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-rw-r--r--commit.c1709
1 files changed, 1709 insertions, 0 deletions
diff --git a/commit.c b/commit.c
new file mode 100644
index 0000000000..494615d6ff
--- /dev/null
+++ b/commit.c
@@ -0,0 +1,1709 @@
+#include "cache.h"
+#include "tag.h"
+#include "commit.h"
+#include "pkt-line.h"
+#include "utf8.h"
+#include "diff.h"
+#include "revision.h"
+#include "notes.h"
+#include "gpg-interface.h"
+#include "mergesort.h"
+#include "commit-slab.h"
+#include "prio-queue.h"
+#include "sha1-lookup.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(const unsigned char *sha1,
+ int quiet)
+{
+ struct object *obj = deref_tag(parse_object(sha1), NULL, 0);
+
+ if (!obj)
+ return NULL;
+ return object_as_type(obj, OBJ_COMMIT, quiet);
+}
+
+struct commit *lookup_commit_reference(const unsigned char *sha1)
+{
+ return lookup_commit_reference_gently(sha1, 0);
+}
+
+struct commit *lookup_commit_or_die(const unsigned char *sha1, const char *ref_name)
+{
+ struct commit *c = lookup_commit_reference(sha1);
+ if (!c)
+ die(_("could not parse %s"), ref_name);
+ if (hashcmp(sha1, c->object.sha1)) {
+ warning(_("%s %s is not a commit!"),
+ ref_name, sha1_to_hex(sha1));
+ }
+ return c;
+}
+
+struct commit *lookup_commit(const unsigned char *sha1)
+{
+ struct object *obj = lookup_object(sha1);
+ if (!obj)
+ return create_object(sha1, alloc_commit_node());
+ return object_as_type(obj, OBJ_COMMIT, 0);
+}
+
+struct commit *lookup_commit_reference_by_name(const char *name)
+{
+ struct object_id oid;
+ struct commit *commit;
+
+ if (get_sha1_committish(name, oid.hash))
+ return NULL;
+ commit = lookup_commit_reference(oid.hash);
+ if (parse_commit(commit))
+ return NULL;
+ return commit;
+}
+
+static unsigned long 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 strtoul will stop at buf-1 */
+ return strtoul(dateptr, NULL, 10);
+}
+
+static struct commit_graft **commit_graft;
+static int commit_graft_alloc, commit_graft_nr;
+
+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(const unsigned char *sha1)
+{
+ return sha1_pos(sha1, commit_graft, commit_graft_nr,
+ commit_graft_sha1_access);
+}
+
+int register_commit_graft(struct commit_graft *graft, int ignore_dups)
+{
+ int pos = commit_graft_pos(graft->oid.hash);
+
+ if (0 <= pos) {
+ if (ignore_dups)
+ free(graft);
+ else {
+ free(commit_graft[pos]);
+ commit_graft[pos] = graft;
+ }
+ return 1;
+ }
+ pos = -pos - 1;
+ ALLOC_GROW(commit_graft, commit_graft_nr + 1, commit_graft_alloc);
+ commit_graft_nr++;
+ if (pos < commit_graft_nr)
+ memmove(commit_graft + pos + 1,
+ commit_graft + pos,
+ (commit_graft_nr - pos - 1) *
+ sizeof(*commit_graft));
+ commit_graft[pos] = graft;
+ return 0;
+}
+
+struct commit_graft *read_graft_line(char *buf, int len)
+{
+ /* The format is just "Commit Parent1 Parent2 ...\n" */
+ int i;
+ struct commit_graft *graft = NULL;
+ const int entry_size = GIT_SHA1_HEXSZ + 1;
+
+ while (len && isspace(buf[len-1]))
+ buf[--len] = '\0';
+ if (buf[0] == '#' || buf[0] == '\0')
+ return NULL;
+ if ((len + 1) % entry_size)
+ goto bad_graft_data;
+ i = (len + 1) / entry_size - 1;
+ graft = xmalloc(sizeof(*graft) + GIT_SHA1_RAWSZ * i);
+ graft->nr_parent = i;
+ if (get_oid_hex(buf, &graft->oid))
+ goto bad_graft_data;
+ for (i = GIT_SHA1_HEXSZ; i < len; i += entry_size) {
+ if (buf[i] != ' ')
+ goto bad_graft_data;
+ if (get_sha1_hex(buf + i + 1, graft->parent[i/entry_size].hash))
+ goto bad_graft_data;
+ }
+ return graft;
+
+bad_graft_data:
+ error("bad graft data: %s", buf);
+ free(graft);
+ return NULL;
+}
+
+static int read_graft_file(const char *graft_file)
+{
+ FILE *fp = fopen(graft_file, "r");
+ struct strbuf buf = STRBUF_INIT;
+ if (!fp)
+ return -1;
+ while (!strbuf_getwholeline(&buf, fp, '\n')) {
+ /* The format is just "Commit Parent1 Parent2 ...\n" */
+ struct commit_graft *graft = read_graft_line(buf.buf, buf.len);
+ if (!graft)
+ continue;
+ if (register_commit_graft(graft, 1))
+ error("duplicate graft data: %s", buf.buf);
+ }
+ fclose(fp);
+ strbuf_release(&buf);
+ return 0;
+}
+
+static void prepare_commit_graft(void)
+{
+ static int commit_graft_prepared;
+ char *graft_file;
+
+ if (commit_graft_prepared)
+ return;
+ graft_file = get_graft_file();
+ read_graft_file(graft_file);
+ /* make sure shallows are read */
+ is_repository_shallow();
+ commit_graft_prepared = 1;
+}
+
+struct commit_graft *lookup_commit_graft(const unsigned char *sha1)
+{
+ int pos;
+ prepare_commit_graft();
+ pos = commit_graft_pos(sha1);
+ if (pos < 0)
+ return NULL;
+ return commit_graft[pos];
+}
+
+int for_each_commit_graft(each_commit_graft_fn fn, void *cb_data)
+{
+ int i, ret;
+ for (i = ret = 0; i < commit_graft_nr && !ret; i++)
+ ret = fn(commit_graft[i], cb_data);
+ return ret;
+}
+
+int unregister_shallow(const unsigned char *sha1)
+{
+ int pos = commit_graft_pos(sha1);
+ if (pos < 0)
+ return -1;
+ if (pos + 1 < commit_graft_nr)
+ memmove(commit_graft + pos, commit_graft + pos + 1,
+ sizeof(struct commit_graft *)
+ * (commit_graft_nr - pos - 1));
+ commit_graft_nr--;
+ return 0;
+}
+
+struct commit_buffer {
+ void *buffer;
+ unsigned long size;
+};
+define_commit_slab(buffer_slab, struct commit_buffer);
+static struct buffer_slab buffer_slab = COMMIT_SLAB_INIT(1, buffer_slab);
+
+void set_commit_buffer(struct commit *commit, void *buffer, unsigned long size)
+{
+ struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
+ v->buffer = buffer;
+ v->size = size;
+}
+
+const void *get_cached_commit_buffer(const struct commit *commit, unsigned long *sizep)
+{
+ struct commit_buffer *v = buffer_slab_peek(&buffer_slab, commit);
+ if (!v) {
+ if (sizep)
+ *sizep = 0;
+ return NULL;
+ }
+ if (sizep)
+ *sizep = v->size;
+ return v->buffer;
+}
+
+const void *get_commit_buffer(const struct commit *commit, unsigned long *sizep)
+{
+ const void *ret = get_cached_commit_buffer(commit, sizep);
+ if (!ret) {
+ enum object_type type;
+ unsigned long size;
+ ret = read_sha1_file(commit->object.sha1, &type, &size);
+ if (!ret)
+ die("cannot read commit object %s",
+ sha1_to_hex(commit->object.sha1));
+ if (type != OBJ_COMMIT)
+ die("expected commit for %s, got %s",
+ sha1_to_hex(commit->object.sha1), typename(type));
+ if (sizep)
+ *sizep = size;
+ }
+ return ret;
+}
+
+void unuse_commit_buffer(const struct commit *commit, const void *buffer)
+{
+ struct commit_buffer *v = buffer_slab_peek(&buffer_slab, commit);
+ if (!(v && v->buffer == buffer))
+ free((void *)buffer);
+}
+
+void free_commit_buffer(struct commit *commit)
+{
+ struct commit_buffer *v = buffer_slab_peek(&buffer_slab, commit);
+ if (v) {
+ free(v->buffer);
+ v->buffer = NULL;
+ v->size = 0;
+ }
+}
+
+const void *detach_commit_buffer(struct commit *commit, unsigned long *sizep)
+{
+ struct commit_buffer *v = buffer_slab_peek(&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 commit *item, const void *buffer, unsigned long size)
+{
+ 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 = GIT_SHA1_HEXSZ + 5;
+ const int parent_entry_len = GIT_SHA1_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", sha1_to_hex(item->object.sha1));
+ if (get_sha1_hex(bufptr + 5, parent.hash) < 0)
+ return error("bad tree pointer in commit %s",
+ sha1_to_hex(item->object.sha1));
+ item->tree = lookup_tree(parent.hash);
+ bufptr += tree_entry_len + 1; /* "tree " + "hex sha1" + "\n" */
+ pptr = &item->parents;
+
+ graft = lookup_commit_graft(item->object.sha1);
+ while (bufptr + parent_entry_len < tail && !memcmp(bufptr, "parent ", 7)) {
+ struct commit *new_parent;
+
+ if (tail <= bufptr + parent_entry_len + 1 ||
+ get_sha1_hex(bufptr + 7, parent.hash) ||
+ bufptr[parent_entry_len] != '\n')
+ return error("bad parents in commit %s", sha1_to_hex(item->object.sha1));
+ 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(parent.hash);
+ 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(graft->parent[i].hash);
+ if (!new_parent)
+ continue;
+ pptr = &commit_list_insert(new_parent, pptr)->next;
+ }
+ }
+ item->date = parse_commit_date(bufptr, tail);
+
+ return 0;
+}
+
+int parse_commit_gently(struct commit *item, int quiet_on_missing)
+{
+ enum object_type type;
+ void *buffer;
+ unsigned long size;
+ int ret;
+
+ if (!item)
+ return -1;
+ if (item->object.parsed)
+ return 0;
+ buffer = read_sha1_file(item->object.sha1, &type, &size);
+ if (!buffer)
+ return quiet_on_missing ? -1 :
+ error("Could not read %s",
+ sha1_to_hex(item->object.sha1));
+ if (type != OBJ_COMMIT) {
+ free(buffer);
+ return error("Object %s not a commit",
+ sha1_to_hex(item->object.sha1));
+ }
+ ret = parse_commit_buffer(item, buffer, size);
+ if (save_commit_buffer && !ret) {
+ set_commit_buffer(item, buffer, size);
+ return 0;
+ }
+ free(buffer);
+ return ret;
+}
+
+void parse_commit_or_die(struct commit *item)
+{
+ if (parse_commit(item))
+ die("unable to parse commit %s",
+ item ? sha1_to_hex(item->object.sha1) : "(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 += 2;
+ for (eol = p; *eol && *eol != '\n'; eol++)
+ ; /* do nothing */
+ } 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) {
+ struct commit_list *temp = list;
+ list = temp->next;
+ free(temp);
+ }
+}
+
+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)
+{
+ unsigned long a_date = ((const struct commit_list *)a)->item->date;
+ unsigned long 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 = (*list)->item;
+ struct commit_list *parents = ret->parents;
+ struct commit_list *old = *list;
+
+ *list = (*list)->next;
+ free(old);
+
+ 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--) {
+ commit_list_insert(*commit, &list);
+ 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);
+}
+
+void clear_commit_marks_for_object_array(struct object_array *a, unsigned mark)
+{
+ struct object *object;
+ struct commit *commit;
+ unsigned int i;
+
+ for (i = 0; i < a->nr; i++) {
+ object = a->objects[i].item;
+ commit = lookup_commit_reference_gently(object->sha1, 1);
+ if (commit)
+ clear_commit_marks(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);
+
+/* record author-date for each commit object */
+define_commit_slab(author_date_slab, unsigned long);
+
+static 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;
+ unsigned long 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 = strtoul(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);
+}
+
+static 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;
+ unsigned long a_date = *(author_date_slab_at(author_date, a));
+ unsigned long 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_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);
+}
+
+/* merge-base stuff */
+
+/* Remember to update object flag allocation in object.h */
+#define PARENT1 (1u<<16)
+#define PARENT2 (1u<<17)
+#define STALE (1u<<18)
+#define RESULT (1u<<19)
+
+static const unsigned all_flags = (PARENT1 | PARENT2 | STALE | RESULT);
+
+static int queue_has_nonstale(struct prio_queue *queue)
+{
+ int i;
+ for (i = 0; i < queue->nr; i++) {
+ struct commit *commit = queue->array[i].data;
+ if (!(commit->object.flags & STALE))
+ return 1;
+ }
+ return 0;
+}
+
+/* all input commits in one and twos[] must have been parsed! */
+static struct commit_list *paint_down_to_common(struct commit *one, int n, struct commit **twos)
+{
+ struct prio_queue queue = { compare_commits_by_commit_date };
+ struct commit_list *result = NULL;
+ int i;
+
+ one->object.flags |= PARENT1;
+ if (!n) {
+ commit_list_append(one, &result);
+ return result;
+ }
+ prio_queue_put(&queue, one);
+
+ for (i = 0; i < n; i++) {
+ twos[i]->object.flags |= PARENT2;
+ prio_queue_put(&queue, twos[i]);
+ }
+
+ while (queue_has_nonstale(&queue)) {
+ struct commit *commit = prio_queue_get(&queue);
+ struct commit_list *parents;
+ int flags;
+
+ flags = commit->object.flags & (PARENT1 | PARENT2 | STALE);
+ if (flags == (PARENT1 | PARENT2)) {
+ if (!(commit->object.flags & RESULT)) {
+ commit->object.flags |= RESULT;
+ commit_list_insert_by_date(commit, &result);
+ }
+ /* Mark parents of a found merge stale */
+ flags |= STALE;
+ }
+ parents = commit->parents;
+ while (parents) {
+ struct commit *p = parents->item;
+ parents = parents->next;
+ if ((p->object.flags & flags) == flags)
+ continue;
+ if (parse_commit(p))
+ return NULL;
+ p->object.flags |= flags;
+ prio_queue_put(&queue, p);
+ }
+ }
+
+ clear_prio_queue(&queue);
+ return result;
+}
+
+static struct commit_list *merge_bases_many(struct commit *one, int n, struct commit **twos)
+{
+ struct commit_list *list = NULL;
+ struct commit_list *result = NULL;
+ int i;
+
+ for (i = 0; i < n; i++) {
+ if (one == twos[i])
+ /*
+ * We do not mark this even with RESULT so we do not
+ * have to clean it up.
+ */
+ return commit_list_insert(one, &result);
+ }
+
+ if (parse_commit(one))
+ return NULL;
+ for (i = 0; i < n; i++) {
+ if (parse_commit(twos[i]))
+ return NULL;
+ }
+
+ list = paint_down_to_common(one, n, twos);
+
+ while (list) {
+ struct commit_list *next = list->next;
+ if (!(list->item->object.flags & STALE))
+ commit_list_insert_by_date(list->item, &result);
+ free(list);
+ list = next;
+ }
+ return result;
+}
+
+struct commit_list *get_octopus_merge_bases(struct commit_list *in)
+{
+ struct commit_list *i, *j, *k, *ret = NULL;
+
+ if (!in)
+ return ret;
+
+ commit_list_insert(in->item, &ret);
+
+ for (i = in->next; i; i = i->next) {
+ struct commit_list *new = NULL, *end = NULL;
+
+ for (j = ret; j; j = j->next) {
+ struct commit_list *bases;
+ bases = get_merge_bases(i->item, j->item);
+ if (!new)
+ new = bases;
+ else
+ end->next = bases;
+ for (k = bases; k; k = k->next)
+ end = k;
+ }
+ ret = new;
+ }
+ return ret;
+}
+
+static int remove_redundant(struct commit **array, int cnt)
+{
+ /*
+ * Some commit in the array may be an ancestor of
+ * another commit. Move such commit to the end of
+ * the array, and return the number of commits that
+ * are independent from each other.
+ */
+ struct commit **work;
+ unsigned char *redundant;
+ int *filled_index;
+ int i, j, filled;
+
+ work = xcalloc(cnt, sizeof(*work));
+ redundant = xcalloc(cnt, 1);
+ filled_index = xmalloc(sizeof(*filled_index) * (cnt - 1));
+
+ for (i = 0; i < cnt; i++)
+ parse_commit(array[i]);
+ for (i = 0; i < cnt; i++) {
+ struct commit_list *common;
+
+ if (redundant[i])
+ continue;
+ for (j = filled = 0; j < cnt; j++) {
+ if (i == j || redundant[j])
+ continue;
+ filled_index[filled] = j;
+ work[filled++] = array[j];
+ }
+ common = paint_down_to_common(array[i], filled, work);
+ if (array[i]->object.flags & PARENT2)
+ redundant[i] = 1;
+ for (j = 0; j < filled; j++)
+ if (work[j]->object.flags & PARENT1)
+ redundant[filled_index[j]] = 1;
+ clear_commit_marks(array[i], all_flags);
+ for (j = 0; j < filled; j++)
+ clear_commit_marks(work[j], all_flags);
+ free_commit_list(common);
+ }
+
+ /* Now collect the result */
+ memcpy(work, array, sizeof(*array) * cnt);
+ for (i = filled = 0; i < cnt; i++)
+ if (!redundant[i])
+ array[filled++] = work[i];
+ for (j = filled, i = 0; i < cnt; i++)
+ if (redundant[i])
+ array[j++] = work[i];
+ free(work);
+ free(redundant);
+ free(filled_index);
+ return filled;
+}
+
+static struct commit_list *get_merge_bases_many_0(struct commit *one,
+ int n,
+ struct commit **twos,
+ int cleanup)
+{
+ struct commit_list *list;
+ struct commit **rslt;
+ struct commit_list *result;
+ int cnt, i;
+
+ result = merge_bases_many(one, n, twos);
+ for (i = 0; i < n; i++) {
+ if (one == twos[i])
+ return result;
+ }
+ if (!result || !result->next) {
+ if (cleanup) {
+ clear_commit_marks(one, all_flags);
+ clear_commit_marks_many(n, twos, all_flags);
+ }
+ return result;
+ }
+
+ /* There are more than one */
+ cnt = commit_list_count(result);
+ rslt = xcalloc(cnt, sizeof(*rslt));
+ for (list = result, i = 0; list; list = list->next)
+ rslt[i++] = list->item;
+ free_commit_list(result);
+
+ clear_commit_marks(one, all_flags);
+ clear_commit_marks_many(n, twos, all_flags);
+
+ cnt = remove_redundant(rslt, cnt);
+ result = NULL;
+ for (i = 0; i < cnt; i++)
+ commit_list_insert_by_date(rslt[i], &result);
+ free(rslt);
+ return result;
+}
+
+struct commit_list *get_merge_bases_many(struct commit *one,
+ int n,
+ struct commit **twos)
+{
+ return get_merge_bases_many_0(one, n, twos, 1);
+}
+
+struct commit_list *get_merge_bases_many_dirty(struct commit *one,
+ int n,
+ struct commit **twos)
+{
+ return get_merge_bases_many_0(one, n, twos, 0);
+}
+
+struct commit_list *get_merge_bases(struct commit *one, struct commit *two)
+{
+ return get_merge_bases_many_0(one, 1, &two, 1);
+}
+
+/*
+ * Is "commit" a descendant of one of the elements on the "with_commit" list?
+ */
+int is_descendant_of(struct commit *commit, struct commit_list *with_commit)
+{
+ if (!with_commit)
+ return 1;
+ while (with_commit) {
+ struct commit *other;
+
+ other = with_commit->item;
+ with_commit = with_commit->next;
+ if (in_merge_bases(other, commit))
+ return 1;
+ }
+ return 0;
+}
+
+/*
+ * Is "commit" an ancestor of one of the "references"?
+ */
+int in_merge_bases_many(struct commit *commit, int nr_reference, struct commit **reference)
+{
+ struct commit_list *bases;
+ int ret = 0, i;
+
+ if (parse_commit(commit))
+ return ret;
+ for (i = 0; i < nr_reference; i++)
+ if (parse_commit(reference[i]))
+ return ret;
+
+ bases = paint_down_to_common(commit, nr_reference, reference);
+ if (commit->object.flags & PARENT2)
+ ret = 1;
+ clear_commit_marks(commit, all_flags);
+ clear_commit_marks_many(nr_reference, reference, all_flags);
+ free_commit_list(bases);
+ return ret;
+}
+
+/*
+ * Is "commit" an ancestor of (i.e. reachable from) the "reference"?
+ */
+int in_merge_bases(struct commit *commit, struct commit *reference)
+{
+ return in_merge_bases_many(commit, 1, &reference);
+}
+
+struct commit_list *reduce_heads(struct commit_list *heads)
+{
+ struct commit_list *p;
+ struct commit_list *result = NULL, **tail = &result;
+ struct commit **array;
+ int num_head, i;
+
+ if (!heads)
+ return NULL;
+
+ /* Uniquify */
+ for (p = heads; p; p = p->next)
+ p->item->object.flags &= ~STALE;
+ for (p = heads, num_head = 0; p; p = p->next) {
+ if (p->item->object.flags & STALE)
+ continue;
+ p->item->object.flags |= STALE;
+ num_head++;
+ }
+ array = xcalloc(num_head, sizeof(*array));
+ for (p = heads, i = 0; p; p = p->next) {
+ if (p->item->object.flags & STALE) {
+ array[i++] = p->item;
+ p->item->object.flags &= ~STALE;
+ }
+ }
+ num_head = remove_redundant(array, num_head);
+ for (i = 0; i < num_head; i++)
+ tail = &commit_list_insert(array[i], tail)->next;
+ return result;
+}
+
+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;
+
+ /* find the end of the header */
+ inspos = strstr(buf->buf, "\n\n") - 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_sha1_file(desc->obj->sha1, &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 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;
+}
+
+void for_each_mergetag(each_mergetag_fn fn, struct commit *commit, void *data)
+{
+ struct commit_extra_header *extra, *to_free;
+
+ to_free = read_commit_extra_headers(commit, NULL);
+ for (extra = to_free; extra; extra = extra->next) {
+ if (strcmp(extra->key, "mergetag"))
+ continue; /* not a merge tag */
+ fn(commit, extra, data);
+ }
+ free_commit_extra_headers(to_free);
+}
+
+static inline int standard_header_field(const char *field, size_t len)
+{
+ return ((len == 4 && !memcmp(field, "tree ", 5)) ||
+ (len == 6 && !memcmp(field, "parent ", 7)) ||
+ (len == 6 && !memcmp(field, "author ", 7)) ||
+ (len == 9 && !memcmp(field, "committer ", 10)) ||
+ (len == 8 && !memcmp(field, "encoding ", 9)));
+}
+
+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) && field[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 = strchr(line, ' ');
+ if (next <= eof)
+ eof = next;
+
+ 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 unsigned char *tree,
+ struct commit_list *parents, unsigned char *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[] =
+"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 unsigned char *tree,
+ struct commit_list *parents, unsigned char *ret,
+ const char *author, const char *sign_commit,
+ struct commit_extra_header *extra)
+{
+ int result;
+ int encoding_is_utf8;
+ struct strbuf buffer;
+
+ assert_sha1_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", sha1_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_list *next = parents->next;
+ struct commit *parent = parents->item;
+
+ strbuf_addf(&buffer, "parent %s\n",
+ sha1_to_hex(parent->object.sha1));
+ free(parents);
+ parents = next;
+ }
+
+ /* 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))
+ return -1;
+
+ result = write_sha1_file(buffer.buf, buffer.len, commit_type, ret);
+ strbuf_release(&buffer);
+ return result;
+}
+
+struct commit *get_merge_parent(const char *name)
+{
+ struct object *obj;
+ struct commit *commit;
+ struct object_id oid;
+ if (get_sha1(name, oid.hash))
+ return NULL;
+ obj = parse_object(oid.hash);
+ commit = (struct commit *)peel_to_type(name, 0, obj, OBJ_COMMIT);
+ if (commit && !commit->util) {
+ struct merge_remote_desc *desc;
+ desc = xmalloc(sizeof(*desc));
+ desc->obj = obj;
+ desc->name = strdup(name);
+ commit->util = desc;
+ }
+ 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 = xmalloc(sizeof(struct commit_list));
+ new->item = commit;
+ *next = new;
+ new->next = NULL;
+ return &new->next;
+}
+
+void print_commit_list(struct commit_list *list,
+ const char *format_cur,
+ const char *format_last)
+{
+ for ( ; list; list = list->next) {
+ const char *format = list->next ? format_cur : format_last;
+ printf(format, sha1_to_hex(list->item->object.sha1));
+ }
+}
+
+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 sb 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, and also the traditional
+ * "Conflicts:" block that is not commented out, so that we can use
+ * "git commit -s --amend" on an existing commit that forgot to remove
+ * it.
+ *
+ * Returns the number of bytes from the tail to ignore, to be fed as
+ * the second parameter to append_signoff().
+ */
+int ignore_non_trailer(struct strbuf *sb)
+{
+ int boc = 0;
+ int bol = 0;
+ int in_old_conflicts_block = 0;
+
+ while (bol < sb->len) {
+ char *next_line;
+
+ if (!(next_line = memchr(sb->buf + bol, '\n', sb->len - bol)))
+ next_line = sb->buf + sb->len;
+ else
+ next_line++;
+
+ if (sb->buf[bol] == comment_line_char || sb->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(sb->buf + bol, "Conflicts:\n")) {
+ in_old_conflicts_block = 1;
+ if (!boc)
+ boc = bol;
+ } else if (in_old_conflicts_block && sb->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 - sb->buf;
+ }
+ return boc ? sb->len - boc : 0;
+}