apply: fall back on three-way merge
Grab the preimage blob the patch claims to be based on out of the object store, apply the patch, and then call three-way-merge function. This step still does not plug the actual three-way merge logic yet, but we are getting there. Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano committed
Jun 8, 2012 at 09:54 UTC
519d1a5b4e044459bd7323cfa6a7cb98cec5c884
1 file changed
+45
-1
builtin/apply.c
+45
-1
@@ -3140,10 +3140,54 @@ static int load_preimage(struct image *image,
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return 0;
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}
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+static int three_way_merge(struct image *image,
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+ char *path,
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+ const unsigned char *base,
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+ const unsigned char *ours,
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+ const unsigned char *theirs)
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+{
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+ return -1; /* for now */
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+}
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+
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static int try_threeway(struct image *image, struct patch *patch,
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struct stat *st, struct cache_entry *ce)
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{
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- return -1; /* for now */
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+ unsigned char pre_sha1[20], post_sha1[20], our_sha1[20];
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+ struct strbuf buf = STRBUF_INIT;
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+ size_t len;
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+ char *img;
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+ struct image tmp_image;
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+
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+ /* No point falling back to 3-way merge in these cases */
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+ if (patch->is_new || patch->is_delete ||
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+ S_ISGITLINK(patch->old_mode) || S_ISGITLINK(patch->new_mode))
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+ return -1;
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+
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+ /* Preimage the patch was prepared for */
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+ if (get_sha1(patch->old_sha1_prefix, pre_sha1) ||
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+ read_blob_object(&buf, pre_sha1, patch->old_mode))
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+ return error("repository lacks the necessary blob to fall back on 3-way merge.");
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+ img = strbuf_detach(&buf, &len);
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+ prepare_image(&tmp_image, img, len, 1);
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+ /* Apply the patch to get the post image */
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+ if (apply_fragments(&tmp_image, patch) < 0) {
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+ clear_image(&tmp_image);
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+ return -1;
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+ }
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+ /* post_sha1[] is theirs */
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+ write_sha1_file(tmp_image.buf, tmp_image.len, blob_type, post_sha1);
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+ clear_image(&tmp_image);
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+
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+ /* our_sha1[] is ours */
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+ if (load_preimage(&tmp_image, patch, st, ce))
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+ return error("cannot read the current contents of '%s'",
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+ patch->old_name);
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+ write_sha1_file(tmp_image.buf, tmp_image.len, blob_type, our_sha1);
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+ clear_image(&tmp_image);
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+
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+ /* in-core three-way merge between post and our using pre as base */
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+ return three_way_merge(image,
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+ patch->new_name, pre_sha1, our_sha1, post_sha1);
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}
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static int apply_data(struct patch *patch, struct stat *st, struct cache_entry *ce)