diff options
Diffstat (limited to 'refs.c')
| -rw-r--r-- | refs.c | 2336 |
1 files changed, 2336 insertions, 0 deletions
diff --git a/refs.c b/refs.c new file mode 100644 index 000000000000..cd297ee4bdbe --- /dev/null +++ b/refs.c @@ -0,0 +1,2336 @@ +/* + * The backend-independent part of the reference module. + */ + +#include "cache.h" +#include "config.h" +#include "hashmap.h" +#include "lockfile.h" +#include "iterator.h" +#include "refs.h" +#include "refs/refs-internal.h" +#include "object-store.h" +#include "object.h" +#include "tag.h" +#include "submodule.h" +#include "worktree.h" +#include "argv-array.h" +#include "repository.h" + +/* + * List of all available backends + */ +static struct ref_storage_be *refs_backends = &refs_be_files; + +static struct ref_storage_be *find_ref_storage_backend(const char *name) +{ + struct ref_storage_be *be; + for (be = refs_backends; be; be = be->next) + if (!strcmp(be->name, name)) + return be; + return NULL; +} + +int ref_storage_backend_exists(const char *name) +{ + return find_ref_storage_backend(name) != NULL; +} + +/* + * How to handle various characters in refnames: + * 0: An acceptable character for refs + * 1: End-of-component + * 2: ., look for a preceding . to reject .. in refs + * 3: {, look for a preceding @ to reject @{ in refs + * 4: A bad character: ASCII control characters, and + * ":", "?", "[", "\", "^", "~", SP, or TAB + * 5: *, reject unless REFNAME_REFSPEC_PATTERN is set + */ +static unsigned char refname_disposition[256] = { + 1, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, + 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, + 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5, 0, 0, 0, 2, 1, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 4, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 4, 0, 4, 0, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 4, 4 +}; + +/* + * Try to read one refname component from the front of refname. + * Return the length of the component found, or -1 if the component is + * not legal. It is legal if it is something reasonable to have under + * ".git/refs/"; We do not like it if: + * + * - it begins with ".", or + * - it has double dots "..", or + * - it has ASCII control characters, or + * - it has ":", "?", "[", "\", "^", "~", SP, or TAB anywhere, or + * - it has "*" anywhere unless REFNAME_REFSPEC_PATTERN is set, or + * - it ends with a "/", or + * - it ends with ".lock", or + * - it contains a "@{" portion + * + * When sanitized is not NULL, instead of rejecting the input refname + * as an error, try to come up with a usable replacement for the input + * refname in it. + */ +static int check_refname_component(const char *refname, int *flags, + struct strbuf *sanitized) +{ + const char *cp; + char last = '\0'; + size_t component_start = 0; /* garbage - not a reasonable initial value */ + + if (sanitized) + component_start = sanitized->len; + + for (cp = refname; ; cp++) { + int ch = *cp & 255; + unsigned char disp = refname_disposition[ch]; + + if (sanitized && disp != 1) + strbuf_addch(sanitized, ch); + + switch (disp) { + case 1: + goto out; + case 2: + if (last == '.') { /* Refname contains "..". */ + if (sanitized) + /* collapse ".." to single "." */ + strbuf_setlen(sanitized, sanitized->len - 1); + else + return -1; + } + break; + case 3: + if (last == '@') { /* Refname contains "@{". */ + if (sanitized) + sanitized->buf[sanitized->len-1] = '-'; + else + return -1; + } + break; + case 4: + /* forbidden char */ + if (sanitized) + sanitized->buf[sanitized->len-1] = '-'; + else + return -1; + break; + case 5: + if (!(*flags & REFNAME_REFSPEC_PATTERN)) { + /* refspec can't be a pattern */ + if (sanitized) + sanitized->buf[sanitized->len-1] = '-'; + else + return -1; + } + + /* + * Unset the pattern flag so that we only accept + * a single asterisk for one side of refspec. + */ + *flags &= ~ REFNAME_REFSPEC_PATTERN; + break; + } + last = ch; + } +out: + if (cp == refname) + return 0; /* Component has zero length. */ + + if (refname[0] == '.') { /* Component starts with '.'. */ + if (sanitized) + sanitized->buf[component_start] = '-'; + else + return -1; + } + if (cp - refname >= LOCK_SUFFIX_LEN && + !memcmp(cp - LOCK_SUFFIX_LEN, LOCK_SUFFIX, LOCK_SUFFIX_LEN)) { + if (!sanitized) + return -1; + /* Refname ends with ".lock". */ + while (strbuf_strip_suffix(sanitized, LOCK_SUFFIX)) { + /* try again in case we have .lock.lock */ + } + } + return cp - refname; +} + +static int check_or_sanitize_refname(const char *refname, int flags, + struct strbuf *sanitized) +{ + int component_len, component_count = 0; + + if (!strcmp(refname, "@")) { + /* Refname is a single character '@'. */ + if (sanitized) + strbuf_addch(sanitized, '-'); + else + return -1; + } + + while (1) { + if (sanitized && sanitized->len) + strbuf_complete(sanitized, '/'); + + /* We are at the start of a path component. */ + component_len = check_refname_component(refname, &flags, + sanitized); + if (sanitized && component_len == 0) + ; /* OK, omit empty component */ + else if (component_len <= 0) + return -1; + + component_count++; + if (refname[component_len] == '\0') + break; + /* Skip to next component. */ + refname += component_len + 1; + } + + if (refname[component_len - 1] == '.') { + /* Refname ends with '.'. */ + if (sanitized) + ; /* omit ending dot */ + else + return -1; + } + if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2) + return -1; /* Refname has only one component. */ + return 0; +} + +int check_refname_format(const char *refname, int flags) +{ + return check_or_sanitize_refname(refname, flags, NULL); +} + +void sanitize_refname_component(const char *refname, struct strbuf *out) +{ + if (check_or_sanitize_refname(refname, REFNAME_ALLOW_ONELEVEL, out)) + BUG("sanitizing refname '%s' check returned error", refname); +} + +int refname_is_safe(const char *refname) +{ + const char *rest; + + if (skip_prefix(refname, "refs/", &rest)) { + char *buf; + int result; + size_t restlen = strlen(rest); + + /* rest must not be empty, or start or end with "/" */ + if (!restlen || *rest == '/' || rest[restlen - 1] == '/') + return 0; + + /* + * Does the refname try to escape refs/? + * For example: refs/foo/../bar is safe but refs/foo/../../bar + * is not. + */ + buf = xmallocz(restlen); + result = !normalize_path_copy(buf, rest) && !strcmp(buf, rest); + free(buf); + return result; + } + + do { + if (!isupper(*refname) && *refname != '_') + return 0; + refname++; + } while (*refname); + return 1; +} + +/* + * Return true if refname, which has the specified oid and flags, can + * be resolved to an object in the database. If the referred-to object + * does not exist, emit a warning and return false. + */ +int ref_resolves_to_object(const char *refname, + const struct object_id *oid, + unsigned int flags) +{ + if (flags & REF_ISBROKEN) + return 0; + if (!has_object_file(oid)) { + error(_("%s does not point to a valid object!"), refname); + return 0; + } + return 1; +} + +char *refs_resolve_refdup(struct ref_store *refs, + const char *refname, int resolve_flags, + struct object_id *oid, int *flags) +{ + const char *result; + + result = refs_resolve_ref_unsafe(refs, refname, resolve_flags, + oid, flags); + return xstrdup_or_null(result); +} + +char *resolve_refdup(const char *refname, int resolve_flags, + struct object_id *oid, int *flags) +{ + return refs_resolve_refdup(get_main_ref_store(the_repository), + refname, resolve_flags, + oid, flags); +} + +/* The argument to filter_refs */ +struct ref_filter { + const char *pattern; + const char *prefix; + each_ref_fn *fn; + void *cb_data; +}; + +int refs_read_ref_full(struct ref_store *refs, const char *refname, + int resolve_flags, struct object_id *oid, int *flags) +{ + if (refs_resolve_ref_unsafe(refs, refname, resolve_flags, oid, flags)) + return 0; + return -1; +} + +int read_ref_full(const char *refname, int resolve_flags, struct object_id *oid, int *flags) +{ + return refs_read_ref_full(get_main_ref_store(the_repository), refname, + resolve_flags, oid, flags); +} + +int read_ref(const char *refname, struct object_id *oid) +{ + return read_ref_full(refname, RESOLVE_REF_READING, oid, NULL); +} + +static int refs_ref_exists(struct ref_store *refs, const char *refname) +{ + return !!refs_resolve_ref_unsafe(refs, refname, RESOLVE_REF_READING, NULL, NULL); +} + +int ref_exists(const char *refname) +{ + return refs_ref_exists(get_main_ref_store(the_repository), refname); +} + +static int match_ref_pattern(const char *refname, + const struct string_list_item *item) +{ + int matched = 0; + if (item->util == NULL) { + if (!wildmatch(item->string, refname, 0)) + matched = 1; + } else { + const char *rest; + if (skip_prefix(refname, item->string, &rest) && + (!*rest || *rest == '/')) + matched = 1; + } + return matched; +} + +int ref_filter_match(const char *refname, + const struct string_list *include_patterns, + const struct string_list *exclude_patterns) +{ + struct string_list_item *item; + + if (exclude_patterns && exclude_patterns->nr) { + for_each_string_list_item(item, exclude_patterns) { + if (match_ref_pattern(refname, item)) + return 0; + } + } + + if (include_patterns && include_patterns->nr) { + int found = 0; + for_each_string_list_item(item, include_patterns) { + if (match_ref_pattern(refname, item)) { + found = 1; + break; + } + } + + if (!found) + return 0; + } + return 1; +} + +static int filter_refs(const char *refname, const struct object_id *oid, + int flags, void *data) +{ + struct ref_filter *filter = (struct ref_filter *)data; + + if (wildmatch(filter->pattern, refname, 0)) + return 0; + if (filter->prefix) + skip_prefix(refname, filter->prefix, &refname); + return filter->fn(refname, oid, flags, filter->cb_data); +} + +enum peel_status peel_object(const struct object_id *name, struct object_id *oid) +{ + struct object *o = lookup_unknown_object(name); + + if (o->type == OBJ_NONE) { + int type = oid_object_info(the_repository, name, NULL); + if (type < 0 || !object_as_type(the_repository, o, type, 0)) + return PEEL_INVALID; + } + + if (o->type != OBJ_TAG) + return PEEL_NON_TAG; + + o = deref_tag_noverify(o); + if (!o) + return PEEL_INVALID; + + oidcpy(oid, &o->oid); + return PEEL_PEELED; +} + +struct warn_if_dangling_data { + FILE *fp; + const char *refname; + const struct string_list *refnames; + const char *msg_fmt; +}; + +static int warn_if_dangling_symref(const char *refname, const struct object_id *oid, + int flags, void *cb_data) +{ + struct warn_if_dangling_data *d = cb_data; + const char *resolves_to; + + if (!(flags & REF_ISSYMREF)) + return 0; + + resolves_to = resolve_ref_unsafe(refname, 0, NULL, NULL); + if (!resolves_to + || (d->refname + ? strcmp(resolves_to, d->refname) + : !string_list_has_string(d->refnames, resolves_to))) { + return 0; + } + + fprintf(d->fp, d->msg_fmt, refname); + fputc('\n', d->fp); + return 0; +} + +void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname) +{ + struct warn_if_dangling_data data; + + data.fp = fp; + data.refname = refname; + data.refnames = NULL; + data.msg_fmt = msg_fmt; + for_each_rawref(warn_if_dangling_symref, &data); +} + +void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames) +{ + struct warn_if_dangling_data data; + + data.fp = fp; + data.refname = NULL; + data.refnames = refnames; + data.msg_fmt = msg_fmt; + for_each_rawref(warn_if_dangling_symref, &data); +} + +int refs_for_each_tag_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data) +{ + return refs_for_each_ref_in(refs, "refs/tags/", fn, cb_data); +} + +int for_each_tag_ref(each_ref_fn fn, void *cb_data) +{ + return refs_for_each_tag_ref(get_main_ref_store(the_repository), fn, cb_data); +} + +int refs_for_each_branch_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data) +{ + return refs_for_each_ref_in(refs, "refs/heads/", fn, cb_data); +} + +int for_each_branch_ref(each_ref_fn fn, void *cb_data) +{ + return refs_for_each_branch_ref(get_main_ref_store(the_repository), fn, cb_data); +} + +int refs_for_each_remote_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data) +{ + return refs_for_each_ref_in(refs, "refs/remotes/", fn, cb_data); +} + +int for_each_remote_ref(each_ref_fn fn, void *cb_data) +{ + return refs_for_each_remote_ref(get_main_ref_store(the_repository), fn, cb_data); +} + +int head_ref_namespaced(each_ref_fn fn, void *cb_data) +{ + struct strbuf buf = STRBUF_INIT; + int ret = 0; + struct object_id oid; + int flag; + + strbuf_addf(&buf, "%sHEAD", get_git_namespace()); + if (!read_ref_full(buf.buf, RESOLVE_REF_READING, &oid, &flag)) + ret = fn(buf.buf, &oid, flag, cb_data); + strbuf_release(&buf); + + return ret; +} + +void normalize_glob_ref(struct string_list_item *item, const char *prefix, + const char *pattern) +{ + struct strbuf normalized_pattern = STRBUF_INIT; + + if (*pattern == '/') + BUG("pattern must not start with '/'"); + + if (prefix) { + strbuf_addstr(&normalized_pattern, prefix); + } + else if (!starts_with(pattern, "refs/")) + strbuf_addstr(&normalized_pattern, "refs/"); + strbuf_addstr(&normalized_pattern, pattern); + strbuf_strip_suffix(&normalized_pattern, "/"); + + item->string = strbuf_detach(&normalized_pattern, NULL); + item->util = has_glob_specials(pattern) ? NULL : item->string; + strbuf_release(&normalized_pattern); +} + +int for_each_glob_ref_in(each_ref_fn fn, const char *pattern, + const char *prefix, void *cb_data) +{ + struct strbuf real_pattern = STRBUF_INIT; + struct ref_filter filter; + int ret; + + if (!prefix && !starts_with(pattern, "refs/")) + strbuf_addstr(&real_pattern, "refs/"); + else if (prefix) + strbuf_addstr(&real_pattern, prefix); + strbuf_addstr(&real_pattern, pattern); + + if (!has_glob_specials(pattern)) { + /* Append implied '/' '*' if not present. */ + strbuf_complete(&real_pattern, '/'); + /* No need to check for '*', there is none. */ + strbuf_addch(&real_pattern, '*'); + } + + filter.pattern = real_pattern.buf; + filter.prefix = prefix; + filter.fn = fn; + filter.cb_data = cb_data; + ret = for_each_ref(filter_refs, &filter); + + strbuf_release(&real_pattern); + return ret; +} + +int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data) +{ + return for_each_glob_ref_in(fn, pattern, NULL, cb_data); +} + +const char *prettify_refname(const char *name) +{ + if (skip_prefix(name, "refs/heads/", &name) || + skip_prefix(name, "refs/tags/", &name) || + skip_prefix(name, "refs/remotes/", &name)) + ; /* nothing */ + return name; +} + +static const char *ref_rev_parse_rules[] = { + "%.*s", + "refs/%.*s", + "refs/tags/%.*s", + "refs/heads/%.*s", + "refs/remotes/%.*s", + "refs/remotes/%.*s/HEAD", + NULL +}; + +#define NUM_REV_PARSE_RULES (ARRAY_SIZE(ref_rev_parse_rules) - 1) + +/* + * Is it possible that the caller meant full_name with abbrev_name? + * If so return a non-zero value to signal "yes"; the magnitude of + * the returned value gives the precedence used for disambiguation. + * + * If abbrev_name cannot mean full_name, return 0. + */ +int refname_match(const char *abbrev_name, const char *full_name) +{ + const char **p; + const int abbrev_name_len = strlen(abbrev_name); + const int num_rules = NUM_REV_PARSE_RULES; + + for (p = ref_rev_parse_rules; *p; p++) + if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) + return &ref_rev_parse_rules[num_rules] - p; + + return 0; +} + +/* + * Given a 'prefix' expand it by the rules in 'ref_rev_parse_rules' and add + * the results to 'prefixes' + */ +void expand_ref_prefix(struct argv_array *prefixes, const char *prefix) +{ + const char **p; + int len = strlen(prefix); + + for (p = ref_rev_parse_rules; *p; p++) + argv_array_pushf(prefixes, *p, len, prefix); +} + +/* + * *string and *len will only be substituted, and *string returned (for + * later free()ing) if the string passed in is a magic short-hand form + * to name a branch. + */ +static char *substitute_branch_name(struct repository *r, + const char **string, int *len) +{ + struct strbuf buf = STRBUF_INIT; + int ret = repo_interpret_branch_name(r, *string, *len, &buf, 0); + + if (ret == *len) { + size_t size; + *string = strbuf_detach(&buf, &size); + *len = size; + return (char *)*string; + } + + return NULL; +} + +int repo_dwim_ref(struct repository *r, const char *str, int len, + struct object_id *oid, char **ref) +{ + char *last_branch = substitute_branch_name(r, &str, &len); + int refs_found = expand_ref(r, str, len, oid, ref); + free(last_branch); + return refs_found; +} + +int dwim_ref(const char *str, int len, struct object_id *oid, char **ref) +{ + return repo_dwim_ref(the_repository, str, len, oid, ref); +} + +int expand_ref(struct repository *repo, const char *str, int len, + struct object_id *oid, char **ref) +{ + const char **p, *r; + int refs_found = 0; + struct strbuf fullref = STRBUF_INIT; + + *ref = NULL; + for (p = ref_rev_parse_rules; *p; p++) { + struct object_id oid_from_ref; + struct object_id *this_result; + int flag; + + this_result = refs_found ? &oid_from_ref : oid; + strbuf_reset(&fullref); + strbuf_addf(&fullref, *p, len, str); + r = refs_resolve_ref_unsafe(get_main_ref_store(repo), + fullref.buf, RESOLVE_REF_READING, + this_result, &flag); + if (r) { + if (!refs_found++) + *ref = xstrdup(r); + if (!warn_ambiguous_refs) + break; + } else if ((flag & REF_ISSYMREF) && strcmp(fullref.buf, "HEAD")) { + warning(_("ignoring dangling symref %s"), fullref.buf); + } else if ((flag & REF_ISBROKEN) && strchr(fullref.buf, '/')) { + warning(_("ignoring broken ref %s"), fullref.buf); + } + } + strbuf_release(&fullref); + return refs_found; +} + +int repo_dwim_log(struct repository *r, const char *str, int len, + struct object_id *oid, char **log) +{ + struct ref_store *refs = get_main_ref_store(r); + char *last_branch = substitute_branch_name(r, &str, &len); + const char **p; + int logs_found = 0; + struct strbuf path = STRBUF_INIT; + + *log = NULL; + for (p = ref_rev_parse_rules; *p; p++) { + struct object_id hash; + const char *ref, *it; + + strbuf_reset(&path); + strbuf_addf(&path, *p, len, str); + ref = refs_resolve_ref_unsafe(refs, path.buf, + RESOLVE_REF_READING, + &hash, NULL); + if (!ref) + continue; + if (refs_reflog_exists(refs, path.buf)) + it = path.buf; + else if (strcmp(ref, path.buf) && + refs_reflog_exists(refs, ref)) + it = ref; + else + continue; + if (!logs_found++) { + *log = xstrdup(it); + oidcpy(oid, &hash); + } + if (!warn_ambiguous_refs) + break; + } + strbuf_release(&path); + free(last_branch); + return logs_found; +} + +int dwim_log(const char *str, int len, struct object_id *oid, char **log) +{ + return repo_dwim_log(the_repository, str, len, oid, log); +} + +static int is_per_worktree_ref(const char *refname) +{ + return !strcmp(refname, "HEAD") || + starts_with(refname, "refs/worktree/") || + starts_with(refname, "refs/bisect/") || + starts_with(refname, "refs/rewritten/"); +} + +static int is_pseudoref_syntax(const char *refname) +{ + const char *c; + + for (c = refname; *c; c++) { + if (!isupper(*c) && *c != '-' && *c != '_') + return 0; + } + + return 1; +} + +static int is_main_pseudoref_syntax(const char *refname) +{ + return skip_prefix(refname, "main-worktree/", &refname) && + *refname && + is_pseudoref_syntax(refname); +} + +static int is_other_pseudoref_syntax(const char *refname) +{ + if (!skip_prefix(refname, "worktrees/", &refname)) + return 0; + refname = strchr(refname, '/'); + if (!refname || !refname[1]) + return 0; + return is_pseudoref_syntax(refname + 1); +} + +enum ref_type ref_type(const char *refname) +{ + if (is_per_worktree_ref(refname)) + return REF_TYPE_PER_WORKTREE; + if (is_pseudoref_syntax(refname)) + return REF_TYPE_PSEUDOREF; + if (is_main_pseudoref_syntax(refname)) + return REF_TYPE_MAIN_PSEUDOREF; + if (is_other_pseudoref_syntax(refname)) + return REF_TYPE_OTHER_PSEUDOREF; + return REF_TYPE_NORMAL; +} + +long get_files_ref_lock_timeout_ms(void) +{ + static int configured = 0; + + /* The default timeout is 100 ms: */ + static int timeout_ms = 100; + + if (!configured) { + git_config_get_int("core.filesreflocktimeout", &timeout_ms); + configured = 1; + } + + return timeout_ms; +} + +static int write_pseudoref(const char *pseudoref, const struct object_id *oid, + const struct object_id *old_oid, struct strbuf *err) +{ + const char *filename; + int fd; + struct lock_file lock = LOCK_INIT; + struct strbuf buf = STRBUF_INIT; + int ret = -1; + + if (!oid) + return 0; + + strbuf_addf(&buf, "%s\n", oid_to_hex(oid)); + + filename = git_path("%s", pseudoref); + fd = hold_lock_file_for_update_timeout(&lock, filename, 0, + get_files_ref_lock_timeout_ms()); + if (fd < 0) { + strbuf_addf(err, _("could not open '%s' for writing: %s"), + filename, strerror(errno)); + goto done; + } + + if (old_oid) { + struct object_id actual_old_oid; + + if (read_ref(pseudoref, &actual_old_oid)) { + if (!is_null_oid(old_oid)) { + strbuf_addf(err, _("could not read ref '%s'"), + pseudoref); + rollback_lock_file(&lock); + goto done; + } + } else if (is_null_oid(old_oid)) { + strbuf_addf(err, _("ref '%s' already exists"), + pseudoref); + rollback_lock_file(&lock); + goto done; + } else if (!oideq(&actual_old_oid, old_oid)) { + strbuf_addf(err, _("unexpected object ID when writing '%s'"), + pseudoref); + rollback_lock_file(&lock); + goto done; + } + } + + if (write_in_full(fd, buf.buf, buf.len) < 0) { + strbuf_addf(err, _("could not write to '%s'"), filename); + rollback_lock_file(&lock); + goto done; + } + + commit_lock_file(&lock); + ret = 0; +done: + strbuf_release(&buf); + return ret; +} + +static int delete_pseudoref(const char *pseudoref, const struct object_id *old_oid) +{ + const char *filename; + + filename = git_path("%s", pseudoref); + + if (old_oid && !is_null_oid(old_oid)) { + struct lock_file lock = LOCK_INIT; + int fd; + struct object_id actual_old_oid; + + fd = hold_lock_file_for_update_timeout( + &lock, filename, 0, + get_files_ref_lock_timeout_ms()); + if (fd < 0) { + error_errno(_("could not open '%s' for writing"), + filename); + return -1; + } + if (read_ref(pseudoref, &actual_old_oid)) + die(_("could not read ref '%s'"), pseudoref); + if (!oideq(&actual_old_oid, old_oid)) { + error(_("unexpected object ID when deleting '%s'"), + pseudoref); + rollback_lock_file(&lock); + return -1; + } + + unlink(filename); + rollback_lock_file(&lock); + } else { + unlink(filename); + } + + return 0; +} + +int refs_delete_ref(struct ref_store *refs, const char *msg, + const char *refname, + const struct object_id *old_oid, + unsigned int flags) +{ + struct ref_transaction *transaction; + struct strbuf err = STRBUF_INIT; + + if (ref_type(refname) == REF_TYPE_PSEUDOREF) { + assert(refs == get_main_ref_store(the_repository)); + return delete_pseudoref(refname, old_oid); + } + + transaction = ref_store_transaction_begin(refs, &err); + if (!transaction || + ref_transaction_delete(transaction, refname, old_oid, + flags, msg, &err) || + ref_transaction_commit(transaction, &err)) { + error("%s", err.buf); + ref_transaction_free(transaction); + strbuf_release(&err); + return 1; + } + ref_transaction_free(transaction); + strbuf_release(&err); + return 0; +} + +int delete_ref(const char *msg, const char *refname, + const struct object_id *old_oid, unsigned int flags) +{ + return refs_delete_ref(get_main_ref_store(the_repository), msg, refname, + old_oid, flags); +} + +void copy_reflog_msg(struct strbuf *sb, const char *msg) +{ + char c; + int wasspace = 1; + + strbuf_addch(sb, '\t'); + while ((c = *msg++)) { + if (wasspace && isspace(c)) + continue; + wasspace = isspace(c); + if (wasspace) + c = ' '; + strbuf_addch(sb, c); + } + strbuf_rtrim(sb); +} + +int should_autocreate_reflog(const char *refname) +{ + switch (log_all_ref_updates) { + case LOG_REFS_ALWAYS: + return 1; + case LOG_REFS_NORMAL: + return starts_with(refname, "refs/heads/") || + starts_with(refname, "refs/remotes/") || + starts_with(refname, "refs/notes/") || + !strcmp(refname, "HEAD"); + default: + return 0; + } +} + +int is_branch(const char *refname) +{ + return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/"); +} + +struct read_ref_at_cb { + const char *refname; + timestamp_t at_time; + int cnt; + int reccnt; + struct object_id *oid; + int found_it; + + struct object_id ooid; + struct object_id noid; + int tz; + timestamp_t date; + char **msg; + timestamp_t *cutoff_time; + int *cutoff_tz; + int *cutoff_cnt; +}; + +static int read_ref_at_ent(struct object_id *ooid, struct object_id *noid, + const char *email, timestamp_t timestamp, int tz, + const char *message, void *cb_data) +{ + struct read_ref_at_cb *cb = cb_data; + + cb->reccnt++; + cb->tz = tz; + cb->date = timestamp; + + if (timestamp <= cb->at_time || cb->cnt == 0) { + if (cb->msg) + *cb->msg = xstrdup(message); + if (cb->cutoff_time) + *cb->cutoff_time = timestamp; + if (cb->cutoff_tz) + *cb->cutoff_tz = tz; + if (cb->cutoff_cnt) + *cb->cutoff_cnt = cb->reccnt - 1; + /* + * we have not yet updated cb->[n|o]oid so they still + * hold the values for the previous record. + */ + if (!is_null_oid(&cb->ooid)) { + oidcpy(cb->oid, noid); + if (!oideq(&cb->ooid, noid)) + warning(_("log for ref %s has gap after %s"), + cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822))); + } + else if (cb->date == cb->at_time) + oidcpy(cb->oid, noid); + else if (!oideq(noid, cb->oid)) + warning(_("log for ref %s unexpectedly ended on %s"), + cb->refname, show_date(cb->date, cb->tz, + DATE_MODE(RFC2822))); + oidcpy(&cb->ooid, ooid); + oidcpy(&cb->noid, noid); + cb->found_it = 1; + return 1; + } + oidcpy(&cb->ooid, ooid); + oidcpy(&cb->noid, noid); + if (cb->cnt > 0) + cb->cnt--; + return 0; +} + +static int read_ref_at_ent_oldest(struct object_id *ooid, struct object_id *noid, + const char *email, timestamp_t timestamp, + int tz, const char *message, void *cb_data) +{ + struct read_ref_at_cb *cb = cb_data; + + if (cb->msg) + *cb->msg = xstrdup(message); + if (cb->cutoff_time) + *cb->cutoff_time = timestamp; + if (cb->cutoff_tz) + *cb->cutoff_tz = tz; + if (cb->cutoff_cnt) + *cb->cutoff_cnt = cb->reccnt; + oidcpy(cb->oid, ooid); + if (is_null_oid(cb->oid)) + oidcpy(cb->oid, noid); + /* We just want the first entry */ + return 1; +} + +int read_ref_at(struct ref_store *refs, const char *refname, + unsigned int flags, timestamp_t at_time, int cnt, + struct object_id *oid, char **msg, + timestamp_t *cutoff_time, int *cutoff_tz, int *cutoff_cnt) +{ + struct read_ref_at_cb cb; + + memset(&cb, 0, sizeof(cb)); + cb.refname = refname; + cb.at_time = at_time; + cb.cnt = cnt; + cb.msg = msg; + cb.cutoff_time = cutoff_time; + cb.cutoff_tz = cutoff_tz; + cb.cutoff_cnt = cutoff_cnt; + cb.oid = oid; + + refs_for_each_reflog_ent_reverse(refs, refname, read_ref_at_ent, &cb); + + if (!cb.reccnt) { + if (flags & GET_OID_QUIETLY) + exit(128); + else + die(_("log for %s is empty"), refname); + } + if (cb.found_it) + return 0; + + refs_for_each_reflog_ent(refs, refname, read_ref_at_ent_oldest, &cb); + + return 1; +} + +struct ref_transaction *ref_store_transaction_begin(struct ref_store *refs, + struct strbuf *err) +{ + struct ref_transaction *tr; + assert(err); + + tr = xcalloc(1, sizeof(struct ref_transaction)); + tr->ref_store = refs; + return tr; +} + +struct ref_transaction *ref_transaction_begin(struct strbuf *err) +{ + return ref_store_transaction_begin(get_main_ref_store(the_repository), err); +} + +void ref_transaction_free(struct ref_transaction *transaction) +{ + size_t i; + + if (!transaction) + return; + + switch (transaction->state) { + case REF_TRANSACTION_OPEN: + case REF_TRANSACTION_CLOSED: + /* OK */ + break; + case REF_TRANSACTION_PREPARED: + BUG("free called on a prepared reference transaction"); + break; + default: + BUG("unexpected reference transaction state"); + break; + } + + for (i = 0; i < transaction->nr; i++) { + free(transaction->updates[i]->msg); + free(transaction->updates[i]); + } + free(transaction->updates); + free(transaction); +} + +struct ref_update *ref_transaction_add_update( + struct ref_transaction *transaction, + const char *refname, unsigned int flags, + const struct object_id *new_oid, + const struct object_id *old_oid, + const char *msg) +{ + struct ref_update *update; + + if (transaction->state != REF_TRANSACTION_OPEN) + BUG("update called for transaction that is not open"); + + FLEX_ALLOC_STR(update, refname, refname); + ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc); + transaction->updates[transaction->nr++] = update; + + update->flags = flags; + + if (flags & REF_HAVE_NEW) + oidcpy(&update->new_oid, new_oid); + if (flags & REF_HAVE_OLD) + oidcpy(&update->old_oid, old_oid); + update->msg = xstrdup_or_null(msg); + return update; +} + +int ref_transaction_update(struct ref_transaction *transaction, + const char *refname, + const struct object_id *new_oid, + const struct object_id *old_oid, + unsigned int flags, const char *msg, + struct strbuf *err) +{ + assert(err); + + if ((new_oid && !is_null_oid(new_oid)) ? + check_refname_format(refname, REFNAME_ALLOW_ONELEVEL) : + !refname_is_safe(refname)) { + strbuf_addf(err, _("refusing to update ref with bad name '%s'"), + refname); + return -1; + } + + if (flags & ~REF_TRANSACTION_UPDATE_ALLOWED_FLAGS) + BUG("illegal flags 0x%x passed to ref_transaction_update()", flags); + + flags |= (new_oid ? REF_HAVE_NEW : 0) | (old_oid ? REF_HAVE_OLD : 0); + + ref_transaction_add_update(transaction, refname, flags, + new_oid, old_oid, msg); + return 0; +} + +int ref_transaction_create(struct ref_transaction *transaction, + const char *refname, + const struct object_id *new_oid, + unsigned int flags, const char *msg, + struct strbuf *err) +{ + if (!new_oid || is_null_oid(new_oid)) + BUG("create called without valid new_oid"); + return ref_transaction_update(transaction, refname, new_oid, + &null_oid, flags, msg, err); +} + +int ref_transaction_delete(struct ref_transaction *transaction, + const char *refname, + const struct object_id *old_oid, + unsigned int flags, const char *msg, + struct strbuf *err) +{ + if (old_oid && is_null_oid(old_oid)) + BUG("delete called with old_oid set to zeros"); + return ref_transaction_update(transaction, refname, + &null_oid, old_oid, + flags, msg, err); +} + +int ref_transaction_verify(struct ref_transaction *transaction, + const char *refname, + const struct object_id *old_oid, + unsigned int flags, + struct strbuf *err) +{ + if (!old_oid) + BUG("verify called with old_oid set to NULL"); + return ref_transaction_update(transaction, refname, + NULL, old_oid, + flags, NULL, err); +} + +int refs_update_ref(struct ref_store *refs, const char *msg, + const char *refname, const struct object_id *new_oid, + const struct object_id *old_oid, unsigned int flags, + enum action_on_err onerr) +{ + struct ref_transaction *t = NULL; + struct strbuf err = STRBUF_INIT; + int ret = 0; + + if (ref_type(refname) == REF_TYPE_PSEUDOREF) { + assert(refs == get_main_ref_store(the_repository)); + ret = write_pseudoref(refname, new_oid, old_oid, &err); + } else { + t = ref_store_transaction_begin(refs, &err); + if (!t || + ref_transaction_update(t, refname, new_oid, old_oid, + flags, msg, &err) || + ref_transaction_commit(t, &err)) { + ret = 1; + ref_transaction_free(t); + } + } + if (ret) { + const char *str = _("update_ref failed for ref '%s': %s"); + + switch (onerr) { + case UPDATE_REFS_MSG_ON_ERR: + error(str, refname, err.buf); + break; + case UPDATE_REFS_DIE_ON_ERR: + die(str, refname, err.buf); + break; + case UPDATE_REFS_QUIET_ON_ERR: + break; + } + strbuf_release(&err); + return 1; + } + strbuf_release(&err); + if (t) + ref_transaction_free(t); + return 0; +} + +int update_ref(const char *msg, const char *refname, + const struct object_id *new_oid, + const struct object_id *old_oid, + unsigned int flags, enum action_on_err onerr) +{ + return refs_update_ref(get_main_ref_store(the_repository), msg, refname, new_oid, + old_oid, flags, onerr); +} + +char *refs_shorten_unambiguous_ref(struct ref_store *refs, + const char *refname, int strict) +{ + int i; + static char **scanf_fmts; + static int nr_rules; + char *short_name; + struct strbuf resolved_buf = STRBUF_INIT; + + if (!nr_rules) { + /* + * Pre-generate scanf formats from ref_rev_parse_rules[]. + * Generate a format suitable for scanf from a + * ref_rev_parse_rules rule by interpolating "%s" at the + * location of the "%.*s". + */ + size_t total_len = 0; + size_t offset = 0; + + /* the rule list is NULL terminated, count them first */ + for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++) + /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */ + total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1; + + scanf_fmts = xmalloc(st_add(st_mult(sizeof(char *), nr_rules), total_len)); + + offset = 0; + for (i = 0; i < nr_rules; i++) { + assert(offset < total_len); + scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset; + offset += xsnprintf(scanf_fmts[i], total_len - offset, + ref_rev_parse_rules[i], 2, "%s") + 1; + } + } + + /* bail out if there are no rules */ + if (!nr_rules) + return xstrdup(refname); + + /* buffer for scanf result, at most refname must fit */ + short_name = xstrdup(refname); + + /* skip first rule, it will always match */ + for (i = nr_rules - 1; i > 0 ; --i) { + int j; + int rules_to_fail = i; + int short_name_len; + + if (1 != sscanf(refname, scanf_fmts[i], short_name)) + continue; + + short_name_len = strlen(short_name); + + /* + * in strict mode, all (except the matched one) rules + * must fail to resolve to a valid non-ambiguous ref + */ + if (strict) + rules_to_fail = nr_rules; + + /* + * check if the short name resolves to a valid ref, + * but use only rules prior to the matched one + */ + for (j = 0; j < rules_to_fail; j++) { + const char *rule = ref_rev_parse_rules[j]; + + /* skip matched rule */ + if (i == j) + continue; + + /* + * the short name is ambiguous, if it resolves + * (with this previous rule) to a valid ref + * read_ref() returns 0 on success + */ + strbuf_reset(&resolved_buf); + strbuf_addf(&resolved_buf, rule, + short_name_len, short_name); + if (refs_ref_exists(refs, resolved_buf.buf)) + break; + } + + /* + * short name is non-ambiguous if all previous rules + * haven't resolved to a valid ref + */ + if (j == rules_to_fail) { + strbuf_release(&resolved_buf); + return short_name; + } + } + + strbuf_release(&resolved_buf); + free(short_name); + return xstrdup(refname); +} + +char *shorten_unambiguous_ref(const char *refname, int strict) +{ + return refs_shorten_unambiguous_ref(get_main_ref_store(the_repository), + refname, strict); +} + +static struct string_list *hide_refs; + +int parse_hide_refs_config(const char *var, const char *value, const char *section) +{ + const char *key; + if (!strcmp("transfer.hiderefs", var) || + (!parse_config_key(var, section, NULL, NULL, &key) && + !strcmp(key, "hiderefs"))) { + char *ref; + int len; + + if (!value) + return config_error_nonbool(var); + ref = xstrdup(value); + len = strlen(ref); + while (len && ref[len - 1] == '/') + ref[--len] = '\0'; + if (!hide_refs) { + hide_refs = xcalloc(1, sizeof(*hide_refs)); + hide_refs->strdup_strings = 1; + } + string_list_append(hide_refs, ref); + } + return 0; +} + +int ref_is_hidden(const char *refname, const char *refname_full) +{ + int i; + + if (!hide_refs) + return 0; + for (i = hide_refs->nr - 1; i >= 0; i--) { + const char *match = hide_refs->items[i].string; + const char *subject; + int neg = 0; + const char *p; + + if (*match == '!') { + neg = 1; + match++; + } + + if (*match == '^') { + subject = refname_full; + match++; + } else { + subject = refname; + } + + /* refname can be NULL when namespaces are used. */ + if (subject && + skip_prefix(subject, match, &p) && + (!*p || *p == '/')) + return !neg; + } + return 0; +} + +const char *find_descendant_ref(const char *dirname, + const struct string_list *extras, + const struct string_list *skip) +{ + int pos; + + if (!extras) + return NULL; + + /* + * Look at the place where dirname would be inserted into + * extras. If there is an entry at that position that starts + * with dirname (remember, dirname includes the trailing + * slash) and is not in skip, then we have a conflict. + */ + for (pos = string_list_find_insert_index(extras, dirname, 0); + pos < extras->nr; pos++) { + const char *extra_refname = extras->items[pos].string; + + if (!starts_with(extra_refname, dirname)) + break; + + if (!skip || !string_list_has_string(skip, extra_refname)) + return extra_refname; + } + return NULL; +} + +int refs_rename_ref_available(struct ref_store *refs, + const char *old_refname, + const char *new_refname) +{ + struct string_list skip = STRING_LIST_INIT_NODUP; + struct strbuf err = STRBUF_INIT; + int ok; + + string_list_insert(&skip, old_refname); + ok = !refs_verify_refname_available(refs, new_refname, + NULL, &skip, &err); + if (!ok) + error("%s", err.buf); + + string_list_clear(&skip, 0); + strbuf_release(&err); + return ok; +} + +int refs_head_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data) +{ + struct object_id oid; + int flag; + + if (!refs_read_ref_full(refs, "HEAD", RESOLVE_REF_READING, + &oid, &flag)) + return fn("HEAD", &oid, flag, cb_data); + + return 0; +} + +int head_ref(each_ref_fn fn, void *cb_data) +{ + return refs_head_ref(get_main_ref_store(the_repository), fn, cb_data); +} + +struct ref_iterator *refs_ref_iterator_begin( + struct ref_store *refs, + const char *prefix, int trim, int flags) +{ + struct ref_iterator *iter; + + if (ref_paranoia < 0) + ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0); + if (ref_paranoia) + flags |= DO_FOR_EACH_INCLUDE_BROKEN; + + iter = refs->be->iterator_begin(refs, prefix, flags); + + /* + * `iterator_begin()` already takes care of prefix, but we + * might need to do some trimming: + */ + if (trim) + iter = prefix_ref_iterator_begin(iter, "", trim); + + /* Sanity check for subclasses: */ + if (!iter->ordered) + BUG("reference iterator is not ordered"); + + return iter; +} + +/* + * Call fn for each reference in the specified submodule for which the + * refname begins with prefix. If trim is non-zero, then trim that + * many characters off the beginning of each refname before passing + * the refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to + * include broken references in the iteration. If fn ever returns a + * non-zero value, stop the iteration and return that value; + * otherwise, return 0. + */ +static int do_for_each_repo_ref(struct repository *r, const char *prefix, + each_repo_ref_fn fn, int trim, int flags, + void *cb_data) +{ + struct ref_iterator *iter; + struct ref_store *refs = get_main_ref_store(r); + + if (!refs) + return 0; + + iter = refs_ref_iterator_begin(refs, prefix, trim, flags); + + return do_for_each_repo_ref_iterator(r, iter, fn, cb_data); +} + +struct do_for_each_ref_help { + each_ref_fn *fn; + void *cb_data; +}; + +static int do_for_each_ref_helper(struct repository *r, + const char *refname, + const struct object_id *oid, + int flags, + void *cb_data) +{ + struct do_for_each_ref_help *hp = cb_data; + + return hp->fn(refname, oid, flags, hp->cb_data); +} + +static int do_for_each_ref(struct ref_store *refs, const char *prefix, + each_ref_fn fn, int trim, int flags, void *cb_data) +{ + struct ref_iterator *iter; + struct do_for_each_ref_help hp = { fn, cb_data }; + + if (!refs) + return 0; + + iter = refs_ref_iterator_begin(refs, prefix, trim, flags); + + return do_for_each_repo_ref_iterator(the_repository, iter, + do_for_each_ref_helper, &hp); +} + +int refs_for_each_ref(struct ref_store *refs, each_ref_fn fn, void *cb_data) +{ + return do_for_each_ref(refs, "", fn, 0, 0, cb_data); +} + +int for_each_ref(each_ref_fn fn, void *cb_data) +{ + return refs_for_each_ref(get_main_ref_store(the_repository), fn, cb_data); +} + +int refs_for_each_ref_in(struct ref_store *refs, const char *prefix, + each_ref_fn fn, void *cb_data) +{ + return do_for_each_ref(refs, prefix, fn, strlen(prefix), 0, cb_data); +} + +int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data) +{ + return refs_for_each_ref_in(get_main_ref_store(the_repository), prefix, fn, cb_data); +} + +int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken) +{ + unsigned int flag = 0; + + if (broken) + flag = DO_FOR_EACH_INCLUDE_BROKEN; + return do_for_each_ref(get_main_ref_store(the_repository), + prefix, fn, 0, flag, cb_data); +} + +int refs_for_each_fullref_in(struct ref_store *refs, const char *prefix, + each_ref_fn fn, void *cb_data, + unsigned int broken) +{ + unsigned int flag = 0; + + if (broken) + flag = DO_FOR_EACH_INCLUDE_BROKEN; + return do_for_each_ref(refs, prefix, fn, 0, flag, cb_data); +} + +int for_each_replace_ref(struct repository *r, each_repo_ref_fn fn, void *cb_data) +{ + return do_for_each_repo_ref(r, git_replace_ref_base, fn, + strlen(git_replace_ref_base), + DO_FOR_EACH_INCLUDE_BROKEN, cb_data); +} + +int for_each_namespaced_ref(each_ref_fn fn, void *cb_data) +{ + struct strbuf buf = STRBUF_INIT; + int ret; + strbuf_addf(&buf, "%srefs/", get_git_namespace()); + ret = do_for_each_ref(get_main_ref_store(the_repository), + buf.buf, fn, 0, 0, cb_data); + strbuf_release(&buf); + return ret; +} + +int refs_for_each_rawref(struct ref_store *refs, each_ref_fn fn, void *cb_data) +{ + return do_for_each_ref(refs, "", fn, 0, + DO_FOR_EACH_INCLUDE_BROKEN, cb_data); +} + +int for_each_rawref(each_ref_fn fn, void *cb_data) +{ + return refs_for_each_rawref(get_main_ref_store(the_repository), fn, cb_data); +} + +int refs_read_raw_ref(struct ref_store *ref_store, + const char *refname, struct object_id *oid, + struct strbuf *referent, unsigned int *type) +{ + return ref_store->be->read_raw_ref(ref_store, refname, oid, referent, type); +} + +/* This function needs to return a meaningful errno on failure */ +const char *refs_resolve_ref_unsafe(struct ref_store *refs, + const char *refname, + int resolve_flags, + struct object_id *oid, int *flags) +{ + static struct strbuf sb_refname = STRBUF_INIT; + struct object_id unused_oid; + int unused_flags; + int symref_count; + + if (!oid) + oid = &unused_oid; + if (!flags) + flags = &unused_flags; + + *flags = 0; + + if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) { + if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) || + !refname_is_safe(refname)) { + errno = EINVAL; + return NULL; + } + + /* + * dwim_ref() uses REF_ISBROKEN to distinguish between + * missing refs and refs that were present but invalid, + * to complain about the latter to stderr. + * + * We don't know whether the ref exists, so don't set + * REF_ISBROKEN yet. + */ + *flags |= REF_BAD_NAME; + } + + for (symref_count = 0; symref_count < SYMREF_MAXDEPTH; symref_count++) { + unsigned int read_flags = 0; + + if (refs_read_raw_ref(refs, refname, + oid, &sb_refname, &read_flags)) { + *flags |= read_flags; + + /* In reading mode, refs must eventually resolve */ + if (resolve_flags & RESOLVE_REF_READING) + return NULL; + + /* + * Otherwise a missing ref is OK. But the files backend + * may show errors besides ENOENT if there are + * similarly-named refs. + */ + if (errno != ENOENT && + errno != EISDIR && + errno != ENOTDIR) + return NULL; + + oidclr(oid); + if (*flags & REF_BAD_NAME) + *flags |= REF_ISBROKEN; + return refname; + } + + *flags |= read_flags; + + if (!(read_flags & REF_ISSYMREF)) { + if (*flags & REF_BAD_NAME) { + oidclr(oid); + *flags |= REF_ISBROKEN; + } + return refname; + } + + refname = sb_refname.buf; + if (resolve_flags & RESOLVE_REF_NO_RECURSE) { + oidclr(oid); + return refname; + } + if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) { + if (!(resolve_flags & RESOLVE_REF_ALLOW_BAD_NAME) || + !refname_is_safe(refname)) { + errno = EINVAL; + return NULL; + } + + *flags |= REF_ISBROKEN | REF_BAD_NAME; + } + } + + errno = ELOOP; + return NULL; +} + +/* backend functions */ +int refs_init_db(struct strbuf *err) +{ + struct ref_store *refs = get_main_ref_store(the_repository); + + return refs->be->init_db(refs, err); +} + +const char *resolve_ref_unsafe(const char *refname, int resolve_flags, + struct object_id *oid, int *flags) +{ + return refs_resolve_ref_unsafe(get_main_ref_store(the_repository), refname, + resolve_flags, oid, flags); +} + +int resolve_gitlink_ref(const char *submodule, const char *refname, + struct object_id *oid) +{ + struct ref_store *refs; + int flags; + + refs = get_submodule_ref_store(submodule); + + if (!refs) + return -1; + + if (!refs_resolve_ref_unsafe(refs, refname, 0, oid, &flags) || + is_null_oid(oid)) + return -1; + return 0; +} + +struct ref_store_hash_entry +{ + struct hashmap_entry ent; /* must be the first member! */ + + struct ref_store *refs; + + /* NUL-terminated identifier of the ref store: */ + char name[FLEX_ARRAY]; +}; + +static int ref_store_hash_cmp(const void *unused_cmp_data, + const void *entry, const void *entry_or_key, + const void *keydata) +{ + const struct ref_store_hash_entry *e1 = entry, *e2 = entry_or_key; + const char *name = keydata ? keydata : e2->name; + + return strcmp(e1->name, name); +} + +static struct ref_store_hash_entry *alloc_ref_store_hash_entry( + const char *name, struct ref_store *refs) +{ + struct ref_store_hash_entry *entry; + + FLEX_ALLOC_STR(entry, name, name); + hashmap_entry_init(entry, strhash(name)); + entry->refs = refs; + return entry; +} + +/* A hashmap of ref_stores, stored by submodule name: */ +static struct hashmap submodule_ref_stores; + +/* A hashmap of ref_stores, stored by worktree id: */ +static struct hashmap worktree_ref_stores; + +/* + * Look up a ref store by name. If that ref_store hasn't been + * registered yet, return NULL. + */ +static struct ref_store *lookup_ref_store_map(struct hashmap *map, + const char *name) +{ + struct ref_store_hash_entry *entry; + + if (!map->tablesize) + /* It's initialized on demand in register_ref_store(). */ + return NULL; + + entry = hashmap_get_from_hash(map, strhash(name), name); + return entry ? entry->refs : NULL; +} + +/* + * Create, record, and return a ref_store instance for the specified + * gitdir. + */ +static struct ref_store *ref_store_init(const char *gitdir, + unsigned int flags) +{ + const char *be_name = "files"; + struct ref_storage_be *be = find_ref_storage_backend(be_name); + struct ref_store *refs; + + if (!be) + BUG("reference backend %s is unknown", be_name); + + refs = be->init(gitdir, flags); + return refs; +} + +struct ref_store *get_main_ref_store(struct repository *r) +{ + if (r->refs) + return r->refs; + + if (!r->gitdir) + BUG("attempting to get main_ref_store outside of repository"); + + r->refs = ref_store_init(r->gitdir, REF_STORE_ALL_CAPS); + return r->refs; +} + +/* + * Associate a ref store with a name. It is a fatal error to call this + * function twice for the same name. + */ +static void register_ref_store_map(struct hashmap *map, + const char *type, + struct ref_store *refs, + const char *name) +{ + if (!map->tablesize) + hashmap_init(map, ref_store_hash_cmp, NULL, 0); + + if (hashmap_put(map, alloc_ref_store_hash_entry(name, refs))) + BUG("%s ref_store '%s' initialized twice", type, name); +} + +struct ref_store *get_submodule_ref_store(const char *submodule) +{ + struct strbuf submodule_sb = STRBUF_INIT; + struct ref_store *refs; + char *to_free = NULL; + size_t len; + + if (!submodule) + return NULL; + + len = strlen(submodule); + while (len && is_dir_sep(submodule[len - 1])) + len--; + if (!len) + return NULL; + + if (submodule[len]) + /* We need to strip off one or more trailing slashes */ + submodule = to_free = xmemdupz(submodule, len); + + refs = lookup_ref_store_map(&submodule_ref_stores, submodule); + if (refs) + goto done; + + strbuf_addstr(&submodule_sb, submodule); + if (!is_nonbare_repository_dir(&submodule_sb)) + goto done; + + if (submodule_to_gitdir(&submodule_sb, submodule)) + goto done; + + /* assume that add_submodule_odb() has been called */ + refs = ref_store_init(submodule_sb.buf, + REF_STORE_READ | REF_STORE_ODB); + register_ref_store_map(&submodule_ref_stores, "submodule", + refs, submodule); + +done: + strbuf_release(&submodule_sb); + free(to_free); + + return refs; +} + +struct ref_store *get_worktree_ref_store(const struct worktree *wt) +{ + struct ref_store *refs; + const char *id; + + if (wt->is_current) + return get_main_ref_store(the_repository); + + id = wt->id ? wt->id : "/"; + refs = lookup_ref_store_map(&worktree_ref_stores, id); + if (refs) + return refs; + + if (wt->id) + refs = ref_store_init(git_common_path("worktrees/%s", wt->id), + REF_STORE_ALL_CAPS); + else + refs = ref_store_init(get_git_common_dir(), + REF_STORE_ALL_CAPS); + + if (refs) + register_ref_store_map(&worktree_ref_stores, "worktree", + refs, id); + return refs; +} + +void base_ref_store_init(struct ref_store *refs, + const struct ref_storage_be *be) +{ + refs->be = be; +} + +/* backend functions */ +int refs_pack_refs(struct ref_store *refs, unsigned int flags) +{ + return refs->be->pack_refs(refs, flags); +} + +int refs_peel_ref(struct ref_store *refs, const char *refname, + struct object_id *oid) +{ + int flag; + struct object_id base; + + if (current_ref_iter && current_ref_iter->refname == refname) { + struct object_id peeled; + + if (ref_iterator_peel(current_ref_iter, &peeled)) + return -1; + oidcpy(oid, &peeled); + return 0; + } + + if (refs_read_ref_full(refs, refname, + RESOLVE_REF_READING, &base, &flag)) + return -1; + + return peel_object(&base, oid); +} + +int peel_ref(const char *refname, struct object_id *oid) +{ + return refs_peel_ref(get_main_ref_store(the_repository), refname, oid); +} + +int refs_create_symref(struct ref_store *refs, + const char *ref_target, + const char *refs_heads_master, + const char *logmsg) +{ + return refs->be->create_symref(refs, ref_target, + refs_heads_master, + logmsg); +} + +int create_symref(const char *ref_target, const char *refs_heads_master, + const char *logmsg) +{ + return refs_create_symref(get_main_ref_store(the_repository), ref_target, + refs_heads_master, logmsg); +} + +int ref_update_reject_duplicates(struct string_list *refnames, + struct strbuf *err) +{ + size_t i, n = refnames->nr; + + assert(err); + + for (i = 1; i < n; i++) { + int cmp = strcmp(refnames->items[i - 1].string, + refnames->items[i].string); + + if (!cmp) { + strbuf_addf(err, + _("multiple updates for ref '%s' not allowed"), + refnames->items[i].string); + return 1; + } else if (cmp > 0) { + BUG("ref_update_reject_duplicates() received unsorted list"); + } + } + return 0; +} + +int ref_transaction_prepare(struct ref_transaction *transaction, + struct strbuf *err) +{ + struct ref_store *refs = transaction->ref_store; + + switch (transaction->state) { + case REF_TRANSACTION_OPEN: + /* Good. */ + break; + case REF_TRANSACTION_PREPARED: + BUG("prepare called twice on reference transaction"); + break; + case REF_TRANSACTION_CLOSED: + BUG("prepare called on a closed reference transaction"); + break; + default: + BUG("unexpected reference transaction state"); + break; + } + + if (getenv(GIT_QUARANTINE_ENVIRONMENT)) { + strbuf_addstr(err, + _("ref updates forbidden inside quarantine environment")); + return -1; + } + + return refs->be->transaction_prepare(refs, transaction, err); +} + +int ref_transaction_abort(struct ref_transaction *transaction, + struct strbuf *err) +{ + struct ref_store *refs = transaction->ref_store; + int ret = 0; + + switch (transaction->state) { + case REF_TRANSACTION_OPEN: + /* No need to abort explicitly. */ + break; + case REF_TRANSACTION_PREPARED: + ret = refs->be->transaction_abort(refs, transaction, err); + break; + case REF_TRANSACTION_CLOSED: + BUG("abort called on a closed reference transaction"); + break; + default: + BUG("unexpected reference transaction state"); + break; + } + + ref_transaction_free(transaction); + return ret; +} + +int ref_transaction_commit(struct ref_transaction *transaction, + struct strbuf *err) +{ + struct ref_store *refs = transaction->ref_store; + int ret; + + switch (transaction->state) { + case REF_TRANSACTION_OPEN: + /* Need to prepare first. */ + ret = ref_transaction_prepare(transaction, err); + if (ret) + return ret; + break; + case REF_TRANSACTION_PREPARED: + /* Fall through to finish. */ + break; + case REF_TRANSACTION_CLOSED: + BUG("commit called on a closed reference transaction"); + break; + default: + BUG("unexpected reference transaction state"); + break; + } + + return refs->be->transaction_finish(refs, transaction, err); +} + +int refs_verify_refname_available(struct ref_store *refs, + const char *refname, + const struct string_list *extras, + const struct string_list *skip, + struct strbuf *err) +{ + const char *slash; + const char *extra_refname; + struct strbuf dirname = STRBUF_INIT; + struct strbuf referent = STRBUF_INIT; + struct object_id oid; + unsigned int type; + struct ref_iterator *iter; + int ok; + int ret = -1; + + /* + * For the sake of comments in this function, suppose that + * refname is "refs/foo/bar". + */ + + assert(err); + + strbuf_grow(&dirname, strlen(refname) + 1); + for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) { + /* Expand dirname to the new prefix, not including the trailing slash: */ + strbuf_add(&dirname, refname + dirname.len, slash - refname - dirname.len); + + /* + * We are still at a leading dir of the refname (e.g., + * "refs/foo"; if there is a reference with that name, + * it is a conflict, *unless* it is in skip. + */ + if (skip && string_list_has_string(skip, dirname.buf)) + continue; + + if (!refs_read_raw_ref(refs, dirname.buf, &oid, &referent, &type)) { + strbuf_addf(err, _("'%s' exists; cannot create '%s'"), + dirname.buf, refname); + goto cleanup; + } + + if (extras && string_list_has_string(extras, dirname.buf)) { + strbuf_addf(err, _("cannot process '%s' and '%s' at the same time"), + refname, dirname.buf); + goto cleanup; + } + } + + /* + * We are at the leaf of our refname (e.g., "refs/foo/bar"). + * There is no point in searching for a reference with that + * name, because a refname isn't considered to conflict with + * itself. But we still need to check for references whose + * names are in the "refs/foo/bar/" namespace, because they + * *do* conflict. + */ + strbuf_addstr(&dirname, refname + dirname.len); + strbuf_addch(&dirname, '/'); + + iter = refs_ref_iterator_begin(refs, dirname.buf, 0, + DO_FOR_EACH_INCLUDE_BROKEN); + while ((ok = ref_iterator_advance(iter)) == ITER_OK) { + if (skip && + string_list_has_string(skip, iter->refname)) + continue; + + strbuf_addf(err, _("'%s' exists; cannot create '%s'"), + iter->refname, refname); + ref_iterator_abort(iter); + goto cleanup; + } + + if (ok != ITER_DONE) + BUG("error while iterating over references"); + + extra_refname = find_descendant_ref(dirname.buf, extras, skip); + if (extra_refname) + strbuf_addf(err, _("cannot process '%s' and '%s' at the same time"), + refname, extra_refname); + else + ret = 0; + +cleanup: + strbuf_release(&referent); + strbuf_release(&dirname); + return ret; +} + +int refs_for_each_reflog(struct ref_store *refs, each_ref_fn fn, void *cb_data) +{ + struct ref_iterator *iter; + struct do_for_each_ref_help hp = { fn, cb_data }; + + iter = refs->be->reflog_iterator_begin(refs); + + return do_for_each_repo_ref_iterator(the_repository, iter, + do_for_each_ref_helper, &hp); +} + +int for_each_reflog(each_ref_fn fn, void *cb_data) +{ + return refs_for_each_reflog(get_main_ref_store(the_repository), fn, cb_data); +} + +int refs_for_each_reflog_ent_reverse(struct ref_store *refs, + const char *refname, + each_reflog_ent_fn fn, + void *cb_data) +{ + return refs->be->for_each_reflog_ent_reverse(refs, refname, + fn, cb_data); +} + +int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, + void *cb_data) +{ + return refs_for_each_reflog_ent_reverse(get_main_ref_store(the_repository), + refname, fn, cb_data); +} + +int refs_for_each_reflog_ent(struct ref_store *refs, const char *refname, + each_reflog_ent_fn fn, void *cb_data) +{ + return refs->be->for_each_reflog_ent(refs, refname, fn, cb_data); +} + +int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, + void *cb_data) +{ + return refs_for_each_reflog_ent(get_main_ref_store(the_repository), refname, + fn, cb_data); +} + +int refs_reflog_exists(struct ref_store *refs, const char *refname) +{ + return refs->be->reflog_exists(refs, refname); +} + +int reflog_exists(const char *refname) +{ + return refs_reflog_exists(get_main_ref_store(the_repository), refname); +} + +int refs_create_reflog(struct ref_store *refs, const char *refname, + int force_create, struct strbuf *err) +{ + return refs->be->create_reflog(refs, refname, force_create, err); +} + +int safe_create_reflog(const char *refname, int force_create, + struct strbuf *err) +{ + return refs_create_reflog(get_main_ref_store(the_repository), refname, + force_create, err); +} + +int refs_delete_reflog(struct ref_store *refs, const char *refname) +{ + return refs->be->delete_reflog(refs, refname); +} + +int delete_reflog(const char *refname) +{ + return refs_delete_reflog(get_main_ref_store(the_repository), refname); +} + +int refs_reflog_expire(struct ref_store *refs, + const char *refname, const struct object_id *oid, + unsigned int flags, + reflog_expiry_prepare_fn prepare_fn, + reflog_expiry_should_prune_fn should_prune_fn, + reflog_expiry_cleanup_fn cleanup_fn, + void *policy_cb_data) +{ + return refs->be->reflog_expire(refs, refname, oid, flags, + prepare_fn, should_prune_fn, + cleanup_fn, policy_cb_data); +} + +int reflog_expire(const char *refname, const struct object_id *oid, + unsigned int flags, + reflog_expiry_prepare_fn prepare_fn, + reflog_expiry_should_prune_fn should_prune_fn, + reflog_expiry_cleanup_fn cleanup_fn, + void *policy_cb_data) +{ + return refs_reflog_expire(get_main_ref_store(the_repository), + refname, oid, flags, + prepare_fn, should_prune_fn, + cleanup_fn, policy_cb_data); +} + +int initial_ref_transaction_commit(struct ref_transaction *transaction, + struct strbuf *err) +{ + struct ref_store *refs = transaction->ref_store; + + return refs->be->initial_transaction_commit(refs, transaction, err); +} + +int refs_delete_refs(struct ref_store *refs, const char *msg, + struct string_list *refnames, unsigned int flags) +{ + return refs->be->delete_refs(refs, msg, refnames, flags); +} + +int delete_refs(const char *msg, struct string_list *refnames, + unsigned int flags) +{ + return refs_delete_refs(get_main_ref_store(the_repository), msg, refnames, flags); +} + +int refs_rename_ref(struct ref_store *refs, const char *oldref, + const char *newref, const char *logmsg) +{ + return refs->be->rename_ref(refs, oldref, newref, logmsg); +} + +int rename_ref(const char *oldref, const char *newref, const char *logmsg) +{ + return refs_rename_ref(get_main_ref_store(the_repository), oldref, newref, logmsg); +} + +int refs_copy_existing_ref(struct ref_store *refs, const char *oldref, + const char *newref, const char *logmsg) +{ + return refs->be->copy_ref(refs, oldref, newref, logmsg); +} + +int copy_existing_ref(const char *oldref, const char *newref, const char *logmsg) +{ + return refs_copy_existing_ref(get_main_ref_store(the_repository), oldref, newref, logmsg); +} |