GoToSocial/vendor/github.com/ncruces/go-sqlite3/vfs/vfs.go

444 lines
13 KiB
Go

package vfs
import (
"context"
"crypto/rand"
"io"
"reflect"
"sync"
"time"
"github.com/ncruces/go-sqlite3/internal/util"
"github.com/ncruces/julianday"
"github.com/tetratelabs/wazero"
"github.com/tetratelabs/wazero/api"
)
// ExportHostFunctions is an internal API users need not call directly.
//
// ExportHostFunctions registers the required VFS host functions
// with the provided env module.
func ExportHostFunctions(env wazero.HostModuleBuilder) wazero.HostModuleBuilder {
util.ExportFuncII(env, "go_vfs_find", vfsFind)
util.ExportFuncIIJ(env, "go_localtime", vfsLocaltime)
util.ExportFuncIIII(env, "go_randomness", vfsRandomness)
util.ExportFuncIII(env, "go_sleep", vfsSleep)
util.ExportFuncIII(env, "go_current_time_64", vfsCurrentTime64)
util.ExportFuncIIIII(env, "go_full_pathname", vfsFullPathname)
util.ExportFuncIIII(env, "go_delete", vfsDelete)
util.ExportFuncIIIII(env, "go_access", vfsAccess)
util.ExportFuncIIIIIII(env, "go_open", vfsOpen)
util.ExportFuncII(env, "go_close", vfsClose)
util.ExportFuncIIIIJ(env, "go_read", vfsRead)
util.ExportFuncIIIIJ(env, "go_write", vfsWrite)
util.ExportFuncIIJ(env, "go_truncate", vfsTruncate)
util.ExportFuncIII(env, "go_sync", vfsSync)
util.ExportFuncIII(env, "go_file_size", vfsFileSize)
util.ExportFuncIIII(env, "go_file_control", vfsFileControl)
util.ExportFuncII(env, "go_sector_size", vfsSectorSize)
util.ExportFuncII(env, "go_device_characteristics", vfsDeviceCharacteristics)
util.ExportFuncIII(env, "go_lock", vfsLock)
util.ExportFuncIII(env, "go_unlock", vfsUnlock)
util.ExportFuncIII(env, "go_check_reserved_lock", vfsCheckReservedLock)
util.ExportFuncIIIIII(env, "go_shm_map", vfsShmMap)
util.ExportFuncIIIII(env, "go_shm_lock", vfsShmLock)
util.ExportFuncIII(env, "go_shm_unmap", vfsShmUnmap)
util.ExportFuncVI(env, "go_shm_barrier", vfsShmBarrier)
return env
}
func vfsFind(ctx context.Context, mod api.Module, zVfsName uint32) uint32 {
name := util.ReadString(mod, zVfsName, _MAX_NAME)
if vfs := Find(name); vfs != nil && vfs != (vfsOS{}) {
return 1
}
return 0
}
func vfsLocaltime(ctx context.Context, mod api.Module, pTm uint32, t int64) _ErrorCode {
tm := time.Unix(t, 0)
var isdst int
if tm.IsDST() {
isdst = 1
}
const size = 32 / 8
// https://pubs.opengroup.org/onlinepubs/7908799/xsh/time.h.html
util.WriteUint32(mod, pTm+0*size, uint32(tm.Second()))
util.WriteUint32(mod, pTm+1*size, uint32(tm.Minute()))
util.WriteUint32(mod, pTm+2*size, uint32(tm.Hour()))
util.WriteUint32(mod, pTm+3*size, uint32(tm.Day()))
util.WriteUint32(mod, pTm+4*size, uint32(tm.Month()-time.January))
util.WriteUint32(mod, pTm+5*size, uint32(tm.Year()-1900))
util.WriteUint32(mod, pTm+6*size, uint32(tm.Weekday()-time.Sunday))
util.WriteUint32(mod, pTm+7*size, uint32(tm.YearDay()-1))
util.WriteUint32(mod, pTm+8*size, uint32(isdst))
return _OK
}
func vfsRandomness(ctx context.Context, mod api.Module, pVfs uint32, nByte int32, zByte uint32) uint32 {
mem := util.View(mod, zByte, uint64(nByte))
n, _ := rand.Reader.Read(mem)
return uint32(n)
}
func vfsSleep(ctx context.Context, mod api.Module, pVfs uint32, nMicro int32) _ErrorCode {
time.Sleep(time.Duration(nMicro) * time.Microsecond)
return _OK
}
func vfsCurrentTime64(ctx context.Context, mod api.Module, pVfs, piNow uint32) _ErrorCode {
day, nsec := julianday.Date(time.Now())
msec := day*86_400_000 + nsec/1_000_000
util.WriteUint64(mod, piNow, uint64(msec))
return _OK
}
func vfsFullPathname(ctx context.Context, mod api.Module, pVfs, zRelative uint32, nFull int32, zFull uint32) _ErrorCode {
vfs := vfsGet(mod, pVfs)
path := util.ReadString(mod, zRelative, _MAX_PATHNAME)
path, err := vfs.FullPathname(path)
if len(path) >= int(nFull) {
return _CANTOPEN_FULLPATH
}
util.WriteString(mod, zFull, path)
return vfsErrorCode(err, _CANTOPEN_FULLPATH)
}
func vfsDelete(ctx context.Context, mod api.Module, pVfs, zPath, syncDir uint32) _ErrorCode {
vfs := vfsGet(mod, pVfs)
path := util.ReadString(mod, zPath, _MAX_PATHNAME)
err := vfs.Delete(path, syncDir != 0)
return vfsErrorCode(err, _IOERR_DELETE)
}
func vfsAccess(ctx context.Context, mod api.Module, pVfs, zPath uint32, flags AccessFlag, pResOut uint32) _ErrorCode {
vfs := vfsGet(mod, pVfs)
path := util.ReadString(mod, zPath, _MAX_PATHNAME)
ok, err := vfs.Access(path, flags)
var res uint32
if ok {
res = 1
}
util.WriteUint32(mod, pResOut, res)
return vfsErrorCode(err, _IOERR_ACCESS)
}
func vfsOpen(ctx context.Context, mod api.Module, pVfs, zPath, pFile uint32, flags OpenFlag, pOutFlags, pOutVFS uint32) _ErrorCode {
vfs := vfsGet(mod, pVfs)
name := GetFilename(ctx, mod, zPath, flags)
var file File
var err error
if ffs, ok := vfs.(VFSFilename); ok {
file, flags, err = ffs.OpenFilename(name, flags)
} else {
file, flags, err = vfs.Open(name.String(), flags)
}
if err != nil {
return vfsErrorCode(err, _CANTOPEN)
}
if file, ok := file.(FilePowersafeOverwrite); ok {
if b, ok := util.ParseBool(name.URIParameter("psow")); ok {
file.SetPowersafeOverwrite(b)
}
}
if file, ok := file.(FileSharedMemory); ok &&
pOutVFS != 0 && file.SharedMemory() != nil {
util.WriteUint32(mod, pOutVFS, 1)
}
if pOutFlags != 0 {
util.WriteUint32(mod, pOutFlags, uint32(flags))
}
vfsFileRegister(ctx, mod, pFile, file)
return _OK
}
func vfsClose(ctx context.Context, mod api.Module, pFile uint32) _ErrorCode {
err := vfsFileClose(ctx, mod, pFile)
return vfsErrorCode(err, _IOERR_CLOSE)
}
func vfsRead(ctx context.Context, mod api.Module, pFile, zBuf uint32, iAmt int32, iOfst int64) _ErrorCode {
file := vfsFileGet(ctx, mod, pFile).(File)
buf := util.View(mod, zBuf, uint64(iAmt))
n, err := file.ReadAt(buf, iOfst)
if n == int(iAmt) {
return _OK
}
if err != io.EOF {
return vfsErrorCode(err, _IOERR_READ)
}
clear(buf[n:])
return _IOERR_SHORT_READ
}
func vfsWrite(ctx context.Context, mod api.Module, pFile, zBuf uint32, iAmt int32, iOfst int64) _ErrorCode {
file := vfsFileGet(ctx, mod, pFile).(File)
buf := util.View(mod, zBuf, uint64(iAmt))
_, err := file.WriteAt(buf, iOfst)
return vfsErrorCode(err, _IOERR_WRITE)
}
func vfsTruncate(ctx context.Context, mod api.Module, pFile uint32, nByte int64) _ErrorCode {
file := vfsFileGet(ctx, mod, pFile).(File)
err := file.Truncate(nByte)
return vfsErrorCode(err, _IOERR_TRUNCATE)
}
func vfsSync(ctx context.Context, mod api.Module, pFile uint32, flags SyncFlag) _ErrorCode {
file := vfsFileGet(ctx, mod, pFile).(File)
err := file.Sync(flags)
return vfsErrorCode(err, _IOERR_FSYNC)
}
func vfsFileSize(ctx context.Context, mod api.Module, pFile, pSize uint32) _ErrorCode {
file := vfsFileGet(ctx, mod, pFile).(File)
size, err := file.Size()
util.WriteUint64(mod, pSize, uint64(size))
return vfsErrorCode(err, _IOERR_SEEK)
}
func vfsLock(ctx context.Context, mod api.Module, pFile uint32, eLock LockLevel) _ErrorCode {
file := vfsFileGet(ctx, mod, pFile).(File)
err := file.Lock(eLock)
return vfsErrorCode(err, _IOERR_LOCK)
}
func vfsUnlock(ctx context.Context, mod api.Module, pFile uint32, eLock LockLevel) _ErrorCode {
file := vfsFileGet(ctx, mod, pFile).(File)
err := file.Unlock(eLock)
return vfsErrorCode(err, _IOERR_UNLOCK)
}
func vfsCheckReservedLock(ctx context.Context, mod api.Module, pFile, pResOut uint32) _ErrorCode {
file := vfsFileGet(ctx, mod, pFile).(File)
locked, err := file.CheckReservedLock()
var res uint32
if locked {
res = 1
}
util.WriteUint32(mod, pResOut, res)
return vfsErrorCode(err, _IOERR_CHECKRESERVEDLOCK)
}
func vfsFileControl(ctx context.Context, mod api.Module, pFile uint32, op _FcntlOpcode, pArg uint32) _ErrorCode {
file := vfsFileGet(ctx, mod, pFile).(File)
switch op {
case _FCNTL_LOCKSTATE:
if file, ok := file.(FileLockState); ok {
util.WriteUint32(mod, pArg, uint32(file.LockState()))
return _OK
}
case _FCNTL_PERSIST_WAL:
if file, ok := file.(FilePersistentWAL); ok {
if i := util.ReadUint32(mod, pArg); int32(i) >= 0 {
file.SetPersistentWAL(i != 0)
} else if file.PersistentWAL() {
util.WriteUint32(mod, pArg, 1)
} else {
util.WriteUint32(mod, pArg, 0)
}
return _OK
}
case _FCNTL_POWERSAFE_OVERWRITE:
if file, ok := file.(FilePowersafeOverwrite); ok {
if i := util.ReadUint32(mod, pArg); int32(i) >= 0 {
file.SetPowersafeOverwrite(i != 0)
} else if file.PowersafeOverwrite() {
util.WriteUint32(mod, pArg, 1)
} else {
util.WriteUint32(mod, pArg, 0)
}
return _OK
}
case _FCNTL_CHUNK_SIZE:
if file, ok := file.(FileChunkSize); ok {
size := util.ReadUint32(mod, pArg)
file.ChunkSize(int(size))
return _OK
}
case _FCNTL_SIZE_HINT:
if file, ok := file.(FileSizeHint); ok {
size := util.ReadUint64(mod, pArg)
err := file.SizeHint(int64(size))
return vfsErrorCode(err, _IOERR_TRUNCATE)
}
case _FCNTL_HAS_MOVED:
if file, ok := file.(FileHasMoved); ok {
moved, err := file.HasMoved()
var res uint32
if moved {
res = 1
}
util.WriteUint32(mod, pArg, res)
return vfsErrorCode(err, _IOERR_FSTAT)
}
case _FCNTL_OVERWRITE:
if file, ok := file.(FileOverwrite); ok {
err := file.Overwrite()
return vfsErrorCode(err, _IOERR)
}
case _FCNTL_COMMIT_PHASETWO:
if file, ok := file.(FileCommitPhaseTwo); ok {
err := file.CommitPhaseTwo()
return vfsErrorCode(err, _IOERR)
}
case _FCNTL_BEGIN_ATOMIC_WRITE:
if file, ok := file.(FileBatchAtomicWrite); ok {
err := file.BeginAtomicWrite()
return vfsErrorCode(err, _IOERR_BEGIN_ATOMIC)
}
case _FCNTL_COMMIT_ATOMIC_WRITE:
if file, ok := file.(FileBatchAtomicWrite); ok {
err := file.CommitAtomicWrite()
return vfsErrorCode(err, _IOERR_COMMIT_ATOMIC)
}
case _FCNTL_ROLLBACK_ATOMIC_WRITE:
if file, ok := file.(FileBatchAtomicWrite); ok {
err := file.RollbackAtomicWrite()
return vfsErrorCode(err, _IOERR_ROLLBACK_ATOMIC)
}
case _FCNTL_CKPT_DONE:
if file, ok := file.(FileCheckpoint); ok {
err := file.CheckpointDone()
return vfsErrorCode(err, _IOERR)
}
case _FCNTL_CKPT_START:
if file, ok := file.(FileCheckpoint); ok {
err := file.CheckpointStart()
return vfsErrorCode(err, _IOERR)
}
case _FCNTL_PRAGMA:
if file, ok := file.(FilePragma); ok {
ptr := util.ReadUint32(mod, pArg+1*ptrlen)
name := util.ReadString(mod, ptr, _MAX_SQL_LENGTH)
var value string
if ptr := util.ReadUint32(mod, pArg+2*ptrlen); ptr != 0 {
value = util.ReadString(mod, ptr, _MAX_SQL_LENGTH)
}
out, err := file.Pragma(name, value)
ret := vfsErrorCode(err, _ERROR)
if ret == _ERROR {
out = err.Error()
}
if out != "" {
fn := mod.ExportedFunction("malloc")
stack := [...]uint64{uint64(len(out) + 1)}
if err := fn.CallWithStack(ctx, stack[:]); err != nil {
panic(err)
}
util.WriteUint32(mod, pArg, uint32(stack[0]))
util.WriteString(mod, uint32(stack[0]), out)
}
return ret
}
}
// Consider also implementing these opcodes (in use by SQLite):
// _FCNTL_BUSYHANDLER
// _FCNTL_LAST_ERRNO
// _FCNTL_SYNC
return _NOTFOUND
}
func vfsSectorSize(ctx context.Context, mod api.Module, pFile uint32) uint32 {
file := vfsFileGet(ctx, mod, pFile).(File)
return uint32(file.SectorSize())
}
func vfsDeviceCharacteristics(ctx context.Context, mod api.Module, pFile uint32) DeviceCharacteristic {
file := vfsFileGet(ctx, mod, pFile).(File)
return file.DeviceCharacteristics()
}
var shmBarrier sync.Mutex
func vfsShmBarrier(ctx context.Context, mod api.Module, pFile uint32) {
shmBarrier.Lock()
defer shmBarrier.Unlock()
}
func vfsShmMap(ctx context.Context, mod api.Module, pFile uint32, iRegion, szRegion int32, bExtend, pp uint32) _ErrorCode {
shm := vfsFileGet(ctx, mod, pFile).(FileSharedMemory).SharedMemory()
p, rc := shm.shmMap(ctx, mod, iRegion, szRegion, bExtend != 0)
util.WriteUint32(mod, pp, p)
return rc
}
func vfsShmLock(ctx context.Context, mod api.Module, pFile uint32, offset, n int32, flags _ShmFlag) _ErrorCode {
shm := vfsFileGet(ctx, mod, pFile).(FileSharedMemory).SharedMemory()
return shm.shmLock(offset, n, flags)
}
func vfsShmUnmap(ctx context.Context, mod api.Module, pFile, bDelete uint32) _ErrorCode {
shm := vfsFileGet(ctx, mod, pFile).(FileSharedMemory).SharedMemory()
shm.shmUnmap(bDelete != 0)
return _OK
}
func vfsGet(mod api.Module, pVfs uint32) VFS {
var name string
if pVfs != 0 {
const zNameOffset = 16
name = util.ReadString(mod, util.ReadUint32(mod, pVfs+zNameOffset), _MAX_NAME)
}
if vfs := Find(name); vfs != nil {
return vfs
}
panic(util.NoVFSErr + util.ErrorString(name))
}
func vfsFileRegister(ctx context.Context, mod api.Module, pFile uint32, file File) {
const fileHandleOffset = 4
id := util.AddHandle(ctx, file)
util.WriteUint32(mod, pFile+fileHandleOffset, id)
}
func vfsFileGet(ctx context.Context, mod api.Module, pFile uint32) any {
const fileHandleOffset = 4
id := util.ReadUint32(mod, pFile+fileHandleOffset)
return util.GetHandle(ctx, id)
}
func vfsFileClose(ctx context.Context, mod api.Module, pFile uint32) error {
const fileHandleOffset = 4
id := util.ReadUint32(mod, pFile+fileHandleOffset)
return util.DelHandle(ctx, id)
}
func vfsErrorCode(err error, def _ErrorCode) _ErrorCode {
if err == nil {
return _OK
}
switch v := reflect.ValueOf(err); v.Kind() {
case reflect.Uint8, reflect.Uint16, reflect.Uint32:
return _ErrorCode(v.Uint())
}
return def
}