[PATCH/RFC 1/7] list-objects: add sparse-prefix option to rev_info

[Robin Ruede <r.ruede@gmail.com>]

this skips all blob objects who's path does not begin with the specified
prefix

Signed-off-by: Robin Ruede <r.ruede@gmail.com>
---
 list-objects.c | 4 +++-
 revision.c     | 4 ++++
 revision.h     | 1 +
 3 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/list-objects.c b/list-objects.c
index f3ca6aa..91a6091 100644
--- a/list-objects.c
+++ b/list-objects.c
@@ -28,7 +28,9 @@ static void process_blob(struct rev_info *revs,
 
 	pathlen = path->len;
 	strbuf_addstr(path, name);
-	show(obj, path->buf, cb_data);
+	if (!revs->sparse_prefix || starts_with(path->buf, revs->sparse_prefix + 1)) {
+		show(obj, path->buf, cb_data);
+	}
 	strbuf_setlen(path, pathlen);
 }
 
diff --git a/revision.c b/revision.c
index edba5b7..a36a796 100644
--- a/revision.c
+++ b/revision.c
@@ -1664,6 +1664,10 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg
 	} else if ((argcount = parse_long_opt("skip", argv, &optarg))) {
 		revs->skip_count = atoi(optarg);
 		return argcount;
+	} else if ((argcount = parse_long_opt("sparse-prefix", argv, &optarg))) {
+		if(optarg[0] != '/') return error(N_("sparse prefix must start with /"));
+		revs->sparse_prefix = optarg;
+		return argcount;
 	} else if ((*arg == '-') && isdigit(arg[1])) {
 		/* accept -<digit>, like traditional "head" */
 		if (strtol_i(arg + 1, 10, &revs->max_count) < 0 ||
diff --git a/revision.h b/revision.h
index 9fac1a6..2c7c5f2 100644
--- a/revision.h
+++ b/revision.h
@@ -113,6 +113,7 @@ struct rev_info {
 			ancestry_path:1,
 			first_parent_only:1,
 			line_level_traverse:1;
+	const char *sparse_prefix;
 
 	/* Diff flags */
 	unsigned int	diff:1,
-- 
2.9.1.283.g3ca5b4c.dirty