diff options
Diffstat (limited to 'third_party/git/commit.c')
| -rw-r--r-- | third_party/git/commit.c | 1582 |
1 files changed, 1582 insertions, 0 deletions
diff --git a/third_party/git/commit.c b/third_party/git/commit.c new file mode 100644 index 000000000000..a98de16e3d57 --- /dev/null +++ b/third_party/git/commit.c @@ -0,0 +1,1582 @@ +#include "cache.h" +#include "tag.h" +#include "commit.h" +#include "commit-graph.h" +#include "repository.h" +#include "object-store.h" +#include "pkt-line.h" +#include "utf8.h" +#include "diff.h" +#include "revision.h" +#include "notes.h" +#include "alloc.h" +#include "gpg-interface.h" +#include "mergesort.h" +#include "commit-slab.h" +#include "prio-queue.h" +#include "sha1-lookup.h" +#include "wt-status.h" +#include "advice.h" +#include "refs.h" +#include "commit-reach.h" + +static struct commit_extra_header *read_commit_extra_header_lines(const char *buf, size_t len, const char **); + +int save_commit_buffer = 1; + +const char *commit_type = "commit"; + +struct commit *lookup_commit_reference_gently(struct repository *r, + const struct object_id *oid, int quiet) +{ + struct object *obj = deref_tag(r, + parse_object(r, oid), + NULL, 0); + + if (!obj) + return NULL; + return object_as_type(r, obj, OBJ_COMMIT, quiet); +} + +struct commit *lookup_commit_reference(struct repository *r, const struct object_id *oid) +{ + return lookup_commit_reference_gently(r, oid, 0); +} + +struct commit *lookup_commit_or_die(const struct object_id *oid, const char *ref_name) +{ + struct commit *c = lookup_commit_reference(the_repository, oid); + if (!c) + die(_("could not parse %s"), ref_name); + if (!oideq(oid, &c->object.oid)) { + warning(_("%s %s is not a commit!"), + ref_name, oid_to_hex(oid)); + } + return c; +} + +struct commit *lookup_commit(struct repository *r, const struct object_id *oid) +{ + struct object *obj = lookup_object(r, oid); + if (!obj) + return create_object(r, oid, alloc_commit_node(r)); + return object_as_type(r, obj, OBJ_COMMIT, 0); +} + +struct commit *lookup_commit_reference_by_name(const char *name) +{ + struct object_id oid; + struct commit *commit; + + if (get_oid_committish(name, &oid)) + return NULL; + commit = lookup_commit_reference(the_repository, &oid); + if (parse_commit(commit)) + return NULL; + return commit; +} + +static timestamp_t parse_commit_date(const char *buf, const char *tail) +{ + const char *dateptr; + + if (buf + 6 >= tail) + return 0; + if (memcmp(buf, "author", 6)) + return 0; + while (buf < tail && *buf++ != '\n') + /* nada */; + if (buf + 9 >= tail) + return 0; + if (memcmp(buf, "committer", 9)) + return 0; + while (buf < tail && *buf++ != '>') + /* nada */; + if (buf >= tail) + return 0; + dateptr = buf; + while (buf < tail && *buf++ != '\n') + /* nada */; + if (buf >= tail) + return 0; + /* dateptr < buf && buf[-1] == '\n', so parsing will stop at buf-1 */ + return parse_timestamp(dateptr, NULL, 10); +} + +static const unsigned char *commit_graft_sha1_access(size_t index, void *table) +{ + struct commit_graft **commit_graft_table = table; + return commit_graft_table[index]->oid.hash; +} + +static int commit_graft_pos(struct repository *r, const unsigned char *sha1) +{ + return sha1_pos(sha1, r->parsed_objects->grafts, + r->parsed_objects->grafts_nr, + commit_graft_sha1_access); +} + +int register_commit_graft(struct repository *r, struct commit_graft *graft, + int ignore_dups) +{ + int pos = commit_graft_pos(r, graft->oid.hash); + + if (0 <= pos) { + if (ignore_dups) + free(graft); + else { + free(r->parsed_objects->grafts[pos]); + r->parsed_objects->grafts[pos] = graft; + } + return 1; + } + pos = -pos - 1; + ALLOC_GROW(r->parsed_objects->grafts, + r->parsed_objects->grafts_nr + 1, + r->parsed_objects->grafts_alloc); + r->parsed_objects->grafts_nr++; + if (pos < r->parsed_objects->grafts_nr) + memmove(r->parsed_objects->grafts + pos + 1, + r->parsed_objects->grafts + pos, + (r->parsed_objects->grafts_nr - pos - 1) * + sizeof(*r->parsed_objects->grafts)); + r->parsed_objects->grafts[pos] = graft; + return 0; +} + +struct commit_graft *read_graft_line(struct strbuf *line) +{ + /* The format is just "Commit Parent1 Parent2 ...\n" */ + int i, phase; + const char *tail = NULL; + struct commit_graft *graft = NULL; + struct object_id dummy_oid, *oid; + + strbuf_rtrim(line); + if (!line->len || line->buf[0] == '#') + return NULL; + /* + * phase 0 verifies line, counts hashes in line and allocates graft + * phase 1 fills graft + */ + for (phase = 0; phase < 2; phase++) { + oid = graft ? &graft->oid : &dummy_oid; + if (parse_oid_hex(line->buf, oid, &tail)) + goto bad_graft_data; + for (i = 0; *tail != '\0'; i++) { + oid = graft ? &graft->parent[i] : &dummy_oid; + if (!isspace(*tail++) || parse_oid_hex(tail, oid, &tail)) + goto bad_graft_data; + } + if (!graft) { + graft = xmalloc(st_add(sizeof(*graft), + st_mult(sizeof(struct object_id), i))); + graft->nr_parent = i; + } + } + return graft; + +bad_graft_data: + error("bad graft data: %s", line->buf); + assert(!graft); + return NULL; +} + +static int read_graft_file(struct repository *r, const char *graft_file) +{ + FILE *fp = fopen_or_warn(graft_file, "r"); + struct strbuf buf = STRBUF_INIT; + if (!fp) + return -1; + if (advice_graft_file_deprecated) + advise(_("Support for <GIT_DIR>/info/grafts is deprecated\n" + "and will be removed in a future Git version.\n" + "\n" + "Please use \"git replace --convert-graft-file\"\n" + "to convert the grafts into replace refs.\n" + "\n" + "Turn this message off by running\n" + "\"git config advice.graftFileDeprecated false\"")); + while (!strbuf_getwholeline(&buf, fp, '\n')) { + /* The format is just "Commit Parent1 Parent2 ...\n" */ + struct commit_graft *graft = read_graft_line(&buf); + if (!graft) + continue; + if (register_commit_graft(r, graft, 1)) + error("duplicate graft data: %s", buf.buf); + } + fclose(fp); + strbuf_release(&buf); + return 0; +} + +void prepare_commit_graft(struct repository *r) +{ + char *graft_file; + + if (r->parsed_objects->commit_graft_prepared) + return; + if (!startup_info->have_repository) + return; + + graft_file = get_graft_file(r); + read_graft_file(r, graft_file); + /* make sure shallows are read */ + is_repository_shallow(r); + r->parsed_objects->commit_graft_prepared = 1; +} + +struct commit_graft *lookup_commit_graft(struct repository *r, const struct object_id *oid) +{ + int pos; + prepare_commit_graft(r); + pos = commit_graft_pos(r, oid->hash); + if (pos < 0) + return NULL; + return r->parsed_objects->grafts[pos]; +} + +int for_each_commit_graft(each_commit_graft_fn fn, void *cb_data) +{ + int i, ret; + for (i = ret = 0; i < the_repository->parsed_objects->grafts_nr && !ret; i++) + ret = fn(the_repository->parsed_objects->grafts[i], cb_data); + return ret; +} + +int unregister_shallow(const struct object_id *oid) +{ + int pos = commit_graft_pos(the_repository, oid->hash); + if (pos < 0) + return -1; + if (pos + 1 < the_repository->parsed_objects->grafts_nr) + MOVE_ARRAY(the_repository->parsed_objects->grafts + pos, + the_repository->parsed_objects->grafts + pos + 1, + the_repository->parsed_objects->grafts_nr - pos - 1); + the_repository->parsed_objects->grafts_nr--; + return 0; +} + +struct commit_buffer { + void *buffer; + unsigned long size; +}; +define_commit_slab(buffer_slab, struct commit_buffer); + +struct buffer_slab *allocate_commit_buffer_slab(void) +{ + struct buffer_slab *bs = xmalloc(sizeof(*bs)); + init_buffer_slab(bs); + return bs; +} + +void free_commit_buffer_slab(struct buffer_slab *bs) +{ + clear_buffer_slab(bs); + free(bs); +} + +void set_commit_buffer(struct repository *r, struct commit *commit, void *buffer, unsigned long size) +{ + struct commit_buffer *v = buffer_slab_at( + r->parsed_objects->buffer_slab, commit); + v->buffer = buffer; + v->size = size; +} + +const void *get_cached_commit_buffer(struct repository *r, const struct commit *commit, unsigned long *sizep) +{ + struct commit_buffer *v = buffer_slab_peek( + r->parsed_objects->buffer_slab, commit); + if (!v) { + if (sizep) + *sizep = 0; + return NULL; + } + if (sizep) + *sizep = v->size; + return v->buffer; +} + +const void *repo_get_commit_buffer(struct repository *r, + const struct commit *commit, + unsigned long *sizep) +{ + const void *ret = get_cached_commit_buffer(r, commit, sizep); + if (!ret) { + enum object_type type; + unsigned long size; + ret = repo_read_object_file(r, &commit->object.oid, &type, &size); + if (!ret) + die("cannot read commit object %s", + oid_to_hex(&commit->object.oid)); + if (type != OBJ_COMMIT) + die("expected commit for %s, got %s", + oid_to_hex(&commit->object.oid), type_name(type)); + if (sizep) + *sizep = size; + } + return ret; +} + +void repo_unuse_commit_buffer(struct repository *r, + const struct commit *commit, + const void *buffer) +{ + struct commit_buffer *v = buffer_slab_peek( + r->parsed_objects->buffer_slab, commit); + if (!(v && v->buffer == buffer)) + free((void *)buffer); +} + +void free_commit_buffer(struct parsed_object_pool *pool, struct commit *commit) +{ + struct commit_buffer *v = buffer_slab_peek( + pool->buffer_slab, commit); + if (v) { + FREE_AND_NULL(v->buffer); + v->size = 0; + } +} + +static inline void set_commit_tree(struct commit *c, struct tree *t) +{ + c->maybe_tree = t; +} + +struct tree *repo_get_commit_tree(struct repository *r, + const struct commit *commit) +{ + if (commit->maybe_tree || !commit->object.parsed) + return commit->maybe_tree; + + if (commit->graph_pos != COMMIT_NOT_FROM_GRAPH) + return get_commit_tree_in_graph(r, commit); + + return NULL; +} + +struct object_id *get_commit_tree_oid(const struct commit *commit) +{ + return &get_commit_tree(commit)->object.oid; +} + +void release_commit_memory(struct parsed_object_pool *pool, struct commit *c) +{ + set_commit_tree(c, NULL); + c->index = 0; + free_commit_buffer(pool, c); + free_commit_list(c->parents); + + c->object.parsed = 0; +} + +const void *detach_commit_buffer(struct commit *commit, unsigned long *sizep) +{ + struct commit_buffer *v = buffer_slab_peek( + the_repository->parsed_objects->buffer_slab, commit); + void *ret; + + if (!v) { + if (sizep) + *sizep = 0; + return NULL; + } + ret = v->buffer; + if (sizep) + *sizep = v->size; + + v->buffer = NULL; + v->size = 0; + return ret; +} + +int parse_commit_buffer(struct repository *r, struct commit *item, const void *buffer, unsigned long size, int check_graph) +{ + const char *tail = buffer; + const char *bufptr = buffer; + struct object_id parent; + struct commit_list **pptr; + struct commit_graft *graft; + const int tree_entry_len = the_hash_algo->hexsz + 5; + const int parent_entry_len = the_hash_algo->hexsz + 7; + + if (item->object.parsed) + return 0; + item->object.parsed = 1; + tail += size; + if (tail <= bufptr + tree_entry_len + 1 || memcmp(bufptr, "tree ", 5) || + bufptr[tree_entry_len] != '\n') + return error("bogus commit object %s", oid_to_hex(&item->object.oid)); + if (get_oid_hex(bufptr + 5, &parent) < 0) + return error("bad tree pointer in commit %s", + oid_to_hex(&item->object.oid)); + set_commit_tree(item, lookup_tree(r, &parent)); + bufptr += tree_entry_len + 1; /* "tree " + "hex sha1" + "\n" */ + pptr = &item->parents; + + graft = lookup_commit_graft(r, &item->object.oid); + while (bufptr + parent_entry_len < tail && !memcmp(bufptr, "parent ", 7)) { + struct commit *new_parent; + + if (tail <= bufptr + parent_entry_len + 1 || + get_oid_hex(bufptr + 7, &parent) || + bufptr[parent_entry_len] != '\n') + return error("bad parents in commit %s", oid_to_hex(&item->object.oid)); + bufptr += parent_entry_len + 1; + /* + * The clone is shallow if nr_parent < 0, and we must + * not traverse its real parents even when we unhide them. + */ + if (graft && (graft->nr_parent < 0 || grafts_replace_parents)) + continue; + new_parent = lookup_commit(r, &parent); + if (new_parent) + pptr = &commit_list_insert(new_parent, pptr)->next; + } + if (graft) { + int i; + struct commit *new_parent; + for (i = 0; i < graft->nr_parent; i++) { + new_parent = lookup_commit(r, + &graft->parent[i]); + if (!new_parent) + continue; + pptr = &commit_list_insert(new_parent, pptr)->next; + } + } + item->date = parse_commit_date(bufptr, tail); + + if (check_graph) + load_commit_graph_info(r, item); + + return 0; +} + +int repo_parse_commit_internal(struct repository *r, + struct commit *item, + int quiet_on_missing, + int use_commit_graph) +{ + enum object_type type; + void *buffer; + unsigned long size; + int ret; + + if (!item) + return -1; + if (item->object.parsed) + return 0; + if (use_commit_graph && parse_commit_in_graph(r, item)) + return 0; + buffer = repo_read_object_file(r, &item->object.oid, &type, &size); + if (!buffer) + return quiet_on_missing ? -1 : + error("Could not read %s", + oid_to_hex(&item->object.oid)); + if (type != OBJ_COMMIT) { + free(buffer); + return error("Object %s not a commit", + oid_to_hex(&item->object.oid)); + } + + ret = parse_commit_buffer(r, item, buffer, size, 0); + if (save_commit_buffer && !ret) { + set_commit_buffer(r, item, buffer, size); + return 0; + } + free(buffer); + return ret; +} + +int repo_parse_commit_gently(struct repository *r, + struct commit *item, int quiet_on_missing) +{ + return repo_parse_commit_internal(r, item, quiet_on_missing, 1); +} + +void parse_commit_or_die(struct commit *item) +{ + if (parse_commit(item)) + die("unable to parse commit %s", + item ? oid_to_hex(&item->object.oid) : "(null)"); +} + +int find_commit_subject(const char *commit_buffer, const char **subject) +{ + const char *eol; + const char *p = commit_buffer; + + while (*p && (*p != '\n' || p[1] != '\n')) + p++; + if (*p) { + p = skip_blank_lines(p + 2); + eol = strchrnul(p, '\n'); + } else + eol = p; + + *subject = p; + + return eol - p; +} + +struct commit_list *commit_list_insert(struct commit *item, struct commit_list **list_p) +{ + struct commit_list *new_list = xmalloc(sizeof(struct commit_list)); + new_list->item = item; + new_list->next = *list_p; + *list_p = new_list; + return new_list; +} + +unsigned commit_list_count(const struct commit_list *l) +{ + unsigned c = 0; + for (; l; l = l->next ) + c++; + return c; +} + +struct commit_list *copy_commit_list(struct commit_list *list) +{ + struct commit_list *head = NULL; + struct commit_list **pp = &head; + while (list) { + pp = commit_list_append(list->item, pp); + list = list->next; + } + return head; +} + +void free_commit_list(struct commit_list *list) +{ + while (list) + pop_commit(&list); +} + +struct commit_list * commit_list_insert_by_date(struct commit *item, struct commit_list **list) +{ + struct commit_list **pp = list; + struct commit_list *p; + while ((p = *pp) != NULL) { + if (p->item->date < item->date) { + break; + } + pp = &p->next; + } + return commit_list_insert(item, pp); +} + +static int commit_list_compare_by_date(const void *a, const void *b) +{ + timestamp_t a_date = ((const struct commit_list *)a)->item->date; + timestamp_t b_date = ((const struct commit_list *)b)->item->date; + if (a_date < b_date) + return 1; + if (a_date > b_date) + return -1; + return 0; +} + +static void *commit_list_get_next(const void *a) +{ + return ((const struct commit_list *)a)->next; +} + +static void commit_list_set_next(void *a, void *next) +{ + ((struct commit_list *)a)->next = next; +} + +void commit_list_sort_by_date(struct commit_list **list) +{ + *list = llist_mergesort(*list, commit_list_get_next, commit_list_set_next, + commit_list_compare_by_date); +} + +struct commit *pop_most_recent_commit(struct commit_list **list, + unsigned int mark) +{ + struct commit *ret = pop_commit(list); + struct commit_list *parents = ret->parents; + + while (parents) { + struct commit *commit = parents->item; + if (!parse_commit(commit) && !(commit->object.flags & mark)) { + commit->object.flags |= mark; + commit_list_insert_by_date(commit, list); + } + parents = parents->next; + } + return ret; +} + +static void clear_commit_marks_1(struct commit_list **plist, + struct commit *commit, unsigned int mark) +{ + while (commit) { + struct commit_list *parents; + + if (!(mark & commit->object.flags)) + return; + + commit->object.flags &= ~mark; + + parents = commit->parents; + if (!parents) + return; + + while ((parents = parents->next)) + commit_list_insert(parents->item, plist); + + commit = commit->parents->item; + } +} + +void clear_commit_marks_many(int nr, struct commit **commit, unsigned int mark) +{ + struct commit_list *list = NULL; + + while (nr--) { + clear_commit_marks_1(&list, *commit, mark); + commit++; + } + while (list) + clear_commit_marks_1(&list, pop_commit(&list), mark); +} + +void clear_commit_marks(struct commit *commit, unsigned int mark) +{ + clear_commit_marks_many(1, &commit, mark); +} + +struct commit *pop_commit(struct commit_list **stack) +{ + struct commit_list *top = *stack; + struct commit *item = top ? top->item : NULL; + + if (top) { + *stack = top->next; + free(top); + } + return item; +} + +/* + * Topological sort support + */ + +/* count number of children that have not been emitted */ +define_commit_slab(indegree_slab, int); + +define_commit_slab(author_date_slab, timestamp_t); + +void record_author_date(struct author_date_slab *author_date, + struct commit *commit) +{ + const char *buffer = get_commit_buffer(commit, NULL); + struct ident_split ident; + const char *ident_line; + size_t ident_len; + char *date_end; + timestamp_t date; + + ident_line = find_commit_header(buffer, "author", &ident_len); + if (!ident_line) + goto fail_exit; /* no author line */ + if (split_ident_line(&ident, ident_line, ident_len) || + !ident.date_begin || !ident.date_end) + goto fail_exit; /* malformed "author" line */ + + date = parse_timestamp(ident.date_begin, &date_end, 10); + if (date_end != ident.date_end) + goto fail_exit; /* malformed date */ + *(author_date_slab_at(author_date, commit)) = date; + +fail_exit: + unuse_commit_buffer(commit, buffer); +} + +int compare_commits_by_author_date(const void *a_, const void *b_, + void *cb_data) +{ + const struct commit *a = a_, *b = b_; + struct author_date_slab *author_date = cb_data; + timestamp_t a_date = *(author_date_slab_at(author_date, a)); + timestamp_t b_date = *(author_date_slab_at(author_date, b)); + + /* newer commits with larger date first */ + if (a_date < b_date) + return 1; + else if (a_date > b_date) + return -1; + return 0; +} + +int compare_commits_by_gen_then_commit_date(const void *a_, const void *b_, void *unused) +{ + const struct commit *a = a_, *b = b_; + + /* newer commits first */ + if (a->generation < b->generation) + return 1; + else if (a->generation > b->generation) + return -1; + + /* use date as a heuristic when generations are equal */ + if (a->date < b->date) + return 1; + else if (a->date > b->date) + return -1; + return 0; +} + +int compare_commits_by_commit_date(const void *a_, const void *b_, void *unused) +{ + const struct commit *a = a_, *b = b_; + /* newer commits with larger date first */ + if (a->date < b->date) + return 1; + else if (a->date > b->date) + return -1; + return 0; +} + +/* + * Performs an in-place topological sort on the list supplied. + */ +void sort_in_topological_order(struct commit_list **list, enum rev_sort_order sort_order) +{ + struct commit_list *next, *orig = *list; + struct commit_list **pptr; + struct indegree_slab indegree; + struct prio_queue queue; + struct commit *commit; + struct author_date_slab author_date; + + if (!orig) + return; + *list = NULL; + + init_indegree_slab(&indegree); + memset(&queue, '\0', sizeof(queue)); + + switch (sort_order) { + default: /* REV_SORT_IN_GRAPH_ORDER */ + queue.compare = NULL; + break; + case REV_SORT_BY_COMMIT_DATE: + queue.compare = compare_commits_by_commit_date; + break; + case REV_SORT_BY_AUTHOR_DATE: + init_author_date_slab(&author_date); + queue.compare = compare_commits_by_author_date; + queue.cb_data = &author_date; + break; + } + + /* Mark them and clear the indegree */ + for (next = orig; next; next = next->next) { + struct commit *commit = next->item; + *(indegree_slab_at(&indegree, commit)) = 1; + /* also record the author dates, if needed */ + if (sort_order == REV_SORT_BY_AUTHOR_DATE) + record_author_date(&author_date, commit); + } + + /* update the indegree */ + for (next = orig; next; next = next->next) { + struct commit_list *parents = next->item->parents; + while (parents) { + struct commit *parent = parents->item; + int *pi = indegree_slab_at(&indegree, parent); + + if (*pi) + (*pi)++; + parents = parents->next; + } + } + + /* + * find the tips + * + * tips are nodes not reachable from any other node in the list + * + * the tips serve as a starting set for the work queue. + */ + for (next = orig; next; next = next->next) { + struct commit *commit = next->item; + + if (*(indegree_slab_at(&indegree, commit)) == 1) + prio_queue_put(&queue, commit); + } + + /* + * This is unfortunate; the initial tips need to be shown + * in the order given from the revision traversal machinery. + */ + if (sort_order == REV_SORT_IN_GRAPH_ORDER) + prio_queue_reverse(&queue); + + /* We no longer need the commit list */ + free_commit_list(orig); + + pptr = list; + *list = NULL; + while ((commit = prio_queue_get(&queue)) != NULL) { + struct commit_list *parents; + + for (parents = commit->parents; parents ; parents = parents->next) { + struct commit *parent = parents->item; + int *pi = indegree_slab_at(&indegree, parent); + + if (!*pi) + continue; + + /* + * parents are only enqueued for emission + * when all their children have been emitted thereby + * guaranteeing topological order. + */ + if (--(*pi) == 1) + prio_queue_put(&queue, parent); + } + /* + * all children of commit have already been + * emitted. we can emit it now. + */ + *(indegree_slab_at(&indegree, commit)) = 0; + + pptr = &commit_list_insert(commit, pptr)->next; + } + + clear_indegree_slab(&indegree); + clear_prio_queue(&queue); + if (sort_order == REV_SORT_BY_AUTHOR_DATE) + clear_author_date_slab(&author_date); +} + +struct rev_collect { + struct commit **commit; + int nr; + int alloc; + unsigned int initial : 1; +}; + +static void add_one_commit(struct object_id *oid, struct rev_collect *revs) +{ + struct commit *commit; + + if (is_null_oid(oid)) + return; + + commit = lookup_commit(the_repository, oid); + if (!commit || + (commit->object.flags & TMP_MARK) || + parse_commit(commit)) + return; + + ALLOC_GROW(revs->commit, revs->nr + 1, revs->alloc); + revs->commit[revs->nr++] = commit; + commit->object.flags |= TMP_MARK; +} + +static int collect_one_reflog_ent(struct object_id *ooid, struct object_id *noid, + const char *ident, timestamp_t timestamp, + int tz, const char *message, void *cbdata) +{ + struct rev_collect *revs = cbdata; + + if (revs->initial) { + revs->initial = 0; + add_one_commit(ooid, revs); + } + add_one_commit(noid, revs); + return 0; +} + +struct commit *get_fork_point(const char *refname, struct commit *commit) +{ + struct object_id oid; + struct rev_collect revs; + struct commit_list *bases; + int i; + struct commit *ret = NULL; + + memset(&revs, 0, sizeof(revs)); + revs.initial = 1; + for_each_reflog_ent(refname, collect_one_reflog_ent, &revs); + + if (!revs.nr && !get_oid(refname, &oid)) + add_one_commit(&oid, &revs); + + for (i = 0; i < revs.nr; i++) + revs.commit[i]->object.flags &= ~TMP_MARK; + + bases = get_merge_bases_many(commit, revs.nr, revs.commit); + + /* + * There should be one and only one merge base, when we found + * a common ancestor among reflog entries. + */ + if (!bases || bases->next) + goto cleanup_return; + + /* And the found one must be one of the reflog entries */ + for (i = 0; i < revs.nr; i++) + if (&bases->item->object == &revs.commit[i]->object) + break; /* found */ + if (revs.nr <= i) + goto cleanup_return; + + ret = bases->item; + +cleanup_return: + free_commit_list(bases); + return ret; +} + +static const char gpg_sig_header[] = "gpgsig"; +static const int gpg_sig_header_len = sizeof(gpg_sig_header) - 1; + +static int do_sign_commit(struct strbuf *buf, const char *keyid) +{ + struct strbuf sig = STRBUF_INIT; + int inspos, copypos; + const char *eoh; + + /* find the end of the header */ + eoh = strstr(buf->buf, "\n\n"); + if (!eoh) + inspos = buf->len; + else + inspos = eoh - buf->buf + 1; + + if (!keyid || !*keyid) + keyid = get_signing_key(); + if (sign_buffer(buf, &sig, keyid)) { + strbuf_release(&sig); + return -1; + } + + for (copypos = 0; sig.buf[copypos]; ) { + const char *bol = sig.buf + copypos; + const char *eol = strchrnul(bol, '\n'); + int len = (eol - bol) + !!*eol; + + if (!copypos) { + strbuf_insert(buf, inspos, gpg_sig_header, gpg_sig_header_len); + inspos += gpg_sig_header_len; + } + strbuf_insert(buf, inspos++, " ", 1); + strbuf_insert(buf, inspos, bol, len); + inspos += len; + copypos += len; + } + strbuf_release(&sig); + return 0; +} + +int parse_signed_commit(const struct commit *commit, + struct strbuf *payload, struct strbuf *signature) +{ + + unsigned long size; + const char *buffer = get_commit_buffer(commit, &size); + int in_signature, saw_signature = -1; + const char *line, *tail; + + line = buffer; + tail = buffer + size; + in_signature = 0; + saw_signature = 0; + while (line < tail) { + const char *sig = NULL; + const char *next = memchr(line, '\n', tail - line); + + next = next ? next + 1 : tail; + if (in_signature && line[0] == ' ') + sig = line + 1; + else if (starts_with(line, gpg_sig_header) && + line[gpg_sig_header_len] == ' ') + sig = line + gpg_sig_header_len + 1; + if (sig) { + strbuf_add(signature, sig, next - sig); + saw_signature = 1; + in_signature = 1; + } else { + if (*line == '\n') + /* dump the whole remainder of the buffer */ + next = tail; + strbuf_add(payload, line, next - line); + in_signature = 0; + } + line = next; + } + unuse_commit_buffer(commit, buffer); + return saw_signature; +} + +int remove_signature(struct strbuf *buf) +{ + const char *line = buf->buf; + const char *tail = buf->buf + buf->len; + int in_signature = 0; + const char *sig_start = NULL; + const char *sig_end = NULL; + + while (line < tail) { + const char *next = memchr(line, '\n', tail - line); + next = next ? next + 1 : tail; + + if (in_signature && line[0] == ' ') + sig_end = next; + else if (starts_with(line, gpg_sig_header) && + line[gpg_sig_header_len] == ' ') { + sig_start = line; + sig_end = next; + in_signature = 1; + } else { + if (*line == '\n') + /* dump the whole remainder of the buffer */ + next = tail; + in_signature = 0; + } + line = next; + } + + if (sig_start) + strbuf_remove(buf, sig_start - buf->buf, sig_end - sig_start); + + return sig_start != NULL; +} + +static void handle_signed_tag(struct commit *parent, struct commit_extra_header ***tail) +{ + struct merge_remote_desc *desc; + struct commit_extra_header *mergetag; + char *buf; + unsigned long size, len; + enum object_type type; + + desc = merge_remote_util(parent); + if (!desc || !desc->obj) + return; + buf = read_object_file(&desc->obj->oid, &type, &size); + if (!buf || type != OBJ_TAG) + goto free_return; + len = parse_signature(buf, size); + if (size == len) + goto free_return; + /* + * We could verify this signature and either omit the tag when + * it does not validate, but the integrator may not have the + * public key of the signer of the tag he is merging, while a + * later auditor may have it while auditing, so let's not run + * verify-signed-buffer here for now... + * + * if (verify_signed_buffer(buf, len, buf + len, size - len, ...)) + * warn("warning: signed tag unverified."); + */ + mergetag = xcalloc(1, sizeof(*mergetag)); + mergetag->key = xstrdup("mergetag"); + mergetag->value = buf; + mergetag->len = size; + + **tail = mergetag; + *tail = &mergetag->next; + return; + +free_return: + free(buf); +} + +int check_commit_signature(const struct commit *commit, struct signature_check *sigc) +{ + struct strbuf payload = STRBUF_INIT; + struct strbuf signature = STRBUF_INIT; + int ret = 1; + + sigc->result = 'N'; + + if (parse_signed_commit(commit, &payload, &signature) <= 0) + goto out; + ret = check_signature(payload.buf, payload.len, signature.buf, + signature.len, sigc); + + out: + strbuf_release(&payload); + strbuf_release(&signature); + + return ret; +} + +void verify_merge_signature(struct commit *commit, int verbosity) +{ + char hex[GIT_MAX_HEXSZ + 1]; + struct signature_check signature_check; + memset(&signature_check, 0, sizeof(signature_check)); + + check_commit_signature(commit, &signature_check); + + find_unique_abbrev_r(hex, &commit->object.oid, DEFAULT_ABBREV); + switch (signature_check.result) { + case 'G': + break; + case 'U': + die(_("Commit %s has an untrusted GPG signature, " + "allegedly by %s."), hex, signature_check.signer); + case 'B': + die(_("Commit %s has a bad GPG signature " + "allegedly by %s."), hex, signature_check.signer); + default: /* 'N' */ + die(_("Commit %s does not have a GPG signature."), hex); + } + if (verbosity >= 0 && signature_check.result == 'G') + printf(_("Commit %s has a good GPG signature by %s\n"), + hex, signature_check.signer); + + signature_check_clear(&signature_check); +} + +void append_merge_tag_headers(struct commit_list *parents, + struct commit_extra_header ***tail) +{ + while (parents) { + struct commit *parent = parents->item; + handle_signed_tag(parent, tail); + parents = parents->next; + } +} + +static void add_extra_header(struct strbuf *buffer, + struct commit_extra_header *extra) +{ + strbuf_addstr(buffer, extra->key); + if (extra->len) + strbuf_add_lines(buffer, " ", extra->value, extra->len); + else + strbuf_addch(buffer, '\n'); +} + +struct commit_extra_header *read_commit_extra_headers(struct commit *commit, + const char **exclude) +{ + struct commit_extra_header *extra = NULL; + unsigned long size; + const char *buffer = get_commit_buffer(commit, &size); + extra = read_commit_extra_header_lines(buffer, size, exclude); + unuse_commit_buffer(commit, buffer); + return extra; +} + +int for_each_mergetag(each_mergetag_fn fn, struct commit *commit, void *data) +{ + struct commit_extra_header *extra, *to_free; + int res = 0; + + to_free = read_commit_extra_headers(commit, NULL); + for (extra = to_free; !res && extra; extra = extra->next) { + if (strcmp(extra->key, "mergetag")) + continue; /* not a merge tag */ + res = fn(commit, extra, data); + } + free_commit_extra_headers(to_free); + return res; +} + +static inline int standard_header_field(const char *field, size_t len) +{ + return ((len == 4 && !memcmp(field, "tree", 4)) || + (len == 6 && !memcmp(field, "parent", 6)) || + (len == 6 && !memcmp(field, "author", 6)) || + (len == 9 && !memcmp(field, "committer", 9)) || + (len == 8 && !memcmp(field, "encoding", 8))); +} + +static int excluded_header_field(const char *field, size_t len, const char **exclude) +{ + if (!exclude) + return 0; + + while (*exclude) { + size_t xlen = strlen(*exclude); + if (len == xlen && !memcmp(field, *exclude, xlen)) + return 1; + exclude++; + } + return 0; +} + +static struct commit_extra_header *read_commit_extra_header_lines( + const char *buffer, size_t size, + const char **exclude) +{ + struct commit_extra_header *extra = NULL, **tail = &extra, *it = NULL; + const char *line, *next, *eof, *eob; + struct strbuf buf = STRBUF_INIT; + + for (line = buffer, eob = line + size; + line < eob && *line != '\n'; + line = next) { + next = memchr(line, '\n', eob - line); + next = next ? next + 1 : eob; + if (*line == ' ') { + /* continuation */ + if (it) + strbuf_add(&buf, line + 1, next - (line + 1)); + continue; + } + if (it) + it->value = strbuf_detach(&buf, &it->len); + strbuf_reset(&buf); + it = NULL; + + eof = memchr(line, ' ', next - line); + if (!eof) + eof = next; + else if (standard_header_field(line, eof - line) || + excluded_header_field(line, eof - line, exclude)) + continue; + + it = xcalloc(1, sizeof(*it)); + it->key = xmemdupz(line, eof-line); + *tail = it; + tail = &it->next; + if (eof + 1 < next) + strbuf_add(&buf, eof + 1, next - (eof + 1)); + } + if (it) + it->value = strbuf_detach(&buf, &it->len); + return extra; +} + +void free_commit_extra_headers(struct commit_extra_header *extra) +{ + while (extra) { + struct commit_extra_header *next = extra->next; + free(extra->key); + free(extra->value); + free(extra); + extra = next; + } +} + +int commit_tree(const char *msg, size_t msg_len, const struct object_id *tree, + struct commit_list *parents, struct object_id *ret, + const char *author, const char *sign_commit) +{ + struct commit_extra_header *extra = NULL, **tail = &extra; + int result; + + append_merge_tag_headers(parents, &tail); + result = commit_tree_extended(msg, msg_len, tree, parents, ret, + author, sign_commit, extra); + free_commit_extra_headers(extra); + return result; +} + +static int find_invalid_utf8(const char *buf, int len) +{ + int offset = 0; + static const unsigned int max_codepoint[] = { + 0x7f, 0x7ff, 0xffff, 0x10ffff + }; + + while (len) { + unsigned char c = *buf++; + int bytes, bad_offset; + unsigned int codepoint; + unsigned int min_val, max_val; + + len--; + offset++; + + /* Simple US-ASCII? No worries. */ + if (c < 0x80) + continue; + + bad_offset = offset-1; + + /* + * Count how many more high bits set: that's how + * many more bytes this sequence should have. + */ + bytes = 0; + while (c & 0x40) { + c <<= 1; + bytes++; + } + + /* + * Must be between 1 and 3 more bytes. Longer sequences result in + * codepoints beyond U+10FFFF, which are guaranteed never to exist. + */ + if (bytes < 1 || 3 < bytes) + return bad_offset; + + /* Do we *have* that many bytes? */ + if (len < bytes) + return bad_offset; + + /* + * Place the encoded bits at the bottom of the value and compute the + * valid range. + */ + codepoint = (c & 0x7f) >> bytes; + min_val = max_codepoint[bytes-1] + 1; + max_val = max_codepoint[bytes]; + + offset += bytes; + len -= bytes; + + /* And verify that they are good continuation bytes */ + do { + codepoint <<= 6; + codepoint |= *buf & 0x3f; + if ((*buf++ & 0xc0) != 0x80) + return bad_offset; + } while (--bytes); + + /* Reject codepoints that are out of range for the sequence length. */ + if (codepoint < min_val || codepoint > max_val) + return bad_offset; + /* Surrogates are only for UTF-16 and cannot be encoded in UTF-8. */ + if ((codepoint & 0x1ff800) == 0xd800) + return bad_offset; + /* U+xxFFFE and U+xxFFFF are guaranteed non-characters. */ + if ((codepoint & 0xfffe) == 0xfffe) + return bad_offset; + /* So are anything in the range U+FDD0..U+FDEF. */ + if (codepoint >= 0xfdd0 && codepoint <= 0xfdef) + return bad_offset; + } + return -1; +} + +/* + * This verifies that the buffer is in proper utf8 format. + * + * If it isn't, it assumes any non-utf8 characters are Latin1, + * and does the conversion. + */ +static int verify_utf8(struct strbuf *buf) +{ + int ok = 1; + long pos = 0; + + for (;;) { + int bad; + unsigned char c; + unsigned char replace[2]; + + bad = find_invalid_utf8(buf->buf + pos, buf->len - pos); + if (bad < 0) + return ok; + pos += bad; + ok = 0; + c = buf->buf[pos]; + strbuf_remove(buf, pos, 1); + + /* We know 'c' must be in the range 128-255 */ + replace[0] = 0xc0 + (c >> 6); + replace[1] = 0x80 + (c & 0x3f); + strbuf_insert(buf, pos, replace, 2); + pos += 2; + } +} + +static const char commit_utf8_warn[] = +N_("Warning: commit message did not conform to UTF-8.\n" + "You may want to amend it after fixing the message, or set the config\n" + "variable i18n.commitencoding to the encoding your project uses.\n"); + +int commit_tree_extended(const char *msg, size_t msg_len, + const struct object_id *tree, + struct commit_list *parents, struct object_id *ret, + const char *author, const char *sign_commit, + struct commit_extra_header *extra) +{ + int result; + int encoding_is_utf8; + struct strbuf buffer; + + assert_oid_type(tree, OBJ_TREE); + + if (memchr(msg, '\0', msg_len)) + return error("a NUL byte in commit log message not allowed."); + + /* Not having i18n.commitencoding is the same as having utf-8 */ + encoding_is_utf8 = is_encoding_utf8(git_commit_encoding); + + strbuf_init(&buffer, 8192); /* should avoid reallocs for the headers */ + strbuf_addf(&buffer, "tree %s\n", oid_to_hex(tree)); + + /* + * NOTE! This ordering means that the same exact tree merged with a + * different order of parents will be a _different_ changeset even + * if everything else stays the same. + */ + while (parents) { + struct commit *parent = pop_commit(&parents); + strbuf_addf(&buffer, "parent %s\n", + oid_to_hex(&parent->object.oid)); + } + + /* Person/date information */ + if (!author) + author = git_author_info(IDENT_STRICT); + strbuf_addf(&buffer, "author %s\n", author); + strbuf_addf(&buffer, "committer %s\n", git_committer_info(IDENT_STRICT)); + if (!encoding_is_utf8) + strbuf_addf(&buffer, "encoding %s\n", git_commit_encoding); + + while (extra) { + add_extra_header(&buffer, extra); + extra = extra->next; + } + strbuf_addch(&buffer, '\n'); + + /* And add the comment */ + strbuf_add(&buffer, msg, msg_len); + + /* And check the encoding */ + if (encoding_is_utf8 && !verify_utf8(&buffer)) + fprintf(stderr, _(commit_utf8_warn)); + + if (sign_commit && do_sign_commit(&buffer, sign_commit)) { + result = -1; + goto out; + } + + result = write_object_file(buffer.buf, buffer.len, commit_type, ret); +out: + strbuf_release(&buffer); + return result; +} + +define_commit_slab(merge_desc_slab, struct merge_remote_desc *); +static struct merge_desc_slab merge_desc_slab = COMMIT_SLAB_INIT(1, merge_desc_slab); + +struct merge_remote_desc *merge_remote_util(struct commit *commit) +{ + return *merge_desc_slab_at(&merge_desc_slab, commit); +} + +void set_merge_remote_desc(struct commit *commit, + const char *name, struct object *obj) +{ + struct merge_remote_desc *desc; + FLEX_ALLOC_STR(desc, name, name); + desc->obj = obj; + *merge_desc_slab_at(&merge_desc_slab, commit) = desc; +} + +struct commit *get_merge_parent(const char *name) +{ + struct object *obj; + struct commit *commit; + struct object_id oid; + if (get_oid(name, &oid)) + return NULL; + obj = parse_object(the_repository, &oid); + commit = (struct commit *)peel_to_type(name, 0, obj, OBJ_COMMIT); + if (commit && !merge_remote_util(commit)) + set_merge_remote_desc(commit, name, obj); + return commit; +} + +/* + * Append a commit to the end of the commit_list. + * + * next starts by pointing to the variable that holds the head of an + * empty commit_list, and is updated to point to the "next" field of + * the last item on the list as new commits are appended. + * + * Usage example: + * + * struct commit_list *list; + * struct commit_list **next = &list; + * + * next = commit_list_append(c1, next); + * next = commit_list_append(c2, next); + * assert(commit_list_count(list) == 2); + * return list; + */ +struct commit_list **commit_list_append(struct commit *commit, + struct commit_list **next) +{ + struct commit_list *new_commit = xmalloc(sizeof(struct commit_list)); + new_commit->item = commit; + *next = new_commit; + new_commit->next = NULL; + return &new_commit->next; +} + +const char *find_commit_header(const char *msg, const char *key, size_t *out_len) +{ + int key_len = strlen(key); + const char *line = msg; + + while (line) { + const char *eol = strchrnul(line, '\n'); + + if (line == eol) + return NULL; + + if (eol - line > key_len && + !strncmp(line, key, key_len) && + line[key_len] == ' ') { + *out_len = eol - line - key_len - 1; + return line + key_len + 1; + } + line = *eol ? eol + 1 : NULL; + } + return NULL; +} + +/* + * Inspect the given string and determine the true "end" of the log message, in + * order to find where to put a new Signed-off-by: line. Ignored are + * trailing comment lines and blank lines. To support "git commit -s + * --amend" on an existing commit, we also ignore "Conflicts:". To + * support "git commit -v", we truncate at cut lines. + * + * Returns the number of bytes from the tail to ignore, to be fed as + * the second parameter to append_signoff(). + */ +size_t ignore_non_trailer(const char *buf, size_t len) +{ + size_t boc = 0; + size_t bol = 0; + int in_old_conflicts_block = 0; + size_t cutoff = wt_status_locate_end(buf, len); + + while (bol < cutoff) { + const char *next_line = memchr(buf + bol, '\n', len - bol); + + if (!next_line) + next_line = buf + len; + else + next_line++; + + if (buf[bol] == comment_line_char || buf[bol] == '\n') { + /* is this the first of the run of comments? */ + if (!boc) + boc = bol; + /* otherwise, it is just continuing */ + } else if (starts_with(buf + bol, "Conflicts:\n")) { + in_old_conflicts_block = 1; + if (!boc) + boc = bol; + } else if (in_old_conflicts_block && buf[bol] == '\t') { + ; /* a pathname in the conflicts block */ + } else if (boc) { + /* the previous was not trailing comment */ + boc = 0; + in_old_conflicts_block = 0; + } + bol = next_line - buf; + } + return boc ? len - boc : len - cutoff; +} |