#include "git-compat-util.h" #include "bundle-uri.h" #include "bundle.h" #include "copy.h" #include "environment.h" #include "gettext.h" #include "refs.h" #include "run-command.h" #include "hashmap.h" #include "pkt-line.h" #include "config.h" #include "remote.h" static struct { enum bundle_list_heuristic heuristic; const char *name; } heuristics[BUNDLE_HEURISTIC__COUNT] = { { BUNDLE_HEURISTIC_NONE, ""}, { BUNDLE_HEURISTIC_CREATIONTOKEN, "creationToken" }, }; static int compare_bundles(const void *hashmap_cmp_fn_data UNUSED, const struct hashmap_entry *he1, const struct hashmap_entry *he2, const void *id) { const struct remote_bundle_info *e1 = container_of(he1, const struct remote_bundle_info, ent); const struct remote_bundle_info *e2 = container_of(he2, const struct remote_bundle_info, ent); return strcmp(e1->id, id ? (const char *)id : e2->id); } void init_bundle_list(struct bundle_list *list) { memset(list, 0, sizeof(*list)); /* Implied defaults. */ list->mode = BUNDLE_MODE_ALL; list->version = 1; hashmap_init(&list->bundles, compare_bundles, NULL, 0); } static int clear_remote_bundle_info(struct remote_bundle_info *bundle, void *data UNUSED) { FREE_AND_NULL(bundle->id); FREE_AND_NULL(bundle->uri); FREE_AND_NULL(bundle->file); bundle->unbundled = 0; return 0; } void clear_bundle_list(struct bundle_list *list) { if (!list) return; for_all_bundles_in_list(list, clear_remote_bundle_info, NULL); hashmap_clear_and_free(&list->bundles, struct remote_bundle_info, ent); free(list->baseURI); } int for_all_bundles_in_list(struct bundle_list *list, bundle_iterator iter, void *data) { struct remote_bundle_info *info; struct hashmap_iter i; hashmap_for_each_entry(&list->bundles, &i, info, ent) { int result = iter(info, data); if (result) return result; } return 0; } static int summarize_bundle(struct remote_bundle_info *info, void *data) { FILE *fp = data; fprintf(fp, "[bundle \"%s\"]\n", info->id); fprintf(fp, "\turi = %s\n", info->uri); if (info->creationToken) fprintf(fp, "\tcreationToken = %"PRIu64"\n", info->creationToken); return 0; } void print_bundle_list(FILE *fp, struct bundle_list *list) { const char *mode; switch (list->mode) { case BUNDLE_MODE_ALL: mode = "all"; break; case BUNDLE_MODE_ANY: mode = "any"; break; case BUNDLE_MODE_NONE: default: mode = ""; } fprintf(fp, "[bundle]\n"); fprintf(fp, "\tversion = %d\n", list->version); fprintf(fp, "\tmode = %s\n", mode); if (list->heuristic) { int i; for (i = 0; i < BUNDLE_HEURISTIC__COUNT; i++) { if (heuristics[i].heuristic == list->heuristic) { printf("\theuristic = %s\n", heuristics[list->heuristic].name); break; } } } for_all_bundles_in_list(list, summarize_bundle, fp); } /** * Given a key-value pair, update the state of the given bundle list. * Returns 0 if the key-value pair is understood. Returns -1 if the key * is not understood or the value is malformed. */ static int bundle_list_update(const char *key, const char *value, struct bundle_list *list) { struct strbuf id = STRBUF_INIT; struct remote_bundle_info lookup = REMOTE_BUNDLE_INFO_INIT; struct remote_bundle_info *bundle; const char *subsection, *subkey; size_t subsection_len; if (parse_config_key(key, "bundle", &subsection, &subsection_len, &subkey)) return -1; if (!subsection_len) { if (!strcmp(subkey, "version")) { int version; if (!git_parse_int(value, &version)) return -1; if (version != 1) return -1; list->version = version; return 0; } if (!strcmp(subkey, "mode")) { if (!strcmp(value, "all")) list->mode = BUNDLE_MODE_ALL; else if (!strcmp(value, "any")) list->mode = BUNDLE_MODE_ANY; else return -1; return 0; } if (!strcmp(subkey, "heuristic")) { int i; for (i = 0; i < BUNDLE_HEURISTIC__COUNT; i++) { if (heuristics[i].heuristic && heuristics[i].name && !strcmp(value, heuristics[i].name)) { list->heuristic = heuristics[i].heuristic; return 0; } } /* Ignore unknown heuristics. */ return 0; } /* Ignore other unknown global keys. */ return 0; } strbuf_add(&id, subsection, subsection_len); /* * Check for an existing bundle with this , or create one * if necessary. */ lookup.id = id.buf; hashmap_entry_init(&lookup.ent, strhash(lookup.id)); if (!(bundle = hashmap_get_entry(&list->bundles, &lookup, ent, NULL))) { CALLOC_ARRAY(bundle, 1); bundle->id = strbuf_detach(&id, NULL); hashmap_entry_init(&bundle->ent, strhash(bundle->id)); hashmap_add(&list->bundles, &bundle->ent); } strbuf_release(&id); if (!strcmp(subkey, "uri")) { if (bundle->uri) return -1; bundle->uri = relative_url(list->baseURI, value, NULL); return 0; } if (!strcmp(subkey, "creationtoken")) { if (sscanf(value, "%"PRIu64, &bundle->creationToken) != 1) warning(_("could not parse bundle list key %s with value '%s'"), "creationToken", value); return 0; } /* * At this point, we ignore any information that we don't * understand, assuming it to be hints for a heuristic the client * does not currently understand. */ return 0; } static int config_to_bundle_list(const char *key, const char *value, const struct config_context *ctx UNUSED, void *data) { struct bundle_list *list = data; return bundle_list_update(key, value, list); } int bundle_uri_parse_config_format(const char *uri, const char *filename, struct bundle_list *list) { int result; struct config_options opts = { .error_action = CONFIG_ERROR_ERROR, }; if (!list->baseURI) { struct strbuf baseURI = STRBUF_INIT; strbuf_addstr(&baseURI, uri); /* * If the URI does not end with a trailing slash, then * remove the filename portion of the path. This is * important for relative URIs. */ strbuf_strip_file_from_path(&baseURI); list->baseURI = strbuf_detach(&baseURI, NULL); } result = git_config_from_file_with_options(config_to_bundle_list, filename, list, CONFIG_SCOPE_UNKNOWN, &opts); if (!result && list->mode == BUNDLE_MODE_NONE) { warning(_("bundle list at '%s' has no mode"), uri); result = 1; } return result; } static char *find_temp_filename(void) { int fd; struct strbuf name = STRBUF_INIT; /* * Find a temporary filename that is available. This is briefly * racy, but unlikely to collide. */ fd = odb_mkstemp(&name, "bundles/tmp_uri_XXXXXX"); if (fd < 0) { warning(_("failed to create temporary file")); return NULL; } close(fd); unlink(name.buf); return strbuf_detach(&name, NULL); } static int download_https_uri_to_file(const char *file, const char *uri) { int result = 0; struct child_process cp = CHILD_PROCESS_INIT; FILE *child_in = NULL, *child_out = NULL; struct strbuf line = STRBUF_INIT; int found_get = 0; strvec_pushl(&cp.args, "git-remote-https", uri, NULL); cp.err = -1; cp.in = -1; cp.out = -1; if (start_command(&cp)) return 1; child_in = fdopen(cp.in, "w"); if (!child_in) { result = 1; goto cleanup; } child_out = fdopen(cp.out, "r"); if (!child_out) { result = 1; goto cleanup; } fprintf(child_in, "capabilities\n"); fflush(child_in); while (!strbuf_getline(&line, child_out)) { if (!line.len) break; if (!strcmp(line.buf, "get")) found_get = 1; } strbuf_release(&line); if (!found_get) { result = error(_("insufficient capabilities")); goto cleanup; } fprintf(child_in, "get %s %s\n\n", uri, file); cleanup: if (child_in) fclose(child_in); if (finish_command(&cp)) return 1; if (child_out) fclose(child_out); return result; } static int copy_uri_to_file(const char *filename, const char *uri) { const char *out; if (starts_with(uri, "https:") || starts_with(uri, "http:")) return download_https_uri_to_file(filename, uri); if (skip_prefix(uri, "file://", &out)) uri = out; /* Copy as a file */ return copy_file(filename, uri, 0); } static int unbundle_from_file(struct repository *r, const char *file) { int result = 0; int bundle_fd; struct bundle_header header = BUNDLE_HEADER_INIT; struct string_list_item *refname; struct strbuf bundle_ref = STRBUF_INIT; size_t bundle_prefix_len; if ((bundle_fd = read_bundle_header(file, &header)) < 0) return 1; /* * Skip the reachability walk here, since we will be adding * a reachable ref pointing to the new tips, which will reach * the prerequisite commits. */ if ((result = unbundle(r, &header, bundle_fd, NULL, VERIFY_BUNDLE_QUIET))) return 1; /* * Convert all refs/heads/ from the bundle into refs/bundles/ * in the local repository. */ strbuf_addstr(&bundle_ref, "refs/bundles/"); bundle_prefix_len = bundle_ref.len; for_each_string_list_item(refname, &header.references) { struct object_id *oid = refname->util; struct object_id old_oid; const char *branch_name; int has_old; if (!skip_prefix(refname->string, "refs/heads/", &branch_name)) continue; strbuf_setlen(&bundle_ref, bundle_prefix_len); strbuf_addstr(&bundle_ref, branch_name); has_old = !read_ref(bundle_ref.buf, &old_oid); update_ref("fetched bundle", bundle_ref.buf, oid, has_old ? &old_oid : NULL, REF_SKIP_OID_VERIFICATION, UPDATE_REFS_MSG_ON_ERR); } bundle_header_release(&header); return result; } struct bundle_list_context { struct repository *r; struct bundle_list *list; enum bundle_list_mode mode; int count; int depth; }; /* * This early definition is necessary because we use indirect recursion: * * While iterating through a bundle list that was downloaded as part * of fetch_bundle_uri_internal(), iterator methods eventually call it * again, but with depth + 1. */ static int fetch_bundle_uri_internal(struct repository *r, struct remote_bundle_info *bundle, int depth, struct bundle_list *list); static int download_bundle_to_file(struct remote_bundle_info *bundle, void *data) { int res; struct bundle_list_context *ctx = data; if (ctx->mode == BUNDLE_MODE_ANY && ctx->count) return 0; res = fetch_bundle_uri_internal(ctx->r, bundle, ctx->depth + 1, ctx->list); /* * Only increment count if the download succeeded. If our mode is * BUNDLE_MODE_ANY, then we will want to try other URIs in the * list in case they work instead. */ if (!res) ctx->count++; /* * To be opportunistic as possible, we continue iterating and * download as many bundles as we can, so we can apply the ones * that work, even in BUNDLE_MODE_ALL mode. */ return 0; } struct bundles_for_sorting { struct remote_bundle_info **items; size_t alloc; size_t nr; }; static int append_bundle(struct remote_bundle_info *bundle, void *data) { struct bundles_for_sorting *list = data; list->items[list->nr++] = bundle; return 0; } /** * For use in QSORT() to get a list sorted by creationToken * in decreasing order. */ static int compare_creation_token_decreasing(const void *va, const void *vb) { const struct remote_bundle_info * const *a = va; const struct remote_bundle_info * const *b = vb; if ((*a)->creationToken > (*b)->creationToken) return -1; if ((*a)->creationToken < (*b)->creationToken) return 1; return 0; } static int fetch_bundles_by_token(struct repository *r, struct bundle_list *list) { int cur; int move_direction = 0; const char *creationTokenStr; uint64_t maxCreationToken = 0, newMaxCreationToken = 0; struct bundle_list_context ctx = { .r = r, .list = list, .mode = list->mode, }; struct bundles_for_sorting bundles = { .alloc = hashmap_get_size(&list->bundles), }; ALLOC_ARRAY(bundles.items, bundles.alloc); for_all_bundles_in_list(list, append_bundle, &bundles); if (!bundles.nr) { free(bundles.items); return 0; } QSORT(bundles.items, bundles.nr, compare_creation_token_decreasing); /* * If fetch.bundleCreationToken exists, parses to a uint64t, and * is not strictly smaller than the maximum creation token in the * bundle list, then do not download any bundles. */ if (!repo_config_get_value(r, "fetch.bundlecreationtoken", &creationTokenStr) && sscanf(creationTokenStr, "%"PRIu64, &maxCreationToken) == 1 && bundles.items[0]->creationToken <= maxCreationToken) { free(bundles.items); return 0; } /* * Attempt to download and unbundle the minimum number of bundles by * creationToken in decreasing order. If we fail to unbundle (after * a successful download) then move to the next non-downloaded bundle * and attempt downloading. Once we succeed in applying a bundle, * move to the previous unapplied bundle and attempt to unbundle it * again. * * In the case of a fresh clone, we will likely download all of the * bundles before successfully unbundling the oldest one, then the * rest of the bundles unbundle successfully in increasing order * of creationToken. * * If there are existing objects, then this process may terminate * early when all required commits from "new" bundles exist in the * repo's object store. */ cur = 0; while (cur >= 0 && cur < bundles.nr) { struct remote_bundle_info *bundle = bundles.items[cur]; /* * If we need to dig into bundles below the previous * creation token value, then likely we are in an erroneous * state due to missing or invalid bundles. Halt the process * instead of continuing to download extra data. */ if (bundle->creationToken <= maxCreationToken) break; if (!bundle->file) { /* * Not downloaded yet. Try downloading. * * Note that bundle->file is non-NULL if a download * was attempted, even if it failed to download. */ if (fetch_bundle_uri_internal(ctx.r, bundle, ctx.depth + 1, ctx.list)) { /* Mark as unbundled so we do not retry. */ bundle->unbundled = 1; /* Try looking deeper in the list. */ move_direction = 1; goto move; } /* We expect bundles when using creationTokens. */ if (!is_bundle(bundle->file, 1)) { warning(_("file downloaded from '%s' is not a bundle"), bundle->uri); break; } } if (bundle->file && !bundle->unbundled) { /* * This was downloaded, but not successfully * unbundled. Try unbundling again. */ if (unbundle_from_file(ctx.r, bundle->file)) { /* Try looking deeper in the list. */ move_direction = 1; } else { /* * Succeeded in unbundle. Retry bundles * that previously failed to unbundle. */ move_direction = -1; bundle->unbundled = 1; if (bundle->creationToken > newMaxCreationToken) newMaxCreationToken = bundle->creationToken; } } /* * Else case: downloaded and unbundled successfully. * Skip this by moving in the same direction as the * previous step. */ move: /* Move in the specified direction and repeat. */ cur += move_direction; } /* * We succeed if the loop terminates because 'cur' drops below * zero. The other case is that we terminate because 'cur' * reaches the end of the list, so we have a failure no matter * which bundles we apply from the list. */ if (cur < 0) { struct strbuf value = STRBUF_INIT; strbuf_addf(&value, "%"PRIu64"", newMaxCreationToken); if (repo_config_set_multivar_gently(ctx.r, "fetch.bundleCreationToken", value.buf, NULL, 0)) warning(_("failed to store maximum creation token")); strbuf_release(&value); } free(bundles.items); return cur >= 0; } static int download_bundle_list(struct repository *r, struct bundle_list *local_list, struct bundle_list *global_list, int depth) { struct bundle_list_context ctx = { .r = r, .list = global_list, .depth = depth + 1, .mode = local_list->mode, }; return for_all_bundles_in_list(local_list, download_bundle_to_file, &ctx); } static int fetch_bundle_list_in_config_format(struct repository *r, struct bundle_list *global_list, struct remote_bundle_info *bundle, int depth) { int result; struct bundle_list list_from_bundle; init_bundle_list(&list_from_bundle); if ((result = bundle_uri_parse_config_format(bundle->uri, bundle->file, &list_from_bundle))) goto cleanup; if (list_from_bundle.mode == BUNDLE_MODE_NONE) { warning(_("unrecognized bundle mode from URI '%s'"), bundle->uri); result = -1; goto cleanup; } /* * If this list uses the creationToken heuristic, then the URIs * it advertises are expected to be bundles, not nested lists. * We can drop 'global_list' and 'depth'. */ if (list_from_bundle.heuristic == BUNDLE_HEURISTIC_CREATIONTOKEN) { result = fetch_bundles_by_token(r, &list_from_bundle); global_list->heuristic = BUNDLE_HEURISTIC_CREATIONTOKEN; } else if ((result = download_bundle_list(r, &list_from_bundle, global_list, depth))) goto cleanup; cleanup: clear_bundle_list(&list_from_bundle); return result; } /** * This limits the recursion on fetch_bundle_uri_internal() when following * bundle lists. */ static int max_bundle_uri_depth = 4; /** * Recursively download all bundles advertised at the given URI * to files. If the file is a bundle, then add it to the given * 'list'. Otherwise, expect a bundle list and recurse on the * URIs in that list according to the list mode (ANY or ALL). */ static int fetch_bundle_uri_internal(struct repository *r, struct remote_bundle_info *bundle, int depth, struct bundle_list *list) { int result = 0; struct remote_bundle_info *bcopy; if (depth >= max_bundle_uri_depth) { warning(_("exceeded bundle URI recursion limit (%d)"), max_bundle_uri_depth); return -1; } if (!bundle->file && !(bundle->file = find_temp_filename())) { result = -1; goto cleanup; } if ((result = copy_uri_to_file(bundle->file, bundle->uri))) { warning(_("failed to download bundle from URI '%s'"), bundle->uri); goto cleanup; } if ((result = !is_bundle(bundle->file, 1))) { result = fetch_bundle_list_in_config_format( r, list, bundle, depth); if (result) warning(_("file at URI '%s' is not a bundle or bundle list"), bundle->uri); goto cleanup; } /* Copy the bundle and insert it into the global list. */ CALLOC_ARRAY(bcopy, 1); bcopy->id = xstrdup(bundle->id); bcopy->file = xstrdup(bundle->file); hashmap_entry_init(&bcopy->ent, strhash(bcopy->id)); hashmap_add(&list->bundles, &bcopy->ent); cleanup: if (result && bundle->file) unlink(bundle->file); return result; } /** * This loop iterator breaks the loop with nonzero return code on the * first successful unbundling of a bundle. */ static int attempt_unbundle(struct remote_bundle_info *info, void *data) { struct repository *r = data; if (!info->file || info->unbundled) return 0; if (!unbundle_from_file(r, info->file)) { info->unbundled = 1; return 1; } return 0; } static int unbundle_all_bundles(struct repository *r, struct bundle_list *list) { /* * Iterate through all bundles looking for ones that can * successfully unbundle. If any succeed, then perhaps another * will succeed in the next attempt. * * Keep in mind that a non-zero result for the loop here means * the loop terminated early on a successful unbundling, which * signals that we can try again. */ while (for_all_bundles_in_list(list, attempt_unbundle, r)) ; return 0; } static int unlink_bundle(struct remote_bundle_info *info, void *data UNUSED) { if (info->file) unlink_or_warn(info->file); return 0; } int fetch_bundle_uri(struct repository *r, const char *uri, int *has_heuristic) { int result; struct bundle_list list; struct remote_bundle_info bundle = { .uri = xstrdup(uri), .id = xstrdup(""), }; init_bundle_list(&list); /* * Do not fetch an empty bundle URI. An empty bundle URI * could signal that a configured bundle URI has been disabled. */ if (!*uri) { result = 0; goto cleanup; } /* If a bundle is added to this global list, then it is required. */ list.mode = BUNDLE_MODE_ALL; if ((result = fetch_bundle_uri_internal(r, &bundle, 0, &list))) goto cleanup; result = unbundle_all_bundles(r, &list); cleanup: if (has_heuristic) *has_heuristic = (list.heuristic != BUNDLE_HEURISTIC_NONE); for_all_bundles_in_list(&list, unlink_bundle, NULL); clear_bundle_list(&list); clear_remote_bundle_info(&bundle, NULL); return result; } int fetch_bundle_list(struct repository *r, struct bundle_list *list) { int result; struct bundle_list global_list; /* * If the creationToken heuristic is used, then the URIs * advertised by 'list' are not nested lists and instead * direct bundles. We do not need to use global_list. */ if (list->heuristic == BUNDLE_HEURISTIC_CREATIONTOKEN) return fetch_bundles_by_token(r, list); init_bundle_list(&global_list); /* If a bundle is added to this global list, then it is required. */ global_list.mode = BUNDLE_MODE_ALL; if ((result = download_bundle_list(r, list, &global_list, 0))) goto cleanup; if (list->heuristic == BUNDLE_HEURISTIC_CREATIONTOKEN) result = fetch_bundles_by_token(r, list); else result = unbundle_all_bundles(r, &global_list); cleanup: for_all_bundles_in_list(&global_list, unlink_bundle, NULL); clear_bundle_list(&global_list); return result; } /** * API for serve.c. */ int bundle_uri_advertise(struct repository *r, struct strbuf *value UNUSED) { static int advertise_bundle_uri = -1; if (advertise_bundle_uri != -1) goto cached; advertise_bundle_uri = 0; repo_config_get_maybe_bool(r, "uploadpack.advertisebundleuris", &advertise_bundle_uri); cached: return advertise_bundle_uri; } static int config_to_packet_line(const char *key, const char *value, const struct config_context *ctx UNUSED, void *data) { struct packet_reader *writer = data; if (starts_with(key, "bundle.")) packet_write_fmt(writer->fd, "%s=%s", key, value); return 0; } int bundle_uri_command(struct repository *r, struct packet_reader *request) { struct packet_writer writer; packet_writer_init(&writer, 1); while (packet_reader_read(request) == PACKET_READ_NORMAL) die(_("bundle-uri: unexpected argument: '%s'"), request->line); if (request->status != PACKET_READ_FLUSH) die(_("bundle-uri: expected flush after arguments")); /* * Read all "bundle.*" config lines to the client as key=value * packet lines. */ repo_config(r, config_to_packet_line, &writer); packet_writer_flush(&writer); return 0; } /** * General API for {transport,connect}.c etc. */ int bundle_uri_parse_line(struct bundle_list *list, const char *line) { int result; const char *equals; struct strbuf key = STRBUF_INIT; if (!strlen(line)) return error(_("bundle-uri: got an empty line")); equals = strchr(line, '='); if (!equals) return error(_("bundle-uri: line is not of the form 'key=value'")); if (line == equals || !*(equals + 1)) return error(_("bundle-uri: line has empty key or value")); strbuf_add(&key, line, equals - line); result = bundle_list_update(key.buf, equals + 1, list); strbuf_release(&key); return result; }