From: Junio C Hamano <gitster@pobox•com>
To: Jonathan Tan <jonathantanmy@google•com>
Cc: git@vger•kernel.org
Subject: Re: [PATCH 2/2] sha1_file: remove read_packed_sha1()
Date: Fri, 11 Aug 2017 15:06:54 -0700 [thread overview]
Message-ID: <xmqqa835zrlt.fsf@gitster.mtv.corp.google.com> (raw)
In-Reply-To: <557fbeeac6a0f65d48ba0902f20c0650e75ae332.1502483486.git.jonathantanmy@google.com> (Jonathan Tan's message of "Fri, 11 Aug 2017 13:36:15 -0700")
Jonathan Tan <jonathantanmy@google•com> writes:
> Use read_object() in its place instead. This avoids duplication of code.
>
> This makes force_object_loose() slightly slower (because of a redundant
> check of loose object storage), but only in the error case.
>
> Signed-off-by: Jonathan Tan <jonathantanmy@google•com>
> ---
> sha1_file.c | 26 +-------------------------
> 1 file changed, 1 insertion(+), 25 deletions(-)
The original code insisted on reading from pack and never from a
loose object, because it knew it would return early when it found a
loose version. Now we allow a loose one to appear in the middle of
force_object_loose() operation and happily read from it when we do
not see a pack entry for the object---presumably because we are
racing with another simultanous repack process, or something?---and
then write it out as a new (and identical) loose object, which would
not do any harm.
So this is not strictly a no-op conversion; I have a gut feeling
that it would make it more robust, not less, in the presence of
another racing repack process, but I haven't really thought through
race scenarios that may make difference in its behaviour.
> diff --git a/sha1_file.c b/sha1_file.c
> index 910109fd9..0f758eabf 100644
> --- a/sha1_file.c
> +++ b/sha1_file.c
> @@ -3062,30 +3062,6 @@ int sha1_object_info(const unsigned char *sha1, unsigned long *sizep)
> return type;
> }
>
> -static void *read_packed_sha1(const unsigned char *sha1,
> - enum object_type *type, unsigned long *size)
> -{
> - struct pack_entry e;
> - void *data;
> -
> - if (!find_pack_entry(sha1, &e))
> - return NULL;
> - data = cache_or_unpack_entry(e.p, e.offset, size, type);
> - if (!data) {
> - /*
> - * We're probably in deep shit, but let's try to fetch
> - * the required object anyway from another pack or loose.
> - * This should happen only in the presence of a corrupted
> - * pack, and is better than failing outright.
> - */
> - error("failed to read object %s at offset %"PRIuMAX" from %s",
> - sha1_to_hex(sha1), (uintmax_t)e.offset, e.p->pack_name);
> - mark_bad_packed_object(e.p, sha1);
> - data = read_object(sha1, type, size);
> - }
> - return data;
> -}
> -
> int pretend_sha1_file(void *buf, unsigned long len, enum object_type type,
> unsigned char *sha1)
> {
> @@ -3468,7 +3444,7 @@ int force_object_loose(const unsigned char *sha1, time_t mtime)
>
> if (has_loose_object(sha1))
> return 0;
> - buf = read_packed_sha1(sha1, &type, &len);
> + buf = read_object(sha1, &type, &len);
> if (!buf)
> return error("cannot read sha1_file for %s", sha1_to_hex(sha1));
> hdrlen = xsnprintf(hdr, sizeof(hdr), "%s %lu", typename(type), len) + 1;
next prev parent reply other threads:[~2017-08-11 22:07 UTC|newest]
Thread overview: 88+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-08-08 19:32 [RFC PATCH 00/10] An attempt to move packfile funcs to its own file Jonathan Tan
2017-08-08 19:32 ` [RFC PATCH 01/10] pack: move pack name-related functions Jonathan Tan
2017-08-08 20:36 ` Stefan Beller
2017-08-08 20:50 ` Jonathan Tan
2017-08-09 12:00 ` Christian Couder
2017-08-09 17:16 ` Jonathan Tan
2017-08-11 19:38 ` Ben Peart
2017-08-11 21:34 ` Junio C Hamano
2017-08-16 22:53 ` Jonathan Tan
2017-08-08 19:32 ` [RFC PATCH 02/10] pack: move static state variables Jonathan Tan
2017-08-08 19:32 ` [RFC PATCH 03/10] pack: move pack_report() Jonathan Tan
2017-08-08 19:32 ` [RFC PATCH 04/10] pack: move open_pack_index(), parse_pack_index() Jonathan Tan
2017-08-08 20:19 ` Junio C Hamano
2017-08-08 20:45 ` Jonathan Tan
2017-08-08 19:32 ` [RFC PATCH 05/10] pack: move release_pack_memory() Jonathan Tan
2017-08-08 19:32 ` [RFC PATCH 06/10] pack: move pack-closing functions Jonathan Tan
2017-08-08 19:32 ` [RFC PATCH 07/10] pack: move use_pack() Jonathan Tan
2017-08-08 19:32 ` [RFC PATCH 08/10] pack: move unuse_pack() Jonathan Tan
2017-08-08 19:32 ` [RFC PATCH 09/10] pack: move add_packed_git() Jonathan Tan
2017-08-08 19:32 ` [RFC PATCH 10/10] pack: move install_packed_git() Jonathan Tan
2017-08-08 20:05 ` [RFC PATCH 00/10] An attempt to move packfile funcs to its own file Junio C Hamano
2017-08-08 20:43 ` Jonathan Tan
2017-08-08 21:04 ` Junio C Hamano
2017-08-09 1:22 ` [PATCH v2 00/25] Move exported " Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 01/25] pack: move pack name-related functions Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 02/25] pack: move static state variables Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 03/25] pack: move pack_report() Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 04/25] pack: move open_pack_index(), parse_pack_index() Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 05/25] pack: move release_pack_memory() Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 06/25] pack: move pack-closing functions Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 07/25] pack: move use_pack() Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 08/25] pack: move unuse_pack() Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 09/25] pack: move add_packed_git() Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 10/25] pack: move install_packed_git() Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 11/25] pack: move {,re}prepare_packed_git and approximate_object_count Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 12/25] pack: move unpack_object_header() Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 13/25] pack: move get_size_from_delta() Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 14/25] pack: move unpack_object_header() Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 15/25] sha1_file: set whence in storage-specific info fn Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 16/25] sha1_file: remove read_packed_sha1() Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 17/25] pack: move packed_object_info(), unpack_entry() Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 18/25] pack: move nth_packed_object_{sha1,oid} Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 19/25] pack: move check_pack_index_ptr(), nth_packed_object_offset() Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 20/25] pack: move find_pack_entry_one(), is_pack_valid() Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 21/25] pack: move find_sha1_pack() Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 22/25] pack: move find_pack_entry() and make it global Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 23/25] pack: move has_sha1_pack() Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 24/25] pack: move has_pack_index() Jonathan Tan
2017-08-09 1:22 ` [PATCH v2 25/25] pack: move for_each_packed_object() Jonathan Tan
2017-08-10 17:21 ` [PATCH v2 00/25] Move exported packfile funcs to its own file Stefan Beller
2017-08-10 21:19 ` Junio C Hamano
2017-08-10 21:59 ` Jonathan Tan
2017-08-10 22:40 ` Junio C Hamano
2017-08-11 20:36 ` [PATCH 0/2] non-move patches in preparation for packfile.c Jonathan Tan
2017-08-11 20:36 ` [PATCH 1/2] sha1_file: set whence in storage-specific info fn Jonathan Tan
2017-08-11 21:52 ` Junio C Hamano
2017-08-11 20:36 ` [PATCH 2/2] sha1_file: remove read_packed_sha1() Jonathan Tan
2017-08-11 22:06 ` Junio C Hamano [this message]
2017-08-11 19:41 ` [PATCH v2 00/25] Move exported packfile funcs to its own file Ben Peart
2017-08-18 23:36 ` Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 00/23] " Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 01/23] pack: move pack name-related functions Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 02/23] pack: move static state variables Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 03/23] pack: move pack_report() Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 04/23] pack: move open_pack_index(), parse_pack_index() Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 05/23] pack: move release_pack_memory() Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 06/23] pack: move pack-closing functions Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 07/23] pack: move use_pack() Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 08/23] pack: move unuse_pack() Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 09/23] pack: move add_packed_git() Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 10/23] pack: move install_packed_git() Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 11/23] pack: move {,re}prepare_packed_git and approximate_object_count Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 12/23] pack: move unpack_object_header_buffer() Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 13/23] pack: move get_size_from_delta() Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 14/23] pack: move unpack_object_header() Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 15/23] pack: move clear_delta_base_cache(), packed_object_info(), unpack_entry() Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 16/23] pack: move nth_packed_object_{sha1,oid} Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 17/23] pack: move check_pack_index_ptr(), nth_packed_object_offset() Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 18/23] pack: move find_pack_entry_one(), is_pack_valid() Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 19/23] pack: move find_sha1_pack() Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 20/23] pack: move find_pack_entry() and make it global Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 21/23] pack: move has_sha1_pack() Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 22/23] pack: move has_pack_index() Jonathan Tan
2017-08-18 22:20 ` [PATCH v3 23/23] pack: move for_each_packed_object() Jonathan Tan
2017-08-19 7:33 ` [PATCH v3 00/23] Move exported packfile funcs to its own file Junio C Hamano
2017-08-20 6:40 ` Junio C Hamano
2017-08-21 18:40 ` Jonathan Tan
2017-08-21 22:55 ` Junio C Hamano
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