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|
package syscallcompat
import (
"bytes"
"os"
"runtime"
"syscall"
"testing"
"golang.org/x/sys/unix"
)
func TestReadlinkat(t *testing.T) {
for _, targetLen := range []int{100, 500, 4000} {
target := string(bytes.Repeat([]byte("x"), targetLen))
err := syscall.Symlink(target, tmpDir+"/readlinkat")
if err != nil {
if targetLen > 1000 {
// Symlinks longer than 1024 (?) bytes are not supported on
// MacOS and XFS
t.Logf("skipping targetLen=%d: %v", targetLen, err)
continue
}
t.Fatalf("targetLen=%d: %v", targetLen, err)
}
target2, err := Readlinkat(tmpDirFd, "readlinkat")
if err != nil {
t.Fatal(err)
}
if target != target2 {
t.Errorf("target=%q != target2=%q", target, target2)
}
err = syscall.Unlink(tmpDir + "/readlinkat")
if err != nil {
t.Fatal(err)
}
}
}
func TestOpenat(t *testing.T) {
_, err := Openat(tmpDirFd, "testOpenAt", 0, 0)
if err == nil {
t.Errorf("should have failed")
}
fd, err := os.Create(tmpDir + "/testOpenAt")
if err != nil {
t.Fatal(err)
}
fd.Close()
rawFd, err := Openat(tmpDirFd, "testOpenAt", 0, 0)
if err != nil {
t.Fatal(err)
}
defer syscall.Close(rawFd)
if rawFd < 0 {
t.Fatalf("rawFd=%d", rawFd)
}
// Test with absolute path
rawFd, err = Openat(-1, tmpDir+"/testOpenAt", 0, 0)
if err != nil {
t.Fatal(err)
}
defer syscall.Close(rawFd)
if rawFd < 0 {
t.Fatalf("rawFd=%d", rawFd)
}
}
func TestRenameat(t *testing.T) {
os.Mkdir(tmpDir+"/dir1", 0700)
dir1, err := os.Open(tmpDir + "/dir1")
if err != nil {
t.Fatal(err)
}
defer dir1.Close()
os.Mkdir(tmpDir+"/dir2", 0700)
dir2, err := os.Open(tmpDir + "/dir2")
if err != nil {
t.Fatal(err)
}
defer dir2.Close()
fd, err := os.Create(tmpDir + "/dir1/f1")
if err != nil {
t.Fatal(err)
}
fd.Close()
err = Renameat(int(dir1.Fd()), "f1", int(dir2.Fd()), "f2")
if err != nil {
t.Fatal(err)
}
_, err = os.Stat(tmpDir + "/dir2/f2")
if err != nil {
t.Fatal(err)
}
// Test with absolute path
err = Renameat(-1, tmpDir+"/dir2/f2", -1, tmpDir+"/dir2/f1")
if err != nil {
t.Fatal(err)
}
_, err = os.Stat(tmpDir + "/dir2/f1")
if err != nil {
t.Fatal(err)
}
}
func TestUnlinkat(t *testing.T) {
os.Mkdir(tmpDir+"/unlink1", 0700)
dirfd, err := os.Open(tmpDir + "/unlink1")
if err != nil {
t.Fatal(err)
}
defer dirfd.Close()
// Try to delete file
fd, err := os.Create(tmpDir + "/unlink1/f1")
if err != nil {
t.Fatal(err)
}
fd.Close()
err = Unlinkat(int(dirfd.Fd()), "f1", 0)
if err != nil {
t.Fatal(err)
}
_, err = os.Stat(tmpDir + "/unlink1/f1")
if err == nil {
t.Fatalf("file not deleted!")
}
// Try to delete dir
err = os.Mkdir(tmpDir+"/unlink1/d1", 0700)
if err != nil {
t.Fatal(err)
}
err = Unlinkat(int(dirfd.Fd()), "d1", 0)
if err == nil {
t.Fatalf("this should fail due to missing AT_REMOVEDIR flag")
}
err = Unlinkat(int(dirfd.Fd()), "d1", unix.AT_REMOVEDIR)
if err != nil {
t.Fatal(err)
}
_, err = os.Stat(tmpDir + "/unlink1/d1")
if err == nil {
t.Fatalf("dir not deleted!")
}
// Test with absolute path
err = os.Mkdir(tmpDir+"/unlink1/d1", 0700)
if err != nil {
t.Fatal(err)
}
err = Unlinkat(-1, tmpDir+"/unlink1/d1", unix.AT_REMOVEDIR)
if err != nil {
t.Fatal(err)
}
_, err = os.Stat(tmpDir + "/unlink1/d1")
if err == nil {
t.Fatalf("dir not deleted!")
}
}
func TestFchmodat(t *testing.T) {
regular := "TestFchmodat_Regular"
f, err := os.OpenFile(tmpDir+"/"+regular, os.O_CREATE|os.O_WRONLY, 0000)
if err != nil {
t.Fatal(err)
}
f.Close()
symlink := "TestFchmodat_Symlink"
err = syscall.Symlink(regular, tmpDir+"/"+symlink)
if err != nil {
t.Fatal(err)
}
dirfd, err := syscall.Open(tmpDir, syscall.O_RDONLY, 0)
if err != nil {
t.Fatal(err)
}
defer syscall.Close(dirfd)
// Check that chmod on a regular file works ok
err = Fchmodat(dirfd, regular, 0111, 0)
if err != nil {
t.Fatal(err)
}
var st syscall.Stat_t
syscall.Lstat(tmpDir+"/"+regular, &st)
st.Mode &= 0777
if st.Mode != 0111 {
t.Errorf("wrong mode: %#0o", st.Mode)
}
err = Fchmodat(dirfd, regular, 0000, 0)
if err != nil {
t.Error(err)
}
syscall.Lstat(tmpDir+"/"+regular, &st)
st.Mode &= 0777
if st.Mode != 0000 {
t.Errorf("wrong mode: %#0o", st.Mode)
}
// Check what happens on a symlink
err = Fchmodat(dirfd, symlink, 0333, 0)
if err == nil {
syscall.Lstat(tmpDir+"/"+symlink, &st)
st.Mode &= 0777
t.Errorf("chmod on symlink should have failed, but did not. New mode=%#0o", st.Mode)
}
syscall.Lstat(tmpDir+"/"+regular, &st)
st.Mode &= 0777
if st.Mode != 0000 {
t.Errorf("chmod on symlink affected symlink target: New mode=%#0o", st.Mode)
}
}
// symlinkCheckMode looks if the mode bits in "st" say that this is a symlink.
// Calls t.Fatal() if not.
func symlinkCheckMode(t *testing.T, st syscall.Stat_t) {
if runtime.GOOS == "darwin" {
// On MacOS, symlinks don't carry their own permissions, so
// only check the file type.
if st.Mode&syscall.S_IFMT != syscall.S_IFLNK {
t.Fatalf("This is not a symlink: mode = 0%o", st.Mode)
}
return
}
if st.Mode != 0120777 {
t.Fatalf("Wrong mode, have 0%o, want 0120777", st.Mode)
}
}
func TestSymlinkat(t *testing.T) {
err := Symlinkat("/foo/bar/baz", tmpDirFd, "symlink1")
if err != nil {
t.Fatal(err)
}
var st syscall.Stat_t
err = syscall.Lstat(tmpDir+"/symlink1", &st)
if err != nil {
t.Fatal(err)
}
symlinkCheckMode(t, st)
// Test with absolute path
err = Symlinkat("/foo/bar/baz", -1, tmpDir+"/symlink2")
if err != nil {
t.Fatal(err)
}
err = syscall.Lstat(tmpDir+"/symlink2", &st)
if err != nil {
t.Fatal(err)
}
symlinkCheckMode(t, st)
}
func TestMkdirat(t *testing.T) {
err := Mkdirat(tmpDirFd, "mkdirat", 0700)
if err != nil {
t.Fatal(err)
}
fi, err := os.Stat(tmpDir + "/mkdirat")
if err != nil {
t.Fatal(err)
}
if !fi.IsDir() {
t.Fatalf("mkdirat did not create a directory")
}
// Test with absolute path
err = Mkdirat(-1, tmpDir+"/mkdirat2", 0700)
if err != nil {
t.Fatal(err)
}
fi, err = os.Stat(tmpDir + "/mkdirat2")
if err != nil {
t.Fatal(err)
}
if !fi.IsDir() {
t.Fatalf("mkdirat did not create a directory")
}
}
func TestFstatat(t *testing.T) {
var st unix.Stat_t
// stat a normal file (size 3)
f, err := os.Create(tmpDir + "/fstatat")
if err != nil {
t.Fatal(err)
}
_, err = f.Write([]byte("foo"))
if err != nil {
t.Fatal(err)
}
f.Close()
err = Fstatat(tmpDirFd, "fstatat", &st, unix.AT_SYMLINK_NOFOLLOW)
if err != nil {
t.Fatal(err)
}
if st.Size != 3 {
t.Errorf("wrong file size: %d", st.Size)
}
// stat a symlink and check that the size matches the length of the
// symlink target. This proves that we have stat'ed the symlink itself.
err = os.Symlink(tmpDir+"/fstatat", tmpDir+"/fstatatSymlink")
if err != nil {
t.Fatal(err)
}
err = Fstatat(tmpDirFd, "fstatatSymlink", &st, unix.AT_SYMLINK_NOFOLLOW)
if err != nil {
t.Fatal(err)
}
expectedSize := int64(len(tmpDir + "/fstatat"))
if st.Size != expectedSize {
t.Errorf("symlink size: expected=%d, got=%d", expectedSize, st.Size)
}
}
|
