diff options
Diffstat (limited to 'refs.c')
| -rw-r--r-- | refs.c | 1084 |
1 files changed, 1084 insertions, 0 deletions
diff --git a/refs.c b/refs.c new file mode 100644 index 0000000000..e2d34b253e --- /dev/null +++ b/refs.c @@ -0,0 +1,1084 @@ +/* + * The backend-independent part of the reference module. + */ + +#include "cache.h" +#include "lockfile.h" +#include "refs.h" +#include "refs/refs-internal.h" +#include "object.h" +#include "tag.h" + +/* + * 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: + * + * - any path component of 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 + */ +static int check_refname_component(const char *refname, int *flags) +{ + const char *cp; + char last = '\0'; + + for (cp = refname; ; cp++) { + int ch = *cp & 255; + unsigned char disp = refname_disposition[ch]; + switch (disp) { + case 1: + goto out; + case 2: + if (last == '.') + return -1; /* Refname contains "..". */ + break; + case 3: + if (last == '@') + return -1; /* Refname contains "@{". */ + break; + case 4: + return -1; + case 5: + if (!(*flags & REFNAME_REFSPEC_PATTERN)) + return -1; /* refspec can't be a pattern */ + + /* + * 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] == '.') + return -1; /* Component starts with '.'. */ + if (cp - refname >= LOCK_SUFFIX_LEN && + !memcmp(cp - LOCK_SUFFIX_LEN, LOCK_SUFFIX, LOCK_SUFFIX_LEN)) + return -1; /* Refname ends with ".lock". */ + return cp - refname; +} + +int check_refname_format(const char *refname, int flags) +{ + int component_len, component_count = 0; + + if (!strcmp(refname, "@")) + /* Refname is a single character '@'. */ + return -1; + + while (1) { + /* We are at the start of a path component. */ + component_len = check_refname_component(refname, &flags); + 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] == '.') + return -1; /* Refname ends with '.'. */ + if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2) + return -1; /* Refname has only one component. */ + return 0; +} + +int refname_is_safe(const char *refname) +{ + if (starts_with(refname, "refs/")) { + char *buf; + int result; + + buf = xmalloc(strlen(refname) + 1); + /* + * Does the refname try to escape refs/? + * For example: refs/foo/../bar is safe but refs/foo/../../bar + * is not. + */ + result = !normalize_path_copy(buf, refname + strlen("refs/")); + free(buf); + return result; + } + while (*refname) { + if (!isupper(*refname) && *refname != '_') + return 0; + refname++; + } + return 1; +} + +char *resolve_refdup(const char *refname, int resolve_flags, + unsigned char *sha1, int *flags) +{ + return xstrdup_or_null(resolve_ref_unsafe(refname, resolve_flags, + sha1, flags)); +} + +/* The argument to filter_refs */ +struct ref_filter { + const char *pattern; + each_ref_fn *fn; + void *cb_data; +}; + +int read_ref_full(const char *refname, int resolve_flags, unsigned char *sha1, int *flags) +{ + if (resolve_ref_unsafe(refname, resolve_flags, sha1, flags)) + return 0; + return -1; +} + +int read_ref(const char *refname, unsigned char *sha1) +{ + return read_ref_full(refname, RESOLVE_REF_READING, sha1, NULL); +} + +int ref_exists(const char *refname) +{ + unsigned char sha1[20]; + return !!resolve_ref_unsafe(refname, RESOLVE_REF_READING, sha1, NULL); +} + +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, NULL)) + return 0; + return filter->fn(refname, oid, flags, filter->cb_data); +} + +enum peel_status peel_object(const unsigned char *name, unsigned char *sha1) +{ + struct object *o = lookup_unknown_object(name); + + if (o->type == OBJ_NONE) { + int type = sha1_object_info(name, NULL); + if (type < 0 || !object_as_type(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; + + hashcpy(sha1, o->oid.hash); + 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; + struct object_id junk; + + if (!(flags & REF_ISSYMREF)) + return 0; + + resolves_to = resolve_ref_unsafe(refname, 0, junk.hash, 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 for_each_tag_ref(each_ref_fn fn, void *cb_data) +{ + return for_each_ref_in("refs/tags/", fn, cb_data); +} + +int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data) +{ + return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data); +} + +int for_each_branch_ref(each_ref_fn fn, void *cb_data) +{ + return for_each_ref_in("refs/heads/", fn, cb_data); +} + +int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data) +{ + return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data); +} + +int for_each_remote_ref(each_ref_fn fn, void *cb_data) +{ + return for_each_ref_in("refs/remotes/", fn, cb_data); +} + +int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data) +{ + return for_each_ref_in_submodule(submodule, "refs/remotes/", 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.hash, &flag)) + ret = fn(buf.buf, &oid, flag, cb_data); + strbuf_release(&buf); + + return ret; +} + +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.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) +{ + return name + ( + starts_with(name, "refs/heads/") ? 11 : + starts_with(name, "refs/tags/") ? 10 : + starts_with(name, "refs/remotes/") ? 13 : + 0); +} + +static const char *ref_rev_parse_rules[] = { + "%.*s", + "refs/%.*s", + "refs/tags/%.*s", + "refs/heads/%.*s", + "refs/remotes/%.*s", + "refs/remotes/%.*s/HEAD", + NULL +}; + +int refname_match(const char *abbrev_name, const char *full_name) +{ + const char **p; + const int abbrev_name_len = strlen(abbrev_name); + + for (p = ref_rev_parse_rules; *p; p++) { + if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) { + return 1; + } + } + + return 0; +} + +/* + * *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(const char **string, int *len) +{ + struct strbuf buf = STRBUF_INIT; + int ret = interpret_branch_name(*string, *len, &buf); + + if (ret == *len) { + size_t size; + *string = strbuf_detach(&buf, &size); + *len = size; + return (char *)*string; + } + + return NULL; +} + +int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref) +{ + char *last_branch = substitute_branch_name(&str, &len); + const char **p, *r; + int refs_found = 0; + + *ref = NULL; + for (p = ref_rev_parse_rules; *p; p++) { + char fullref[PATH_MAX]; + unsigned char sha1_from_ref[20]; + unsigned char *this_result; + int flag; + + this_result = refs_found ? sha1_from_ref : sha1; + mksnpath(fullref, sizeof(fullref), *p, len, str); + r = resolve_ref_unsafe(fullref, 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, "HEAD")) { + warning("ignoring dangling symref %s.", fullref); + } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) { + warning("ignoring broken ref %s.", fullref); + } + } + free(last_branch); + return refs_found; +} + +int dwim_log(const char *str, int len, unsigned char *sha1, char **log) +{ + char *last_branch = substitute_branch_name(&str, &len); + const char **p; + int logs_found = 0; + + *log = NULL; + for (p = ref_rev_parse_rules; *p; p++) { + unsigned char hash[20]; + char path[PATH_MAX]; + const char *ref, *it; + + mksnpath(path, sizeof(path), *p, len, str); + ref = resolve_ref_unsafe(path, RESOLVE_REF_READING, + hash, NULL); + if (!ref) + continue; + if (reflog_exists(path)) + it = path; + else if (strcmp(ref, path) && reflog_exists(ref)) + it = ref; + else + continue; + if (!logs_found++) { + *log = xstrdup(it); + hashcpy(sha1, hash); + } + if (!warn_ambiguous_refs) + break; + } + free(last_branch); + return logs_found; +} + +static int is_per_worktree_ref(const char *refname) +{ + return !strcmp(refname, "HEAD") || + starts_with(refname, "refs/bisect/"); +} + +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; +} + +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; + return REF_TYPE_NORMAL; +} + +static int write_pseudoref(const char *pseudoref, const unsigned char *sha1, + const unsigned char *old_sha1, struct strbuf *err) +{ + const char *filename; + int fd; + static struct lock_file lock; + struct strbuf buf = STRBUF_INIT; + int ret = -1; + + strbuf_addf(&buf, "%s\n", sha1_to_hex(sha1)); + + filename = git_path("%s", pseudoref); + fd = hold_lock_file_for_update(&lock, filename, LOCK_DIE_ON_ERROR); + if (fd < 0) { + strbuf_addf(err, "Could not open '%s' for writing: %s", + filename, strerror(errno)); + return -1; + } + + if (old_sha1) { + unsigned char actual_old_sha1[20]; + + if (read_ref(pseudoref, actual_old_sha1)) + die("could not read ref '%s'", pseudoref); + if (hashcmp(actual_old_sha1, old_sha1)) { + strbuf_addf(err, "Unexpected sha1 when writing %s", pseudoref); + rollback_lock_file(&lock); + goto done; + } + } + + if (write_in_full(fd, buf.buf, buf.len) != buf.len) { + 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 unsigned char *old_sha1) +{ + static struct lock_file lock; + const char *filename; + + filename = git_path("%s", pseudoref); + + if (old_sha1 && !is_null_sha1(old_sha1)) { + int fd; + unsigned char actual_old_sha1[20]; + + fd = hold_lock_file_for_update(&lock, filename, + LOCK_DIE_ON_ERROR); + if (fd < 0) + die_errno(_("Could not open '%s' for writing"), filename); + if (read_ref(pseudoref, actual_old_sha1)) + die("could not read ref '%s'", pseudoref); + if (hashcmp(actual_old_sha1, old_sha1)) { + warning("Unexpected sha1 when deleting %s", pseudoref); + rollback_lock_file(&lock); + return -1; + } + + unlink(filename); + rollback_lock_file(&lock); + } else { + unlink(filename); + } + + return 0; +} + +int delete_ref(const char *refname, const unsigned char *old_sha1, + unsigned int flags) +{ + struct ref_transaction *transaction; + struct strbuf err = STRBUF_INIT; + + if (ref_type(refname) == REF_TYPE_PSEUDOREF) + return delete_pseudoref(refname, old_sha1); + + transaction = ref_transaction_begin(&err); + if (!transaction || + ref_transaction_delete(transaction, refname, old_sha1, + flags, NULL, &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 copy_reflog_msg(char *buf, const char *msg) +{ + char *cp = buf; + char c; + int wasspace = 1; + + *cp++ = '\t'; + while ((c = *msg++)) { + if (wasspace && isspace(c)) + continue; + wasspace = isspace(c); + if (wasspace) + c = ' '; + *cp++ = c; + } + while (buf < cp && isspace(cp[-1])) + cp--; + *cp++ = '\n'; + return cp - buf; +} + +int should_autocreate_reflog(const char *refname) +{ + if (!log_all_ref_updates) + return 0; + return starts_with(refname, "refs/heads/") || + starts_with(refname, "refs/remotes/") || + starts_with(refname, "refs/notes/") || + !strcmp(refname, "HEAD"); +} + +int is_branch(const char *refname) +{ + return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/"); +} + +struct read_ref_at_cb { + const char *refname; + unsigned long at_time; + int cnt; + int reccnt; + unsigned char *sha1; + int found_it; + + unsigned char osha1[20]; + unsigned char nsha1[20]; + int tz; + unsigned long date; + char **msg; + unsigned long *cutoff_time; + int *cutoff_tz; + int *cutoff_cnt; +}; + +static int read_ref_at_ent(unsigned char *osha1, unsigned char *nsha1, + const char *email, unsigned long 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]sha1 so they still + * hold the values for the previous record. + */ + if (!is_null_sha1(cb->osha1)) { + hashcpy(cb->sha1, nsha1); + if (hashcmp(cb->osha1, nsha1)) + 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) + hashcpy(cb->sha1, nsha1); + else if (hashcmp(nsha1, cb->sha1)) + warning("Log for ref %s unexpectedly ended on %s.", + cb->refname, show_date(cb->date, cb->tz, + DATE_MODE(RFC2822))); + hashcpy(cb->osha1, osha1); + hashcpy(cb->nsha1, nsha1); + cb->found_it = 1; + return 1; + } + hashcpy(cb->osha1, osha1); + hashcpy(cb->nsha1, nsha1); + if (cb->cnt > 0) + cb->cnt--; + return 0; +} + +static int read_ref_at_ent_oldest(unsigned char *osha1, unsigned char *nsha1, + const char *email, unsigned long 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; + hashcpy(cb->sha1, osha1); + if (is_null_sha1(cb->sha1)) + hashcpy(cb->sha1, nsha1); + /* We just want the first entry */ + return 1; +} + +int read_ref_at(const char *refname, unsigned int flags, unsigned long at_time, int cnt, + unsigned char *sha1, char **msg, + unsigned long *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.sha1 = sha1; + + for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb); + + if (!cb.reccnt) { + if (flags & GET_SHA1_QUIETLY) + exit(128); + else + die("Log for %s is empty.", refname); + } + if (cb.found_it) + return 0; + + for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb); + + return 1; +} + +struct ref_transaction *ref_transaction_begin(struct strbuf *err) +{ + assert(err); + + return xcalloc(1, sizeof(struct ref_transaction)); +} + +void ref_transaction_free(struct ref_transaction *transaction) +{ + int i; + + if (!transaction) + return; + + for (i = 0; i < transaction->nr; i++) { + free(transaction->updates[i]->msg); + free(transaction->updates[i]); + } + free(transaction->updates); + free(transaction); +} + +static struct ref_update *add_update(struct ref_transaction *transaction, + const char *refname) +{ + size_t len = strlen(refname) + 1; + struct ref_update *update = xcalloc(1, sizeof(*update) + len); + + memcpy((char *)update->refname, refname, len); /* includes NUL */ + ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc); + transaction->updates[transaction->nr++] = update; + return update; +} + +int ref_transaction_update(struct ref_transaction *transaction, + const char *refname, + const unsigned char *new_sha1, + const unsigned char *old_sha1, + unsigned int flags, const char *msg, + struct strbuf *err) +{ + struct ref_update *update; + + assert(err); + + if (transaction->state != REF_TRANSACTION_OPEN) + die("BUG: update called for transaction that is not open"); + + if (new_sha1 && !is_null_sha1(new_sha1) && + check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) { + strbuf_addf(err, "refusing to update ref with bad name %s", + refname); + return -1; + } + + update = add_update(transaction, refname); + if (new_sha1) { + hashcpy(update->new_sha1, new_sha1); + flags |= REF_HAVE_NEW; + } + if (old_sha1) { + hashcpy(update->old_sha1, old_sha1); + flags |= REF_HAVE_OLD; + } + update->flags = flags; + if (msg) + update->msg = xstrdup(msg); + return 0; +} + +int ref_transaction_create(struct ref_transaction *transaction, + const char *refname, + const unsigned char *new_sha1, + unsigned int flags, const char *msg, + struct strbuf *err) +{ + if (!new_sha1 || is_null_sha1(new_sha1)) + die("BUG: create called without valid new_sha1"); + return ref_transaction_update(transaction, refname, new_sha1, + null_sha1, flags, msg, err); +} + +int ref_transaction_delete(struct ref_transaction *transaction, + const char *refname, + const unsigned char *old_sha1, + unsigned int flags, const char *msg, + struct strbuf *err) +{ + if (old_sha1 && is_null_sha1(old_sha1)) + die("BUG: delete called with old_sha1 set to zeros"); + return ref_transaction_update(transaction, refname, + null_sha1, old_sha1, + flags, msg, err); +} + +int ref_transaction_verify(struct ref_transaction *transaction, + const char *refname, + const unsigned char *old_sha1, + unsigned int flags, + struct strbuf *err) +{ + if (!old_sha1) + die("BUG: verify called with old_sha1 set to NULL"); + return ref_transaction_update(transaction, refname, + NULL, old_sha1, + flags, NULL, err); +} + +int update_ref(const char *msg, const char *refname, + const unsigned char *new_sha1, const unsigned char *old_sha1, + 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) { + ret = write_pseudoref(refname, new_sha1, old_sha1, &err); + } else { + t = ref_transaction_begin(&err); + if (!t || + ref_transaction_update(t, refname, new_sha1, old_sha1, + 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; +} + +char *shorten_unambiguous_ref(const char *refname, int strict) +{ + int i; + static char **scanf_fmts; + static int nr_rules; + char *short_name; + + 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(nr_rules * sizeof(char *) + 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 += snprintf(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]; + char refname[PATH_MAX]; + + /* 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 + */ + mksnpath(refname, sizeof(refname), + rule, short_name_len, short_name); + if (ref_exists(refname)) + break; + } + + /* + * short name is non-ambiguous if all previous rules + * haven't resolved to a valid ref + */ + if (j == rules_to_fail) + return short_name; + } + + free(short_name); + return xstrdup(refname); +} + +static struct string_list *hide_refs; + +int parse_hide_refs_config(const char *var, const char *value, const char *section) +{ + if (!strcmp("transfer.hiderefs", var) || + /* NEEDSWORK: use parse_config_key() once both are merged */ + (starts_with(var, section) && var[strlen(section)] == '.' && + !strcmp(var + strlen(section), ".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; + int len; + + if (*match == '!') { + neg = 1; + match++; + } + + if (*match == '^') { + subject = refname_full; + match++; + } else { + subject = refname; + } + + /* refname can be NULL when namespaces are used. */ + if (!subject || !starts_with(subject, match)) + continue; + len = strlen(match); + if (!subject[len] || subject[len] == '/') + 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 rename_ref_available(const char *oldname, const char *newname) +{ + struct string_list skip = STRING_LIST_INIT_NODUP; + struct strbuf err = STRBUF_INIT; + int ret; + + string_list_insert(&skip, oldname); + ret = !verify_refname_available(newname, NULL, &skip, &err); + if (!ret) + error("%s", err.buf); + + string_list_clear(&skip, 0); + strbuf_release(&err); + return ret; +} |