Add support to git-branch to show local and remote branches

Instead of storing a list of refnames in append_ref, a list of
structures is created.  Each of these stores the refname and a
symbolic constant representing its type.

The creation of the list is filtered based on a command line
switch; no switch means "local branches only", "-r" means "remote
branches only" (as they always did); but now "-a" means "local
branches or remote branches".

As a side effect, the list is now not global, but allocated in
print_ref_list() where it used.

Also a memory leak is plugged, the memory allocated during the
list creation was never freed.

It lays a groundwork to also display tags, but the command being
'git branch' it is not currently used.

Signed-off-by: Andy Parkins <andyparkins@gmail.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>

Documentation/git-branch.txt

@@ -8,14 +8,16 @@ git-branch - List, create, or delete branches.
 SYNOPSIS
 --------
 [verse]
-'git-branch' [-r]
+'git-branch' [-r] [-a]
 'git-branch' [-l] [-f] <branchname> [<start-point>]
 'git-branch' (-d | -D) <branchname>...
 
 DESCRIPTION
 -----------
-With no arguments given (or just `-r`) a list of available branches
+With no arguments given a list of existing branches
 will be shown, the current branch will be highlighted with an asterisk.
+Option `-r` causes the remote-tracking branches to be listed,
+and option `-a` shows both.
 
 In its second form, a new branch named <branchname> will be created.
 It will start out with a head equal to the one given as <start-point>.
@@ -45,7 +47,10 @@ OPTIONS
 	a branch that already exists with the same name.
 
 -r::
-	List only the "remote" branches.
+	List the remote-tracking branches.
+
+-a::
+	List both remote-tracking branches and local branches.
 
 <branchname>::
 	The name of the branch to create or delete.

builtin-branch.c

@@ -11,7 +11,7 @@
 #include "builtin.h"
 
 static const char builtin_branch_usage[] =
-"git-branch (-d | -D) <branchname> | [-l] [-f] <branchname> [<start-point>] | [-r]";
+"git-branch (-d | -D) <branchname> | [-l] [-f] <branchname> [<start-point>] | [-r] | [-a]";
 
 
 static const char *head;
@@ -79,46 +79,100 @@ static void delete_branches(int argc, const char **argv, int force)
 	}
 }
 
-static int ref_index, ref_alloc;
-static char **ref_list;
+#define REF_UNKNOWN_TYPE    0x00
+#define REF_LOCAL_BRANCH    0x01
+#define REF_REMOTE_BRANCH   0x02
+#define REF_TAG             0x04
 
-static int append_ref(const char *refname, const unsigned char *sha1, int flags,
-		void *cb_data)
+struct ref_item {
+	char *name;
+	unsigned int kind;
+};
+
+struct ref_list {
+	int index, alloc;
+	struct ref_item *list;
+	int kinds;
+};
+
+static int append_ref(const char *refname, const unsigned char *sha1, int flags, void *cb_data)
 {
-	if (ref_index >= ref_alloc) {
-		ref_alloc = alloc_nr(ref_alloc);
-		ref_list = xrealloc(ref_list, ref_alloc * sizeof(char *));
+	struct ref_list *ref_list = (struct ref_list*)(cb_data);
+	struct ref_item *newitem;
+	int kind = REF_UNKNOWN_TYPE;
+
+	/* Detect kind */
+	if (!strncmp(refname, "refs/heads/", 11)) {
+		kind = REF_LOCAL_BRANCH;
+		refname += 11;
+	} else if (!strncmp(refname, "refs/remotes/", 13)) {
+		kind = REF_REMOTE_BRANCH;
+		refname += 13;
+	} else if (!strncmp(refname, "refs/tags/", 10)) {
+		kind = REF_TAG;
+		refname += 10;
+	}
+
+	/* Don't add types the caller doesn't want */
+	if ((kind & ref_list->kinds) == 0)
+		return 0;
+
+	/* Resize buffer */
+	if (ref_list->index >= ref_list->alloc) {
+		ref_list->alloc = alloc_nr(ref_list->alloc);
+		ref_list->list = xrealloc(ref_list->list,
+				ref_list->alloc * sizeof(struct ref_item));
 	}
 
-	ref_list[ref_index++] = xstrdup(refname);
+	/* Record the new item */
+	newitem = &(ref_list->list[ref_list->index++]);
+	newitem->name = xstrdup(refname);
+	newitem->kind = kind;
 
 	return 0;
 }
 
+static void free_ref_list(struct ref_list *ref_list)
+{
+	int i;
+
+	for (i = 0; i < ref_list->index; i++)
+		free(ref_list->list[i].name);
+	free(ref_list->list);
+}
+
 static int ref_cmp(const void *r1, const void *r2)
 {
-	return strcmp(*(char **)r1, *(char **)r2);
+	struct ref_item *c1 = (struct ref_item *)(r1);
+	struct ref_item *c2 = (struct ref_item *)(r2);
+
+	if (c1->kind != c2->kind)
+		return c1->kind - c2->kind;
+	return strcmp(c1->name, c2->name);
 }
 
-static void print_ref_list(int remote_only)
+static void print_ref_list(int kinds)
 {
 	int i;
 	char c;
+	struct ref_list ref_list;
 
-	if (remote_only)
-		for_each_remote_ref(append_ref, NULL);
-	else
-		for_each_branch_ref(append_ref, NULL);
+	memset(&ref_list, 0, sizeof(ref_list));
+	ref_list.kinds = kinds;
+	for_each_ref(append_ref, &ref_list);
 
-	qsort(ref_list, ref_index, sizeof(char *), ref_cmp);
+	qsort(ref_list.list, ref_list.index, sizeof(struct ref_item), ref_cmp);
 
-	for (i = 0; i < ref_index; i++) {
+	for (i = 0; i < ref_list.index; i++) {
 		c = ' ';
-		if (!strcmp(ref_list[i], head))
+		if (ref_list.list[i].kind == REF_LOCAL_BRANCH &&
+				!strcmp(ref_list.list[i].name, head))
 			c = '*';
 
-		printf("%c %s\n", c, ref_list[i]);
+		printf("%c %s\n", c, ref_list.list[i].name);
 	}
+
+	free_ref_list(&ref_list);
 }
 
 static void create_branch(const char *name, const char *start,
@@ -160,8 +214,9 @@ static void create_branch(const char *name, const char *start,
 
 int cmd_branch(int argc, const char **argv, const char *prefix)
 {
-	int delete = 0, force_delete = 0, force_create = 0, remote_only = 0;
+	int delete = 0, force_delete = 0, force_create = 0;
 	int reflog = 0;
+	int kinds = REF_LOCAL_BRANCH;
 	int i;
 
 	git_config(git_default_config);
@@ -189,7 +244,11 @@ int cmd_branch(int argc, const char **argv, const char *prefix)
 			continue;
 		}
 		if (!strcmp(arg, "-r")) {
-			remote_only = 1;
+			kinds = REF_REMOTE_BRANCH;
+			continue;
+		}
+		if (!strcmp(arg, "-a")) {
+			kinds = REF_REMOTE_BRANCH | REF_LOCAL_BRANCH;
 			continue;
 		}
 		if (!strcmp(arg, "-l")) {
@@ -209,7 +268,7 @@ int cmd_branch(int argc, const char **argv, const char *prefix)
 	if (delete)
 		delete_branches(argc - i, argv + i, force_delete);
 	else if (i == argc)
-		print_ref_list(remote_only);
+		print_ref_list(kinds);
 	else if (i == argc - 1)
 		create_branch(argv[i], head, force_create, reflog);
 	else if (i == argc - 2)