path: root/upload-pack.c
diff options
authorShawn O. Pearce <>2009-10-31 00:47:25 (GMT)
committerJunio C Hamano <>2009-10-31 02:20:54 (GMT)
commit78affc49ded26700450d25168534af02b29a6c61 (patch)
tree563403d789d2986441ce26ff9162645f83851e7e /upload-pack.c
parent28754ab5f0ce9b4f6ca1641c3e10e2c68bd9b3fc (diff)
Add multi_ack_detailed capability to fetch-pack/upload-pack
When multi_ack_detailed is enabled the ACK continue messages returned by the remote upload-pack are broken out to describe the different states within the peer. This permits the client to better understand the server's in-memory state. The fetch-pack/upload-pack protocol now looks like: NAK --------------------------------- Always sent in response to "done" if there was no common base selected from the "have" lines (or no have lines were sent). * no multi_ack or multi_ack_detailed: Sent when the client has sent a pkt-line flush ("0000") and the server has not yet found a common base object. * either multi_ack or multi_ack_detailed: Always sent in response to a pkt-line flush. ACK %s ----------------------------------- * no multi_ack or multi_ack_detailed: Sent in response to "have" when the object exists on the remote side and is therefore an object in common between the peers. The argument is the SHA-1 of the common object. * either multi_ack or multi_ack_detailed: Sent in response to "done" if there are common objects. The argument is the last SHA-1 determined to be common. ACK %s continue ----------------------------------- * multi_ack only: Sent in response to "have". The remote side wants the client to consider this object as common, and immediately stop transmitting additional "have" lines for objects that are reachable from it. The reason the client should stop is not given, but is one of the two cases below available under multi_ack_detailed. ACK %s common ----------------------------------- * multi_ack_detailed only: Sent in response to "have". Both sides have this object. Like with "ACK %s continue" above the client should stop sending have lines reachable for objects from the argument. ACK %s ready ----------------------------------- * multi_ack_detailed only: Sent in response to "have". The client should stop transmitting objects which are reachable from the argument, and send "done" soon to get the objects. If the remote side has the specified object, it should first send an "ACK %s common" message prior to sending "ACK %s ready". Clients may still submit additional "have" lines if there are more side branches for the client to explore that might be added to the common set and reduce the number of objects to transfer. Signed-off-by: Shawn O. Pearce <> Signed-off-by: Junio C Hamano <>
Diffstat (limited to 'upload-pack.c')
1 files changed, 18 insertions, 13 deletions
diff --git a/upload-pack.c b/upload-pack.c
index 38ddac2..f1dc3a3 100644
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -498,7 +498,7 @@ static int get_common_commits(void)
static char line[1000];
unsigned char sha1[20];
- char hex[41], last_hex[41];
+ char last_hex[41];
save_commit_buffer = 0;
@@ -515,19 +515,22 @@ static int get_common_commits(void)
if (!prefixcmp(line, "have ")) {
switch (got_sha1(line+5, sha1)) {
case -1: /* they have what we do not */
- if (multi_ack && ok_to_give_up())
- packet_write(1, "ACK %s continue\n",
- sha1_to_hex(sha1));
+ if (multi_ack && ok_to_give_up()) {
+ const char *hex = sha1_to_hex(sha1);
+ if (multi_ack == 2)
+ packet_write(1, "ACK %s ready\n", hex);
+ else
+ packet_write(1, "ACK %s continue\n", hex);
+ }
- memcpy(hex, sha1_to_hex(sha1), 41);
- if (multi_ack) {
- const char *msg = "ACK %s continue\n";
- packet_write(1, msg, hex);
- memcpy(last_hex, hex, 41);
- }
+ memcpy(last_hex, sha1_to_hex(sha1), 41);
+ if (multi_ack == 2)
+ packet_write(1, "ACK %s common\n", last_hex);
+ else if (multi_ack)
+ packet_write(1, "ACK %s continue\n", last_hex);
else if ( == 1)
- packet_write(1, "ACK %s\n", hex);
+ packet_write(1, "ACK %s\n", last_hex);
@@ -587,7 +590,9 @@ static void receive_needs(void)
get_sha1_hex(line+5, sha1_buf))
die("git upload-pack: protocol error, "
"expected to get sha, not '%s'", line);
- if (strstr(line+45, "multi_ack"))
+ if (strstr(line+45, "multi_ack_detailed"))
+ multi_ack = 2;
+ else if (strstr(line+45, "multi_ack"))
multi_ack = 1;
if (strstr(line+45, "thin-pack"))
use_thin_pack = 1;
@@ -681,7 +686,7 @@ static int send_ref(const char *refname, const unsigned char *sha1, int flag, vo
static const char *capabilities = "multi_ack thin-pack side-band"
" side-band-64k ofs-delta shallow no-progress"
- " include-tag";
+ " include-tag multi_ack_detailed";
struct object *o = parse_object(sha1);
if (!o)