diff options
author | Junio C Hamano <gitster@pobox.com> | 2015-07-01 08:36:35 +0300 |
---|---|---|
committer | Junio C Hamano <gitster@pobox.com> | 2015-07-25 02:02:06 +0300 |
commit | 4b68c2a0877b18d1fe591dd7aee55aa1158fada0 (patch) | |
tree | 6841fbba4f08ad2325ed9d5b6dee87be78ef7a50 | |
parent | d3c2749def9563798cea3486f3793ad36d9c1030 (diff) |
rerere: explain MERGE_RR management helpers
Explain the internals of rerere as in-code comments, while
sprinkling "NEEDSWORK" comment to highlight iffy bits and
questionable assumptions.
This one covers the "$GIT_DIR/MERGE_RR" file and in-core merge_rr
that are used to keep track of the status of "rerere" session in
progress.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
-rw-r--r-- | rerere.c | 41 |
1 files changed, 41 insertions, 0 deletions
@@ -33,6 +33,13 @@ static int has_rerere_resolution(const char *hex) return !stat(rerere_path(hex, "postimage"), &st); } +/* + * $GIT_DIR/MERGE_RR file is a collection of records, each of which is + * "conflict ID", a HT and pathname, terminated with a NUL, and is + * used to keep track of the set of paths that "rerere" may need to + * work on (i.e. what is left by the previous invocation of "git + * rerere" during the current conflict resolution session). + */ static void read_rr(struct string_list *rr) { struct strbuf buf = STRBUF_INIT; @@ -403,6 +410,14 @@ static int handle_cache(const char *path, unsigned char *sha1, const char *outpu return hunk_no; } +/* + * Look at a cache entry at "i" and see if it is not conflicting, + * conflicting and we are willing to handle, or conflicting and + * we are unable to handle, and return the determination in *type. + * Return the cache index to be looked at next, by skipping the + * stages we have already looked at in this invocation of this + * function. + */ static int check_one_conflict(int i, int *type) { const struct cache_entry *e = active_cache[i]; @@ -434,6 +449,17 @@ static int check_one_conflict(int i, int *type) return i; } +/* + * Scan the index and find paths that have conflicts that rerere can + * handle, i.e. the ones that has both stages #2 and #3. + * + * NEEDSWORK: we do not record or replay a previous "resolve by + * deletion" for a delete-modify conflict, as that is inherently risky + * without knowing what modification is being discarded. The only + * safe case, i.e. both side doing the deletion and modification that + * are identical to the previous round, might want to be handled, + * though. + */ static int find_conflict(struct string_list *conflict) { int i; @@ -450,6 +476,21 @@ static int find_conflict(struct string_list *conflict) return 0; } +/* + * The merge_rr list is meant to hold outstanding conflicted paths + * that rerere could handle. Abuse the list by adding other types of + * entries to allow the caller to show "rerere remaining". + * + * - Conflicted paths that rerere does not handle are added + * - Conflicted paths that have been resolved are marked as such + * by storing RERERE_RESOLVED to .util field (where conflict ID + * is expected to be stored). + * + * Do *not* write MERGE_RR file out after calling this function. + * + * NEEDSWORK: we may want to fix the caller that implements "rerere + * remaining" to do this without abusing merge_rr. + */ int rerere_remaining(struct string_list *merge_rr) { int i; |