revision: --max-age alone does not need limit_list() anymore.
[gitweb.git] / fetch-pack.c
index 9dfd072db786a62d7d971a1b98f539e68ec364fc..a3bcad016f52c09897c836112e03eec859a5eb1e 100644 (file)
 #include "pkt-line.h"
 #include "commit.h"
 #include "tag.h"
-#include <time.h>
-#include <sys/wait.h>
 
+static int keep_pack;
 static int quiet;
 static int verbose;
+static int fetch_all;
 static const char fetch_pack_usage[] =
-"git-fetch-pack [-q] [-v] [--exec=upload-pack] [host:]directory <refs>...";
+"git-fetch-pack [--all] [-q] [-v] [-k] [--thin] [--exec=upload-pack] [host:]directory <refs>...";
 static const char *exec = "git-upload-pack";
 
 #define COMPLETE       (1U << 0)
+#define COMMON         (1U << 1)
+#define COMMON_REF     (1U << 2)
+#define SEEN           (1U << 3)
+#define POPPED         (1U << 4)
+
+static struct commit_list *rev_list = NULL;
+static int non_common_revs = 0, multi_ack = 0, use_thin_pack = 0;
+
+static void rev_list_push(struct commit *commit, int mark)
+{
+       if (!(commit->object.flags & mark)) {
+               commit->object.flags |= mark;
+
+               if (!(commit->object.parsed))
+                       parse_commit(commit);
+
+               insert_by_date(commit, &rev_list);
+
+               if (!(commit->object.flags & COMMON))
+                       non_common_revs++;
+       }
+}
+
+static int rev_list_insert_ref(const char *path, const unsigned char *sha1)
+{
+       struct object *o = deref_tag(parse_object(sha1), path, 0);
+
+       if (o && o->type == commit_type)
+               rev_list_push((struct commit *)o, SEEN);
+
+       return 0;
+}
+
+/*
+   This function marks a rev and its ancestors as common.
+   In some cases, it is desirable to mark only the ancestors (for example
+   when only the server does not yet know that they are common).
+*/
+
+static void mark_common(struct commit *commit,
+               int ancestors_only, int dont_parse)
+{
+       if (commit != NULL && !(commit->object.flags & COMMON)) {
+               struct object *o = (struct object *)commit;
+
+               if (!ancestors_only)
+                       o->flags |= COMMON;
+
+               if (!(o->flags & SEEN))
+                       rev_list_push(commit, SEEN);
+               else {
+                       struct commit_list *parents;
+
+                       if (!ancestors_only && !(o->flags & POPPED))
+                               non_common_revs--;
+                       if (!o->parsed && !dont_parse)
+                               parse_commit(commit);
+
+                       for (parents = commit->parents;
+                                       parents;
+                                       parents = parents->next)
+                               mark_common(parents->item, 0, dont_parse);
+               }
+       }
+}
+
+/*
+  Get the next rev to send, ignoring the common.
+*/
+
+static const unsigned char* get_rev(void)
+{
+       struct commit *commit = NULL;
+
+       while (commit == NULL) {
+               unsigned int mark;
+               struct commit_list* parents;
+
+               if (rev_list == NULL || non_common_revs == 0)
+                       return NULL;
+
+               commit = rev_list->item;
+               if (!(commit->object.parsed))
+                       parse_commit(commit);
+               commit->object.flags |= POPPED;
+               if (!(commit->object.flags & COMMON))
+                       non_common_revs--;
+       
+               parents = commit->parents;
+
+               if (commit->object.flags & COMMON) {
+                       /* do not send "have", and ignore ancestors */
+                       commit = NULL;
+                       mark = COMMON | SEEN;
+               } else if (commit->object.flags & COMMON_REF)
+                       /* send "have", and ignore ancestors */
+                       mark = COMMON | SEEN;
+               else
+                       /* send "have", also for its ancestors */
+                       mark = SEEN;
+
+               while (parents) {
+                       if (!(parents->item->object.flags & SEEN))
+                               rev_list_push(parents->item, mark);
+                       if (mark & COMMON)
+                               mark_common(parents->item, 1, 0);
+                       parents = parents->next;
+               }
+
+               rev_list = rev_list->next;
+       }
+
+       return commit->object.sha1;
+}
 
 static int find_common(int fd[2], unsigned char *result_sha1,
                       struct ref *refs)
 {
        int fetching;
-       static char line[1000];
-       static char rev_command[1024];
-       int count = 0, flushes = 0, retval, rev_command_len;
-       FILE *revs;
+       int count = 0, flushes = 0, retval;
+       const unsigned char *sha1;
+
+       for_each_ref(rev_list_insert_ref);
 
-       strcpy(rev_command, "git-rev-list $(git-rev-parse --all)");
-       rev_command_len = strlen(rev_command);
        fetching = 0;
        for ( ; refs ; refs = refs->next) {
                unsigned char *remote = refs->old_sha1;
+               struct object *o;
 
                /*
-                  If that object is complete (i.e. it is a descendant of a
-                  local ref), we don't want it, nor its descendants.
-               */
-               if (has_sha1_file(remote)
-                               && parse_object(remote)->flags & COMPLETE) {
-                       if (rev_command_len + 44 < sizeof(rev_command)) {
-                               snprintf(rev_command + rev_command_len, 44,
-                                       " ^%s^", sha1_to_hex(remote));
-                               rev_command_len += 43;
-                       }
-
+                * If that object is complete (i.e. it is an ancestor of a
+                * local ref), we tell them we have it but do not have to
+                * tell them about its ancestors, which they already know
+                * about.
+                *
+                * We use lookup_object here because we are only
+                * interested in the case we *know* the object is
+                * reachable and we have already scanned it.
+                */
+               if (((o = lookup_object(remote)) != NULL) &&
+                               (o->flags & COMPLETE)) {
                        continue;
                }
 
-               packet_write(fd[1], "want %s\n", sha1_to_hex(remote));
+               packet_write(fd[1], "want %s%s%s\n", sha1_to_hex(remote),
+                            (multi_ack ? " multi_ack" : ""),
+                            (use_thin_pack ? " thin-pack" : ""));
                fetching++;
        }
        packet_flush(fd[1]);
        if (!fetching)
                return 1;
 
-       revs = popen(rev_command, "r");
-       if (!revs)
-               die("unable to run 'git-rev-list'");
-
-       flushes = 1;
+       flushes = 0;
        retval = -1;
-       while (fgets(line, sizeof(line), revs) != NULL) {
-               unsigned char sha1[20];
-               if (get_sha1_hex(line, sha1))
-                       die("git-fetch-pack: expected object name, got crud");
+       while ((sha1 = get_rev())) {
                packet_write(fd[1], "have %s\n", sha1_to_hex(sha1));
                if (verbose)
                        fprintf(stderr, "have %s\n", sha1_to_hex(sha1));
                if (!(31 & ++count)) {
+                       int ack;
+
                        packet_flush(fd[1]);
                        flushes++;
 
@@ -74,27 +184,47 @@ static int find_common(int fd[2], unsigned char *result_sha1,
                         */
                        if (count == 32)
                                continue;
-                       if (get_ack(fd[0], result_sha1)) {
-                               flushes = 0;
-                               retval = 0;
-                               if (verbose)
-                                       fprintf(stderr, "got ack\n");
-                               break;
-                       }
+
+                       do {
+                               ack = get_ack(fd[0], result_sha1);
+                               if (verbose && ack)
+                                       fprintf(stderr, "got ack %d %s\n", ack,
+                                                       sha1_to_hex(result_sha1));
+                               if (ack == 1) {
+                                       flushes = 0;
+                                       multi_ack = 0;
+                                       retval = 0;
+                                       goto done;
+                               } else if (ack == 2) {
+                                       struct commit *commit =
+                                               lookup_commit(result_sha1);
+                                       mark_common(commit, 0, 1);
+                                       retval = 0;
+                               }
+                       } while (ack);
                        flushes--;
                }
        }
-       pclose(revs);
+done:
        packet_write(fd[1], "done\n");
        if (verbose)
                fprintf(stderr, "done\n");
-       while (flushes) {
-               flushes--;
-               if (get_ack(fd[0], result_sha1)) {
+       if (retval != 0) {
+               multi_ack = 0;
+               flushes++;
+       }
+       while (flushes || multi_ack) {
+               int ack = get_ack(fd[0], result_sha1);
+               if (ack) {
                        if (verbose)
-                               fprintf(stderr, "got ack\n");
-                       return 0;
+                               fprintf(stderr, "got ack (%d) %s\n", ack,
+                                       sha1_to_hex(result_sha1));
+                       if (ack == 1)
+                               return 0;
+                       multi_ack = 1;
+                       continue;
                }
+               flushes--;
        }
        return retval;
 }
@@ -106,10 +236,13 @@ static int mark_complete(const char *path, const unsigned char *sha1)
        struct object *o = parse_object(sha1);
 
        while (o && o->type == tag_type) {
+               struct tag *t = (struct tag *) o;
+               if (!t->tagged)
+                       break; /* broken repository */
                o->flags |= COMPLETE;
-               o = parse_object(((struct tag *)o)->tagged->sha1);
+               o = parse_object(t->tagged->sha1);
        }
-       if (o->type == commit_type) {
+       if (o && o->type == commit_type) {
                struct commit *commit = (struct commit *)o;
                commit->object.flags |= COMPLETE;
                insert_by_date(commit, &complete);
@@ -127,7 +260,27 @@ static void mark_recent_complete_commits(unsigned long cutoff)
        }
 }
 
-static int everything_local(struct ref *refs)
+static void filter_refs(struct ref **refs, int nr_match, char **match)
+{
+       struct ref *prev, *current, *next;
+
+       for (prev = NULL, current = *refs; current; current = next) {
+               next = current->next;
+               if ((!memcmp(current->name, "refs/", 5) &&
+                    check_ref_format(current->name + 5)) ||
+                   (!fetch_all &&
+                    !path_match(current->name, nr_match, match))) {
+                       if (prev == NULL)
+                               *refs = next;
+                       else
+                               prev->next = next;
+                       free(current);
+               } else
+                       prev = current;
+       }
+}
+
+static int everything_local(struct ref **refs, int nr_match, char **match)
 {
        struct ref *ref;
        int retval;
@@ -136,7 +289,7 @@ static int everything_local(struct ref *refs)
        track_object_refs = 0;
        save_commit_buffer = 0;
 
-       for (ref = refs; ref; ref = ref->next) {
+       for (ref = *refs; ref; ref = ref->next) {
                struct object *o;
 
                o = parse_object(ref->old_sha1);
@@ -158,28 +311,48 @@ static int everything_local(struct ref *refs)
        if (cutoff)
                mark_recent_complete_commits(cutoff);
 
-       for (retval = 1; refs ; refs = refs->next) {
-               const unsigned char *remote = refs->old_sha1;
+       /*
+        * Mark all complete remote refs as common refs.
+        * Don't mark them common yet; the server has to be told so first.
+        */
+       for (ref = *refs; ref; ref = ref->next) {
+               struct object *o = deref_tag(lookup_object(ref->old_sha1),
+                                            NULL, 0);
+
+               if (!o || o->type != commit_type || !(o->flags & COMPLETE))
+                       continue;
+
+               if (!(o->flags & SEEN)) {
+                       rev_list_push((struct commit *)o, COMMON_REF | SEEN);
+
+                       mark_common((struct commit *)o, 1, 1);
+               }
+       }
+
+       filter_refs(refs, nr_match, match);
+
+       for (retval = 1, ref = *refs; ref ; ref = ref->next) {
+               const unsigned char *remote = ref->old_sha1;
                unsigned char local[20];
                struct object *o;
 
-               o = parse_object(remote);
+               o = lookup_object(remote);
                if (!o || !(o->flags & COMPLETE)) {
                        retval = 0;
                        if (!verbose)
                                continue;
                        fprintf(stderr,
                                "want %s (%s)\n", sha1_to_hex(remote),
-                               refs->name);
+                               ref->name);
                        continue;
                }
 
-               memcpy(refs->new_sha1, local, 20);
+               memcpy(ref->new_sha1, local, 20);
                if (!verbose)
                        continue;
                fprintf(stderr,
                        "already have %s (%s)\n", sha1_to_hex(remote),
-                       refs->name);
+                       ref->name);
        }
        return retval;
 }
@@ -189,53 +362,43 @@ static int fetch_pack(int fd[2], int nr_match, char **match)
        struct ref *ref;
        unsigned char sha1[20];
        int status;
-       pid_t pid;
 
-       get_remote_heads(fd[0], &ref, nr_match, match, 1);
+       get_remote_heads(fd[0], &ref, 0, NULL, 0);
+       if (server_supports("multi_ack")) {
+               if (verbose)
+                       fprintf(stderr, "Server supports multi_ack\n");
+               multi_ack = 1;
+       }
        if (!ref) {
                packet_flush(fd[1]);
                die("no matching remote head");
        }
-       if (everything_local(ref)) {
+       if (everything_local(&ref, nr_match, match)) {
                packet_flush(fd[1]);
                goto all_done;
        }
        if (find_common(fd, sha1, ref) < 0)
-               fprintf(stderr, "warning: no common commits\n");
-       pid = fork();
-       if (pid < 0)
-               die("git-fetch-pack: unable to fork off git-unpack-objects");
-       if (!pid) {
-               dup2(fd[0], 0);
-               close(fd[0]);
-               close(fd[1]);
-               execlp("git-unpack-objects", "git-unpack-objects",
-                      quiet ? "-q" : NULL, NULL);
-               die("git-unpack-objects exec failed");
-       }
-       close(fd[0]);
-       close(fd[1]);
-       while (waitpid(pid, &status, 0) < 0) {
-               if (errno != EINTR)
-                       die("waiting for git-unpack-objects: %s", strerror(errno));
-       }
-       if (WIFEXITED(status)) {
-               int code = WEXITSTATUS(status);
-               if (code)
-                       die("git-unpack-objects died with error code %d", code);
-all_done:
-               while (ref) {
-                       printf("%s %s\n",
-                              sha1_to_hex(ref->old_sha1), ref->name);
-                       ref = ref->next;
-               }
-               return 0;
-       }
-       if (WIFSIGNALED(status)) {
-               int sig = WTERMSIG(status);
-               die("git-unpack-objects died of signal %d", sig);
+               if (!keep_pack)
+                       /* When cloning, it is not unusual to have
+                        * no common commit.
+                        */
+                       fprintf(stderr, "warning: no common commits\n");
+
+       if (keep_pack)
+               status = receive_keep_pack(fd, "git-fetch-pack", quiet);
+       else
+               status = receive_unpack_pack(fd, "git-fetch-pack", quiet);
+
+       if (status)
+               die("git-fetch-pack: fetch failed.");
+
+ all_done:
+       while (ref) {
+               printf("%s %s\n",
+                      sha1_to_hex(ref->old_sha1), ref->name);
+               ref = ref->next;
        }
-       die("Sherlock Holmes! git-unpack-objects died of unnatural causes %d!", status);
+       return 0;
 }
 
 int main(int argc, char **argv)
@@ -245,6 +408,8 @@ int main(int argc, char **argv)
        int fd[2];
        pid_t pid;
 
+       setup_git_directory();
+
        nr_heads = 0;
        heads = NULL;
        for (i = 1; i < argc; i++) {
@@ -255,10 +420,22 @@ int main(int argc, char **argv)
                                exec = arg + 7;
                                continue;
                        }
-                       if (!strcmp("-q", arg)) {
+                       if (!strcmp("--quiet", arg) || !strcmp("-q", arg)) {
                                quiet = 1;
                                continue;
                        }
+                       if (!strcmp("--keep", arg) || !strcmp("-k", arg)) {
+                               keep_pack = 1;
+                               continue;
+                       }
+                       if (!strcmp("--thin", arg)) {
+                               use_thin_pack = 1;
+                               continue;
+                       }
+                       if (!strcmp("--all", arg)) {
+                               fetch_all = 1;
+                               continue;
+                       }
                        if (!strcmp("-v", arg)) {
                                verbose = 1;
                                continue;
@@ -272,6 +449,8 @@ int main(int argc, char **argv)
        }
        if (!dest)
                usage(fetch_pack_usage);
+       if (keep_pack)
+               use_thin_pack = 0;
        pid = git_connect(fd, dest, exec);
        if (pid < 0)
                return 1;
@@ -279,5 +458,19 @@ int main(int argc, char **argv)
        close(fd[0]);
        close(fd[1]);
        finish_connect(pid);
+
+       if (!ret && nr_heads) {
+               /* If the heads to pull were given, we should have
+                * consumed all of them by matching the remote.
+                * Otherwise, 'git-fetch remote no-such-ref' would
+                * silently succeed without issuing an error.
+                */
+               for (i = 0; i < nr_heads; i++)
+                       if (heads[i] && heads[i][0]) {
+                               error("no such remote ref %s", heads[i]);
+                               ret = 1;
+                       }
+       }
+
        return ret;
 }