[PATCH] Add some functions for commit lists

This adds a function for inserting an item in a commit list, a function
for sorting a commit list by date, and a function for progressively
scanning a commit history from most recent to least recent.

Signed-Off-By: Daniel Barkalow <barkalow@iabervon.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/commit.c b/commit.c
index 9f0668e..911f643 100644 (file)
--- a/commit.c
+++ b/commit.c
@@ -63,12 +63,9 @@ int parse_commit(struct commit *item)
        bufptr += 46; /* "tree " + "hex sha1" + "\n" */
        while (!memcmp(bufptr, "parent ", 7) &&
               !get_sha1_hex(bufptr + 7, parent)) {
-               struct commit_list *new_parent = 
-                       malloc(sizeof(struct commit_list));
-               new_parent->next = item->parents;
-               new_parent->item = lookup_commit(parent);
-               add_ref(&item->object, &new_parent->item->object);
-               item->parents = new_parent;
+               struct commit *new_parent = lookup_commit(parent);
+               commit_list_insert(new_parent, &item->parents);
+               add_ref(&item->object, &new_parent->object);
                bufptr += 48;
        }
        item->date = parse_commit_date(bufptr);
@@ -76,6 +73,14 @@ int parse_commit(struct commit *item)
        return 0;
 }
 
+void commit_list_insert(struct commit *item, struct commit_list **list_p)
+{
+       struct commit_list *new_list = malloc(sizeof(struct commit_list));
+       new_list->item = item;
+       new_list->next = *list_p;
+       *list_p = new_list;
+}
+
 void free_commit_list(struct commit_list *list)
 {
        while (list) {
@@ -84,3 +89,44 @@ void free_commit_list(struct commit_list *list)
                free(temp);
        }
 }
+
+static void insert_by_date(struct commit_list **list, struct commit *item)
+{
+       struct commit_list **pp = list;
+       struct commit_list *p;
+       while ((p = *pp) != NULL) {
+               if (p->item->date < item->date) {
+                       break;
+               }
+               pp = &p->next;
+       }
+       commit_list_insert(item, pp);
+}
+
+       
+void sort_by_date(struct commit_list **list)
+{
+       struct commit_list *ret = NULL;
+       while (*list) {
+               insert_by_date(&ret, (*list)->item);
+               *list = (*list)->next;
+       }
+       *list = ret;
+}
+
+struct commit *pop_most_recent_commit(struct commit_list **list)
+{
+       struct commit *ret = (*list)->item;
+       struct commit_list *parents = ret->parents;
+       struct commit_list *old = *list;
+
+       *list = (*list)->next;
+       free(old);
+
+       while (parents) {
+               parse_commit(parents->item);
+               insert_by_date(list, parents->item);
+               parents = parents->next;
+       }
+       return ret;
+}

diff --git a/commit.h b/commit.h
index 4afd27b..c8684d1 100644 (file)
--- a/commit.h
+++ b/commit.h
@@ -22,6 +22,15 @@ struct commit *lookup_commit(unsigned char *sha1);
 
 int parse_commit(struct commit *item);
 
+void commit_list_insert(struct commit *item, struct commit_list **list_p);
+
 void free_commit_list(struct commit_list *list);
 
+void sort_by_date(struct commit_list **list);
+
+/** Removes the first commit from a list sorted by date, and adds all
+ * of its parents.
+ **/
+struct commit *pop_most_recent_commit(struct commit_list **list);
+
 #endif /* COMMIT_H */