From 1f1e895fccc52a1e227c464c4558d74604301a9f Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Mon, 19 Jun 2006 17:42:35 -0700 Subject: Add "named object array" concept We've had this notion of a "object_list" for a long time, which eventually grew a "name" member because some users (notably git-rev-list) wanted to name each object as it is generated. That object_list is great for some things, but it isn't all that wonderful for others, and the "name" member is generally not used by everybody. This patch splits the users of the object_list array up into two: the traditional list users, who want the list-like format, and who don't actually use or want the name. And another class of users that really used the list as an extensible array, and generally wanted to name the objects. The patch is fairly straightforward, but it's also biggish. Most of it really just cleans things up: switching the revision parsing and listing over to the array makes things like the builtin-diff usage much simpler (we now see exactly how many members the array has, and we don't get the objects reversed from the order they were on the command line). One of the main reasons for doing this at all is that the malloc overhead of the simple object list was actually pretty high, and the array is just a lot denser. So this patch brings down memory usage by git-rev-list by just under 3% (on top of all the other memory use optimizations) on the mozilla archive. It does add more lines than it removes, and more importantly, it adds a whole new infrastructure for maintaining lists of objects, but on the other hand, the new dynamic array code is pretty obvious. The change to builtin-diff-tree.c shows a fairly good example of why an array interface is sometimes more natural, and just much simpler for everybody. Signed-off-by: Linus Torvalds Signed-off-by: Junio C Hamano --- builtin-diff-tree.c | 42 ++++++++++++------------------------------ 1 file changed, 12 insertions(+), 30 deletions(-) (limited to 'builtin-diff-tree.c') diff --git a/builtin-diff-tree.c b/builtin-diff-tree.c index 58cf65856d..3409a39a9f 100644 --- a/builtin-diff-tree.c +++ b/builtin-diff-tree.c @@ -65,7 +65,6 @@ int cmd_diff_tree(int argc, const char **argv, char **envp) char line[1000]; struct object *tree1, *tree2; static struct rev_info *opt = &log_tree_opt; - struct object_list *list; int read_stdin = 0; git_config(git_diff_config); @@ -86,45 +85,28 @@ int cmd_diff_tree(int argc, const char **argv, char **envp) } /* - * NOTE! "setup_revisions()" will have inserted the revisions - * it parsed in reverse order. So if you do - * - * git-diff-tree a b - * - * the commit list will be "b" -> "a" -> NULL, so we reverse - * the order of the objects if the first one is not marked - * UNINTERESTING. + * NOTE! We expect "a ^b" to be equal to "a..b", so we + * reverse the order of the objects if the second one + * is marked UNINTERESTING. */ - nr_sha1 = 0; - list = opt->pending_objects; - if (list) { - nr_sha1++; - tree1 = list->item; - list = list->next; - if (list) { - nr_sha1++; - tree2 = tree1; - tree1 = list->item; - if (list->next) - usage(diff_tree_usage); - /* Switch them around if the second one was uninteresting.. */ - if (tree2->flags & UNINTERESTING) { - struct object *tmp = tree2; - tree2 = tree1; - tree1 = tmp; - } - } - } - + nr_sha1 = opt->pending.nr; switch (nr_sha1) { case 0: if (!read_stdin) usage(diff_tree_usage); break; case 1: + tree1 = opt->pending.objects[0].item; diff_tree_commit_sha1(tree1->sha1); break; case 2: + tree1 = opt->pending.objects[0].item; + tree2 = opt->pending.objects[1].item; + if (tree2->flags & UNINTERESTING) { + struct object *tmp = tree2; + tree2 = tree1; + tree1 = tmp; + } diff_tree_sha1(tree1->sha1, tree2->sha1, "", &opt->diffopt); -- cgit v1.2.3