Make git-fetch-pack and git-upload-pack negotiate needs/haves fully

diff --git a/upload-pack.c b/upload-pack.c
index 18b8e1a6cac99633dddcd5628735a54e1047a712..b454c9e11dbea4d023ec724252e14b4984bfba9b 100644 (file)
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -4,11 +4,37 @@
 
 static const char upload_pack_usage[] = "git-upload-pack <dir>";
 
+#define MAX_HAS (16)
+#define MAX_NEEDS (16)
+static int nr_has = 0, nr_needs = 0;
+static unsigned char has_sha1[MAX_HAS][20];
+static unsigned char needs_sha1[MAX_NEEDS][20];
+
+static void create_pack_file(void)
+{
+       /*
+        * Here, we should do
+        *
+        *      git-rev-list --objects needs_sha1 --not has_sha1 |
+        *              git-pack-objects --stdout
+        *
+        * but we don't.
+        */
+}
+
 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);
-       return has_sha1_file(sha1);
+       if (!has_sha1_file(sha1))
+               return 0;
+       nr = nr_has;
+       if (nr < MAX_HAS) {
+               memcpy(has_sha1[nr], sha1, 20);
+               nr_has = nr+1;
+       }
+       return 1;
 }
 
 static int get_common_commits(void)
@@ -55,6 +81,29 @@ static int get_common_commits(void)
        return 0;
 }
 
+static int receive_needs(void)
+{
+       static char line[1000];
+       int len, needs;
+
+       needs = 0;
+       for (;;) {
+               len = packet_read_line(0, line, sizeof(line));
+               if (!len)
+                       return needs;
+
+               /*
+                * This is purely theoretical right now: git-fetch-pack only
+                * ever asks for a single HEAD
+                */
+               if (needs >= MAX_NEEDS)
+                       die("I'm only doing a max of %d requests", MAX_NEEDS);
+               if (strncmp("want ", line, 5) || get_sha1_hex(line+5, needs_sha1[needs]))
+                       die("git-upload-pack: protocol error, expected to get sha, not '%s'", line);
+               needs++;
+       }
+}
+
 static int send_ref(const char *refname, const unsigned char *sha1)
 {
        packet_write(1, "%s %s\n", sha1_to_hex(sha1), refname);
@@ -65,7 +114,11 @@ static int upload_pack(void)
 {
        for_each_ref(send_ref);
        packet_flush(1);
+       nr_needs = receive_needs();
+       if (!nr_needs)
+               return 0;
        get_common_commits();
+       create_pack_file();
        return 0;
 }