Add "--branches", "--tags" and "--remotes" options to git-rev-parse.

"git branch" uses "rev-parse --all" and becomes much too slow when
there are many tags (it scans all refs).  Use the new "--branches"
option of rev-parse to speed things up.

Signed-off-by: Sean Estabrooks <seanlkml@sympatico.ca>
Signed-off-by: Junio C Hamano <junkio@cox.net>

Documentation/git-rev-parse.txt

@@ -67,6 +67,15 @@ OPTIONS
 --all::
 	Show all refs found in `$GIT_DIR/refs`.
 
+--branches::
+	Show branch refs found in `$GIT_DIR/refs/heads`.
+
+--tags::
+	Show tag refs found in `$GIT_DIR/refs/tags`.
+
+--remotes::
+	Show tag refs found in `$GIT_DIR/refs/remotes`.
+
 --show-prefix::
 	When the command is invoked from a subdirectory, show the
 	path of the current directory relative to the top-level

git-branch.sh

@@ -82,8 +82,7 @@ done
 
 case "$#" in
 0)
-	git-rev-parse --symbolic --all |
-	sed -ne 's|^refs/heads/||p' |
+	git-rev-parse --symbolic --branches |
 	sort |
 	while read ref
 	do

refs.c

@@ -114,7 +114,7 @@ int read_ref(const char *filename, unsigned char *sha1)
 	return -1;
 }
 
-static int do_for_each_ref(const char *base, int (*fn)(const char *path, const unsigned char *sha1))
+static int do_for_each_ref(const char *base, int (*fn)(const char *path, const unsigned char *sha1), int trim)
 {
 	int retval = 0;
 	DIR *dir = opendir(git_path("%s", base));
@@ -146,7 +146,7 @@ static int do_for_each_ref(const char *base, int (*fn)(const char *path, const u
 			if (stat(git_path("%s", path), &st) < 0)
 				continue;
 			if (S_ISDIR(st.st_mode)) {
-				retval = do_for_each_ref(path, fn);
+				retval = do_for_each_ref(path, fn, trim);
 				if (retval)
 					break;
 				continue;
@@ -160,7 +160,7 @@ static int do_for_each_ref(const char *base, int (*fn)(const char *path, const u
 				      "commit object!", path);
 				continue;
 			}
-			retval = fn(path, sha1);
+			retval = fn(path + trim, sha1);
 			if (retval)
 				break;
 		}
@@ -180,7 +180,22 @@ int head_ref(int (*fn)(const char *path, const unsigned char *sha1))
 
 int for_each_ref(int (*fn)(const char *path, const unsigned char *sha1))
 {
-	return do_for_each_ref("refs", fn);
+	return do_for_each_ref("refs", fn, 0);
+}
+
+int for_each_tag_ref(int (*fn)(const char *path, const unsigned char *sha1))
+{
+	return do_for_each_ref("refs/tags", fn, 10);
+}
+
+int for_each_branch_ref(int (*fn)(const char *path, const unsigned char *sha1))
+{
+	return do_for_each_ref("refs/heads", fn, 11);
+}
+
+int for_each_remote_ref(int (*fn)(const char *path, const unsigned char *sha1))
+{
+	return do_for_each_ref("refs/remotes", fn, 13);
 }
 
 static char *ref_file_name(const char *ref)

refs.h

@@ -7,6 +7,9 @@
  */
 extern int head_ref(int (*fn)(const char *path, const unsigned char *sha1));
 extern int for_each_ref(int (*fn)(const char *path, const unsigned char *sha1));
+extern int for_each_tag_ref(int (*fn)(const char *path, const unsigned char *sha1));
+extern int for_each_branch_ref(int (*fn)(const char *path, const unsigned char *sha1));
+extern int for_each_remote_ref(int (*fn)(const char *path, const unsigned char *sha1));
 
 /** Reads the refs file specified into sha1 **/
 extern int get_ref_sha1(const char *ref, unsigned char *sha1);

rev-parse.c

@@ -36,6 +36,7 @@ static int is_rev_argument(const char *arg)
 		"--all",
 		"--bisect",
 		"--dense",
+		"--branches",
 		"--header",
 		"--max-age=",
 		"--max-count=",
@@ -45,7 +46,9 @@ static int is_rev_argument(const char *arg)
 		"--objects-edge",
 		"--parents",
 		"--pretty",
+		"--remotes",
 		"--sparse",
+		"--tags",
 		"--topo-order",
 		"--date-order",
 		"--unpacked",
@@ -165,7 +168,7 @@ int main(int argc, char **argv)
 	int i, as_is = 0, verify = 0;
 	unsigned char sha1[20];
 	const char *prefix = setup_git_directory();
-	
+
 	git_config(git_default_config);
 
 	for (i = 1; i < argc; i++) {
@@ -255,6 +258,18 @@ int main(int argc, char **argv)
 				for_each_ref(show_reference);
 				continue;
 			}
+			if (!strcmp(arg, "--branches")) {
+				for_each_branch_ref(show_reference);
+				continue;
+			}
+			if (!strcmp(arg, "--tags")) {
+				for_each_tag_ref(show_reference);
+				continue;
+			}
+			if (!strcmp(arg, "--remotes")) {
+				for_each_remote_ref(show_reference);
+				continue;
+			}
 			if (!strcmp(arg, "--show-prefix")) {
 				if (prefix)
 					puts(prefix);