merge(3p/git): Merge git subtree at v2.29.2 r/1890

This also bumps the stable nixpkgs to 20.09 as of 2020-11-21, because
there is some breakage in the git build related to the netrc
credentials helper which someone has taken care of in nixpkgs.

The stable channel is not used for anything other than git, so this
should be fine.

Change-Id: I3575a19dab09e1e9556cf8231d717de9890484fb

1 files changed, 105 insertions, 30 deletions

diff --git a/third_party/git/builtin/rev-list.c b/third_party/git/builtin/rev-list.c
index 301ccb970bb3..25c6c3b38d4b 100644
--- a/third_party/git/builtin/rev-list.c
+++ b/third_party/git/builtin/rev-list.c
@@ -18,7 +18,6 @@
 #include "reflog-walk.h"
 #include "oidset.h"
 #include "packfile.h"
-#include "object-store.h"
 
 static const char rev_list_usage[] =
 "git rev-list [OPTION] <commit-id>... [ -- paths... ]\n"
@@ -254,11 +253,26 @@ static int finish_object(struct object *obj, const char *name, void *cb_data)
 static void show_object(struct object *obj, const char *name, void *cb_data)
 {
 	struct rev_list_info *info = cb_data;
+	struct rev_info *revs = info->revs;
+
 	if (finish_object(obj, name, cb_data))
 		return;
 	display_progress(progress, ++progress_counter);
 	if (info->flags & REV_LIST_QUIET)
 		return;
+
+	if (revs->count) {
+		/*
+		 * The object count is always accumulated in the .count_right
+		 * field for traversal that is not a left-right traversal,
+		 * and cmd_rev_list() made sure that a .count request that
+		 * wants to count non-commit objects, which is handled by
+		 * the show_object() callback, does not ask for .left_right.
+		 */
+		revs->count_right++;
+		return;
+	}
+
 	if (arg_show_object_names)
 		show_object_with_name(stdout, obj, name);
 	else
@@ -365,6 +379,79 @@ static inline int parse_missing_action_value(const char *value)
 	return 0;
 }
 
+static int try_bitmap_count(struct rev_info *revs,
+			    struct list_objects_filter_options *filter)
+{
+	uint32_t commit_count = 0,
+		 tag_count = 0,
+		 tree_count = 0,
+		 blob_count = 0;
+	int max_count;
+	struct bitmap_index *bitmap_git;
+
+	/* This function only handles counting, not general traversal. */
+	if (!revs->count)
+		return -1;
+
+	/*
+	 * A bitmap result can't know left/right, etc, because we don't
+	 * actually traverse.
+	 */
+	if (revs->left_right || revs->cherry_mark)
+		return -1;
+
+	/*
+	 * If we're counting reachable objects, we can't handle a max count of
+	 * commits to traverse, since we don't know which objects go with which
+	 * commit.
+	 */
+	if (revs->max_count >= 0 &&
+	    (revs->tag_objects || revs->tree_objects || revs->blob_objects))
+		return -1;
+
+	/*
+	 * This must be saved before doing any walking, since the revision
+	 * machinery will count it down to zero while traversing.
+	 */
+	max_count = revs->max_count;
+
+	bitmap_git = prepare_bitmap_walk(revs, filter);
+	if (!bitmap_git)
+		return -1;
+
+	count_bitmap_commit_list(bitmap_git, &commit_count,
+				 revs->tree_objects ? &tree_count : NULL,
+				 revs->blob_objects ? &blob_count : NULL,
+				 revs->tag_objects ? &tag_count : NULL);
+	if (max_count >= 0 && max_count < commit_count)
+		commit_count = max_count;
+
+	printf("%d\n", commit_count + tree_count + blob_count + tag_count);
+	free_bitmap_index(bitmap_git);
+	return 0;
+}
+
+static int try_bitmap_traversal(struct rev_info *revs,
+				struct list_objects_filter_options *filter)
+{
+	struct bitmap_index *bitmap_git;
+
+	/*
+	 * We can't use a bitmap result with a traversal limit, since the set
+	 * of commits we'd get would be essentially random.
+	 */
+	if (revs->max_count >= 0)
+		return -1;
+
+	bitmap_git = prepare_bitmap_walk(revs, filter);
+	if (!bitmap_git)
+		return -1;
+
+	traverse_bitmap_commit_list(bitmap_git, revs, &show_object_fast);
+	free_bitmap_index(bitmap_git);
+	return 0;
+}
+
 int cmd_rev_list(int argc, const char **argv, const char *prefix)
 {
 	struct rev_info revs;
@@ -471,10 +558,6 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix)
 			parse_list_objects_filter(&filter_options, arg);
 			if (filter_options.choice && !revs.blob_objects)
 				die(_("object filtering requires --objects"));
-			if (filter_options.choice == LOFC_SPARSE_OID &&
-			    !filter_options.sparse_oid_value)
-				die(_("invalid sparse value '%s'"),
-				    filter_options.filter_spec);
 			continue;
 		}
 		if (!strcmp(arg, ("--no-" CL_ARG__FILTER))) {
@@ -526,8 +609,10 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix)
 	if (revs.show_notes)
 		die(_("rev-list does not support display of notes"));
 
-	if (filter_options.choice && use_bitmap_index)
-		die(_("cannot combine --use-bitmap-index with object filtering"));
+	if (revs.count &&
+	    (revs.tag_objects || revs.tree_objects || revs.blob_objects) &&
+	    (revs.left_right || revs.cherry_mark))
+		die(_("marked counting is incompatible with --objects"));
 
 	save_commit_buffer = (revs.verbose_header ||
 			      revs.grep_filter.pattern_list ||
@@ -538,28 +623,11 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix)
 	if (show_progress)
 		progress = start_delayed_progress(show_progress, 0);
 
-	if (use_bitmap_index && !revs.prune) {
-		if (revs.count && !revs.left_right && !revs.cherry_mark) {
-			uint32_t commit_count;
-			int max_count = revs.max_count;
-			struct bitmap_index *bitmap_git;
-			if ((bitmap_git = prepare_bitmap_walk(&revs))) {
-				count_bitmap_commit_list(bitmap_git, &commit_count, NULL, NULL, NULL);
-				if (max_count >= 0 && max_count < commit_count)
-					commit_count = max_count;
-				printf("%d\n", commit_count);
-				free_bitmap_index(bitmap_git);
-				return 0;
-			}
-		} else if (revs.max_count < 0 &&
-			   revs.tag_objects && revs.tree_objects && revs.blob_objects) {
-			struct bitmap_index *bitmap_git;
-			if ((bitmap_git = prepare_bitmap_walk(&revs))) {
-				traverse_bitmap_commit_list(bitmap_git, &show_object_fast);
-				free_bitmap_index(bitmap_git);
-				return 0;
-			}
-		}
+	if (use_bitmap_index) {
+		if (!try_bitmap_count(&revs, &filter_options))
+			return 0;
+		if (!try_bitmap_traversal(&revs, &filter_options))
+			return 0;
 	}
 
 	if (prepare_revision_walk(&revs))
@@ -569,8 +637,15 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix)
 
 	if (bisect_list) {
 		int reaches, all;
+		unsigned bisect_flags = 0;
+
+		if (bisect_find_all)
+			bisect_flags |= FIND_BISECTION_ALL;
+
+		if (revs.first_parent_only)
+			bisect_flags |= FIND_BISECTION_FIRST_PARENT_ONLY;
 
-		find_bisection(&revs.commits, &reaches, &all, bisect_find_all);
+		find_bisection(&revs.commits, &reaches, &all, bisect_flags);
 
 		if (bisect_show_vars)
 			return show_bisect_vars(&info, reaches, all);