Re: [PATCH 2/2] Support "history replay" for git log commands

This notices if we aren't in topological order, and replays the history. 
Thus avoiding the need to sort history up front.
    
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

See the code and the more complete explanations in [PATCH 0/2]. In 
particular, see the last section there about the downsides of this: the 
50x expansion of output on the kernel is unacceptable, but if somebody can 
make a graphical viewer that can react correctly to the "Replay" thing, 
I'm sure I can make the replays themselves happen much more rarely.

 builtin-blame.c |    2 +-
 builtin-log.c   |   35 +++++++++++++++++++++++++++++++++++
 log-tree.c      |   10 +++++++---
 revision.c      |   29 ++++++++++++++++++++++-------
 revision.h      |    6 +++++-
 5 files changed, 70 insertions(+), 12 deletions(-)

diff --git a/builtin-blame.c b/builtin-blame.c
index 8432b82..7b6af8c 100644
--- a/builtin-blame.c
+++ b/builtin-blame.c

@@ -1502,7 +1502,7 @@ static void assign_blame(struct scoreboard *sb, struct rev_info *revs, int opt)
 		else {
 			commit->object.flags |= UNINTERESTING;
 			if (commit->object.parsed)
-				mark_parents_uninteresting(commit);
+				mark_parents_uninteresting(revs, commit);
 		}
 		/* treat root commit as boundary */
 		if (!commit->parents && !show_root)

diff --git a/builtin-log.c b/builtin-log.c
index e8b982d..10e0821 100644
--- a/builtin-log.c
+++ b/builtin-log.c

@@ -77,6 +77,35 @@ static void cmd_log_init(int argc, const char **argv, const char *prefix,
 	}
 }
 
+static void replay_history(struct rev_info *revs)
+{
+	struct commit_list *entry;
+
+	revs->trigger_replay = 0;
+	while ((entry = revs->shown) != NULL) {
+		struct commit *commit = entry->item;
+		unsigned flags = commit->object.flags;
+
+		/* Undo the SHOWN and FORCE_REPLAY bits */
+		commit->object.flags = flags & ~(SHOWN | FORCE_REPLAY);
+		commit->indegree = 0;
+
+		/* Remove it from the shown list, put it on the commit list */
+		revs->shown = entry->next;
+		entry->next = revs->commits;
+		revs->commits = entry;
+
+		printf("Replay %s\n", sha1_to_hex(commit->object.sha1));
+
+		/* Was this the one that caused us to replay? */
+		if (flags & FORCE_REPLAY)
+			break;