Re: Passing tar(1) options via git-archive(1)

From

Jeff King <peff@peff.net>

Date

Sep 24, 2014, 05:46 UTC

Message-ID

<20140924054624.GB24141@peff.net>

In-Reply-To

<87k34tizb5.fsf@brockman.se>

On Wed, Sep 24, 2014 at 03:26:22AM +0200, Daniel Brockman wrote:

> "brian m. carlson" <sandals@crustytoothpaste.net> writes:
> 
> > Git does not invoke tar(1).  It has its own tar (actually, pax)
> > implementation, so any options would have to be implemented in Git.
> > We'd probably want to make such a change effective in the zip format
> > as well.
> 
> Ah, I see...
> 
> Well, I guess in the meantime I'll just do this:
> 
>    git commit -m dummy --allow-empty --date=1970-01-01T00:00:00Z
>    git archive HEAD | docker build -
>    git reset HEAD~

  commit=$(
    GIT_COMMITTER_DATE=1970-01-01T00:00:00Z \
    git commit-tree HEAD^{tree} </dev/null
  )
  git archive $commit | ...

However, the --mtime patch you are asking for is really not that big:

diff --git a/archive.c b/archive.c
index 952a659..9396fca 100644
--- a/archive.c
+++ b/archive.c
@@ -299,7 +299,8 @@ static void parse_treeish_arg(const char **argv,
 	ar_args->tree = tree;
 	ar_args->commit_sha1 = commit_sha1;
 	ar_args->commit = commit;
-	ar_args->time = archive_time;
+	if (!ar_args->time)
+		ar_args->time = archive_time;
 }
 
 #define OPT__COMPR(s, v, h, p) \
@@ -323,6 +324,7 @@ static int parse_archive_args(int argc, const char **argv,
 	int i;
 	int list = 0;
 	int worktree_attributes = 0;
+	unsigned long mtime = 0;
 	struct option opts[] = {
 		OPT_GROUP(""),
 		OPT_STRING(0, "format", &format, N_("fmt"), N_("archive format")),
@@ -332,6 +334,7 @@ static int parse_archive_args(int argc, const char **argv,
 			N_("write the archive to this file")),
 		OPT_BOOL(0, "worktree-attributes", &worktree_attributes,
 			N_("read .gitattributes in working directory")),
+		OPT_DATE(0, "mtime", &mtime, N_("mtime of files in archive")),
 		OPT__VERBOSE(&verbose, N_("report archived files on stderr")),
 		OPT__COMPR('0', &compression_level, N_("store only"), 0),
 		OPT__COMPR('1', &compression_level, N_("compress faster"), 1),
@@ -398,6 +401,7 @@ static int parse_archive_args(int argc, const char **argv,
 	args->base = base;
 	args->baselen = strlen(base);
 	args->worktree_attributes = worktree_attributes;
+	args->time = mtime;
 
 	return argc;
 }

which allows:

  git archive --mtime='yesterday at 3pm' HEAD

For inclusion in git, it would need someone to wrap it up with a commit
message, and add a basic test (see the existing mtime test in
t/t5000-tar-tree) and documentation in Documentation/git-archive.txt.
That someone could be you. :)

-Peff