commit eb72a30f8732037596f0a1ab75c6219a40d4cf7d
author Ian Lance Taylor <iant@golang.org> Tue Jan 29 16:34:27 2019 -0800
committer Ian Lance Taylor <iant@golang.org> Wed Jan 30 01:07:50 2019 +0000
tree b2b31292eb7a406af15286d1d6017c54b65577e4
parent f1d662f34788f4a5f087581d0951cdf4e0f6e708

os: make openFdAt act like openFileNolog

- add EINTR loop on Darwin
- return PathError on error
- call newFile rather than NewFile

This tries to minimize the possibility of any future changes.
It would be nice to put openFdAt in the same file as openFileNolog,
but build tags forbid.

Updates #29983

Change-Id: I866002416d6473fbfd80ff6ef09b2bc4607f2934
Reviewed-on: https://go-review.googlesource.com/c/160181
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Damien Neil <dneil@google.com>

src/os/file_unix.go

diff --git a/src/os/file_unix.go b/src/os/file_unix.go
index 7d68a76..2615df9 100644
--- a/src/os/file_unix.go
+++ b/src/os/file_unix.go
@@ -186,6 +186,7 @@
 const DevNull = "/dev/null"
 
 // openFileNolog is the Unix implementation of OpenFile.
+// Changes here should be reflected in openFdAt, if relevant.
 func openFileNolog(name string, flag int, perm FileMode) (*File, error) {
 	setSticky := false
 	if !supportsCreateWithStickyBit && flag&O_CREATE != 0 && perm&ModeSticky != 0 {

src/os/removeall_at.go

diff --git a/src/os/removeall_at.go b/src/os/removeall_at.go
index f0fed6d..faee128 100644
--- a/src/os/removeall_at.go
+++ b/src/os/removeall_at.go
@@ -9,6 +9,7 @@
 import (
 	"internal/syscall/unix"
 	"io"
+	"runtime"
 	"syscall"
 )
 
@@ -128,11 +129,31 @@
 	return unlinkError
 }
 
-func openFdAt(fd int, path string) (*File, error) {
-	fd, err := unix.Openat(fd, path, O_RDONLY, 0)
-	if err != nil {
-		return nil, err
+// openFdAt opens path relative to the directory in fd.
+// Other than that this should act like openFileNolog.
+// This acts like openFileNolog rather than OpenFile because
+// we are going to (try to) remove the file.
+// The contents of this file are not relevant for test caching.
+func openFdAt(dirfd int, name string) (*File, error) {
+	var r int
+	for {
+		var e error
+		r, e = unix.Openat(dirfd, name, O_RDONLY, 0)
+		if e == nil {
+			break
+		}
+
+		// See comment in openFileNolog.
+		if runtime.GOOS == "darwin" && e == syscall.EINTR {
+			continue
+		}
+
+		return nil, &PathError{"openat", name, e}
 	}
 
-	return NewFile(uintptr(fd), path), nil
+	if !supportsCloseOnExec {
+		syscall.CloseOnExec(r)
+	}
+
+	return newFile(uintptr(r), name, kindOpenFile), nil
 }