git-upload-pack: Support the multi_ack protocol

[git.git] / upload-pack.c

diff --git a/upload-pack.c b/upload-pack.c
index 878254d..686445e 100644 (file)
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -3,14 +3,16 @@
 #include "pkt-line.h"
 #include "tag.h"
 #include "object.h"
+#include "commit.h"
 
 static const char upload_pack_usage[] = "git-upload-pack [--strict] [--timeout=nn] <dir>";
 
+#define THEY_HAVE (1U << 0)
 #define OUR_REF (1U << 1)
 #define WANTED (1U << 2)
 #define MAX_HAS 256
 #define MAX_NEEDS 256
-static int nr_has = 0, nr_needs = 0, nr_our_refs = 0;
+static int nr_has = 0, nr_needs = 0, multi_ack = 0, nr_our_refs = 0;
 static unsigned char has_sha1[MAX_HAS][20];
 static unsigned char needs_sha1[MAX_NEEDS][20];
 static unsigned int timeout = 0;
@@ -89,15 +91,27 @@ static void create_pack_file(void)
 
 static int got_sha1(char *hex, unsigned char *sha1)
 {
-       int nr;
        if (get_sha1_hex(hex, sha1))
                die("git-upload-pack: expected SHA1 object, got '%s'", hex);
        if (!has_sha1_file(sha1))
                return 0;
-       nr = nr_has;
-       if (nr < MAX_HAS) {
-               memcpy(has_sha1[nr], sha1, 20);
-               nr_has = nr+1;
+       if (nr_has < MAX_HAS) {
+               struct object *o = lookup_object(sha1);
+               if (!(o && o->parsed))
+                       o = parse_object(sha1);
+               if (!o)
+                       die("oops (%s)", sha1_to_hex(sha1));
+               if (o->type == commit_type) {
+                       struct commit_list *parents;
+                       if (o->flags & THEY_HAVE)
+                               return 0;
+                       o->flags |= THEY_HAVE;
+                       for (parents = ((struct commit*)o)->parents;
+                            parents;
+                            parents = parents->next)
+                               parents->item->object.flags |= THEY_HAVE;
+               }
+               memcpy(has_sha1[nr_has++], sha1, 20);
        }
        return 1;
 }
@@ -105,47 +119,47 @@ static int got_sha1(char *hex, unsigned char *sha1)
 static int get_common_commits(void)
 {
        static char line[1000];
-       unsigned char sha1[20];
+       unsigned char sha1[20], last_sha1[20];
        int len;
 
+       track_object_refs = 0;
+       save_commit_buffer = 0;
+
        for(;;) {
                len = packet_read_line(0, line, sizeof(line));
                reset_timeout();
 
                if (!len) {
-                       packet_write(1, "NAK\n");
+                       if (nr_has == 0 || multi_ack)
+                               packet_write(1, "NAK\n");
                        continue;
                }
                len = strip(line, len);
                if (!strncmp(line, "have ", 5)) {
-                       if (got_sha1(line+5, sha1)) {
-                               packet_write(1, "ACK %s\n", sha1_to_hex(sha1));
-                               break;
+                       if (got_sha1(line+5, sha1) &&
+                                       (multi_ack || nr_has == 1)) {
+                               if (nr_has >= MAX_HAS)
+                                       multi_ack = 0;
+                               packet_write(1, "ACK %s%s\n",
+                                       sha1_to_hex(sha1),
+                                       multi_ack ?  " continue" : "");
+                               if (multi_ack)
+                                       memcpy(last_sha1, sha1, 20);
                        }
                        continue;
                }
                if (!strcmp(line, "done")) {
+                       if (nr_has > 0) {
+                               if (multi_ack)
+                                       packet_write(1, "ACK %s\n",
+                                                       sha1_to_hex(last_sha1));
+                               return 0;
+                       }
                        packet_write(1, "NAK\n");
                        return -1;
                }
                die("git-upload-pack: expected SHA1 list, got '%s'", line);
        }
-
-       for (;;) {
-               len = packet_read_line(0, line, sizeof(line));
-               reset_timeout();
-               if (!len)
-                       continue;
-               len = strip(line, len);
-               if (!strncmp(line, "have ", 5)) {
-                       got_sha1(line+5, sha1);
-                       continue;
-               }
-               if (!strcmp(line, "done"))
-                       break;
-               die("git-upload-pack: expected SHA1 list, got '%s'", line);
-       }
-       return 0;
 }
 
 static int receive_needs(void)
@@ -175,6 +189,8 @@ static int receive_needs(void)
                if (strncmp("want ", line, 5) || 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"))
+                       multi_ack = 1;
 
                /* We have sent all our refs already, and the other end
                 * should have chosen out of them; otherwise they are
@@ -196,9 +212,11 @@ static int receive_needs(void)
 
 static int send_ref(const char *refname, const unsigned char *sha1)
 {
+       static char *capabilities = "\0multi_ack";
        struct object *o = parse_object(sha1);
 
-       packet_write(1, "%s %s\n", sha1_to_hex(sha1), refname);
+       packet_write(1, "%s %s%s\n", sha1_to_hex(sha1), refname, capabilities);
+       capabilities = "";
        if (!(o->flags & OUR_REF)) {
                o->flags |= OUR_REF;
                nr_our_refs++;