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-rw-r--r--revision.c1632
1 files changed, 1632 insertions, 0 deletions
diff --git a/revision.c b/revision.c
new file mode 100644
index 0000000..6e85aaa
--- /dev/null
+++ b/revision.c
@@ -0,0 +1,1632 @@
+#include "cache.h"
+#include "tag.h"
+#include "blob.h"
+#include "tree.h"
+#include "commit.h"
+#include "diff.h"
+#include "refs.h"
+#include "revision.h"
+#include "grep.h"
+#include "reflog-walk.h"
+#include "patch-ids.h"
+
+volatile show_early_output_fn_t show_early_output;
+
+static char *path_name(struct name_path *path, const char *name)
+{
+ struct name_path *p;
+ char *n, *m;
+ int nlen = strlen(name);
+ int len = nlen + 1;
+
+ for (p = path; p; p = p->up) {
+ if (p->elem_len)
+ len += p->elem_len + 1;
+ }
+ n = xmalloc(len);
+ m = n + len - (nlen + 1);
+ strcpy(m, name);
+ for (p = path; p; p = p->up) {
+ if (p->elem_len) {
+ m -= p->elem_len + 1;
+ memcpy(m, p->elem, p->elem_len);
+ m[p->elem_len] = '/';
+ }
+ }
+ return n;
+}
+
+void add_object(struct object *obj,
+ struct object_array *p,
+ struct name_path *path,
+ const char *name)
+{
+ add_object_array(obj, path_name(path, name), p);
+}
+
+static void mark_blob_uninteresting(struct blob *blob)
+{
+ if (blob->object.flags & UNINTERESTING)
+ return;
+ blob->object.flags |= UNINTERESTING;
+}
+
+void mark_tree_uninteresting(struct tree *tree)
+{
+ struct tree_desc desc;
+ struct name_entry entry;
+ struct object *obj = &tree->object;
+
+ if (obj->flags & UNINTERESTING)
+ return;
+ obj->flags |= UNINTERESTING;
+ if (!has_sha1_file(obj->sha1))
+ return;
+ if (parse_tree(tree) < 0)
+ die("bad tree %s", sha1_to_hex(obj->sha1));
+
+ init_tree_desc(&desc, tree->buffer, tree->size);
+ while (tree_entry(&desc, &entry)) {
+ switch (object_type(entry.mode)) {
+ case OBJ_TREE:
+ mark_tree_uninteresting(lookup_tree(entry.sha1));
+ break;
+ case OBJ_BLOB:
+ mark_blob_uninteresting(lookup_blob(entry.sha1));
+ break;
+ default:
+ /* Subproject commit - not in this repository */
+ break;
+ }
+ }
+
+ /*
+ * We don't care about the tree any more
+ * after it has been marked uninteresting.
+ */
+ free(tree->buffer);
+ tree->buffer = NULL;
+}
+
+void mark_parents_uninteresting(struct commit *commit)
+{
+ struct commit_list *parents = commit->parents;
+
+ while (parents) {
+ struct commit *commit = parents->item;
+ if (!(commit->object.flags & UNINTERESTING)) {
+ commit->object.flags |= UNINTERESTING;
+
+ /*
+ * Normally we haven't parsed the parent
+ * yet, so we won't have a parent of a parent
+ * here. However, it may turn out that we've
+ * reached this commit some other way (where it
+ * wasn't uninteresting), in which case we need
+ * to mark its parents recursively too..
+ */
+ if (commit->parents)
+ mark_parents_uninteresting(commit);
+ }
+
+ /*
+ * A missing commit is ok iff its parent is marked
+ * uninteresting.
+ *
+ * We just mark such a thing parsed, so that when
+ * it is popped next time around, we won't be trying
+ * to parse it and get an error.
+ */
+ if (!has_sha1_file(commit->object.sha1))
+ commit->object.parsed = 1;
+ parents = parents->next;
+ }
+}
+
+static void add_pending_object_with_mode(struct rev_info *revs, struct object *obj, const char *name, unsigned mode)
+{
+ if (revs->no_walk && (obj->flags & UNINTERESTING))
+ die("object ranges do not make sense when not walking revisions");
+ if (revs->reflog_info && obj->type == OBJ_COMMIT &&
+ add_reflog_for_walk(revs->reflog_info,
+ (struct commit *)obj, name))
+ return;
+ add_object_array_with_mode(obj, name, &revs->pending, mode);
+}
+
+void add_pending_object(struct rev_info *revs, struct object *obj, const char *name)
+{
+ add_pending_object_with_mode(revs, obj, name, S_IFINVALID);
+}
+
+void add_head_to_pending(struct rev_info *revs)
+{
+ unsigned char sha1[20];
+ struct object *obj;
+ if (get_sha1("HEAD", sha1))
+ return;
+ obj = parse_object(sha1);
+ if (!obj)
+ return;
+ add_pending_object(revs, obj, "HEAD");
+}
+
+static struct object *get_reference(struct rev_info *revs, const char *name, const unsigned char *sha1, unsigned int flags)
+{
+ struct object *object;
+
+ object = parse_object(sha1);
+ if (!object)
+ die("bad object %s", name);
+ object->flags |= flags;
+ return object;
+}
+
+static struct commit *handle_commit(struct rev_info *revs, struct object *object, const char *name)
+{
+ unsigned long flags = object->flags;
+
+ /*
+ * Tag object? Look what it points to..
+ */
+ while (object->type == OBJ_TAG) {
+ struct tag *tag = (struct tag *) object;
+ if (revs->tag_objects && !(flags & UNINTERESTING))
+ add_pending_object(revs, object, tag->tag);
+ object = parse_object(tag->tagged->sha1);
+ if (!object)
+ die("bad object %s", sha1_to_hex(tag->tagged->sha1));
+ }
+
+ /*
+ * Commit object? Just return it, we'll do all the complex
+ * reachability crud.
+ */
+ if (object->type == OBJ_COMMIT) {
+ struct commit *commit = (struct commit *)object;
+ if (parse_commit(commit) < 0)
+ die("unable to parse commit %s", name);
+ if (flags & UNINTERESTING) {
+ commit->object.flags |= UNINTERESTING;
+ mark_parents_uninteresting(commit);
+ revs->limited = 1;
+ }
+ return commit;
+ }
+
+ /*
+ * Tree object? Either mark it uniniteresting, or add it
+ * to the list of objects to look at later..
+ */
+ if (object->type == OBJ_TREE) {
+ struct tree *tree = (struct tree *)object;
+ if (!revs->tree_objects)
+ return NULL;
+ if (flags & UNINTERESTING) {
+ mark_tree_uninteresting(tree);
+ return NULL;
+ }
+ add_pending_object(revs, object, "");
+ return NULL;
+ }
+
+ /*
+ * Blob object? You know the drill by now..
+ */
+ if (object->type == OBJ_BLOB) {
+ struct blob *blob = (struct blob *)object;
+ if (!revs->blob_objects)
+ return NULL;
+ if (flags & UNINTERESTING) {
+ mark_blob_uninteresting(blob);
+ return NULL;
+ }
+ add_pending_object(revs, object, "");
+ return NULL;
+ }
+ die("%s is unknown object", name);
+}
+
+static int everybody_uninteresting(struct commit_list *orig)
+{
+ struct commit_list *list = orig;
+ while (list) {
+ struct commit *commit = list->item;
+ list = list->next;
+ if (commit->object.flags & UNINTERESTING)
+ continue;
+ return 0;
+ }
+ return 1;
+}
+
+/*
+ * The goal is to get REV_TREE_NEW as the result only if the
+ * diff consists of all '+' (and no other changes), and
+ * REV_TREE_DIFFERENT otherwise (of course if the trees are
+ * the same we want REV_TREE_SAME). That means that once we
+ * get to REV_TREE_DIFFERENT, we do not have to look any further.
+ */
+static int tree_difference = REV_TREE_SAME;
+
+static void file_add_remove(struct diff_options *options,
+ int addremove, unsigned mode,
+ const unsigned char *sha1,
+ const char *base, const char *path)
+{
+ int diff = REV_TREE_DIFFERENT;
+
+ /*
+ * Is it an add of a new file? It means that the old tree
+ * didn't have it at all, so we will turn "REV_TREE_SAME" ->
+ * "REV_TREE_NEW", but leave any "REV_TREE_DIFFERENT" alone
+ * (and if it already was "REV_TREE_NEW", we'll keep it
+ * "REV_TREE_NEW" of course).
+ */
+ if (addremove == '+') {
+ diff = tree_difference;
+ if (diff != REV_TREE_SAME)
+ return;
+ diff = REV_TREE_NEW;
+ }
+ tree_difference = diff;
+ if (tree_difference == REV_TREE_DIFFERENT)
+ DIFF_OPT_SET(options, HAS_CHANGES);
+}
+
+static void file_change(struct diff_options *options,
+ unsigned old_mode, unsigned new_mode,
+ const unsigned char *old_sha1,
+ const unsigned char *new_sha1,
+ const char *base, const char *path)
+{
+ tree_difference = REV_TREE_DIFFERENT;
+ DIFF_OPT_SET(options, HAS_CHANGES);
+}
+
+static int rev_compare_tree(struct rev_info *revs, struct tree *t1, struct tree *t2)
+{
+ if (!t1)
+ return REV_TREE_NEW;
+ if (!t2)
+ return REV_TREE_DIFFERENT;
+ tree_difference = REV_TREE_SAME;
+ DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
+ if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "",
+ &revs->pruning) < 0)
+ return REV_TREE_DIFFERENT;
+ return tree_difference;
+}
+
+static int rev_same_tree_as_empty(struct rev_info *revs, struct tree *t1)
+{
+ int retval;
+ void *tree;
+ unsigned long size;
+ struct tree_desc empty, real;
+
+ if (!t1)
+ return 0;
+
+ tree = read_object_with_reference(t1->object.sha1, tree_type, &size, NULL);
+ if (!tree)
+ return 0;
+ init_tree_desc(&real, tree, size);
+ init_tree_desc(&empty, "", 0);
+
+ tree_difference = REV_TREE_SAME;
+ DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
+ retval = diff_tree(&empty, &real, "", &revs->pruning);
+ free(tree);
+
+ return retval >= 0 && (tree_difference == REV_TREE_SAME);
+}
+
+static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
+{
+ struct commit_list **pp, *parent;
+ int tree_changed = 0, tree_same = 0;
+
+ /*
+ * If we don't do pruning, everything is interesting
+ */
+ if (!revs->prune)
+ return;
+
+ if (!commit->tree)
+ return;
+
+ if (!commit->parents) {
+ if (rev_same_tree_as_empty(revs, commit->tree))
+ commit->object.flags |= TREESAME;
+ return;
+ }
+
+ /*
+ * Normal non-merge commit? If we don't want to make the
+ * history dense, we consider it always to be a change..
+ */
+ if (!revs->dense && !commit->parents->next)
+ return;
+
+ pp = &commit->parents;
+ while ((parent = *pp) != NULL) {
+ struct commit *p = parent->item;
+
+ if (parse_commit(p) < 0)
+ die("cannot simplify commit %s (because of %s)",
+ sha1_to_hex(commit->object.sha1),
+ sha1_to_hex(p->object.sha1));
+ switch (rev_compare_tree(revs, p->tree, commit->tree)) {
+ case REV_TREE_SAME:
+ tree_same = 1;
+ if (!revs->simplify_history || (p->object.flags & UNINTERESTING)) {
+ /* Even if a merge with an uninteresting
+ * side branch brought the entire change
+ * we are interested in, we do not want
+ * to lose the other branches of this
+ * merge, so we just keep going.
+ */
+ pp = &parent->next;
+ continue;
+ }
+ parent->next = NULL;
+ commit->parents = parent;
+ commit->object.flags |= TREESAME;
+ return;
+
+ case REV_TREE_NEW:
+ if (revs->remove_empty_trees &&
+ rev_same_tree_as_empty(revs, p->tree)) {
+ /* We are adding all the specified
+ * paths from this parent, so the
+ * history beyond this parent is not
+ * interesting. Remove its parents
+ * (they are grandparents for us).
+ * IOW, we pretend this parent is a
+ * "root" commit.
+ */
+ if (parse_commit(p) < 0)
+ die("cannot simplify commit %s (invalid %s)",
+ sha1_to_hex(commit->object.sha1),
+ sha1_to_hex(p->object.sha1));
+ p->parents = NULL;
+ }
+ /* fallthrough */
+ case REV_TREE_DIFFERENT:
+ tree_changed = 1;
+ pp = &parent->next;
+ continue;
+ }
+ die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1));
+ }
+ if (tree_changed && !tree_same)
+ return;
+ commit->object.flags |= TREESAME;
+}
+
+static int add_parents_to_list(struct rev_info *revs, struct commit *commit, struct commit_list **list)
+{
+ struct commit_list *parent = commit->parents;
+ unsigned left_flag;
+ int add, rest;
+
+ if (commit->object.flags & ADDED)
+ return 0;
+ commit->object.flags |= ADDED;
+
+ /*
+ * If the commit is uninteresting, don't try to
+ * prune parents - we want the maximal uninteresting
+ * set.
+ *
+ * Normally we haven't parsed the parent
+ * yet, so we won't have a parent of a parent
+ * here. However, it may turn out that we've
+ * reached this commit some other way (where it
+ * wasn't uninteresting), in which case we need
+ * to mark its parents recursively too..
+ */
+ if (commit->object.flags & UNINTERESTING) {
+ while (parent) {
+ struct commit *p = parent->item;
+ parent = parent->next;
+ if (parse_commit(p) < 0)
+ return -1;
+ p->object.flags |= UNINTERESTING;
+ if (p->parents)
+ mark_parents_uninteresting(p);
+ if (p->object.flags & SEEN)
+ continue;
+ p->object.flags |= SEEN;
+ insert_by_date(p, list);
+ }
+ return 0;
+ }
+
+ /*
+ * Ok, the commit wasn't uninteresting. Try to
+ * simplify the commit history and find the parent
+ * that has no differences in the path set if one exists.
+ */
+ try_to_simplify_commit(revs, commit);
+
+ if (revs->no_walk)
+ return 0;
+
+ left_flag = (commit->object.flags & SYMMETRIC_LEFT);
+
+ rest = !revs->first_parent_only;
+ for (parent = commit->parents, add = 1; parent; add = rest) {
+ struct commit *p = parent->item;
+
+ parent = parent->next;
+ if (parse_commit(p) < 0)
+ return -1;
+ p->object.flags |= left_flag;
+ if (p->object.flags & SEEN)
+ continue;
+ p->object.flags |= SEEN;
+ if (add)
+ insert_by_date(p, list);
+ }
+ return 0;
+}
+
+static void cherry_pick_list(struct commit_list *list, struct rev_info *revs)
+{
+ struct commit_list *p;
+ int left_count = 0, right_count = 0;
+ int left_first;
+ struct patch_ids ids;
+
+ /* First count the commits on the left and on the right */
+ for (p = list; p; p = p->next) {
+ struct commit *commit = p->item;
+ unsigned flags = commit->object.flags;
+ if (flags & BOUNDARY)
+ ;
+ else if (flags & SYMMETRIC_LEFT)
+ left_count++;
+ else
+ right_count++;
+ }
+
+ left_first = left_count < right_count;
+ init_patch_ids(&ids);
+ if (revs->diffopt.nr_paths) {
+ ids.diffopts.nr_paths = revs->diffopt.nr_paths;
+ ids.diffopts.paths = revs->diffopt.paths;
+ ids.diffopts.pathlens = revs->diffopt.pathlens;
+ }
+
+ /* Compute patch-ids for one side */
+ for (p = list; p; p = p->next) {
+ struct commit *commit = p->item;
+ unsigned flags = commit->object.flags;
+
+ if (flags & BOUNDARY)
+ continue;
+ /*
+ * If we have fewer left, left_first is set and we omit
+ * commits on the right branch in this loop. If we have
+ * fewer right, we skip the left ones.
+ */
+ if (left_first != !!(flags & SYMMETRIC_LEFT))
+ continue;
+ commit->util = add_commit_patch_id(commit, &ids);
+ }
+
+ /* Check the other side */
+ for (p = list; p; p = p->next) {
+ struct commit *commit = p->item;
+ struct patch_id *id;
+ unsigned flags = commit->object.flags;
+
+ if (flags & BOUNDARY)
+ continue;
+ /*
+ * If we have fewer left, left_first is set and we omit
+ * commits on the left branch in this loop.
+ */
+ if (left_first == !!(flags & SYMMETRIC_LEFT))
+ continue;
+
+ /*
+ * Have we seen the same patch id?
+ */
+ id = has_commit_patch_id(commit, &ids);
+ if (!id)
+ continue;
+ id->seen = 1;
+ commit->object.flags |= SHOWN;
+ }
+
+ /* Now check the original side for seen ones */
+ for (p = list; p; p = p->next) {
+ struct commit *commit = p->item;
+ struct patch_id *ent;
+
+ ent = commit->util;
+ if (!ent)
+ continue;
+ if (ent->seen)
+ commit->object.flags |= SHOWN;
+ commit->util = NULL;
+ }
+
+ free_patch_ids(&ids);
+}
+
+static int limit_list(struct rev_info *revs)
+{
+ struct commit_list *list = revs->commits;
+ struct commit_list *newlist = NULL;
+ struct commit_list **p = &newlist;
+
+ while (list) {
+ struct commit_list *entry = list;
+ struct commit *commit = list->item;
+ struct object *obj = &commit->object;
+ show_early_output_fn_t show;
+
+ list = list->next;
+ free(entry);
+
+ if (revs->max_age != -1 && (commit->date < revs->max_age))
+ obj->flags |= UNINTERESTING;
+ if (add_parents_to_list(revs, commit, &list) < 0)
+ return -1;
+ if (obj->flags & UNINTERESTING) {
+ mark_parents_uninteresting(commit);
+ if (everybody_uninteresting(list))
+ break;
+ continue;
+ }
+ if (revs->min_age != -1 && (commit->date > revs->min_age))
+ continue;
+ p = &commit_list_insert(commit, p)->next;
+
+ show = show_early_output;
+ if (!show)
+ continue;
+
+ show(revs, newlist);
+ show_early_output = NULL;
+ }
+ if (revs->cherry_pick)
+ cherry_pick_list(newlist, revs);
+
+ revs->commits = newlist;
+ return 0;
+}
+
+struct all_refs_cb {
+ int all_flags;
+ int warned_bad_reflog;
+ struct rev_info *all_revs;
+ const char *name_for_errormsg;
+};
+
+static int handle_one_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
+{
+ struct all_refs_cb *cb = cb_data;
+ struct object *object = get_reference(cb->all_revs, path, sha1,
+ cb->all_flags);
+ add_pending_object(cb->all_revs, object, path);
+ return 0;
+}
+
+static void handle_all(struct rev_info *revs, unsigned flags)
+{
+ struct all_refs_cb cb;
+ cb.all_revs = revs;
+ cb.all_flags = flags;
+ for_each_ref(handle_one_ref, &cb);
+}
+
+static void handle_one_reflog_commit(unsigned char *sha1, void *cb_data)
+{
+ struct all_refs_cb *cb = cb_data;
+ if (!is_null_sha1(sha1)) {
+ struct object *o = parse_object(sha1);
+ if (o) {
+ o->flags |= cb->all_flags;
+ add_pending_object(cb->all_revs, o, "");
+ }
+ else if (!cb->warned_bad_reflog) {
+ warning("reflog of '%s' references pruned commits",
+ cb->name_for_errormsg);
+ cb->warned_bad_reflog = 1;
+ }
+ }
+}
+
+static int handle_one_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
+ const char *email, unsigned long timestamp, int tz,
+ const char *message, void *cb_data)
+{
+ handle_one_reflog_commit(osha1, cb_data);
+ handle_one_reflog_commit(nsha1, cb_data);
+ return 0;
+}
+
+static int handle_one_reflog(const char *path, const unsigned char *sha1, int flag, void *cb_data)
+{
+ struct all_refs_cb *cb = cb_data;
+ cb->warned_bad_reflog = 0;
+ cb->name_for_errormsg = path;
+ for_each_reflog_ent(path, handle_one_reflog_ent, cb_data);
+ return 0;
+}
+
+static void handle_reflog(struct rev_info *revs, unsigned flags)
+{
+ struct all_refs_cb cb;
+ cb.all_revs = revs;
+ cb.all_flags = flags;
+ for_each_reflog(handle_one_reflog, &cb);
+}
+
+static int add_parents_only(struct rev_info *revs, const char *arg, int flags)
+{
+ unsigned char sha1[20];
+ struct object *it;
+ struct commit *commit;
+ struct commit_list *parents;
+
+ if (*arg == '^') {
+ flags ^= UNINTERESTING;
+ arg++;
+ }
+ if (get_sha1(arg, sha1))
+ return 0;
+ while (1) {
+ it = get_reference(revs, arg, sha1, 0);
+ if (it->type != OBJ_TAG)
+ break;
+ hashcpy(sha1, ((struct tag*)it)->tagged->sha1);
+ }
+ if (it->type != OBJ_COMMIT)
+ return 0;
+ commit = (struct commit *)it;
+ for (parents = commit->parents; parents; parents = parents->next) {
+ it = &parents->item->object;
+ it->flags |= flags;
+ add_pending_object(revs, it, arg);
+ }
+ return 1;
+}
+
+void init_revisions(struct rev_info *revs, const char *prefix)
+{
+ memset(revs, 0, sizeof(*revs));
+
+ revs->abbrev = DEFAULT_ABBREV;
+ revs->ignore_merges = 1;
+ revs->simplify_history = 1;
+ DIFF_OPT_SET(&revs->pruning, RECURSIVE);
+ DIFF_OPT_SET(&revs->pruning, QUIET);
+ revs->pruning.add_remove = file_add_remove;
+ revs->pruning.change = file_change;
+ revs->lifo = 1;
+ revs->dense = 1;
+ revs->prefix = prefix;
+ revs->max_age = -1;
+ revs->min_age = -1;
+ revs->skip_count = -1;
+ revs->max_count = -1;
+
+ revs->commit_format = CMIT_FMT_DEFAULT;
+
+ diff_setup(&revs->diffopt);
+}
+
+static void add_pending_commit_list(struct rev_info *revs,
+ struct commit_list *commit_list,
+ unsigned int flags)
+{
+ while (commit_list) {
+ struct object *object = &commit_list->item->object;
+ object->flags |= flags;
+ add_pending_object(revs, object, sha1_to_hex(object->sha1));
+ commit_list = commit_list->next;
+ }
+}
+
+static void prepare_show_merge(struct rev_info *revs)
+{
+ struct commit_list *bases;
+ struct commit *head, *other;
+ unsigned char sha1[20];
+ const char **prune = NULL;
+ int i, prune_num = 1; /* counting terminating NULL */
+
+ if (get_sha1("HEAD", sha1) || !(head = lookup_commit(sha1)))
+ die("--merge without HEAD?");
+ if (get_sha1("MERGE_HEAD", sha1) || !(other = lookup_commit(sha1)))
+ die("--merge without MERGE_HEAD?");
+ add_pending_object(revs, &head->object, "HEAD");
+ add_pending_object(revs, &other->object, "MERGE_HEAD");
+ bases = get_merge_bases(head, other, 1);
+ while (bases) {
+ struct commit *it = bases->item;
+ struct commit_list *n = bases->next;
+ free(bases);
+ bases = n;
+ it->object.flags |= UNINTERESTING;
+ add_pending_object(revs, &it->object, "(merge-base)");
+ }
+
+ if (!active_nr)
+ read_cache();
+ for (i = 0; i < active_nr; i++) {
+ struct cache_entry *ce = active_cache[i];
+ if (!ce_stage(ce))
+ continue;
+ if (ce_path_match(ce, revs->prune_data)) {
+ prune_num++;
+ prune = xrealloc(prune, sizeof(*prune) * prune_num);
+ prune[prune_num-2] = ce->name;
+ prune[prune_num-1] = NULL;
+ }
+ while ((i+1 < active_nr) &&
+ ce_same_name(ce, active_cache[i+1]))
+ i++;
+ }
+ revs->prune_data = prune;
+}
+
+int handle_revision_arg(const char *arg, struct rev_info *revs,
+ int flags,
+ int cant_be_filename)
+{
+ unsigned mode;
+ char *dotdot;
+ struct object *object;
+ unsigned char sha1[20];
+ int local_flags;
+
+ dotdot = strstr(arg, "..");
+ if (dotdot) {
+ unsigned char from_sha1[20];
+ const char *next = dotdot + 2;
+ const char *this = arg;
+ int symmetric = *next == '.';
+ unsigned int flags_exclude = flags ^ UNINTERESTING;
+
+ *dotdot = 0;
+ next += symmetric;
+
+ if (!*next)
+ next = "HEAD";
+ if (dotdot == arg)
+ this = "HEAD";
+ if (!get_sha1(this, from_sha1) &&
+ !get_sha1(next, sha1)) {
+ struct commit *a, *b;
+ struct commit_list *exclude;
+
+ a = lookup_commit_reference(from_sha1);
+ b = lookup_commit_reference(sha1);
+ if (!a || !b) {
+ die(symmetric ?
+ "Invalid symmetric difference expression %s...%s" :
+ "Invalid revision range %s..%s",
+ arg, next);
+ }
+
+ if (!cant_be_filename) {
+ *dotdot = '.';
+ verify_non_filename(revs->prefix, arg);
+ }
+
+ if (symmetric) {
+ exclude = get_merge_bases(a, b, 1);
+ add_pending_commit_list(revs, exclude,
+ flags_exclude);
+ free_commit_list(exclude);
+ a->object.flags |= flags | SYMMETRIC_LEFT;
+ } else
+ a->object.flags |= flags_exclude;
+ b->object.flags |= flags;
+ add_pending_object(revs, &a->object, this);
+ add_pending_object(revs, &b->object, next);
+ return 0;
+ }
+ *dotdot = '.';
+ }
+ dotdot = strstr(arg, "^@");
+ if (dotdot && !dotdot[2]) {
+ *dotdot = 0;
+ if (add_parents_only(revs, arg, flags))
+ return 0;
+ *dotdot = '^';
+ }
+ dotdot = strstr(arg, "^!");
+ if (dotdot && !dotdot[2]) {
+ *dotdot = 0;
+ if (!add_parents_only(revs, arg, flags ^ UNINTERESTING))
+ *dotdot = '^';
+ }
+
+ local_flags = 0;
+ if (*arg == '^') {
+ local_flags = UNINTERESTING;
+ arg++;
+ }
+ if (get_sha1_with_mode(arg, sha1, &mode))
+ return -1;
+ if (!cant_be_filename)
+ verify_non_filename(revs->prefix, arg);
+ object = get_reference(revs, arg, sha1, flags ^ local_flags);
+ add_pending_object_with_mode(revs, object, arg, mode);
+ return 0;
+}
+
+static void add_grep(struct rev_info *revs, const char *ptn, enum grep_pat_token what)
+{
+ if (!revs->grep_filter) {
+ struct grep_opt *opt = xcalloc(1, sizeof(*opt));
+ opt->status_only = 1;
+ opt->pattern_tail = &(opt->pattern_list);
+ opt->regflags = REG_NEWLINE;
+ revs->grep_filter = opt;
+ }
+ append_grep_pattern(revs->grep_filter, ptn,
+ "command line", 0, what);
+}
+
+static void add_header_grep(struct rev_info *revs, const char *field, const char *pattern)
+{
+ char *pat;
+ const char *prefix;
+ int patlen, fldlen;
+
+ fldlen = strlen(field);
+ patlen = strlen(pattern);
+ pat = xmalloc(patlen + fldlen + 10);
+ prefix = ".*";
+ if (*pattern == '^') {
+ prefix = "";
+ pattern++;
+ }
+ sprintf(pat, "^%s %s%s", field, prefix, pattern);
+ add_grep(revs, pat, GREP_PATTERN_HEAD);
+}
+
+static void add_message_grep(struct rev_info *revs, const char *pattern)
+{
+ add_grep(revs, pattern, GREP_PATTERN_BODY);
+}
+
+static void add_ignore_packed(struct rev_info *revs, const char *name)
+{
+ int num = ++revs->num_ignore_packed;
+
+ revs->ignore_packed = xrealloc(revs->ignore_packed,
+ sizeof(const char **) * (num + 1));
+ revs->ignore_packed[num-1] = name;
+ revs->ignore_packed[num] = NULL;
+}
+
+/*
+ * Parse revision information, filling in the "rev_info" structure,
+ * and removing the used arguments from the argument list.
+ *
+ * Returns the number of arguments left that weren't recognized
+ * (which are also moved to the head of the argument list)
+ */
+int setup_revisions(int argc, const char **argv, struct rev_info *revs, const char *def)
+{
+ int i, flags, seen_dashdash, show_merge;
+ const char **unrecognized = argv + 1;
+ int left = 1;
+ int all_match = 0;
+ int regflags = 0;
+
+ /* First, search for "--" */
+ seen_dashdash = 0;
+ for (i = 1; i < argc; i++) {
+ const char *arg = argv[i];
+ if (strcmp(arg, "--"))
+ continue;
+ argv[i] = NULL;
+ argc = i;
+ if (argv[i + 1])
+ revs->prune_data = get_pathspec(revs->prefix, argv + i + 1);
+ seen_dashdash = 1;
+ break;
+ }
+
+ flags = show_merge = 0;
+ for (i = 1; i < argc; i++) {
+ const char *arg = argv[i];
+ if (*arg == '-') {
+ int opts;
+ if (!prefixcmp(arg, "--max-count=")) {
+ revs->max_count = atoi(arg + 12);
+ continue;
+ }
+ if (!prefixcmp(arg, "--skip=")) {
+ revs->skip_count = atoi(arg + 7);
+ continue;
+ }
+ /* accept -<digit>, like traditional "head" */
+ if ((*arg == '-') && isdigit(arg[1])) {
+ revs->max_count = atoi(arg + 1);
+ continue;
+ }
+ if (!strcmp(arg, "-n")) {
+ if (argc <= i + 1)
+ die("-n requires an argument");
+ revs->max_count = atoi(argv[++i]);
+ continue;
+ }
+ if (!prefixcmp(arg, "-n")) {
+ revs->max_count = atoi(arg + 2);
+ continue;
+ }
+ if (!prefixcmp(arg, "--max-age=")) {
+ revs->max_age = atoi(arg + 10);
+ continue;
+ }
+ if (!prefixcmp(arg, "--since=")) {
+ revs->max_age = approxidate(arg + 8);
+ continue;
+ }
+ if (!prefixcmp(arg, "--after=")) {
+ revs->max_age = approxidate(arg + 8);
+ continue;
+ }
+ if (!prefixcmp(arg, "--min-age=")) {
+ revs->min_age = atoi(arg + 10);
+ continue;
+ }
+ if (!prefixcmp(arg, "--before=")) {
+ revs->min_age = approxidate(arg + 9);
+ continue;
+ }
+ if (!prefixcmp(arg, "--until=")) {
+ revs->min_age = approxidate(arg + 8);
+ continue;
+ }
+ if (!strcmp(arg, "--all")) {
+ handle_all(revs, flags);
+ continue;
+ }
+ if (!strcmp(arg, "--first-parent")) {
+ revs->first_parent_only = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--reflog")) {
+ handle_reflog(revs, flags);
+ continue;
+ }
+ if (!strcmp(arg, "-g") ||
+ !strcmp(arg, "--walk-reflogs")) {
+ init_reflog_walk(&revs->reflog_info);
+ continue;
+ }
+ if (!strcmp(arg, "--not")) {
+ flags ^= UNINTERESTING;
+ continue;
+ }
+ if (!strcmp(arg, "--default")) {
+ if (++i >= argc)
+ die("bad --default argument");
+ def = argv[i];
+ continue;
+ }
+ if (!strcmp(arg, "--merge")) {
+ show_merge = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--topo-order")) {
+ revs->topo_order = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--date-order")) {
+ revs->lifo = 0;
+ revs->topo_order = 1;
+ continue;
+ }
+ if (!prefixcmp(arg, "--early-output")) {
+ int count = 100;
+ switch (arg[14]) {
+ case '=':
+ count = atoi(arg+15);
+ /* Fallthrough */
+ case 0:
+ revs->topo_order = 1;
+ revs->early_output = count;
+ continue;
+ }
+ }
+ if (!strcmp(arg, "--parents")) {
+ revs->parents = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--dense")) {
+ revs->dense = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--sparse")) {
+ revs->dense = 0;
+ continue;
+ }
+ if (!strcmp(arg, "--remove-empty")) {
+ revs->remove_empty_trees = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--no-merges")) {
+ revs->no_merges = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--boundary")) {
+ revs->boundary = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--left-right")) {
+ revs->left_right = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--cherry-pick")) {
+ revs->cherry_pick = 1;
+ revs->limited = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--objects")) {
+ revs->tag_objects = 1;
+ revs->tree_objects = 1;
+ revs->blob_objects = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--objects-edge")) {
+ revs->tag_objects = 1;
+ revs->tree_objects = 1;
+ revs->blob_objects = 1;
+ revs->edge_hint = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--unpacked")) {
+ revs->unpacked = 1;
+ free(revs->ignore_packed);
+ revs->ignore_packed = NULL;
+ revs->num_ignore_packed = 0;
+ continue;
+ }
+ if (!prefixcmp(arg, "--unpacked=")) {
+ revs->unpacked = 1;
+ add_ignore_packed(revs, arg+11);
+ continue;
+ }
+ if (!strcmp(arg, "-r")) {
+ revs->diff = 1;
+ DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
+ continue;
+ }
+ if (!strcmp(arg, "-t")) {
+ revs->diff = 1;
+ DIFF_OPT_SET(&revs->diffopt, RECURSIVE);
+ DIFF_OPT_SET(&revs->diffopt, TREE_IN_RECURSIVE);
+ continue;
+ }
+ if (!strcmp(arg, "-m")) {
+ revs->ignore_merges = 0;
+ continue;
+ }
+ if (!strcmp(arg, "-c")) {
+ revs->diff = 1;
+ revs->dense_combined_merges = 0;
+ revs->combine_merges = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--cc")) {
+ revs->diff = 1;
+ revs->dense_combined_merges = 1;
+ revs->combine_merges = 1;
+ continue;
+ }
+ if (!strcmp(arg, "-v")) {
+ revs->verbose_header = 1;
+ continue;
+ }
+ if (!prefixcmp(arg, "--pretty")) {
+ revs->verbose_header = 1;
+ revs->commit_format = get_commit_format(arg+8);
+ continue;
+ }
+ if (!strcmp(arg, "--root")) {
+ revs->show_root_diff = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--no-commit-id")) {
+ revs->no_commit_id = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--always")) {
+ revs->always_show_header = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--no-abbrev")) {
+ revs->abbrev = 0;
+ continue;
+ }
+ if (!strcmp(arg, "--abbrev")) {
+ revs->abbrev = DEFAULT_ABBREV;
+ continue;
+ }
+ if (!prefixcmp(arg, "--abbrev=")) {
+ revs->abbrev = strtoul(arg + 9, NULL, 10);
+ if (revs->abbrev < MINIMUM_ABBREV)
+ revs->abbrev = MINIMUM_ABBREV;
+ else if (revs->abbrev > 40)
+ revs->abbrev = 40;
+ continue;
+ }
+ if (!strcmp(arg, "--abbrev-commit")) {
+ revs->abbrev_commit = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--full-diff")) {
+ revs->diff = 1;
+ revs->full_diff = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--full-history")) {
+ revs->simplify_history = 0;
+ continue;
+ }
+ if (!strcmp(arg, "--relative-date")) {
+ revs->date_mode = DATE_RELATIVE;
+ continue;
+ }
+ if (!strncmp(arg, "--date=", 7)) {
+ revs->date_mode = parse_date_format(arg + 7);
+ continue;
+ }
+ if (!strcmp(arg, "--log-size")) {
+ revs->show_log_size = 1;
+ continue;
+ }
+
+ /*
+ * Grepping the commit log
+ */
+ if (!prefixcmp(arg, "--author=")) {
+ add_header_grep(revs, "author", arg+9);
+ continue;
+ }
+ if (!prefixcmp(arg, "--committer=")) {
+ add_header_grep(revs, "committer", arg+12);
+ continue;
+ }
+ if (!prefixcmp(arg, "--grep=")) {
+ add_message_grep(revs, arg+7);
+ continue;
+ }
+ if (!strcmp(arg, "--extended-regexp") ||
+ !strcmp(arg, "-E")) {
+ regflags |= REG_EXTENDED;
+ continue;
+ }
+ if (!strcmp(arg, "--regexp-ignore-case") ||
+ !strcmp(arg, "-i")) {
+ regflags |= REG_ICASE;
+ continue;
+ }
+ if (!strcmp(arg, "--all-match")) {
+ all_match = 1;
+ continue;
+ }
+ if (!prefixcmp(arg, "--encoding=")) {
+ arg += 11;
+ if (strcmp(arg, "none"))
+ git_log_output_encoding = xstrdup(arg);
+ else
+ git_log_output_encoding = "";
+ continue;
+ }
+ if (!strcmp(arg, "--reverse")) {
+ revs->reverse ^= 1;
+ continue;
+ }
+ if (!strcmp(arg, "--no-walk")) {
+ revs->no_walk = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--do-walk")) {
+ revs->no_walk = 0;
+ continue;
+ }
+
+ opts = diff_opt_parse(&revs->diffopt, argv+i, argc-i);
+ if (opts > 0) {
+ i += opts - 1;
+ continue;
+ }
+ *unrecognized++ = arg;
+ left++;
+ continue;
+ }
+
+ if (handle_revision_arg(arg, revs, flags, seen_dashdash)) {
+ int j;
+ if (seen_dashdash || *arg == '^')
+ die("bad revision '%s'", arg);
+
+ /* If we didn't have a "--":
+ * (1) all filenames must exist;
+ * (2) all rev-args must not be interpretable
+ * as a valid filename.
+ * but the latter we have checked in the main loop.
+ */
+ for (j = i; j < argc; j++)
+ verify_filename(revs->prefix, argv[j]);
+
+ revs->prune_data = get_pathspec(revs->prefix,
+ argv + i);
+ break;
+ }
+ }
+
+ if (revs->grep_filter)
+ revs->grep_filter->regflags |= regflags;
+
+ if (show_merge)
+ prepare_show_merge(revs);
+ if (def && !revs->pending.nr) {
+ unsigned char sha1[20];
+ struct object *object;
+ unsigned mode;
+ if (get_sha1_with_mode(def, sha1, &mode))
+ die("bad default revision '%s'", def);
+ object = get_reference(revs, def, sha1, 0);
+ add_pending_object_with_mode(revs, object, def, mode);
+ }
+
+ /* Did the user ask for any diff output? Run the diff! */
+ if (revs->diffopt.output_format & ~DIFF_FORMAT_NO_OUTPUT)
+ revs->diff = 1;
+
+ /* Pickaxe, diff-filter and rename following need diffs */
+ if (revs->diffopt.pickaxe ||
+ revs->diffopt.filter ||
+ DIFF_OPT_TST(&revs->diffopt, FOLLOW_RENAMES))
+ revs->diff = 1;
+
+ if (revs->topo_order)
+ revs->limited = 1;
+
+ if (revs->prune_data) {
+ diff_tree_setup_paths(revs->prune_data, &revs->pruning);
+ /* Can't prune commits with rename following: the paths change.. */
+ if (!DIFF_OPT_TST(&revs->diffopt, FOLLOW_RENAMES))
+ revs->prune = 1;
+ if (!revs->full_diff)
+ diff_tree_setup_paths(revs->prune_data, &revs->diffopt);
+ }
+ if (revs->combine_merges) {
+ revs->ignore_merges = 0;
+ if (revs->dense_combined_merges && !revs->diffopt.output_format)
+ revs->diffopt.output_format = DIFF_FORMAT_PATCH;
+ }
+ revs->diffopt.abbrev = revs->abbrev;
+ if (diff_setup_done(&revs->diffopt) < 0)
+ die("diff_setup_done failed");
+
+ if (revs->grep_filter) {
+ revs->grep_filter->all_match = all_match;
+ compile_grep_patterns(revs->grep_filter);
+ }
+
+ if (revs->reverse && revs->reflog_info)
+ die("cannot combine --reverse with --walk-reflogs");
+
+ return left;
+}
+
+int prepare_revision_walk(struct rev_info *revs)
+{
+ int nr = revs->pending.nr;
+ struct object_array_entry *e, *list;
+
+ e = list = revs->pending.objects;
+ revs->pending.nr = 0;
+ revs->pending.alloc = 0;
+ revs->pending.objects = NULL;
+ while (--nr >= 0) {
+ struct commit *commit = handle_commit(revs, e->item, e->name);
+ if (commit) {
+ if (!(commit->object.flags & SEEN)) {
+ commit->object.flags |= SEEN;
+ insert_by_date(commit, &revs->commits);
+ }
+ }
+ e++;
+ }
+ free(list);
+
+ if (revs->no_walk)
+ return 0;
+ if (revs->limited)
+ if (limit_list(revs) < 0)
+ return -1;
+ if (revs->topo_order)
+ sort_in_topological_order(&revs->commits, revs->lifo);
+ return 0;
+}
+
+enum rewrite_result {
+ rewrite_one_ok,
+ rewrite_one_noparents,
+ rewrite_one_error,
+};
+
+static enum rewrite_result rewrite_one(struct rev_info *revs, struct commit **pp)
+{
+ for (;;) {
+ struct commit *p = *pp;
+ if (!revs->limited)
+ if (add_parents_to_list(revs, p, &revs->commits) < 0)
+ return rewrite_one_error;
+ if (p->parents && p->parents->next)
+ return rewrite_one_ok;
+ if (p->object.flags & UNINTERESTING)
+ return rewrite_one_ok;
+ if (!(p->object.flags & TREESAME))
+ return rewrite_one_ok;
+ if (!p->parents)
+ return rewrite_one_noparents;
+ *pp = p->parents->item;
+ }
+}
+
+static void remove_duplicate_parents(struct commit *commit)
+{
+ struct commit_list **pp, *p;
+
+ /* Examine existing parents while marking ones we have seen... */
+ pp = &commit->parents;
+ while ((p = *pp) != NULL) {
+ struct commit *parent = p->item;
+ if (parent->object.flags & TMP_MARK) {
+ *pp = p->next;
+ continue;
+ }
+ parent->object.flags |= TMP_MARK;
+ pp = &p->next;
+ }
+ /* ... and clear the temporary mark */
+ for (p = commit->parents; p; p = p->next)
+ p->item->object.flags &= ~TMP_MARK;
+}
+
+static int rewrite_parents(struct rev_info *revs, struct commit *commit)
+{
+ struct commit_list **pp = &commit->parents;
+ while (*pp) {
+ struct commit_list *parent = *pp;
+ switch (rewrite_one(revs, &parent->item)) {
+ case rewrite_one_ok:
+ break;
+ case rewrite_one_noparents:
+ *pp = parent->next;
+ continue;
+ case rewrite_one_error:
+ return -1;
+ }
+ pp = &parent->next;
+ }
+ remove_duplicate_parents(commit);
+ return 0;
+}
+
+static int commit_match(struct commit *commit, struct rev_info *opt)
+{
+ if (!opt->grep_filter)
+ return 1;
+ return grep_buffer(opt->grep_filter,
+ NULL, /* we say nothing, not even filename */
+ commit->buffer, strlen(commit->buffer));
+}
+
+enum commit_action simplify_commit(struct rev_info *revs, struct commit *commit)
+{
+ if (commit->object.flags & SHOWN)
+ return commit_ignore;
+ if (revs->unpacked && has_sha1_pack(commit->object.sha1, revs->ignore_packed))
+ return commit_ignore;
+ if (commit->object.flags & UNINTERESTING)
+ return commit_ignore;
+ if (revs->min_age != -1 && (commit->date > revs->min_age))
+ return commit_ignore;
+ if (revs->no_merges && commit->parents && commit->parents->next)
+ return commit_ignore;
+ if (!commit_match(commit, revs))
+ return commit_ignore;
+ if (revs->prune && revs->dense) {
+ /* Commit without changes? */
+ if (commit->object.flags & TREESAME) {
+ /* drop merges unless we want parenthood */
+ if (!revs->parents)
+ return commit_ignore;
+ /* non-merge - always ignore it */
+ if (!commit->parents || !commit->parents->next)
+ return commit_ignore;
+ }
+ if (revs->parents && rewrite_parents(revs, commit) < 0)
+ return commit_error;
+ }
+ return commit_show;
+}
+
+static struct commit *get_revision_1(struct rev_info *revs)
+{
+ if (!revs->commits)
+ return NULL;
+
+ do {
+ struct commit_list *entry = revs->commits;
+ struct commit *commit = entry->item;
+
+ revs->commits = entry->next;
+ free(entry);
+
+ if (revs->reflog_info)
+ fake_reflog_parent(revs->reflog_info, commit);
+
+ /*
+ * If we haven't done the list limiting, we need to look at
+ * the parents here. We also need to do the date-based limiting
+ * that we'd otherwise have done in limit_list().
+ */
+ if (!revs->limited) {
+ if (revs->max_age != -1 &&
+ (commit->date < revs->max_age))
+ continue;
+ if (add_parents_to_list(revs, commit, &revs->commits) < 0)
+ return NULL;
+ }
+
+ switch (simplify_commit(revs, commit)) {
+ case commit_ignore:
+ continue;
+ case commit_error:
+ return NULL;
+ default:
+ return commit;
+ }
+ } while (revs->commits);
+ return NULL;
+}
+
+static void gc_boundary(struct object_array *array)
+{
+ unsigned nr = array->nr;
+ unsigned alloc = array->alloc;
+ struct object_array_entry *objects = array->objects;
+
+ if (alloc <= nr) {
+ unsigned i, j;
+ for (i = j = 0; i < nr; i++) {
+ if (objects[i].item->flags & SHOWN)
+ continue;
+ if (i != j)
+ objects[j] = objects[i];
+ j++;
+ }
+ for (i = j; i < nr; i++)
+ objects[i].item = NULL;
+ array->nr = j;
+ }
+}
+
+struct commit *get_revision(struct rev_info *revs)
+{
+ struct commit *c = NULL;
+ struct commit_list *l;
+
+ if (revs->boundary == 2) {
+ unsigned i;
+ struct object_array *array = &revs->boundary_commits;
+ struct object_array_entry *objects = array->objects;
+ for (i = 0; i < array->nr; i++) {
+ c = (struct commit *)(objects[i].item);
+ if (!c)
+ continue;
+ if (!(c->object.flags & CHILD_SHOWN))
+ continue;
+ if (!(c->object.flags & SHOWN))
+ break;
+ }
+ if (array->nr <= i)
+ return NULL;
+
+ c->object.flags |= SHOWN | BOUNDARY;
+ return c;
+ }
+
+ if (revs->reverse) {
+ int limit = -1;
+
+ if (0 <= revs->max_count) {
+ limit = revs->max_count;
+ if (0 < revs->skip_count)
+ limit += revs->skip_count;
+ }
+ l = NULL;
+ while ((c = get_revision_1(revs))) {
+ commit_list_insert(c, &l);
+ if ((0 < limit) && !--limit)
+ break;
+ }
+ revs->commits = l;
+ revs->reverse = 0;
+ revs->max_count = -1;
+ c = NULL;
+ }
+
+ /*
+ * Now pick up what they want to give us
+ */
+ c = get_revision_1(revs);
+ if (c) {
+ while (0 < revs->skip_count) {
+ revs->skip_count--;
+ c = get_revision_1(revs);
+ if (!c)
+ break;
+ }
+ }
+
+ /*
+ * Check the max_count.
+ */
+ switch (revs->max_count) {
+ case -1:
+ break;
+ case 0:
+ c = NULL;
+ break;
+ default:
+ revs->max_count--;
+ }
+
+ if (c)
+ c->object.flags |= SHOWN;
+
+ if (!revs->boundary) {
+ return c;
+ }
+
+ if (!c) {
+ /*
+ * get_revision_1() runs out the commits, and
+ * we are done computing the boundaries.
+ * switch to boundary commits output mode.
+ */
+ revs->boundary = 2;
+ return get_revision(revs);
+ }
+
+ /*
+ * boundary commits are the commits that are parents of the
+ * ones we got from get_revision_1() but they themselves are
+ * not returned from get_revision_1(). Before returning
+ * 'c', we need to mark its parents that they could be boundaries.
+ */
+
+ for (l = c->parents; l; l = l->next) {
+ struct object *p;
+ p = &(l->item->object);
+ if (p->flags & (CHILD_SHOWN | SHOWN))
+ continue;
+ p->flags |= CHILD_SHOWN;
+ gc_boundary(&revs->boundary_commits);
+ add_object_array(p, NULL, &revs->boundary_commits);
+ }
+
+ return c;
+}