repo-config: deconvolute logics
[git.git] / fetch-pack.c
index 57602b9..a3bcad0 100644 (file)
@@ -3,71 +3,78 @@
 #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 | COMMON)
+#define COMMON_REF     (1U << 2)
 #define SEEN           (1U << 3)
 #define POPPED         (1U << 4)
 
 static struct commit_list *rev_list = NULL;
-static struct commit_list *rev_list_end = NULL;
-static unsigned long non_common_revs = 0;
+static int non_common_revs = 0, multi_ack = 0, use_thin_pack = 0;
 
-static void rev_list_append(struct commit *commit, int mark)
+static void rev_list_push(struct commit *commit, int mark)
 {
        if (!(commit->object.flags & mark)) {
                commit->object.flags |= mark;
 
-               if (rev_list == NULL) {
-                       commit_list_insert(commit, &rev_list);
-                       rev_list_end = rev_list;
-               } else {
-                       commit_list_insert(commit, &(rev_list_end->next));
-                       rev_list_end = rev_list_end->next;
-               }
+               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_append_sha1(const char *path, const unsigned char *sha1)
+static int rev_list_insert_ref(const char *path, const unsigned char *sha1)
 {
-       struct object *o = deref_tag(parse_object(sha1));
+       struct object *o = deref_tag(parse_object(sha1), path, 0);
 
-       if (o->type == commit_type)
-               rev_list_append((struct commit *)o, SEEN);
+       if (o && o->type == commit_type)
+               rev_list_push((struct commit *)o, SEEN);
 
        return 0;
 }
 
-static void mark_common(struct commit *commit)
+/*
+   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;
-               o->flags |= COMMON;
+
+               if (!ancestors_only)
+                       o->flags |= COMMON;
+
                if (!(o->flags & SEEN))
-                       rev_list_append(commit, SEEN);
+                       rev_list_push(commit, SEEN);
                else {
                        struct commit_list *parents;
 
-                       if (!(o->flags & POPPED))
+                       if (!ancestors_only && !(o->flags & POPPED))
                                non_common_revs--;
-                       if (!o->parsed)
+                       if (!o->parsed && !dont_parse)
                                parse_commit(commit);
+
                        for (parents = commit->parents;
                                        parents;
                                        parents = parents->next)
-                               mark_common(parents->item);
+                               mark_common(parents->item, 0, dont_parse);
                }
        }
 }
@@ -76,7 +83,7 @@ static void mark_common(struct commit *commit)
   Get the next rev to send, ignoring the common.
 */
 
-static const unsigned char* get_rev()
+static const unsigned char* get_rev(void)
 {
        struct commit *commit = NULL;
 
@@ -108,10 +115,10 @@ static const unsigned char* get_rev()
                        mark = SEEN;
 
                while (parents) {
+                       if (!(parents->item->object.flags & SEEN))
+                               rev_list_push(parents->item, mark);
                        if (mark & COMMON)
-                               mark_common(parents->item);
-                       else
-                               rev_list_append(parents->item, mark);
+                               mark_common(parents->item, 1, 0);
                        parents = parents->next;
                }
 
@@ -125,10 +132,10 @@ static int find_common(int fd[2], unsigned char *result_sha1,
                       struct ref *refs)
 {
        int fetching;
-       int count = 0, flushes = 0, multi_ack = 0, retval;
+       int count = 0, flushes = 0, retval;
        const unsigned char *sha1;
 
-       for_each_ref(rev_list_append_sha1);
+       for_each_ref(rev_list_insert_ref);
 
        fetching = 0;
        for ( ; refs ; refs = refs->next) {
@@ -146,17 +153,13 @@ static int find_common(int fd[2], unsigned char *result_sha1,
                 * reachable and we have already scanned it.
                 */
                if (((o = lookup_object(remote)) != NULL) &&
-                   (o->flags & COMPLETE)) {
-                       o = deref_tag(o);
-
-                       if (o->type == commit_type)
-                               rev_list_append((struct commit *)o,
-                                               COMMON_REF | SEEN);
-
+                               (o->flags & COMPLETE)) {
                        continue;
                }
 
-               packet_write(fd[1], "want %s multi_ack\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]);
@@ -188,38 +191,37 @@ static int find_common(int fd[2], unsigned char *result_sha1,
                                        fprintf(stderr, "got ack %d %s\n", ack,
                                                        sha1_to_hex(result_sha1));
                                if (ack == 1) {
-                                       if (!multi_ack)
-                                               flushes = 0;
+                                       flushes = 0;
+                                       multi_ack = 0;
                                        retval = 0;
                                        goto done;
                                } else if (ack == 2) {
-                                       multi_ack = 1;
-                                       mark_common((struct commit *)
-                                                       lookup_object(result_sha1));
+                                       struct commit *commit =
+                                               lookup_commit(result_sha1);
+                                       mark_common(commit, 0, 1);
                                        retval = 0;
                                }
-                       } while(ack);
+                       } while (ack);
                        flushes--;
                }
        }
 done:
-       if (multi_ack) {
-               packet_flush(fd[1]);
-               flushes++;
-       }
        packet_write(fd[1], "done\n");
        if (verbose)
                fprintf(stderr, "done\n");
-       if (retval != 0)
+       if (retval != 0) {
+               multi_ack = 0;
                flushes++;
-       while (flushes) {
-               if (get_ack(fd[0], result_sha1)) {
+       }
+       while (flushes || multi_ack) {
+               int ack = get_ack(fd[0], result_sha1);
+               if (ack) {
                        if (verbose)
-                               fprintf(stderr, "got ack %s\n",
+                               fprintf(stderr, "got ack (%d) %s\n", ack,
                                        sha1_to_hex(result_sha1));
-                       if (!multi_ack)
+                       if (ack == 1)
                                return 0;
-                       retval = 0;
+                       multi_ack = 1;
                        continue;
                }
                flushes--;
@@ -258,7 +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;
@@ -267,7 +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);
@@ -289,28 +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;
 }
@@ -320,53 +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)
@@ -376,6 +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++) {
@@ -386,10 +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;
@@ -403,6 +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;
@@ -410,5 +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;
 }