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[RFC PATCH v2 03/16] fetch-pack: Use a strbuf to compose the want list

From
Shawn O. Pearce <spearce@spearce.org>
Date
Oct 13, 2009, 02:25 UTC
Message-ID
<1255400715-10508-4-git-send-email-spearce@spearce.org>
In-Reply-To
<1255400715-10508-1-git-send-email-spearce@spearce.org>

This change is being offered as a refactoring to make later commits in the smart HTTP series easier.

By changing the enabled capabilities to be formatted in a strbuf it is easier to add a new capability to the set of supported capabilities.

By formatting the want portion of the request into a strbuf and writing it as a whole block we can later decide to hold onto the req_buf (instead of releasing it) to recycle in stateless communications.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
---
 builtin-fetch-pack.c |   52 ++++++++++++++++++++++++++++++++-----------------
 commit.c             |   10 +++-----
 commit.h             |    2 +-
 3 files changed, 39 insertions(+), 25 deletions(-)
diff --git a/builtin-fetch-pack.c b/builtin-fetch-pack.c
index 629735f..783c2b0 100644
--- a/builtin-fetch-pack.c
+++ b/builtin-fetch-pack.c
@@ -165,6 +165,7 @@ static int find_common(int fd[2], unsigned char *result_sha1,
 	const unsigned char *sha1;
 	unsigned in_vain = 0;
 	int got_continue = 0;
+	struct strbuf req_buf = STRBUF_INIT;
 
 	if (marked)
 		for_each_ref(clear_marks, NULL);
@@ -175,6 +176,7 @@ static int find_common(int fd[2], unsigned char *result_sha1,
 	fetching = 0;
 	for ( ; refs ; refs = refs->next) {
 		unsigned char *remote = refs->old_sha1;
+		const char *remote_hex;
 		struct object *o;
 
 		/*
@@ -192,27 +194,36 @@ static int find_common(int fd[2], unsigned char *result_sha1,
 			continue;
 		}
 
-		if (!fetching)
-			packet_write(fd[1], "want %s%s%s%s%s%s%s%s\n",
-				     sha1_to_hex(remote),
-				     (multi_ack ? " multi_ack" : ""),
-				     (use_sideband == 2 ? " side-band-64k" : ""),
-				     (use_sideband == 1 ? " side-band" : ""),
-				     (args.use_thin_pack ? " thin-pack" : ""),
-				     (args.no_progress ? " no-progress" : ""),
-				     (args.include_tag ? " include-tag" : ""),
-				     (prefer_ofs_delta ? " ofs-delta" : ""));
-		else
-			packet_write(fd[1], "want %s\n", sha1_to_hex(remote));
+		remote_hex = sha1_to_hex(remote);
+		if (!fetching) {
+			struct strbuf c = STRBUF_INIT;
+			if (multi_ack)          strbuf_addstr(&c, " multi_ack");
+			if (use_sideband == 2)  strbuf_addstr(&c, " side-band-64k");
+			if (use_sideband == 1)  strbuf_addstr(&c, " side-band");
+			if (args.use_thin_pack) strbuf_addstr(&c, " thin-pack");
+			if (args.no_progress)   strbuf_addstr(&c, " no-progress");
+			if (args.include_tag)   strbuf_addstr(&c, " include-tag");
+			if (prefer_ofs_delta)   strbuf_addstr(&c, " ofs-delta");
+			packet_buf_write(&req_buf, "want %s%s\n", remote_hex, c.buf);
+			strbuf_release(&c);
+		} else
+			packet_buf_write(&req_buf, "want %s\n", remote_hex);
 		fetching++;
 	}
+
+	if (!fetching) {
+		strbuf_release(&req_buf);
+		packet_flush(fd[1]);
+		return 1;
+	}
+
 	if (is_repository_shallow())
-		write_shallow_commits(fd[1], 1);
+		write_shallow_commits(&req_buf, 1);
 	if (args.depth > 0)
-		packet_write(fd[1], "deepen %d", args.depth);
-	packet_flush(fd[1]);
-	if (!fetching)
-		return 1;
+		packet_buf_write(&req_buf, "deepen %d", args.depth);
+	packet_buf_flush(&req_buf);
+
+	safe_write(fd[1], req_buf.buf, req_buf.len);
 
 	if (args.depth > 0) {
 		char line[1024];
@@ -296,6 +307,8 @@ done:
 		multi_ack = 0;
 		flushes++;
 	}
+	strbuf_release(&req_buf);
+
 	while (flushes || multi_ack) {
 		int ack = get_ack(fd[0], result_sha1);
 		if (ack) {
@@ -809,6 +822,7 @@ struct ref *fetch_pack(struct fetch_pack_args *my_args,
 
 	if (args.depth > 0) {
 		struct cache_time mtime;
+		struct strbuf sb = STRBUF_INIT;
 		char *shallow = git_path("shallow");
 		int fd;
 
@@ -826,12 +840,14 @@ struct ref *fetch_pack(struct fetch_pack_args *my_args,
 
 		fd = hold_lock_file_for_update(&lock, shallow,
 					       LOCK_DIE_ON_ERROR);
-		if (!write_shallow_commits(fd, 0)) {
+		if (!write_shallow_commits(&sb, 0)
+		 || write_in_full(fd, sb.buf, sb.len) != sb.len) {
 			unlink_or_warn(shallow);
 			rollback_lock_file(&lock);
 		} else {
 			commit_lock_file(&lock);
 		}
+		strbuf_release(&sb);
 	}
 
 	reprepare_packed_git();
diff --git a/commit.c b/commit.c
index fedbd5e..471efb0 100644
--- a/commit.c
+++ b/commit.c
@@ -199,7 +199,7 @@ struct commit_graft *lookup_commit_graft(const unsigned char *sha1)
 	return commit_graft[pos];
 }
 
-int write_shallow_commits(int fd, int use_pack_protocol)
+int write_shallow_commits(struct strbuf *out, int use_pack_protocol)
 {
 	int i, count = 0;
 	for (i = 0; i < commit_graft_nr; i++)
@@ -208,12 +208,10 @@ int write_shallow_commits(int fd, int use_pack_protocol)
 				sha1_to_hex(commit_graft[i]->sha1);
 			count++;
 			if (use_pack_protocol)
-				packet_write(fd, "shallow %s", hex);
+				packet_buf_write(out, "shallow %s", hex);
 			else {
-				if (write_in_full(fd, hex,  40) != 40)
-					break;
-				if (write_str_in_full(fd, "\n") != 1)
-					break;
+				strbuf_addstr(out, hex);
+				strbuf_addch(out, '\n');
 			}
 		}
 	return count;
diff --git a/commit.h b/commit.h
index f4fc5c5..817c75c 100644
--- a/commit.h
+++ b/commit.h
@@ -131,7 +131,7 @@ extern struct commit_list *get_octopus_merge_bases(struct commit_list *in);
 
 extern int register_shallow(const unsigned char *sha1);
 extern int unregister_shallow(const unsigned char *sha1);
-extern int write_shallow_commits(int fd, int use_pack_protocol);
+extern int write_shallow_commits(struct strbuf *out, int use_pack_protocol);
 extern int is_repository_shallow(void);
 extern struct commit_list *get_shallow_commits(struct object_array *heads,
 		int depth, int shallow_flag, int not_shallow_flag);
-- 
1.6.5.52.g0ff2e
Previous: Shawn O. PearceNext: Shawn O. Pearce
Message 6 of 38 in “Return of smart HTTP”
  1. 00/16 Return of smart HTTPShawn O. Pearce, Oct 13, 2009
  2. 01/16 pkt-line: Add strbuf based functionsShawn O. Pearce, Oct 13, 2009
  3. Johannes SixtOct 13, 2009
  4. Shawn O. PearceOct 13, 2009
  5. 02/16 pkt-line: Make packet_read_line easier to debugShawn O. Pearce, Oct 13, 2009
  6. 03/16 fetch-pack: Use a strbuf to compose the want listShawn O. Pearce, Oct 13, 2009
  7. 04/16 Move "get_ack()" back to fetch-packShawn O. Pearce, Oct 13, 2009
  8. 05/16 Add multi_ack_2 capability to fetch-pack/upload-packShawn O. Pearce, Oct 13, 2009
  9. Jakub NarebskiOct 13, 2009
  10. Shawn O. PearceOct 13, 2009
  11. 06/16 remote-curl: Refactor walker initializationShawn O. Pearce, Oct 13, 2009
  12. 07/16 remote-helpers: Fetch more than one ref in a batchShawn O. Pearce, Oct 13, 2009
  13. Daniel BarkalowOct 13, 2009
  14. Shawn O. PearceOct 13, 2009
  15. 08/16 remote-helpers: Support custom transport optionsShawn O. Pearce, Oct 13, 2009
  16. Daniel BarkalowOct 13, 2009
  17. Shawn O. PearceOct 13, 2009
  18. Daniel BarkalowOct 13, 2009
  19. Shawn O. PearceOct 13, 2009
  20. Daniel BarkalowOct 13, 2009
  21. Shawn O. PearceOct 13, 2009
  22. 09/16 Move WebDAV HTTP push under remote-curlShawn O. Pearce, Oct 13, 2009
  23. Mike HommeyOct 13, 2009
  24. Johannes SchindelinOct 13, 2009
  25. 10/16 Git-aware CGI to provide dumb HTTP transportShawn O. Pearce, Oct 13, 2009
  26. Johannes SixtOct 13, 2009
  27. 11/16 Add one shot RPC options to upload-pack, receive-packShawn O. Pearce, Oct 13, 2009
  28. 12/16 Smart fetch and push over HTTP: server sideShawn O. Pearce, Oct 13, 2009
  29. Johannes SixtOct 13, 2009
  30. Shawn O. PearceOct 13, 2009
  31. 13/16 Discover refs via smart HTTP server when availableShawn O. Pearce, Oct 13, 2009
  32. 14/16 Smart push over HTTP: client sideShawn O. Pearce, Oct 13, 2009
  33. Felipe ContrerasOct 13, 2009
  34. 15/16 Smart fetch over HTTP: client sideShawn O. Pearce, Oct 13, 2009
  35. 16/16 Smart HTTP fetch: gzip requestsShawn O. Pearce, Oct 13, 2009
  36. Junio C HamanoOct 13, 2009
  37. eduard stefanOct 13, 2009
  38. Junio C HamanoOct 13, 2009

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