pfxlen can be longer than the path in objdir when relative_base
contains the path to gits object directory. Here we are interested
in checking if ent->base[] (the part that corresponds to .git/objects)
is the same string as objdir, and the code NUL-terminated ent->base[]
to
LEADING PATH\0XX/XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX\0
in preparation for these "duplicate check" step (before we return
from the function, the first NUL is turned into '/' so that we can
fill XX when probing for loose objects). All we need to do is to
compare the string with the path to our object directory.
Signed-off-by: Heiko Voigt <hvoigt@hvoigt.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When peeking into object stores of submodules, the code forgot that they
might borrow objects from alternate object stores on their own.
By Heiko Voigt
* hv/submodule-alt-odb:
teach add_submodule_odb() to look for alternates
Since we allow to link other object databases when loading a submodules
database we should also load possible alternates.
Signed-off-by: Heiko Voigt <hvoigt@hvoigt.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When write_loose_object() finds that it is unable to
create a temporary file, it complains, for instance:
unable to create temporary sha1 filename : Too many open files
That extra space was supposed to be the name of the file,
and will be an empty string if the git_mkstemps_mode() fails.
The name of the temporary file is unimportant; delete it.
Signed-off-by: Pete Wyckoff <pw@padd.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The error handling routines add a newline. Remove
the duplicate ones in error messages.
Signed-off-by: Pete Wyckoff <pw@padd.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Traditionally, all the callers of check_sha1_signature() first
called read_sha1_file() to prepare the whole object data in core,
and called this function. The function is used to revalidate what
we read from the object database actually matches the object name we
used to ask for the data from the object database.
Update the API to allow callers to pass NULL as the object data, and
have the function read and hash the object data using streaming API
to recompute the object name, without having to hold everything in
core at the same time. This is most useful in parse_object() that
parses a blob object, because this caller does not have to keep the
actual blob data around in memory after a "struct blob" is returned.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* jk/maint-avoid-streaming-filtered-contents:
do not stream large files to pack when filters are in use
teach dry-run convert_to_git not to require a src buffer
teach convert_to_git a "dry run" mode
* jk/maint-avoid-streaming-filtered-contents:
do not stream large files to pack when filters are in use
teach dry-run convert_to_git not to require a src buffer
teach convert_to_git a "dry run" mode
Because git's object format requires us to specify the
number of bytes in the object in its header, we must know
the size before streaming a blob into the object database.
This is not a problem when adding a regular file, as we can
get the size from stat(). However, when filters are in use
(such as autocrlf, or the ident, filter, or eol
gitattributes), we have no idea what the ultimate size will
be.
The current code just punts on the whole issue and ignores
filter configuration entirely for files larger than
core.bigfilethreshold. This can generate confusing results
if you use filters for large binary files, as the filter
will suddenly stop working as the file goes over a certain
size. Rather than try to handle unknown input sizes with
streaming, this patch just turns off the streaming
optimization when filters are in use.
This has a slight performance regression in a very specific
case: if you have autocrlf on, but no gitattributes, a large
binary file will avoid the streaming code path because we
don't know beforehand whether it will need conversion or
not. But if you are handling large binary files, you should
be marking them as such via attributes (or at least not
using autocrlf, and instead marking your text files as
such). And the flip side is that if you have a large
_non_-binary file, there is a correctness improvement;
before we did not apply the conversion at all.
The first half of the new t1051 script covers these failures
on input. The second half tests the matching output code
paths. These already work correctly, and do not need any
adjustment.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* nd/find-pack-entry-recent-cache-invalidation:
find_pack_entry(): do not keep packed_git pointer locally
sha1_file.c: move the core logic of find_pack_entry() into fill_pack_entry()
* nd/find-pack-entry-recent-cache-invalidation:
find_pack_entry(): do not keep packed_git pointer locally
sha1_file.c: move the core logic of find_pack_entry() into fill_pack_entry()
Since 3ba7a06552 (A loose object is not corrupt if it
cannot be read due to EMFILE), "git fsck" on a repository with an empty
loose object file complains with the error message
fatal: failed to read object <sha1>: Invalid argument
This comes from a failure of mmap on this empty file, which sets errno to
EINVAL. Instead of calling xmmap on empty file, we display a clean error
message ourselves, and return a NULL pointer. The new message is
error: object file .git/objects/09/<rest-of-sha1> is empty
fatal: loose object <sha1> (stored in .git/objects/09/<rest-of-sha1>) is corrupt
The second line was already there before the regression in 3ba7a06552,
and the first is an additional message, that should help diagnosing the
problem for the user.
Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Commit f7c22cc (always start looking up objects in the last used pack
first - 2007-05-30) introduce a static packed_git* pointer as an
optimization. The kept pointer however may become invalid if
free_pack_by_name() happens to free that particular pack.
Current code base does not access packs after calling
free_pack_by_name() so it should not be a problem. Anyway, move the
pointer out so that free_pack_by_name() can reset it to avoid running
into troubles in future.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The new helper function implements the logic to find the offset for the
object in one pack and fill a pack_entry structure. The next patch will
restructure the loop and will call the helper from two places.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
On Solaris the system headers define the "tmpfile" name, which'll
cause Git compiled with Sun Studio 12 Update 1 to whine about us
redefining the name:
"pack-write.c", line 76: warning: name redefined by pragma redefine_extname declared static: tmpfile (E_PRAGMA_REDEFINE_STATIC)
"sha1_file.c", line 2455: warning: name redefined by pragma redefine_extname declared static: tmpfile (E_PRAGMA_REDEFINE_STATIC)
"fast-import.c", line 858: warning: name redefined by pragma redefine_extname declared static: tmpfile (E_PRAGMA_REDEFINE_STATIC)
"builtin/index-pack.c", line 175: warning: name redefined by pragma redefine_extname declared static: tmpfile (E_PRAGMA_REDEFINE_STATIC)
Just renaming the "tmpfile" variable to "tmp_file" in the relevant
places is the easiest way to fix this.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* jc/stream-to-pack:
bulk-checkin: replace fast-import based implementation
csum-file: introduce sha1file_checkpoint
finish_tmp_packfile(): a helper function
create_tmp_packfile(): a helper function
write_pack_header(): a helper function
Conflicts:
pack.h
* nd/misc-cleanups:
unpack_object_header_buffer(): clear the size field upon error
tree_entry_interesting: make use of local pointer "item"
tree_entry_interesting(): give meaningful names to return values
read_directory_recursive: reduce one indentation level
get_tree_entry(): do not call find_tree_entry() on an empty tree
tree-walk.c: do not leak internal structure in tree_entry_len()
* nd/misc-cleanups:
unpack_object_header_buffer(): clear the size field upon error
tree_entry_interesting: make use of local pointer "item"
tree_entry_interesting(): give meaningful names to return values
read_directory_recursive: reduce one indentation level
get_tree_entry(): do not call find_tree_entry() on an empty tree
tree-walk.c: do not leak internal structure in tree_entry_len()
This extends the earlier approach to stream a large file directly from the
filesystem to its own packfile, and allows "git add" to send large files
directly into a single pack. Older code used to spawn fast-import, but the
new bulk-checkin API replaces it.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The callers do not use the returned size when the function says
it did not use any bytes and sets the type to OBJ_BAD, so this
should not matter in practice, but it is a good code hygiene
anyway.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* jk/maint-pack-objects-compete-with-delete:
downgrade "packfile cannot be accessed" errors to warnings
pack-objects: protect against disappearing packs
These can happen if another process simultaneously prunes a
pack. But that is not usually an error condition, because a
properly-running prune should have repacked the object into
a new pack. So we will notice that the pack has disappeared
unexpectedly, print a message, try other packs (possibly
after re-scanning the list of packs), and find it in the new
pack.
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It's possible that while pack-objects is running, a
simultaneously running prune process might delete a pack
that we are interested in. Because we load the pack indices
early on, we know that the pack contains our item, but by
the time we try to open and map it, it is gone.
Since c715f78, we already protect against this in the normal
object access code path, but pack-objects accesses the packs
at a lower level. In the normal access path, we call
find_pack_entry, which will call find_pack_entry_one on each
pack index, which does the actual lookup. If it gets a hit,
we will actually open and verify the validity of the
matching packfile (using c715f78's is_pack_valid). If we
can't open it, we'll issue a warning and pretend that we
didn't find it, causing us to go on to the next pack (or on
to loose objects).
Furthermore, we will cache the descriptor to the opened
packfile. Which means that later, when we actually try to
access the object, we are likely to still have that packfile
opened, and won't care if it has been unlinked from the
filesystem.
Notice the "likely" above. If there is another pack access
in the interim, and we run out of descriptors, we could
close the pack. And then a later attempt to access the
closed pack could fail (we'll try to re-open it, of course,
but it may have been deleted). In practice, this doesn't
happen because we tend to look up items and then access them
immediately.
Pack-objects does not follow this code path. Instead, it
accesses the packs at a much lower level, using
find_pack_entry_one directly. This means we skip the
is_pack_valid check, and may end up with the name of a
packfile, but no open descriptor.
We can add the same is_pack_valid check here. Unfortunately,
the access patterns of pack-objects are not quite as nice
for keeping lookup and object access together. We look up
each object as we find out about it, and the only later when
writing the packfile do we necessarily access it. Which
means that the opened packfile may be closed in the interim.
In practice, however, adding this check still has value, for
three reasons.
1. If you have a reasonable number of packs and/or a
reasonable file descriptor limit, you can keep all of
your packs open simultaneously. If this is the case,
then the race is impossible to trigger.
2. Even if you can't keep all packs open at once, you
may end up keeping the deleted one open (i.e., you may
get lucky).
3. The race window is shortened. You may notice early that
the pack is gone, and not try to access it. Triggering
the problem without this check means deleting the pack
any time after we read the list of index files, but
before we access the looked-up objects. Triggering it
with this check means deleting the pack means deleting
the pack after we do a lookup (and successfully access
the packfile), but before we access the object. Which
is a smaller window.
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When it needs to compare and add an alt object path to the
alt_odb_list, we normalize this path first since comparing normalized
path is easy to get correct result.
Use strbuf to replace some string operations, since it is cleaner and
safer.
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Hui Wang <Hui.Wang@windriver.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Cloning from a local repository blindly copies or hardlinks all the files
under objects/ hierarchy. This results in two issues:
- If the repository cloned has an "objects/info/alternates" file, and the
command line of clone specifies --reference, the ones specified on the
command line get overwritten by the copy from the original repository.
- An entry in a "objects/info/alternates" file can specify the object
stores it borrows objects from as a path relative to the "objects/"
directory. When cloning a repository with such an alternates file, if
the new repository is not sitting next to the original repository, such
relative paths needs to be adjusted so that they can be used in the new
repository.
This updates add_to_alternates_file() to take the path to the alternate
object store, including the "/objects" part at the end (earlier, it was
taking the path to $GIT_DIR and was adding "/objects" itself), as it is
technically possible to specify in objects/info/alternates file the path
of a directory whose name does not end with "/objects".
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git currently reports loose objects as 'corrupt' if they've been
deflated using a window size less than 32Kb, because the
experimental_loose_object() function doesn't recognise the header
byte as a zlib header. This patch makes the function tolerant of
all valid window sizes (15-bit to 8-bit) - but doesn't sacrifice
it's accuracy in distingushing the standard loose-object format
from the experimental (now abandoned) format.
On memory constrained systems zlib may use a much smaller window
size - working on Agit, I found that Android uses a 4KB window;
giving a header byte of 0x48, not 0x78. Consequently all loose
objects generated appear 'corrupt', which is why Agit is a read-only
Git client at this time - I don't want my client to generate Git
repos that other clients treat as broken :(
This patch makes Git tolerant of different deflate settings - it
might appear that it changes experimental_loose_object() to the point
where it could incorrectly identify the experimental format as the
standard one, but the two criteria (bitmask & checksum) can only
give a false result for an experimental object where both of the
following are true:
1) object size is exactly 8 bytes when uncompressed (bitmask)
2) [single-byte in-pack git type&size header] * 256
+ [1st byte of the following zlib header] % 31 = 0 (checksum)
As it happens, for all possible combinations of valid object type
(1-4) and window bits (0-7), the only time when the checksum will be
divisible by 31 is for 0x1838 - ie object type *1*, a Commit - which,
due the fields all Commit objects must contain, could never be as
small as 8 bytes in size.
Given this, the combination of the two criteria (bitmask & checksum)
always correctly determines the buffer format, and is more tolerant
than the previous version.
The alternative to this patch is simply removing support for the
experimental format, which I am also totally cool with.
References:
Android uses a 4KB window for deflation:
http://android.git.kernel.org/?p=platform/libcore.git;a=blob;f=luni/src/main/native/java_util_zip_Deflater.cpp;h=c0b2feff196e63a7b85d97cf9ae5bb2583409c28;hb=refs/heads/gingerbread#l53
Code snippet searching for false positives with the zlib checksum:
https://gist.github.com/1118177
Signed-off-by: Roberto Tyley <roberto.tyley@guardian.co.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* jc/index-pack:
verify-pack: use index-pack --verify
index-pack: show histogram when emulating "verify-pack -v"
index-pack: start learning to emulate "verify-pack -v"
index-pack: a miniscule refactor
index-pack --verify: read anomalous offsets from v2 idx file
write_idx_file: need_large_offset() helper function
index-pack: --verify
write_idx_file: introduce a struct to hold idx customization options
index-pack: group the delta-base array entries also by type
Conflicts:
builtin/verify-pack.c
cache.h
sha1_file.c
* jc/zlib-wrap:
zlib: allow feeding more than 4GB in one go
zlib: zlib can only process 4GB at a time
zlib: wrap deflateBound() too
zlib: wrap deflate side of the API
zlib: wrap inflateInit2 used to accept only for gzip format
zlib: wrap remaining calls to direct inflate/inflateEnd
zlib wrapper: refactor error message formatter
Conflicts:
sha1_file.c
In a workload other than "git log" (without pathspec nor any option that
causes us to inspect trees and blobs), the recency pack order is said to
cause the access jump around quite a bit. Add a hook to allow us observe
how bad it is.
"git config core.logpackaccess /var/tmp/pal.txt" will give you the log
in the specified file.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The size of objects we read from the repository and data we try to put
into the repository are represented in "unsigned long", so that on larger
architectures we can handle objects that weigh more than 4GB.
But the interface defined in zlib.h to communicate with inflate/deflate
limits avail_in (how many bytes of input are we calling zlib with) and
avail_out (how many bytes of output from zlib are we ready to accept)
fields effectively to 4GB by defining their type to be uInt.
In many places in our code, we allocate a large buffer (e.g. mmap'ing a
large loose object file) and tell zlib its size by assigning the size to
avail_in field of the stream, but that will truncate the high octets of
the real size. The worst part of this story is that we often pass around
z_stream (the state object used by zlib) to keep track of the number of
used bytes in input/output buffer by inspecting these two fields, which
practically limits our callchain to the same 4GB limit.
Wrap z_stream in another structure git_zstream that can express avail_in
and avail_out in unsigned long. For now, just die() when the caller gives
a size that cannot be given to a single zlib call. In later patches in the
series, we would make git_inflate() and git_deflate() internally loop to
give callers an illusion that our "improved" version of zlib interface can
operate on a buffer larger than 4GB in one go.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Wrap deflateInit, deflate, and deflateEnd for everybody, and the sole use
of deflateInit2 in remote-curl.c to tell the library to use gzip header
and trailer in git_deflate_init_gzip().
There is only one caller that cares about the status from deflateEnd().
Introduce git_deflate_end_gently() to let that sole caller retrieve the
status and act on it (i.e. die) for now, but we would probably want to
make inflate_end/deflate_end die when they ran out of memory and get
rid of the _gently() kind.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Every time I look at the read-loose-object codepath, legacy_loose_object()
function makes my brain go through mental contortion. When we were playing
with the experimental loose object format, it may have made sense to call
the traditional format "legacy", in the hope that the experimental one
will some day replace it to become official, but it never happened.
This renames the function (and negates its return value) to detect if we
are looking at the experimental format, and move the code around in its
caller which used to do "if we are looing at legacy, do this special case,
otherwise the normal case is this". The codepath to read from the loose
objects in experimental format is the "unlikely" case.
Someday after Git 2.0, we should drop the support of this format.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This finally gets rid of the inefficient verify-pack implementation that
walks objects in the packfile in their object name order and replaces it
with a call to index-pack --verify. As a side effect, it also removes
packed_object_info_detail() API which is rather expensive.
As this changes the way errors are reported (verify-pack used to rely on
the usual runtime error detection routine unpack_entry() to diagnose the
CRC errors in an entry in the *.idx file; index-pack --verify checks the
whole *.idx file in one go), update a test that expected the string "CRC"
to appear in the error message.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Using an unsigned type, we would fail to detect a read error and then
proceed to try to write (size_t)-1 bytes.
Signed-off-by: Jim Meyering <meyering@redhat.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* jc/bigfile:
Bigfile: teach "git add" to send a large file straight to a pack
index_fd(): split into two helper functions
index_fd(): turn write_object and format_check arguments into one flag
Make map_sha1_file(), parse_sha1_header() and unpack_sha1_header()
available to the streaming read API by exporting them via cache.h header
file.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
An object found in the delta-base cache is not guaranteed to
stay there, but we know it came from a pack and it is likely
to give us a quick access if we read_sha1_file() it right now,
which is a piece of useful information.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* jc/replacing:
read_sha1_file(): allow selective bypassing of replacement mechanism
inline lookup_replace_object() calls
read_sha1_file(): get rid of read_sha1_file_repl() madness
t6050: make sure we test not just commit replacement
Declare lookup_replace_object() in cache.h, not in commit.h
Conflicts:
environment.c
The original interface for sha1_object_info() takes an object name and
gives back a type and its size (the latter is given only when it was
asked). The new interface wraps its implementation and exposes a bit
more pieces of information that the interface used to discard, namely:
- where the object is stored (loose? cached? packed?)
- if packed, where in which packfile?
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
* In the earlier round, this used u.pack.delta to record the length of
the delta chain, but the caller is not necessarily interested in the
length of the delta chain per-se, but may only want to know if it is a
delta against another object or is stored as a deflated data. Calling
packed_object_info_detail() involves walking the reverse index chain to
compute the store size of the object and is unnecessarily expensive.
We could resurrect the code if a new caller wants to know, but I doubt
it.
