[PATCH v6 0/6] recursively grep across submodules

[Brandon Williams <bmwill@google.com>]

v6 fixes a race condition which existed in the 'is_submodule_populated'
function.  Instead of calling 'resolve_gitdir' to check for the existance of a
.git file/directory, use 'stat'.  'resolve_gitdir' calls 'chdir' which can
affect other running threads trying to load thier files into a buffer in
memory.

Thanks to Stefan and Jeff for help debugging this problem.

Brandon Williams (6):
  submodules: add helper functions to determine presence of submodules
  submodules: load gitmodules file from commit sha1
  grep: add submodules as a grep source type
  grep: optionally recurse into submodules
  grep: enable recurse-submodules to work on <tree> objects
  grep: search history of moved submodules

 Documentation/git-grep.txt         |  14 ++
 builtin/grep.c                     | 386 ++++++++++++++++++++++++++++++++++---
 cache.h                            |   2 +
 config.c                           |   8 +-
 git.c                              |   2 +-
 grep.c                             |  16 +-
 grep.h                             |   1 +
 submodule-config.c                 |   6 +-
 submodule-config.h                 |   3 +
 submodule.c                        |  51 +++++
 submodule.h                        |   3 +
 t/t7814-grep-recurse-submodules.sh | 241 +++++++++++++++++++++++
 tree-walk.c                        |  28 +++
 13 files changed, 730 insertions(+), 31 deletions(-)
 create mode 100755 t/t7814-grep-recurse-submodules.sh

--- interdiff based on 'bw/grep-recurse-submodules'

diff --git a/submodule.c b/submodule.c
index 062e58b..8516ab0 100644
--- a/submodule.c
+++ b/submodule.c
@@ -239,9 +239,10 @@ int is_submodule_initialized(const char *path)
 int is_submodule_populated(const char *path)
 {
 	int ret = 0;
+	struct stat st;
 	char *gitdir = xstrfmt("%s/.git", path);
 
-	if (resolve_gitdir(gitdir))
+	if (!stat(gitdir, &st))
 		ret = 1;
 
 	free(gitdir);

-- 
2.8.0.rc3.226.g39d4020