[PATCH] ssh-protocol version, command types, response code

This patch makes an incompatible change to the protocol used by
rpull/rpush which will let it be extended in the future without
incompatible changes.

Signed-off-by: Daniel Barkalow <barkalow@iabervon.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/rpull.c b/rpull.c
index 8b3322f..f4ab898 100644 (file)
--- a/rpull.c
+++ b/rpull.c
@@ -6,16 +6,39 @@
 static int fd_in;
 static int fd_out;
 
+static unsigned char remote_version = 0;
+static unsigned char local_version = 1;
+
 int fetch(unsigned char *sha1)
 {
        int ret;
+       signed char remote;
+       char type = 'o';
+       if (has_sha1_file(sha1))
+               return 0;
+       write(fd_out, &type, 1);
        write(fd_out, sha1, 20);
+       if (read(fd_in, &remote, 1) < 1)
+               return -1;
+       if (remote < 0)
+               return remote;
        ret = write_sha1_from_fd(sha1, fd_in);
        if (!ret)
                pull_say("got %s\n", sha1_to_hex(sha1));
        return ret;
 }
 
+int get_version(void)
+{
+       char type = 'v';
+       write(fd_out, &type, 1);
+       write(fd_out, &local_version, 1);
+       if (read(fd_in, &remote_version, 1) < 1) {
+               return error("Couldn't read version from remote end");
+       }
+       return 0;
+}
+
 int main(int argc, char **argv)
 {
        char *commit_id;
@@ -48,6 +71,9 @@ int main(int argc, char **argv)
        if (setup_connection(&fd_in, &fd_out, "git-rpush", url, arg, argv + 1))
                return 1;
 
+       if (get_version())
+               return 1;
+
        if (pull(commit_id))
                return 1;
 

diff --git a/rpush.c b/rpush.c
index 17d5ab8..bd381ac 100644 (file)
--- a/rpush.c
+++ b/rpush.c
@@ -3,46 +3,81 @@
 #include <sys/socket.h>
 #include <errno.h>
 
-static void service(int fd_in, int fd_out) {
+unsigned char local_version = 1;
+unsigned char remote_version = 0;
+
+int serve_object(int fd_in, int fd_out) {
        ssize_t size;
-       int posn;
-       char unsigned sha1[20];
+       int posn = 0;
+       char sha1[20];
        unsigned long objsize;
        void *buf;
+       signed char remote;
+       do {
+               size = read(fd_in, sha1 + posn, 20 - posn);
+               if (size < 0) {
+                       perror("git-rpush: read ");
+                       return -1;
+               }
+               if (!size)
+                       return -1;
+               posn += size;
+       } while (posn < 20);
+       
+       /* fprintf(stderr, "Serving %s\n", sha1_to_hex(sha1)); */
+       remote = 0;
+       
+       buf = map_sha1_file(sha1, &objsize);
+       
+       if (!buf) {
+               fprintf(stderr, "git-rpush: could not find %s\n", 
+                       sha1_to_hex(sha1));
+               remote = -1;
+       }
+       
+       write(fd_out, &remote, 1);
+       
+       if (remote < 0)
+               return 0;
+       
+       posn = 0;
        do {
-               posn = 0;
-               do {
-                       size = read(fd_in, sha1 + posn, 20 - posn);
-                       if (size < 0) {
-                               perror("git-rpush: read ");
-                               return;
+               size = write(fd_out, buf + posn, objsize - posn);
+               if (size <= 0) {
+                       if (!size) {
+                               fprintf(stderr, "git-rpush: write closed");
+                       } else {
+                               perror("git-rpush: write ");
                        }
-                       if (!size)
-                               return;
-                       posn += size;
-               } while (posn < 20);
+                       return -1;
+               }
+               posn += size;
+       } while (posn < objsize);
+       return 0;
+}
 
-               /* fprintf(stderr, "Serving %s\n", sha1_to_hex(sha1)); */
+int serve_version(int fd_in, int fd_out)
+{
+       if (read(fd_in, &remote_version, 1) < 1)
+               return -1;
+       write(fd_out, &local_version, 1);
+       return 0;
+}
 
-               buf = map_sha1_file(sha1, &objsize);
-               if (!buf) {
-                       fprintf(stderr, "git-rpush: could not find %s\n", 
-                               sha1_to_hex(sha1));
+void service(int fd_in, int fd_out) {
+       char type;
+       int retval;
+       do {
+               retval = read(fd_in, &type, 1);
+               if (retval < 1) {
+                       if (retval < 0)
+                               perror("rpush: read ");
                        return;
                }
-               posn = 0;
-               do {
-                       size = write(fd_out, buf + posn, objsize - posn);
-                       if (size <= 0) {
-                               if (!size) {
-                                       fprintf(stderr, "git-rpush: write closed");
-                               } else {
-                                       perror("git-rpush: write ");
-                               }
-                               return;
-                       }
-                       posn += size;
-               } while (posn < objsize);
+               if (type == 'v' && serve_version(fd_in, fd_out))
+                       return;
+               if (type == 'o' && serve_object(fd_in, fd_out))
+                       return;
        } while (1);
 }
 
@@ -56,7 +91,7 @@ int main(int argc, char **argv)
                 arg++;
         }
         if (argc < arg + 2) {
-                usage("git-rpush [-c] [-t] [-a] commit-id url");
+               usage("git-rpush [-c] [-t] [-a] commit-id url");
                 return 1;
         }
        commit_id = argv[arg];