> On 17 Aug 2016, at 14:41, Johannes Schindelin <johannes.schinde...@gmx.de> > wrote: > > From: Ben Wijen <b...@wijen.net> > > When the index is locked and child processes inherit the handle to > said lock and the parent process wants to remove the lock before the > child process exits, on Windows there is a problem: it won't work > because files cannot be deleted if a process holds a handle on them. > The symptom: > > Rename from 'xxx/.git/index.lock' to 'xxx/.git/index' failed. > Should I try again? (y/n) > > Spawning child processes with bInheritHandles==FALSE would not work > because no file handles would be inherited, not even the hStdXxx > handles in STARTUPINFO (stdin/stdout/stderr). > > Opening every file with O_NOINHERIT does not work, either, as e.g. > git-upload-pack expects inherited file handles. > > This leaves us with the only way out: creating temp files with the > O_NOINHERIT flag. This flag is Windows-specific, however. For our > purposes, it is equivalent our purposes) to O_CLOEXEC (which does not > exist on Windows), so let's just open temporary files with the > O_CLOEXEC flag and map that flag to O_NOINHERIT on Windows. > > This fixes the test that we just introduced to demonstrate the problem. > > Signed-off-by: Ben Wijen <b...@wijen.net> > Signed-off-by: Johannes Schindelin <johannes.schinde...@gmx.de> > --- > compat/mingw.h | 4 ++++ > t/t6026-merge-attr.sh | 2 +- > tempfile.c | 2 +- > 3 files changed, 6 insertions(+), 2 deletions(-) > > diff --git a/compat/mingw.h b/compat/mingw.h > index 95e128f..753e641 100644 > --- a/compat/mingw.h > +++ b/compat/mingw.h > @@ -67,6 +67,10 @@ typedef int pid_t; > #define F_SETFD 2 > #define FD_CLOEXEC 0x1 > > +#if !defined O_CLOEXEC && defined O_NOINHERIT > +#define O_CLOEXEC O_NOINHERIT > +#endif > + > #ifndef EAFNOSUPPORT > #define EAFNOSUPPORT WSAEAFNOSUPPORT > #endif > diff --git a/t/t6026-merge-attr.sh b/t/t6026-merge-attr.sh > index 3d28c78..dd8f88d 100755 > --- a/t/t6026-merge-attr.sh > +++ b/t/t6026-merge-attr.sh > @@ -181,7 +181,7 @@ test_expect_success 'up-to-date merge without common > ancestor' ' > ) > ' > > -test_expect_success !MINGW 'custom merge does not lock index' ' > +test_expect_success 'custom merge does not lock index' ' > git reset --hard anchor && > write_script sleep-one-second.sh <<-\EOF && > sleep 1 & > diff --git a/tempfile.c b/tempfile.c > index 0af7ebf..db3981d 100644 > --- a/tempfile.c > +++ b/tempfile.c > @@ -120,7 +120,7 @@ int create_tempfile(struct tempfile *tempfile, const char > *path) > prepare_tempfile_object(tempfile); > > strbuf_add_absolute_path(&tempfile->filename, path); > - tempfile->fd = open(tempfile->filename.buf, O_RDWR | O_CREAT | O_EXCL, > 0666); > + tempfile->fd = open(tempfile->filename.buf, O_RDWR | O_CREAT | O_EXCL | > O_CLOEXEC, 0666);
This solution works great for me. I struggled with a similar problem in my Git filter protocol series: http://public-inbox.org/git/20160810130411.12419-16-larsxschnei...@gmail.com/ I also tried selectively disabling inheritance for file handles but it looks like as this is not easily possible right now: https://github.com/git-for-windows/git/issues/770#issuecomment-238816331 - Lars-- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
