Re: How to replace a single corrupt, packed object?
- From
Nicolas Pitre <nico@cam.org>
- Date
- Aug 11, 2008, 02:55 UTC
- Message-ID
- <alpine.LFD.1.10.0808102146050.22892@xanadu.home>
- In-Reply-To
- <alpine.DEB.1.00.0808081841290.24820@pacific.mpi-cbg.de.mpi-cbg.de>
On Fri, 8 Aug 2008, Johannes Schindelin wrote:
> In any case, the pack is too large for me to let my computer repack > everything, when only one object needs repacking.
By that you mean you cannot/don't want to use repack -f, right?
There _could_ be a way to hack pack-objects so not to reuse bad objects. However I don't want that to impact the code too much for an event that hopefully should almost never happens, especially if using -f does work around it already.
Well, let's see.
[...]
OK, here's what the patch to allow repacking without -f and still using redundant objects in presence of pack corruption might look like. Please tell me if that works for you.
diff --git a/builtin-pack-objects.c b/builtin-pack-objects.c index 2dadec1..88e73f3 100644 --- a/builtin-pack-objects.c +++ b/builtin-pack-objects.c @@ -277,6 +277,7 @@ static unsigned long write_object(struct sha1file *f, */ if (!to_reuse) { + no_reuse: if (!usable_delta) { buf = read_sha1_file(entry->idx.sha1, &type, &size); if (!buf) @@ -364,14 +365,28 @@ static unsigned long write_object(struct sha1file *f, reused_delta++; } hdrlen = encode_header(type, entry->size, header); + offset = entry->in_pack_offset; revidx = find_pack_revindex(p, offset); datalen = revidx[1].offset - offset; if (!pack_to_stdout && p->index_version > 1 && - check_pack_crc(p, &w_curs, offset, datalen, revidx->nr)) - die("bad packed object CRC for %s", sha1_to_hex(entry->idx.sha1)); + check_pack_crc(p, &w_curs, offset, datalen, revidx->nr)) { + error("bad packed object CRC for %s", sha1_to_hex(entry->idx.sha1)); + if (entry->delta) + reused_delta--; + goto no_reuse; + } + offset += entry->in_pack_header_size; datalen -= entry->in_pack_header_size; + if (!pack_to_stdout && p->index_version == 1 && + check_pack_inflate(p, &w_curs, offset, datalen, entry->size)) { + die("corrupt packed object for %s", sha1_to_hex(entry->idx.sha1)); + if (entry->delta) + reused_delta--; + goto no_reuse; + } + if (type == OBJ_OFS_DELTA) { off_t ofs = entry->idx.offset - entry->delta->idx.offset; unsigned pos = sizeof(dheader) - 1; @@ -394,10 +409,6 @@ static unsigned long write_object(struct sha1file *f, return 0; sha1write(f, header, hdrlen); } - - if (!pack_to_stdout && p->index_version == 1 && - check_pack_inflate(p, &w_curs, offset, datalen, entry->size)) - die("corrupt packed object for %s", sha1_to_hex(entry->idx.sha1)); copy_pack_data(f, p, &w_curs, offset, datalen); unuse_pack(&w_curs); reused++; Nicolas