[PATCH v1 1/4] make rewrite_parents an external function

[Bo Yang <struggleyb.nku@gmail.com>]

The function rewrite_one is used to rewrite a single
parent of the current commit, and is used by rewrite_parents
to rewrite all the parents.
This commit decouple the dependence between them, make
rewrite_one as a callback function and be passed to
rewrite_parents. Make rewrite_parents public to other
part of git.
We will use this function in line.c.

Signed-off-by: Bo Yang <struggleyb.nku@gmail.com>
---
 revision.c |   11 +++--------
 revision.h |   10 ++++++++++
 2 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/revision.c b/revision.c
index 63f37ea..72d9654 100644
--- a/revision.c
+++ b/revision.c
@@ -1893,12 +1893,6 @@ int prepare_revision_walk(struct rev_info *revs)
 	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)
 {
 	struct commit_list *cache = NULL;
@@ -1920,7 +1914,8 @@ static enum rewrite_result rewrite_one(struct rev_info *revs, struct commit **pp
 	}
 }
 
-static int rewrite_parents(struct rev_info *revs, struct commit *commit)
+int rewrite_parents(struct rev_info *revs, struct commit *commit,
+	rewrite_parent rewrite_one)
 {
 	struct commit_list **pp = &commit->parents;
 	while (*pp) {
@@ -1993,7 +1988,7 @@ enum commit_action simplify_commit(struct rev_info *revs, struct commit *commit)
 	if (action == commit_show &&
 	    !revs->show_all &&
 	    revs->prune && revs->dense && want_ancestry(revs)) {
-		if (rewrite_parents(revs, commit) < 0)
+		if (rewrite_parents(revs, commit, rewrite_one) < 0)
 			return commit_error;
 	}
 	return action;
diff --git a/revision.h b/revision.h
index 433da9a..9b8e3d9 100644
--- a/revision.h
+++ b/revision.h
@@ -200,4 +200,14 @@ enum commit_action {
 extern enum commit_action get_commit_action(struct rev_info *revs, struct commit *commit);
 extern enum commit_action simplify_commit(struct rev_info *revs, struct commit *commit);
 
+enum rewrite_result {
+	rewrite_one_ok,
+	rewrite_one_noparents,
+	rewrite_one_error
+};
+
+typedef enum rewrite_result (*rewrite_parent)(struct rev_info *revs, struct commit **pp);
+
+extern int rewrite_parents(struct rev_info *revs, struct commit *commit,
+	rewrite_parent rewrite_one);
 #endif
-- 
1.7.0.2.273.gc2413.dirty