Files
tinygo/src/syscall/syscall_libc_wasi.go
T
Ayke van Laethem 66da29e89f wasip2: add stubs to get internal/syscall/unix to work
This fixes lots of broken tests in stdlib packages in Go 1.24.
2025-02-25 14:41:42 +01:00

501 lines
14 KiB
Go

//go:build js || wasip1 || wasip2
// Note: also including js in here because it also uses wasi-libc.
package syscall
import (
"internal/itoa"
"unsafe"
)
// https://github.com/WebAssembly/wasi-libc/blob/main/expected/wasm32-wasi/predefined-macros.txt
// disagrees with ../../lib/wasi-libc/libc-top-half/musl/arch/wasm32/bits/signal.h for SIGCHLD?
// https://github.com/WebAssembly/wasi-libc/issues/271
type Signal int
const (
SIGINT Signal = 2
SIGQUIT Signal = 3
SIGILL Signal = 4
SIGTRAP Signal = 5
SIGABRT Signal = 6
SIGBUS Signal = 7
SIGFPE Signal = 8
SIGKILL Signal = 9
SIGSEGV Signal = 11
SIGPIPE Signal = 13
SIGTERM Signal = 15
SIGCHLD Signal = 17
)
func (s Signal) Signal() {}
func (s Signal) String() string {
if 0 <= s && int(s) < len(signals) {
str := signals[s]
if str != "" {
return str
}
}
return "signal " + itoa.Itoa(int(s))
}
var signals = [...]string{}
const (
Stdin = 0
Stdout = 1
Stderr = 2
)
const (
__WASI_OFLAGS_CREAT = 1
__WASI_OFLAGS_DIRECTORY = 2
__WASI_OFLAGS_EXCL = 4
__WASI_OFLAGS_TRUNC = 8
__WASI_FDFLAGS_APPEND = 1
__WASI_FDFLAGS_DSYNC = 2
__WASI_FDFLAGS_NONBLOCK = 4
__WASI_FDFLAGS_RSYNC = 8
__WASI_FDFLAGS_SYNC = 16
__WASI_FILETYPE_UNKNOWN = 0
__WASI_FILETYPE_BLOCK_DEVICE = 1
__WASI_FILETYPE_CHARACTER_DEVICE = 2
__WASI_FILETYPE_DIRECTORY = 3
__WASI_FILETYPE_REGULAR_FILE = 4
__WASI_FILETYPE_SOCKET_DGRAM = 5
__WASI_FILETYPE_SOCKET_STREAM = 6
__WASI_FILETYPE_SYMBOLIC_LINK = 7
// ../../lib/wasi-libc/libc-bottom-half/headers/public/__header_fcntl.h
O_NOFOLLOW = 0x01000000
O_RDONLY = 0x04000000
O_WRONLY = 0x10000000
O_RDWR = O_RDONLY | O_WRONLY
O_CREAT = __WASI_OFLAGS_CREAT << 12
O_TRUNC = __WASI_OFLAGS_TRUNC << 12
O_EXCL = __WASI_OFLAGS_EXCL << 12
O_DIRECTORY = __WASI_OFLAGS_DIRECTORY << 12
O_APPEND = __WASI_FDFLAGS_APPEND
O_DSYNC = __WASI_FDFLAGS_DSYNC
O_NONBLOCK = __WASI_FDFLAGS_NONBLOCK
O_RSYNC = __WASI_FDFLAGS_RSYNC
O_SYNC = __WASI_FDFLAGS_SYNC
O_CLOEXEC = 0
// ../../lib/wasi-libc/sysroot/include/sys/mman.h
MAP_FILE = 0
MAP_SHARED = 0x01
MAP_PRIVATE = 0x02
MAP_ANON = 0x20
MAP_ANONYMOUS = MAP_ANON
// ../../lib/wasi-libc/sysroot/include/sys/mman.h
PROT_NONE = 0
PROT_READ = 1
PROT_WRITE = 2
PROT_EXEC = 4
// ../../lib/wasi-libc/expected/wasm32-wasi/predefined-macros.txt
F_GETFL = 3
F_SETFL = 4
// ../../lib/wasi-libc/libc-top-half/musl/arch/generic/bits/ioctl.h
TIOCSPGRP = 0x5410
)
// These values are needed as a stub until Go supports WASI as a full target.
// The constant values don't have a meaning and don't correspond to anything
// real.
const (
_ = iota
SYS_FCNTL
SYS_FCNTL64
SYS_FSTATAT64
SYS_IOCTL
SYS_MKDIRAT
SYS_OPENAT
SYS_READLINKAT
SYS_UNLINKAT
SYS_WAITID
PATH_MAX = 4096
)
func getErrno() error {
// libcErrno is the errno from wasi-libc for wasip1 and the errno for libc_wasip2 for wasip2
return libcErrno
}
func (e Errno) Is(target error) bool {
switch target.Error() {
case "permission denied":
return e == EACCES || e == EPERM || e == ENOTCAPABLE // ENOTCAPABLE is unique in WASI
case "file already exists":
return e == EEXIST || e == ENOTEMPTY
case "file does not exist":
return e == ENOENT
}
return false
}
// https://github.com/WebAssembly/wasi-libc/blob/main/libc-bottom-half/headers/public/__errno.h
const (
E2BIG Errno = 1 /* Argument list too long */
EACCES Errno = 2 /* Permission denied */
EADDRINUSE Errno = 3 /* Address already in use */
EADDRNOTAVAIL Errno = 4 /* Address not available */
EAFNOSUPPORT Errno = 5 /* Address family not supported by protocol family */
EAGAIN Errno = 6 /* Try again */
EWOULDBLOCK Errno = EAGAIN /* Operation would block */
EALREADY Errno = 7 /* Socket already connected */
EBADF Errno = 8 /* Bad file number */
EBADMSG Errno = 9 /* Trying to read unreadable message */
EBUSY Errno = 10 /* Device or resource busy */
ECANCELED Errno = 11 /* Operation canceled. */
ECHILD Errno = 12 /* No child processes */
ECONNABORTED Errno = 13 /* Connection aborted */
ECONNREFUSED Errno = 14 /* Connection refused */
ECONNRESET Errno = 15 /* Connection reset by peer */
EDEADLK Errno = 16 /* Deadlock condition */
EDESTADDRREQ Errno = 17 /* Destination address required */
EDOM Errno = 18 /* Math arg out of domain of func */
EDQUOT Errno = 19 /* Quota exceeded */
EEXIST Errno = 20 /* File exists */
EFAULT Errno = 21 /* Bad address */
EFBIG Errno = 22 /* File too large */
EHOSTUNREACH Errno = 23 /* Host is unreachable */
EIDRM Errno = 24 /* Identifier removed */
EILSEQ Errno = 25
EINPROGRESS Errno = 26 /* Connection already in progress */
EINTR Errno = 27 /* Interrupted system call */
EINVAL Errno = 28 /* Invalid argument */
EIO Errno = 29 /* I/O error */
EISCONN Errno = 30 /* Socket is already connected */
EISDIR Errno = 31 /* Is a directory */
ELOOP Errno = 32 /* Too many symbolic links */
EMFILE Errno = 33 /* Too many open files */
EMLINK Errno = 34 /* Too many links */
EMSGSIZE Errno = 35 /* Message too long */
EMULTIHOP Errno = 36 /* Multihop attempted */
ENAMETOOLONG Errno = 37 /* File name too long */
ENETDOWN Errno = 38 /* Network interface is not configured */
ENETRESET Errno = 39
ENETUNREACH Errno = 40 /* Network is unreachable */
ENFILE Errno = 41 /* File table overflow */
ENOBUFS Errno = 42 /* No buffer space available */
ENODEV Errno = 43 /* No such device */
ENOENT Errno = 44 /* No such file or directory */
ENOEXEC Errno = 45 /* Exec format error */
ENOLCK Errno = 46 /* No record locks available */
ENOLINK Errno = 47 /* The link has been severed */
ENOMEM Errno = 48 /* Out of memory */
ENOMSG Errno = 49 /* No message of desired type */
ENOPROTOOPT Errno = 50 /* Protocol not available */
ENOSPC Errno = 51 /* No space left on device */
ENOSYS Errno = 52 /* Function not implemented */
ENOTCONN Errno = 53 /* Socket is not connected */
ENOTDIR Errno = 54 /* Not a directory */
ENOTEMPTY Errno = 55 /* Directory not empty */
ENOTRECOVERABLE Errno = 56 /* State not recoverable */
ENOTSOCK Errno = 57 /* Socket operation on non-socket */
ESOCKTNOSUPPORT Errno = 58 /* Socket type not supported */
EOPNOTSUPP Errno = 58 /* Operation not supported on transport endpoint */
ENOTSUP Errno = EOPNOTSUPP /* Not supported */
ENOTTY Errno = 59 /* Not a typewriter */
ENXIO Errno = 60 /* No such device or address */
EOVERFLOW Errno = 61 /* Value too large for defined data type */
EPERM Errno = 63 /* Operation not permitted */
EPIPE Errno = 64 /* Broken pipe */
EPROTO Errno = 65 /* Protocol error */
EPROTONOSUPPORT Errno = 66 /* Unknown protocol */
EPROTOTYPE Errno = 67 /* Protocol wrong type for socket */
ERANGE Errno = 68 /* Math result not representable */
EROFS Errno = 69 /* Read-only file system */
ESPIPE Errno = 70 /* Illegal seek */
ESRCH Errno = 71 /* No such process */
ESTALE Errno = 72
ETIMEDOUT Errno = 73 /* Connection timed out */
ETXTBSY Errno = 74 /* Text file busy */
EXDEV Errno = 75 /* Cross-device link */
ENOTCAPABLE Errno = 76 /* Extension: Capabilities insufficient. */
EWASIERROR Errno = 255 /* Unknown WASI error */
)
// TODO(ydnar): remove Timespec for WASI Preview 2 (seconds is uint64).
//
// https://github.com/WebAssembly/wasi-libc/blob/main/libc-bottom-half/headers/public/__struct_timespec.h
type Timespec struct {
Sec int32
Nsec int64
}
// Unix returns the time stored in ts as seconds plus nanoseconds.
func (ts *Timespec) Unix() (sec int64, nsec int64) {
return int64(ts.Sec), int64(ts.Nsec)
}
// https://github.com/WebAssembly/wasi-libc/blob/main/libc-bottom-half/headers/public/__struct_stat.h
// https://github.com/WebAssembly/wasi-libc/blob/main/libc-bottom-half/headers/public/__typedef_ino_t.h
// etc.
type Stat_t struct {
Dev uint64
Ino uint64
Nlink uint64
Mode uint32
Uid uint32
Gid uint32
Pad_cgo_0 [4]byte
Rdev uint64
Size int64
Blksize int32
Blocks int64
Atim Timespec
Mtim Timespec
Ctim Timespec
Qspare [3]int64
}
// https://github.com/WebAssembly/wasi-libc/blob/main/libc-top-half/musl/include/sys/stat.h
const (
S_IFBLK = 0x6000
S_IFCHR = 0x2000
S_IFDIR = 0x4000
S_IFIFO = 0x1000
S_IFLNK = 0xa000
S_IFMT = 0xf000
S_IFREG = 0x8000
S_IFSOCK = 0xc000
S_IREAD = 0x100
S_IRGRP = 0x20
S_IROTH = 0x4
S_IRUSR = 0x100
S_IRWXG = 0x38
S_IRWXO = 0x7
S_IRWXU = 0x1c0
S_ISGID = 0x400
S_ISUID = 0x800
S_ISVTX = 0x200
S_IWGRP = 0x10
S_IWOTH = 0x2
S_IWRITE = 0x80
S_IWUSR = 0x80
S_IXGRP = 0x8
S_IXOTH = 0x1
S_IXUSR = 0x40
)
// https://github.com/WebAssembly/wasi-libc/blob/main/libc-bottom-half/headers/public/__header_dirent.h
const (
DT_BLK = __WASI_FILETYPE_BLOCK_DEVICE
DT_CHR = __WASI_FILETYPE_CHARACTER_DEVICE
DT_DIR = __WASI_FILETYPE_DIRECTORY
DT_FIFO = __WASI_FILETYPE_SOCKET_STREAM
DT_LNK = __WASI_FILETYPE_SYMBOLIC_LINK
DT_REG = __WASI_FILETYPE_REGULAR_FILE
DT_UNKNOWN = __WASI_FILETYPE_UNKNOWN
)
// Dirent is returned by pointer from Readdir to iterate over directory entries.
//
// The pointer is managed by wasi-libc and is only valid until the next call to
// Readdir or Fdclosedir.
//
// https://github.com/WebAssembly/wasi-libc/blob/main/libc-bottom-half/headers/public/__struct_dirent.h
type Dirent struct {
Ino uint64
Type uint8
}
func (dirent *Dirent) Name() []byte {
// The dirent C struct uses a flexible array member to indicate that the
// directory name is laid out in memory right after the struct data:
//
// struct dirent {
// ino_t d_ino;
// unsigned char d_type;
// char d_name[];
// };
name := (*[PATH_MAX]byte)(unsafe.Add(unsafe.Pointer(dirent), 9))
for i, c := range name {
if c == 0 {
return name[:i:i]
}
}
return name[:]
}
func Fdopendir(fd int) (dir uintptr, err error) {
d := libc_fdopendir(int32(fd))
if d == nil {
err = getErrno()
}
return uintptr(d), err
}
func Fdclosedir(dir uintptr) (err error) {
// Unlike on other unix platform where only closedir exists, wasi-libc has
// fdclosedir which releases resources and returns the file descriptor but
// does not close it. This is useful for us since we want to be able to keep
// using it.
n := libc_fdclosedir(unsafe.Pointer(dir))
if n < 0 {
err = getErrno()
}
return
}
func Readdir(dir uintptr) (dirent *Dirent, err error) {
// There might be a leftover errno value in the global variable, so we have
// to clear it before calling readdir because we cannot know whether a nil
// return means that we reached EOF or that an error occurred.
libcErrno = 0
dirent = libc_readdir(unsafe.Pointer(dir))
if dirent == nil && libcErrno != 0 {
err = getErrno()
}
return
}
func Stat(path string, p *Stat_t) (err error) {
data := cstring(path)
n := libc_stat(&data[0], unsafe.Pointer(p))
if n < 0 {
err = getErrno()
}
return
}
func Fstat(fd int, p *Stat_t) (err error) {
n := libc_fstat(int32(fd), unsafe.Pointer(p))
if n < 0 {
err = getErrno()
}
return
}
func Lstat(path string, p *Stat_t) (err error) {
data := cstring(path)
n := libc_lstat(&data[0], unsafe.Pointer(p))
if n < 0 {
err = getErrno()
}
return
}
func Pipe2(p []int, flags int) (err error) {
return ENOSYS // TODO
}
func Chmod(path string, mode uint32) (err error) {
// wasi does not have chmod, but there are tests that validate that calling
// os.Chmod does not error (e.g. io/fs.TestIssue51617).
//
// We make a call to Lstat instead so we detect conditions like the path not
// existing, but we don't honnor the request to modify the file permissions.
stat := Stat_t{}
return Lstat(path, &stat)
}
// TODO: should this return runtime.wasmPageSize?
func Getpagesize() int {
return libc_getpagesize()
}
type Utsname struct {
Sysname [65]int8
Nodename [65]int8
Release [65]int8
Version [65]int8
Machine [65]int8
Domainname [65]int8
}
//go:linkname faccessat syscall.Faccessat
func faccessat(dirfd int, path string, mode uint32, flags int) (err error) {
return ENOSYS
}
// Stub Utsname, needed because WASI pretends to be linux/arm.
func Uname(buf *Utsname) (err error)
type RawSockaddrInet4 struct {
// stub
}
type RawSockaddrInet6 struct {
// stub
}
func RandomGet(b []byte) error {
if len(b) > 0 {
libc_arc4random_buf(unsafe.Pointer(&b[0]), uint(len(b)))
}
return nil
}
// This is a stub, it is not functional.
func Syscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
// This is a stub, it is not functional.
func Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
// int getpagesize(void);
//
//export getpagesize
func libc_getpagesize() int
// int stat(const char *path, struct stat * buf);
//
//export stat
func libc_stat(pathname *byte, ptr unsafe.Pointer) int32
// int fstat(int fd, struct stat * buf);
//
//export fstat
func libc_fstat(fd int32, ptr unsafe.Pointer) int32
// int lstat(const char *path, struct stat * buf);
//
//export lstat
func libc_lstat(pathname *byte, ptr unsafe.Pointer) int32
// int open(const char *pathname, int flags, mode_t mode);
//
//export open
func libc_open(pathname *byte, flags int32, mode uint32) int32
// DIR *fdopendir(int);
//
//export fdopendir
func libc_fdopendir(fd int32) unsafe.Pointer
// int fdclosedir(DIR *);
//
//export fdclosedir
func libc_fdclosedir(unsafe.Pointer) int32
// struct dirent *readdir(DIR *);
//
//export readdir
func libc_readdir(unsafe.Pointer) *Dirent
// void arc4random_buf(void *buf, size_t buflen);
//
//export arc4random_buf
func libc_arc4random_buf(buf unsafe.Pointer, buflen uint)