Imported Upstream version 2011.04.13upstream/2011.04.13

1 files changed, 36 insertions, 241 deletions

diff --git a/src/pkg/os/file.go b/src/pkg/os/file.go
index 3f73f1dff..3aad80234 100644
--- a/src/pkg/os/file.go
+++ b/src/pkg/os/file.go
@@ -51,14 +51,20 @@ const (
 	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_CREATE   int = syscall.O_CREAT    // create a new file if none exists.
+	O_EXCL     int = syscall.O_EXCL     // used with O_CREATE, 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.
+)
+
+// Seek whence values.
+const (
+	SEEK_SET int = 0 // seek relative to the origin of the file
+	SEEK_CUR int = 1 // seek relative to the current offset
+	SEEK_END int = 2 // seek relative to the end
 )
 
 type eofError int
@@ -83,10 +89,10 @@ func (file *File) Read(b []byte) (n int, err Error) {
 	if n < 0 {
 		n = 0
 	}
-	if n == 0 && e == 0 {
+	if n == 0 && !iserror(e) {
 		return 0, EOF
 	}
-	if e != 0 {
+	if iserror(e) {
 		err = &PathError{"read", file.name, Errno(e)}
 	}
 	return n, err
@@ -102,10 +108,10 @@ func (file *File) ReadAt(b []byte, off int64) (n int, err Error) {
 	}
 	for len(b) > 0 {
 		m, e := syscall.Pread(file.fd, b, off)
-		if m == 0 && e == 0 {
+		if m == 0 && !iserror(e) {
 			return n, EOF
 		}
-		if e != 0 {
+		if iserror(e) {
 			err = &PathError{"read", file.name, Errno(e)}
 			break
 		}
@@ -127,15 +133,10 @@ func (file *File) Write(b []byte) (n int, err Error) {
 	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 {
+
+	epipecheck(file, e)
+
+	if iserror(e) {
 		err = &PathError{"write", file.name, Errno(e)}
 	}
 	return n, err
@@ -150,7 +151,7 @@ func (file *File) WriteAt(b []byte, off int64) (n int, err Error) {
 	}
 	for len(b) > 0 {
 		m, e := syscall.Pwrite(file.fd, b, off)
-		if e != 0 {
+		if iserror(e) {
 			err = &PathError{"write", file.name, Errno(e)}
 			break
 		}
@@ -167,10 +168,10 @@ func (file *File) WriteAt(b []byte, off int64) (n int, err Error) {
 // 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 {
+	if !iserror(e) && file.dirinfo != nil && r != 0 {
 		e = syscall.EISDIR
 	}
-	if e != 0 {
+	if iserror(e) {
 		return 0, &PathError{"seek", file.name, Errno(e)}
 	}
 	return r, nil
@@ -187,71 +188,19 @@ func (file *File) WriteString(s string) (ret int, err Error) {
 	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 {
+	if iserror(e) {
 		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 {
+	if e := syscall.Chdir(dir); iserror(e) {
 		return &PathError{"chdir", dir, Errno(e)}
 	}
 	return nil
@@ -260,179 +209,25 @@ func Chdir(dir string) Error {
 // 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 {
+	if e := syscall.Fchdir(f.fd); iserror(e) {
 		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()
+// Open opens the named file for reading.  If successful, methods on
+// the returned file can be used for reading; the associated file
+// descriptor has mode O_RDONLY.
+// It returns the File and an Error, if any.
+func Open(name string) (file *File, err Error) {
+	return OpenFile(name, O_RDONLY, 0)
 }
 
-// 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
+// Create creates the named file mode 0666 (before umask), truncating
+// it if it already exists.  If successful, methods on the returned
+// File can be used for I/O; the associated file descriptor has mode
+// O_RDWR.
+// It returns the File and an Error, if any.
+func Create(name string) (file *File, err Error) {
+	return OpenFile(name, O_RDWR|O_CREATE|O_TRUNC, 0666)
 }