From 554fd8c5195424bdbcabf5de30fdc183aba391bd Mon Sep 17 00:00:00 2001 From: upstream source tree Date: Sun, 15 Mar 2015 20:14:05 -0400 Subject: obtained gcc-4.6.4.tar.bz2 from upstream website; verified gcc-4.6.4.tar.bz2.sig; imported gcc-4.6.4 source tree from verified upstream tarball. downloading a git-generated archive based on the 'upstream' tag should provide you with a source tree that is binary identical to the one extracted from the above tarball. if you have obtained the source via the command 'git clone', however, do note that line-endings of files in your working directory might differ from line-endings of the respective files in the upstream repository. --- libgo/go/os/file.go | 438 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 438 insertions(+) create mode 100644 libgo/go/os/file.go (limited to 'libgo/go/os/file.go') diff --git a/libgo/go/os/file.go b/libgo/go/os/file.go new file mode 100644 index 000000000..3f73f1dff --- /dev/null +++ b/libgo/go/os/file.go @@ -0,0 +1,438 @@ +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// The os package provides a platform-independent interface to operating +// system functionality. The design is Unix-like. +package os + +import ( + "runtime" + "syscall" +) + +// File represents an open file descriptor. +type File struct { + fd int + name string + dirinfo *dirInfo // nil unless directory being read + nepipe int // number of consecutive EPIPE in Write +} + +// Fd returns the integer Unix file descriptor referencing the open file. +func (file *File) Fd() int { return file.fd } + +// Name returns the name of the file as presented to Open. +func (file *File) Name() string { return file.name } + +// NewFile returns a new File with the given file descriptor and name. +func NewFile(fd int, name string) *File { + if fd < 0 { + return nil + } + f := &File{fd, name, nil, 0} + runtime.SetFinalizer(f, (*File).Close) + return f +} + +// Stdin, Stdout, and Stderr are open Files pointing to the standard input, +// standard output, and standard error file descriptors. +var ( + Stdin = NewFile(syscall.Stdin, "/dev/stdin") + Stdout = NewFile(syscall.Stdout, "/dev/stdout") + Stderr = NewFile(syscall.Stderr, "/dev/stderr") +) + +// Flags to Open wrapping those of the underlying system. Not all flags +// may be implemented on a given system. +const ( + O_RDONLY int = syscall.O_RDONLY // open the file read-only. + O_WRONLY int = syscall.O_WRONLY // open the file write-only. + O_RDWR int = syscall.O_RDWR // open the file read-write. + O_APPEND int = syscall.O_APPEND // append data to the file when writing. + O_ASYNC int = syscall.O_ASYNC // generate a signal when I/O is available. + O_CREAT int = syscall.O_CREAT // create a new file if none exists. + O_EXCL int = syscall.O_EXCL // used with O_CREAT, file must not exist + O_NOCTTY int = syscall.O_NOCTTY // do not make file the controlling tty. + O_NONBLOCK int = syscall.O_NONBLOCK // open in non-blocking mode. + O_NDELAY int = O_NONBLOCK // synonym for O_NONBLOCK + O_SYNC int = syscall.O_SYNC // open for synchronous I/O. + O_TRUNC int = syscall.O_TRUNC // if possible, truncate file when opened. + O_CREATE int = O_CREAT // create a new file if none exists. +) + +type eofError int + +func (eofError) String() string { return "EOF" } + +// EOF is the Error returned by Read when no more input is available. +// Functions should return EOF only to signal a graceful end of input. +// If the EOF occurs unexpectedly in a structured data stream, +// the appropriate error is either io.ErrUnexpectedEOF or some other error +// giving more detail. +var EOF Error = eofError(0) + +// Read reads up to len(b) bytes from the File. +// It returns the number of bytes read and an Error, if any. +// EOF is signaled by a zero count with err set to EOF. +func (file *File) Read(b []byte) (n int, err Error) { + if file == nil { + return 0, EINVAL + } + n, e := syscall.Read(file.fd, b) + if n < 0 { + n = 0 + } + if n == 0 && e == 0 { + return 0, EOF + } + if e != 0 { + err = &PathError{"read", file.name, Errno(e)} + } + return n, err +} + +// ReadAt reads len(b) bytes from the File starting at byte offset off. +// It returns the number of bytes read and the Error, if any. +// EOF is signaled by a zero count with err set to EOF. +// ReadAt always returns a non-nil Error when n != len(b). +func (file *File) ReadAt(b []byte, off int64) (n int, err Error) { + if file == nil { + return 0, EINVAL + } + for len(b) > 0 { + m, e := syscall.Pread(file.fd, b, off) + if m == 0 && e == 0 { + return n, EOF + } + if e != 0 { + err = &PathError{"read", file.name, Errno(e)} + break + } + n += m + b = b[m:] + off += int64(m) + } + return +} + +// Write writes len(b) bytes to the File. +// It returns the number of bytes written and an Error, if any. +// Write returns a non-nil Error when n != len(b). +func (file *File) Write(b []byte) (n int, err Error) { + if file == nil { + return 0, EINVAL + } + n, e := syscall.Write(file.fd, b) + if n < 0 { + n = 0 + } + if e == syscall.EPIPE { + file.nepipe++ + if file.nepipe >= 10 { + Exit(syscall.EPIPE) + } + } else { + file.nepipe = 0 + } + if e != 0 { + err = &PathError{"write", file.name, Errno(e)} + } + return n, err +} + +// WriteAt writes len(b) bytes to the File starting at byte offset off. +// It returns the number of bytes written and an Error, if any. +// WriteAt returns a non-nil Error when n != len(b). +func (file *File) WriteAt(b []byte, off int64) (n int, err Error) { + if file == nil { + return 0, EINVAL + } + for len(b) > 0 { + m, e := syscall.Pwrite(file.fd, b, off) + if e != 0 { + err = &PathError{"write", file.name, Errno(e)} + break + } + n += m + b = b[m:] + off += int64(m) + } + return +} + +// Seek sets the offset for the next Read or Write on file to offset, interpreted +// according to whence: 0 means relative to the origin of the file, 1 means +// relative to the current offset, and 2 means relative to the end. +// It returns the new offset and an Error, if any. +func (file *File) Seek(offset int64, whence int) (ret int64, err Error) { + r, e := syscall.Seek(file.fd, offset, whence) + if e == 0 && file.dirinfo != nil && r != 0 { + e = syscall.EISDIR + } + if e != 0 { + return 0, &PathError{"seek", file.name, Errno(e)} + } + return r, nil +} + +// WriteString is like Write, but writes the contents of string s rather than +// an array of bytes. +func (file *File) WriteString(s string) (ret int, err Error) { + if file == nil { + return 0, EINVAL + } + b := syscall.StringByteSlice(s) + b = b[0 : len(b)-1] + return file.Write(b) +} + +// Pipe returns a connected pair of Files; reads from r return bytes written to w. +// It returns the files and an Error, if any. +func Pipe() (r *File, w *File, err Error) { + var p [2]int + + // See ../syscall/exec.go for description of lock. + syscall.ForkLock.RLock() + e := syscall.Pipe(p[0:]) + if e != 0 { + syscall.ForkLock.RUnlock() + return nil, nil, NewSyscallError("pipe", e) + } + syscall.CloseOnExec(p[0]) + syscall.CloseOnExec(p[1]) + syscall.ForkLock.RUnlock() + + return NewFile(p[0], "|0"), NewFile(p[1], "|1"), nil +} + +// Mkdir creates a new directory with the specified name and permission bits. +// It returns an error, if any. +func Mkdir(name string, perm uint32) Error { + e := syscall.Mkdir(name, perm) + if e != 0 { + return &PathError{"mkdir", name, Errno(e)} + } + return nil +} + +// Stat returns a FileInfo structure describing the named file and an error, if any. +// If name names a valid symbolic link, the returned FileInfo describes +// the file pointed at by the link and has fi.FollowedSymlink set to true. +// If name names an invalid symbolic link, the returned FileInfo describes +// the link itself and has fi.FollowedSymlink set to false. +func Stat(name string) (fi *FileInfo, err Error) { + var lstat, stat syscall.Stat_t + e := syscall.Lstat(name, &lstat) + if e != 0 { + return nil, &PathError{"stat", name, Errno(e)} + } + statp := &lstat + if lstat.Mode&syscall.S_IFMT == syscall.S_IFLNK { + e := syscall.Stat(name, &stat) + if e == 0 { + statp = &stat + } + } + return fileInfoFromStat(name, new(FileInfo), &lstat, statp), nil +} + +// Lstat returns the FileInfo structure describing the named file and an +// error, if any. If the file is a symbolic link, the returned FileInfo +// describes the symbolic link. Lstat makes no attempt to follow the link. +func Lstat(name string) (fi *FileInfo, err Error) { + var stat syscall.Stat_t + e := syscall.Lstat(name, &stat) + if e != 0 { + return nil, &PathError{"lstat", name, Errno(e)} + } + return fileInfoFromStat(name, new(FileInfo), &stat, &stat), nil +} + +// Chdir changes the current working directory to the named directory. +func Chdir(dir string) Error { + if e := syscall.Chdir(dir); e != 0 { + return &PathError{"chdir", dir, Errno(e)} + } + return nil +} + +// Chdir changes the current working directory to the file, +// which must be a directory. +func (f *File) Chdir() Error { + if e := syscall.Fchdir(f.fd); e != 0 { + return &PathError{"chdir", f.name, Errno(e)} + } + return nil +} + +// Remove removes the named file or directory. +func Remove(name string) Error { + // System call interface forces us to know + // whether name is a file or directory. + // Try both: it is cheaper on average than + // doing a Stat plus the right one. + e := syscall.Unlink(name) + if e == 0 { + return nil + } + e1 := syscall.Rmdir(name) + if e1 == 0 { + return nil + } + + // Both failed: figure out which error to return. + // OS X and Linux differ on whether unlink(dir) + // returns EISDIR, so can't use that. However, + // both agree that rmdir(file) returns ENOTDIR, + // so we can use that to decide which error is real. + // Rmdir might also return ENOTDIR if given a bad + // file path, like /etc/passwd/foo, but in that case, + // both errors will be ENOTDIR, so it's okay to + // use the error from unlink. + // For windows syscall.ENOTDIR is set + // to syscall.ERROR_DIRECTORY, hopefully it should + // do the trick. + if e1 != syscall.ENOTDIR { + e = e1 + } + return &PathError{"remove", name, Errno(e)} +} + +// LinkError records an error during a link or symlink or rename +// system call and the paths that caused it. +type LinkError struct { + Op string + Old string + New string + Error Error +} + +func (e *LinkError) String() string { + return e.Op + " " + e.Old + " " + e.New + ": " + e.Error.String() +} + +// Link creates a hard link. +func Link(oldname, newname string) Error { + e := syscall.Link(oldname, newname) + if e != 0 { + return &LinkError{"link", oldname, newname, Errno(e)} + } + return nil +} + +// Symlink creates a symbolic link. +func Symlink(oldname, newname string) Error { + e := syscall.Symlink(oldname, newname) + if e != 0 { + return &LinkError{"symlink", oldname, newname, Errno(e)} + } + return nil +} + +// Readlink reads the contents of a symbolic link: the destination of +// the link. It returns the contents and an Error, if any. +func Readlink(name string) (string, Error) { + for len := 128; ; len *= 2 { + b := make([]byte, len) + n, e := syscall.Readlink(name, b) + if e != 0 { + return "", &PathError{"readlink", name, Errno(e)} + } + if n < len { + return string(b[0:n]), nil + } + } + // Silence 6g. + return "", nil +} + +// Rename renames a file. +func Rename(oldname, newname string) Error { + e := syscall.Rename(oldname, newname) + if e != 0 { + return &LinkError{"rename", oldname, newname, Errno(e)} + } + return nil +} + +// Chmod changes the mode of the named file to mode. +// If the file is a symbolic link, it changes the mode of the link's target. +func Chmod(name string, mode uint32) Error { + if e := syscall.Chmod(name, mode); e != 0 { + return &PathError{"chmod", name, Errno(e)} + } + return nil +} + +// Chmod changes the mode of the file to mode. +func (f *File) Chmod(mode uint32) Error { + if e := syscall.Fchmod(f.fd, mode); e != 0 { + return &PathError{"chmod", f.name, Errno(e)} + } + return nil +} + +// Chown changes the numeric uid and gid of the named file. +// If the file is a symbolic link, it changes the uid and gid of the link's target. +func Chown(name string, uid, gid int) Error { + if e := syscall.Chown(name, uid, gid); e != 0 { + return &PathError{"chown", name, Errno(e)} + } + return nil +} + +// Lchown changes the numeric uid and gid of the named file. +// If the file is a symbolic link, it changes the uid and gid of the link itself. +func Lchown(name string, uid, gid int) Error { + if e := syscall.Lchown(name, uid, gid); e != 0 { + return &PathError{"lchown", name, Errno(e)} + } + return nil +} + +// Chown changes the numeric uid and gid of the named file. +func (f *File) Chown(uid, gid int) Error { + if e := syscall.Fchown(f.fd, uid, gid); e != 0 { + return &PathError{"chown", f.name, Errno(e)} + } + return nil +} + +// Truncate changes the size of the file. +// It does not change the I/O offset. +func (f *File) Truncate(size int64) Error { + if e := syscall.Ftruncate(f.fd, size); e != 0 { + return &PathError{"truncate", f.name, Errno(e)} + } + return nil +} + +// Sync commits the current contents of the file to stable storage. +// Typically, this means flushing the file system's in-memory copy +// of recently written data to disk. +func (file *File) Sync() (err Error) { + if file == nil { + return EINVAL + } + if e := syscall.Fsync(file.fd); e != 0 { + return NewSyscallError("fsync", e) + } + return nil +} + +// Chtimes changes the access and modification times of the named +// file, similar to the Unix utime() or utimes() functions. +// +// The argument times are in nanoseconds, although the underlying +// filesystem may truncate or round the values to a more +// coarse time unit. +func Chtimes(name string, atime_ns int64, mtime_ns int64) Error { + var utimes [2]syscall.Timeval + utimes[0] = syscall.NsecToTimeval(atime_ns) + utimes[1] = syscall.NsecToTimeval(mtime_ns) + if e := syscall.Utimes(name, utimes[0:]); e != 0 { + return &PathError{"chtimes", name, Errno(e)} + } + return nil +} -- cgit v1.2.3