Merge branch 'js/shallow'

* js/shallow:
  fetch-pack: Do not fetch tags for shallow clones.
  get_shallow_commits: Avoid memory leak if a commit has been reached already.
  git-fetch: Reset shallow_depth before auto-following tags.
  upload-pack: Check for NOT_SHALLOW flag before sending a shallow to the client.
  fetch-pack: Properly remove the shallow file when it becomes empty.
  shallow clone: unparse and reparse an unshallowed commit
  Why didn't we mark want_obj as ~UNINTERESTING in the old code?
  Why does it mean we do not have to register shallow if we have one?
  We should make sure that the protocol is still extensible.
  add tests for shallow stuff
  Shallow clone: do not ignore shallowness when following tags
  allow deepening of a shallow repository
  allow cloning a repository "shallowly"
  support fetching into a shallow repository
  upload-pack: no longer call rev-list

1 files changed, 138 insertions, 36 deletions

diff --git a/upload-pack.c b/upload-pack.c
index 32b06b2e66..c568ef066c 100644
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -6,6 +6,9 @@
 #include "object.h"
 #include "commit.h"
 #include "exec_cmd.h"
+#include "diff.h"
+#include "revision.h"
+#include "list-objects.h"
 
 static const char upload_pack_usage[] = "git-upload-pack [--strict] [--timeout=nn] <dir>";
 
@@ -16,6 +19,10 @@ static const char upload_pack_usage[] = "git-upload-pack [--strict] [--timeout=n
 #define COMMON_KNOWN	(1u << 14)
 #define REACHABLE	(1u << 15)
 
+#define SHALLOW		(1u << 16)
+#define NOT_SHALLOW	(1u << 17)
+#define CLIENT_SHALLOW	(1u << 18)
+
 static unsigned long oldest_have;
 
 static int multi_ack, nr_our_refs;
@@ -54,6 +61,40 @@ static ssize_t send_client_data(int fd, const char *data, ssize_t sz)
 	return safe_write(fd, data, sz);
 }
 
+FILE *pack_pipe = NULL;
+static void show_commit(struct commit *commit)
+{
+	if (commit->object.flags & BOUNDARY)
+		fputc('-', pack_pipe);
+	if (fputs(sha1_to_hex(commit->object.sha1), pack_pipe) < 0)
+		die("broken output pipe");
+	fputc('\n', pack_pipe);
+	fflush(pack_pipe);
+	free(commit->buffer);
+	commit->buffer = NULL;
+}
+
+static void show_object(struct object_array_entry *p)
+{
+	/* An object with name "foo\n0000000..." can be used to
+	 * confuse downstream git-pack-objects very badly.
+	 */
+	const char *ep = strchr(p->name, '\n');
+	if (ep) {
+		fprintf(pack_pipe, "%s %.*s\n", sha1_to_hex(p->item->sha1),
+		       (int) (ep - p->name),
+		       p->name);
+	}
+	else
+		fprintf(pack_pipe, "%s %s\n",
+				sha1_to_hex(p->item->sha1), p->name);
+}
+
+static void show_edge(struct commit *commit)
+{
+	fprintf(pack_pipe, "-%s\n", sha1_to_hex(commit->object.sha1));
+}
+
 static void create_pack_file(void)
 {
 	/* Pipes between rev-list to pack-objects, pack-objects to us
@@ -75,48 +116,40 @@ static void create_pack_file(void)
 
 	if (!pid_rev_list) {
 		int i;
-		int args;
-		const char **argv;
-		const char **p;
-		char *buf;
+		struct rev_info revs;
 
-		if (create_full_pack) {
-			args = 10;
-			use_thin_pack = 0; /* no point doing it */
-		}
-		else
-			args = have_obj.nr + want_obj.nr + 5;
-		p = xmalloc(args * sizeof(char *));
-		argv = (const char **) p;
-		buf = xmalloc(args * 45);
+		pack_pipe = fdopen(lp_pipe[1], "w");
 
-		dup2(lp_pipe[1], 1);
-		close(0);
-		close(lp_pipe[0]);
-		close(lp_pipe[1]);
-		*p++ = "rev-list";
-		*p++ = use_thin_pack ? "--objects-edge" : "--objects";
 		if (create_full_pack)
-			*p++ = "--all";
-		else {
+			use_thin_pack = 0; /* no point doing it */
+		init_revisions(&revs, NULL);
+		revs.tag_objects = 1;
+		revs.tree_objects = 1;
+		revs.blob_objects = 1;
+		if (use_thin_pack)
+			revs.edge_hint = 1;
+
+		if (create_full_pack) {
+			const char *args[] = {"rev-list", "--all", NULL};
+			setup_revisions(2, args, &revs, NULL);
+		} else {
 			for (i = 0; i < want_obj.nr; i++) {
 				struct object *o = want_obj.objects[i].item;
-				*p++ = buf;
-				memcpy(buf, sha1_to_hex(o->sha1), 41);
-				buf += 41;
+				/* why??? */
+				o->flags &= ~UNINTERESTING;
+				add_pending_object(&revs, o, NULL);
 			}
-		}
-		if (!create_full_pack)
 			for (i = 0; i < have_obj.nr; i++) {
 				struct object *o = have_obj.objects[i].item;
-				*p++ = buf;
-				*buf++ = '^';
-				memcpy(buf, sha1_to_hex(o->sha1), 41);
-				buf += 41;
+				o->flags |= UNINTERESTING;
+				add_pending_object(&revs, o, NULL);
 			}
-		*p++ = NULL;
-		execv_git_cmd(argv);
-		die("git-upload-pack: unable to exec git-rev-list");
+			setup_revisions(0, NULL, &revs, NULL);
+		}
+		prepare_revision_walk(&revs);
+		mark_edges_uninteresting(revs.commits, &revs, show_edge);
+		traverse_commit_list(&revs, show_commit, show_object);
+		exit(0);
 	}
 
 	if (pipe(pu_pipe) < 0)
@@ -456,8 +489,9 @@ static int get_common_commits(void)
 
 static void receive_needs(void)
 {
+	struct object_array shallows = {0, 0, NULL};
 	static char line[1000];
-	int len;
+	int len, depth = 0;
 
 	for (;;) {
 		struct object *o;
@@ -465,8 +499,29 @@ static void receive_needs(void)
 		len = packet_read_line(0, line, sizeof(line));
 		reset_timeout();
 		if (!len)
-			return;
+			break;
 
+		if (!strncmp("shallow ", line, 8)) {
+			unsigned char sha1[20];
+			struct object *object;
+			use_thin_pack = 0;
+			if (get_sha1(line + 8, sha1))
+				die("invalid shallow line: %s", line);
+			object = parse_object(sha1);
+			if (!object)
+				die("did not find object for %s", line);
+			object->flags |= CLIENT_SHALLOW;
+			add_object_array(object, NULL, &shallows);
+			continue;
+		}
+		if (!strncmp("deepen ", line, 7)) {
+			char *end;
+			use_thin_pack = 0;
+			depth = strtol(line + 7, &end, 0);
+			if (end == line + 7 || depth <= 0)
+				die("Invalid deepen: %s", line);
+			continue;
+		}
 		if (strncmp("want ", line, 5) ||
 		    get_sha1_hex(line+5, sha1_buf))
 			die("git-upload-pack: protocol error, "
@@ -498,11 +553,58 @@ static void receive_needs(void)
 			add_object_array(o, NULL, &want_obj);
 		}
 	}
+	if (depth == 0 && shallows.nr == 0)
+		return;
+	if (depth > 0) {
+		struct commit_list *result, *backup;
+		int i;
+		backup = result = get_shallow_commits(&want_obj, depth,
+			SHALLOW, NOT_SHALLOW);
+		while (result) {
+			struct object *object = &result->item->object;
+			if (!(object->flags & (CLIENT_SHALLOW|NOT_SHALLOW))) {
+				packet_write(1, "shallow %s",
+						sha1_to_hex(object->sha1));
+				register_shallow(object->sha1);
+			}
+			result = result->next;
+		}
+		free_commit_list(backup);
+		for (i = 0; i < shallows.nr; i++) {
+			struct object *object = shallows.objects[i].item;
+			if (object->flags & NOT_SHALLOW) {
+				struct commit_list *parents;
+				packet_write(1, "unshallow %s",
+					sha1_to_hex(object->sha1));
+				object->flags &= ~CLIENT_SHALLOW;
+				/* make sure the real parents are parsed */
+				unregister_shallow(object->sha1);
+				object->parsed = 0;
+				parse_commit((struct commit *)object);
+				parents = ((struct commit *)object)->parents;
+				while (parents) {
+					add_object_array(&parents->item->object,
+							NULL, &want_obj);
+					parents = parents->next;
+				}
+			}
+			/* make sure commit traversal conforms to client */
+			register_shallow(object->sha1);
+		}
+		packet_flush(1);
+	} else
+		if (shallows.nr > 0) {
+			int i;
+			for (i = 0; i < shallows.nr; i++)
+				register_shallow(shallows.objects[i].item->sha1);
+		}
+	free(shallows.objects);
 }
 
 static int send_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 {
-	static const char *capabilities = "multi_ack thin-pack side-band side-band-64k ofs-delta";
+	static const char *capabilities = "multi_ack thin-pack side-band"
+		" side-band-64k ofs-delta shallow";
 	struct object *o = parse_object(sha1);
 
 	if (!o)