git-send-pack: actually send the object pack

diff --git a/receive-pack.c b/receive-pack.c
index 13d0b668f0a2103cf753ffd519dcaf53f7291341..7ce5f1e24a57f673e614c6bb3d75480e272d37da 100644 (file)
--- a/receive-pack.c
+++ b/receive-pack.c
@@ -77,6 +77,8 @@ static void write_head_info(const char *base, int nr, char **match)
                        }
                        if (read_ref(path, sha1) < 0)
                                continue;
+                       if (!has_sha1_file(sha1))
+                               continue;
                        if (nr && !path_match(path, nr, match))
                                continue;
                        show_ref(path, sha1);
@@ -86,12 +88,69 @@ static void write_head_info(const char *base, int nr, char **match)
        }
 }
 
-struct line {
-       struct line *next;
-       char data[0];
+struct command {
+       struct command *next;
+       unsigned char old_sha1[20];
+       unsigned char new_sha1[20];
+       char ref_name[0];
 };
 
-struct line *commands = NULL;
+struct command *commands = NULL;
+
+static int verify_old_ref(const char *name, char *hex_contents)
+{
+       int fd, ret;
+       char buffer[60];
+
+       fd = open(name, O_RDONLY);
+       if (fd < 0)
+               return -1;
+       ret = read(fd, buffer, 40);
+       close(fd);
+       if (ret != 40)
+               return -1;
+       if (memcmp(buffer, hex_contents, 40))
+               return -1;
+       return 0;
+}
+
+static void update(const char *name, unsigned char *old_sha1, unsigned char *new_sha1)
+{
+       char new_hex[60], *old_hex, *lock_name;
+       int newfd, namelen, written;
+
+       namelen = strlen(name);
+       lock_name = xmalloc(namelen + 10);
+       memcpy(lock_name, name, namelen);
+       memcpy(lock_name + namelen, ".lock", 6);
+
+       strcpy(new_hex, sha1_to_hex(new_sha1));
+       new_hex[40] = '\n';
+       new_hex[41] = 0;
+       old_hex = sha1_to_hex(old_sha1);
+       if (!has_sha1_file(new_sha1))
+               die("unpack should have generated %s, but I can't find it!", new_hex);
+
+       newfd = open(lock_name, O_CREAT | O_EXCL | O_WRONLY, 0644);
+       if (newfd < 0)
+               die("unable to create %s (%s)", lock_name, strerror(errno));
+       written = write(newfd, new_hex, 41);
+       close(newfd);
+       if (written != 41) {
+               unlink(lock_name);
+               die("unable to write %s", lock_name);
+       }
+       if (verify_old_ref(name, old_hex) < 0) {
+               unlink(lock_name);
+               die("%s changed during push", name);
+       }
+       if (rename(lock_name, name) < 0) {
+               unlink(lock_name);
+               die("unable to replace %s", name);
+       }
+       fprintf(stderr, "%s: %s -> %s\n", name, old_hex, new_hex);
+}
+
 
 /*
  * This gets called after(if) we've successfully
@@ -99,28 +158,41 @@ struct line *commands = NULL;
  */
 static void execute_commands(void)
 {
-       struct line *line = commands;
+       struct command *cmd = commands;
 
-       while (line) {
-               fprintf(stderr, "%s", line->data);
-               line = line->next;
+       while (cmd) {
+               update(cmd->ref_name, cmd->old_sha1, cmd->new_sha1);
+               cmd = cmd->next;
        }
 }
 
 static void read_head_info(void)
 {
-       struct line **p = &commands;
+       struct command **p = &commands;
        for (;;) {
                static char line[1000];
-               int len = packet_read_line(0, line, sizeof(line));
-               struct line *n;
+               unsigned char old_sha1[20], new_sha1[20];
+               struct command *cmd;
+               int len;
+
+               len = packet_read_line(0, line, sizeof(line));
                if (!len)
                        break;
-               n = xmalloc(sizeof(struct line) + len);
-               n->next = NULL;
-               memcpy(n->data, line + 4, len - 3);
-               *p = n;
-               p = &n->next;
+               if (line[len-1] == '\n')
+                       line[--len] = 0;
+               if (len < 83 ||
+                   line[40] != ' ' ||
+                   line[81] != ' ' ||
+                   get_sha1_hex(line, old_sha1) ||
+                   get_sha1_hex(line + 41, new_sha1))
+                       die("protocol error: expected old/new/ref, got '%s'", line);
+               cmd = xmalloc(sizeof(struct command) + len - 80);
+               memcpy(cmd->old_sha1, old_sha1, 20);
+               memcpy(cmd->new_sha1, new_sha1, 20);
+               memcpy(cmd->ref_name, line + 82, len - 81);
+               cmd->next = NULL;
+               *p = cmd;
+               p = &cmd->next;
        }
 }
 
@@ -131,7 +203,6 @@ static void unpack(void)
        if (pid < 0)
                die("unpack fork failed");
        if (!pid) {
-               setenv("GIT_DIR", ".", 1);
                execlp(unpacker, unpacker, NULL);
                die("unpack execute failed");
        }
@@ -194,6 +265,7 @@ int main(int argc, char **argv)
 
        /* If we have a ".git" directory, chdir to it */
        chdir(".git");
+       setenv("GIT_DIR", ".", 1);
 
        if (access("objects", X_OK) < 0 || access("refs/heads", X_OK) < 0)
                die("%s doesn't appear to be a git directory", dir);
@@ -203,7 +275,9 @@ int main(int argc, char **argv)
        packet_flush(1);
 
        read_head_info();
-       unpack();
-       execute_commands();
+       if (commands) {
+               unpack();
+               execute_commands();
+       }
        return 0;
 }