Jeff King <p...@peff.net> writes: > This part I don't understand, though. We clearly need to look for the > NUL. But why do we need to look for the space? The loop in > parse_sha1_header() can easily detect this as it looks for the end of > the type name (and if it hits the end-of-string, can bail as in your > original patch). > I.e., the root of the problem is that we pass parse_sha1_header() a the > "ptr" half of a ptr/len buffer, and it has no idea how much we read. > But once we get it that information (either by passing the length, or by > ensuring that the buffer is NUL-terminated, it should be easy for it to > do the right thing.
Yup. > Anyway, here's my ptr/len version (which passes the length back out of > unpack_sha1_header via an in/out pointer). After thinking on it, though, > I'm of the opinion that we're better off just ensuring that "hdr" is > NUL-terminated. We end up assuming that anyway later, since we have to > know how much of the header buffer was consumed by parsing. I'd agree, not because I didn't first go in this <ptr,len> route myself, but because the attached change does look quite invasive. Also, I think it is OK to ask unpack_*_header() to fail if what it turns can no way be a header, e.g. lacks NUL termination. > Do note the final call below in the streaming loose-open code, which > exhibits that, but also seems to call parse_sha1_header() without > checking its return value. I think that needs fixed regardless of the > approach. Good that your attempt to signature-changing change caught it. I'll take a further look. Thanks.