syscallcompat: OSX: add Unlinkat wrapper

Also, replace remaining naked syscall.Openat calls.

2 files changed, 22 insertions, 0 deletions

diff --git a/internal/syscallcompat/sys_darwin.go b/internal/syscallcompat/sys_darwin.go
index 7d39484..6300317 100644
--- a/internal/syscallcompat/sys_darwin.go
+++ b/internal/syscallcompat/sys_darwin.go
@@ -69,6 +69,24 @@ func Renameat(olddirfd int, oldpath string, newdirfd int, newpath string) (err e
 	return syscall.Rename(oldpath, newpath)
 }
 
+// Poor man's Unlinkat
+func Unlinkat(dirfd int, path string) (err error) {
+	chdirMutex.Lock()
+	defer chdirMutex.Unlock()
+	if !filepath.IsAbs(path) {
+		oldWd, err := os.Getwd()
+		if err != nil {
+			return err
+		}
+		defer os.Chdir(oldWd)
+	}
+	path, err = dirfdAbs(dirfd, path)
+	if err != nil {
+		return err
+	}
+	return syscall.Unlink(path)
+}
+
 // dirfdAbs transforms the dirfd-relative "path" to an absolute one. If the
 // path is not already absolute, this function will change the working
 // directory. The caller has to chdir back.
diff --git a/internal/syscallcompat/sys_linux.go b/internal/syscallcompat/sys_linux.go
index e12d100..ded5d17 100644
--- a/internal/syscallcompat/sys_linux.go
+++ b/internal/syscallcompat/sys_linux.go
@@ -48,3 +48,7 @@ func Openat(dirfd int, path string, flags int, mode uint32) (fd int, err error)
 func Renameat(olddirfd int, oldpath string, newdirfd int, newpath string) (err error) {
 	return syscall.Renameat(olddirfd, oldpath, newdirfd, newpath)
 }
+
+func Unlinkat(dirfd int, path string) error {
+	return syscall.Unlinkat(dirfd, path)
+}