Refactor.

driver/driver.go

@@ -274,6 +274,7 @@ func (n *connector) Connect(ctx context.Context) (res driver.Conn, err error) {
 //	if err != nil {
 //		log.Fatal(err)
 //	}
+//	defer conn.Close()
 //
 //	err = conn.Raw(func(driverConn any) error {
 //		conn := driverConn.(driver.Conn)

driver/util.go

@@ -12,3 +12,63 @@ func namedValues(args []driver.Value) []driver.NamedValue {
 	}
 	return named
 }
+
+func notWhitespace(sql string) bool {
+	const (
+		code = iota
+		slash
+		minus
+		ccomment
+		sqlcomment
+		endcomment
+	)
+
+	state := code
+	for _, b := range ([]byte)(sql) {
+		if b == 0 {
+			break
+		}
+
+		switch state {
+		case code:
+			switch b {
+			case '/':
+				state = slash
+			case '-':
+				state = minus
+			case ' ', ';', '\t', '\n', '\v', '\f', '\r':
+				continue
+			default:
+				return true
+			}
+		case slash:
+			if b != '*' {
+				return true
+			}
+			state = ccomment
+		case minus:
+			if b != '-' {
+				return true
+			}
+			state = sqlcomment
+		case ccomment:
+			if b == '*' {
+				state = endcomment
+			}
+		case sqlcomment:
+			if b == '\n' {
+				state = code
+			}
+		case endcomment:
+			switch b {
+			case '/':
+				state = code
+			case '*':
+				state = endcomment
+			default:
+				state = ccomment
+			}
+		}
+	}
+	return state == slash || state == minus
+}

driver/util_test.go

@@ -1,9 +1,13 @@
 package driver
 
 import (
+	"context"
 	"database/sql/driver"
 	"reflect"
 	"testing"
+
+	_ "github.com/ncruces/go-sqlite3/embed"
+	_ "github.com/ncruces/go-sqlite3/internal/testcfg"
 )
 
 func Test_namedValues(t *testing.T) {
@@ -16,3 +20,67 @@ func Test_namedValues(t *testing.T) {
 		t.Errorf("got %v, want %v", got, want)
 	}
 }
+
+func Fuzz_notWhitespace(f *testing.F) {
+	f.Add("")
+	f.Add(" ")
+	f.Add(";")
+	f.Add("0")
+	f.Add("-")
+	f.Add("-0")
+	f.Add("--")
+	f.Add("--0")
+	f.Add("--\n")
+	f.Add("--0\n")
+	f.Add("/0")
+	f.Add("/*")
+	f.Add("/*/")
+	f.Add("/**")
+	f.Add("/*0")
+	f.Add("/**/")
+	f.Add("/***/")
+	f.Add("/**0/")
+	f.Add("\v")
+	f.Add(" \v")
+	f.Add("\xf0")
+	f.Add("\000")
+
+	db, err := Open(":memory:")
+	if err != nil {
+		f.Fatal(err)
+	}
+	defer db.Close()
+
+	f.Fuzz(func(t *testing.T, str string) {
+		if len(str) > 128 {
+			t.SkipNow()
+		}
+
+		c, err := db.Conn(context.Background())
+		if err != nil {
+			t.Fatal(err)
+		}
+		defer c.Close()
+
+		c.Raw(func(driverConn any) error {
+			conn := driverConn.(*conn).Conn
+			stmt, tail, err := conn.Prepare(str)
+			stmt.Close()
+
+			// It's hard to be bug for bug compatible with SQLite.
+			// We settle for somewhat less:
+			//   - if SQLite reports whitespace, we must too
+			//   - if we report whitespace, SQLite must not parse a statement
+			if notWhitespace(str) {
+				if stmt == nil && tail == "" && err == nil {
+					t.Errorf("was whitespace: %q", str)
+				}
+			} else {
+				if stmt != nil {
+					t.Errorf("was not whitespace: %q (%v)", str, err)
+				}
+			}
+			return nil
+		})
+	})
+}

driver/whitespace.go

@@ -1,61 +0,0 @@
-package driver
-
-func notWhitespace(sql string) bool {
-	const (
-		code = iota
-		slash
-		minus
-		ccomment
-		sqlcomment
-		endcomment
-	)
-
-	state := code
-	for _, b := range ([]byte)(sql) {
-		if b == 0 {
-			break
-		}
-
-		switch state {
-		case code:
-			switch b {
-			case '/':
-				state = slash
-			case '-':
-				state = minus
-			case ' ', ';', '\t', '\n', '\v', '\f', '\r':
-				continue
-			default:
-				return true
-			}
-		case slash:
-			if b != '*' {
-				return true
-			}
-			state = ccomment
-		case minus:
-			if b != '-' {
-				return true
-			}
-			state = sqlcomment
-		case ccomment:
-			if b == '*' {
-				state = endcomment
-			}
-		case sqlcomment:
-			if b == '\n' {
-				state = code
-			}
-		case endcomment:
-			switch b {
-			case '/':
-				state = code
-			case '*':
-				state = endcomment
-			default:
-				state = ccomment
-			}
-		}
-	}
-	return state == slash || state == minus
-}

driver/whitespace_test.go

@@ -1,73 +0,0 @@
-package driver
-
-import (
-	"context"
-	"testing"
-
-	_ "github.com/ncruces/go-sqlite3/embed"
-	_ "github.com/ncruces/go-sqlite3/internal/testcfg"
-)
-
-func Fuzz_notWhitespace(f *testing.F) {
-	f.Add("")
-	f.Add(" ")
-	f.Add(";")
-	f.Add("0")
-	f.Add("-")
-	f.Add("-0")
-	f.Add("--")
-	f.Add("--0")
-	f.Add("--\n")
-	f.Add("--0\n")
-	f.Add("/0")
-	f.Add("/*")
-	f.Add("/*/")
-	f.Add("/**")
-	f.Add("/*0")
-	f.Add("/**/")
-	f.Add("/***/")
-	f.Add("/**0/")
-	f.Add("\v")
-	f.Add(" \v")
-	f.Add("\xf0")
-	f.Add("\000")
-
-	db, err := Open(":memory:")
-	if err != nil {
-		f.Fatal(err)
-	}
-	defer db.Close()
-
-	f.Fuzz(func(t *testing.T, str string) {
-		if len(str) > 128 {
-			t.SkipNow()
-		}
-
-		c, err := db.Conn(context.Background())
-		if err != nil {
-			t.Fatal(err)
-		}
-		defer c.Close()
-
-		c.Raw(func(driverConn any) error {
-			conn := driverConn.(*conn).Conn
-			stmt, tail, err := conn.Prepare(str)
-			stmt.Close()
-
-			// It's hard to be bug for bug compatible with SQLite.
-			// We settle for somewhat less:
-			//   - if SQLite reports whitespace, we must too
-			//   - if we report whitespace, SQLite must not parse a statement
-			if notWhitespace(str) {
-				if stmt == nil && tail == "" && err == nil {
-					t.Errorf("was whitespace: %q", str)
-				}
-			} else {
-				if stmt != nil {
-					t.Errorf("was not whitespace: %q (%v)", str, err)
-				}
-			}
-			return nil
-		})
-	})
-}

ext/blobio/blob.go

@@ -44,6 +44,8 @@ func Register(db *sqlite3.Conn) error {
 type OpenCallback func(*sqlite3.Blob, ...sqlite3.Value) error
 
 func readblob(ctx sqlite3.Context, arg ...sqlite3.Value) {
+	_ = arg[5] // bounds check
+
 	blob, err := getAuxBlob(ctx, arg, false)
 	if err != nil {
 		ctx.ResultError(err)
@@ -78,6 +80,8 @@ func readblob(ctx sqlite3.Context, arg ...sqlite3.Value) {
 }
 
 func writeblob(ctx sqlite3.Context, arg ...sqlite3.Value) {
+	_ = arg[5] // bounds check
+
 	blob, err := getAuxBlob(ctx, arg, true)
 	if err != nil {
 		ctx.ResultError(err)

ext/regexp/regexp.go

@@ -76,6 +76,7 @@ func load(ctx sqlite3.Context, i int, expr string) (*regexp.Regexp, error) {
 }
 
 func regex(ctx sqlite3.Context, arg ...sqlite3.Value) {
+	_ = arg[1] // bounds check
 	re, err := load(ctx, 0, arg[0].Text())
 	if err != nil {
 		ctx.ResultError(err)
@@ -165,6 +166,8 @@ func regexInstr(ctx sqlite3.Context, arg ...sqlite3.Value) {
 }
 
 func regexReplace(ctx sqlite3.Context, arg ...sqlite3.Value) {
+	_ = arg[2] // bounds check
+
 	re, err := load(ctx, 1, arg[1].Text())
 	if err != nil {
 		ctx.ResultError(err)

ext/unicode/unicode.go

@@ -189,6 +189,7 @@ func like(ctx sqlite3.Context, arg ...sqlite3.Value) {
 			return
 		}
 	}
+	_ = arg[1] // bounds check
 
 	type likeData struct {
 		*regexp.Regexp

internal/util/mmap_unix.go

@@ -39,13 +39,13 @@ func (s *mmapState) new(ctx context.Context, mod api.Module, size int32) *Mapped
 	// Save the newly allocated region.
 	ptr := uint32(stack[0])
 	buf := View(mod, ptr, uint64(size))
-	addr := unsafe.Pointer(&buf[0])
-	s.regions = append(s.regions, &MappedRegion{
+	res := &MappedRegion{
 		Ptr:  ptr,
-		addr: addr,
 		size: size,
-	})
-	return s.regions[len(s.regions)-1]
+		addr: unsafe.Pointer(&buf[0]),
+	}
+	s.regions = append(s.regions, res)
+	return res
 }
 
 type MappedRegion struct {

sqlite.go

@@ -265,10 +265,11 @@ func (a *arena) mark() (reset func()) {
 	ptrs := len(a.ptrs)
 	next := a.next
 	return func() {
-		for _, ptr := range a.ptrs[ptrs:] {
+		rest := a.ptrs[ptrs:]
+		for _, ptr := range a.ptrs[:ptrs] {
 			a.sqlt.free(ptr)
 		}
-		a.ptrs = a.ptrs[:ptrs]
+		a.ptrs = rest
 		a.next = next
 	}
 }

vfs/lock.go

@@ -20,12 +20,10 @@ const (
 )
 
 func (f *vfsFile) Lock(lock LockLevel) error {
-	// Argument check. SQLite never explicitly requests a pending lock.
-	if lock != LOCK_SHARED && lock != LOCK_RESERVED && lock != LOCK_EXCLUSIVE {
-		panic(util.AssertErr())
-	}
-
 	switch {
+	case lock != LOCK_SHARED && lock != LOCK_RESERVED && lock != LOCK_EXCLUSIVE:
+		// Argument check. SQLite never explicitly requests a pending lock.
+		panic(util.AssertErr())
 	case f.lock < LOCK_NONE || f.lock > LOCK_EXCLUSIVE:
 		// Connection state check.
 		panic(util.AssertErr())
@@ -87,13 +85,12 @@ func (f *vfsFile) Lock(lock LockLevel) error {
 }
 
 func (f *vfsFile) Unlock(lock LockLevel) error {
-	// Argument check.
-	if lock != LOCK_NONE && lock != LOCK_SHARED {
+	switch {
+	case lock != LOCK_NONE && lock != LOCK_SHARED:
+		// Argument check.
 		panic(util.AssertErr())
-	}
-
-	// Connection state check.
-	if f.lock < LOCK_NONE || f.lock > LOCK_EXCLUSIVE {
+	case f.lock < LOCK_NONE || f.lock > LOCK_EXCLUSIVE:
+		// Connection state check.
 		panic(util.AssertErr())
 	}
 

vfs/shm_bsd.go

@@ -22,7 +22,7 @@ type vfsShmParent struct {
 
 	refs int // +checklocks:vfsShmListMtx
 
-	lock [_SHM_NLOCK]int16 // +checklocks:Mutex
+	lock [_SHM_NLOCK]int8 // +checklocks:Mutex
 	sync.Mutex
 }
 
@@ -184,10 +184,22 @@ func (s *vfsShm) shmLock(offset, n int32, flags _ShmFlag) _ErrorCode {
 		return rc
 	}
 
-	// Obtain/release the appropriate file lock.
+	// Obtain/release the appropriate file locks.
 	switch {
 	case flags&_SHM_UNLOCK != 0:
-		return osUnlock(s.File, _SHM_BASE+int64(offset), int64(n))
+		begin, end := offset, offset+n
+		for i := begin; i < end; i++ {
+			if s.vfsShmParent.lock[i] != 0 {
+				if i > begin {
+					rc |= osUnlock(s.File, _SHM_BASE+int64(begin), int64(i-begin))
+				}
+				begin = i + 1
+			}
+		}
+		if end > begin {
+			rc |= osUnlock(s.File, _SHM_BASE+int64(begin), int64(end-begin))
+		}
+		return rc
 	case flags&_SHM_SHARED != 0:
 		rc = osReadLock(s.File, _SHM_BASE+int64(offset), int64(n))
 	case flags&_SHM_EXCLUSIVE != 0:
@@ -196,7 +208,7 @@ func (s *vfsShm) shmLock(offset, n int32, flags _ShmFlag) _ErrorCode {
 		panic(util.AssertErr())
 	}
 
-	// Release the local lock.
+	// Release the local lock we had acquired.
 	if rc != _OK {
 		s.shmMemLock(offset, n, flags^(_SHM_UNLOCK|_SHM_LOCK))
 	}

vfs/shm_dotlk.go

@@ -18,7 +18,7 @@ type vfsShmParent struct {
 	shared [][_WALINDEX_PGSZ]byte
 	refs   int // +checklocks:vfsShmListMtx
 
-	lock [_SHM_NLOCK]int16 // +checklocks:Mutex
+	lock [_SHM_NLOCK]int8 // +checklocks:Mutex
 	sync.Mutex
 }
 

vfs/shm_memlk.go

@@ -10,9 +10,6 @@ func (s *vfsShm) shmMemLock(offset, n int32, flags _ShmFlag) _ErrorCode {
 	case flags&_SHM_UNLOCK != 0:
 		for i := offset; i < offset+n; i++ {
 			if s.lock[i] {
-				if s.vfsShmParent.lock[i] == 0 {
-					panic(util.AssertErr())
-				}
 				if s.vfsShmParent.lock[i] <= 0 {
 					s.vfsShmParent.lock[i] = 0
 				} else {
@@ -23,20 +20,21 @@ func (s *vfsShm) shmMemLock(offset, n int32, flags _ShmFlag) _ErrorCode {
 		}
 	case flags&_SHM_SHARED != 0:
 		for i := offset; i < offset+n; i++ {
-			if s.lock[i] {
-				panic(util.AssertErr())
-			}
-			if s.vfsShmParent.lock[i]+1 <= 0 {
+			if !s.lock[i] &&
+				s.vfsShmParent.lock[i]+1 <= 0 {
 				return _BUSY
 			}
 		}
 		for i := offset; i < offset+n; i++ {
-			s.vfsShmParent.lock[i]++
-			s.lock[i] = true
+			if !s.lock[i] {
+				s.vfsShmParent.lock[i]++
+				s.lock[i] = true
+			}
 		}
 	case flags&_SHM_EXCLUSIVE != 0:
 		for i := offset; i < offset+n; i++ {
 			if s.lock[i] {
+				// SQLite never requests an exclusive lock that it already holds.
 				panic(util.AssertErr())
 			}
 			if s.vfsShmParent.lock[i] != 0 {

vfs/shm_ofd.go

@@ -110,7 +110,12 @@ func (s *vfsShm) shmMap(ctx context.Context, mod api.Module, id, size int32, ext
 
 func (s *vfsShm) shmLock(offset, n int32, flags _ShmFlag) _ErrorCode {
 	// Argument check.
-	if n <= 0 || offset < 0 || offset+n > _SHM_NLOCK {
+	switch {
+	case n <= 0:
+		panic(util.AssertErr())
+	case offset < 0 || offset+n > _SHM_NLOCK:
+		panic(util.AssertErr())
+	case n != 1 && flags&_SHM_EXCLUSIVE == 0:
 		panic(util.AssertErr())
 	}
 	switch flags {
@@ -123,9 +128,6 @@ func (s *vfsShm) shmLock(offset, n int32, flags _ShmFlag) _ErrorCode {
 	default:
 		panic(util.AssertErr())
 	}
-	if n != 1 && flags&_SHM_EXCLUSIVE == 0 {
-		panic(util.AssertErr())
-	}
 
 	var timeout time.Duration
 	if s.blocking {