Re: Bug in "git rev-parse --verify"
- From
Junio C Hamano <gitster@pobox.com>
- Date
- Mar 30, 2013, 07:05 UTC
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- <7vhajtpdtc.fsf@alter.siamese.dyndns.org>
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- <7vboa1qtnb.fsf@alter.siamese.dyndns.org>
Junio C Hamano <gitster@pobox.com> writes:
Show 14 quoted lines
> What we may want is another type peeling operator, ^{object}.
> that makes sure it is an object, like this:
>
> rev-parse --verify 572a535454612a046e7dd7404dcca94d6243c788^{object}
>
> It asks "I have this 40-hex; I want an object out of it", just like
> frotz^{tree} is "I have 'frotz'; I want a tree-ish" for any value of
> 'frotz'.
>
> With that, a use case that it wants to see _any_ object can safely
> use 'rev-parse --verify "$userinput^{object}' without an annotated
> tag getting in the way.
>
> How does that sound?Perhaps something like this. Note that the last hunk is unrelated thinko-fix I noticed while browsing the code.
-- >8 --
Subject: sha1_name.c: ^{object} peelerA string that names an object can be suffixed with ^{type} peeler to say "I have this object name; peel it until you get this type. If you cannot do so, it is an error". v1.8.2^{commit} asks for a commit that is pointed at an annotated tag v1.8.2; v1.8.2^{tree} unwraps it further to the top-level tree object. A special suffix ^{} (i.e. no type specified) means "I do not care what it unwraps to; just peel annotated tag until you get something that is not a tag".
When you have a random user-supplied string, you can turn it to a bare 40-hex object name, and cause it to error out if such an object does not exist, with:
git rev-parse --verify "$userstring^{}"for most objects, but this does not yield the tag object name when $userstring refers to an annotated tag.
Introduce a new suffix, ^{object}, that only makes sure the given name refers to an existing object. Then
git rev-parse --verify "$userstring^{object}"becomes a way to make sure $userstring refers to an existing object.
Signed-off-by: Junio C Hamano <gitster@pobox.com> --- sha1_name.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/sha1_name.c b/sha1_name.c index c50630a..85b6e75 100644 --- a/sha1_name.c +++ b/sha1_name.c @@ -594,7 +594,7 @@ struct object *peel_to_type(const char *name, int namelen, while (1) { if (!o || (!o->parsed && !parse_object(o->sha1))) return NULL; - if (o->type == expected_type) + if (expected_type == OBJ_ANY || o->type == expected_type) return o; if (o->type == OBJ_TAG) o = ((struct tag*) o)->tagged; @@ -645,6 +645,8 @@ static int peel_onion(const char *name, int len, unsigned char *sha1) expected_type = OBJ_TREE; else if (!strncmp(blob_type, sp, 4) && sp[4] == '}') expected_type = OBJ_BLOB; + else if (!prefixcmp(sp, "object}")) + expected_type = OBJ_ANY; else if (sp[0] == '}') expected_type = OBJ_NONE; else if (sp[0] == '/') @@ -654,6 +656,8 @@ static int peel_onion(const char *name, int len, unsigned char *sha1) if (expected_type == OBJ_COMMIT) lookup_flags = GET_SHA1_COMMITTISH; + else if (expected_type == OBJ_TREE) + lookup_flags = GET_SHA1_TREEISH; if (get_sha1_1(name, sp - name - 2, outer, lookup_flags)) return -1;