SQLite 3.45.0.

Bumps [golang.org/x/crypto](https://github.com/golang/crypto) from 0.17.0 to 0.18.0.
- [Commits](https://github.com/golang/crypto/compare/v0.17.0...v0.18.0)

---
updated-dependencies:
- dependency-name: golang.org/x/crypto
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/bsd.yml

@@ -13,7 +13,7 @@ jobs:
         lfs: 'true'
 
     - name: Test
-      uses: cross-platform-actions/action@v0.21.1
+      uses: cross-platform-actions/action@v0.22.0
       with:
         operating_system: freebsd
         version: '13.2'

.github/workflows/cross.sh

@@ -12,7 +12,7 @@ echo openbsd       ; GOOS=openbsd   GOARCH=amd64 go build .
 echo plan9         ; GOOS=plan9     GOARCH=amd64 go build .
 echo solaris       ; GOOS=solaris   GOARCH=amd64 go build .
 echo windows       ; GOOS=windows   GOARCH=amd64 go build .
-# echo aix         ; GOOS=aix       GOARCH=ppc64 go build .
+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 .

README.md

@@ -36,6 +36,8 @@ Go, wazero and [`x/sys`](https://pkg.go.dev/golang.org/x/sys) are the _only_ run
   reads [comma-separated values](https://sqlite.org/csv.html).
 - [`github.com/ncruces/go-sqlite3/ext/fileio`](https://pkg.go.dev/github.com/ncruces/go-sqlite3/ext/fileio)
   reads, writes and lists files.
+- [`github.com/ncruces/go-sqlite3/ext/hash`](https://pkg.go.dev/github.com/ncruces/go-sqlite3/ext/hash)
+  provides cryptographic hash functions.
 - [`github.com/ncruces/go-sqlite3/ext/lines`](https://pkg.go.dev/github.com/ncruces/go-sqlite3/ext/lines)
   reads data [line-by-line](https://github.com/asg017/sqlite-lines).
 - [`github.com/ncruces/go-sqlite3/ext/pivot`](https://pkg.go.dev/github.com/ncruces/go-sqlite3/ext/pivot)
@@ -53,14 +55,17 @@ Go, wazero and [`x/sys`](https://pkg.go.dev/golang.org/x/sys) are the _only_ run
 
 ### Advanced features
 
-- [x] [incremental BLOB I/O](https://sqlite.org/c3ref/blob_open.html)
-- [x] [nested transactions](https://sqlite.org/lang_savepoint.html)
-- [x] [custom functions](https://sqlite.org/c3ref/create_function.html)
-- [x] [virtual tables](https://sqlite.org/vtab.html)
-- [x] [custom VFSes](https://sqlite.org/vfs.html)
-- [x] [online backup](https://sqlite.org/backup.html)
-- [x] [JSON support](https://sqlite.org/json1.html)
-- [x] [Unicode support](https://sqlite.org/src/dir/ext/icu)
+- [incremental BLOB I/O](https://sqlite.org/c3ref/blob_open.html)
+- [nested transactions](https://sqlite.org/lang_savepoint.html)
+- [custom functions](https://sqlite.org/c3ref/create_function.html)
+- [virtual tables](https://sqlite.org/vtab.html)
+- [custom VFSes](https://sqlite.org/vfs.html)
+- [online backup](https://sqlite.org/backup.html)
+- [JSON support](https://sqlite.org/json1.html)
+- [math functions](https://sqlite.org/lang_mathfunc.html)
+- [full-text search](https://sqlite.org/fts5.html)
+- [geospatial search](https://sqlite.org/geopoly.html)
+- [and more…](embed/README.md)
 
 ### Caveats
 
@@ -105,12 +110,22 @@ 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).
 
-#### Testing
+### Testing
+
+This project aims for [high test coverage](https://github.com/ncruces/go-sqlite3/wiki/Test-coverage-report).
+It also benefits greatly from [SQLite's](https://www.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
 [mptest](https://github.com/sqlite/sqlite/blob/master/mptest/mptest.c)
 on Linux, macOS, Windows and FreeBSD.
-Performance is tested by running
+
+### Performance
+
+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
 [speedtest1](https://github.com/sqlite/sqlite/blob/master/test/speedtest1.c).
 
 ### Alternatives

config.go

@@ -0,0 +1,57 @@
+package sqlite3
+
+import (
+	"context"
+
+	"github.com/ncruces/go-sqlite3/internal/util"
+	"github.com/tetratelabs/wazero/api"
+)
+
+// Config makes configuration changes to a database connection.
+// Only boolean configuration options are supported.
+// Called with no arg reads the current configuration value,
+// called with one arg sets and returns the new value.
+//
+// https://sqlite.org/c3ref/db_config.html
+func (c *Conn) Config(op DBConfig, arg ...bool) (bool, error) {
+	defer c.arena.mark()()
+	argsPtr := c.arena.new(2 * ptrlen)
+
+	var flag int
+	switch {
+	case len(arg) == 0:
+		flag = -1
+	case arg[0]:
+		flag = 1
+	}
+
+	util.WriteUint32(c.mod, argsPtr+0*ptrlen, uint32(flag))
+	util.WriteUint32(c.mod, argsPtr+1*ptrlen, argsPtr)
+
+	r := c.call("sqlite3_db_config", uint64(c.handle),
+		uint64(op), uint64(argsPtr))
+	return util.ReadUint32(c.mod, argsPtr) != 0, c.error(r)
+}
+
+// ConfigLog sets up the error logging callback for the connection.
+//
+// https://www.sqlite.org/errlog.html
+func (c *Conn) ConfigLog(cb func(code ExtendedErrorCode, msg string)) error {
+	var enable uint64
+	if cb != nil {
+		enable = 1
+	}
+	r := c.call("sqlite3_config_log_go", enable)
+	if err := c.error(r); err != nil {
+		return err
+	}
+	c.log = cb
+	return nil
+}
+
+func logCallback(ctx context.Context, mod api.Module, _, iCode, zMsg uint32) {
+	if c, ok := ctx.Value(connKey{}).(*Conn); ok && c.log != nil {
+		msg := util.ReadString(mod, zMsg, _MAX_LENGTH)
+		c.log(xErrorCode(iCode), msg)
+	}
+}

conn.go

@@ -20,6 +20,7 @@ type Conn struct {
 
 	interrupt context.Context
 	pending   *Stmt
+	log       func(code xErrorCode, msg string)
 	arena     arena
 
 	handle uint32
@@ -243,21 +244,27 @@ func (c *Conn) SetInterrupt(ctx context.Context) (old context.Context) {
 	// A busy SQL statement prevents SQLite from ignoring an interrupt
 	// that comes before any other statements are started.
 	if c.pending == nil {
-		c.pending, _, _ = c.Prepare(`SELECT 1 UNION ALL SELECT 2`)
-	} else {
-		c.pending.Reset()
+		c.pending, _, _ = c.Prepare(`WITH RECURSIVE c(x) AS (VALUES(0) UNION ALL SELECT x FROM c) SELECT x FROM c`)
 	}
 
 	old = c.interrupt
 	c.interrupt = ctx
-	if ctx == nil || ctx.Done() == nil {
-		return old
-	}
 
-	c.pending.Step()
+	if old != nil && old.Done() != nil && (ctx == nil || ctx.Err() == nil) {
+		c.pending.Reset()
+	}
+	if ctx != nil && ctx.Done() != nil {
+		c.pending.Step()
+	}
 	return old
 }
 
+func (c *Conn) checkInterrupt() {
+	if c.interrupt != nil && c.interrupt.Err() != nil {
+		c.call("sqlite3_interrupt", uint64(c.handle))
+	}
+}
+
 func progressCallback(ctx context.Context, mod api.Module, _ uint32) uint32 {
 	if c, ok := ctx.Value(connKey{}).(*Conn); ok {
 		if c.interrupt != nil && c.interrupt.Err() != nil {
@@ -267,12 +274,6 @@ func progressCallback(ctx context.Context, mod api.Module, _ uint32) uint32 {
 	return 0
 }
 
-func (c *Conn) checkInterrupt() {
-	if c.interrupt != nil && c.interrupt.Err() != nil {
-		c.call("sqlite3_interrupt", uint64(c.handle))
-	}
-}
-
 // Pragma executes a PRAGMA statement and returns any results.
 //
 // https://sqlite.org/pragma.html

const.go

@@ -9,10 +9,11 @@ const (
 
 	_UTF8 = 1
 
-	_MAX_NAME            = 512 // Used for short strings: names, error messages…
+	_MAX_NAME            = 1e6 // Self-imposed limit for most NUL terminated strings.
 	_MAX_LENGTH          = 1e9
 	_MAX_SQL_LENGTH      = 1e9
 	_MAX_ALLOCATION_SIZE = 0x7ffffeff
+	_MAX_FUNCTION_ARG    = 100
 
 	ptrlen = 4
 )
@@ -200,6 +201,34 @@ const (
 	STMTSTATUS_MEMUSED       StmtStatus = 99
 )
 
+// DBConfig are the available database connection configuration options.
+//
+// https://sqlite.org/c3ref/c_dbconfig_defensive.html
+type DBConfig uint32
+
+const (
+	// DBCONFIG_MAINDBNAME         DBConfig = 1000
+	// DBCONFIG_LOOKASIDE          DBConfig = 1001
+	DBCONFIG_ENABLE_FKEY           DBConfig = 1002
+	DBCONFIG_ENABLE_TRIGGER        DBConfig = 1003
+	DBCONFIG_ENABLE_FTS3_TOKENIZER DBConfig = 1004
+	DBCONFIG_ENABLE_LOAD_EXTENSION DBConfig = 1005
+	DBCONFIG_NO_CKPT_ON_CLOSE      DBConfig = 1006
+	DBCONFIG_ENABLE_QPSG           DBConfig = 1007
+	DBCONFIG_TRIGGER_EQP           DBConfig = 1008
+	DBCONFIG_RESET_DATABASE        DBConfig = 1009
+	DBCONFIG_DEFENSIVE             DBConfig = 1010
+	DBCONFIG_WRITABLE_SCHEMA       DBConfig = 1011
+	DBCONFIG_LEGACY_ALTER_TABLE    DBConfig = 1012
+	DBCONFIG_DQS_DML               DBConfig = 1013
+	DBCONFIG_DQS_DDL               DBConfig = 1014
+	DBCONFIG_ENABLE_VIEW           DBConfig = 1015
+	DBCONFIG_LEGACY_FILE_FORMAT    DBConfig = 1016
+	DBCONFIG_TRUSTED_SCHEMA        DBConfig = 1017
+	DBCONFIG_STMT_SCANSTATUS       DBConfig = 1018
+	DBCONFIG_REVERSE_SCANORDER     DBConfig = 1019
+)
+
 // Datatype is a fundamental datatype of SQLite.
 //
 // https://sqlite.org/c3ref/c_blob.html

context.go

@@ -184,7 +184,7 @@ func (ctx Context) ResultJSON(value any) {
 //
 // https://sqlite.org/c3ref/result_blob.html
 func (ctx Context) ResultValue(value Value) {
-	if value.sqlite != ctx.c.sqlite {
+	if value.c != ctx.c {
 		ctx.ResultError(MISUSE)
 		return
 	}
@@ -218,3 +218,12 @@ func (ctx Context) ResultError(err error) {
 			uint64(ctx.handle), uint64(code))
 	}
 }
+
+// VTabNoChange may return true if a column is being fetched as part
+// of an update during which the column value will not change.
+//
+// https://www.sqlite.org/c3ref/vtab_nochange.html
+func (ctx Context) VTabNoChange() bool {
+	r := ctx.c.call("sqlite3_vtab_nochange", uint64(ctx.handle))
+	return r != 0
+}

driver/driver.go

@@ -50,6 +50,7 @@ import (
 	"net/url"
 	"strings"
 	"time"
+	"unsafe"
 
 	"github.com/ncruces/go-sqlite3"
 	"github.com/ncruces/go-sqlite3/internal/util"
@@ -417,10 +418,10 @@ func (s *stmt) setupBindings(args []driver.NamedValue) error {
 				err = s.Stmt.BindZeroBlob(id, int64(a))
 			case time.Time:
 				err = s.Stmt.BindTime(id, a, s.tmWrite)
-			case interface{ Pointer() any }:
-				err = s.Stmt.BindPointer(id, a.Pointer())
-			case interface{ JSON() any }:
-				err = s.Stmt.BindJSON(id, a.JSON())
+			case util.JSON:
+				err = s.Stmt.BindJSON(id, a.Value)
+			case util.PointerUnwrap:
+				err = s.Stmt.BindPointer(id, util.UnwrapPointer(a))
 			case nil:
 				err = s.Stmt.BindNull(id)
 			default:
@@ -437,9 +438,8 @@ func (s *stmt) setupBindings(args []driver.NamedValue) error {
 func (s *stmt) CheckNamedValue(arg *driver.NamedValue) error {
 	switch arg.Value.(type) {
 	case bool, int, int64, float64, string, []byte,
-		sqlite3.ZeroBlob, time.Time,
-		interface{ Pointer() any },
-		interface{ JSON() any },
+		time.Time, sqlite3.ZeroBlob,
+		util.JSON, util.PointerUnwrap,
 		nil:
 		return nil
 	default:
@@ -533,46 +533,34 @@ func (r *rows) Next(dest []driver.Value) error {
 		return io.EOF
 	}
 
+	data := unsafe.Slice((*any)(unsafe.SliceData(dest)), len(dest))
+	err := r.Stmt.Columns(data)
 	for i := range dest {
-		t := r.Stmt.ColumnType(i)
-		if tm, ok := r.decodeTime(i, t); ok {
-			dest[i] = tm
-			continue
-		}
-		switch t {
-		case sqlite3.INTEGER:
-			dest[i] = r.Stmt.ColumnInt64(i)
-		case sqlite3.FLOAT:
-			dest[i] = r.Stmt.ColumnFloat(i)
-		case sqlite3.BLOB:
-			dest[i] = r.Stmt.ColumnRawBlob(i)
-		case sqlite3.TEXT:
-			dest[i] = stringOrTime(r.Stmt.ColumnText(i))
-		case sqlite3.NULL:
-			dest[i] = nil
-		default:
-			panic(util.AssertErr())
+		if t, ok := r.decodeTime(i, dest[i]); ok {
+			dest[i] = t
+		} else if s, ok := dest[i].(string); ok {
+			dest[i] = stringOrTime(s)
 		}
 	}
-
-	return r.Stmt.Err()
+	return err
 }
 
-func (r *rows) decodeTime(i int, typ sqlite3.Datatype) (_ time.Time, _ bool) {
+func (r *rows) decodeTime(i int, v any) (_ time.Time, _ bool) {
 	if r.tmRead == sqlite3.TimeFormatDefault {
 		return
 	}
-	switch typ {
-	case sqlite3.INTEGER, sqlite3.FLOAT, sqlite3.TEXT:
-		// maybe
-	default:
-		return
-	}
 	switch r.declType(i) {
 	case "DATE", "TIME", "DATETIME", "TIMESTAMP":
 		// maybe
 	default:
 		return
 	}
-	return r.Stmt.ColumnTime(i, r.tmRead), r.Stmt.Err() == nil
+	switch v.(type) {
+	case int64, float64, string:
+		// maybe
+	default:
+		return
+	}
+	t, err := r.tmRead.Decode(v)
+	return t, err == nil
 }

driver/time.go

@@ -23,8 +23,9 @@ func stringOrTime(text string) driver.Value {
 	}
 
 	// Slow path.
+	var buf [len(time.RFC3339Nano)]byte
 	date, err := time.Parse(time.RFC3339Nano, text)
-	if err == nil && date.Format(time.RFC3339Nano) == text {
+	if err == nil && text == string(date.AppendFormat(buf[:0], time.RFC3339Nano)) {
 		return date
 	}
 	return text

driver/time_test.go

@@ -67,7 +67,7 @@ func Fuzz_stringOrTime_2(f *testing.F) {
 			if !v.Equal(date) {
 				t.Fatalf("did not round-trip: %v", date)
 			}
-			// Make with the same zone offset:
+			// With the same zone offset:
 			_, off1 := v.Zone()
 			_, off2 := date.Zone()
 			if off1 != off2 {

embed/README.md

@@ -1,6 +1,6 @@
 # Embeddable WASM build of SQLite
 
-This folder includes an embeddable WASM build of SQLite 3.44.2 for use with
+This folder includes an embeddable WASM build of SQLite 3.45.0 for use with
 [`github.com/ncruces/go-sqlite3`](https://pkg.go.dev/github.com/ncruces/go-sqlite3).
 
 The following optional features are compiled in:
@@ -12,6 +12,7 @@ The following optional features are compiled in:
 - [soundex](https://sqlite.org/lang_corefunc.html#soundex)
 - [base64](https://github.com/sqlite/sqlite/blob/master/ext/misc/base64.c)
 - [decimal](https://github.com/sqlite/sqlite/blob/master/ext/misc/decimal.c)
+- [ieee754](https://github.com/sqlite/sqlite/blob/master/ext/misc/ieee754.c)
 - [regexp](https://github.com/sqlite/sqlite/blob/master/ext/misc/regexp.c)
 - [series](https://github.com/sqlite/sqlite/blob/master/ext/misc/series.c)
 - [uint](https://github.com/sqlite/sqlite/blob/master/ext/misc/uint.c)

embed/build.sh

@@ -7,7 +7,8 @@ ROOT=../
 BINARYEN="$ROOT/tools/binaryen-version_116/bin"
 WASI_SDK="$ROOT/tools/wasi-sdk-21.0/bin"
 
-"$WASI_SDK/clang" --target=wasm32-wasi -flto -g0 -O2 \
+"$WASI_SDK/clang" --target=wasm32-wasi -std=c17 -flto -g0 -O2 \
+  -Wall -Wextra -Wno-unused-parameter \
 	-o sqlite3.wasm "$ROOT/sqlite3/main.c" \
 	-I"$ROOT/sqlite3" \
 	-mexec-model=reactor \

embed/exports.txt

@@ -39,11 +39,14 @@ sqlite3_column_name
 sqlite3_column_text
 sqlite3_column_type
 sqlite3_column_value
+sqlite3_columns_go
+sqlite3_config_log_go
 sqlite3_create_aggregate_function_go
 sqlite3_create_collation_go
 sqlite3_create_function_go
 sqlite3_create_module_go
 sqlite3_create_window_function_go
+sqlite3_db_config
 sqlite3_declare_vtab
 sqlite3_errcode
 sqlite3_errmsg
@@ -87,6 +90,7 @@ sqlite3_value_dup
 sqlite3_value_free
 sqlite3_value_int64
 sqlite3_value_nochange
+sqlite3_value_numeric_type
 sqlite3_value_pointer_go
 sqlite3_value_text
 sqlite3_value_type

error.go

@@ -138,14 +138,14 @@ func (e ExtendedErrorCode) Timeout() bool {
 
 func errorCode(err error, def ErrorCode) (msg string, code uint32) {
 	switch code := err.(type) {
+	case nil:
+		return "", _OK
 	case ErrorCode:
 		return "", uint32(code)
-	case ExtendedErrorCode:
+	case xErrorCode:
 		return "", uint32(code)
 	case *Error:
 		return code.msg, uint32(code.code)
-	case nil:
-		return "", _OK
 	}
 
 	var ecode ErrorCode

ext/array/array.go

@@ -8,15 +8,17 @@ import (
 	"reflect"
 
 	"github.com/ncruces/go-sqlite3"
+	"github.com/ncruces/go-sqlite3/internal/util"
 )
 
 // Register registers the array single-argument, table-valued SQL function.
-// The argument must be an [sqlite3.Pointer] to a Go slice or array
-// of ints, floats, bools, strings or blobs.
+// The argument must be bound to a Go slice or array of
+// ints, floats, bools, strings or byte slices,
+// using [sqlite3.BindPointer] or [sqlite3.Pointer].
 func Register(db *sqlite3.Conn) {
 	sqlite3.CreateModule[array](db, "array", nil,
 		func(db *sqlite3.Conn, _, _, _ string, _ ...string) (array, error) {
-			err := db.DeclareVtab(`CREATE TABLE x(value, array HIDDEN)`)
+			err := db.DeclareVTab(`CREATE TABLE x(value, array HIDDEN)`)
 			return array{}, err
 		})
 }
@@ -102,7 +104,7 @@ func (c *cursor) Column(ctx *sqlite3.Context, n int) error {
 		ctx.ResultBlob(v.Bytes())
 
 	default:
-		return fmt.Errorf("array: unsupported element:%.0w %v", sqlite3.MISMATCH, v.Type())
+		return fmt.Errorf("array: unsupported element:%.0w %v", sqlite3.MISMATCH, util.ReflectType(v))
 	}
 	return nil
 }
@@ -120,16 +122,15 @@ func (c *cursor) Filter(idxNum int, idxStr string, arg ...sqlite3.Value) error {
 }
 
 func indexable(v reflect.Value) (reflect.Value, error) {
-	if v.Kind() == reflect.Slice {
+	switch v.Kind() {
+	case reflect.Slice:
 		return v, nil
-	}
-	if v.Kind() == reflect.Array {
+	case reflect.Array:
 		return v, nil
-	}
-	if v.Kind() == reflect.Pointer {
+	case reflect.Pointer:
 		if v := v.Elem(); v.Kind() == reflect.Array {
 			return v, nil
 		}
 	}
-	return v, fmt.Errorf("array: unsupported argument:%.0w %v", sqlite3.MISMATCH, v)
+	return v, fmt.Errorf("array: unsupported argument:%.0w %v", sqlite3.MISMATCH, util.ReflectType(v))
 }

ext/array/array_test.go

@@ -13,7 +13,7 @@ import (
 	"github.com/ncruces/go-sqlite3/ext/array"
 )
 
-func Example() {
+func Example_driver() {
 	db, err := driver.Open(":memory:", func(c *sqlite3.Conn) error {
 		array.Register(c)
 		return nil
@@ -51,6 +51,42 @@ func Example() {
 	// geopoly_within
 }
 
+func Example() {
+	db, err := sqlite3.Open(":memory:")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer db.Close()
+
+	array.Register(db)
+
+	stmt, _, err := db.Prepare(`
+		SELECT name
+		FROM pragma_function_list
+		WHERE name like 'geopoly%' AND narg IN array(?)`)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer stmt.Close()
+
+	err = stmt.BindPointer(1, [...]int{2, 3, 4})
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	for stmt.Step() {
+		fmt.Printf("%s\n", stmt.ColumnText(0))
+	}
+	if err := stmt.Err(); err != nil {
+		log.Fatal(err)
+	}
+	// Unordered output:
+	// geopoly_regular
+	// geopoly_overlap
+	// geopoly_contains_point
+	// geopoly_within
+}
+
 func Test_cursor_Column(t *testing.T) {
 	t.Parallel()
 

ext/blobio/blob.go

@@ -23,7 +23,8 @@ import (
 //
 // Opens blobs for reading or writing.
 // The callback is invoked for each open blob,
-// and must be an [sqlite3.Pointer] to an [OpenCallback].
+// and must be bound to an [OpenCallback],
+// using [sqlite3.BindPointer] or [sqlite3.Pointer].
 // The optional args will be passed to the callback,
 // along with the [sqlite3.Blob] handle.
 //

ext/csv/arg.go

@@ -0,0 +1,36 @@
+package csv
+
+import (
+	"fmt"
+	"strconv"
+
+	"github.com/ncruces/go-sqlite3/internal/util"
+	"github.com/ncruces/go-sqlite3/util/vtabutil"
+)
+
+func uintArg(key, val string) (int, error) {
+	i, err := strconv.ParseUint(val, 10, 15)
+	if err != nil {
+		return 0, fmt.Errorf("csv: invalid %q parameter: %s", key, val)
+	}
+	return int(i), nil
+}
+
+func boolArg(key, val string) (bool, error) {
+	if val == "" {
+		return true, nil
+	}
+	b, ok := util.ParseBool(val)
+	if ok {
+		return b, nil
+	}
+	return false, fmt.Errorf("csv: invalid %q parameter: %s", key, val)
+}
+
+func runeArg(key, val string) (rune, error) {
+	r, _, tail, err := strconv.UnquoteChar(vtabutil.Unquote(val), 0)
+	if tail != "" || err != nil {
+		return 0, fmt.Errorf("csv: invalid %q parameter: %s", key, val)
+	}
+	return r, nil
+}

ext/csv/arg_test.go

@@ -1,8 +1,12 @@
 package csv
 
-import "testing"
+import (
+	"testing"
 
-func Test_uintParam(t *testing.T) {
+	"github.com/ncruces/go-sqlite3/util/vtabutil"
+)
+
+func Test_uintArg(t *testing.T) {
 	t.Parallel()
 
 	tests := []struct {
@@ -20,22 +24,22 @@ func Test_uintParam(t *testing.T) {
 	}
 	for _, tt := range tests {
 		t.Run(tt.arg, func(t *testing.T) {
-			key, val := getParam(tt.arg)
+			key, val := vtabutil.NamedArg(tt.arg)
 			if key != tt.key {
-				t.Errorf("getParam() %v, want err %v", key, tt.key)
+				t.Errorf("NamedArg() %v, want err %v", key, tt.key)
 			}
-			got, err := uintParam(key, val)
+			got, err := uintArg(key, val)
 			if (err != nil) != tt.err {
-				t.Fatalf("uintParam() error = %v, want err %v", err, tt.err)
+				t.Fatalf("uintArg() error = %v, want err %v", err, tt.err)
 			}
 			if got != tt.val {
-				t.Errorf("uintParam() = %v, want %v", got, tt.val)
+				t.Errorf("uintArg() = %v, want %v", got, tt.val)
 			}
 		})
 	}
 }
 
-func Test_boolParam(t *testing.T) {
+func Test_boolArg(t *testing.T) {
 	tests := []struct {
 		arg string
 		key string
@@ -56,22 +60,22 @@ func Test_boolParam(t *testing.T) {
 	}
 	for _, tt := range tests {
 		t.Run(tt.arg, func(t *testing.T) {
-			key, val := getParam(tt.arg)
+			key, val := vtabutil.NamedArg(tt.arg)
 			if key != tt.key {
-				t.Errorf("getParam() %v, want err %v", key, tt.key)
+				t.Errorf("NamedArg() %v, want err %v", key, tt.key)
 			}
-			got, err := boolParam(key, val)
+			got, err := boolArg(key, val)
 			if (err != nil) != tt.err {
-				t.Fatalf("boolParam() error = %v, want err %v", err, tt.err)
+				t.Fatalf("boolArg() error = %v, want err %v", err, tt.err)
 			}
 			if got != tt.val {
-				t.Errorf("boolParam() = %v, want %v", got, tt.val)
+				t.Errorf("boolArg() = %v, want %v", got, tt.val)
 			}
 		})
 	}
 }
 
-func Test_runeParam(t *testing.T) {
+func Test_runeArg(t *testing.T) {
 	tests := []struct {
 		arg string
 		key string
@@ -88,16 +92,16 @@ func Test_runeParam(t *testing.T) {
 	}
 	for _, tt := range tests {
 		t.Run(tt.arg, func(t *testing.T) {
-			key, val := getParam(tt.arg)
+			key, val := vtabutil.NamedArg(tt.arg)
 			if key != tt.key {
-				t.Errorf("getParam() %v, want err %v", key, tt.key)
+				t.Errorf("NamedArg() %v, want err %v", key, tt.key)
 			}
-			got, err := runeParam(key, val)
+			got, err := runeArg(key, val)
 			if (err != nil) != tt.err {
-				t.Fatalf("runeParam() error = %v, want err %v", err, tt.err)
+				t.Fatalf("runeArg() error = %v, want err %v", err, tt.err)
 			}
 			if got != tt.val {
-				t.Errorf("runeParam() = %v, want %v", got, tt.val)
+				t.Errorf("runeArg() = %v, want %v", got, tt.val)
 			}
 		})
 	}

ext/csv/csv.go

@@ -12,21 +12,22 @@ import (
 	"fmt"
 	"io"
 	"io/fs"
-	"os"
 	"strings"
 
 	"github.com/ncruces/go-sqlite3"
+	"github.com/ncruces/go-sqlite3/util/osutil"
+	"github.com/ncruces/go-sqlite3/util/vtabutil"
 )
 
 // Register registers the CSV virtual table.
-// If a filename is specified, `os.Open` is used to open the file.
+// If a filename is specified, [os.Open] is used to open the file.
 func Register(db *sqlite3.Conn) {
-	RegisterOpen(db, osfs{})
+	RegisterFS(db, osutil.FS{})
 }
 
-// RegisterOpen registers the CSV virtual table.
+// RegisterFS registers the CSV virtual table.
 // If a filename is specified, fsys is used to open the file.
-func RegisterOpen(db *sqlite3.Conn, fsys fs.FS) {
+func RegisterFS(db *sqlite3.Conn, fsys fs.FS) {
 	declare := func(db *sqlite3.Conn, _, _, _ string, arg ...string) (_ *table, err error) {
 		var (
 			filename string
@@ -40,23 +41,23 @@ func RegisterOpen(db *sqlite3.Conn, fsys fs.FS) {
 		)
 
 		for _, arg := range arg {
-			key, val := getParam(arg)
+			key, val := vtabutil.NamedArg(arg)
 			if _, ok := done[key]; ok {
 				return nil, fmt.Errorf("csv: more than one %q parameter", key)
 			}
 			switch key {
 			case "filename":
-				filename = unquoteParam(val)
+				filename = vtabutil.Unquote(val)
 			case "data":
-				data = unquoteParam(val)
+				data = vtabutil.Unquote(val)
 			case "schema":
-				schema = unquoteParam(val)
+				schema = vtabutil.Unquote(val)
 			case "header":
-				header, err = boolParam(key, val)
+				header, err = boolArg(key, val)
 			case "columns":
-				columns, err = uintParam(key, val)
+				columns, err = uintArg(key, val)
 			case "comma":
-				comma, err = runeParam(key, val)
+				comma, err = runeArg(key, val)
 			default:
 				return nil, fmt.Errorf("csv: unknown %q parameter", key)
 			}
@@ -81,8 +82,8 @@ func RegisterOpen(db *sqlite3.Conn, fsys fs.FS) {
 		if schema == "" {
 			var row []string
 			if header || columns < 0 {
-				csv, close, err := table.newReader()
-				defer close.Close()
+				csv, c, err := table.newReader()
+				defer c.Close()
 				if err != nil {
 					return nil, err
 				}
@@ -94,11 +95,11 @@ func RegisterOpen(db *sqlite3.Conn, fsys fs.FS) {
 			schema = getSchema(header, columns, row)
 		}
 
-		err = db.DeclareVtab(schema)
+		err = db.DeclareVTab(schema)
 		if err != nil {
 			return nil, err
 		}
-		err = db.VtabConfig(sqlite3.VTAB_DIRECTONLY)
+		err = db.VTabConfig(sqlite3.VTAB_DIRECTONLY)
 		if err != nil {
 			return nil, err
 		}
@@ -108,12 +109,6 @@ func RegisterOpen(db *sqlite3.Conn, fsys fs.FS) {
 	sqlite3.CreateModule(db, "csv", declare, declare)
 }
 
-type osfs struct{}
-
-func (osfs) Open(name string) (fs.File, error) {
-	return os.Open(name)
-}
-
 type table struct {
 	fsys   fs.FS
 	name   string
@@ -139,13 +134,11 @@ func (t *table) Integrity(schema, table string, flags int) error {
 	if flags&1 != 0 {
 		return nil
 	}
-	csv, close, err := t.newReader()
+	csv, c, err := t.newReader()
 	if err != nil {
 		return err
 	}
-	if close != nil {
-		defer close.Close()
-	}
+	defer c.Close()
 	_, err = csv.ReadAll()
 	return err
 }
@@ -182,20 +175,28 @@ func (t *table) newReader() (*csv.Reader, io.Closer, error) {
 }
 
 type cursor struct {
-	table *table
-	close io.Closer
-	csv   *csv.Reader
-	row   []string
-	rowID int64
+	table  *table
+	closer io.Closer
+	csv    *csv.Reader
+	row    []string
+	rowID  int64
 }
 
-func (c *cursor) Close() error {
-	return c.close.Close()
+func (c *cursor) Close() (err error) {
+	if c.closer != nil {
+		err = c.closer.Close()
+		c.closer = nil
+	}
+	return err
 }
 
 func (c *cursor) Filter(idxNum int, idxStr string, arg ...sqlite3.Value) error {
-	var err error
-	c.csv, c.close, err = c.table.newReader()
+	err := c.Close()
+	if err != nil {
+		return err
+	}
+
+	c.csv, c.closer, err = c.table.newReader()
 	if err != nil {
 		return err
 	}

ext/csv/params.go

@@ -1,65 +0,0 @@
-package csv
-
-import (
-	"fmt"
-	"strconv"
-	"strings"
-)
-
-func getParam(arg string) (key, val string) {
-	key, val, _ = strings.Cut(arg, "=")
-	key = strings.TrimSpace(key)
-	val = strings.TrimSpace(val)
-	return
-}
-
-func uintParam(key, val string) (int, error) {
-	i, err := strconv.ParseUint(val, 10, 15)
-	if err != nil {
-		return 0, fmt.Errorf("csv: invalid %q parameter: %s", key, val)
-	}
-	return int(i), nil
-}
-
-func boolParam(key, val string) (bool, error) {
-	if val == "" || val == "1" ||
-		strings.EqualFold(val, "true") ||
-		strings.EqualFold(val, "yes") ||
-		strings.EqualFold(val, "on") {
-		return true, nil
-	}
-	if val == "0" ||
-		strings.EqualFold(val, "false") ||
-		strings.EqualFold(val, "no") ||
-		strings.EqualFold(val, "off") {
-		return false, nil
-	}
-	return false, fmt.Errorf("csv: invalid %q parameter: %s", key, val)
-}
-
-func runeParam(key, val string) (rune, error) {
-	r, _, tail, err := strconv.UnquoteChar(unquoteParam(val), 0)
-	if tail != "" || err != nil {
-		return 0, fmt.Errorf("csv: invalid %q parameter: %s", key, val)
-	}
-	return r, nil
-}
-
-func unquoteParam(val string) string {
-	if len(val) < 2 {
-		return val
-	}
-	if val[0] != val[len(val)-1] {
-		return val
-	}
-	var old, new string
-	switch val[0] {
-	default:
-		return val
-	case '"':
-		old, new = `""`, `"`
-	case '\'':
-		old, new = `''`, `'`
-	}
-	return strings.ReplaceAll(val[1:len(val)-1], old, new)
-}

ext/fileio/fileio.go

@@ -13,13 +13,13 @@ import (
 )
 
 // Register registers SQL functions readfile, writefile, lsmode,
-// and the eponymous virtual table fsdir.
+// and the table-valued function fsdir.
 func Register(db *sqlite3.Conn) {
 	RegisterFS(db, nil)
 }
 
 // Register registers SQL functions readfile, lsmode,
-// and the eponymous virtual table fsdir;
+// 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)
@@ -27,9 +27,9 @@ func RegisterFS(db *sqlite3.Conn, fsys fs.FS) {
 	if fsys == nil {
 		db.CreateFunction("writefile", -1, sqlite3.DIRECTONLY, writefile)
 	}
-	sqlite3.CreateModule(db, "fsdir", nil, func(db *sqlite3.Conn, module, schema, table string, arg ...string) (fsdir, error) {
-		err := db.DeclareVtab(`CREATE TABLE x(name,mode,mtime,data,path HIDDEN,dir HIDDEN)`)
-		db.VtabConfig(sqlite3.VTAB_DIRECTONLY)
+	sqlite3.CreateModule(db, "fsdir", nil, func(db *sqlite3.Conn, _, _, _ string, _ ...string) (fsdir, error) {
+		err := db.DeclareVTab(`CREATE TABLE x(name,mode,mtime TIMESTAMP,data,path HIDDEN,dir HIDDEN)`)
+		db.VTabConfig(sqlite3.VTAB_DIRECTONLY)
 		return fsdir{fsys}, err
 	})
 }

ext/fileio/fsdir.go

@@ -48,23 +48,23 @@ func (d fsdir) BestIndex(idx *sqlite3.IndexInfo) error {
 }
 
 func (d fsdir) Open() (sqlite3.VTabCursor, error) {
-	return &cursor{fsys: d.fsys}, nil
+	return &cursor{fsdir: d}, nil
 }
 
 type cursor struct {
-	fsys  fs.FS
-	base  string
-	rowID int64
-	eof   bool
+	fsdir
 	curr  entry
 	next  chan entry
 	done  chan struct{}
+	base  string
+	rowID int64
+	eof   bool
 }
 
 type entry struct {
-	path string
 	fs.DirEntry
-	err error
+	err  error
+	path string
 }
 
 func (c *cursor) Close() error {
@@ -180,7 +180,7 @@ func (c *cursor) WalkDirFunc(path string, d fs.DirEntry, err error) error {
 	select {
 	case <-c.done:
 		return fs.SkipAll
-	case c.next <- entry{path, d, err}:
+	case c.next <- entry{d, err, path}:
 		return nil
 	}
 }

ext/fileio/write.go

@@ -10,6 +10,7 @@ import (
 
 	"github.com/ncruces/go-sqlite3"
 	"github.com/ncruces/go-sqlite3/internal/util"
+	"github.com/ncruces/go-sqlite3/util/fsutil"
 )
 
 func writefile(ctx sqlite3.Context, arg ...sqlite3.Value) {
@@ -22,7 +23,7 @@ func writefile(ctx sqlite3.Context, arg ...sqlite3.Value) {
 
 	var mode fs.FileMode
 	if len(arg) > 2 {
-		mode = fixMode(fs.FileMode(arg[2].Int()))
+		mode = fsutil.FileModeFromValue(arg[2])
 	}
 
 	n, err := createFileAndDir(file, mode, arg[1])
@@ -88,40 +89,6 @@ func createFile(path string, mode fs.FileMode, data sqlite3.Value) (int, error)
 	return 0, fmt.Errorf("invalid mode: %v", mode)
 }
 
-func fixMode(mode fs.FileMode) fs.FileMode {
-	const (
-		S_IFMT   fs.FileMode = 0170000
-		S_IFIFO  fs.FileMode = 0010000
-		S_IFCHR  fs.FileMode = 0020000
-		S_IFDIR  fs.FileMode = 0040000
-		S_IFBLK  fs.FileMode = 0060000
-		S_IFREG  fs.FileMode = 0100000
-		S_IFLNK  fs.FileMode = 0120000
-		S_IFSOCK fs.FileMode = 0140000
-	)
-
-	switch mode & S_IFMT {
-	case S_IFDIR:
-		mode |= fs.ModeDir
-	case S_IFLNK:
-		mode |= fs.ModeSymlink
-	case S_IFBLK:
-		mode |= fs.ModeDevice
-	case S_IFCHR:
-		mode |= fs.ModeCharDevice | fs.ModeDevice
-	case S_IFIFO:
-		mode |= fs.ModeNamedPipe
-	case S_IFSOCK:
-		mode |= fs.ModeSocket
-	case S_IFREG, 0:
-		//
-	default:
-		mode |= fs.ModeIrregular
-	}
-
-	return mode &^ S_IFMT
-}
-
 func fixPerm(mode fs.FileMode, def fs.FileMode) fs.FileMode {
 	if mode.Perm() == 0 {
 		return def

ext/fileio/write_test.go

@@ -56,7 +56,7 @@ func Test_writefile(t *testing.T) {
 		var mode fs.FileMode
 		var mtime time.Time
 		var data sql.NullString
-		err := rows.Scan(&name, &mode, sqlite3.TimeFormatUnixFrac.Scanner(&mtime), &data)
+		err := rows.Scan(&name, &mode, &mtime, &data)
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -90,26 +90,3 @@ func Test_writefile(t *testing.T) {
 		t.Log(err)
 	}
 }
-
-func Test_fixMode(t *testing.T) {
-	tests := []struct {
-		mode fs.FileMode
-		want fs.FileMode
-	}{
-		{0010754, 0754 | fs.ModeNamedPipe},
-		{0020754, 0754 | fs.ModeCharDevice | fs.ModeDevice},
-		{0040754, 0754 | fs.ModeDir},
-		{0060754, 0754 | fs.ModeDevice},
-		{0100754, 0754},
-		{0120754, 0754 | fs.ModeSymlink},
-		{0140754, 0754 | fs.ModeSocket},
-		{0170754, 0754 | fs.ModeIrregular},
-	}
-	for _, tt := range tests {
-		t.Run(tt.mode.String(), func(t *testing.T) {
-			if got := fixMode(tt.mode); got != tt.want {
-				t.Errorf("fixMode() = %o, want %o", got, tt.want)
-			}
-		})
-	}
-}

ext/hash/blake2.go

@@ -0,0 +1,30 @@
+package hash
+
+import (
+	"crypto"
+
+	"github.com/ncruces/go-sqlite3"
+	"github.com/ncruces/go-sqlite3/internal/util"
+)
+
+func blake2sFunc(ctx sqlite3.Context, arg ...sqlite3.Value) {
+	hashFunc(ctx, arg[0], crypto.BLAKE2s_256)
+}
+
+func blake2bFunc(ctx sqlite3.Context, arg ...sqlite3.Value) {
+	size := 512
+	if len(arg) > 1 {
+		size = arg[1].Int()
+	}
+
+	switch size {
+	case 256:
+		hashFunc(ctx, arg[0], crypto.BLAKE2b_256)
+	case 384:
+		hashFunc(ctx, arg[0], crypto.BLAKE2b_384)
+	case 512:
+		hashFunc(ctx, arg[0], crypto.BLAKE2b_512)
+	default:
+		ctx.ResultError(util.ErrorString("blake2b: size must be 256, 384, 512"))
+	}
+}

ext/hash/hash.go

@@ -0,0 +1,97 @@
+// Package hash provides cryptographic hash functions.
+//
+// Provided functions:
+//   - md4(data)
+//   - md5(data)
+//   - sha1(data)
+//   - sha3(data, size) (default size 256)
+//   - sha224(data)
+//   - sha256(data, size) (default size 256)
+//   - sha384(data)
+//   - sha512(data, size) (default size 512)
+//   - blake2s(data)
+//   - blake2b(data, size) (default size 512)
+//   - ripemd160(data)
+//
+// Each SQL function will only be registered if the corresponding
+// [crypto.Hash] function is available.
+// To ensure a specific hash function is available,
+// import the implementing package.
+package hash
+
+import (
+	"crypto"
+
+	"github.com/ncruces/go-sqlite3"
+)
+
+// Register registers cryptographic hash functions for a database connection.
+func Register(db *sqlite3.Conn) {
+	flags := sqlite3.DETERMINISTIC | sqlite3.INNOCUOUS
+
+	if crypto.MD4.Available() {
+		db.CreateFunction("md4", 1, flags, md4Func)
+	}
+	if crypto.MD5.Available() {
+		db.CreateFunction("md5", 1, flags, md5Func)
+	}
+	if crypto.SHA1.Available() {
+		db.CreateFunction("sha1", 1, flags, sha1Func)
+	}
+	if crypto.SHA3_512.Available() {
+		db.CreateFunction("sha3", 1, flags, sha3Func)
+		db.CreateFunction("sha3", 2, flags, sha3Func)
+	}
+	if crypto.SHA256.Available() {
+		db.CreateFunction("sha224", 1, flags, sha224Func)
+		db.CreateFunction("sha256", 1, flags, sha256Func)
+		db.CreateFunction("sha256", 2, flags, sha256Func)
+	}
+	if crypto.SHA512.Available() {
+		db.CreateFunction("sha384", 1, flags, sha384Func)
+		db.CreateFunction("sha512", 1, flags, sha512Func)
+		db.CreateFunction("sha512", 2, flags, sha512Func)
+	}
+	if crypto.BLAKE2s_256.Available() {
+		db.CreateFunction("blake2s", 1, flags, blake2sFunc)
+	}
+	if crypto.BLAKE2b_512.Available() {
+		db.CreateFunction("blake2b", 1, flags, blake2bFunc)
+		db.CreateFunction("blake2b", 2, flags, blake2bFunc)
+	}
+	if crypto.RIPEMD160.Available() {
+		db.CreateFunction("ripemd160", 1, flags, ripemd160Func)
+	}
+}
+
+func md4Func(ctx sqlite3.Context, arg ...sqlite3.Value) {
+	hashFunc(ctx, arg[0], crypto.MD4)
+}
+
+func md5Func(ctx sqlite3.Context, arg ...sqlite3.Value) {
+	hashFunc(ctx, arg[0], crypto.MD5)
+}
+
+func sha1Func(ctx sqlite3.Context, arg ...sqlite3.Value) {
+	hashFunc(ctx, arg[0], crypto.SHA1)
+}
+
+func ripemd160Func(ctx sqlite3.Context, arg ...sqlite3.Value) {
+	hashFunc(ctx, arg[0], crypto.RIPEMD160)
+}
+
+func hashFunc(ctx sqlite3.Context, arg sqlite3.Value, fn crypto.Hash) {
+	var data []byte
+	switch arg.Type() {
+	case sqlite3.NULL:
+		return
+	case sqlite3.BLOB:
+		data = arg.RawBlob()
+	default:
+		data = arg.RawText()
+	}
+
+	h := fn.New()
+	h.Write(data)
+	ctx.ResultBlob(h.Sum(nil))
+}

ext/hash/hash_test.go

@@ -0,0 +1,98 @@
+package hash
+
+import (
+	_ "crypto/md5"
+	_ "crypto/sha1"
+	_ "crypto/sha256"
+	_ "crypto/sha512"
+	"testing"
+
+	"github.com/ncruces/go-sqlite3"
+	"github.com/ncruces/go-sqlite3/driver"
+	_ "github.com/ncruces/go-sqlite3/embed"
+	_ "golang.org/x/crypto/blake2b"
+	_ "golang.org/x/crypto/blake2s"
+	_ "golang.org/x/crypto/md4"
+	_ "golang.org/x/crypto/ripemd160"
+	_ "golang.org/x/crypto/sha3"
+)
+
+func TestRegister(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name string
+		hash string
+	}{
+		{"md4(NULL)", ""},
+		{"md4(X'')", "31D6CFE0D16AE931B73C59D7E0C089C0"},
+		{"md4('The quick brown fox jumps over the lazy dog')", "1BEE69A46BA811185C194762ABAEAE90"},
+
+		{"md5('')", "D41D8CD98F00B204E9800998ECF8427E"},
+		{"sha1('')", "DA39A3EE5E6B4B0D3255BFEF95601890AFD80709"},
+		{"ripemd160('')", "9C1185A5C5E9FC54612808977EE8F548B2258D31"},
+
+		{"sha224('')", "D14A028C2A3A2BC9476102BB288234C415A2B01F828EA62AC5B3E42F"},
+		{"sha256('')", "E3B0C44298FC1C149AFBF4C8996FB92427AE41E4649B934CA495991B7852B855"},
+		{"sha256('', 224)", "D14A028C2A3A2BC9476102BB288234C415A2B01F828EA62AC5B3E42F"},
+		{"sha384('')", "38B060A751AC96384CD9327EB1B1E36A21FDB71114BE07434C0CC7BF63F6E1DA274EDEBFE76F65FBD51AD2F14898B95B"},
+		{"sha512('')", "CF83E1357EEFB8BDF1542850D66D8007D620E4050B5715DC83F4A921D36CE9CE47D0D13C5D85F2B0FF8318D2877EEC2F63B931BD47417A81A538327AF927DA3E"},
+		{"sha512('', 224)", "6ED0DD02806FA89E25DE060C19D3AC86CABB87D6A0DDD05C333B84F4"},
+		{"sha512('', 256)", "C672B8D1EF56ED28AB87C3622C5114069BDD3AD7B8F9737498D0C01ECEF0967A"},
+		{"sha512('', 384)", "38B060A751AC96384CD9327EB1B1E36A21FDB71114BE07434C0CC7BF63F6E1DA274EDEBFE76F65FBD51AD2F14898B95B"},
+
+		{"sha3('')", "A7FFC6F8BF1ED76651C14756A061D662F580FF4DE43B49FA82D80A4B80F8434A"},
+		{"sha3('', 224)", "6B4E03423667DBB73B6E15454F0EB1ABD4597F9A1B078E3F5B5A6BC7"},
+		{"sha3('', 384)", "0C63A75B845E4F7D01107D852E4C2485C51A50AAAA94FC61995E71BBEE983A2AC3713831264ADB47FB6BD1E058D5F004"},
+		{"sha3('', 512)", "A69F73CCA23A9AC5C8B567DC185A756E97C982164FE25859E0D1DCC1475C80A615B2123AF1F5F94C11E3E9402C3AC558F500199D95B6D3E301758586281DCD26"},
+
+		{"blake2s('')", "69217A3079908094E11121D042354A7C1F55B6482CA1A51E1B250DFD1ED0EEF9"},
+		{"blake2b('')", "786A02F742015903C6C6FD852552D272912F4740E15847618A86E217F71F5419D25E1031AFEE585313896444934EB04B903A685B1448B755D56F701AFE9BE2CE"},
+		{"blake2b('', 384)", "B32811423377F52D7862286EE1A72EE540524380FDA1724A6F25D7978C6FD3244A6CAF0498812673C5E05EF583825100"},
+		{"blake2b('', 256)", "0E5751C026E543B2E8AB2EB06099DAA1D1E5DF47778F7787FAAB45CDF12FE3A8"},
+	}
+
+	db, err := driver.Open(":memory:", func(c *sqlite3.Conn) error {
+		Register(c)
+		return nil
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var hash string
+
+			err = db.QueryRow(`SELECT hex(` + tt.name + `)`).Scan(&hash)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			if hash != tt.hash {
+				t.Errorf("got %s, want %s", hash, tt.hash)
+			}
+		})
+	}
+
+	_, err = db.Exec(`SELECT sha256('', 255)`)
+	if err == nil {
+		t.Error("want error")
+	}
+
+	_, err = db.Exec(`SELECT sha512('', 255)`)
+	if err == nil {
+		t.Error("want error")
+	}
+
+	_, err = db.Exec(`SELECT sha3('', 255)`)
+	if err == nil {
+		t.Error("want error")
+	}
+
+	_, err = db.Exec(`SELECT blake2b('', 255)`)
+	if err == nil {
+		t.Error("want error")
+	}
+}

ext/hash/sha2.go

@@ -0,0 +1,53 @@
+package hash
+
+import (
+	"crypto"
+
+	"github.com/ncruces/go-sqlite3"
+	"github.com/ncruces/go-sqlite3/internal/util"
+)
+
+func sha224Func(ctx sqlite3.Context, arg ...sqlite3.Value) {
+	hashFunc(ctx, arg[0], crypto.SHA224)
+}
+
+func sha384Func(ctx sqlite3.Context, arg ...sqlite3.Value) {
+	hashFunc(ctx, arg[0], crypto.SHA384)
+}
+
+func sha256Func(ctx sqlite3.Context, arg ...sqlite3.Value) {
+	size := 256
+	if len(arg) > 1 {
+		size = arg[1].Int()
+	}
+
+	switch size {
+	case 224:
+		hashFunc(ctx, arg[0], crypto.SHA224)
+	case 256:
+		hashFunc(ctx, arg[0], crypto.SHA256)
+	default:
+		ctx.ResultError(util.ErrorString("sha256: size must be 224, 256"))
+	}
+}
+
+func sha512Func(ctx sqlite3.Context, arg ...sqlite3.Value) {
+	size := 512
+	if len(arg) > 1 {
+		size = arg[1].Int()
+	}
+
+	switch size {
+	case 224:
+		hashFunc(ctx, arg[0], crypto.SHA512_224)
+	case 256:
+		hashFunc(ctx, arg[0], crypto.SHA512_256)
+	case 384:
+		hashFunc(ctx, arg[0], crypto.SHA384)
+	case 512:
+		hashFunc(ctx, arg[0], crypto.SHA512)
+	default:
+		ctx.ResultError(util.ErrorString("sha512: size must be 224, 256, 384, 512"))
+	}
+
+}

ext/hash/sha3.go

@@ -0,0 +1,28 @@
+package hash
+
+import (
+	"crypto"
+
+	"github.com/ncruces/go-sqlite3"
+	"github.com/ncruces/go-sqlite3/internal/util"
+)
+
+func sha3Func(ctx sqlite3.Context, arg ...sqlite3.Value) {
+	size := 256
+	if len(arg) > 1 {
+		size = arg[1].Int()
+	}
+
+	switch size {
+	case 224:
+		hashFunc(ctx, arg[0], crypto.SHA3_224)
+	case 256:
+		hashFunc(ctx, arg[0], crypto.SHA3_256)
+	case 384:
+		hashFunc(ctx, arg[0], crypto.SHA3_384)
+	case 512:
+		hashFunc(ctx, arg[0], crypto.SHA3_512)
+	default:
+		ctx.ResultError(util.ErrorString("sha3: size must be 224, 256, 384, 512"))
+	}
+}

ext/lines/lines.go

@@ -15,30 +15,42 @@ import (
 	"bytes"
 	"fmt"
 	"io"
-	"os"
+	"io/fs"
 
 	"github.com/ncruces/go-sqlite3"
+	"github.com/ncruces/go-sqlite3/util/osutil"
 )
 
-// Register registers the lines and lines_read virtual tables.
-// The lines virtual table reads from a database blob or text.
-// The lines_read virtual table reads from a file or an [io.Reader].
+// Register registers the lines and lines_read table-valued functions.
+// The lines function reads from a database blob or text.
+// The lines_read function reads from a file or an [io.Reader].
+// If a filename is specified, [os.Open] is used to open the file.
 func Register(db *sqlite3.Conn) {
+	RegisterFS(db, osutil.FS{})
+}
+
+// RegisterFS registers the lines and lines_read table-valued functions.
+// The lines function reads from a database blob or text.
+// The lines_read function reads from a file or an [io.Reader].
+// If a filename is specified, fsys is used to open the file.
+func RegisterFS(db *sqlite3.Conn, fsys fs.FS) {
 	sqlite3.CreateModule[lines](db, "lines", nil,
 		func(db *sqlite3.Conn, _, _, _ string, _ ...string) (lines, error) {
-			err := db.DeclareVtab(`CREATE TABLE x(line TEXT, data HIDDEN)`)
-			db.VtabConfig(sqlite3.VTAB_INNOCUOUS)
-			return false, err
+			err := db.DeclareVTab(`CREATE TABLE x(line TEXT, data HIDDEN)`)
+			db.VTabConfig(sqlite3.VTAB_INNOCUOUS)
+			return lines{}, err
 		})
 	sqlite3.CreateModule[lines](db, "lines_read", nil,
 		func(db *sqlite3.Conn, _, _, _ string, _ ...string) (lines, error) {
-			err := db.DeclareVtab(`CREATE TABLE x(line TEXT, data HIDDEN)`)
-			db.VtabConfig(sqlite3.VTAB_DIRECTONLY)
-			return true, err
+			err := db.DeclareVTab(`CREATE TABLE x(line TEXT, data HIDDEN)`)
+			db.VTabConfig(sqlite3.VTAB_DIRECTONLY)
+			return lines{fsys}, err
 		})
 }
 
-type lines bool
+type lines struct {
+	fsys fs.FS
+}
 
 func (l lines) BestIndex(idx *sqlite3.IndexInfo) error {
 	for i, cst := range idx.Constraint {
@@ -56,8 +68,8 @@ func (l lines) BestIndex(idx *sqlite3.IndexInfo) error {
 }
 
 func (l lines) Open() (sqlite3.VTabCursor, error) {
-	if l {
-		return &reader{}, nil
+	if l.fsys != nil {
+		return &reader{fsys: l.fsys}, nil
 	} else {
 		return &buffer{}, nil
 	}
@@ -85,6 +97,7 @@ func (c *cursor) Column(ctx *sqlite3.Context, n int) error {
 }
 
 type reader struct {
+	fsys   fs.FS
 	reader *bufio.Reader
 	closer io.Closer
 	cursor
@@ -111,7 +124,7 @@ func (c *reader) Filter(idxNum int, idxStr string, arg ...sqlite3.Value) error {
 			r = p
 		}
 	case sqlite3.TEXT:
-		f, err := os.Open(arg[0].Text())
+		f, err := c.fsys.Open(arg[0].Text())
 		if err != nil {
 			return err
 		}

ext/pivot/pivot.go

@@ -90,7 +90,7 @@ func declare(db *sqlite3.Conn, _, _, _ string, arg ...string) (_ *table, err err
 	}
 
 	create.WriteByte(')')
-	err = db.DeclareVtab(create.String())
+	err = db.DeclareVTab(create.String())
 	if err != nil {
 		return nil, err
 	}
@@ -142,6 +142,8 @@ func (t *table) BestIndex(idx *sqlite3.IndexInfo) error {
 		}
 		idxStr.WriteString(sep)
 		idxStr.WriteString(t.keys[ord.Column])
+		idxStr.WriteString(" COLLATE ")
+		idxStr.WriteString(idx.Collation(ord.Column))
 		if ord.Desc {
 			idxStr.WriteString(" DESC")
 		}

ext/statement/stmt.go

@@ -67,7 +67,7 @@ func declare(db *sqlite3.Conn, _, _, _ string, arg ...string) (*table, error) {
 	}
 	str.WriteByte(')')
 
-	err = db.DeclareVtab(str.String())
+	err = db.DeclareVTab(str.String())
 	if err != nil {
 		stmt.Close()
 		return nil, err

ext/stats/TODO.md

@@ -0,0 +1,47 @@
+# ANSI SQL Aggregate Functions
+
+https://www.oreilly.com/library/view/sql-in-a/9780596155322/ch04s02.html
+
+## Built in aggregates
+
+- [x] `COUNT(*)`
+- [x] `COUNT(expression)`
+- [x] `SUM(expression)`
+- [x] `AVG(expression)`
+- [x] `MIN(expression)`
+- [x] `MAX(expression)`
+
+https://sqlite.org/lang_aggfunc.html
+
+## Statistical aggregates
+
+- [x] `STDDEV_POP(expression)`
+- [x] `STDDEV_SAMP(expression)`
+- [x] `VAR_POP(expression)`
+- [x] `VAR_SAMP(expression)`
+- [x] `COVAR_POP(dependent, independent)`
+- [x] `COVAR_SAMP(dependent, independent)`
+- [x] `CORR(dependent, independent)`
+
+## Linear regression aggregates
+
+- [X] `REGR_AVGX(dependent, independent)`
+- [X] `REGR_AVGY(dependent, independent)`
+- [X] `REGR_SXX(dependent, independent)`
+- [X] `REGR_SYY(dependent, independent)`
+- [X] `REGR_SXY(dependent, independent)`
+- [X] `REGR_COUNT(dependent, independent)`
+- [X] `REGR_SLOPE(dependent, independent)`
+- [X] `REGR_INTERCEPT(dependent, independent)`
+- [X] `REGR_R2(dependent, independent)`
+
+## Set aggregates
+
+- [X] `CUME_DIST() OVER window`
+- [X] `RANK() OVER window`
+- [X] `DENSE_RANK() OVER window`
+- [X] `PERCENT_RANK() OVER window`
+- [ ] `PERCENTILE_CONT(percentile) OVER window`
+- [ ] `PERCENTILE_DISC(percentile) OVER window`
+
+https://sqlite.org/windowfunctions.html#builtins

ext/stats/stats.go

@@ -1,6 +1,6 @@
 // Package stats provides aggregate functions for statistics.
 //
-// Functions:
+// Provided functions:
 //   - stddev_pop: population standard deviation
 //   - stddev_samp: sample standard deviation
 //   - var_pop: population variance
@@ -8,9 +8,26 @@
 //   - covar_pop: population covariance
 //   - covar_samp: sample covariance
 //   - corr: correlation coefficient
+//   - regr_r2: correlation coefficient squared
+//   - regr_avgx: average of the independent variable
+//   - regr_avgy: average of the dependent variable
+//   - regr_sxx: sum of the squares of the independent variable
+//   - regr_syy: sum of the squares of the dependent variable
+//   - regr_sxy: sum of the products of each pair of variables
+//   - regr_count: count non-null pairs of variables
+//   - regr_slope: slope of the least-squares-fit linear equation
+//   - regr_intercept: y-intercept of the least-squares-fit linear equation
+//
+// These join the [Built-in Aggregate Functions]:
+//   - count: count rows/values
+//   - sum: sum values
+//   - avg: average value
+//   - min: minimum value
+//   - max: maximum value
 //
 // See: [ANSI SQL Aggregate Functions]
 //
+// [Built-in Aggregate Functions]: https://sqlite.org/lang_aggfunc.html
 // [ANSI SQL Aggregate Functions]: https://www.oreilly.com/library/view/sql-in-a/9780596155322/ch04s02.html
 package stats
 
@@ -26,6 +43,15 @@ func Register(db *sqlite3.Conn) {
 	db.CreateWindowFunction("covar_pop", 2, flags, newCovariance(var_pop))
 	db.CreateWindowFunction("covar_samp", 2, flags, newCovariance(var_samp))
 	db.CreateWindowFunction("corr", 2, flags, newCovariance(corr))
+	db.CreateWindowFunction("regr_r2", 2, flags, newCovariance(regr_r2))
+	db.CreateWindowFunction("regr_sxx", 2, flags, newCovariance(regr_sxx))
+	db.CreateWindowFunction("regr_syy", 2, flags, newCovariance(regr_syy))
+	db.CreateWindowFunction("regr_sxy", 2, flags, newCovariance(regr_sxy))
+	db.CreateWindowFunction("regr_avgx", 2, flags, newCovariance(regr_avgx))
+	db.CreateWindowFunction("regr_avgy", 2, flags, newCovariance(regr_avgy))
+	db.CreateWindowFunction("regr_slope", 2, flags, newCovariance(regr_slope))
+	db.CreateWindowFunction("regr_intercept", 2, flags, newCovariance(regr_intercept))
+	db.CreateWindowFunction("regr_count", 2, flags, newCovariance(regr_count))
 }
 
 const (
@@ -34,6 +60,15 @@ const (
 	stddev_pop
 	stddev_samp
 	corr
+	regr_r2
+	regr_sxx
+	regr_syy
+	regr_sxy
+	regr_avgx
+	regr_avgy
+	regr_slope
+	regr_intercept
+	regr_count
 )
 
 func newVariance(kind int) func() sqlite3.AggregateFunction {
@@ -61,13 +96,13 @@ func (fn *variance) Value(ctx sqlite3.Context) {
 }
 
 func (fn *variance) Step(ctx sqlite3.Context, arg ...sqlite3.Value) {
-	if a := arg[0]; a.Type() != sqlite3.NULL {
+	if a := arg[0]; a.NumericType() != sqlite3.NULL {
 		fn.enqueue(a.Float())
 	}
 }
 
 func (fn *variance) Inverse(ctx sqlite3.Context, arg ...sqlite3.Value) {
-	if a := arg[0]; a.Type() != sqlite3.NULL {
+	if a := arg[0]; a.NumericType() != sqlite3.NULL {
 		fn.dequeue(a.Float())
 	}
 }
@@ -90,20 +125,39 @@ func (fn *covariance) Value(ctx sqlite3.Context) {
 		r = fn.covar_samp()
 	case corr:
 		r = fn.correlation()
+	case regr_r2:
+		r = fn.regr_r2()
+	case regr_sxx:
+		r = fn.regr_sxx()
+	case regr_syy:
+		r = fn.regr_syy()
+	case regr_sxy:
+		r = fn.regr_sxy()
+	case regr_avgx:
+		r = fn.regr_avgx()
+	case regr_avgy:
+		r = fn.regr_avgy()
+	case regr_slope:
+		r = fn.regr_slope()
+	case regr_intercept:
+		r = fn.regr_intercept()
+	case regr_count:
+		ctx.ResultInt64(fn.regr_count())
+		return
 	}
 	ctx.ResultFloat(r)
 }
 
 func (fn *covariance) Step(ctx sqlite3.Context, arg ...sqlite3.Value) {
 	a, b := arg[0], arg[1]
-	if a.Type() != sqlite3.NULL && b.Type() != sqlite3.NULL {
+	if a.NumericType() != sqlite3.NULL && b.NumericType() != sqlite3.NULL {
 		fn.enqueue(a.Float(), b.Float())
 	}
 }
 
 func (fn *covariance) Inverse(ctx sqlite3.Context, arg ...sqlite3.Value) {
 	a, b := arg[0], arg[1]
-	if a.Type() != sqlite3.NULL && b.Type() != sqlite3.NULL {
+	if a.NumericType() != sqlite3.NULL && b.NumericType() != sqlite3.NULL {
 		fn.dequeue(a.Float(), b.Float())
 	}
 }

ext/stats/stats_test.go

@@ -92,18 +92,23 @@ func TestRegister_covariance(t *testing.T) {
 
 	stats.Register(db)
 
-	err = db.Exec(`CREATE TABLE IF NOT EXISTS data (x, y)`)
+	err = db.Exec(`CREATE TABLE IF NOT EXISTS data (y, x)`)
 	if err != nil {
 		t.Fatal(err)
 	}
 
-	err = db.Exec(`INSERT INTO data (x, y) VALUES (3, 70), (5, 80), (2, 60), (7, 90), (4, 75)`)
+	err = db.Exec(`INSERT INTO data (y, x) VALUES (3, 70), (5, 80), (2, 60), (7, 90), (4, 75)`)
 	if err != nil {
 		t.Fatal(err)
 	}
 
 	stmt, _, err := db.Prepare(`SELECT
-		corr(x, y), covar_samp(x, y), covar_pop(x, y) FROM data`)
+		corr(y, x), covar_samp(y, x), covar_pop(y, x),
+		regr_avgy(y, x), regr_avgx(y, x),
+		regr_syy(y, x), regr_sxx(y, x), regr_sxy(y, x),
+		regr_slope(y, x), regr_intercept(y, x), regr_r2(y, x),
+		regr_count(y, x)
+		FROM data`)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -119,10 +124,37 @@ func TestRegister_covariance(t *testing.T) {
 		if got := stmt.ColumnFloat(2); got != 17 {
 			t.Errorf("got %v, want 17", got)
 		}
+		if got := stmt.ColumnFloat(3); got != 4.2 {
+			t.Errorf("got %v, want 4.2", got)
+		}
+		if got := stmt.ColumnFloat(4); got != 75 {
+			t.Errorf("got %v, want 75", got)
+		}
+		if got := stmt.ColumnFloat(5); got != 14.8 {
+			t.Errorf("got %v, want 14.8", got)
+		}
+		if got := stmt.ColumnFloat(6); got != 500 {
+			t.Errorf("got %v, want 500", got)
+		}
+		if got := stmt.ColumnFloat(7); got != 85 {
+			t.Errorf("got %v, want 85", got)
+		}
+		if got := stmt.ColumnFloat(8); got != 0.17 {
+			t.Errorf("got %v, want 0.17", got)
+		}
+		if got := stmt.ColumnFloat(9); got != -8.55 {
+			t.Errorf("got %v, want -8.55", got)
+		}
+		if got := stmt.ColumnFloat(10); got != 0.9763513513513513 {
+			t.Errorf("got %v, want 0.9763513513513513", got)
+		}
+		if got := stmt.ColumnInt(11); got != 5 {
+			t.Errorf("got %v, want 5", got)
+		}
 	}
 
 	{
-		stmt, _, err := db.Prepare(`SELECT covar_samp(x, y) OVER (ROWS 1 PRECEDING) FROM data`)
+		stmt, _, err := db.Prepare(`SELECT covar_samp(y, x) OVER (ROWS 1 PRECEDING) FROM data`)
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -139,3 +171,67 @@ func TestRegister_covariance(t *testing.T) {
 		}
 	}
 }
+
+func Benchmark_average(b *testing.B) {
+	db, err := sqlite3.Open(":memory:")
+	if err != nil {
+		b.Fatal(err)
+	}
+	defer db.Close()
+
+	stmt, _, err := db.Prepare(`SELECT avg(value) FROM generate_series(0, ?)`)
+	if err != nil {
+		b.Fatal(err)
+	}
+	defer stmt.Close()
+
+	err = stmt.BindInt(1, b.N)
+	if err != nil {
+		b.Fatal(err)
+	}
+
+	if stmt.Step() {
+		want := float64(b.N) / 2
+		if got := stmt.ColumnFloat(0); got != want {
+			b.Errorf("got %v, want %v", got, want)
+		}
+	}
+
+	err = stmt.Err()
+	if err != nil {
+		b.Error(err)
+	}
+}
+
+func Benchmark_variance(b *testing.B) {
+	db, err := sqlite3.Open(":memory:")
+	if err != nil {
+		b.Fatal(err)
+	}
+	defer db.Close()
+
+	stats.Register(db)
+
+	stmt, _, err := db.Prepare(`SELECT var_pop(value) FROM generate_series(0, ?)`)
+	if err != nil {
+		b.Fatal(err)
+	}
+	defer stmt.Close()
+
+	err = stmt.BindInt(1, b.N)
+	if err != nil {
+		b.Fatal(err)
+	}
+
+	if stmt.Step() && b.N > 100 {
+		want := float64(b.N*b.N) / 12
+		if got := stmt.ColumnFloat(0); want > (got-want)*float64(b.N) {
+			b.Errorf("got %v, want %v", got, want)
+		}
+	}
+
+	err = stmt.Err()
+	if err != nil {
+		b.Error(err)
+	}
+}

ext/stats/welford.go

@@ -6,9 +6,12 @@ import "math"
 // https://en.wikipedia.org/wiki/Algorithms_for_calculating_variance#Welford's_online_algorithm
 // https://en.wikipedia.org/wiki/Kahan_summation_algorithm
 
+// See also:
+// https://duckdb.org/docs/sql/aggregates.html#statistical-aggregates
+
 type welford struct {
 	m1, m2 kahan
-	n      uint64
+	n      int64
 }
 
 func (w welford) average() float64 {
@@ -48,10 +51,10 @@ func (w *welford) dequeue(x float64) {
 }
 
 type welford2 struct {
-	m1x, m2x kahan
 	m1y, m2y kahan
+	m1x, m2x kahan
 	cov      kahan
-	n        uint64
+	n        int64
 }
 
 func (w welford2) covar_pop() float64 {
@@ -63,33 +66,72 @@ func (w welford2) covar_samp() float64 {
 }
 
 func (w welford2) correlation() float64 {
-	return w.cov.hi / math.Sqrt(w.m2x.hi*w.m2y.hi)
+	return w.cov.hi / math.Sqrt(w.m2y.hi*w.m2x.hi)
 }
 
-func (w *welford2) enqueue(x, y float64) {
+func (w welford2) regr_avgy() float64 {
+	return w.m1y.hi
+}
+
+func (w welford2) regr_avgx() float64 {
+	return w.m1x.hi
+}
+
+func (w welford2) regr_syy() float64 {
+	return w.m2y.hi
+}
+
+func (w welford2) regr_sxx() float64 {
+	return w.m2x.hi
+}
+
+func (w welford2) regr_sxy() float64 {
+	return w.cov.hi
+}
+
+func (w welford2) regr_count() int64 {
+	return w.n
+}
+
+func (w welford2) regr_slope() float64 {
+	return w.cov.hi / w.m2x.hi
+}
+
+func (w welford2) regr_intercept() float64 {
+	slope := -w.regr_slope()
+	hi := math.FMA(slope, w.m1x.hi, w.m1y.hi)
+	lo := math.FMA(slope, w.m1x.lo, w.m1y.lo)
+	return hi + lo
+}
+
+func (w welford2) regr_r2() float64 {
+	return w.cov.hi * w.cov.hi / (w.m2y.hi * w.m2x.hi)
+}
+
+func (w *welford2) enqueue(y, x float64) {
 	w.n++
-	d1x := x - w.m1x.hi - w.m1x.lo
 	d1y := y - w.m1y.hi - w.m1y.lo
-	w.m1x.add(d1x / float64(w.n))
+	d1x := x - w.m1x.hi - w.m1x.lo
 	w.m1y.add(d1y / float64(w.n))
-	d2x := x - w.m1x.hi - w.m1x.lo
+	w.m1x.add(d1x / float64(w.n))
 	d2y := y - w.m1y.hi - w.m1y.lo
-	w.m2x.add(d1x * d2x)
+	d2x := x - w.m1x.hi - w.m1x.lo
 	w.m2y.add(d1y * d2y)
-	w.cov.add(d1x * d2y)
+	w.m2x.add(d1x * d2x)
+	w.cov.add(d1y * d2x)
 }
 
-func (w *welford2) dequeue(x, y float64) {
+func (w *welford2) dequeue(y, x float64) {
 	w.n--
-	d1x := x - w.m1x.hi - w.m1x.lo
 	d1y := y - w.m1y.hi - w.m1y.lo
-	w.m1x.sub(d1x / float64(w.n))
+	d1x := x - w.m1x.hi - w.m1x.lo
 	w.m1y.sub(d1y / float64(w.n))
-	d2x := x - w.m1x.hi - w.m1x.lo
+	w.m1x.sub(d1x / float64(w.n))
 	d2y := y - w.m1y.hi - w.m1y.lo
-	w.m2x.sub(d1x * d2x)
+	d2x := x - w.m1x.hi - w.m1x.lo
 	w.m2y.sub(d1y * d2y)
-	w.cov.sub(d1x * d2y)
+	w.m2x.sub(d1x * d2x)
+	w.cov.sub(d1y * d2x)
 }
 
 type kahan struct{ hi, lo float64 }

ext/todo.txt

@@ -1,16 +0,0 @@
-sha3
-sha3_query
-
-ieee754
-ieee754_exponent
-ieee754_from_blob
-ieee754_inc
-ieee754_mantissa
-ieee754_to_blob
-
-zipfile
-zipfile_cds
-sqlar_compress
-sqlar_uncompress
-
-remember

ext/unicode/unicode.go

@@ -8,7 +8,7 @@
 // The implementation is not 100% compatible with the [ICU extension]:
 //   - upper() and lower() use [strings.ToUpper], [strings.ToLower] and [cases];
 //   - the LIKE operator follows [strings.EqualFold] rules;
-//   - the REGEXP operator uses Go [regex/syntax];
+//   - the REGEXP operator uses Go [regexp/syntax];
 //   - collation sequences use [collate].
 //
 // Expect subtle differences (e.g.) in the handling of Turkish case folding.

func.go

@@ -2,6 +2,7 @@ package sqlite3
 
 import (
 	"context"
+	"sync"
 
 	"github.com/ncruces/go-sqlite3/internal/util"
 	"github.com/tetratelabs/wazero/api"
@@ -43,6 +44,7 @@ func (c *Conn) CreateFunction(name string, nArg int, flag FunctionFlag, fn Scala
 }
 
 // ScalarFunction is the type of a scalar SQL function.
+// Implementations must not retain arg.
 type ScalarFunction func(ctx Context, arg ...Value)
 
 // CreateWindowFunction defines a new aggregate or aggregate window SQL function.
@@ -69,7 +71,8 @@ func (c *Conn) CreateWindowFunction(name string, nArg int, flag FunctionFlag, fn
 // https://sqlite.org/appfunc.html
 type AggregateFunction interface {
 	// Step is invoked to add a row to the current window.
-	// The function arguments, if any, corresponding to the row being added are passed to Step.
+	// The function arguments, if any, corresponding to the row being added, are passed to Step.
+	// Implementations must not retain arg.
 	Step(ctx Context, arg ...Value)
 
 	// Value is invoked to return the current (or final) value of the aggregate.
@@ -84,9 +87,21 @@ type WindowFunction interface {
 
 	// Inverse is invoked to remove the oldest presently aggregated result of Step from the current window.
 	// The function arguments, if any, are those passed to Step for the row being removed.
+	// Implementations must not retain arg.
 	Inverse(ctx Context, arg ...Value)
 }
 
+// OverloadFunction overloads a function for a virtual table.
+//
+// https://sqlite.org/c3ref/overload_function.html
+func (c *Conn) OverloadFunction(name string, nArg int) error {
+	defer c.arena.mark()()
+	namePtr := c.arena.string(name)
+	r := c.call("sqlite3_overload_function",
+		uint64(c.handle), uint64(namePtr), uint64(nArg))
+	return c.error(r)
+}
+
 func destroyCallback(ctx context.Context, mod api.Module, pApp uint32) {
 	util.DelHandle(ctx, pApp)
 }
@@ -96,80 +111,80 @@ func compareCallback(ctx context.Context, mod api.Module, pApp, nKey1, pKey1, nK
 	return uint32(fn(util.View(mod, pKey1, uint64(nKey1)), util.View(mod, pKey2, uint64(nKey2))))
 }
 
-func funcCallback(ctx context.Context, mod api.Module, pCtx, nArg, pArg uint32) {
+func funcCallback(ctx context.Context, mod api.Module, pCtx, pApp, nArg, pArg uint32) {
+	args := getFuncArgs()
+	defer putFuncArgs(args)
 	db := ctx.Value(connKey{}).(*Conn)
-	fn := userDataHandle(db, pCtx).(ScalarFunction)
-	fn(Context{db, pCtx}, callbackArgs(db, nArg, pArg)...)
+	fn := util.GetHandle(db.ctx, pApp).(ScalarFunction)
+	callbackArgs(db, args[:nArg], pArg)
+	fn(Context{db, pCtx}, args[:nArg]...)
 }
 
-func stepCallback(ctx context.Context, mod api.Module, pCtx, nArg, pArg uint32) {
+func stepCallback(ctx context.Context, mod api.Module, pCtx, pAgg, pApp, nArg, pArg uint32) {
+	args := getFuncArgs()
+	defer putFuncArgs(args)
 	db := ctx.Value(connKey{}).(*Conn)
-	fn := aggregateCtxHandle(db, pCtx, nil)
-	fn.Step(Context{db, pCtx}, callbackArgs(db, nArg, pArg)...)
+	callbackArgs(db, args[:nArg], pArg)
+	fn, _ := callbackAggregate(db, pAgg, pApp)
+	fn.Step(Context{db, pCtx}, args[:nArg]...)
 }
 
-func finalCallback(ctx context.Context, mod api.Module, pCtx uint32) {
-	var handle uint32
+func finalCallback(ctx context.Context, mod api.Module, pCtx, pAgg, pApp uint32) {
 	db := ctx.Value(connKey{}).(*Conn)
-	fn := aggregateCtxHandle(db, pCtx, &handle)
+	fn, handle := callbackAggregate(db, pAgg, pApp)
 	fn.Value(Context{db, pCtx})
-	if err := util.DelHandle(ctx, handle); err != nil {
-		Context{db, pCtx}.ResultError(err)
-	}
+	util.DelHandle(ctx, handle)
 }
 
-func valueCallback(ctx context.Context, mod api.Module, pCtx uint32) {
+func valueCallback(ctx context.Context, mod api.Module, pCtx, pAgg uint32) {
 	db := ctx.Value(connKey{}).(*Conn)
-	fn := aggregateCtxHandle(db, pCtx, nil)
+	fn := util.GetHandle(db.ctx, pAgg).(AggregateFunction)
 	fn.Value(Context{db, pCtx})
 }
 
-func inverseCallback(ctx context.Context, mod api.Module, pCtx, nArg, pArg uint32) {
+func inverseCallback(ctx context.Context, mod api.Module, pCtx, pAgg, nArg, pArg uint32) {
+	args := getFuncArgs()
+	defer putFuncArgs(args)
 	db := ctx.Value(connKey{}).(*Conn)
-	fn := aggregateCtxHandle(db, pCtx, nil).(WindowFunction)
-	fn.Inverse(Context{db, pCtx}, callbackArgs(db, nArg, pArg)...)
+	callbackArgs(db, args[:nArg], pArg)
+	fn := util.GetHandle(db.ctx, pAgg).(WindowFunction)
+	fn.Inverse(Context{db, pCtx}, args[:nArg]...)
 }
 
-func userDataHandle(db *Conn, pCtx uint32) any {
-	pApp := uint32(db.call("sqlite3_user_data", uint64(pCtx)))
-	return util.GetHandle(db.ctx, pApp)
+func callbackAggregate(db *Conn, pAgg, pApp uint32) (AggregateFunction, uint32) {
+	if pApp == 0 {
+		handle := util.ReadUint32(db.mod, pAgg)
+		return util.GetHandle(db.ctx, handle).(AggregateFunction), handle
+	}
+
+	// We need to create the aggregate.
+	fn := util.GetHandle(db.ctx, pApp).(func() AggregateFunction)()
+	handle := util.AddHandle(db.ctx, fn)
+	if pAgg != 0 {
+		util.WriteUint32(db.mod, pAgg, handle)
+	}
+	return fn, handle
 }
 
-func aggregateCtxHandle(db *Conn, pCtx uint32, close *uint32) AggregateFunction {
-	// On close, we're getting rid of the aggregate.
-	// Don't allocate space to store it.
-	var size uint64
-	if close == nil {
-		size = ptrlen
-	}
-	ptr := uint32(db.call("sqlite3_aggregate_context", uint64(pCtx), size))
-
-	// If we already have an aggregate, return it.
-	if ptr != 0 {
-		if handle := util.ReadUint32(db.mod, ptr); handle != 0 {
-			fn := util.GetHandle(db.ctx, handle).(AggregateFunction)
-			if close != nil {
-				*close = handle
-			}
-			return fn
-		}
-	}
-
-	// Create a new aggregate, and store it if needed.
-	fn := userDataHandle(db, pCtx).(func() AggregateFunction)()
-	if ptr != 0 {
-		util.WriteUint32(db.mod, ptr, util.AddHandle(db.ctx, fn))
-	}
-	return fn
-}
-
-func callbackArgs(db *Conn, nArg, pArg uint32) []Value {
-	args := make([]Value, nArg)
-	for i := range args {
-		args[i] = Value{
-			sqlite: db.sqlite,
+func callbackArgs(db *Conn, arg []Value, pArg uint32) {
+	for i := range arg {
+		arg[i] = Value{
+			c:      db,
 			handle: util.ReadUint32(db.mod, pArg+ptrlen*uint32(i)),
 		}
 	}
-	return args
+}
+
+var funcArgsPool sync.Pool
+
+func putFuncArgs(p *[_MAX_FUNCTION_ARG]Value) {
+	funcArgsPool.Put(p)
+}
+
+func getFuncArgs() *[_MAX_FUNCTION_ARG]Value {
+	if p := funcArgsPool.Get(); p == nil {
+		return new([_MAX_FUNCTION_ARG]Value)
+	} else {
+		return p.(*[_MAX_FUNCTION_ARG]Value)
+	}
 }

go.mod

@@ -5,9 +5,10 @@ go 1.21
 require (
 	github.com/ncruces/julianday v1.0.0
 	github.com/psanford/httpreadat v0.1.0
-	github.com/tetratelabs/wazero v1.5.0
-	golang.org/x/sync v0.5.0
-	golang.org/x/sys v0.15.0
+	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
 	golang.org/x/text v0.14.0
 )
 

go.sum

@@ -2,11 +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 v1.5.0 h1:Yz3fZHivfDiZFUXnWMPUoiW7s8tC1sjdBtlJn08qYa0=
-github.com/tetratelabs/wazero v1.5.0/go.mod h1:0U0G41+ochRKoPKCJlh0jMg1CHkyfK8kDqiirMmKY8A=
-golang.org/x/sync v0.5.0 h1:60k92dhOjHxJkrqnwsfl8KuaHbn/5dl0lUPUklKo3qE=
-golang.org/x/sync v0.5.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
-golang.org/x/sys v0.15.0 h1:h48lPFYpsTvQJZF4EKyI4aLHaev3CxivZmv7yZig9pc=
-golang.org/x/sys v0.15.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+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=
 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

@@ -1,4 +1,3 @@
-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/tools v0.6.0 h1:BOw41kyTf3PuCW1pVQf8+Cyg8pMlkYB1oo9iJ6D/lKM=
+golang.org/x/net v0.10.0/go.mod h1:0qNGK6F8kojg2nk9dLZ2mShWaEBan6FAoqfSigmmuDg=
 golang.org/x/tools v0.6.0/go.mod h1:Xwgl3UAJ/d3gWutnCtw505GrjyAbvKui8lOU390QaIU=

internal/util/func.go

@@ -23,6 +23,19 @@ func ExportFuncVI[T0 i32](mod wazero.HostModuleBuilder, name string, fn func(con
 		Export(name)
 }
 
+type funcVII[T0, T1 i32] func(context.Context, api.Module, T0, T1)
+
+func (fn funcVII[T0, T1]) Call(ctx context.Context, mod api.Module, stack []uint64) {
+	fn(ctx, mod, T0(stack[0]), T1(stack[1]))
+}
+
+func ExportFuncVII[T0, T1 i32](mod wazero.HostModuleBuilder, name string, fn func(context.Context, api.Module, T0, T1)) {
+	mod.NewFunctionBuilder().
+		WithGoModuleFunction(funcVII[T0, T1](fn),
+			[]api.ValueType{api.ValueTypeI32, api.ValueTypeI32}, nil).
+		Export(name)
+}
+
 type funcVIII[T0, T1, T2 i32] func(context.Context, api.Module, T0, T1, T2)
 
 func (fn funcVIII[T0, T1, T2]) Call(ctx context.Context, mod api.Module, stack []uint64) {
@@ -36,6 +49,32 @@ func ExportFuncVIII[T0, T1, T2 i32](mod wazero.HostModuleBuilder, name string, f
 		Export(name)
 }
 
+type funcVIIII[T0, T1, T2, T3 i32] func(context.Context, api.Module, T0, T1, T2, T3)
+
+func (fn funcVIIII[T0, T1, T2, T3]) Call(ctx context.Context, mod api.Module, stack []uint64) {
+	fn(ctx, mod, T0(stack[0]), T1(stack[1]), T2(stack[2]), T3(stack[3]))
+}
+
+func ExportFuncVIIII[T0, T1, T2, T3 i32](mod wazero.HostModuleBuilder, name string, fn func(context.Context, api.Module, T0, T1, T2, T3)) {
+	mod.NewFunctionBuilder().
+		WithGoModuleFunction(funcVIIII[T0, T1, T2, T3](fn),
+			[]api.ValueType{api.ValueTypeI32, api.ValueTypeI32, api.ValueTypeI32, api.ValueTypeI32}, nil).
+		Export(name)
+}
+
+type funcVIIIII[T0, T1, T2, T3, T4 i32] func(context.Context, api.Module, T0, T1, T2, T3, T4)
+
+func (fn funcVIIIII[T0, T1, T2, T3, T4]) Call(ctx context.Context, mod api.Module, stack []uint64) {
+	fn(ctx, mod, T0(stack[0]), T1(stack[1]), T2(stack[2]), T3(stack[3]), T4(stack[4]))
+}
+
+func ExportFuncVIIIII[T0, T1, T2, T3, T4 i32](mod wazero.HostModuleBuilder, name string, fn func(context.Context, api.Module, T0, T1, T2, T3, T4)) {
+	mod.NewFunctionBuilder().
+		WithGoModuleFunction(funcVIIIII[T0, T1, T2, T3, T4](fn),
+			[]api.ValueType{api.ValueTypeI32, api.ValueTypeI32, api.ValueTypeI32, api.ValueTypeI32, api.ValueTypeI32}, nil).
+		Export(name)
+}
+
 type funcII[TR, T0 i32] func(context.Context, api.Module, T0) TR
 
 func (fn funcII[TR, T0]) Call(ctx context.Context, mod api.Module, stack []uint64) {

internal/util/json.go

@@ -0,0 +1,35 @@
+package util
+
+import (
+	"encoding/json"
+	"strconv"
+	"time"
+	"unsafe"
+)
+
+type JSON struct{ Value any }
+
+func (j JSON) Scan(value any) error {
+	var buf []byte
+
+	switch v := value.(type) {
+	case []byte:
+		buf = v
+	case string:
+		buf = unsafe.Slice(unsafe.StringData(v), len(v))
+	case int64:
+		buf = strconv.AppendInt(nil, v, 10)
+	case float64:
+		buf = strconv.AppendFloat(nil, v, 'g', -1, 64)
+	case time.Time:
+		buf = append(buf, '"')
+		buf = v.AppendFormat(buf, time.RFC3339Nano)
+		buf = append(buf, '"')
+	case nil:
+		buf = append(buf, "null"...)
+	default:
+		panic(AssertErr())
+	}
+
+	return json.Unmarshal(buf, j.Value)
+}

internal/util/pointer.go

@@ -0,0 +1,11 @@
+package util
+
+type Pointer[T any] struct{ Value T }
+
+func (p Pointer[T]) unwrap() any { return p.Value }
+
+type PointerUnwrap interface{ unwrap() any }
+
+func UnwrapPointer(p PointerUnwrap) any {
+	return p.unwrap()
+}

internal/util/pointer_test.go

@@ -0,0 +1,15 @@
+package util_test
+
+import (
+	"math"
+	"testing"
+
+	"github.com/ncruces/go-sqlite3/internal/util"
+)
+
+func TestUnwrapPointer(t *testing.T) {
+	p := util.Pointer[float64]{Value: math.Pi}
+	if got := util.UnwrapPointer(p); got != math.Pi {
+		t.Errorf("want π, got %v", got)
+	}
+}

internal/util/reflect.go

@@ -0,0 +1,10 @@
+package util
+
+import "reflect"
+
+func ReflectType(v reflect.Value) reflect.Type {
+	if v.Kind() != reflect.Invalid {
+		return v.Type()
+	}
+	return nil
+}

internal/util/reflect_test.go

@@ -0,0 +1,21 @@
+package util
+
+import (
+	"fmt"
+	"math"
+	"reflect"
+	"testing"
+)
+
+func TestReflectType(t *testing.T) {
+	tests := []any{nil, 1, math.Pi, "abc"}
+	for _, tt := range tests {
+		t.Run(fmt.Sprint(tt), func(t *testing.T) {
+			want := fmt.Sprintf("%T", tt)
+			got := fmt.Sprintf("%v", ReflectType(reflect.ValueOf(tt)))
+			if got != want {
+				t.Errorf("ReflectType() = %v, want %v", got, want)
+			}
+		})
+	}
+}

json.go

@@ -1,46 +1,11 @@
 package sqlite3
 
-import (
-	"encoding/json"
-	"strconv"
-	"time"
-	"unsafe"
-
-	"github.com/ncruces/go-sqlite3/internal/util"
-)
+import "github.com/ncruces/go-sqlite3/internal/util"
 
 // JSON returns a value that can be used as an argument to
 // [database/sql.DB.Exec], [database/sql.Row.Scan] and similar methods to
 // store value as JSON, or decode JSON into value.
+// JSON should NOT be used with [BindJSON] or [ResultJSON].
 func JSON(value any) any {
-	return jsonValue{value}
-}
-
-type jsonValue struct{ any }
-
-func (j jsonValue) JSON() any { return j.any }
-
-func (j jsonValue) Scan(value any) error {
-	var buf []byte
-
-	switch v := value.(type) {
-	case []byte:
-		buf = v
-	case string:
-		buf = unsafe.Slice(unsafe.StringData(v), len(v))
-	case int64:
-		buf = strconv.AppendInt(nil, v, 10)
-	case float64:
-		buf = strconv.AppendFloat(nil, v, 'g', -1, 64)
-	case time.Time:
-		buf = append(buf, '"')
-		buf = v.AppendFormat(buf, time.RFC3339Nano)
-		buf = append(buf, '"')
-	case nil:
-		buf = append(buf, "null"...)
-	default:
-		panic(util.AssertErr())
-	}
-
-	return json.Unmarshal(buf, j.any)
+	return util.JSON{Value: value}
 }

pointer.go

@@ -1,14 +1,12 @@
 package sqlite3
 
-// Pointer returns a pointer to a value
-// that can be used as an argument to
+import "github.com/ncruces/go-sqlite3/internal/util"
+
+// Pointer returns a pointer to a value that can be used as an argument to
 // [database/sql.DB.Exec] and similar methods.
+// Pointer should NOT be used with [BindPointer] or [ResultPointer].
 //
 // https://sqlite.org/bindptr.html
-func Pointer[T any](val T) any {
-	return pointer[T]{val}
+func Pointer[T any](value T) any {
+	return util.Pointer[T]{Value: value}
 }
-
-type pointer[T any] struct{ val T }
-
-func (p pointer[T]) Pointer() any { return p.val }

sqlite.go

@@ -126,7 +126,7 @@ func (sqlt *sqlite) error(rc uint64, handle uint32, sql ...string) error {
 
 	if handle != 0 {
 		if r := sqlt.call("sqlite3_errmsg", uint64(handle)); r != 0 {
-			err.msg = util.ReadString(sqlt.mod, uint32(r), _MAX_NAME)
+			err.msg = util.ReadString(sqlt.mod, uint32(r), _MAX_LENGTH)
 		}
 
 		if sql != nil {
@@ -216,6 +216,8 @@ func (sqlt *sqlite) newString(s string) uint32 {
 }
 
 func (sqlt *sqlite) newArena(size uint64) arena {
+	// Ensure the arena's size is a multiple of 8.
+	size = (size + 7) &^ 7
 	return arena{
 		sqlt: sqlt,
 		size: uint32(size),
@@ -255,6 +257,12 @@ func (a *arena) mark() (reset func()) {
 }
 
 func (a *arena) new(size uint64) uint32 {
+	// Align the next address, to 4 or 8 bytes.
+	if size&7 != 0 {
+		a.next = (a.next + 3) &^ 3
+	} else {
+		a.next = (a.next + 7) &^ 7
+	}
 	if size <= uint64(a.size-a.next) {
 		ptr := a.base + a.next
 		a.next += uint32(size)
@@ -282,12 +290,13 @@ func (a *arena) string(s string) uint32 {
 
 func exportCallbacks(env wazero.HostModuleBuilder) wazero.HostModuleBuilder {
 	util.ExportFuncII(env, "go_progress", progressCallback)
+	util.ExportFuncVIII(env, "go_log", logCallback)
 	util.ExportFuncVI(env, "go_destroy", destroyCallback)
-	util.ExportFuncVIII(env, "go_func", funcCallback)
-	util.ExportFuncVIII(env, "go_step", stepCallback)
-	util.ExportFuncVI(env, "go_final", finalCallback)
-	util.ExportFuncVI(env, "go_value", valueCallback)
-	util.ExportFuncVIII(env, "go_inverse", inverseCallback)
+	util.ExportFuncVIIII(env, "go_func", funcCallback)
+	util.ExportFuncVIIIII(env, "go_step", stepCallback)
+	util.ExportFuncVIII(env, "go_final", finalCallback)
+	util.ExportFuncVII(env, "go_value", valueCallback)
+	util.ExportFuncVIIII(env, "go_inverse", inverseCallback)
 	util.ExportFuncIIIIII(env, "go_compare", compareCallback)
 	util.ExportFuncIIIIII(env, "go_vtab_create", vtabModuleCallback(0))
 	util.ExportFuncIIIIII(env, "go_vtab_connect", vtabModuleCallback(1))

sqlite3/column.c

@@ -0,0 +1,51 @@
+#include <stddef.h>
+
+#include "sqlite3.h"
+
+union sqlite3_data {
+  sqlite3_int64 i;
+  double d;
+  struct {
+    const void *ptr;
+    int len;
+  };
+};
+
+int sqlite3_columns_go(sqlite3_stmt *stmt, int nCol, char *aType,
+                       union sqlite3_data *aData) {
+  if (nCol != sqlite3_column_count(stmt)) {
+    return SQLITE_MISUSE;
+  }
+  int rc = SQLITE_OK;
+  for (int i = 0; i < nCol; ++i) {
+    const void *ptr = NULL;
+    switch (aType[i] = sqlite3_column_type(stmt, i)) {
+      default:  // SQLITE_NULL
+        aData[i] = (union sqlite3_data){};
+      case SQLITE_INTEGER:
+        aData[i].i = sqlite3_column_int64(stmt, i);
+        continue;
+      case SQLITE_FLOAT:
+        aData[i].d = sqlite3_column_double(stmt, i);
+        continue;
+      case SQLITE_TEXT:
+        ptr = sqlite3_column_text(stmt, i);
+        break;
+      case SQLITE_BLOB:
+        ptr = sqlite3_column_blob(stmt, i);
+        break;
+    }
+    if (ptr == NULL && rc == SQLITE_OK) {
+      rc = sqlite3_errcode(sqlite3_db_handle(stmt));
+    }
+    aData[i].ptr = ptr;
+    aData[i].len = sqlite3_column_bytes(stmt, i);
+  }
+  return rc;
+}
+
+static_assert(offsetof(union sqlite3_data, i) == 0, "Unexpected offset");
+static_assert(offsetof(union sqlite3_data, d) == 0, "Unexpected offset");
+static_assert(offsetof(union sqlite3_data, ptr) == 0, "Unexpected offset");
+static_assert(offsetof(union sqlite3_data, len) == 4, "Unexpected offset");
+static_assert(sizeof(union sqlite3_data) == 8, "Unexpected size");

sqlite3/download.sh

@@ -3,7 +3,7 @@ set -euo pipefail
 
 cd -P -- "$(dirname -- "$0")"
 
-curl -#OL "https://sqlite.org/2023/sqlite-amalgamation-3440200.zip"
+curl -#OL "https://sqlite.org/2024/sqlite-amalgamation-3450000.zip"
 unzip -d . sqlite-amalgamation-*.zip
 mv sqlite-amalgamation-*/sqlite3* .
 rm -rf sqlite-amalgamation-*
@@ -12,24 +12,25 @@ cat *.patch | patch --no-backup-if-mismatch
 
 mkdir -p ext/
 cd ext/
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.44.2/ext/misc/decimal.c"
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.44.2/ext/misc/uint.c"
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.44.2/ext/misc/uuid.c"
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.44.2/ext/misc/base64.c"
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.44.2/ext/misc/regexp.c"
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.44.2/ext/misc/series.c"
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.44.2/ext/misc/anycollseq.c"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.0/ext/misc/anycollseq.c"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.0/ext/misc/base64.c"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.0/ext/misc/decimal.c"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.0/ext/misc/ieee754.c"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.0/ext/misc/regexp.c"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.0/ext/misc/series.c"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.0/ext/misc/uint.c"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.0/ext/misc/uuid.c"
 cd ~-
 
 cd ../vfs/tests/mptest/testdata/
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.44.2/mptest/mptest.c"
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.44.2/mptest/config01.test"
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.44.2/mptest/config02.test"
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.44.2/mptest/crash01.test"
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.44.2/mptest/crash02.subtest"
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.44.2/mptest/multiwrite01.test"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.0/mptest/mptest.c"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.0/mptest/config01.test"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.0/mptest/config02.test"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.0/mptest/crash01.test"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.0/mptest/crash02.subtest"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.0/mptest/multiwrite01.test"
 cd ~-
 
 cd ../vfs/tests/speedtest1/testdata/
-curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.44.2/test/speedtest1.c"
+curl -#OL "https://github.com/sqlite/sqlite/raw/version-3.45.0/test/speedtest1.c"
 cd ~-

sqlite3/func.c

@@ -3,14 +3,47 @@
 #include "include.h"
 #include "sqlite3.h"
 
-void go_func(sqlite3_context *, int, sqlite3_value **);
-void go_step(sqlite3_context *, int, sqlite3_value **);
-void go_final(sqlite3_context *);
-void go_value(sqlite3_context *);
-void go_inverse(sqlite3_context *, int, sqlite3_value **);
-
 int go_compare(go_handle, int, const void *, int, const void *);
 
+void go_func(sqlite3_context *, go_handle, int, sqlite3_value **);
+
+void go_step(sqlite3_context *, go_handle *, go_handle, int, sqlite3_value **);
+void go_final(sqlite3_context *, go_handle, go_handle);
+void go_value(sqlite3_context *, go_handle);
+void go_inverse(sqlite3_context *, go_handle *, int, sqlite3_value **);
+
+void go_func_wrapper(sqlite3_context *ctx, int nArg, sqlite3_value **pArg) {
+  go_func(ctx, sqlite3_user_data(ctx), nArg, pArg);
+}
+
+void go_step_wrapper(sqlite3_context *ctx, int nArg, sqlite3_value **pArg) {
+  go_handle *agg = sqlite3_aggregate_context(ctx, 4);
+  go_handle data = NULL;
+  if (agg == NULL || *agg == NULL) {
+    data = sqlite3_user_data(ctx);
+  }
+  go_step(ctx, agg, data, nArg, pArg);
+}
+
+void go_final_wrapper(sqlite3_context *ctx) {
+  go_handle *agg = sqlite3_aggregate_context(ctx, 0);
+  go_handle data = NULL;
+  if (agg == NULL || *agg == NULL) {
+    data = sqlite3_user_data(ctx);
+  }
+  go_final(ctx, agg, data);
+}
+
+void go_value_wrapper(sqlite3_context *ctx) {
+  go_handle *agg = sqlite3_aggregate_context(ctx, 4);
+  go_value(ctx, *agg);
+}
+
+void go_inverse_wrapper(sqlite3_context *ctx, int nArg, sqlite3_value **pArg) {
+  go_handle *agg = sqlite3_aggregate_context(ctx, 4);
+  go_inverse(ctx, *agg, nArg, pArg);
+}
+
 int sqlite3_create_collation_go(sqlite3 *db, const char *name, go_handle app) {
   int rc = sqlite3_create_collation_v2(db, name, SQLITE_UTF8, app, go_compare,
                                        go_destroy);
@@ -21,22 +54,22 @@ int sqlite3_create_collation_go(sqlite3 *db, const char *name, go_handle app) {
 int sqlite3_create_function_go(sqlite3 *db, const char *name, int argc,
                                int flags, go_handle app) {
   return sqlite3_create_function_v2(db, name, argc, SQLITE_UTF8 | flags, app,
-                                    go_func, /*step=*/NULL, /*final=*/NULL,
-                                    go_destroy);
+                                    go_func_wrapper, /*step=*/NULL,
+                                    /*final=*/NULL, go_destroy);
 }
 
 int sqlite3_create_aggregate_function_go(sqlite3 *db, const char *name,
                                          int argc, int flags, go_handle app) {
-  return sqlite3_create_window_function(db, name, argc, SQLITE_UTF8 | flags,
-                                        app, go_step, go_final, /*value=*/NULL,
-                                        /*inverse=*/NULL, go_destroy);
+  return sqlite3_create_function_v2(db, name, argc, SQLITE_UTF8 | flags, app,
+                                    /*func=*/NULL, go_step_wrapper,
+                                    go_final_wrapper, go_destroy);
 }
 
 int sqlite3_create_window_function_go(sqlite3 *db, const char *name, int argc,
                                       int flags, go_handle app) {
-  return sqlite3_create_window_function(db, name, argc, SQLITE_UTF8 | flags,
-                                        app, go_step, go_final, go_value,
-                                        go_inverse, go_destroy);
+  return sqlite3_create_window_function(
+      db, name, argc, SQLITE_UTF8 | flags, app, go_step_wrapper,
+      go_final_wrapper, go_value_wrapper, go_inverse_wrapper, go_destroy);
 }
 
 void sqlite3_set_auxdata_go(sqlite3_context *ctx, int i, go_handle aux) {

sqlite3/log.c

@@ -0,0 +1,9 @@
+#include <stdbool.h>
+
+#include "sqlite3.h"
+
+void go_log(void *, int, const char *);
+
+int sqlite3_config_log_go(bool enable) {
+  return sqlite3_config(SQLITE_CONFIG_LOG, enable ? go_log : NULL, NULL);
+}

sqlite3/main.c

@@ -4,12 +4,15 @@
 #include "ext/anycollseq.c"
 #include "ext/base64.c"
 #include "ext/decimal.c"
+#include "ext/ieee754.c"
 #include "ext/regexp.c"
 #include "ext/series.c"
 #include "ext/uint.c"
 #include "ext/uuid.c"
 // Bindings
+#include "column.c"
 #include "func.c"
+#include "log.c"
 #include "pointer.c"
 #include "progress.c"
 #include "time.c"
@@ -22,6 +25,7 @@ __attribute__((constructor)) void init() {
   sqlite3_initialize();
   sqlite3_auto_extension((void (*)(void))sqlite3_base_init);
   sqlite3_auto_extension((void (*)(void))sqlite3_decimal_init);
+  sqlite3_auto_extension((void (*)(void))sqlite3_ieee_init);
   sqlite3_auto_extension((void (*)(void))sqlite3_regexp_init);
   sqlite3_auto_extension((void (*)(void))sqlite3_series_init);
   sqlite3_auto_extension((void (*)(void))sqlite3_uint_init);

sqlite3/vfs.c

@@ -67,7 +67,7 @@ int sqlite3_os_init() {
   static sqlite3_vfs os_vfs = {
       .iVersion = 2,
       .szOsFile = sizeof(struct go_file),
-      .mxPathname = 512,
+      .mxPathname = 1024,
       .zName = "os",
 
       .xOpen = go_open_wrapper,
@@ -113,7 +113,7 @@ sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName) {
     *go_vfs_list = (sqlite3_vfs){
         .iVersion = 2,
         .szOsFile = sizeof(struct go_file),
-        .mxPathname = 512,
+        .mxPathname = 1024,
         .zName = name,
         .pNext = head,
 

sqlite3/vtab.c

@@ -136,12 +136,10 @@ static int go_cur_close_wrapper(sqlite3_vtab_cursor *pCursor) {
 static int go_vtab_find_function_wrapper(
     sqlite3_vtab *pVTab, int nArg, const char *zName,
     void (**pxFunc)(sqlite3_context *, int, sqlite3_value **), void **ppArg) {
-  struct go_vtab *vtab = container_of(pVTab, struct go_vtab, base);
-
   go_handle handle;
   int rc = go_vtab_find_function(pVTab, nArg, zName, &handle);
   if (rc) {
-    *pxFunc = go_func;
+    *pxFunc = go_func_wrapper;
     *ppArg = handle;
   }
   return rc;

stmt.go

@@ -340,7 +340,7 @@ func (s *Stmt) BindJSON(param int, value any) error {
 //
 // https://sqlite.org/c3ref/bind_blob.html
 func (s *Stmt) BindValue(param int, value Value) error {
-	if value.sqlite != s.c.sqlite {
+	if value.c != s.c {
 		return MISUSE
 	}
 	r := s.c.call("sqlite3_bind_value",
@@ -403,10 +403,7 @@ func (s *Stmt) ColumnDeclType(col int) string {
 //
 // https://sqlite.org/c3ref/column_blob.html
 func (s *Stmt) ColumnBool(col int) bool {
-	if i := s.ColumnInt64(col); i != 0 {
-		return true
-	}
-	return false
+	return s.ColumnInt64(col) != 0
 }
 
 // ColumnInt returns the value of the result column as an int.
@@ -547,8 +544,45 @@ func (s *Stmt) ColumnValue(col int) Value {
 	r := s.c.call("sqlite3_column_value",
 		uint64(s.handle), uint64(col))
 	return Value{
+		c:      s.c,
 		unprot: true,
-		sqlite: s.c.sqlite,
 		handle: uint32(r),
 	}
 }
+
+func (s *Stmt) Columns(dest []any) error {
+	defer s.c.arena.mark()()
+	count := uint64(len(dest))
+	typePtr := s.c.arena.new(count)
+	dataPtr := s.c.arena.new(8 * count)
+
+	r := s.c.call("sqlite3_columns_go",
+		uint64(s.handle), count, uint64(typePtr), uint64(dataPtr))
+	if err := s.c.error(r); err != nil {
+		return err
+	}
+
+	types := util.View(s.c.mod, typePtr, count)
+	for i := range dest {
+		switch types[i] {
+		case byte(INTEGER):
+			dest[i] = int64(util.ReadUint64(s.c.mod, dataPtr+8*uint32(i)))
+			continue
+		case byte(FLOAT):
+			dest[i] = util.ReadFloat64(s.c.mod, dataPtr+8*uint32(i))
+			continue
+		case byte(NULL):
+			dest[i] = nil
+			continue
+		}
+		ptr := util.ReadUint32(s.c.mod, dataPtr+8*uint32(i)+0)
+		len := util.ReadUint32(s.c.mod, dataPtr+8*uint32(i)+4)
+		buf := util.View(s.c.mod, ptr, uint64(len))
+		if types[i] == byte(TEXT) {
+			dest[i] = string(buf)
+		} else {
+			dest[i] = buf
+		}
+	}
+	return nil
+}

tests/conn_test.go

@@ -289,3 +289,78 @@ func TestConn_Prepare_invalid(t *testing.T) {
 		t.Error("got message:", got)
 	}
 }
+
+func TestConn_Config(t *testing.T) {
+	t.Parallel()
+
+	db, err := sqlite3.Open(":memory:")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+
+	o, err := db.Config(sqlite3.DBCONFIG_DEFENSIVE)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if o != false {
+		t.Error("want false")
+	}
+
+	o, err = db.Config(sqlite3.DBCONFIG_DEFENSIVE, true)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if o != true {
+		t.Error("want true")
+	}
+
+	o, err = db.Config(sqlite3.DBCONFIG_DEFENSIVE)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if o != true {
+		t.Error("want true")
+	}
+
+	o, err = db.Config(sqlite3.DBCONFIG_DEFENSIVE, false)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if o != false {
+		t.Error("want false")
+	}
+
+	o, err = db.Config(sqlite3.DBCONFIG_DEFENSIVE)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if o != false {
+		t.Error("want false")
+	}
+}
+
+func TestConn_ConfigLog(t *testing.T) {
+	t.Parallel()
+
+	db, err := sqlite3.Open(":memory:")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+
+	var code sqlite3.ExtendedErrorCode
+	err = db.ConfigLog(func(c sqlite3.ExtendedErrorCode, msg string) {
+		t.Log(msg)
+		code = c
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	db.Prepare(`SELECT * FRM sqlite_schema`)
+
+	if code != sqlite3.ExtendedErrorCode(sqlite3.ERROR) {
+		t.Error("want sqlite3.ERROR")
+	}
+}

tests/func_test.go

@@ -167,6 +167,26 @@ func TestCreateFunction(t *testing.T) {
 	}
 }
 
+func TestOverloadFunction(t *testing.T) {
+	t.Parallel()
+
+	db, err := sqlite3.Open(":memory:")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+
+	err = db.OverloadFunction("test", 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = db.Exec(`SELECT test()`)
+	if err == nil {
+		t.Fatal("want error")
+	}
+}
+
 func TestAnyCollationNeeded(t *testing.T) {
 	t.Parallel()
 

time.go

@@ -344,7 +344,11 @@ type timeScanner struct {
 	TimeFormat
 }
 
-func (s timeScanner) Scan(src any) (err error) {
-	*s.Time, err = s.Decode(src)
-	return
+func (s timeScanner) Scan(src any) error {
+	var ok bool
+	var err error
+	if *s.Time, ok = src.(time.Time); !ok {
+		*s.Time, err = s.Decode(src)
+	}
+	return err
 }

util/fsutil/mode.go

@@ -0,0 +1,95 @@
+package fsutil
+
+import (
+	"io/fs"
+
+	"github.com/ncruces/go-sqlite3"
+	"github.com/ncruces/go-sqlite3/internal/util"
+)
+
+// ParseFileMode parses a file mode as returned by
+// [fs.FileMode.String].
+func ParseFileMode(str string) (fs.FileMode, error) {
+	var mode fs.FileMode
+	err := util.ErrorString("invalid mode: " + str)
+
+	if len(str) < 10 {
+		return 0, err
+	}
+
+	for i, c := range []byte("dalTLDpSugct?") {
+		if str[0] == c {
+			if len(str) < 10 {
+				return 0, err
+			}
+			mode |= 1 << uint(32-1-i)
+			str = str[1:]
+		}
+	}
+
+	if mode == 0 {
+		if str[0] != '-' {
+			return 0, err
+		}
+		str = str[1:]
+	}
+	if len(str) != 9 {
+		return 0, err
+	}
+
+	for i, c := range []byte("rwxrwxrwx") {
+		if str[i] == c {
+			mode |= 1 << uint(9-1-i)
+		}
+		if str[i] != '-' {
+			return 0, err
+		}
+	}
+
+	return mode, nil
+}
+
+// FileModeFromUnix converts a POSIX mode_t to a file mode.
+func FileModeFromUnix(mode fs.FileMode) fs.FileMode {
+	const (
+		S_IFMT   fs.FileMode = 0170000
+		S_IFIFO  fs.FileMode = 0010000
+		S_IFCHR  fs.FileMode = 0020000
+		S_IFDIR  fs.FileMode = 0040000
+		S_IFBLK  fs.FileMode = 0060000
+		S_IFREG  fs.FileMode = 0100000
+		S_IFLNK  fs.FileMode = 0120000
+		S_IFSOCK fs.FileMode = 0140000
+	)
+
+	switch mode & S_IFMT {
+	case S_IFDIR:
+		mode |= fs.ModeDir
+	case S_IFLNK:
+		mode |= fs.ModeSymlink
+	case S_IFBLK:
+		mode |= fs.ModeDevice
+	case S_IFCHR:
+		mode |= fs.ModeCharDevice | fs.ModeDevice
+	case S_IFIFO:
+		mode |= fs.ModeNamedPipe
+	case S_IFSOCK:
+		mode |= fs.ModeSocket
+	case S_IFREG, 0:
+		//
+	default:
+		mode |= fs.ModeIrregular
+	}
+
+	return mode &^ S_IFMT
+}
+
+// FileModeFromValue calls [FileModeFromUnix] for numeric values,
+// and [ParseFileMode] for textual values.
+func FileModeFromValue(val sqlite3.Value) fs.FileMode {
+	if n := val.Int64(); n != 0 {
+		return FileModeFromUnix(fs.FileMode(n))
+	}
+	mode, _ := ParseFileMode(val.Text())
+	return mode
+}

util/fsutil/mode_test.go

@@ -0,0 +1,54 @@
+package fsutil
+
+import (
+	"io/fs"
+	"testing"
+)
+
+func TestFileModeFromUnix(t *testing.T) {
+	tests := []struct {
+		mode fs.FileMode
+		want fs.FileMode
+	}{
+		{0010754, 0754 | fs.ModeNamedPipe},
+		{0020754, 0754 | fs.ModeCharDevice | fs.ModeDevice},
+		{0040754, 0754 | fs.ModeDir},
+		{0060754, 0754 | fs.ModeDevice},
+		{0100754, 0754},
+		{0120754, 0754 | fs.ModeSymlink},
+		{0140754, 0754 | fs.ModeSocket},
+		{0170754, 0754 | fs.ModeIrregular},
+	}
+	for _, tt := range tests {
+		t.Run(tt.mode.String(), func(t *testing.T) {
+			if got := FileModeFromUnix(tt.mode); got != tt.want {
+				t.Errorf("fixMode() = %o, want %o", got, tt.want)
+			}
+		})
+	}
+}
+
+func FuzzParseFileMode(f *testing.F) {
+	f.Add("---------")
+	f.Add("rwxrwxrwx")
+	f.Add("----------")
+	f.Add("-rwxrwxrwx")
+	f.Add("b")
+	f.Add("b---------")
+	f.Add("drwxrwxrwx")
+	f.Add("dalTLDpSugct?")
+	f.Add("dalTLDpSugct?---------")
+	f.Add("dalTLDpSugct?rwxrwxrwx")
+	f.Add("dalTLDpSugct?----------")
+
+	f.Fuzz(func(t *testing.T, str string) {
+		mode, err := ParseFileMode(str)
+		if err != nil {
+			return
+		}
+		got := mode.String()
+		if got != str {
+			t.Errorf("was %q, got %q (%o)", str, got, mode)
+		}
+	})
+}

util/ioutil/ioutil.go

@@ -0,0 +1,2 @@
+// Package ioutil implements I/O utility functions.
+package ioutil

util/ioutil/seek.go

@@ -0,0 +1,60 @@
+package ioutil
+
+import (
+	"io"
+	"sync"
+)
+
+// SeekingReaderAt implements [io.ReaderAt]
+// through an underlying [io.ReadSeeker].
+type SeekingReaderAt struct {
+	l sync.Mutex
+	r io.ReadSeeker
+}
+
+// NewSeekingReaderAt creates a new SeekingReaderAt.
+// The SeekingReaderAt takes ownership of r
+// and will modify its seek offset,
+// so callers should not use r after this call.
+func NewSeekingReaderAt(r io.ReadSeeker) *SeekingReaderAt {
+	return &SeekingReaderAt{r: r}
+}
+
+// ReadAt implements [io.ReaderAt].
+func (s *SeekingReaderAt) ReadAt(p []byte, off int64) (n int, _ error) {
+	s.l.Lock()
+	defer s.l.Unlock()
+
+	_, err := s.r.Seek(off, io.SeekStart)
+	if err != nil {
+		return 0, err
+	}
+
+	for len(p) > 0 {
+		i, err := s.r.Read(p)
+		p = p[i:]
+		n += i
+		if err != nil {
+			return n, err
+		}
+	}
+	return n, nil
+}
+
+// Size implements [SizeReaderAt].
+func (s *SeekingReaderAt) Size() (int64, error) {
+	s.l.Lock()
+	defer s.l.Unlock()
+	return s.r.Seek(0, io.SeekEnd)
+}
+
+// ReadAt implements [io.Closer].
+func (s *SeekingReaderAt) Close() error {
+	s.l.Lock()
+	defer s.l.Unlock()
+	if c, ok := s.r.(io.Closer); ok {
+		s.r = nil
+		return c.Close()
+	}
+	return nil
+}

util/ioutil/seek_test.go

@@ -0,0 +1,28 @@
+package ioutil
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestNewSeekingReaderAt(t *testing.T) {
+	reader := NewSeekingReaderAt(strings.NewReader("abc"))
+	defer reader.Close()
+
+	n, err := reader.Size()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if n != 3 {
+		t.Errorf("got %d", n)
+	}
+
+	var buf [3]byte
+	r, err := reader.ReadAt(buf[:], 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if r != 3 {
+		t.Errorf("got %d", r)
+	}
+}

util/ioutil/size.go

@@ -0,0 +1,48 @@
+package ioutil
+
+import (
+	"io"
+	"io/fs"
+
+	"github.com/ncruces/go-sqlite3"
+)
+
+// A SizeReaderAt is a ReaderAt with a Size method.
+// Use [NewSizeReaderAt] to adapt different Size interfaces.
+type SizeReaderAt interface {
+	Size() (int64, error)
+	io.ReaderAt
+}
+
+// NewSizeReaderAt returns a SizeReaderAt given an io.ReaderAt
+// that implements one of:
+//   - Size() (int64, error)
+//   - Size() int64
+//   - Len() int
+//   - Stat() (fs.FileInfo, error)
+//   - Seek(offset int64, whence int) (int64, error)
+func NewSizeReaderAt(r io.ReaderAt) SizeReaderAt {
+	return sizer{r}
+}
+
+type sizer struct{ io.ReaderAt }
+
+func (s sizer) Size() (int64, error) {
+	switch s := s.ReaderAt.(type) {
+	case interface{ Size() (int64, error) }:
+		return s.Size()
+	case interface{ Size() int64 }:
+		return s.Size(), nil
+	case interface{ Len() int }:
+		return int64(s.Len()), nil
+	case interface{ Stat() (fs.FileInfo, error) }:
+		fi, err := s.Stat()
+		if err != nil {
+			return 0, err
+		}
+		return fi.Size(), nil
+	case io.Seeker:
+		return s.Seek(0, io.SeekEnd)
+	}
+	return 0, sqlite3.IOERR_SEEK
+}

util/ioutil/size_test.go

@@ -1,4 +1,4 @@
-package readervfs
+package ioutil
 
 import (
 	"io"

util/osutil/open.go

@@ -0,0 +1,16 @@
+//go:build !windows
+
+package osutil
+
+import (
+	"io/fs"
+	"os"
+)
+
+// OpenFile behaves the same as [os.OpenFile],
+// except on Windows it sets [syscall.FILE_SHARE_DELETE].
+//
+// See: https://go.dev/issue/32088#issuecomment-502850674
+func OpenFile(name string, flag int, perm fs.FileMode) (*os.File, error) {
+	return os.OpenFile(name, flag, perm)
+}

util/osutil/open_windows.go

@@ -0,0 +1,108 @@
+package osutil
+
+import (
+	"io/fs"
+	"os"
+	. "syscall"
+	"unsafe"
+)
+
+// OpenFile behaves the same as [os.OpenFile],
+// except on Windows it sets [syscall.FILE_SHARE_DELETE].
+//
+// See: https://go.dev/issue/32088#issuecomment-502850674
+func OpenFile(name string, flag int, perm fs.FileMode) (*os.File, error) {
+	if name == "" {
+		return nil, &os.PathError{Op: "open", Path: name, Err: 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
+}
+
+// syscallOpen is a 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 Handle, err error) {
+	if len(path) == 0 {
+		return InvalidHandle, ERROR_FILE_NOT_FOUND
+	}
+	pathp, err := UTF16PtrFromString(path)
+	if err != nil {
+		return InvalidHandle, err
+	}
+	var access uint32
+	switch mode & (O_RDONLY | O_WRONLY | O_RDWR) {
+	case O_RDONLY:
+		access = GENERIC_READ
+	case O_WRONLY:
+		access = GENERIC_WRITE
+	case O_RDWR:
+		access = GENERIC_READ | GENERIC_WRITE
+	}
+	if mode&O_CREAT != 0 {
+		access |= GENERIC_WRITE
+	}
+	if mode&O_APPEND != 0 {
+		access &^= GENERIC_WRITE
+		access |= FILE_APPEND_DATA
+	}
+	sharemode := uint32(FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE)
+	var sa *SecurityAttributes
+	if mode&O_CLOEXEC == 0 {
+		sa = makeInheritSa()
+	}
+	var createmode uint32
+	switch {
+	case mode&(O_CREAT|O_EXCL) == (O_CREAT | O_EXCL):
+		createmode = CREATE_NEW
+	case mode&(O_CREAT|O_TRUNC) == (O_CREAT | O_TRUNC):
+		createmode = CREATE_ALWAYS
+	case mode&O_CREAT == O_CREAT:
+		createmode = OPEN_ALWAYS
+	case mode&O_TRUNC == O_TRUNC:
+		createmode = TRUNCATE_EXISTING
+	default:
+		createmode = OPEN_EXISTING
+	}
+	var attrs uint32 = FILE_ATTRIBUTE_NORMAL
+	if perm&S_IWRITE == 0 {
+		attrs = FILE_ATTRIBUTE_READONLY
+		if createmode == CREATE_ALWAYS {
+			const _ERROR_BAD_NETPATH = Errno(53)
+			// We have been asked to create a read-only file.
+			// If the file already exists, the semantics of
+			// the Unix open system call is to preserve the
+			// existing permissions. If we pass CREATE_ALWAYS
+			// and FILE_ATTRIBUTE_READONLY to CreateFile,
+			// and the file already exists, CreateFile will
+			// change the file permissions.
+			// Avoid that to preserve the Unix semantics.
+			h, e := CreateFile(pathp, access, sharemode, sa, TRUNCATE_EXISTING, FILE_ATTRIBUTE_NORMAL, 0)
+			switch e {
+			case ERROR_FILE_NOT_FOUND, _ERROR_BAD_NETPATH, ERROR_PATH_NOT_FOUND:
+				// File does not exist. These are the same
+				// errors as Errno.Is checks for ErrNotExist.
+				// Carry on to create the file.
+			default:
+				// Success or some different error.
+				return h, e
+			}
+		}
+	}
+	if createmode == OPEN_EXISTING && access == GENERIC_READ {
+		// Necessary for opening directory handles.
+		attrs |= FILE_FLAG_BACKUP_SEMANTICS
+	}
+	return CreateFile(pathp, access, sharemode, sa, createmode, attrs, 0)
+}
+
+func makeInheritSa() *SecurityAttributes {
+	var sa SecurityAttributes
+	sa.Length = uint32(unsafe.Sizeof(sa))
+	sa.InheritHandle = 1
+	return &sa
+}

util/osutil/osfs.go

@@ -0,0 +1,33 @@
+package osutil
+
+import (
+	"io/fs"
+	"os"
+)
+
+// FS implements [fs.FS], [fs.StatFS], and [fs.ReadFileFS]
+// using package [os].
+//
+// This filesystem does not respect [fs.ValidPath] rules,
+// and fails [testing/fstest.TestFS]!
+//
+// Still, it can be a useful tool to unify implementations
+// that can access either the [os] filesystem or an [fs.FS].
+// It's OK to use this to open files, but you should avoid
+// opening directories, resolving paths, or walking the file system.
+type FS struct{}
+
+// Open implements [fs.FS].
+func (FS) Open(name string) (fs.File, error) {
+	return OpenFile(name, os.O_RDONLY, 0)
+}
+
+// ReadFileFS implements [fs.StatFS].
+func (FS) Stat(name string) (fs.FileInfo, error) {
+	return os.Stat(name)
+}
+
+// ReadFile implements [fs.ReadFileFS].
+func (FS) ReadFile(name string) ([]byte, error) {
+	return os.ReadFile(name)
+}

util/osutil/osutil.go

@@ -0,0 +1,2 @@
+// Package osutil implements operating system utility functions.
+package osutil

util/vtabutil/arg.go

@@ -0,0 +1,34 @@
+// Package ioutil implements virtual table utility functions.
+package vtabutil
+
+import "strings"
+
+// NamedArg splits an named arg into a key and value,
+// around an equals sign.
+// Spaces are trimmed around both key and value.
+func NamedArg(arg string) (key, val string) {
+	key, val, _ = strings.Cut(arg, "=")
+	key = strings.TrimSpace(key)
+	val = strings.TrimSpace(val)
+	return
+}
+
+// Unquote unquotes a string.
+func Unquote(val string) string {
+	if len(val) < 2 {
+		return val
+	}
+	if val[0] != val[len(val)-1] {
+		return val
+	}
+	var old, new string
+	switch val[0] {
+	default:
+		return val
+	case '"':
+		old, new = `""`, `"`
+	case '\'':
+		old, new = `''`, `'`
+	}
+	return strings.ReplaceAll(val[1:len(val)-1], old, new)
+}

value.go

@@ -13,7 +13,7 @@ import (
 //
 // https://sqlite.org/c3ref/value.html
 type Value struct {
-	*sqlite
+	c      *Conn
 	handle uint32
 	unprot bool
 	copied bool
@@ -30,10 +30,10 @@ func (v Value) protected() uint64 {
 //
 // https://sqlite.org/c3ref/value_dup.html
 func (v Value) Dup() *Value {
-	r := v.call("sqlite3_value_dup", uint64(v.handle))
+	r := v.c.call("sqlite3_value_dup", uint64(v.handle))
 	return &Value{
+		c:      v.c,
 		copied: true,
-		sqlite: v.sqlite,
 		handle: uint32(r),
 	}
 }
@@ -45,16 +45,24 @@ func (dup *Value) Close() error {
 	if !dup.copied {
 		panic(util.ValueErr)
 	}
-	dup.call("sqlite3_value_free", uint64(dup.handle))
+	dup.c.call("sqlite3_value_free", uint64(dup.handle))
 	dup.handle = 0
 	return nil
 }
 
-// Type returns the initial [Datatype] of the value.
+// Type returns the initial datatype of the value.
 //
 // https://sqlite.org/c3ref/value_blob.html
 func (v Value) Type() Datatype {
-	r := v.call("sqlite3_value_type", v.protected())
+	r := v.c.call("sqlite3_value_type", v.protected())
+	return Datatype(r)
+}
+
+// Type returns the numeric datatype of the value.
+//
+// https://sqlite.org/c3ref/value_blob.html
+func (v Value) NumericType() Datatype {
+	r := v.c.call("sqlite3_value_numeric_type", v.protected())
 	return Datatype(r)
 }
 
@@ -65,10 +73,7 @@ func (v Value) Type() Datatype {
 //
 // https://sqlite.org/c3ref/value_blob.html
 func (v Value) Bool() bool {
-	if i := v.Int64(); i != 0 {
-		return true
-	}
-	return false
+	return v.Int64() != 0
 }
 
 // Int returns the value as an int.
@@ -82,7 +87,7 @@ func (v Value) Int() int {
 //
 // https://sqlite.org/c3ref/value_blob.html
 func (v Value) Int64() int64 {
-	r := v.call("sqlite3_value_int64", v.protected())
+	r := v.c.call("sqlite3_value_int64", v.protected())
 	return int64(r)
 }
 
@@ -90,7 +95,7 @@ func (v Value) Int64() int64 {
 //
 // https://sqlite.org/c3ref/value_blob.html
 func (v Value) Float() float64 {
-	r := v.call("sqlite3_value_double", v.protected())
+	r := v.c.call("sqlite3_value_double", v.protected())
 	return math.Float64frombits(r)
 }
 
@@ -136,7 +141,7 @@ func (v Value) Blob(buf []byte) []byte {
 //
 // https://sqlite.org/c3ref/value_blob.html
 func (v Value) RawText() []byte {
-	r := v.call("sqlite3_value_text", v.protected())
+	r := v.c.call("sqlite3_value_text", v.protected())
 	return v.rawBytes(uint32(r))
 }
 
@@ -146,7 +151,7 @@ func (v Value) RawText() []byte {
 //
 // https://sqlite.org/c3ref/value_blob.html
 func (v Value) RawBlob() []byte {
-	r := v.call("sqlite3_value_blob", v.protected())
+	r := v.c.call("sqlite3_value_blob", v.protected())
 	return v.rawBytes(uint32(r))
 }
 
@@ -155,15 +160,15 @@ func (v Value) rawBytes(ptr uint32) []byte {
 		return nil
 	}
 
-	r := v.call("sqlite3_value_bytes", v.protected())
-	return util.View(v.mod, ptr, r)
+	r := v.c.call("sqlite3_value_bytes", v.protected())
+	return util.View(v.c.mod, ptr, r)
 }
 
 // Pointer gets the pointer associated with this value,
 // or nil if it has no associated pointer.
 func (v Value) Pointer() any {
-	r := v.call("sqlite3_value_pointer_go", v.protected())
-	return util.GetHandle(v.ctx, uint32(r))
+	r := v.c.call("sqlite3_value_pointer_go", v.protected())
+	return util.GetHandle(v.c.ctx, uint32(r))
 }
 
 // JSON parses a JSON-encoded value
@@ -186,3 +191,46 @@ func (v Value) JSON(ptr any) error {
 	}
 	return json.Unmarshal(data, ptr)
 }
+
+// NoChange returns true if and only if the value is unchanged
+// in a virtual table update operatiom.
+//
+// https://sqlite.org/c3ref/value_blob.html
+func (v Value) NoChange() bool {
+	r := v.c.call("sqlite3_value_nochange", v.protected())
+	return r != 0
+}
+
+// InFirst returns the first element
+// on the right-hand side of an IN constraint.
+//
+// https://www.sqlite.org/c3ref/vtab_in_first.html
+func (v Value) InFirst() (Value, error) {
+	defer v.c.arena.mark()()
+	valPtr := v.c.arena.new(ptrlen)
+	r := v.c.call("sqlite3_vtab_in_first", uint64(v.handle), uint64(valPtr))
+	if err := v.c.error(r); err != nil {
+		return Value{}, err
+	}
+	return Value{
+		c:      v.c,
+		handle: util.ReadUint32(v.c.mod, valPtr),
+	}, nil
+}
+
+// InNext returns the next element
+// on the right-hand side of an IN constraint.
+//
+// https://www.sqlite.org/c3ref/vtab_in_first.html
+func (v Value) InNext() (Value, error) {
+	defer v.c.arena.mark()()
+	valPtr := v.c.arena.new(ptrlen)
+	r := v.c.call("sqlite3_vtab_in_next", uint64(v.handle), uint64(valPtr))
+	if err := v.c.error(r); err != nil {
+		return Value{}, err
+	}
+	return Value{
+		c:      v.c,
+		handle: util.ReadUint32(v.c.mod, valPtr),
+	}, nil
+}

vfs/const.go

@@ -3,8 +3,8 @@ package vfs
 import "github.com/ncruces/go-sqlite3/internal/util"
 
 const (
-	_MAX_NAME            = 512 // Used for short strings: names, error messages…
-	_MAX_PATHNAME        = 512
+	_MAX_NAME            = 1e6 // Self-imposed limit for most NUL terminated strings.
+	_MAX_PATHNAME        = 1024
 	_DEFAULT_SECTOR_SIZE = 4096
 )
 

vfs/file.go

@@ -9,6 +9,8 @@ import (
 	"path/filepath"
 	"runtime"
 	"syscall"
+
+	"github.com/ncruces/go-sqlite3/util/osutil"
 )
 
 type vfsOS struct{}
@@ -91,7 +93,7 @@ func (vfsOS) OpenParams(name string, flags OpenFlag, params url.Values) (File, O
 	if name == "" {
 		f, err = os.CreateTemp("", "*.db")
 	} else {
-		f, err = osOpenFile(name, oflags, 0666)
+		f, err = osutil.OpenFile(name, oflags, 0666)
 	}
 	if err != nil {
 		if errors.Is(err, syscall.EISDIR) {

vfs/os_std_open.go

@@ -1,12 +0,0 @@
-//go:build !windows || sqlite3_nosys
-
-package vfs
-
-import (
-	"io/fs"
-	"os"
-)
-
-func osOpenFile(name string, flag int, perm fs.FileMode) (*os.File, error) {
-	return os.OpenFile(name, flag, perm)
-}

vfs/os_windows.go

@@ -3,30 +3,12 @@
 package vfs
 
 import (
-	"io/fs"
 	"os"
-	"syscall"
 	"time"
 
 	"golang.org/x/sys/windows"
 )
 
-// osOpenFile 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 osOpenFile(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 osGetSharedLock(file *os.File) _ErrorCode {
 	// Acquire the PENDING lock temporarily before acquiring a new SHARED lock.
 	rc := osReadLock(file, _PENDING_BYTE, 1, 0)
@@ -183,55 +165,3 @@ func osLockErrorCode(err error, def _ErrorCode) _ErrorCode {
 	}
 	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)
-}

vfs/readervfs/api.go

@@ -9,11 +9,9 @@
 package readervfs
 
 import (
-	"io"
-	"io/fs"
 	"sync"
 
-	"github.com/ncruces/go-sqlite3"
+	"github.com/ncruces/go-sqlite3/util/ioutil"
 	"github.com/ncruces/go-sqlite3/vfs"
 )
 
@@ -24,13 +22,13 @@ func init() {
 var (
 	readerMtx sync.RWMutex
 	// +checklocks:readerMtx
-	readerDBs = map[string]SizeReaderAt{}
+	readerDBs = map[string]ioutil.SizeReaderAt{}
 )
 
 // Create creates an immutable database from reader.
 // The caller should ensure that data from reader does not mutate,
 // otherwise SQLite might return incorrect query results and/or [sqlite3.CORRUPT] errors.
-func Create(name string, reader SizeReaderAt) {
+func Create(name string, reader ioutil.SizeReaderAt) {
 	readerMtx.Lock()
 	defer readerMtx.Unlock()
 	readerDBs[name] = reader
@@ -42,43 +40,3 @@ func Delete(name string) {
 	defer readerMtx.Unlock()
 	delete(readerDBs, name)
 }
-
-// A SizeReaderAt is a ReaderAt with a Size method.
-// Use [NewSizeReaderAt] to adapt different Size interfaces.
-type SizeReaderAt interface {
-	Size() (int64, error)
-	io.ReaderAt
-}
-
-// NewSizeReaderAt returns a SizeReaderAt given an io.ReaderAt
-// that implements one of:
-//   - Size() (int64, error)
-//   - Size() int64
-//   - Len() int
-//   - Stat() (fs.FileInfo, error)
-//   - Seek(offset int64, whence int) (int64, error)
-func NewSizeReaderAt(r io.ReaderAt) SizeReaderAt {
-	return sizer{r}
-}
-
-type sizer struct{ io.ReaderAt }
-
-func (s sizer) Size() (int64, error) {
-	switch s := s.ReaderAt.(type) {
-	case interface{ Size() (int64, error) }:
-		return s.Size()
-	case interface{ Size() int64 }:
-		return s.Size(), nil
-	case interface{ Len() int }:
-		return int64(s.Len()), nil
-	case interface{ Stat() (fs.FileInfo, error) }:
-		fi, err := s.Stat()
-		if err != nil {
-			return 0, err
-		}
-		return fi.Size(), nil
-	case io.Seeker:
-		return s.Seek(0, io.SeekEnd)
-	}
-	return 0, sqlite3.IOERR_SEEK
-}

vfs/readervfs/example_test.go

@@ -10,6 +10,7 @@ import (
 
 	_ "github.com/ncruces/go-sqlite3/driver"
 	_ "github.com/ncruces/go-sqlite3/embed"
+	"github.com/ncruces/go-sqlite3/util/ioutil"
 	"github.com/ncruces/go-sqlite3/vfs/readervfs"
 	"github.com/psanford/httpreadat"
 )
@@ -65,7 +66,7 @@ func Example_http() {
 }
 
 func Example_embed() {
-	readervfs.Create("test.db", readervfs.NewSizeReaderAt(strings.NewReader(testDB)))
+	readervfs.Create("test.db", ioutil.NewSizeReaderAt(strings.NewReader(testDB)))
 	defer readervfs.Delete("test.db")
 
 	db, err := sql.Open("sqlite3", "file:test.db?vfs=reader")

vfs/readervfs/reader.go

@@ -2,6 +2,7 @@ package readervfs
 
 import (
 	"github.com/ncruces/go-sqlite3"
+	"github.com/ncruces/go-sqlite3/util/ioutil"
 	"github.com/ncruces/go-sqlite3/vfs"
 )
 
@@ -31,7 +32,7 @@ func (readerVFS) FullPathname(name string) (string, error) {
 	return name, nil
 }
 
-type readerFile struct{ SizeReaderAt }
+type readerFile struct{ ioutil.SizeReaderAt }
 
 func (readerFile) Close() error {
 	return nil

vfs/tests/mptest/testdata/build.sh

@@ -7,7 +7,7 @@ ROOT=../../../../
 BINARYEN="$ROOT/tools/binaryen-version_116/bin"
 WASI_SDK="$ROOT/tools/wasi-sdk-21.0/bin"
 
-"$WASI_SDK/clang" --target=wasm32-wasi -flto -g0 -O2 \
+"$WASI_SDK/clang" --target=wasm32-wasi -std=c17 -flto -g0 -O2 \
   -o mptest.wasm main.c \
 	-I"$ROOT/sqlite3" \
 	-msimd128 -mmutable-globals \

vfs/tests/mptest/testdata/mptest.wasm.bz2

@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:91dade19dcd4509f47cb09f16af0cdf7eb2b09cef0e43a0e1ee380629a8c9778
-size 512403
+oid sha256:bb763a5cc1c10683441f34ea64253eefc5b7b2d7208f9db6632c5b64da9a50a7
+size 520353

vfs/tests/speedtest1/testdata/build.sh

@@ -7,7 +7,7 @@ ROOT=../../../../
 BINARYEN="$ROOT/tools/binaryen-version_116/bin"
 WASI_SDK="$ROOT/tools/wasi-sdk-21.0/bin"
 
-"$WASI_SDK/clang" --target=wasm32-wasi -flto -g0 -O2 \
+"$WASI_SDK/clang" --target=wasm32-wasi -std=c17 -flto -g0 -O2 \
 	-o speedtest1.wasm main.c \
 	-I"$ROOT/sqlite3" \
 	-msimd128 -mmutable-globals \

vfs/tests/speedtest1/testdata/speedtest1.wasm.bz2

@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:ff3c4ed5a8579206a2e48c4f8e72f483288f8b113b4664e92cb308a977556a42
-size 526453
+oid sha256:a2d0b8b5d044cd993ccec28f3c491d862971d0e2e6ac78d6aa757d252ab63a4b
+size 534561

vtab.go

@@ -66,32 +66,53 @@ func implements[T any](typ reflect.Type) bool {
 	return typ.Implements(reflect.TypeOf(ptr).Elem())
 }
 
-// DeclareVtab declares the schema of a virtual table.
+// DeclareVTab declares the schema of a virtual table.
 //
 // https://sqlite.org/c3ref/declare_vtab.html
-func (c *Conn) DeclareVtab(sql string) error {
+func (c *Conn) DeclareVTab(sql string) error {
 	defer c.arena.mark()()
 	sqlPtr := c.arena.string(sql)
 	r := c.call("sqlite3_declare_vtab", uint64(c.handle), uint64(sqlPtr))
 	return c.error(r)
 }
 
-// IndexConstraintOp is a virtual table constraint operator code.
+// VTabConflictMode is a virtual table conflict resolution mode.
 //
-// https://sqlite.org/c3ref/c_vtab_constraint_support.html
-type VtabConfigOption uint8
+// https://www.sqlite.org/c3ref/c_fail.html
+type VTabConflictMode uint8
 
 const (
-	VTAB_CONSTRAINT_SUPPORT VtabConfigOption = 1
-	VTAB_INNOCUOUS          VtabConfigOption = 2
-	VTAB_DIRECTONLY         VtabConfigOption = 3
-	VTAB_USES_ALL_SCHEMAS   VtabConfigOption = 4
+	VTAB_ROLLBACK VTabConflictMode = 1
+	VTAB_IGNORE   VTabConflictMode = 2
+	VTAB_FAIL     VTabConflictMode = 3
+	VTAB_ABORT    VTabConflictMode = 4
+	VTAB_REPLACE  VTabConflictMode = 5
 )
 
-// VtabConfig configures various facets of the virtual table interface.
+// VTabOnConflict determines the virtual table conflict policy.
+//
+// https://sqlite.org/c3ref/vtab_on_conflict.html
+func (c *Conn) VTabOnConflict() VTabConflictMode {
+	r := c.call("sqlite3_vtab_on_conflict", uint64(c.handle))
+	return VTabConflictMode(r)
+}
+
+// VTabConfigOption is a virtual table configuration option.
+//
+// https://sqlite.org/c3ref/c_vtab_constraint_support.html
+type VTabConfigOption uint8
+
+const (
+	VTAB_CONSTRAINT_SUPPORT VTabConfigOption = 1
+	VTAB_INNOCUOUS          VTabConfigOption = 2
+	VTAB_DIRECTONLY         VTabConfigOption = 3
+	VTAB_USES_ALL_SCHEMAS   VTabConfigOption = 4
+)
+
+// VTabConfig configures various facets of the virtual table interface.
 //
 // https://sqlite.org/c3ref/vtab_config.html
-func (c *Conn) VtabConfig(op VtabConfigOption, args ...any) error {
+func (c *Conn) VTabConfig(op VTabConfigOption, args ...any) error {
 	var i uint64
 	if op == VTAB_CONSTRAINT_SUPPORT && len(args) > 0 {
 		if b, ok := args[0].(bool); ok && b {
@@ -147,7 +168,7 @@ type VTabOverloader interface {
 }
 
 // A VTabChecker allows a virtual table to report errors
-// to the PRAGMA integrity_check PRAGMA quick_check commands.
+// to the PRAGMA integrity_check and PRAGMA quick_check commands.
 //
 // Integrity should return an error if it finds problems in the content of the virtual table,
 // but should avoid returning a (wrapped) [Error], [ErrorCode] or [ExtendedErrorCode],
@@ -262,17 +283,43 @@ type IndexConstraintUsage struct {
 func (idx *IndexInfo) RHSValue(column int) (Value, error) {
 	defer idx.c.arena.mark()()
 	valPtr := idx.c.arena.new(ptrlen)
-	r := idx.c.call("sqlite3_vtab_rhs_value",
-		uint64(idx.handle), uint64(column), uint64(valPtr))
+	r := idx.c.call("sqlite3_vtab_rhs_value", uint64(idx.handle),
+		uint64(column), uint64(valPtr))
 	if err := idx.c.error(r); err != nil {
 		return Value{}, err
 	}
 	return Value{
-		sqlite: idx.c.sqlite,
+		c:      idx.c,
 		handle: util.ReadUint32(idx.c.mod, valPtr),
 	}, nil
 }
 
+// Collation returns the name of the collation for a virtual table constraint.
+//
+// https://sqlite.org/c3ref/vtab_collation.html
+func (idx *IndexInfo) Collation(column int) string {
+	r := idx.c.call("sqlite3_vtab_collation", uint64(idx.handle),
+		uint64(column))
+	return util.ReadString(idx.c.mod, uint32(r), _MAX_NAME)
+}
+
+// Distinct determines if a virtual table query is DISTINCT.
+//
+// https://sqlite.org/c3ref/vtab_distinct.html
+func (idx *IndexInfo) Distinct() int {
+	r := idx.c.call("sqlite3_vtab_distinct", uint64(idx.handle))
+	return int(r)
+}
+
+// In identifies and handles IN constraints.
+//
+// https://sqlite.org/c3ref/vtab_in.html
+func (idx *IndexInfo) In(column, handle int) bool {
+	r := idx.c.call("sqlite3_vtab_in", uint64(idx.handle),
+		uint64(column), uint64(handle))
+	return r != 0
+}
+
 func (idx *IndexInfo) load() {
 	// https://sqlite.org/c3ref/index_info.html
 	mod := idx.c.mod
@@ -368,12 +415,12 @@ const (
 )
 
 func vtabModuleCallback(i int) func(_ context.Context, _ api.Module, _, _, _, _, _ uint32) uint32 {
-	return func(ctx context.Context, mod api.Module, pMod, argc, argv, ppVTab, pzErr uint32) uint32 {
-		arg := make([]reflect.Value, 1+argc)
+	return func(ctx context.Context, mod api.Module, pMod, nArg, pArg, ppVTab, pzErr uint32) uint32 {
+		arg := make([]reflect.Value, 1+nArg)
 		arg[0] = reflect.ValueOf(ctx.Value(connKey{}))
 
-		for i := uint32(0); i < argc; i++ {
-			ptr := util.ReadUint32(mod, argv+i*ptrlen)
+		for i := uint32(0); i < nArg; i++ {
+			ptr := util.ReadUint32(mod, pArg+i*ptrlen)
 			arg[i+1] = reflect.ValueOf(util.ReadString(mod, ptr, _MAX_SQL_LENGTH))
 		}
 
@@ -415,11 +462,12 @@ func vtabBestIndexCallback(ctx context.Context, mod api.Module, pVTab, pIdxInfo
 	return vtabError(ctx, mod, pVTab, _VTAB_ERROR, err)
 }
 
-func vtabUpdateCallback(ctx context.Context, mod api.Module, pVTab, argc, argv, pRowID uint32) uint32 {
+func vtabUpdateCallback(ctx context.Context, mod api.Module, pVTab, nArg, pArg, pRowID uint32) uint32 {
 	vtab := vtabGetHandle(ctx, mod, pVTab).(VTabUpdater)
 
 	db := ctx.Value(connKey{}).(*Conn)
-	args := callbackArgs(db, argc, argv)
+	args := make([]Value, nArg)
+	callbackArgs(db, args, pArg)
 	rowID, err := vtab.Update(args...)
 	if err == nil {
 		util.WriteUint64(mod, pRowID, uint64(rowID))
@@ -436,13 +484,14 @@ func vtabRenameCallback(ctx context.Context, mod api.Module, pVTab, zNew uint32)
 
 func vtabFindFuncCallback(ctx context.Context, mod api.Module, pVTab, nArg, zName, pxFunc uint32) uint32 {
 	vtab := vtabGetHandle(ctx, mod, pVTab).(VTabOverloader)
-	fn, op := vtab.FindFunction(int(nArg), util.ReadString(mod, zName, _MAX_NAME))
-	if fn != nil {
-		handle := util.AddHandle(ctx, fn)
-		util.WriteUint32(mod, pxFunc, handle)
-		if op == 0 {
-			op = 1
-		}
+	f, op := vtab.FindFunction(int(nArg), util.ReadString(mod, zName, _MAX_NAME))
+	if op != 0 {
+		var wrapper uint32
+		wrapper = util.AddHandle(ctx, func(c Context, arg ...Value) {
+			defer util.DelHandle(ctx, wrapper)
+			f(c, arg...)
+		})
+		util.WriteUint32(mod, pxFunc, wrapper)
 	}
 	return uint32(op)
 }
@@ -517,13 +566,14 @@ func cursorCloseCallback(ctx context.Context, mod api.Module, pCur uint32) uint3
 	return vtabError(ctx, mod, 0, _VTAB_ERROR, err)
 }
 
-func cursorFilterCallback(ctx context.Context, mod api.Module, pCur, idxNum, idxStr, argc, argv uint32) uint32 {
+func cursorFilterCallback(ctx context.Context, mod api.Module, pCur, idxNum, idxStr, nArg, pArg uint32) uint32 {
 	cursor := vtabGetHandle(ctx, mod, pCur).(VTabCursor)
 	db := ctx.Value(connKey{}).(*Conn)
-	args := callbackArgs(db, argc, argv)
+	args := make([]Value, nArg)
+	callbackArgs(db, args, pArg)
 	var idxName string
 	if idxStr != 0 {
-		idxName = util.ReadString(mod, idxStr, _MAX_NAME)
+		idxName = util.ReadString(mod, idxStr, _MAX_LENGTH)
 	}
 	err := cursor.Filter(int(idxNum), idxName, args...)
 	return vtabError(ctx, mod, pCur, _CURSOR_ERROR, err)
@@ -574,7 +624,7 @@ func vtabError(ctx context.Context, mod api.Module, ptr, kind uint32, err error)
 		case _VTAB_ERROR:
 			ptr = ptr + 8 // zErrMsg
 		case _CURSOR_ERROR:
-			ptr = util.ReadUint32(mod, ptr) + 8 // pVtab->zErrMsg
+			ptr = util.ReadUint32(mod, ptr) + 8 // pVTab->zErrMsg
 		}
 		db := ctx.Value(connKey{}).(*Conn)
 		if ptr := util.ReadUint32(mod, ptr); ptr != 0 {

vtab_test.go

@@ -17,7 +17,7 @@ func ExampleCreateModule() {
 
 	err = sqlite3.CreateModule[seriesTable](db, "generate_series", nil,
 		func(db *sqlite3.Conn, module, schema, table string, arg ...string) (seriesTable, error) {
-			err := db.DeclareVtab(`CREATE TABLE x(value, start HIDDEN, stop HIDDEN, step HIDDEN)`)
+			err := db.DeclareVTab(`CREATE TABLE x(value, start HIDDEN, stop HIDDEN, step HIDDEN)`)
 			return seriesTable{}, err
 		})
 	if err != nil {