Windows fixes.

embed/build.sh

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

embed/init.go

@@ -5,6 +5,9 @@
 //
 //	import _ "github.com/ncruces/go-sqlite3/embed"
 //
+// The following optional features are compiled in:
+// math functions, JSON, FTS3/4/5, R*Tree, GeoPoly.
+//
 // You can obtain this build of SQLite from:
 // https://github.com/ncruces/go-sqlite3/tree/main/embed
 package embed

vfs.go

@@ -169,6 +169,8 @@ func vfsDelete(ctx context.Context, mod api.Module, pVfs, zPath, syncDir uint32)
 		return _OK
 	}
 	if err != nil {
+		// TODO: fix windows.ERROR_SHARING_VIOLATION
+		// https://github.com/golang/go/issues/32088
 		return uint32(IOERR_DELETE)
 	}
 	if runtime.GOOS != "windows" && syncDir != 0 {

vfs_windows.go

@@ -63,6 +63,9 @@ func (vfsOSMethods) ReleaseLock(file *os.File, state vfsLockState) xErrorCode {
 func (vfsOSMethods) unlock(file *os.File, start, len uint32) xErrorCode {
 	err := windows.UnlockFileEx(windows.Handle(file.Fd()),
 		0, len, 0, &windows.Overlapped{Offset: start})
+	if err == windows.ERROR_NOT_LOCKED {
+		return _OK
+	}
 	if err != nil {
 		return IOERR_UNLOCK
 	}
@@ -95,8 +98,14 @@ func (vfsOSMethods) lockErrorCode(err error, def xErrorCode) xErrorCode {
 	if err == nil {
 		return _OK
 	}
-	if errno, _ := err.(syscall.Errno); errno == windows.ERROR_INVALID_HANDLE {
-		return def
+	if errno, ok := err.(syscall.Errno); ok {
+		// https://devblogs.microsoft.com/oldnewthing/20140905-00/?p=63
+		switch errno {
+		case
+			windows.ERROR_LOCK_VIOLATION,
+			windows.ERROR_IO_PENDING:
+			return xErrorCode(BUSY)
+		}
 	}
-	return xErrorCode(BUSY)
+	return def
 }