commit/revisions: bookkeeping before refactoring

There are a few things that need to move around a little before
making a big refactoring in the topo-order logic:

1. We need access to record_author_date() and
   compare_commits_by_author_date() in revision.c. These are used
   currently by sort_in_topological_order() in commit.c.

2. Moving these methods to commit.h requires adding the author_slab
   definition to commit.h.

3. The add_parents_to_list() method in revision.c performs logic
   around the UNINTERESTING flag and other special cases depending
   on the struct rev_info. Allow this method to ignore a NULL 'list'
   parameter, as we will not be populating the list for our walk.

Signed-off-by: Derrick Stolee <[email protected]>

Author: derrickstolee

commit.c

@@ -655,11 +655,8 @@ struct commit *pop_commit(struct commit_list **stack)
 /* count number of children that have not been emitted */
 define_commit_slab(indegree_slab, int);
 
-/* record author-date for each commit object */
-define_commit_slab(author_date_slab, unsigned long);
-
-static void record_author_date(struct author_date_slab *author_date,
-			       struct commit *commit)
+void record_author_date(struct author_date_slab *author_date,
+			struct commit *commit)
 {
 	const char *buffer = get_commit_buffer(commit, NULL);
 	struct ident_split ident;
@@ -684,8 +681,8 @@ static void record_author_date(struct author_date_slab *author_date,
 	unuse_commit_buffer(commit, buffer);
 }
 
-static int compare_commits_by_author_date(const void *a_, const void *b_,
-					  void *cb_data)
+int compare_commits_by_author_date(const void *a_, const void *b_,
+				   void *cb_data)
 {
 	const struct commit *a = a_, *b = b_;
 	struct author_date_slab *author_date = cb_data;

commit.h

@@ -8,6 +8,7 @@
 #include "gpg-interface.h"
 #include "string-list.h"
 #include "pretty.h"
+#include "commit-slab.h"
 
 #define COMMIT_NOT_FROM_GRAPH 0xFFFFFFFF
 #define GENERATION_NUMBER_INFINITY 0xFFFFFFFF
@@ -328,6 +329,13 @@ extern int remove_signature(struct strbuf *buf);
  */
 extern int check_commit_signature(const struct commit *commit, struct signature_check *sigc);
 
+/* record author-date for each commit object */
+define_commit_slab(author_date_slab, timestamp_t);
+
+void record_author_date(struct author_date_slab *author_date,
+			struct commit *commit);
+
+int compare_commits_by_author_date(const void *a_, const void *b_, void *unused);
 int compare_commits_by_commit_date(const void *a_, const void *b_, void *unused);
 int compare_commits_by_gen_then_commit_date(const void *a_, const void *b_, void *unused);
 

revision.c

@@ -804,7 +804,8 @@ static int add_parents_to_list(struct rev_info *revs, struct commit *commit,
 			if (p->object.flags & SEEN)
 				continue;
 			p->object.flags |= SEEN;
-			commit_list_insert_by_date_cached(p, list, cached_base, cache_ptr);
+			if (list)
+				commit_list_insert_by_date_cached(p, list, cached_base, cache_ptr);
 		}
 		return 0;
 	}
@@ -843,7 +844,8 @@ static int add_parents_to_list(struct rev_info *revs, struct commit *commit,
 		p->object.flags |= left_flag;
 		if (!(p->object.flags & SEEN)) {
 			p->object.flags |= SEEN;
-			commit_list_insert_by_date_cached(p, list, cached_base, cache_ptr);
+			if (list)
+				commit_list_insert_by_date_cached(p, list, cached_base, cache_ptr);
 		}
 		if (revs->first_parent_only)
 			break;