+
+func (c *Conn) txExecInterrupted(sql string) error {
+	err := c.Exec(sql)
+	if errors.Is(err, INTERRUPT) {
+		old := c.SetInterrupt(context.Background())
+		defer c.SetInterrupt(old)
+		err = c.Exec(sql)
+	}
+	return err
+}

vfs.go

@@ -9,7 +9,6 @@ import (
 	"os"
 	"path/filepath"
 	"runtime"
-	"syscall"
 	"time"
 
 	"github.com/ncruces/julianday"
@@ -166,66 +165,34 @@ func vfsDelete(ctx context.Context, mod api.Module, pVfs, zPath, syncDir uint32)
 	path := memory{mod}.readString(zPath, _MAX_PATHNAME)
 	err := os.Remove(path)
 	if errors.Is(err, fs.ErrNotExist) {
-		return _OK
+		return uint32(IOERR_DELETE_NOENT)
 	}
 	if err != nil {
 		return uint32(IOERR_DELETE)
 	}
 	if runtime.GOOS != "windows" && syncDir != 0 {
 		f, err := os.Open(filepath.Dir(path))
-		if err == nil {
-			err = f.Sync()
-			f.Close()
-		}
 		if err != nil {
-			return uint32(IOERR_DELETE)
+			return _OK
+		}
+		defer f.Close()
+		err = vfsOS.Sync(f, false, false)
+		if err != nil {
+			return uint32(IOERR_DIR_FSYNC)
 		}
 	}
 	return _OK
 }
 
 func vfsAccess(ctx context.Context, mod api.Module, pVfs, zPath uint32, flags _AccessFlag, pResOut uint32) uint32 {
-	// Consider using [syscall.Access] for [ACCESS_READWRITE]/[ACCESS_READ]
-	// (as the Unix VFS does).
-
 	path := memory{mod}.readString(zPath, _MAX_PATHNAME)
-	fi, err := os.Stat(path)
-
+	ok, rc := vfsOS.Access(path, flags)
 	var res uint32
-	switch {
-	case flags == _ACCESS_EXISTS:
-		switch {
-		case err == nil:
-			res = 1
-		case errors.Is(err, fs.ErrNotExist):
-			res = 0
-		default:
-			return uint32(IOERR_ACCESS)
-		}
-
-	case err == nil:
-		var want fs.FileMode = syscall.S_IRUSR
-		if flags == _ACCESS_READWRITE {
-			want |= syscall.S_IWUSR
-		}
-		if fi.IsDir() {
-			want |= syscall.S_IXUSR
-		}
-		if fi.Mode()&want == want {
-			res = 1
-		} else {
-			res = 0
-		}
-
-	case errors.Is(err, fs.ErrPermission):
-		res = 0
-
-	default:
-		return uint32(IOERR_ACCESS)
+	if ok {
+		res = 1
 	}
-
 	memory{mod}.writeUint32(pResOut, res)
-	return _OK
+	return uint32(rc)
 }
 
 func vfsOpen(ctx context.Context, mod api.Module, pVfs, zName, pFile uint32, flags OpenFlag, pOutFlags uint32) uint32 {
@@ -249,14 +216,14 @@ func vfsOpen(ctx context.Context, mod api.Module, pVfs, zName, pFile uint32, fla
 		file, err = os.CreateTemp("", "*.db")
 	} else {
 		name := memory{mod}.readString(zName, _MAX_PATHNAME)
-		file, err = os.OpenFile(name, oflags, 0600)
+		file, err = vfsOS.OpenFile(name, oflags, 0600)
 	}
 	if err != nil {
 		return uint32(CANTOPEN)
 	}
 
 	if flags&OPEN_DELETEONCLOSE != 0 {
-		vfsOS.DeleteOnClose(file)
+		os.Remove(file.Name())
 	}
 
 	vfsFile.Open(ctx, mod, pFile, file)
@@ -312,9 +279,11 @@ func vfsTruncate(ctx context.Context, mod api.Module, pFile uint32, nByte uint64
 	return _OK
 }
 
-func vfsSync(ctx context.Context, mod api.Module, pFile, flags uint32) uint32 {
+func vfsSync(ctx context.Context, mod api.Module, pFile uint32, flags _SyncFlag) uint32 {
+	dataonly := (flags & _SYNC_DATAONLY) != 0
+	fullsync := (flags & 0x0f) == _SYNC_FULL
 	file := vfsFile.GetOS(ctx, mod, pFile)
-	err := file.Sync()
+	err := vfsOS.Sync(file, fullsync, dataonly)
 	if err != nil {
 		return uint32(IOERR_FSYNC)
 	}
@@ -322,9 +291,6 @@ func vfsSync(ctx context.Context, mod api.Module, pFile, flags uint32) uint32 {
 }
 
 func vfsFileSize(ctx context.Context, mod api.Module, pFile, pSize uint32) uint32 {
-	// This uses [os.File.Seek] because we don't care about the offset for reading/writing.
-	// But consider using [os.File.Stat] instead (as other VFSes do).
-
 	file := vfsFile.GetOS(ctx, mod, pFile)
 	off, err := file.Seek(0, io.SeekEnd)
 	if err != nil {

vfs_test.go

@@ -165,7 +165,7 @@ func Test_vfsDelete(t *testing.T) {
 	}
 
 	rc = vfsDelete(ctx, mem.mod, 0, 4, 1)
-	if rc != _OK {
+	if rc != uint32(IOERR_DELETE_NOENT) {
 		t.Fatal("returned", rc)
 	}
 }

vfs_unix.go

@@ -3,13 +3,46 @@
 package sqlite3
 
 import (
+	"io/fs"
 	"os"
 	"runtime"
-	"syscall"
+
+	"golang.org/x/sys/unix"
 )
 
-func (vfsOSMethods) DeleteOnClose(file *os.File) {
-	_ = os.Remove(file.Name())
+func (vfsOSMethods) OpenFile(name string, flag int, perm fs.FileMode) (*os.File, error) {
+	return os.OpenFile(name, flag, perm)
+}
+
+func (vfsOSMethods) Access(path string, flags _AccessFlag) (bool, xErrorCode) {
+	var access uint32 = unix.F_OK
+	switch flags {
+	case _ACCESS_READWRITE:
+		access = unix.R_OK | unix.W_OK
+	case _ACCESS_READ:
+		access = unix.R_OK
+	}
+
+	err := unix.Access(path, access)
+	if err == nil {
+		return true, _OK
+	}
+	return false, _OK
+}
+
+func (vfsOSMethods) Sync(file *os.File, fullsync, dataonly bool) error {
+	if runtime.GOOS == "darwin" && !fullsync {
+		return unix.Fsync(int(file.Fd()))
+	}
+	if runtime.GOOS == "linux" && dataonly {
+		//lint:ignore SA1019 OK on linux
+		_, _, err := unix.Syscall(unix.SYS_FDATASYNC, file.Fd(), 0, 0)
+		if err != 0 {
+			return err
+		}
+		return nil
+	}
+	return file.Sync()
 }
 
 func (vfsOSMethods) GetExclusiveLock(file *os.File) xErrorCode {
@@ -39,8 +72,8 @@ func (vfsOSMethods) ReleaseLock(file *os.File, _ vfsLockState) xErrorCode {
 }
 
 func (vfsOSMethods) unlock(file *os.File, start, len int64) xErrorCode {
-	err := vfsOS.fcntlSetLock(file, &syscall.Flock_t{
-		Type:  syscall.F_UNLCK,
+	err := vfsOS.fcntlSetLock(file, &unix.Flock_t{
+		Type:  unix.F_UNLCK,
 		Start: start,
 		Len:   len,
 	})
@@ -51,85 +84,85 @@ func (vfsOSMethods) unlock(file *os.File, start, len int64) xErrorCode {
 }
 
 func (vfsOSMethods) readLock(file *os.File, start, len int64) xErrorCode {
-	return vfsOS.lockErrorCode(vfsOS.fcntlSetLock(file, &syscall.Flock_t{
-		Type:  syscall.F_RDLCK,
+	return vfsOS.lockErrorCode(vfsOS.fcntlSetLock(file, &unix.Flock_t{
+		Type:  unix.F_RDLCK,
 		Start: start,
 		Len:   len,
 	}), IOERR_RDLOCK)
 }
 
 func (vfsOSMethods) writeLock(file *os.File, start, len int64) xErrorCode {
-	return vfsOS.lockErrorCode(vfsOS.fcntlSetLock(file, &syscall.Flock_t{
-		Type:  syscall.F_WRLCK,
+	return vfsOS.lockErrorCode(vfsOS.fcntlSetLock(file, &unix.Flock_t{
+		Type:  unix.F_WRLCK,
 		Start: start,
 		Len:   len,
 	}), IOERR_LOCK)
 }
 
 func (vfsOSMethods) checkLock(file *os.File, start, len int64) (bool, xErrorCode) {
-	lock := syscall.Flock_t{
-		Type:  syscall.F_RDLCK,
+	lock := unix.Flock_t{
+		Type:  unix.F_RDLCK,
 		Start: start,
 		Len:   len,
 	}
 	if vfsOS.fcntlGetLock(file, &lock) != nil {
 		return false, IOERR_CHECKRESERVEDLOCK
 	}
-	return lock.Type != syscall.F_UNLCK, _OK
+	return lock.Type != unix.F_UNLCK, _OK
 }
 
-func (vfsOSMethods) fcntlGetLock(file *os.File, lock *syscall.Flock_t) error {
+func (vfsOSMethods) fcntlGetLock(file *os.File, lock *unix.Flock_t) error {
 	var F_OFD_GETLK int
 	switch runtime.GOOS {
 	case "linux":
 		// https://github.com/torvalds/linux/blob/master/include/uapi/asm-generic/fcntl.h
-		F_OFD_GETLK = 36 // F_OFD_GETLK
+		F_OFD_GETLK = 36
 	case "darwin":
 		// https://github.com/apple/darwin-xnu/blob/main/bsd/sys/fcntl.h
-		F_OFD_GETLK = 92 // F_OFD_GETLK
+		F_OFD_GETLK = 92
 	case "illumos":
 		// https://github.com/illumos/illumos-gate/blob/master/usr/src/uts/common/sys/fcntl.h
-		F_OFD_GETLK = 47 // F_OFD_GETLK
+		F_OFD_GETLK = 47
 	default:
 		return notImplErr
 	}
-	return syscall.FcntlFlock(file.Fd(), F_OFD_GETLK, lock)
+	return unix.FcntlFlock(file.Fd(), F_OFD_GETLK, lock)
 }
 
-func (vfsOSMethods) fcntlSetLock(file *os.File, lock *syscall.Flock_t) error {
+func (vfsOSMethods) fcntlSetLock(file *os.File, lock *unix.Flock_t) error {
 	var F_OFD_SETLK int
 	switch runtime.GOOS {
 	case "linux":
 		// https://github.com/torvalds/linux/blob/master/include/uapi/asm-generic/fcntl.h
-		F_OFD_SETLK = 37 // F_OFD_SETLK
+		F_OFD_SETLK = 37
 	case "darwin":
 		// https://github.com/apple/darwin-xnu/blob/main/bsd/sys/fcntl.h
-		F_OFD_SETLK = 90 // F_OFD_SETLK
+		F_OFD_SETLK = 90
 	case "illumos":
 		// https://github.com/illumos/illumos-gate/blob/master/usr/src/uts/common/sys/fcntl.h
-		F_OFD_SETLK = 48 // F_OFD_SETLK
+		F_OFD_SETLK = 48
 	default:
 		return notImplErr
 	}
-	return syscall.FcntlFlock(file.Fd(), F_OFD_SETLK, lock)
+	return unix.FcntlFlock(file.Fd(), F_OFD_SETLK, lock)
 }
 
 func (vfsOSMethods) lockErrorCode(err error, def xErrorCode) xErrorCode {
 	if err == nil {
 		return _OK
 	}
-	if errno, ok := err.(syscall.Errno); ok {
+	if errno, ok := err.(unix.Errno); ok {
 		switch errno {
 		case
-			syscall.EACCES,
-			syscall.EAGAIN,
-			syscall.EBUSY,
-			syscall.EINTR,
-			syscall.ENOLCK,
-			syscall.EDEADLK,
-			syscall.ETIMEDOUT:
+			unix.EACCES,
+			unix.EAGAIN,
+			unix.EBUSY,
+			unix.EINTR,
+			unix.ENOLCK,
+			unix.EDEADLK,
+			unix.ETIMEDOUT:
 			return xErrorCode(BUSY)
-		case syscall.EPERM:
+		case unix.EPERM:
 			return xErrorCode(PERM)
 		}
 	}

vfs_windows.go

@@ -1,13 +1,69 @@
 package sqlite3
 
 import (
+	"errors"
+	"io/fs"
 	"os"
 	"syscall"
 
 	"golang.org/x/sys/windows"
 )
 
-func (vfsOSMethods) DeleteOnClose(file *os.File) {}
+// OpenFile is a simplified copy of [os.openFileNolog]
+// that uses syscall.FILE_SHARE_DELETE.
+// https://go.dev/src/os/file_windows.go
+//
+// See: https://go.dev/issue/32088
+func (vfsOSMethods) OpenFile(name string, flag int, perm fs.FileMode) (*os.File, error) {
+	if name == "" {
+		return nil, &os.PathError{Op: "open", Path: name, Err: syscall.ENOENT}
+	}
+	r, e := syscallOpen(name, flag, uint32(perm.Perm()))
+	if e != nil {
+		return nil, &os.PathError{Op: "open", Path: name, Err: e}
+	}
+	return os.NewFile(uintptr(r), name), nil
+}
+
+func (vfsOSMethods) Sync(file *os.File, fullsync, dataonly bool) error {
+	return file.Sync()
+}
+
+func (vfsOSMethods) Access(path string, flags _AccessFlag) (bool, xErrorCode) {
+	fi, err := os.Stat(path)
+
+	switch {
+	case flags == _ACCESS_EXISTS:
+		switch {
+		case err == nil:
+			return true, _OK
+		case errors.Is(err, fs.ErrNotExist):
+			return false, _OK
+		default:
+			return false, IOERR_ACCESS
+		}
+
+	case err == nil:
+		var want fs.FileMode = syscall.S_IRUSR
+		if flags == _ACCESS_READWRITE {
+			want |= syscall.S_IWUSR
+		}
+		if fi.IsDir() {
+			want |= syscall.S_IXUSR
+		}
+		if fi.Mode()&want == want {
+			return true, _OK
+		} else {
+			return false, _OK
+		}
+
+	case errors.Is(err, fs.ErrPermission):
+		return false, _OK
+
+	default:
+		return false, IOERR_ACCESS
+	}
+}
 
 func (vfsOSMethods) GetExclusiveLock(file *os.File) xErrorCode {
 	// Release the SHARED lock.
@@ -63,6 +119,9 @@ func (vfsOSMethods) ReleaseLock(file *os.File, state vfsLockState) xErrorCode {
 func (vfsOSMethods) unlock(file *os.File, start, len uint32) xErrorCode {
 	err := windows.UnlockFileEx(windows.Handle(file.Fd()),
 		0, len, 0, &windows.Overlapped{Offset: start})
+	if err == windows.ERROR_NOT_LOCKED {
+		return _OK
+	}
 	if err != nil {
 		return IOERR_UNLOCK
 	}
@@ -95,8 +154,66 @@ func (vfsOSMethods) lockErrorCode(err error, def xErrorCode) xErrorCode {
 	if err == nil {
 		return _OK
 	}
-	if errno, _ := err.(syscall.Errno); errno == windows.ERROR_INVALID_HANDLE {
-		return def
+	if errno, ok := err.(syscall.Errno); ok {
+		// https://devblogs.microsoft.com/oldnewthing/20140905-00/?p=63
+		switch errno {
+		case
+			windows.ERROR_LOCK_VIOLATION,
+			windows.ERROR_IO_PENDING:
+			return xErrorCode(BUSY)
+		}
 	}
-	return xErrorCode(BUSY)
+	return def
+}
+
+// syscallOpen is a simplified copy of [syscall.Open]
+// that uses syscall.FILE_SHARE_DELETE.
+// https://go.dev/src/syscall/syscall_windows.go
+func syscallOpen(path string, mode int, perm uint32) (fd syscall.Handle, err error) {
+	if len(path) == 0 {
+		return syscall.InvalidHandle, syscall.ERROR_FILE_NOT_FOUND
+	}
+	pathp, err := syscall.UTF16PtrFromString(path)
+	if err != nil {
+		return syscall.InvalidHandle, err
+	}
+	var access uint32
+	switch mode & (syscall.O_RDONLY | syscall.O_WRONLY | syscall.O_RDWR) {
+	case syscall.O_RDONLY:
+		access = syscall.GENERIC_READ
+	case syscall.O_WRONLY:
+		access = syscall.GENERIC_WRITE
+	case syscall.O_RDWR:
+		access = syscall.GENERIC_READ | syscall.GENERIC_WRITE
+	}
+	if mode&syscall.O_CREAT != 0 {
+		access |= syscall.GENERIC_WRITE
+	}
+	if mode&syscall.O_APPEND != 0 {
+		access &^= syscall.GENERIC_WRITE
+		access |= syscall.FILE_APPEND_DATA
+	}
+	sharemode := uint32(syscall.FILE_SHARE_READ | syscall.FILE_SHARE_WRITE | syscall.FILE_SHARE_DELETE)
+	var createmode uint32
+	switch {
+	case mode&(syscall.O_CREAT|syscall.O_EXCL) == (syscall.O_CREAT | syscall.O_EXCL):
+		createmode = syscall.CREATE_NEW
+	case mode&(syscall.O_CREAT|syscall.O_TRUNC) == (syscall.O_CREAT | syscall.O_TRUNC):
+		createmode = syscall.CREATE_ALWAYS
+	case mode&syscall.O_CREAT == syscall.O_CREAT:
+		createmode = syscall.OPEN_ALWAYS
+	case mode&syscall.O_TRUNC == syscall.O_TRUNC:
+		createmode = syscall.TRUNCATE_EXISTING
+	default:
+		createmode = syscall.OPEN_EXISTING
+	}
+	var attrs uint32 = syscall.FILE_ATTRIBUTE_NORMAL
+	if perm&syscall.S_IWRITE == 0 {
+		attrs = syscall.FILE_ATTRIBUTE_READONLY
+	}
+	if createmode == syscall.OPEN_EXISTING && access == syscall.GENERIC_READ {
+		// Necessary for opening directory handles.
+		attrs |= syscall.FILE_FLAG_BACKUP_SEMANTICS
+	}
+	return syscall.CreateFile(pathp, access, sharemode, nil, createmode, attrs, 0)
 }