add Getwd, Fchdir, tests
R=r
DELTA=215 (186 added, 0 deleted, 29 changed)
OCL=28968
CL=28995
diff --git a/src/lib/os/Makefile b/src/lib/os/Makefile
index 02863cc..50a06d9 100644
--- a/src/lib/os/Makefile
+++ b/src/lib/os/Makefile
@@ -3,7 +3,7 @@
# license that can be found in the LICENSE file.
# DO NOT EDIT. Automatically generated by gobuild.
-# gobuild -m dir_${GOARCH}_${GOOS}.go env.go error.go file.go path.go proc_${GOOS}.go stat_${GOARCH}_${GOOS}.go time.go types.go exec.go user.go >Makefile
+# gobuild -m dir_${GOARCH}_${GOOS}.go env.go error.go file.go path.go proc_${GOOS}.go stat_${GOARCH}_${GOOS}.go time.go types.go exec.go user.go getwd.go >Makefile
D=
@@ -56,6 +56,7 @@
O4=\
dir_$(GOARCH)_$(GOOS).$O\
exec.$O\
+ getwd.$O\
path.$O\
@@ -75,7 +76,7 @@
rm -f $(O3)
a4: $(O4)
- $(AR) grc _obj$D/os.a dir_$(GOARCH)_$(GOOS).$O exec.$O path.$O
+ $(AR) grc _obj$D/os.a dir_$(GOARCH)_$(GOOS).$O exec.$O getwd.$O path.$O
rm -f $(O4)
diff --git a/src/lib/os/error.go b/src/lib/os/error.go
index 53f58c9..7784656 100644
--- a/src/lib/os/error.go
+++ b/src/lib/os/error.go
@@ -79,5 +79,6 @@
ERANGE Error = Errno(syscall.ERANGE);
EADDRINUSE Error = Errno(syscall.EADDRINUSE);
ECONNREFUSED Error = Errno(syscall.ECONNREFUSED);
+ ENAMETOOLONG Error = Errno(syscall.ENAMETOOLONG);
)
diff --git a/src/lib/os/file.go b/src/lib/os/file.go
index d658073..7aa6632 100644
--- a/src/lib/os/file.go
+++ b/src/lib/os/file.go
@@ -284,6 +284,13 @@
return ErrnoToError(e);
}
+// Chdir changes the current working directory to the file,
+// which must be a directory.
+func (f *File) Chdir() Error {
+ r, e := syscall.Fchdir(f.fd);
+ return ErrnoToError(e);
+}
+
// Remove removes the named file or directory.
func Remove(name string) Error {
// System call interface forces us to know
diff --git a/src/lib/os/getwd.go b/src/lib/os/getwd.go
new file mode 100644
index 0000000..2d7b754
--- /dev/null
+++ b/src/lib/os/getwd.go
@@ -0,0 +1,94 @@
+// 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.
+
+package os
+
+import (
+ "os";
+ "syscall"
+)
+
+// Getwd returns a rooted path name corresponding to the
+// current directory. If the current directory can be
+// reached via multiple paths (due to symbolic links),
+// Getwd may return any one of them.
+func Getwd() (string, Error) {
+ // If the operating system provides a Getwd call, use it.
+ if syscall.ImplementsGetwd {
+ s, e := syscall.Getwd();
+ return s, ErrnoToError(e);
+ }
+
+ // Otherwise, we're trying to find our way back to ".".
+ dot, err := Stat(".");
+ if err != nil {
+ return "", err;
+ }
+
+ // Clumsy but widespread kludge:
+ // if $PWD is set and matches ".", use it.
+ pwd, _ := Getenv("PWD");
+ if len(pwd) > 0 && pwd[0] == '/' {
+ d, err := Stat(pwd);
+ if err == nil && d.Dev == dot.Dev && d.Ino == dot.Ino {
+ return pwd, nil
+ }
+ }
+
+ // Root is a special case because it has no parent
+ // and ends in a slash.
+ root, err := Stat("/");
+ if err != nil {
+ // Can't stat root - no hope.
+ return "", err;
+ }
+ if root.Dev == dot.Dev && root.Ino == dot.Ino {
+ return "/", nil
+ }
+
+ // General algorithm: find name in parent
+ // and then find name of parent. Each iteration
+ // adds /name to the beginning of pwd.
+ elem := make([]string, 0, 16);
+ pwd = "";
+ for parent := "..";; parent = "../" + parent {
+ if len(parent) >= 1024 { // Sanity check
+ return "", ENAMETOOLONG;
+ }
+ fd, err := Open(parent, O_RDONLY, 0);
+ if err != nil {
+ return "", err;
+ }
+
+ for {
+ names, err := fd.Readdirnames(100);
+ if err != nil {
+ fd.Close();
+ return "", err;
+ }
+ for i, name := range names {
+ d, err := Lstat(parent + "/" + name);
+ if d.Dev == dot.Dev && d.Ino == dot.Ino {
+ pwd = "/" + name + pwd;
+ goto Found;
+ }
+ }
+ }
+ fd.Close();
+ return "", ENOENT;
+
+ Found:
+ pd, err := fd.Stat();
+ if err != nil {
+ return "", err;
+ }
+ fd.Close();
+ if pd.Dev == root.Dev && pd.Ino == root.Ino {
+ break;
+ }
+ // Set up for next round.
+ dot = pd;
+ }
+ return pwd, nil
+}
diff --git a/src/lib/os/os_test.go b/src/lib/os/os_test.go
index b291fd8..e4d115d 100644
--- a/src/lib/os/os_test.go
+++ b/src/lib/os/os_test.go
@@ -316,7 +316,7 @@
if err != nil {
t.Fatalf("Pipe: %v", err);
}
- pid, err := ForkExec("/bin/pwd", []string{"pwd"}, nil, "/", []*File{nil, w, os.Stderr});
+ pid, err := ForkExec("/bin/pwd", []string{"pwd"}, nil, "/", []*File{nil, w, Stderr});
if err != nil {
t.Fatalf("ForkExec: %v", err);
}
@@ -345,12 +345,12 @@
func TestChmod(t *testing.T) {
MkdirAll("_obj", 0777);
const Path = "_obj/_TestChmod_";
- fd, err := os.Open(Path, os.O_WRONLY | os.O_CREAT, 0666);
+ fd, err := Open(Path, O_WRONLY | O_CREAT, 0666);
if err != nil {
t.Fatalf("create %s: %s", Path, err);
}
- if err = os.Chmod(Path, 0456); err != nil {
+ if err = Chmod(Path, 0456); err != nil {
t.Fatalf("chmod %s 0456: %s", Path, err);
}
checkMode(t, Path, 0456);
@@ -384,7 +384,7 @@
// basically useless.
const Path = "/tmp/_TestChown_";
- fd, err := os.Open(Path, os.O_WRONLY | os.O_CREAT, 0666);
+ fd, err := Open(Path, O_WRONLY | O_CREAT, 0666);
if err != nil {
t.Fatalf("create %s: %s", Path, err);
}
@@ -398,7 +398,7 @@
// Can't change uid unless root, but can try
// changing the group id. First try our current group.
gid := Getgid();
- if err = os.Chown(Path, -1, gid); err != nil {
+ if err = Chown(Path, -1, gid); err != nil {
t.Fatalf("chown %s -1 %d: %s", Path, gid, err);
}
checkUidGid(t, Path, int(dir.Uid), gid);
@@ -409,7 +409,7 @@
t.Fatalf("getgroups: %s", err);
}
for i, g := range groups {
- if err = os.Chown(Path, -1, g); err != nil {
+ if err = Chown(Path, -1, g); err != nil {
t.Fatalf("chown %s -1 %d: %s", Path, g, err);
}
checkUidGid(t, Path, int(dir.Uid), g);
@@ -435,7 +435,7 @@
func TestTruncate(t *testing.T) {
MkdirAll("_obj", 0777);
const Path = "_obj/_TestTruncate_";
- fd, err := os.Open(Path, os.O_WRONLY | os.O_CREAT, 0666);
+ fd, err := Open(Path, O_WRONLY | O_CREAT, 0666);
if err != nil {
t.Fatalf("create %s: %s", Path, err);
}
@@ -454,3 +454,50 @@
fd.Close();
Remove(Path);
}
+
+func TestChdirAndGetwd(t *testing.T) {
+ fd, err := Open(".", O_RDONLY, 0);
+ if err != nil {
+ t.Fatalf("Open .: %s", err);
+ }
+ // These are chosen carefully not to be symlinks on a Mac
+ // (unlike, say, /var, /etc, and /tmp).
+ dirs := []string{ "/bin", "/", "/usr/local/bin" };
+ for mode := 0; mode < 2; mode++ {
+ for i, d := range dirs {
+ if mode == 0 {
+ err = Chdir(d);
+ } else {
+ fd1, err := os.Open(d, os.O_RDONLY, 0);
+ if err != nil {
+ t.Errorf("Open %s: %s", d, err);
+ continue;
+ }
+ err = fd1.Chdir();
+ fd1.Close();
+ }
+ pwd, err1 := Getwd();
+ err2 := fd.Chdir();
+ if err2 != nil {
+ // We changed the current directory and cannot go back.
+ // Don't let the tests continue; they'll scribble
+ // all over some other directory.
+ fmt.Fprintf(Stderr, "fchdir back to dot failed: %s\n", err2);
+ Exit(1);
+ }
+ if err != nil {
+ fd.Close();
+ t.Fatalf("Chdir %s: %s", d, err);
+ }
+ if err1 != nil {
+ fd.Close();
+ t.Fatalf("Getwd in %s: %s", d, err1);
+ }
+ if pwd != d {
+ fd.Close();
+ t.Fatalf("Getwd returned %q want %q", pwd, d);
+ }
+ }
+ }
+ fd.Close();
+}
