[PATCH] Documentation: describe short-hand used in fetch/pull.
[gitweb.git] / send-pack.c
index f8163b7cbb2c1a279fea8419fcc551b49358434d..02d1d52c2475759f2b206912bbd626f749a6b750 100644 (file)
@@ -1,9 +1,9 @@
 #include "cache.h"
+#include "refs.h"
 #include "pkt-line.h"
-#include <sys/wait.h>
-
-static const char send_pack_usage[] = "git-send-pack [--exec=other] destination [heads]*";
 
+static const char send_pack_usage[] =
+"git-send-pack [--exec=git-receive-pack] [host:]directory [heads]*";
 static const char *exec = "git-receive-pack";
 
 struct ref {
@@ -13,17 +13,105 @@ struct ref {
        char name[0];
 };
 
-static struct ref *ref_list = NULL, **last_ref = &ref_list;
+static int is_zero_sha1(const unsigned char *sha1)
+{
+       int i;
+
+       for (i = 0; i < 20; i++) {
+               if (*sha1++)
+                       return 0;
+       }
+       return 1;
+}
+
+static void exec_pack_objects(void)
+{
+       static char *args[] = {
+               "git-pack-objects",
+               "--stdout",
+               NULL
+       };
+       execvp("git-pack-objects", args);
+       die("git-pack-objects exec failed (%s)", strerror(errno));
+}
+
+static void exec_rev_list(struct ref *refs)
+{
+       static char *args[1000];
+       int i = 0;
+
+       args[i++] = "git-rev-list";     /* 0 */
+       args[i++] = "--objects";        /* 1 */
+       while (refs) {
+               char *buf = malloc(100);
+               if (i > 900)
+                       die("git-rev-list environment overflow");
+               if (!is_zero_sha1(refs->old_sha1)) {
+                       args[i++] = buf;
+                       snprintf(buf, 50, "^%s", sha1_to_hex(refs->old_sha1));
+                       buf += 50;
+               }
+               if (!is_zero_sha1(refs->new_sha1)) {
+                       args[i++] = buf;
+                       snprintf(buf, 50, "%s", sha1_to_hex(refs->new_sha1));
+               }
+               refs = refs->next;
+       }
+       args[i] = NULL;
+       execvp("git-rev-list", args);
+       die("git-rev-list exec failed (%s)", strerror(errno));
+}
+
+static void rev_list(int fd, struct ref *refs)
+{
+       int pipe_fd[2];
+       pid_t pack_objects_pid;
+
+       if (pipe(pipe_fd) < 0)
+               die("rev-list setup: pipe failed");
+       pack_objects_pid = fork();
+       if (!pack_objects_pid) {
+               dup2(pipe_fd[0], 0);
+               dup2(fd, 1);
+               close(pipe_fd[0]);
+               close(pipe_fd[1]);
+               close(fd);
+               exec_pack_objects();
+               die("pack-objects setup failed");
+       }
+       if (pack_objects_pid < 0)
+               die("pack-objects fork failed");
+       dup2(pipe_fd[1], 1);
+       close(pipe_fd[0]);
+       close(pipe_fd[1]);
+       close(fd);
+       exec_rev_list(refs);
+}
+
+static int pack_objects(int fd, struct ref *refs)
+{
+       pid_t rev_list_pid;
+
+       rev_list_pid = fork();
+       if (!rev_list_pid) {
+               rev_list(fd, refs);
+               die("rev-list setup failed");
+       }
+       if (rev_list_pid < 0)
+               die("rev-list fork failed");
+       /*
+        * We don't wait for the rev-list pipeline in the parent:
+        * we end up waiting for the other end instead
+        */
+       return 0;
+}
 
 static int read_ref(const char *ref, unsigned char *sha1)
 {
        int fd, ret;
-       static char pathname[PATH_MAX];
        char buffer[60];
-       const char *git_dir = gitenv(GIT_DIR_ENVIRONMENT) ? : DEFAULT_GIT_DIR_ENVIRONMENT;
 
-       snprintf(pathname, sizeof(pathname), "%s/%s", git_dir, ref);
-       fd = open(pathname, O_RDONLY);
+       fd = open(git_path("%s", ref), O_RDONLY);
        if (fd < 0)
                return -1;
        ret = -1;
@@ -33,13 +121,54 @@ static int read_ref(const char *ref, unsigned char *sha1)
        return ret;
 }
 
-static int send_pack(int in, int out)
+static int ref_newer(const unsigned char *new_sha1, const unsigned char *old_sha1)
+{
+       if (!has_sha1_file(old_sha1))
+               return 0;
+       /*
+        * FIXME! It is not correct to say that the new one is newer
+        * just because we don't have the old one!
+        *
+        * We should really see if we can reach the old_sha1 commit
+        * from the new_sha1 one.
+        */
+       return 1;
+}
+
+static int local_ref_nr_match;
+static char **local_ref_match;
+static struct ref **local_ref_list;
+
+static int try_to_match(const char *refname, const unsigned char *sha1)
+{
+       struct ref *ref;
+       int len;
+
+       if (!path_match(refname, local_ref_nr_match, local_ref_match))
+               return 0;
+
+       len = strlen(refname)+1;
+       ref = xmalloc(sizeof(*ref) + len);
+       memset(ref->old_sha1, 0, 20);
+       memcpy(ref->new_sha1, sha1, 20);
+       memcpy(ref->name, refname, len);
+       ref->next = NULL;
+       *local_ref_list = ref;
+       local_ref_list = &ref->next;
+       return 0;
+}
+
+static int send_pack(int in, int out, int nr_match, char **match)
 {
+       struct ref *ref_list = NULL, **last_ref = &ref_list;
        struct ref *ref;
+       int new_refs;
 
+       /*
+        * Read all the refs from the other end
+        */
        for (;;) {
                unsigned char old_sha1[20];
-               unsigned char new_sha1[20];
                static char buffer[1000];
                char *name;
                int len;
@@ -53,25 +182,62 @@ static int send_pack(int in, int out)
                if (len < 42 || get_sha1_hex(buffer, old_sha1) || buffer[40] != ' ')
                        die("protocol error: expected sha/ref, got '%s'", buffer);
                name = buffer + 41;
-               if (read_ref(name, new_sha1) < 0)
-                       return error("no such local reference '%s'", name);
-               if (!has_sha1_file(old_sha1))
-                       return error("remote '%s' points to object I don't have", name);
-               if (!memcmp(old_sha1, new_sha1, 20)) {
-                       fprintf(stderr, "'%s' unchanged\n", name);
-                       continue;
-               }
                ref = xmalloc(sizeof(*ref) + len - 40);
                memcpy(ref->old_sha1, old_sha1, 20);
-               memcpy(ref->new_sha1, new_sha1, 20);
+               memset(ref->new_sha1, 0, 20);
                memcpy(ref->name, buffer + 41, len - 40);
                ref->next = NULL;
                *last_ref = ref;
                last_ref = &ref->next;
        }
 
+       /*
+        * Go through the refs, see if we want to update
+        * any of them..
+        */
+       for (ref = ref_list; ref; ref = ref->next) {
+               unsigned char new_sha1[20];
+               char *name = ref->name;
+
+               if (nr_match && !path_match(name, nr_match, match))
+                       continue;
+
+               if (read_ref(name, new_sha1) < 0)
+                       continue;
+
+               if (!memcmp(ref->old_sha1, new_sha1, 20)) {
+                       fprintf(stderr, "'%s' unchanged\n", name);
+                       continue;
+               }
+
+               if (!ref_newer(new_sha1, ref->old_sha1)) {
+                       error("remote '%s' points to object I don't have", name);
+                       continue;
+               }
+
+               /* Ok, mark it for update */
+               memcpy(ref->new_sha1, new_sha1, 20);
+       }
+
+       /*
+        * See if we have any refs that the other end didn't have
+        */
+       if (nr_match) {
+               local_ref_nr_match = nr_match;
+               local_ref_match = match;
+               local_ref_list = last_ref;
+               for_each_ref(try_to_match);
+       }
+
+       /*
+        * Finally, tell the other end!
+        */
+       new_refs = 0;
        for (ref = ref_list; ref; ref = ref->next) {
                char old_hex[60], *new_hex;
+               if (is_zero_sha1(ref->new_sha1))
+                       continue;
+               new_refs++;
                strcpy(old_hex, sha1_to_hex(ref->old_sha1));
                new_hex = sha1_to_hex(ref->new_sha1);
                packet_write(out, "%s %s %s", old_hex, new_hex, ref->name);
@@ -79,80 +245,12 @@ static int send_pack(int in, int out)
        }
        
        packet_flush(out);
+       if (new_refs)
+               pack_objects(out, ref_list);
        close(out);
        return 0;
 }
 
-/*
- * First, make it shell-safe.  We do this by just disallowing any
- * special characters. Somebody who cares can do escaping and let
- * through the rest. But since we're doing to feed this to ssh as
- * a command line, we're going to be pretty damn anal for now.
- */
-static char *shell_safe(char *url)
-{
-       char *n = url;
-       unsigned char c;
-       static const char flags[256] = {
-               ['0'...'9'] = 1,
-               ['a'...'z'] = 1,
-               ['A'...'Z'] = 1,
-               ['.'] = 1, ['/'] = 1,
-               ['-'] = 1, ['+'] = 1,
-               [':'] = 1
-       };
-
-       while ((c = *n++) != 0) {
-               if (flags[c] != 1)
-                       die("I don't like '%c'. Sue me.", c);
-       }
-       return url;
-}
-
-/*
- * Yeah, yeah, fixme. Need to pass in the heads etc.
- */
-static int setup_connection(int fd[2], char *url, char **heads)
-{
-       char command[1024];
-       const char *host, *path;
-       char *colon;
-       int pipefd[2][2];
-       pid_t pid;
-
-       url = shell_safe(url);
-       host = NULL;
-       path = url;
-       colon = strchr(url, ':');
-       if (colon) {
-               *colon = 0;
-               host = url;
-               path = colon+1;
-       }
-       snprintf(command, sizeof(command), "%s %s", exec, path);
-       if (pipe(pipefd[0]) < 0 || pipe(pipefd[1]) < 0)
-               die("unable to create pipe pair for communication");
-       pid = fork();
-       if (!pid) {
-               dup2(pipefd[1][0], 0);
-               dup2(pipefd[0][1], 1);
-               close(pipefd[0][0]);
-               close(pipefd[0][1]);
-               close(pipefd[1][0]);
-               close(pipefd[1][1]);
-               if (host)
-                       execlp("ssh", "ssh", host, command, NULL);
-               else
-                       execlp("sh", "sh", "-c", command, NULL);
-               die("exec failed");
-       }               
-       fd[0] = pipefd[0][0];
-       fd[1] = pipefd[1][1];
-       close(pipefd[0][1]);
-       close(pipefd[1][0]);
-       return pid;
-}
-
 int main(int argc, char **argv)
 {
        int i, nr_heads = 0;
@@ -179,12 +277,12 @@ int main(int argc, char **argv)
        }
        if (!dest)
                usage(send_pack_usage);
-       pid = setup_connection(fd, dest, heads);
+       pid = git_connect(fd, dest, exec);
        if (pid < 0)
                return 1;
-       ret = send_pack(fd[0], fd[1]);
+       ret = send_pack(fd[0], fd[1], nr_heads, heads);
        close(fd[0]);
        close(fd[1]);
-       waitpid(pid, NULL, 0);
+       finish_connect(pid);
        return ret;
 }