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-rw-r--r--src/libgit2/revparse.c949
1 files changed, 949 insertions, 0 deletions
diff --git a/src/libgit2/revparse.c b/src/libgit2/revparse.c
new file mode 100644
index 000000000..9bc28e9fc
--- /dev/null
+++ b/src/libgit2/revparse.c
@@ -0,0 +1,949 @@
+/*
+ * Copyright (C) the libgit2 contributors. All rights reserved.
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+
+#include "common.h"
+
+#include "str.h"
+#include "tree.h"
+#include "refdb.h"
+#include "regexp.h"
+#include "date.h"
+
+#include "git2.h"
+
+static int maybe_sha_or_abbrev(git_object **out, git_repository *repo, const char *spec, size_t speclen)
+{
+ git_oid oid;
+
+ if (git_oid_fromstrn(&oid, spec, speclen) < 0)
+ return GIT_ENOTFOUND;
+
+ return git_object_lookup_prefix(out, repo, &oid, speclen, GIT_OBJECT_ANY);
+}
+
+static int maybe_sha(git_object **out, git_repository *repo, const char *spec)
+{
+ size_t speclen = strlen(spec);
+
+ if (speclen != GIT_OID_HEXSZ)
+ return GIT_ENOTFOUND;
+
+ return maybe_sha_or_abbrev(out, repo, spec, speclen);
+}
+
+static int maybe_abbrev(git_object **out, git_repository *repo, const char *spec)
+{
+ size_t speclen = strlen(spec);
+
+ return maybe_sha_or_abbrev(out, repo, spec, speclen);
+}
+
+static int build_regex(git_regexp *regex, const char *pattern)
+{
+ int error;
+
+ if (*pattern == '\0') {
+ git_error_set(GIT_ERROR_REGEX, "empty pattern");
+ return GIT_EINVALIDSPEC;
+ }
+
+ error = git_regexp_compile(regex, pattern, 0);
+ if (!error)
+ return 0;
+
+ git_regexp_dispose(regex);
+
+ return error;
+}
+
+static int maybe_describe(git_object**out, git_repository *repo, const char *spec)
+{
+ const char *substr;
+ int error;
+ git_regexp regex;
+
+ substr = strstr(spec, "-g");
+
+ if (substr == NULL)
+ return GIT_ENOTFOUND;
+
+ if (build_regex(&regex, ".+-[0-9]+-g[0-9a-fA-F]+") < 0)
+ return -1;
+
+ error = git_regexp_match(&regex, spec);
+ git_regexp_dispose(&regex);
+
+ if (error)
+ return GIT_ENOTFOUND;
+
+ return maybe_abbrev(out, repo, substr+2);
+}
+
+static int revparse_lookup_object(
+ git_object **object_out,
+ git_reference **reference_out,
+ git_repository *repo,
+ const char *spec)
+{
+ int error;
+ git_reference *ref;
+
+ if ((error = maybe_sha(object_out, repo, spec)) != GIT_ENOTFOUND)
+ return error;
+
+ error = git_reference_dwim(&ref, repo, spec);
+ if (!error) {
+
+ error = git_object_lookup(
+ object_out, repo, git_reference_target(ref), GIT_OBJECT_ANY);
+
+ if (!error)
+ *reference_out = ref;
+
+ return error;
+ }
+
+ if (error != GIT_ENOTFOUND)
+ return error;
+
+ if ((strlen(spec) < GIT_OID_HEXSZ) &&
+ ((error = maybe_abbrev(object_out, repo, spec)) != GIT_ENOTFOUND))
+ return error;
+
+ if ((error = maybe_describe(object_out, repo, spec)) != GIT_ENOTFOUND)
+ return error;
+
+ git_error_set(GIT_ERROR_REFERENCE, "revspec '%s' not found", spec);
+ return GIT_ENOTFOUND;
+}
+
+static int try_parse_numeric(int *n, const char *curly_braces_content)
+{
+ int32_t content;
+ const char *end_ptr;
+
+ if (git__strntol32(&content, curly_braces_content, strlen(curly_braces_content),
+ &end_ptr, 10) < 0)
+ return -1;
+
+ if (*end_ptr != '\0')
+ return -1;
+
+ *n = (int)content;
+ return 0;
+}
+
+static int retrieve_previously_checked_out_branch_or_revision(git_object **out, git_reference **base_ref, git_repository *repo, const char *identifier, size_t position)
+{
+ git_reference *ref = NULL;
+ git_reflog *reflog = NULL;
+ git_regexp preg;
+ int error = -1;
+ size_t i, numentries, cur;
+ const git_reflog_entry *entry;
+ const char *msg;
+ git_str buf = GIT_STR_INIT;
+
+ cur = position;
+
+ if (*identifier != '\0' || *base_ref != NULL)
+ return GIT_EINVALIDSPEC;
+
+ if (build_regex(&preg, "checkout: moving from (.*) to .*") < 0)
+ return -1;
+
+ if (git_reference_lookup(&ref, repo, GIT_HEAD_FILE) < 0)
+ goto cleanup;
+
+ if (git_reflog_read(&reflog, repo, GIT_HEAD_FILE) < 0)
+ goto cleanup;
+
+ numentries = git_reflog_entrycount(reflog);
+
+ for (i = 0; i < numentries; i++) {
+ git_regmatch regexmatches[2];
+
+ entry = git_reflog_entry_byindex(reflog, i);
+ msg = git_reflog_entry_message(entry);
+ if (!msg)
+ continue;
+
+ if (git_regexp_search(&preg, msg, 2, regexmatches) < 0)
+ continue;
+
+ cur--;
+
+ if (cur > 0)
+ continue;
+
+ if ((git_str_put(&buf, msg+regexmatches[1].start, regexmatches[1].end - regexmatches[1].start)) < 0)
+ goto cleanup;
+
+ if ((error = git_reference_dwim(base_ref, repo, git_str_cstr(&buf))) == 0)
+ goto cleanup;
+
+ if (error < 0 && error != GIT_ENOTFOUND)
+ goto cleanup;
+
+ error = maybe_abbrev(out, repo, git_str_cstr(&buf));
+
+ goto cleanup;
+ }
+
+ error = GIT_ENOTFOUND;
+
+cleanup:
+ git_reference_free(ref);
+ git_str_dispose(&buf);
+ git_regexp_dispose(&preg);
+ git_reflog_free(reflog);
+ return error;
+}
+
+static int retrieve_oid_from_reflog(git_oid *oid, git_reference *ref, size_t identifier)
+{
+ git_reflog *reflog;
+ size_t numentries;
+ const git_reflog_entry *entry = NULL;
+ bool search_by_pos = (identifier <= 100000000);
+
+ if (git_reflog_read(&reflog, git_reference_owner(ref), git_reference_name(ref)) < 0)
+ return -1;
+
+ numentries = git_reflog_entrycount(reflog);
+
+ if (search_by_pos) {
+ if (numentries < identifier + 1)
+ goto notfound;
+
+ entry = git_reflog_entry_byindex(reflog, identifier);
+ git_oid_cpy(oid, git_reflog_entry_id_new(entry));
+ } else {
+ size_t i;
+ git_time commit_time;
+
+ for (i = 0; i < numentries; i++) {
+ entry = git_reflog_entry_byindex(reflog, i);
+ commit_time = git_reflog_entry_committer(entry)->when;
+
+ if (commit_time.time > (git_time_t)identifier)
+ continue;
+
+ git_oid_cpy(oid, git_reflog_entry_id_new(entry));
+ break;
+ }
+
+ if (i == numentries) {
+ if (entry == NULL)
+ goto notfound;
+
+ /*
+ * TODO: emit a warning (log for 'branch' only goes back to ...)
+ */
+ git_oid_cpy(oid, git_reflog_entry_id_new(entry));
+ }
+ }
+
+ git_reflog_free(reflog);
+ return 0;
+
+notfound:
+ git_error_set(
+ GIT_ERROR_REFERENCE,
+ "reflog for '%s' has only %"PRIuZ" entries, asked for %"PRIuZ,
+ git_reference_name(ref), numentries, identifier);
+
+ git_reflog_free(reflog);
+ return GIT_ENOTFOUND;
+}
+
+static int retrieve_revobject_from_reflog(git_object **out, git_reference **base_ref, git_repository *repo, const char *identifier, size_t position)
+{
+ git_reference *ref;
+ git_oid oid;
+ int error = -1;
+
+ if (*base_ref == NULL) {
+ if ((error = git_reference_dwim(&ref, repo, identifier)) < 0)
+ return error;
+ } else {
+ ref = *base_ref;
+ *base_ref = NULL;
+ }
+
+ if (position == 0) {
+ error = git_object_lookup(out, repo, git_reference_target(ref), GIT_OBJECT_ANY);
+ goto cleanup;
+ }
+
+ if ((error = retrieve_oid_from_reflog(&oid, ref, position)) < 0)
+ goto cleanup;
+
+ error = git_object_lookup(out, repo, &oid, GIT_OBJECT_ANY);
+
+cleanup:
+ git_reference_free(ref);
+ return error;
+}
+
+static int retrieve_remote_tracking_reference(git_reference **base_ref, const char *identifier, git_repository *repo)
+{
+ git_reference *tracking, *ref;
+ int error = -1;
+
+ if (*base_ref == NULL) {
+ if ((error = git_reference_dwim(&ref, repo, identifier)) < 0)
+ return error;
+ } else {
+ ref = *base_ref;
+ *base_ref = NULL;
+ }
+
+ if (!git_reference_is_branch(ref)) {
+ error = GIT_EINVALIDSPEC;
+ goto cleanup;
+ }
+
+ if ((error = git_branch_upstream(&tracking, ref)) < 0)
+ goto cleanup;
+
+ *base_ref = tracking;
+
+cleanup:
+ git_reference_free(ref);
+ return error;
+}
+
+static int handle_at_syntax(git_object **out, git_reference **ref, const char *spec, size_t identifier_len, git_repository *repo, const char *curly_braces_content)
+{
+ bool is_numeric;
+ int parsed = 0, error = -1;
+ git_str identifier = GIT_STR_INIT;
+ git_time_t timestamp;
+
+ GIT_ASSERT(*out == NULL);
+
+ if (git_str_put(&identifier, spec, identifier_len) < 0)
+ return -1;
+
+ is_numeric = !try_parse_numeric(&parsed, curly_braces_content);
+
+ if (*curly_braces_content == '-' && (!is_numeric || parsed == 0)) {
+ error = GIT_EINVALIDSPEC;
+ goto cleanup;
+ }
+
+ if (is_numeric) {
+ if (parsed < 0)
+ error = retrieve_previously_checked_out_branch_or_revision(out, ref, repo, git_str_cstr(&identifier), -parsed);
+ else
+ error = retrieve_revobject_from_reflog(out, ref, repo, git_str_cstr(&identifier), parsed);
+
+ goto cleanup;
+ }
+
+ if (!strcmp(curly_braces_content, "u") || !strcmp(curly_braces_content, "upstream")) {
+ error = retrieve_remote_tracking_reference(ref, git_str_cstr(&identifier), repo);
+
+ goto cleanup;
+ }
+
+ if (git_date_parse(&timestamp, curly_braces_content) < 0) {
+ error = GIT_EINVALIDSPEC;
+ goto cleanup;
+ }
+
+ error = retrieve_revobject_from_reflog(out, ref, repo, git_str_cstr(&identifier), (size_t)timestamp);
+
+cleanup:
+ git_str_dispose(&identifier);
+ return error;
+}
+
+static git_object_t parse_obj_type(const char *str)
+{
+ if (!strcmp(str, "commit"))
+ return GIT_OBJECT_COMMIT;
+
+ if (!strcmp(str, "tree"))
+ return GIT_OBJECT_TREE;
+
+ if (!strcmp(str, "blob"))
+ return GIT_OBJECT_BLOB;
+
+ if (!strcmp(str, "tag"))
+ return GIT_OBJECT_TAG;
+
+ return GIT_OBJECT_INVALID;
+}
+
+static int dereference_to_non_tag(git_object **out, git_object *obj)
+{
+ if (git_object_type(obj) == GIT_OBJECT_TAG)
+ return git_tag_peel(out, (git_tag *)obj);
+
+ return git_object_dup(out, obj);
+}
+
+static int handle_caret_parent_syntax(git_object **out, git_object *obj, int n)
+{
+ git_object *temp_commit = NULL;
+ int error;
+
+ if ((error = git_object_peel(&temp_commit, obj, GIT_OBJECT_COMMIT)) < 0)
+ return (error == GIT_EAMBIGUOUS || error == GIT_ENOTFOUND) ?
+ GIT_EINVALIDSPEC : error;
+
+ if (n == 0) {
+ *out = temp_commit;
+ return 0;
+ }
+
+ error = git_commit_parent((git_commit **)out, (git_commit*)temp_commit, n - 1);
+
+ git_object_free(temp_commit);
+ return error;
+}
+
+static int handle_linear_syntax(git_object **out, git_object *obj, int n)
+{
+ git_object *temp_commit = NULL;
+ int error;
+
+ if ((error = git_object_peel(&temp_commit, obj, GIT_OBJECT_COMMIT)) < 0)
+ return (error == GIT_EAMBIGUOUS || error == GIT_ENOTFOUND) ?
+ GIT_EINVALIDSPEC : error;
+
+ error = git_commit_nth_gen_ancestor((git_commit **)out, (git_commit*)temp_commit, n);
+
+ git_object_free(temp_commit);
+ return error;
+}
+
+static int handle_colon_syntax(
+ git_object **out,
+ git_object *obj,
+ const char *path)
+{
+ git_object *tree;
+ int error = -1;
+ git_tree_entry *entry = NULL;
+
+ if ((error = git_object_peel(&tree, obj, GIT_OBJECT_TREE)) < 0)
+ return error == GIT_ENOTFOUND ? GIT_EINVALIDSPEC : error;
+
+ if (*path == '\0') {
+ *out = tree;
+ return 0;
+ }
+
+ /*
+ * TODO: Handle the relative path syntax
+ * (:./relative/path and :../relative/path)
+ */
+ if ((error = git_tree_entry_bypath(&entry, (git_tree *)tree, path)) < 0)
+ goto cleanup;
+
+ error = git_tree_entry_to_object(out, git_object_owner(tree), entry);
+
+cleanup:
+ git_tree_entry_free(entry);
+ git_object_free(tree);
+
+ return error;
+}
+
+static int walk_and_search(git_object **out, git_revwalk *walk, git_regexp *regex)
+{
+ int error;
+ git_oid oid;
+ git_object *obj;
+
+ while (!(error = git_revwalk_next(&oid, walk))) {
+
+ error = git_object_lookup(&obj, git_revwalk_repository(walk), &oid, GIT_OBJECT_COMMIT);
+ if ((error < 0) && (error != GIT_ENOTFOUND))
+ return -1;
+
+ if (!git_regexp_match(regex, git_commit_message((git_commit*)obj))) {
+ *out = obj;
+ return 0;
+ }
+
+ git_object_free(obj);
+ }
+
+ if (error < 0 && error == GIT_ITEROVER)
+ error = GIT_ENOTFOUND;
+
+ return error;
+}
+
+static int handle_grep_syntax(git_object **out, git_repository *repo, const git_oid *spec_oid, const char *pattern)
+{
+ git_regexp preg;
+ git_revwalk *walk = NULL;
+ int error;
+
+ if ((error = build_regex(&preg, pattern)) < 0)
+ return error;
+
+ if ((error = git_revwalk_new(&walk, repo)) < 0)
+ goto cleanup;
+
+ git_revwalk_sorting(walk, GIT_SORT_TIME);
+
+ if (spec_oid == NULL) {
+ if ((error = git_revwalk_push_glob(walk, "refs/*")) < 0)
+ goto cleanup;
+ } else if ((error = git_revwalk_push(walk, spec_oid)) < 0)
+ goto cleanup;
+
+ error = walk_and_search(out, walk, &preg);
+
+cleanup:
+ git_regexp_dispose(&preg);
+ git_revwalk_free(walk);
+
+ return error;
+}
+
+static int handle_caret_curly_syntax(git_object **out, git_object *obj, const char *curly_braces_content)
+{
+ git_object_t expected_type;
+
+ if (*curly_braces_content == '\0')
+ return dereference_to_non_tag(out, obj);
+
+ if (*curly_braces_content == '/')
+ return handle_grep_syntax(out, git_object_owner(obj), git_object_id(obj), curly_braces_content + 1);
+
+ expected_type = parse_obj_type(curly_braces_content);
+
+ if (expected_type == GIT_OBJECT_INVALID)
+ return GIT_EINVALIDSPEC;
+
+ return git_object_peel(out, obj, expected_type);
+}
+
+static int extract_curly_braces_content(git_str *buf, const char *spec, size_t *pos)
+{
+ git_str_clear(buf);
+
+ GIT_ASSERT_ARG(spec[*pos] == '^' || spec[*pos] == '@');
+
+ (*pos)++;
+
+ if (spec[*pos] == '\0' || spec[*pos] != '{')
+ return GIT_EINVALIDSPEC;
+
+ (*pos)++;
+
+ while (spec[*pos] != '}') {
+ if (spec[*pos] == '\0')
+ return GIT_EINVALIDSPEC;
+
+ if (git_str_putc(buf, spec[(*pos)++]) < 0)
+ return -1;
+ }
+
+ (*pos)++;
+
+ return 0;
+}
+
+static int extract_path(git_str *buf, const char *spec, size_t *pos)
+{
+ git_str_clear(buf);
+
+ GIT_ASSERT_ARG(spec[*pos] == ':');
+
+ (*pos)++;
+
+ if (git_str_puts(buf, spec + *pos) < 0)
+ return -1;
+
+ *pos += git_str_len(buf);
+
+ return 0;
+}
+
+static int extract_how_many(int *n, const char *spec, size_t *pos)
+{
+ const char *end_ptr;
+ int parsed, accumulated;
+ char kind = spec[*pos];
+
+ GIT_ASSERT_ARG(spec[*pos] == '^' || spec[*pos] == '~');
+
+ accumulated = 0;
+
+ do {
+ do {
+ (*pos)++;
+ accumulated++;
+ } while (spec[(*pos)] == kind && kind == '~');
+
+ if (git__isdigit(spec[*pos])) {
+ if (git__strntol32(&parsed, spec + *pos, strlen(spec + *pos), &end_ptr, 10) < 0)
+ return GIT_EINVALIDSPEC;
+
+ accumulated += (parsed - 1);
+ *pos = end_ptr - spec;
+ }
+
+ } while (spec[(*pos)] == kind && kind == '~');
+
+ *n = accumulated;
+
+ return 0;
+}
+
+static int object_from_reference(git_object **object, git_reference *reference)
+{
+ git_reference *resolved = NULL;
+ int error;
+
+ if (git_reference_resolve(&resolved, reference) < 0)
+ return -1;
+
+ error = git_object_lookup(object, reference->db->repo, git_reference_target(resolved), GIT_OBJECT_ANY);
+ git_reference_free(resolved);
+
+ return error;
+}
+
+static int ensure_base_rev_loaded(git_object **object, git_reference **reference, const char *spec, size_t identifier_len, git_repository *repo, bool allow_empty_identifier)
+{
+ int error;
+ git_str identifier = GIT_STR_INIT;
+
+ if (*object != NULL)
+ return 0;
+
+ if (*reference != NULL)
+ return object_from_reference(object, *reference);
+
+ if (!allow_empty_identifier && identifier_len == 0)
+ return GIT_EINVALIDSPEC;
+
+ if (git_str_put(&identifier, spec, identifier_len) < 0)
+ return -1;
+
+ error = revparse_lookup_object(object, reference, repo, git_str_cstr(&identifier));
+ git_str_dispose(&identifier);
+
+ return error;
+}
+
+static int ensure_base_rev_is_not_known_yet(git_object *object)
+{
+ if (object == NULL)
+ return 0;
+
+ return GIT_EINVALIDSPEC;
+}
+
+static bool any_left_hand_identifier(git_object *object, git_reference *reference, size_t identifier_len)
+{
+ if (object != NULL)
+ return true;
+
+ if (reference != NULL)
+ return true;
+
+ if (identifier_len > 0)
+ return true;
+
+ return false;
+}
+
+static int ensure_left_hand_identifier_is_not_known_yet(git_object *object, git_reference *reference)
+{
+ if (!ensure_base_rev_is_not_known_yet(object) && reference == NULL)
+ return 0;
+
+ return GIT_EINVALIDSPEC;
+}
+
+static int revparse(
+ git_object **object_out,
+ git_reference **reference_out,
+ size_t *identifier_len_out,
+ git_repository *repo,
+ const char *spec)
+{
+ size_t pos = 0, identifier_len = 0;
+ int error = -1, n;
+ git_str buf = GIT_STR_INIT;
+
+ git_reference *reference = NULL;
+ git_object *base_rev = NULL;
+
+ bool should_return_reference = true;
+
+ GIT_ASSERT_ARG(object_out);
+ GIT_ASSERT_ARG(reference_out);
+ GIT_ASSERT_ARG(repo);
+ GIT_ASSERT_ARG(spec);
+
+ *object_out = NULL;
+ *reference_out = NULL;
+
+ while (spec[pos]) {
+ switch (spec[pos]) {
+ case '^':
+ should_return_reference = false;
+
+ if ((error = ensure_base_rev_loaded(&base_rev, &reference, spec, identifier_len, repo, false)) < 0)
+ goto cleanup;
+
+ if (spec[pos+1] == '{') {
+ git_object *temp_object = NULL;
+
+ if ((error = extract_curly_braces_content(&buf, spec, &pos)) < 0)
+ goto cleanup;
+
+ if ((error = handle_caret_curly_syntax(&temp_object, base_rev, git_str_cstr(&buf))) < 0)
+ goto cleanup;
+
+ git_object_free(base_rev);
+ base_rev = temp_object;
+ } else {
+ git_object *temp_object = NULL;
+
+ if ((error = extract_how_many(&n, spec, &pos)) < 0)
+ goto cleanup;
+
+ if ((error = handle_caret_parent_syntax(&temp_object, base_rev, n)) < 0)
+ goto cleanup;
+
+ git_object_free(base_rev);
+ base_rev = temp_object;
+ }
+ break;
+
+ case '~':
+ {
+ git_object *temp_object = NULL;
+
+ should_return_reference = false;
+
+ if ((error = extract_how_many(&n, spec, &pos)) < 0)
+ goto cleanup;
+
+ if ((error = ensure_base_rev_loaded(&base_rev, &reference, spec, identifier_len, repo, false)) < 0)
+ goto cleanup;
+
+ if ((error = handle_linear_syntax(&temp_object, base_rev, n)) < 0)
+ goto cleanup;
+
+ git_object_free(base_rev);
+ base_rev = temp_object;
+ break;
+ }
+
+ case ':':
+ {
+ git_object *temp_object = NULL;
+
+ should_return_reference = false;
+
+ if ((error = extract_path(&buf, spec, &pos)) < 0)
+ goto cleanup;
+
+ if (any_left_hand_identifier(base_rev, reference, identifier_len)) {
+ if ((error = ensure_base_rev_loaded(&base_rev, &reference, spec, identifier_len, repo, true)) < 0)
+ goto cleanup;
+
+ if ((error = handle_colon_syntax(&temp_object, base_rev, git_str_cstr(&buf))) < 0)
+ goto cleanup;
+ } else {
+ if (*git_str_cstr(&buf) == '/') {
+ if ((error = handle_grep_syntax(&temp_object, repo, NULL, git_str_cstr(&buf) + 1)) < 0)
+ goto cleanup;
+ } else {
+
+ /*
+ * TODO: support merge-stage path lookup (":2:Makefile")
+ * and plain index blob lookup (:i-am/a/blob)
+ */
+ git_error_set(GIT_ERROR_INVALID, "unimplemented");
+ error = GIT_ERROR;
+ goto cleanup;
+ }
+ }
+
+ git_object_free(base_rev);
+ base_rev = temp_object;
+ break;
+ }
+
+ case '@':
+ if (spec[pos+1] == '{') {
+ git_object *temp_object = NULL;
+
+ if ((error = extract_curly_braces_content(&buf, spec, &pos)) < 0)
+ goto cleanup;
+
+ if ((error = ensure_base_rev_is_not_known_yet(base_rev)) < 0)
+ goto cleanup;
+
+ if ((error = handle_at_syntax(&temp_object, &reference, spec, identifier_len, repo, git_str_cstr(&buf))) < 0)
+ goto cleanup;
+
+ if (temp_object != NULL)
+ base_rev = temp_object;
+ break;
+ } else if (spec[pos+1] == '\0') {
+ spec = "HEAD";
+ break;
+ }
+ /* fall through */
+
+ default:
+ if ((error = ensure_left_hand_identifier_is_not_known_yet(base_rev, reference)) < 0)
+ goto cleanup;
+
+ pos++;
+ identifier_len++;
+ }
+ }
+
+ if ((error = ensure_base_rev_loaded(&base_rev, &reference, spec, identifier_len, repo, false)) < 0)
+ goto cleanup;
+
+ if (!should_return_reference) {
+ git_reference_free(reference);
+ reference = NULL;
+ }
+
+ *object_out = base_rev;
+ *reference_out = reference;
+ *identifier_len_out = identifier_len;
+ error = 0;
+
+cleanup:
+ if (error) {
+ if (error == GIT_EINVALIDSPEC)
+ git_error_set(GIT_ERROR_INVALID,
+ "failed to parse revision specifier - Invalid pattern '%s'", spec);
+
+ git_object_free(base_rev);
+ git_reference_free(reference);
+ }
+
+ git_str_dispose(&buf);
+ return error;
+}
+
+int git_revparse_ext(
+ git_object **object_out,
+ git_reference **reference_out,
+ git_repository *repo,
+ const char *spec)
+{
+ int error;
+ size_t identifier_len;
+ git_object *obj = NULL;
+ git_reference *ref = NULL;
+
+ if ((error = revparse(&obj, &ref, &identifier_len, repo, spec)) < 0)
+ goto cleanup;
+
+ *object_out = obj;
+ *reference_out = ref;
+ GIT_UNUSED(identifier_len);
+
+ return 0;
+
+cleanup:
+ git_object_free(obj);
+ git_reference_free(ref);
+ return error;
+}
+
+int git_revparse_single(git_object **out, git_repository *repo, const char *spec)
+{
+ int error;
+ git_object *obj = NULL;
+ git_reference *ref = NULL;
+
+ *out = NULL;
+
+ if ((error = git_revparse_ext(&obj, &ref, repo, spec)) < 0)
+ goto cleanup;
+
+ git_reference_free(ref);
+
+ *out = obj;
+
+ return 0;
+
+cleanup:
+ git_object_free(obj);
+ git_reference_free(ref);
+ return error;
+}
+
+int git_revparse(
+ git_revspec *revspec,
+ git_repository *repo,
+ const char *spec)
+{
+ const char *dotdot;
+ int error = 0;
+
+ GIT_ASSERT_ARG(revspec);
+ GIT_ASSERT_ARG(repo);
+ GIT_ASSERT_ARG(spec);
+
+ memset(revspec, 0x0, sizeof(*revspec));
+
+ if ((dotdot = strstr(spec, "..")) != NULL) {
+ char *lstr;
+ const char *rstr;
+ revspec->flags = GIT_REVSPEC_RANGE;
+
+ /*
+ * Following git.git, don't allow '..' because it makes command line
+ * arguments which can be either paths or revisions ambiguous when the
+ * path is almost certainly intended. The empty range '...' is still
+ * allowed.
+ */
+ if (!git__strcmp(spec, "..")) {
+ git_error_set(GIT_ERROR_INVALID, "Invalid pattern '..'");
+ return GIT_EINVALIDSPEC;
+ }
+
+ lstr = git__substrdup(spec, dotdot - spec);
+ rstr = dotdot + 2;
+ if (dotdot[2] == '.') {
+ revspec->flags |= GIT_REVSPEC_MERGE_BASE;
+ rstr++;
+ }
+
+ error = git_revparse_single(
+ &revspec->from,
+ repo,
+ *lstr == '\0' ? "HEAD" : lstr);
+
+ if (!error) {
+ error = git_revparse_single(
+ &revspec->to,
+ repo,
+ *rstr == '\0' ? "HEAD" : rstr);
+ }
+
+ git__free((void*)lstr);
+ } else {
+ revspec->flags = GIT_REVSPEC_SINGLE;
+ error = git_revparse_single(&revspec->from, repo, spec);
+ }
+
+ return error;
+}