github.com/wasilibs/wazerox@v0.0.0-20240124024944-4923be63ab5f/experimental/sys/errno.go (about)

     1  package sys
     2  
     3  import "strconv"
     4  
     5  // Errno is a subset of POSIX errno used by wazero interfaces. Zero is not an
     6  // error. Other values should not be interpreted numerically, rather by constants
     7  // prefixed with 'E'.
     8  //
     9  // See https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/errno.h.html
    10  type Errno uint16
    11  
    12  // ^-- Note: This will eventually move to the public /sys package. It is
    13  // experimental until we audit the socket related APIs to ensure we have all
    14  // the Errno it returns, and we export fs.FS. This is not in /internal/sys as
    15  // that would introduce a package cycle.
    16  
    17  // This is a subset of errors to reduce implementation burden. `wasip1` defines
    18  // almost all POSIX error numbers, but not all are used in practice. wazero
    19  // will add ones needed in POSIX order, as needed by functions that explicitly
    20  // document returning them.
    21  //
    22  // https://github.com/WebAssembly/WASI/blob/snapshot-01/phases/snapshot/docs.md#-errno-enumu16
    23  const (
    24  	EACCES Errno = iota + 1
    25  	EAGAIN
    26  	EBADF
    27  	EEXIST
    28  	EFAULT
    29  	EINTR
    30  	EINVAL
    31  	EIO
    32  	EISDIR
    33  	ELOOP
    34  	ENAMETOOLONG
    35  	ENOENT
    36  	ENOSYS
    37  	ENOTDIR
    38  	ERANGE
    39  	ENOTEMPTY
    40  	ENOTSOCK
    41  	ENOTSUP
    42  	EPERM
    43  	EROFS
    44  
    45  	// NOTE ENOTCAPABLE is defined in wasip1, but not in POSIX. wasi-libc
    46  	// converts it to EBADF, ESPIPE or EINVAL depending on the call site.
    47  	// It isn't known if compilers who don't use ENOTCAPABLE would crash on it.
    48  )
    49  
    50  // Error implements error
    51  func (e Errno) Error() string {
    52  	switch e {
    53  	case 0: // not an error
    54  		return "success"
    55  	case EACCES:
    56  		return "permission denied"
    57  	case EAGAIN:
    58  		return "resource unavailable, try again"
    59  	case EBADF:
    60  		return "bad file descriptor"
    61  	case EEXIST:
    62  		return "file exists"
    63  	case EFAULT:
    64  		return "bad address"
    65  	case EINTR:
    66  		return "interrupted function"
    67  	case EINVAL:
    68  		return "invalid argument"
    69  	case EIO:
    70  		return "input/output error"
    71  	case EISDIR:
    72  		return "is a directory"
    73  	case ELOOP:
    74  		return "too many levels of symbolic links"
    75  	case ENAMETOOLONG:
    76  		return "filename too long"
    77  	case ENOENT:
    78  		return "no such file or directory"
    79  	case ENOSYS:
    80  		return "functionality not supported"
    81  	case ENOTDIR:
    82  		return "not a directory or a symbolic link to a directory"
    83  	case ERANGE:
    84  		return "result too large"
    85  	case ENOTEMPTY:
    86  		return "directory not empty"
    87  	case ENOTSOCK:
    88  		return "not a socket"
    89  	case ENOTSUP:
    90  		return "not supported (may be the same value as [EOPNOTSUPP])"
    91  	case EPERM:
    92  		return "operation not permitted"
    93  	case EROFS:
    94  		return "read-only file system"
    95  	default:
    96  		return "Errno(" + strconv.Itoa(int(e)) + ")"
    97  	}
    98  }