diff options
Diffstat (limited to 'upload-pack.c')
| -rw-r--r-- | upload-pack.c | 692 |
1 files changed, 692 insertions, 0 deletions
diff --git a/upload-pack.c b/upload-pack.c new file mode 100644 index 0000000..d3a09e7 --- /dev/null +++ b/upload-pack.c @@ -0,0 +1,692 @@ +#include "cache.h" +#include "refs.h" +#include "pkt-line.h" +#include "sideband.h" +#include "tag.h" +#include "object.h" +#include "commit.h" +#include "exec_cmd.h" +#include "diff.h" +#include "revision.h" +#include "list-objects.h" + +static const char upload_pack_usage[] = "git-upload-pack [--strict] [--timeout=nn] <dir>"; + +/* bits #0..7 in revision.h, #8..10 in commit.c */ +#define THEY_HAVE (1u << 11) +#define OUR_REF (1u << 12) +#define WANTED (1u << 13) +#define COMMON_KNOWN (1u << 14) +#define REACHABLE (1u << 15) + +#define SHALLOW (1u << 16) +#define NOT_SHALLOW (1u << 17) +#define CLIENT_SHALLOW (1u << 18) + +static unsigned long oldest_have; + +static int multi_ack, nr_our_refs; +static int use_thin_pack, use_ofs_delta, no_progress; +static struct object_array have_obj; +static struct object_array want_obj; +static unsigned int timeout; +/* 0 for no sideband, + * otherwise maximum packet size (up to 65520 bytes). + */ +static int use_sideband; + +static void reset_timeout(void) +{ + alarm(timeout); +} + +static int strip(char *line, int len) +{ + if (len && line[len-1] == '\n') + line[--len] = 0; + return len; +} + +static ssize_t send_client_data(int fd, const char *data, ssize_t sz) +{ + if (use_sideband) + return send_sideband(1, fd, data, sz, use_sideband); + if (fd == 3) + /* emergency quit */ + fd = 2; + if (fd == 2) { + /* XXX: are we happy to lose stuff here? */ + xwrite(fd, data, sz); + return sz; + } + return safe_write(fd, data, sz); +} + +FILE *pack_pipe = NULL; +static void show_commit(struct commit *commit) +{ + if (commit->object.flags & BOUNDARY) + fputc('-', pack_pipe); + if (fputs(sha1_to_hex(commit->object.sha1), pack_pipe) < 0) + die("broken output pipe"); + fputc('\n', pack_pipe); + fflush(pack_pipe); + free(commit->buffer); + commit->buffer = NULL; +} + +static void show_object(struct object_array_entry *p) +{ + /* An object with name "foo\n0000000..." can be used to + * confuse downstream git-pack-objects very badly. + */ + const char *ep = strchr(p->name, '\n'); + if (ep) { + fprintf(pack_pipe, "%s %.*s\n", sha1_to_hex(p->item->sha1), + (int) (ep - p->name), + p->name); + } + else + fprintf(pack_pipe, "%s %s\n", + sha1_to_hex(p->item->sha1), p->name); +} + +static void show_edge(struct commit *commit) +{ + fprintf(pack_pipe, "-%s\n", sha1_to_hex(commit->object.sha1)); +} + +static void create_pack_file(void) +{ + /* Pipes between rev-list to pack-objects, pack-objects to us + * and pack-objects error stream for progress bar. + */ + int lp_pipe[2], pu_pipe[2], pe_pipe[2]; + pid_t pid_rev_list, pid_pack_objects; + int create_full_pack = (nr_our_refs == want_obj.nr && !have_obj.nr); + char data[8193], progress[128]; + char abort_msg[] = "aborting due to possible repository " + "corruption on the remote side."; + int buffered = -1; + + if (pipe(lp_pipe) < 0) + die("git-upload-pack: unable to create pipe"); + pid_rev_list = fork(); + if (pid_rev_list < 0) + die("git-upload-pack: unable to fork git-rev-list"); + + if (!pid_rev_list) { + int i; + struct rev_info revs; + + close(lp_pipe[0]); + pack_pipe = fdopen(lp_pipe[1], "w"); + + if (create_full_pack) + use_thin_pack = 0; /* no point doing it */ + init_revisions(&revs, NULL); + revs.tag_objects = 1; + revs.tree_objects = 1; + revs.blob_objects = 1; + if (use_thin_pack) + revs.edge_hint = 1; + + if (create_full_pack) { + const char *args[] = {"rev-list", "--all", NULL}; + setup_revisions(2, args, &revs, NULL); + } else { + for (i = 0; i < want_obj.nr; i++) { + struct object *o = want_obj.objects[i].item; + /* why??? */ + o->flags &= ~UNINTERESTING; + add_pending_object(&revs, o, NULL); + } + for (i = 0; i < have_obj.nr; i++) { + struct object *o = have_obj.objects[i].item; + o->flags |= UNINTERESTING; + add_pending_object(&revs, o, NULL); + } + setup_revisions(0, NULL, &revs, NULL); + } + prepare_revision_walk(&revs); + mark_edges_uninteresting(revs.commits, &revs, show_edge); + traverse_commit_list(&revs, show_commit, show_object); + exit(0); + } + + if (pipe(pu_pipe) < 0) + die("git-upload-pack: unable to create pipe"); + if (pipe(pe_pipe) < 0) + die("git-upload-pack: unable to create pipe"); + pid_pack_objects = fork(); + if (pid_pack_objects < 0) { + /* daemon sets things up to ignore TERM */ + kill(pid_rev_list, SIGKILL); + die("git-upload-pack: unable to fork git-pack-objects"); + } + if (!pid_pack_objects) { + const char *argv[10]; + int i = 0; + + dup2(lp_pipe[0], 0); + dup2(pu_pipe[1], 1); + dup2(pe_pipe[1], 2); + + close(lp_pipe[0]); + close(lp_pipe[1]); + close(pu_pipe[0]); + close(pu_pipe[1]); + close(pe_pipe[0]); + close(pe_pipe[1]); + + argv[i++] = "pack-objects"; + argv[i++] = "--stdout"; + if (!no_progress) + argv[i++] = "--progress"; + if (use_ofs_delta) + argv[i++] = "--delta-base-offset"; + argv[i++] = NULL; + + execv_git_cmd(argv); + kill(pid_rev_list, SIGKILL); + die("git-upload-pack: unable to exec git-pack-objects"); + } + + close(lp_pipe[0]); + close(lp_pipe[1]); + + /* We read from pe_pipe[0] to capture stderr output for + * progress bar, and pu_pipe[0] to capture the pack data. + */ + close(pe_pipe[1]); + close(pu_pipe[1]); + + while (1) { + const char *who; + struct pollfd pfd[2]; + pid_t pid; + int status; + ssize_t sz; + int pe, pu, pollsize; + + reset_timeout(); + + pollsize = 0; + pe = pu = -1; + + if (0 <= pu_pipe[0]) { + pfd[pollsize].fd = pu_pipe[0]; + pfd[pollsize].events = POLLIN; + pu = pollsize; + pollsize++; + } + if (0 <= pe_pipe[0]) { + pfd[pollsize].fd = pe_pipe[0]; + pfd[pollsize].events = POLLIN; + pe = pollsize; + pollsize++; + } + + if (pollsize) { + if (poll(pfd, pollsize, -1) < 0) { + if (errno != EINTR) { + error("poll failed, resuming: %s", + strerror(errno)); + sleep(1); + } + continue; + } + if (0 <= pu && (pfd[pu].revents & (POLLIN|POLLHUP))) { + /* Data ready; we keep the last byte + * to ourselves in case we detect + * broken rev-list, so that we can + * leave the stream corrupted. This + * is unfortunate -- unpack-objects + * would happily accept a valid pack + * data with trailing garbage, so + * appending garbage after we pass all + * the pack data is not good enough to + * signal breakage to downstream. + */ + char *cp = data; + ssize_t outsz = 0; + if (0 <= buffered) { + *cp++ = buffered; + outsz++; + } + sz = xread(pu_pipe[0], cp, + sizeof(data) - outsz); + if (0 < sz) + ; + else if (sz == 0) { + close(pu_pipe[0]); + pu_pipe[0] = -1; + } + else + goto fail; + sz += outsz; + if (1 < sz) { + buffered = data[sz-1] & 0xFF; + sz--; + } + else + buffered = -1; + sz = send_client_data(1, data, sz); + if (sz < 0) + goto fail; + } + if (0 <= pe && (pfd[pe].revents & (POLLIN|POLLHUP))) { + /* Status ready; we ship that in the side-band + * or dump to the standard error. + */ + sz = xread(pe_pipe[0], progress, + sizeof(progress)); + if (0 < sz) + send_client_data(2, progress, sz); + else if (sz == 0) { + close(pe_pipe[0]); + pe_pipe[0] = -1; + } + else + goto fail; + } + } + + /* See if the children are still there */ + if (pid_rev_list || pid_pack_objects) { + pid = waitpid(-1, &status, WNOHANG); + if (!pid) + continue; + who = ((pid == pid_rev_list) ? "git-rev-list" : + (pid == pid_pack_objects) ? "git-pack-objects" : + NULL); + if (!who) { + if (pid < 0) { + error("git-upload-pack: %s", + strerror(errno)); + goto fail; + } + error("git-upload-pack: we weren't " + "waiting for %d", pid); + continue; + } + if (!WIFEXITED(status) || WEXITSTATUS(status) > 0) { + error("git-upload-pack: %s died with error.", + who); + goto fail; + } + if (pid == pid_rev_list) + pid_rev_list = 0; + if (pid == pid_pack_objects) + pid_pack_objects = 0; + if (pid_rev_list || pid_pack_objects) + continue; + } + + /* both died happily */ + if (pollsize) + continue; + + /* flush the data */ + if (0 <= buffered) { + data[0] = buffered; + sz = send_client_data(1, data, 1); + if (sz < 0) + goto fail; + fprintf(stderr, "flushed.\n"); + } + if (use_sideband) + packet_flush(1); + return; + } + fail: + if (pid_pack_objects) + kill(pid_pack_objects, SIGKILL); + if (pid_rev_list) + kill(pid_rev_list, SIGKILL); + send_client_data(3, abort_msg, sizeof(abort_msg)); + die("git-upload-pack: %s", abort_msg); +} + +static int got_sha1(char *hex, unsigned char *sha1) +{ + struct object *o; + int we_knew_they_have = 0; + + if (get_sha1_hex(hex, sha1)) + die("git-upload-pack: expected SHA1 object, got '%s'", hex); + if (!has_sha1_file(sha1)) + return -1; + + o = lookup_object(sha1); + if (!(o && o->parsed)) + o = parse_object(sha1); + if (!o) + die("oops (%s)", sha1_to_hex(sha1)); + if (o->type == OBJ_COMMIT) { + struct commit_list *parents; + struct commit *commit = (struct commit *)o; + if (o->flags & THEY_HAVE) + we_knew_they_have = 1; + else + o->flags |= THEY_HAVE; + if (!oldest_have || (commit->date < oldest_have)) + oldest_have = commit->date; + for (parents = commit->parents; + parents; + parents = parents->next) + parents->item->object.flags |= THEY_HAVE; + } + if (!we_knew_they_have) { + add_object_array(o, NULL, &have_obj); + return 1; + } + return 0; +} + +static int reachable(struct commit *want) +{ + struct commit_list *work = NULL; + + insert_by_date(want, &work); + while (work) { + struct commit_list *list = work->next; + struct commit *commit = work->item; + free(work); + work = list; + + if (commit->object.flags & THEY_HAVE) { + want->object.flags |= COMMON_KNOWN; + break; + } + if (!commit->object.parsed) + parse_object(commit->object.sha1); + if (commit->object.flags & REACHABLE) + continue; + commit->object.flags |= REACHABLE; + if (commit->date < oldest_have) + continue; + for (list = commit->parents; list; list = list->next) { + struct commit *parent = list->item; + if (!(parent->object.flags & REACHABLE)) + insert_by_date(parent, &work); + } + } + want->object.flags |= REACHABLE; + clear_commit_marks(want, REACHABLE); + free_commit_list(work); + return (want->object.flags & COMMON_KNOWN); +} + +static int ok_to_give_up(void) +{ + int i; + + if (!have_obj.nr) + return 0; + + for (i = 0; i < want_obj.nr; i++) { + struct object *want = want_obj.objects[i].item; + + if (want->flags & COMMON_KNOWN) + continue; + want = deref_tag(want, "a want line", 0); + if (!want || want->type != OBJ_COMMIT) { + /* no way to tell if this is reachable by + * looking at the ancestry chain alone, so + * leave a note to ourselves not to worry about + * this object anymore. + */ + want_obj.objects[i].item->flags |= COMMON_KNOWN; + continue; + } + if (!reachable((struct commit *)want)) + return 0; + } + return 1; +} + +static int get_common_commits(void) +{ + static char line[1000]; + unsigned char sha1[20]; + char hex[41], last_hex[41]; + int len; + + track_object_refs = 0; + save_commit_buffer = 0; + + for(;;) { + len = packet_read_line(0, line, sizeof(line)); + reset_timeout(); + + if (!len) { + if (have_obj.nr == 0 || multi_ack) + packet_write(1, "NAK\n"); + continue; + } + len = strip(line, len); + if (!prefixcmp(line, "have ")) { + switch (got_sha1(line+5, sha1)) { + case -1: /* they have what we do not */ + if (multi_ack && ok_to_give_up()) + packet_write(1, "ACK %s continue\n", + sha1_to_hex(sha1)); + break; + default: + memcpy(hex, sha1_to_hex(sha1), 41); + if (multi_ack) { + const char *msg = "ACK %s continue\n"; + packet_write(1, msg, hex); + memcpy(last_hex, hex, 41); + } + else if (have_obj.nr == 1) + packet_write(1, "ACK %s\n", hex); + break; + } + continue; + } + if (!strcmp(line, "done")) { + if (have_obj.nr > 0) { + if (multi_ack) + packet_write(1, "ACK %s\n", last_hex); + return 0; + } + packet_write(1, "NAK\n"); + return -1; + } + die("git-upload-pack: expected SHA1 list, got '%s'", line); + } +} + +static void receive_needs(void) +{ + struct object_array shallows = {0, 0, NULL}; + static char line[1000]; + int len, depth = 0; + + for (;;) { + struct object *o; + unsigned char sha1_buf[20]; + len = packet_read_line(0, line, sizeof(line)); + reset_timeout(); + if (!len) + break; + + if (!prefixcmp(line, "shallow ")) { + unsigned char sha1[20]; + struct object *object; + use_thin_pack = 0; + if (get_sha1(line + 8, sha1)) + die("invalid shallow line: %s", line); + object = parse_object(sha1); + if (!object) + die("did not find object for %s", line); + object->flags |= CLIENT_SHALLOW; + add_object_array(object, NULL, &shallows); + continue; + } + if (!prefixcmp(line, "deepen ")) { + char *end; + use_thin_pack = 0; + depth = strtol(line + 7, &end, 0); + if (end == line + 7 || depth <= 0) + die("Invalid deepen: %s", line); + continue; + } + if (prefixcmp(line, "want ") || + get_sha1_hex(line+5, sha1_buf)) + die("git-upload-pack: protocol error, " + "expected to get sha, not '%s'", line); + if (strstr(line+45, "multi_ack")) + multi_ack = 1; + if (strstr(line+45, "thin-pack")) + use_thin_pack = 1; + if (strstr(line+45, "ofs-delta")) + use_ofs_delta = 1; + if (strstr(line+45, "side-band-64k")) + use_sideband = LARGE_PACKET_MAX; + else if (strstr(line+45, "side-band")) + use_sideband = DEFAULT_PACKET_MAX; + if (strstr(line+45, "no-progress")) + no_progress = 1; + + /* We have sent all our refs already, and the other end + * should have chosen out of them; otherwise they are + * asking for nonsense. + * + * Hmph. We may later want to allow "want" line that + * asks for something like "master~10" (symbolic)... + * would it make sense? I don't know. + */ + o = lookup_object(sha1_buf); + if (!o || !(o->flags & OUR_REF)) + die("git-upload-pack: not our ref %s", line+5); + if (!(o->flags & WANTED)) { + o->flags |= WANTED; + add_object_array(o, NULL, &want_obj); + } + } + if (depth == 0 && shallows.nr == 0) + return; + if (depth > 0) { + struct commit_list *result, *backup; + int i; + backup = result = get_shallow_commits(&want_obj, depth, + SHALLOW, NOT_SHALLOW); + while (result) { + struct object *object = &result->item->object; + if (!(object->flags & (CLIENT_SHALLOW|NOT_SHALLOW))) { + packet_write(1, "shallow %s", + sha1_to_hex(object->sha1)); + register_shallow(object->sha1); + } + result = result->next; + } + free_commit_list(backup); + for (i = 0; i < shallows.nr; i++) { + struct object *object = shallows.objects[i].item; + if (object->flags & NOT_SHALLOW) { + struct commit_list *parents; + packet_write(1, "unshallow %s", + sha1_to_hex(object->sha1)); + object->flags &= ~CLIENT_SHALLOW; + /* make sure the real parents are parsed */ + unregister_shallow(object->sha1); + object->parsed = 0; + parse_commit((struct commit *)object); + parents = ((struct commit *)object)->parents; + while (parents) { + add_object_array(&parents->item->object, + NULL, &want_obj); + parents = parents->next; + } + } + /* make sure commit traversal conforms to client */ + register_shallow(object->sha1); + } + packet_flush(1); + } else + if (shallows.nr > 0) { + int i; + for (i = 0; i < shallows.nr; i++) + register_shallow(shallows.objects[i].item->sha1); + } + free(shallows.objects); +} + +static int send_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data) +{ + static const char *capabilities = "multi_ack thin-pack side-band" + " side-band-64k ofs-delta shallow no-progress"; + struct object *o = parse_object(sha1); + + if (!o) + die("git-upload-pack: cannot find object %s:", sha1_to_hex(sha1)); + + if (capabilities) + packet_write(1, "%s %s%c%s\n", sha1_to_hex(sha1), refname, + 0, capabilities); + else + packet_write(1, "%s %s\n", sha1_to_hex(sha1), refname); + capabilities = NULL; + if (!(o->flags & OUR_REF)) { + o->flags |= OUR_REF; + nr_our_refs++; + } + if (o->type == OBJ_TAG) { + o = deref_tag(o, refname, 0); + packet_write(1, "%s %s^{}\n", sha1_to_hex(o->sha1), refname); + } + return 0; +} + +static void upload_pack(void) +{ + reset_timeout(); + head_ref(send_ref, NULL); + for_each_ref(send_ref, NULL); + packet_flush(1); + receive_needs(); + if (want_obj.nr) { + get_common_commits(); + create_pack_file(); + } +} + +int main(int argc, char **argv) +{ + char *dir; + int i; + int strict = 0; + + for (i = 1; i < argc; i++) { + char *arg = argv[i]; + + if (arg[0] != '-') + break; + if (!strcmp(arg, "--strict")) { + strict = 1; + continue; + } + if (!prefixcmp(arg, "--timeout=")) { + timeout = atoi(arg+10); + continue; + } + if (!strcmp(arg, "--")) { + i++; + break; + } + } + + if (i != argc-1) + usage(upload_pack_usage); + dir = argv[i]; + + if (!enter_repo(dir, strict)) + die("'%s': unable to chdir or not a git archive", dir); + if (is_repository_shallow()) + die("attempt to fetch/clone from a shallow repository"); + upload_pack(); + return 0; +} |