diff options
Diffstat (limited to 'upload-pack.c')
| -rw-r--r-- | upload-pack.c | 875 |
1 files changed, 875 insertions, 0 deletions
diff --git a/upload-pack.c b/upload-pack.c new file mode 100644 index 0000000000..89e832b64a --- /dev/null +++ b/upload-pack.c @@ -0,0 +1,875 @@ +#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" +#include "run-command.h" +#include "connect.h" +#include "sigchain.h" +#include "version.h" +#include "string-list.h" + +static const char upload_pack_usage[] = "git upload-pack [--strict] [--timeout=<n>] <dir>"; + +/* Remember to update object flag allocation in object.h */ +#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) +#define HIDDEN_REF (1u << 19) + +static unsigned long oldest_have; + +static int multi_ack; +static int no_done; +static int use_thin_pack, use_ofs_delta, use_include_tag; +static int no_progress, daemon_mode; +/* Allow specifying sha1 if it is a ref tip. */ +#define ALLOW_TIP_SHA1 01 +/* Allow request of a sha1 if it is reachable from a ref (possibly hidden ref). */ +#define ALLOW_REACHABLE_SHA1 02 +static unsigned int allow_unadvertised_object_request; +static int shallow_nr; +static struct object_array have_obj; +static struct object_array want_obj; +static struct object_array extra_edge_obj; +static unsigned int timeout; +static int keepalive = 5; +/* 0 for no sideband, + * otherwise maximum packet size (up to 65520 bytes). + */ +static int use_sideband; +static int advertise_refs; +static int stateless_rpc; + +static void reset_timeout(void) +{ + alarm(timeout); +} + +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; + } + write_or_die(fd, data, sz); + return sz; +} + +static int write_one_shallow(const struct commit_graft *graft, void *cb_data) +{ + FILE *fp = cb_data; + if (graft->nr_parent == -1) + fprintf(fp, "--shallow %s\n", oid_to_hex(&graft->oid)); + return 0; +} + +static void create_pack_file(void) +{ + struct child_process pack_objects = CHILD_PROCESS_INIT; + char data[8193], progress[128]; + char abort_msg[] = "aborting due to possible repository " + "corruption on the remote side."; + int buffered = -1; + ssize_t sz; + const char *argv[13]; + int i, arg = 0; + FILE *pipe_fd; + + if (shallow_nr) { + argv[arg++] = "--shallow-file"; + argv[arg++] = ""; + } + argv[arg++] = "pack-objects"; + argv[arg++] = "--revs"; + if (use_thin_pack) + argv[arg++] = "--thin"; + + argv[arg++] = "--stdout"; + if (shallow_nr) + argv[arg++] = "--shallow"; + if (!no_progress) + argv[arg++] = "--progress"; + if (use_ofs_delta) + argv[arg++] = "--delta-base-offset"; + if (use_include_tag) + argv[arg++] = "--include-tag"; + argv[arg++] = NULL; + + pack_objects.in = -1; + pack_objects.out = -1; + pack_objects.err = -1; + pack_objects.git_cmd = 1; + pack_objects.argv = argv; + + if (start_command(&pack_objects)) + die("git upload-pack: unable to fork git-pack-objects"); + + pipe_fd = xfdopen(pack_objects.in, "w"); + + if (shallow_nr) + for_each_commit_graft(write_one_shallow, pipe_fd); + + for (i = 0; i < want_obj.nr; i++) + fprintf(pipe_fd, "%s\n", + sha1_to_hex(want_obj.objects[i].item->sha1)); + fprintf(pipe_fd, "--not\n"); + for (i = 0; i < have_obj.nr; i++) + fprintf(pipe_fd, "%s\n", + sha1_to_hex(have_obj.objects[i].item->sha1)); + for (i = 0; i < extra_edge_obj.nr; i++) + fprintf(pipe_fd, "%s\n", + sha1_to_hex(extra_edge_obj.objects[i].item->sha1)); + fprintf(pipe_fd, "\n"); + fflush(pipe_fd); + fclose(pipe_fd); + + /* We read from pack_objects.err to capture stderr output for + * progress bar, and pack_objects.out to capture the pack data. + */ + + while (1) { + struct pollfd pfd[2]; + int pe, pu, pollsize; + int ret; + + reset_timeout(); + + pollsize = 0; + pe = pu = -1; + + if (0 <= pack_objects.out) { + pfd[pollsize].fd = pack_objects.out; + pfd[pollsize].events = POLLIN; + pu = pollsize; + pollsize++; + } + if (0 <= pack_objects.err) { + pfd[pollsize].fd = pack_objects.err; + pfd[pollsize].events = POLLIN; + pe = pollsize; + pollsize++; + } + + if (!pollsize) + break; + + ret = poll(pfd, pollsize, + keepalive < 0 ? -1 : 1000 * keepalive); + + if (ret < 0) { + if (errno != EINTR) { + error("poll failed, resuming: %s", + strerror(errno)); + sleep(1); + } + continue; + } + 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(pack_objects.err, progress, + sizeof(progress)); + if (0 < sz) + send_client_data(2, progress, sz); + else if (sz == 0) { + close(pack_objects.err); + pack_objects.err = -1; + } + else + goto fail; + /* give priority to status messages */ + 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 packdata 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(pack_objects.out, cp, + sizeof(data) - outsz); + if (0 < sz) + ; + else if (sz == 0) { + close(pack_objects.out); + pack_objects.out = -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; + } + + /* + * We hit the keepalive timeout without saying anything; send + * an empty message on the data sideband just to let the other + * side know we're still working on it, but don't have any data + * yet. + * + * If we don't have a sideband channel, there's no room in the + * protocol to say anything, so those clients are just out of + * luck. + */ + if (!ret && use_sideband) { + static const char buf[] = "0005\1"; + write_or_die(1, buf, 5); + } + } + + if (finish_command(&pack_objects)) { + error("git upload-pack: git-pack-objects died with error."); + goto fail; + } + + /* 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: + 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 = 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; + + commit_list_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)) + commit_list_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) +{ + unsigned char sha1[20]; + char last_hex[41]; + int got_common = 0; + int got_other = 0; + int sent_ready = 0; + + save_commit_buffer = 0; + + for (;;) { + char *line = packet_read_line(0, NULL); + reset_timeout(); + + if (!line) { + if (multi_ack == 2 && got_common + && !got_other && ok_to_give_up()) { + sent_ready = 1; + packet_write(1, "ACK %s ready\n", last_hex); + } + if (have_obj.nr == 0 || multi_ack) + packet_write(1, "NAK\n"); + + if (no_done && sent_ready) { + packet_write(1, "ACK %s\n", last_hex); + return 0; + } + if (stateless_rpc) + exit(0); + got_common = 0; + got_other = 0; + continue; + } + if (starts_with(line, "have ")) { + switch (got_sha1(line+5, sha1)) { + case -1: /* they have what we do not */ + got_other = 1; + if (multi_ack && ok_to_give_up()) { + const char *hex = sha1_to_hex(sha1); + if (multi_ack == 2) { + sent_ready = 1; + packet_write(1, "ACK %s ready\n", hex); + } else + packet_write(1, "ACK %s continue\n", hex); + } + break; + default: + got_common = 1; + memcpy(last_hex, sha1_to_hex(sha1), 41); + if (multi_ack == 2) + packet_write(1, "ACK %s common\n", last_hex); + else if (multi_ack) + packet_write(1, "ACK %s continue\n", last_hex); + else if (have_obj.nr == 1) + packet_write(1, "ACK %s\n", last_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 int is_our_ref(struct object *o) +{ + int allow_hidden_ref = (allow_unadvertised_object_request & + (ALLOW_TIP_SHA1 | ALLOW_REACHABLE_SHA1)); + return o->flags & ((allow_hidden_ref ? HIDDEN_REF : 0) | OUR_REF); +} + +static void check_non_tip(void) +{ + static const char *argv[] = { + "rev-list", "--stdin", NULL, + }; + static struct child_process cmd = CHILD_PROCESS_INIT; + struct object *o; + char namebuf[42]; /* ^ + SHA-1 + LF */ + int i; + + /* + * In the normal in-process case without + * uploadpack.allowReachableSHA1InWant, + * non-tip requests can never happen. + */ + if (!stateless_rpc && !(allow_unadvertised_object_request & ALLOW_REACHABLE_SHA1)) + goto error; + + cmd.argv = argv; + cmd.git_cmd = 1; + cmd.no_stderr = 1; + cmd.in = -1; + cmd.out = -1; + + if (start_command(&cmd)) + goto error; + + /* + * If rev-list --stdin encounters an unknown commit, it + * terminates, which will cause SIGPIPE in the write loop + * below. + */ + sigchain_push(SIGPIPE, SIG_IGN); + + namebuf[0] = '^'; + namebuf[41] = '\n'; + for (i = get_max_object_index(); 0 < i; ) { + o = get_indexed_object(--i); + if (!o) + continue; + if (!is_our_ref(o)) + continue; + memcpy(namebuf + 1, sha1_to_hex(o->sha1), 40); + if (write_in_full(cmd.in, namebuf, 42) < 0) + goto error; + } + namebuf[40] = '\n'; + for (i = 0; i < want_obj.nr; i++) { + o = want_obj.objects[i].item; + if (is_our_ref(o)) + continue; + memcpy(namebuf, sha1_to_hex(o->sha1), 40); + if (write_in_full(cmd.in, namebuf, 41) < 0) + goto error; + } + close(cmd.in); + + sigchain_pop(SIGPIPE); + + /* + * The commits out of the rev-list are not ancestors of + * our ref. + */ + i = read_in_full(cmd.out, namebuf, 1); + if (i) + goto error; + close(cmd.out); + + /* + * rev-list may have died by encountering a bad commit + * in the history, in which case we do want to bail out + * even when it showed no commit. + */ + if (finish_command(&cmd)) + goto error; + + /* All the non-tip ones are ancestors of what we advertised */ + return; + +error: + /* Pick one of them (we know there at least is one) */ + for (i = 0; i < want_obj.nr; i++) { + o = want_obj.objects[i].item; + if (!is_our_ref(o)) + die("git upload-pack: not our ref %s", + sha1_to_hex(o->sha1)); + } +} + +static void receive_needs(void) +{ + struct object_array shallows = OBJECT_ARRAY_INIT; + int depth = 0; + int has_non_tip = 0; + + shallow_nr = 0; + for (;;) { + struct object *o; + const char *features; + unsigned char sha1_buf[20]; + char *line = packet_read_line(0, NULL); + reset_timeout(); + if (!line) + break; + + if (starts_with(line, "shallow ")) { + unsigned char sha1[20]; + struct object *object; + if (get_sha1_hex(line + 8, sha1)) + die("invalid shallow line: %s", line); + object = parse_object(sha1); + if (!object) + continue; + if (object->type != OBJ_COMMIT) + die("invalid shallow object %s", sha1_to_hex(sha1)); + if (!(object->flags & CLIENT_SHALLOW)) { + object->flags |= CLIENT_SHALLOW; + add_object_array(object, NULL, &shallows); + } + continue; + } + if (starts_with(line, "deepen ")) { + char *end; + depth = strtol(line + 7, &end, 0); + if (end == line + 7 || depth <= 0) + die("Invalid deepen: %s", line); + continue; + } + if (!starts_with(line, "want ") || + get_sha1_hex(line+5, sha1_buf)) + die("git upload-pack: protocol error, " + "expected to get sha, not '%s'", line); + + features = line + 45; + + if (parse_feature_request(features, "multi_ack_detailed")) + multi_ack = 2; + else if (parse_feature_request(features, "multi_ack")) + multi_ack = 1; + if (parse_feature_request(features, "no-done")) + no_done = 1; + if (parse_feature_request(features, "thin-pack")) + use_thin_pack = 1; + if (parse_feature_request(features, "ofs-delta")) + use_ofs_delta = 1; + if (parse_feature_request(features, "side-band-64k")) + use_sideband = LARGE_PACKET_MAX; + else if (parse_feature_request(features, "side-band")) + use_sideband = DEFAULT_PACKET_MAX; + if (parse_feature_request(features, "no-progress")) + no_progress = 1; + if (parse_feature_request(features, "include-tag")) + use_include_tag = 1; + + o = parse_object(sha1_buf); + if (!o) + die("git upload-pack: not our ref %s", + sha1_to_hex(sha1_buf)); + if (!(o->flags & WANTED)) { + o->flags |= WANTED; + if (!is_our_ref(o)) + has_non_tip = 1; + add_object_array(o, NULL, &want_obj); + } + } + + /* + * We have sent all our refs already, and the other end + * should have chosen out of them. When we are operating + * in the stateless RPC mode, however, their choice may + * have been based on the set of older refs advertised + * by another process that handled the initial request. + */ + if (has_non_tip) + check_non_tip(); + + if (!use_sideband && daemon_mode) + no_progress = 1; + + if (depth == 0 && shallows.nr == 0) + return; + if (depth > 0) { + struct commit_list *result = NULL, *backup = NULL; + int i; + if (depth == INFINITE_DEPTH && !is_repository_shallow()) + for (i = 0; i < shallows.nr; i++) { + struct object *object = shallows.objects[i].item; + object->flags |= NOT_SHALLOW; + } + else + 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); + shallow_nr++; + } + 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_or_die((struct commit *)object); + parents = ((struct commit *)object)->parents; + while (parents) { + add_object_array(&parents->item->object, + NULL, &want_obj); + parents = parents->next; + } + add_object_array(object, NULL, &extra_edge_obj); + } + /* 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); + } + + shallow_nr += shallows.nr; + free(shallows.objects); +} + +/* return non-zero if the ref is hidden, otherwise 0 */ +static int mark_our_ref(const char *refname, const struct object_id *oid) +{ + struct object *o = lookup_unknown_object(oid->hash); + + if (ref_is_hidden(refname)) { + o->flags |= HIDDEN_REF; + return 1; + } + o->flags |= OUR_REF; + return 0; +} + +static int check_ref(const char *refname, const struct object_id *oid, + int flag, void *cb_data) +{ + mark_our_ref(refname, oid); + return 0; +} + +static void format_symref_info(struct strbuf *buf, struct string_list *symref) +{ + struct string_list_item *item; + + if (!symref->nr) + return; + for_each_string_list_item(item, symref) + strbuf_addf(buf, " symref=%s:%s", item->string, (char *)item->util); +} + +static int send_ref(const char *refname, const struct object_id *oid, + int flag, void *cb_data) +{ + static const char *capabilities = "multi_ack thin-pack side-band" + " side-band-64k ofs-delta shallow no-progress" + " include-tag multi_ack_detailed"; + const char *refname_nons = strip_namespace(refname); + struct object_id peeled; + + if (mark_our_ref(refname, oid)) + return 0; + + if (capabilities) { + struct strbuf symref_info = STRBUF_INIT; + + format_symref_info(&symref_info, cb_data); + packet_write(1, "%s %s%c%s%s%s%s%s agent=%s\n", + oid_to_hex(oid), refname_nons, + 0, capabilities, + (allow_unadvertised_object_request & ALLOW_TIP_SHA1) ? + " allow-tip-sha1-in-want" : "", + (allow_unadvertised_object_request & ALLOW_REACHABLE_SHA1) ? + " allow-reachable-sha1-in-want" : "", + stateless_rpc ? " no-done" : "", + symref_info.buf, + git_user_agent_sanitized()); + strbuf_release(&symref_info); + } else { + packet_write(1, "%s %s\n", oid_to_hex(oid), refname_nons); + } + capabilities = NULL; + if (!peel_ref(refname, peeled.hash)) + packet_write(1, "%s %s^{}\n", oid_to_hex(&peeled), refname_nons); + return 0; +} + +static int find_symref(const char *refname, const struct object_id *oid, + int flag, void *cb_data) +{ + const char *symref_target; + struct string_list_item *item; + struct object_id unused; + + if ((flag & REF_ISSYMREF) == 0) + return 0; + symref_target = resolve_ref_unsafe(refname, 0, unused.hash, &flag); + if (!symref_target || (flag & REF_ISSYMREF) == 0) + die("'%s' is a symref but it is not?", refname); + item = string_list_append(cb_data, refname); + item->util = xstrdup(symref_target); + return 0; +} + +static void upload_pack(void) +{ + struct string_list symref = STRING_LIST_INIT_DUP; + + head_ref_namespaced(find_symref, &symref); + + if (advertise_refs || !stateless_rpc) { + reset_timeout(); + head_ref_namespaced(send_ref, &symref); + for_each_namespaced_ref(send_ref, &symref); + advertise_shallow_grafts(1); + packet_flush(1); + } else { + head_ref_namespaced(check_ref, NULL); + for_each_namespaced_ref(check_ref, NULL); + } + string_list_clear(&symref, 1); + if (advertise_refs) + return; + + receive_needs(); + if (want_obj.nr) { + get_common_commits(); + create_pack_file(); + } +} + +static int upload_pack_config(const char *var, const char *value, void *unused) +{ + if (!strcmp("uploadpack.allowtipsha1inwant", var)) { + if (git_config_bool(var, value)) + allow_unadvertised_object_request |= ALLOW_TIP_SHA1; + else + allow_unadvertised_object_request &= ~ALLOW_TIP_SHA1; + } else if (!strcmp("uploadpack.allowreachablesha1inwant", var)) { + if (git_config_bool(var, value)) + allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1; + else + allow_unadvertised_object_request &= ~ALLOW_REACHABLE_SHA1; + } else if (!strcmp("uploadpack.keepalive", var)) { + keepalive = git_config_int(var, value); + if (!keepalive) + keepalive = -1; + } + return parse_hide_refs_config(var, value, "uploadpack"); +} + +int main(int argc, char **argv) +{ + char *dir; + int i; + int strict = 0; + + git_setup_gettext(); + + packet_trace_identity("upload-pack"); + git_extract_argv0_path(argv[0]); + check_replace_refs = 0; + + for (i = 1; i < argc; i++) { + char *arg = argv[i]; + + if (arg[0] != '-') + break; + if (!strcmp(arg, "--advertise-refs")) { + advertise_refs = 1; + continue; + } + if (!strcmp(arg, "--stateless-rpc")) { + stateless_rpc = 1; + continue; + } + if (!strcmp(arg, "--strict")) { + strict = 1; + continue; + } + if (starts_with(arg, "--timeout=")) { + timeout = atoi(arg+10); + daemon_mode = 1; + continue; + } + if (!strcmp(arg, "--")) { + i++; + break; + } + } + + if (i != argc-1) + usage(upload_pack_usage); + + setup_path(); + + dir = argv[i]; + + if (!enter_repo(dir, strict)) + die("'%s' does not appear to be a git repository", dir); + + git_config(upload_pack_config, NULL); + upload_pack(); + return 0; +} |