int parse_commit(struct commit *item);
void parse_commit_or_die(struct commit *item);
+/*
+ * Associate an object buffer with the commit. The ownership of the
+ * memory is handed over to the commit, and must be free()-able.
+ */
+void set_commit_buffer(struct commit *, void *buffer);
+
+/*
+ * Get any cached object buffer associated with the commit. Returns NULL
+ * if none. The resulting memory should not be freed.
+ */
+const void *get_cached_commit_buffer(const struct commit *);
+
+/*
+ * Get the commit's object contents, either from cache or by reading the object
+ * from disk. The resulting memory should not be modified, and must be given
+ * to unuse_commit_buffer when the caller is done.
+ */
+const void *get_commit_buffer(const struct commit *);
+
+/*
+ * Tell the commit subsytem that we are done with a particular commit buffer.
+ * The commit and buffer should be the input and return value, respectively,
+ * from an earlier call to get_commit_buffer. The buffer may or may not be
+ * freed by this call; callers should not access the memory afterwards.
+ */
+void unuse_commit_buffer(const struct commit *, const void *buffer);
+
+/*
+ * Free any cached object buffer associated with the commit.
+ */
+void free_commit_buffer(struct commit *);
+
+/*
+ * Disassociate any cached object buffer from the commit, but do not free it.
+ * The buffer (or NULL, if none) is returned.
+ */
+const void *detach_commit_buffer(struct commit *);
+
/* Find beginning and length of commit subject. */
int find_commit_subject(const char *commit_buffer, const char **subject);