diff options
Diffstat (limited to 'builtin-fetch-pack.c')
-rw-r--r-- | builtin-fetch-pack.c | 828 |
1 files changed, 828 insertions, 0 deletions
diff --git a/builtin-fetch-pack.c b/builtin-fetch-pack.c new file mode 100644 index 000000000..372bfa20a --- /dev/null +++ b/builtin-fetch-pack.c @@ -0,0 +1,828 @@ +#include "cache.h" +#include "refs.h" +#include "pkt-line.h" +#include "commit.h" +#include "tag.h" +#include "exec_cmd.h" +#include "pack.h" +#include "sideband.h" +#include "fetch-pack.h" +#include "remote.h" +#include "run-command.h" + +static int transfer_unpack_limit = -1; +static int fetch_unpack_limit = -1; +static int unpack_limit = 100; +static struct fetch_pack_args args = { + /* .uploadpack = */ "git-upload-pack", +}; + +static const char fetch_pack_usage[] = +"git fetch-pack [--all] [--quiet|-q] [--keep|-k] [--thin] [--include-tag] [--upload-pack=<git-upload-pack>] [--depth=<n>] [--no-progress] [-v] [<host>:]<directory> [<refs>...]"; + +#define COMPLETE (1U << 0) +#define COMMON (1U << 1) +#define COMMON_REF (1U << 2) +#define SEEN (1U << 3) +#define POPPED (1U << 4) + +static int marked; + +/* + * After sending this many "have"s if we do not get any new ACK , we + * give up traversing our history. + */ +#define MAX_IN_VAIN 256 + +static struct commit_list *rev_list; +static int non_common_revs, multi_ack, use_sideband; + +static void rev_list_push(struct commit *commit, int mark) +{ + if (!(commit->object.flags & mark)) { + commit->object.flags |= mark; + + if (!(commit->object.parsed)) + if (parse_commit(commit)) + return; + + 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, int flag, void *cb_data) +{ + struct object *o = deref_tag(parse_object(sha1), path, 0); + + if (o && o->type == OBJ_COMMIT) + rev_list_push((struct commit *)o, SEEN); + + return 0; +} + +static int clear_marks(const char *path, const unsigned char *sha1, int flag, void *cb_data) +{ + struct object *o = deref_tag(parse_object(sha1), path, 0); + + if (o && o->type == OBJ_COMMIT) + clear_commit_marks((struct commit *)o, + COMMON | COMMON_REF | SEEN | POPPED); + 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) + if (parse_commit(commit)) + return; + + 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); + parents = commit->parents; + + commit->object.flags |= POPPED; + if (!(commit->object.flags & COMMON)) + non_common_revs--; + + 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; + unsigned in_vain = 0; + int got_continue = 0; + + if (marked) + for_each_ref(clear_marks, NULL); + marked = 1; + + for_each_ref(rev_list_insert_ref, NULL); + + 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; + } + + if (!fetching) + packet_write(fd[1], "want %s%s%s%s%s%s%s%s\n", + sha1_to_hex(remote), + (multi_ack ? " multi_ack" : ""), + (use_sideband == 2 ? " side-band-64k" : ""), + (use_sideband == 1 ? " side-band" : ""), + (args.use_thin_pack ? " thin-pack" : ""), + (args.no_progress ? " no-progress" : ""), + (args.include_tag ? " include-tag" : ""), + " ofs-delta"); + else + packet_write(fd[1], "want %s\n", sha1_to_hex(remote)); + fetching++; + } + if (is_repository_shallow()) + write_shallow_commits(fd[1], 1); + if (args.depth > 0) + packet_write(fd[1], "deepen %d", args.depth); + packet_flush(fd[1]); + if (!fetching) + return 1; + + if (args.depth > 0) { + char line[1024]; + unsigned char sha1[20]; + int len; + + while ((len = packet_read_line(fd[0], line, sizeof(line)))) { + if (!prefixcmp(line, "shallow ")) { + if (get_sha1_hex(line + 8, sha1)) + die("invalid shallow line: %s", line); + register_shallow(sha1); + continue; + } + if (!prefixcmp(line, "unshallow ")) { + if (get_sha1_hex(line + 10, sha1)) + die("invalid unshallow line: %s", line); + if (!lookup_object(sha1)) + die("object not found: %s", line); + /* make sure that it is parsed as shallow */ + if (!parse_object(sha1)) + die("error in object: %s", line); + if (unregister_shallow(sha1)) + die("no shallow found: %s", line); + continue; + } + die("expected shallow/unshallow, got %s", line); + } + } + + flushes = 0; + retval = -1; + while ((sha1 = get_rev())) { + packet_write(fd[1], "have %s\n", sha1_to_hex(sha1)); + if (args.verbose) + fprintf(stderr, "have %s\n", sha1_to_hex(sha1)); + in_vain++; + 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 (args.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; + in_vain = 0; + got_continue = 1; + } + } while (ack); + flushes--; + if (got_continue && MAX_IN_VAIN < in_vain) { + if (args.verbose) + fprintf(stderr, "giving up\n"); + break; /* give up */ + } + } + } +done: + packet_write(fd[1], "done\n"); + if (args.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 (args.verbose) + fprintf(stderr, "got ack (%d) %s\n", ack, + sha1_to_hex(result_sha1)); + if (ack == 1) + return 0; + multi_ack = 1; + continue; + } + flushes--; + } + /* it is no error to fetch into a completely empty repo */ + return count ? retval : 0; +} + +static struct commit_list *complete; + +static int mark_complete(const char *path, const unsigned char *sha1, int flag, void *cb_data) +{ + struct object *o = parse_object(sha1); + + while (o && o->type == OBJ_TAG) { + 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 == OBJ_COMMIT) { + 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 (args.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 **return_refs; + struct ref *newlist = NULL; + struct ref **newtail = &newlist; + struct ref *ref, *next; + struct ref *fastarray[32]; + + if (nr_match && !args.fetch_all) { + if (ARRAY_SIZE(fastarray) < nr_match) + return_refs = xcalloc(nr_match, sizeof(struct ref *)); + else { + return_refs = fastarray; + memset(return_refs, 0, sizeof(struct ref *) * nr_match); + } + } + else + return_refs = NULL; + + for (ref = *refs; ref; ref = next) { + next = ref->next; + if (!memcmp(ref->name, "refs/", 5) && + check_ref_format(ref->name + 5)) + ; /* trash */ + else if (args.fetch_all && + (!args.depth || prefixcmp(ref->name, "refs/tags/") )) { + *newtail = ref; + ref->next = NULL; + newtail = &ref->next; + continue; + } + else { + int order = path_match(ref->name, nr_match, match); + if (order) { + return_refs[order-1] = ref; + continue; /* we will link it later */ + } + } + free(ref); + } + + if (!args.fetch_all) { + int i; + for (i = 0; i < nr_match; i++) { + ref = return_refs[i]; + if (ref) { + *newtail = ref; + ref->next = NULL; + newtail = &ref->next; + } + } + if (return_refs != fastarray) + free(return_refs); + } + *refs = newlist; +} + +static int everything_local(struct ref **refs, int nr_match, char **match) +{ + struct ref *ref; + int retval; + unsigned long cutoff = 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 == OBJ_COMMIT) { + struct commit *commit = (struct commit *)o; + if (!cutoff || cutoff < commit->date) + cutoff = commit->date; + } + } + + if (!args.depth) { + for_each_ref(mark_complete, NULL); + 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 != OBJ_COMMIT || !(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 (!args.verbose) + continue; + fprintf(stderr, + "want %s (%s)\n", sha1_to_hex(remote), + ref->name); + continue; + } + + hashcpy(ref->new_sha1, local); + if (!args.verbose) + continue; + fprintf(stderr, + "already have %s (%s)\n", sha1_to_hex(remote), + ref->name); + } + return retval; +} + +static int sideband_demux(int fd, void *data) +{ + int *xd = data; + + return recv_sideband("fetch-pack", xd[0], fd, 2); +} + +static int get_pack(int xd[2], char **pack_lockfile) +{ + struct async demux; + const char *argv[20]; + char keep_arg[256]; + char hdr_arg[256]; + const char **av; + int do_keep = args.keep_pack; + struct child_process cmd; + + memset(&demux, 0, sizeof(demux)); + if (use_sideband) { + /* xd[] is talking with upload-pack; subprocess reads from + * xd[0], spits out band#2 to stderr, and feeds us band#1 + * through demux->out. + */ + demux.proc = sideband_demux; + demux.data = xd; + if (start_async(&demux)) + die("fetch-pack: unable to fork off sideband" + " demultiplexer"); + } + else + demux.out = xd[0]; + + memset(&cmd, 0, sizeof(cmd)); + cmd.argv = argv; + av = argv; + *hdr_arg = 0; + if (!args.keep_pack && unpack_limit) { + struct pack_header header; + + if (read_pack_header(demux.out, &header)) + die("protocol error: bad pack header"); + snprintf(hdr_arg, sizeof(hdr_arg), + "--pack_header=%"PRIu32",%"PRIu32, + ntohl(header.hdr_version), ntohl(header.hdr_entries)); + if (ntohl(header.hdr_entries) < unpack_limit) + do_keep = 0; + else + do_keep = 1; + } + + if (do_keep) { + if (pack_lockfile) + cmd.out = -1; + *av++ = "index-pack"; + *av++ = "--stdin"; + if (!args.quiet && !args.no_progress) + *av++ = "-v"; + if (args.use_thin_pack) + *av++ = "--fix-thin"; + if (args.lock_pack || unpack_limit) { + int s = sprintf(keep_arg, + "--keep=fetch-pack %"PRIuMAX " on ", (uintmax_t) getpid()); + if (gethostname(keep_arg + s, sizeof(keep_arg) - s)) + strcpy(keep_arg + s, "localhost"); + *av++ = keep_arg; + } + } + else { + *av++ = "unpack-objects"; + if (args.quiet) + *av++ = "-q"; + } + if (*hdr_arg) + *av++ = hdr_arg; + *av++ = NULL; + + cmd.in = demux.out; + cmd.git_cmd = 1; + if (start_command(&cmd)) + die("fetch-pack: unable to fork off %s", argv[0]); + if (do_keep && pack_lockfile) { + *pack_lockfile = index_pack_lockfile(cmd.out); + close(cmd.out); + } + + if (finish_command(&cmd)) + die("%s failed", argv[0]); + if (use_sideband && finish_async(&demux)) + die("error in sideband demultiplexer"); + return 0; +} + +static struct ref *do_fetch_pack(int fd[2], + const struct ref *orig_ref, + int nr_match, + char **match, + char **pack_lockfile) +{ + struct ref *ref = copy_ref_list(orig_ref); + unsigned char sha1[20]; + + if (is_repository_shallow() && !server_supports("shallow")) + die("Server does not support shallow clients"); + if (server_supports("multi_ack")) { + if (args.verbose) + fprintf(stderr, "Server supports multi_ack\n"); + multi_ack = 1; + } + if (server_supports("side-band-64k")) { + if (args.verbose) + fprintf(stderr, "Server supports side-band-64k\n"); + use_sideband = 2; + } + else if (server_supports("side-band")) { + if (args.verbose) + fprintf(stderr, "Server supports side-band\n"); + use_sideband = 1; + } + if (everything_local(&ref, nr_match, match)) { + packet_flush(fd[1]); + goto all_done; + } + if (find_common(fd, sha1, ref) < 0) + if (!args.keep_pack) + /* When cloning, it is not unusual to have + * no common commit. + */ + fprintf(stderr, "warning: no common commits\n"); + + if (get_pack(fd, pack_lockfile)) + die("git fetch-pack: fetch failed."); + + all_done: + return ref; +} + +static int remove_duplicates(int nr_heads, char **heads) +{ + int src, dst; + + for (src = dst = 0; src < nr_heads; src++) { + /* If heads[src] is different from any of + * heads[0..dst], push it in. + */ + int i; + for (i = 0; i < dst; i++) { + if (!strcmp(heads[i], heads[src])) + break; + } + if (i < dst) + continue; + if (src != dst) + heads[dst] = heads[src]; + dst++; + } + return dst; +} + +static int fetch_pack_config(const char *var, const char *value, void *cb) +{ + if (strcmp(var, "fetch.unpacklimit") == 0) { + fetch_unpack_limit = git_config_int(var, value); + return 0; + } + + if (strcmp(var, "transfer.unpacklimit") == 0) { + transfer_unpack_limit = git_config_int(var, value); + return 0; + } + + return git_default_config(var, value, cb); +} + +static struct lock_file lock; + +static void fetch_pack_setup(void) +{ + static int did_setup; + if (did_setup) + return; + git_config(fetch_pack_config, NULL); + if (0 <= transfer_unpack_limit) + unpack_limit = transfer_unpack_limit; + else if (0 <= fetch_unpack_limit) + unpack_limit = fetch_unpack_limit; + did_setup = 1; +} + +int cmd_fetch_pack(int argc, const char **argv, const char *prefix) +{ + int i, ret, nr_heads; + struct ref *ref = NULL; + char *dest = NULL, **heads; + int fd[2]; + struct child_process *conn; + + nr_heads = 0; + heads = NULL; + for (i = 1; i < argc; i++) { + const char *arg = argv[i]; + + if (*arg == '-') { + if (!prefixcmp(arg, "--upload-pack=")) { + args.uploadpack = arg + 14; + continue; + } + if (!prefixcmp(arg, "--exec=")) { + args.uploadpack = arg + 7; + continue; + } + if (!strcmp("--quiet", arg) || !strcmp("-q", arg)) { + args.quiet = 1; + continue; + } + if (!strcmp("--keep", arg) || !strcmp("-k", arg)) { + args.lock_pack = args.keep_pack; + args.keep_pack = 1; + continue; + } + if (!strcmp("--thin", arg)) { + args.use_thin_pack = 1; + continue; + } + if (!strcmp("--include-tag", arg)) { + args.include_tag = 1; + continue; + } + if (!strcmp("--all", arg)) { + args.fetch_all = 1; + continue; + } + if (!strcmp("-v", arg)) { + args.verbose = 1; + continue; + } + if (!prefixcmp(arg, "--depth=")) { + args.depth = strtol(arg + 8, NULL, 0); + continue; + } + if (!strcmp("--no-progress", arg)) { + args.no_progress = 1; + continue; + } + usage(fetch_pack_usage); + } + dest = (char *)arg; + heads = (char **)(argv + i + 1); + nr_heads = argc - i - 1; + break; + } + if (!dest) + usage(fetch_pack_usage); + + conn = git_connect(fd, (char *)dest, args.uploadpack, + args.verbose ? CONNECT_VERBOSE : 0); + if (conn) { + get_remote_heads(fd[0], &ref, 0, NULL, 0, NULL); + + ref = fetch_pack(&args, fd, conn, ref, dest, nr_heads, heads, NULL); + close(fd[0]); + close(fd[1]); + if (finish_connect(conn)) + ref = NULL; + } else { + ref = NULL; + } + ret = !ref; + + 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; + } + } + while (ref) { + printf("%s %s\n", + sha1_to_hex(ref->old_sha1), ref->name); + ref = ref->next; + } + + return ret; +} + +struct ref *fetch_pack(struct fetch_pack_args *my_args, + int fd[], struct child_process *conn, + const struct ref *ref, + const char *dest, + int nr_heads, + char **heads, + char **pack_lockfile) +{ + struct stat st; + struct ref *ref_cpy; + + fetch_pack_setup(); + memcpy(&args, my_args, sizeof(args)); + if (args.depth > 0) { + if (stat(git_path("shallow"), &st)) + st.st_mtime = 0; + } + + if (heads && nr_heads) + nr_heads = remove_duplicates(nr_heads, heads); + if (!ref) { + packet_flush(fd[1]); + die("no matching remote head"); + } + ref_cpy = do_fetch_pack(fd, ref, nr_heads, heads, pack_lockfile); + + if (args.depth > 0) { + struct cache_time mtime; + char *shallow = git_path("shallow"); + int fd; + + mtime.sec = st.st_mtime; +#ifdef USE_NSEC + mtime.usec = st.st_mtim.usec; +#endif + if (stat(shallow, &st)) { + if (mtime.sec) + die("shallow file was removed during fetch"); + } else if (st.st_mtime != mtime.sec +#ifdef USE_NSEC + || st.st_mtim.usec != mtime.usec +#endif + ) + die("shallow file was changed during fetch"); + + fd = hold_lock_file_for_update(&lock, shallow, + LOCK_DIE_ON_ERROR); + if (!write_shallow_commits(fd, 0)) { + unlink(shallow); + rollback_lock_file(&lock); + } else { + commit_lock_file(&lock); + } + } + + reprepare_packed_git(); + return ref_cpy; +} |