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-rw-r--r--fetch-pack.c476
1 files changed, 476 insertions, 0 deletions
diff --git a/fetch-pack.c b/fetch-pack.c
new file mode 100644
index 0000000..a3bcad0
--- /dev/null
+++ b/fetch-pack.c
@@ -0,0 +1,476 @@
+#include "cache.h"
+#include "refs.h"
+#include "pkt-line.h"
+#include "commit.h"
+#include "tag.h"
+
+static int keep_pack;
+static int quiet;
+static int verbose;
+static int fetch_all;
+static const char fetch_pack_usage[] =
+"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;
+ int count = 0, flushes = 0, retval;
+ const unsigned char *sha1;
+
+ for_each_ref(rev_list_insert_ref);
+
+ 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 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%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;
+
+ flushes = 0;
+ retval = -1;
+ 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++;
+
+ /*
+ * We keep one window "ahead" of the other side, and
+ * will wait for an ACK only on the next one
+ */
+ if (count == 32)
+ continue;
+
+ 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--;
+ }
+ }
+done:
+ packet_write(fd[1], "done\n");
+ if (verbose)
+ fprintf(stderr, "done\n");
+ 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 (%d) %s\n", ack,
+ sha1_to_hex(result_sha1));
+ if (ack == 1)
+ return 0;
+ multi_ack = 1;
+ continue;
+ }
+ flushes--;
+ }
+ return retval;
+}
+
+static struct commit_list *complete = NULL;
+
+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(t->tagged->sha1);
+ }
+ if (o && o->type == commit_type) {
+ struct commit *commit = (struct commit *)o;
+ commit->object.flags |= COMPLETE;
+ insert_by_date(commit, &complete);
+ }
+ return 0;
+}
+
+static void mark_recent_complete_commits(unsigned long cutoff)
+{
+ while (complete && cutoff <= complete->item->date) {
+ if (verbose)
+ fprintf(stderr, "Marking %s as complete\n",
+ sha1_to_hex(complete->item->object.sha1));
+ pop_most_recent_commit(&complete, COMPLETE);
+ }
+}
+
+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;
+ unsigned long cutoff = 0;
+
+ track_object_refs = 0;
+ save_commit_buffer = 0;
+
+ for (ref = *refs; ref; ref = ref->next) {
+ struct object *o;
+
+ o = parse_object(ref->old_sha1);
+ if (!o)
+ continue;
+
+ /* We already have it -- which may mean that we were
+ * in sync with the other side at some time after
+ * that (it is OK if we guess wrong here).
+ */
+ if (o->type == commit_type) {
+ struct commit *commit = (struct commit *)o;
+ if (!cutoff || cutoff < commit->date)
+ cutoff = commit->date;
+ }
+ }
+
+ for_each_ref(mark_complete);
+ if (cutoff)
+ mark_recent_complete_commits(cutoff);
+
+ /*
+ * 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 = lookup_object(remote);
+ if (!o || !(o->flags & COMPLETE)) {
+ retval = 0;
+ if (!verbose)
+ continue;
+ fprintf(stderr,
+ "want %s (%s)\n", sha1_to_hex(remote),
+ ref->name);
+ continue;
+ }
+
+ memcpy(ref->new_sha1, local, 20);
+ if (!verbose)
+ continue;
+ fprintf(stderr,
+ "already have %s (%s)\n", sha1_to_hex(remote),
+ ref->name);
+ }
+ return retval;
+}
+
+static int fetch_pack(int fd[2], int nr_match, char **match)
+{
+ struct ref *ref;
+ unsigned char sha1[20];
+ int status;
+
+ 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, nr_match, match)) {
+ packet_flush(fd[1]);
+ goto all_done;
+ }
+ if (find_common(fd, sha1, ref) < 0)
+ 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;
+ }
+ return 0;
+}
+
+int main(int argc, char **argv)
+{
+ int i, ret, nr_heads;
+ char *dest = NULL, **heads;
+ int fd[2];
+ pid_t pid;
+
+ setup_git_directory();
+
+ nr_heads = 0;
+ heads = NULL;
+ for (i = 1; i < argc; i++) {
+ char *arg = argv[i];
+
+ if (*arg == '-') {
+ if (!strncmp("--exec=", arg, 7)) {
+ exec = arg + 7;
+ continue;
+ }
+ 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;
+ }
+ usage(fetch_pack_usage);
+ }
+ dest = arg;
+ heads = argv + i + 1;
+ nr_heads = argc - i - 1;
+ break;
+ }
+ if (!dest)
+ usage(fetch_pack_usage);
+ if (keep_pack)
+ use_thin_pack = 0;
+ pid = git_connect(fd, dest, exec);
+ if (pid < 0)
+ return 1;
+ ret = fetch_pack(fd, nr_heads, heads);
+ 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;
+}