rerere: handle leftover rr-cache/$ID directory and postimage files
If by some accident there is only $GIT_DIR/rr-cache/$ID directory existed, we wouldn't have recorded a preimage for a conflict that is newly encountered, which would mean after a manual resolution, we wouldn't have recorded it by storing the postimage, because the logic used to be "if there is no rr-cache/$ID directory, then we are the first so record the preimage". Instead, record preimage if we do not have one. In addition, if there is only $GIT_DIR/rr-cache/$ID/postimage without corresponding preimage, we would have tried to call into merge() and punted. These would have been a situation frustratingly hard to recover from. Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano committed
Jul 17, 2015 at 13:28 UTC
05dd9f139d6a7e4c7cd22d8d3b57faf5be88a571
2 files changed
+41
-18
rerere.c
+25
-17
@@ -117,7 +117,9 @@ static struct rerere_dir *find_rerere_dir(const char *hex)
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static int has_rerere_resolution(const struct rerere_id *id)
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{
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- return (id->collection->status & RR_HAS_POSTIMAGE);
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+ const int both = RR_HAS_POSTIMAGE|RR_HAS_PREIMAGE;
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+
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+ return ((id->collection->status & both) == both);
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}
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static struct rerere_id *new_rerere_id_hex(char *hex)
@@ -806,24 +808,30 @@ static int do_plain_rerere(struct string_list *rr, int fd)
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string_list_insert(rr, path)->util = id;
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/*
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- * If the directory does not exist, create
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- * it. mkdir_in_gitdir() will fail with
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- * EEXIST if there already is one.
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- *
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- * NEEDSWORK: make sure "gc" does not remove
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- * preimage without removing the directory.
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+ * Ensure that the directory exists.
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+ * mkdir_in_gitdir() will fail with EEXIST if there
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+ * already is one.
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*/
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- if (mkdir_in_gitdir(rerere_path(id, NULL)))
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- continue;
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+ if (mkdir_in_gitdir(rerere_path(id, NULL)) &&
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+ errno != EEXIST)
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+ continue; /* NEEDSWORK: perhaps we should die? */
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- /*
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- * We are the first to encounter this
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- * conflict. Ask handle_file() to write the
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- * normalized contents to the "preimage" file.
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- */
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- handle_file(path, NULL, rerere_path(id, "preimage"));
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- id->collection->status |= RR_HAS_PREIMAGE;
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- fprintf(stderr, "Recorded preimage for '%s'\n", path);
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+ if (id->collection->status & RR_HAS_PREIMAGE) {
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+ ;
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+ } else {
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+ /*
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+ * We are the first to encounter this
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+ * conflict. Ask handle_file() to write the
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+ * normalized contents to the "preimage" file.
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+ *
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+ * NEEDSWORK: what should happen if we had a
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+ * leftover postimage that is totally
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+ * unrelated? Perhaps we should unlink it?
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+ */
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+ handle_file(path, NULL, rerere_path(id, "preimage"));
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+ id->collection->status |= RR_HAS_PREIMAGE;
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+ fprintf(stderr, "Recorded preimage for '%s'\n", path);
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+ }
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}
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for (i = 0; i < rr->nr; i++)
t/t4200-rerere.sh
+16
-1
@@ -184,12 +184,27 @@ test_expect_success 'rerere updates postimage timestamp' '
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'
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test_expect_success 'rerere clear' '
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- rm $rr/postimage &&
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+ mv $rr/postimage .git/post-saved &&
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echo "$sha1 a1" | perl -pe "y/\012/\000/" >.git/MERGE_RR &&
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git rerere clear &&
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! test -d $rr
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'
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+test_expect_success 'leftover directory' '
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+ git reset --hard &&
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+ mkdir -p $rr &&
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+ test_must_fail git merge first &&
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+ test -f $rr/preimage
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+'
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+
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+test_expect_success 'missing preimage' '
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+ git reset --hard &&
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+ mkdir -p $rr &&
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+ cp .git/post-saved $rr/postimage &&
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+ test_must_fail git merge first &&
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+ test -f $rr/preimage
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+'
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+
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test_expect_success 'set up for garbage collection tests' '
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mkdir -p $rr &&
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echo Hello >$rr/preimage &&