Commit Graph

316 Commits

Author SHA1 Message Date
Junio C Hamano
6eec46bdda fix sha1_pack_index_name()
An earlier commit 633f43e (Remove redundant code, eliminate one static
variable, 2008-05-24) had a thinko (perhaps an eyeno) that broke
sha1_pack_index_name() function.  One symptom of this was that the http
walker is now completely broken.

This should fix it.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-05-28 10:24:32 -07:00
Junio C Hamano
b84c343c88 Merge branch 'db/clone-in-c'
* db/clone-in-c:
  Add test for cloning with "--reference" repo being a subset of source repo
  Add a test for another combination of --reference
  Test that --reference actually suppresses fetching referenced objects
  clone: fall back to copying if hardlinking fails
  builtin-clone.c: Need to closedir() in copy_or_link_directory()
  builtin-clone: fix initial checkout
  Build in clone
  Provide API access to init_db()
  Add a function to set a non-default work tree
  Allow for having for_each_ref() list extra refs
  Have a constant extern refspec for "--tags"
  Add a library function to add an alternate to the alternates file
  Add a lockfile function to append to a file
  Mark the list of refs to fetch as const

Conflicts:

	cache.h
	t/t5700-clone-reference.sh
2008-05-25 13:41:37 -07:00
Heikki Orsila
633f43e1f7 Remove redundant code, eliminate one static variable
Signed-off-by: Heikki Orsila <heikki.orsila@iki.fi>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-05-24 22:05:06 -07:00
Nicolas Pitre
bbac73117e add a force_object_loose() function
This is meant to force the creation of a loose object even if it
already exists packed.  Needed for the next commit.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-05-13 22:42:33 -07:00
Daniel Barkalow
bef70b22ba Add a library function to add an alternate to the alternates file
This is in the core so that, if the alternates file has already been
read, the addition can be parsed and put into effect for the current
process.

Signed-off-by: Daniel Barkalow <barkalow@iabervon.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-05-04 17:41:44 -07:00
Heikki Orsila
c697ad143b Cleanup xread() loops to use read_in_full()
Signed-off-by: Heikki Orsila <heikki.orsila@iki.fi>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-05-03 22:15:25 -07:00
Junio C Hamano
628522ec14 sha1-lookup: more memory efficient search in sorted list of SHA-1
Currently, when looking for a packed object from the pack idx, a
simple binary search is used.

A conventional binary search loop looks like this:

        unsigned lo, hi;
        do {
                unsigned mi = (lo + hi) / 2;
                int cmp = "entry pointed at by mi" minus "target";
                if (!cmp)
                        return mi; "mi is the wanted one"
                if (cmp > 0)
                        hi = mi; "mi is larger than target"
                else
                        lo = mi+1; "mi is smaller than target"
        } while (lo < hi);
	"did not find what we wanted"

The invariants are:

  - When entering the loop, 'lo' points at a slot that is never
    above the target (it could be at the target), 'hi' points at
    a slot that is guaranteed to be above the target (it can
    never be at the target).

  - We find a point 'mi' between 'lo' and 'hi' ('mi' could be
    the same as 'lo', but never can be as high as 'hi'), and
    check if 'mi' hits the target.  There are three cases:

     - if it is a hit, we have found what we are looking for;

     - if it is strictly higher than the target, we set it to
       'hi', and repeat the search.

     - if it is strictly lower than the target, we update 'lo'
       to one slot after it, because we allow 'lo' to be at the
       target and 'mi' is known to be below the target.

    If the loop exits, there is no matching entry.

When choosing 'mi', we do not have to take the "middle" but
anywhere in between 'lo' and 'hi', as long as lo <= mi < hi is
satisfied.  When we somehow know that the distance between the
target and 'lo' is much shorter than the target and 'hi', we
could pick 'mi' that is much closer to 'lo' than (hi+lo)/2,
which a conventional binary search would pick.

This patch takes advantage of the fact that the SHA-1 is a good
hash function, and as long as there are enough entries in the
table, we can expect uniform distribution.  An entry that begins
with for example "deadbeef..." is much likely to appear much
later than in the midway of a reasonably populated table.  In
fact, it can be expected to be near 87% (222/256) from the top
of the table.

This is a work-in-progress and has switches to allow easier
experiments and debugging.  Exporting GIT_USE_LOOKUP environment
variable enables this code.

On my admittedly memory starved machine, with a partial KDE
repository (3.0G pack with 95M idx):

    $ GIT_USE_LOOKUP=t git log -800 --stat HEAD >/dev/null
    3.93user 0.16system 0:04.09elapsed 100%CPU (0avgtext+0avgdata 0maxresident)k
    0inputs+0outputs (0major+55588minor)pagefaults 0swaps

Without the patch, the numbers are:

    $ git log -800 --stat HEAD >/dev/null
    4.00user 0.15system 0:04.17elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k
    0inputs+0outputs (0major+60258minor)pagefaults 0swaps

In the same repository:

    $ GIT_USE_LOOKUP=t git log -2000 HEAD >/dev/null
    0.12user 0.00system 0:00.12elapsed 97%CPU (0avgtext+0avgdata 0maxresident)k
    0inputs+0outputs (0major+4241minor)pagefaults 0swaps

Without the patch, the numbers are:

    $ git log -2000 HEAD >/dev/null
    0.05user 0.01system 0:00.07elapsed 100%CPU (0avgtext+0avgdata 0maxresident)k
    0inputs+0outputs (0major+8506minor)pagefaults 0swaps

There isn't much time difference, but the number of minor faults
seems to show that we are touching much smaller number of pages,
which is expected.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-04-09 01:23:52 -07:00
Nicolas Pitre
70f5d5d31c fix unimplemented packed_object_info_detail() features
Since commit eb32d236df, there was a TODO
comment in packed_object_info_detail() about the SHA1 of base object to
OBJ_OFS_DELTA objects.  So here it is at last.

While at it, providing the actual storage size information as well is now
trivial.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-03-01 01:44:46 -08:00
Junio C Hamano
c484166374 Merge branch 'jk/empty-tree'
* jk/empty-tree:
  add--interactive: handle initial commit better
  hard-code the empty tree object
2008-02-20 16:13:28 -08:00
Junio C Hamano
ee4f06c0a6 Merge branch 'mk/maint-parse-careful'
* mk/maint-parse-careful:
  peel_onion: handle NULL
  check return value from parse_commit() in various functions
  parse_commit: don't fail, if object is NULL
  revision.c: handle tag->tagged == NULL
  reachable.c::process_tree/blob: check for NULL
  process_tag: handle tag->tagged == NULL
  check results of parse_commit in merge_bases
  list-objects.c::process_tree/blob: check for NULL
  reachable.c::add_one_tree: handle NULL from lookup_tree
  mark_blob/tree_uninteresting: check for NULL
  get_sha1_oneline: check return value of parse_object
  read_object_with_reference: don't read beyond the buffer
2008-02-18 20:56:01 -08:00
Martin Koegler
50974ec994 read_object_with_reference: don't read beyond the buffer
Signed-off-by: Martin Koegler <mkoegler@auto.tuwien.ac.at>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-02-18 19:20:17 -08:00
Jeff King
346245a1bb hard-code the empty tree object
Now any commands may reference the empty tree object by its
sha1 (4b825dc642). This is
useful for showing some diffs, especially for initial
commits.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-02-13 13:44:17 -08:00
Steffen Prohaska
21e5ad50fc safecrlf: Add mechanism to warn about irreversible crlf conversions
CRLF conversion bears a slight chance of corrupting data.
autocrlf=true will convert CRLF to LF during commit and LF to
CRLF during checkout.  A file that contains a mixture of LF and
CRLF before the commit cannot be recreated by git.  For text
files this is the right thing to do: it corrects line endings
such that we have only LF line endings in the repository.
But for binary files that are accidentally classified as text the
conversion can corrupt data.

If you recognize such corruption early you can easily fix it by
setting the conversion type explicitly in .gitattributes.  Right
after committing you still have the original file in your work
tree and this file is not yet corrupted.  You can explicitly tell
git that this file is binary and git will handle the file
appropriately.

Unfortunately, the desired effect of cleaning up text files with
mixed line endings and the undesired effect of corrupting binary
files cannot be distinguished.  In both cases CRLFs are removed
in an irreversible way.  For text files this is the right thing
to do because CRLFs are line endings, while for binary files
converting CRLFs corrupts data.

This patch adds a mechanism that can either warn the user about
an irreversible conversion or can even refuse to convert.  The
mechanism is controlled by the variable core.safecrlf, with the
following values:

 - false: disable safecrlf mechanism
 - warn: warn about irreversible conversions
 - true: refuse irreversible conversions

The default is to warn.  Users are only affected by this default
if core.autocrlf is set.  But the current default of git is to
leave core.autocrlf unset, so users will not see warnings unless
they deliberately chose to activate the autocrlf mechanism.

The safecrlf mechanism's details depend on the git command.  The
general principles when safecrlf is active (not false) are:

 - we warn/error out if files in the work tree can modified in an
   irreversible way without giving the user a chance to backup the
   original file.

 - for read-only operations that do not modify files in the work tree
   we do not not print annoying warnings.

There are exceptions.  Even though...

 - "git add" itself does not touch the files in the work tree, the
   next checkout would, so the safety triggers;

 - "git apply" to update a text file with a patch does touch the files
   in the work tree, but the operation is about text files and CRLF
   conversion is about fixing the line ending inconsistencies, so the
   safety does not trigger;

 - "git diff" itself does not touch the files in the work tree, it is
   often run to inspect the changes you intend to next "git add".  To
   catch potential problems early, safety triggers.

The concept of a safety check was originally proposed in a similar
way by Linus Torvalds.  Thanks to Dimitry Potapov for insisting
on getting the naked LF/autocrlf=true case right.

Signed-off-by: Steffen Prohaska <prohaska@zib.de>
2008-02-06 13:07:28 -08:00
Shawn O. Pearce
c9ced051c3 Fix random fast-import errors when compiled with NO_MMAP
fast-import was relying on the fact that on most systems mmap() and
write() are synchronized by the filesystem's buffer cache.  We were
relying on the ability to mmap() 20 bytes beyond the current end
of the file, then later fill in those bytes with a future write()
call, then read them through the previously obtained mmap() address.

This isn't always true with some implementations of NFS, but it is
especially not true with our NO_MMAP=YesPlease build time option used
on some platforms.  If fast-import was built with NO_MMAP=YesPlease
we used the malloc()+pread() emulation and the subsequent write()
call does not update the trailing 20 bytes of a previously obtained
"mmap()" (aka malloc'd) address.

Under NO_MMAP that behavior causes unpack_entry() in sha1_file.c to
be unable to read an object header (or data) that has been unlucky
enough to be written to the packfile at a location such that it
is in the trailing 20 bytes of a window previously opened on that
same packfile.

This bug has gone unnoticed for a very long time as it is highly data
dependent.  Not only does the object have to be placed at the right
position, but it also needs to be positioned behind some other object
that has been accessed due to a branch cache invalidation.  In other
words the stars had to align just right, and if you did run into
this bug you probably should also have purchased a lottery ticket.

Fortunately the workaround is a lot easier than the bug explanation.

Before we allow unpack_entry() to read data from a pack window
that has also (possibly) been modified through write() we force
all existing windows on that packfile to be closed.  By closing
the windows we ensure that any new access via the emulated mmap()
will reread the packfile, updating to the current file content.

This comes at a slight performance degredation as we cannot reuse
previously cached windows when we update the packfile.  But it
is a fairly minor difference as the window closes happen at only
two points:

 - When the packfile is finalized and its .idx is generated:

   At this stage we are getting ready to update the refs and any
   data access into the packfile is going to be random, and is
   going after only the branch tips (to ensure they are valid).
   Our existing windows (if any) are not likely to be positioned
   at useful locations to access those final tip commits so we
   probably were closing them before anyway.

 - When the branch cache missed and we need to reload:

   At this point fast-import is getting change commands for the next
   commit and it needs to go re-read a tree object it previously
   had written out to the packfile.  What windows we had (if any)
   are not likely to cover the tree in question so we probably were
   closing them before anyway.

We do try to avoid unnecessarily closing windows in the second case
by checking to see if the packfile size has increased since the
last time we called unpack_entry() on that packfile.  If the size
has not changed then we have not written additional data, and any
existing window is still vaild.  This nicely handles the cases where
fast-import is going through a branch cache reload and needs to read
many trees at once.  During such an event we are not likely to be
updating the packfile so we do not cycle the windows between reads.

With this change in place t9301-fast-export.sh (which was broken
by c3b0dec509) finally works again.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-01-17 22:39:20 -08:00
Jim Meyering
790296fd88 Fix grammar nits in documentation and in code comments.
Signed-off-by: Jim Meyering <meyering@redhat.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-01-03 09:15:17 -08:00
Steffen Prohaska
9e42d6a1c5 sha1_file.c: Fix size_t related printf format warnings
The old way of fixing warnings did not succeed on MinGW.  MinGW
does not support C99 printf format strings for size_t [1].  But
gcc on MinGW issues warnings if C99 printf format is not used.
Hence, the old stragegy to avoid warnings fails.

[1] http://www.mingw.org/MinGWiki/index.php/C99

This commits passes arguments of type size_t through a tiny
helper functions that casts to the type expected by the format
string.

Signed-off-by: Steffen Prohaska <prohaska@zib.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-11-28 16:03:38 -08:00
Johannes Sixt
85dadc3894 Use is_absolute_path() in sha1_file.c.
There are some places that test for an absolute path. Use the helper
function to ease porting.

Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-11-14 15:18:39 -08:00
Junio C Hamano
e2b7eaf0ca Merge branch 'maint'
* maint:
  RelNotes-1.5.3.5: describe recent fixes
  merge-recursive.c: mrtree in merge() is not used before set
  sha1_file.c: avoid gcc signed overflow warnings
  Fix a small memory leak in builtin-add
  honor the http.sslVerify option in shell scripts
2007-10-29 12:53:54 -07:00
Junio C Hamano
7109c889f1 sha1_file.c: avoid gcc signed overflow warnings
With the recent gcc, we get:

sha1_file.c: In check_packed_git_:
sha1_file.c:527: warning: assuming signed overflow does not
occur when assuming that (X + c) < X is always false
sha1_file.c:527: warning: assuming signed overflow does not
occur when assuming that (X + c) < X is always false

for a piece of code that tries to make sure that off_t is large
enough to hold more than 2^32 offset.  The test tried to make
sure these do not wrap-around:

    /* make sure we can deal with large pack offsets */
    off_t x = 0x7fffffffUL, y = 0xffffffffUL;
    if (x > (x + 1) || y > (y + 1)) {

but gcc assumes it can do whatever optimization it wants for a
signed overflow (undefined behaviour) and warns about this
construct.

Follow Linus's suggestion to check sizeof(off_t) instead to work
around the problem.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-10-29 11:56:57 -07:00
Junio C Hamano
66d4035e10 Merge branch 'ph/strbuf'
* ph/strbuf: (44 commits)
  Make read_patch_file work on a strbuf.
  strbuf_read_file enhancement, and use it.
  strbuf change: be sure ->buf is never ever NULL.
  double free in builtin-update-index.c
  Clean up stripspace a bit, use strbuf even more.
  Add strbuf_read_file().
  rerere: Fix use of an empty strbuf.buf
  Small cache_tree_write refactor.
  Make builtin-rerere use of strbuf nicer and more efficient.
  Add strbuf_cmp.
  strbuf_setlen(): do not barf on setting length of an empty buffer to 0
  sq_quote_argv and add_to_string rework with strbuf's.
  Full rework of quote_c_style and write_name_quoted.
  Rework unquote_c_style to work on a strbuf.
  strbuf API additions and enhancements.
  nfv?asprintf are broken without va_copy, workaround them.
  Fix the expansion pattern of the pseudo-static path buffer.
  builtin-for-each-ref.c::copy_name() - do not overstep the buffer.
  builtin-apply.c: fix a tiny leak introduced during xmemdupz() conversion.
  Use xmemdupz() in many places.
  ...
2007-10-03 03:06:02 -07:00
Pierre Habouzit
b315c5c081 strbuf change: be sure ->buf is never ever NULL.
For that purpose, the ->buf is always initialized with a char * buf living
in the strbuf module. It is made a char * so that we can sloppily accept
things that perform: sb->buf[0] = '\0', and because you can't pass "" as an
initializer for ->buf without making gcc unhappy for very good reasons.

strbuf_init/_detach/_grow have been fixed to trust ->alloc and not ->buf
anymore.

as a consequence strbuf_detach is _mandatory_ to detach a buffer, copying
->buf isn't an option anymore, if ->buf is going to escape from the scope,
and eventually be free'd.

API changes:
  * strbuf_setlen now always works, so just make strbuf_reset a convenience
    macro.
  * strbuf_detatch takes a size_t* optional argument (meaning it can be
    NULL) to copy the buffer's len, as it was needed for this refactor to
    make the code more readable, and working like the callers.

Signed-off-by: Pierre Habouzit <madcoder@debian.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-09-29 02:13:33 -07:00
Pierre Habouzit
182af8343c Use xmemdupz() in many places.
Signed-off-by: Pierre Habouzit <madcoder@debian.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-09-18 17:42:17 -07:00
Junio C Hamano
000dfd3f6e Export matches_pack_name() and fix its return value
The function sounds boolean; make it behave as one, not "0 for
success, non-zero for failure".

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-09-17 12:25:26 -07:00
Pierre Habouzit
ba3ed09728 Now that cache.h needs strbuf.h, remove useless includes.
Signed-off-by: Pierre Habouzit <madcoder@debian.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-09-16 17:30:03 -07:00
Pierre Habouzit
5ecd293d14 Rewrite convert_to_{git,working_tree} to use strbuf's.
* Now, those functions take an "out" strbuf argument, where they store their
  result if any. In that case, it also returns 1, else it returns 0.
* those functions support "in place" editing, in the sense that it's OK to
  call them this way:
    convert_to_git(path, sb->buf, sb->len, sb);
  When doable, conversions are done in place for real, else the strbuf
  content is just replaced with the new one, transparentely for the caller.

If you want to create a new filter working this way, being the accumulation
of filter1, filter2, ... filtern, then your meta_filter would be:

    int meta_filter(..., const char *src, size_t len, struct strbuf *sb)
    {
        int ret = 0;
        ret |= filter1(...., src, len, sb);
        if (ret) {
            src = sb->buf;
            len = sb->len;
        }
        ret |= filter2(...., src, len, sb);
        if (ret) {
            src = sb->buf;
            len = sb->len;
        }
        ....
        return ret | filtern(..., src, len, sb);
    }

That's why subfilters the convert_to_* functions called were also rewritten
to work this way.

Signed-off-by: Pierre Habouzit <madcoder@debian.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-09-16 17:30:03 -07:00
Pierre Habouzit
fd17f5b5f7 Replace all read_fd use with strbuf_read, and get rid of it.
This brings builtin-stripspace, builtin-tag and mktag to use strbufs.

Signed-off-by: Pierre Habouzit <madcoder@debian.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-09-10 12:50:58 -07:00
Shawn O. Pearce
9064d87b06 Don't segfault if we failed to inflate a packed delta
Under some types of packfile corruption the zlib stream holding the
data for a delta within a packfile may fail to inflate, due to say
a CRC failure within the compressed data itself.  When this occurs
the unpack_compressed_entry function will return NULL as a signal to
the caller that the data is not available.  Unfortunately we then
tried to use that NULL as though it referenced a memory location
where a delta was stored and tried to apply it to the delta base.
Loading a byte from the NULL address typically causes a SIGSEGV.

cate on #git noticed this failure in `git fsck --full` where the
call to verify_pack() first noticed that the packfile was corrupt
by finding that the packfile's SHA-1 did not match the raw data of
the file.  After finding this fsck went ahead and tried to verify
every object within the packfile, even though the packfile was
already known to be bad.  If we are going to shovel bad data at
the delta unpacking code, we better handle it correctly.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-08-25 08:33:47 -07:00
Luiz Fernando N. Capitulino
eef427a09c Avoid ambiguous error message if pack.idx header is wrong
Print the index version when an error occurs so the user
knows what type of header (and size) we thought the index
should have had.

Signed-off-by: Luiz Fernando N. Capitulino <lcapitulino@mandriva.com.br>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-08-14 22:20:13 -07:00
Carlos Rica
c4fba0a358 Rename read_pipe() with read_fd() and make its buffer nul-terminated.
The new name is closer to the purpose of the function.

A NUL-terminated buffer makes things easier when callers need that.
Since the function returns only the memory written with data,
almost always allocating more space than needed because final
size is unknown, an extra NUL terminating the buffer is harmless.
It is not included in the returned size, so the function
remains working as before.

Also, now the function allows the buffer passed to be NULL at first,
and alloc_nr is now used for growing the buffer, instead size=*2.

Signed-off-by: Carlos Rica <jasampler@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-07-18 17:30:03 -07:00
Junio C Hamano
e2b1accc59 Merge branch 'maint'
* maint:
  Document -<n> for git-format-patch
  glossary: add 'reflog'
  diff --no-index: fix --name-status with added files
  Don't smash stack when $GIT_ALTERNATE_OBJECT_DIRECTORIES is too long
2007-07-03 22:56:59 -07:00
Jim Meyering
9cb18f56fd Don't smash stack when $GIT_ALTERNATE_OBJECT_DIRECTORIES is too long
There is no restriction on the length of the name returned by
get_object_directory, other than the fact that it must be a stat'able
git object directory.  That means its name may have length up to
PATH_MAX-1 (i.e., often 4095) not counting the trailing NUL.

Combine that with the assumption that the concatenation of that name and
suffixes like "/info/alternates" and "/pack/---long-name---.idx" will fit
in a buffer of length PATH_MAX, and you see the problem.  Here's a fix:

    sha1_file.c (prepare_packed_git_one): Lengthen "path" buffer
    so we are guaranteed to be able to append "/pack/" without checking.
    Skip any directory entry that is too long to be appended.
    (read_info_alternates): Protect against a similar buffer overrun.

Before this change, using the following admittedly contrived environment
setting would cause many git commands to clobber their stack and segfault
on a system with PATH_MAX == 4096:

  t=$(perl -e '$s=".git/objects";$n=(4096-6-length($s))/2;print "./"x$n . $s')
  export GIT_ALTERNATE_OBJECT_DIRECTORIES=$t
  touch g
  ./git-update-index --add g

If you run the above commands, you'll soon notice that many
git commands now segfault, so you'll want to do this:

  unset GIT_ALTERNATE_OBJECT_DIRECTORIES

Signed-off-by: Jim Meyering <jim@meyering.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-07-03 12:25:29 -07:00
Junio C Hamano
68fb465049 Merge branch 'maint'
* maint:
  config: Change output of --get-regexp for valueless keys
  config: Complete documentation of --get-regexp
  cleanup merge-base test script
  Fix zero-object version-2 packs
  Ignore submodule commits when fetching over dumb protocols
2007-06-26 18:45:29 -07:00
Linus Torvalds
1164f1e48d Fix zero-object version-2 packs
A pack-file can get created without any objects in it (to transfer "no
data" - which can happen if you use a reference git repo, for example,
or just otherwise just end up transferring only branch head information
and already have all the objects themselves).

And while we probably should never create an index for such a pack, if we
do (and we do), the index file size sanity checking was incorrect.

This fixes it.

Reported-and-tested-by: Jocke Tjernlund <tjernlund@tjernlund.se>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-06-26 18:02:15 -07:00
Junio C Hamano
4175e9e3a8 More static
There still are quite a few symbols that ought to be static.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-06-13 02:02:10 -07:00
Junio C Hamano
b79d18c92d -Wold-style-definition fix
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-06-13 02:02:10 -07:00
Junio C Hamano
a6080a0a44 War on whitespace
This uses "git-apply --whitespace=strip" to fix whitespace errors that have
crept in to our source files over time.  There are a few files that need
to have trailing whitespaces (most notably, test vectors).  The results
still passes the test, and build result in Documentation/ area is unchanged.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-06-07 00:04:01 -07:00
Junio C Hamano
17c2929aa2 Merge branch 'sp/pack'
* sp/pack:
  Style nit - don't put space after function names
  Ensure the pack index is opened before access
  Simplify index access condition in count-objects, pack-redundant
  Test for recent rev-parse $abbrev_sha1 regression
  rev-parse: Identify short sha1 sums correctly.
  Attempt to delay prepare_alt_odb during get_sha1
  Micro-optimize prepare_alt_odb
  Lazily open pack index files on demand
2007-06-02 12:18:51 -07:00
Junio C Hamano
bd724be4be Merge branch 'maint'
* maint:
  git-config: Improve documentation of git-config file handling
  git-config: Various small fixes to asciidoc documentation
  decode_85(): fix missing return.
  fix signed range problems with hex conversions
2007-05-31 00:15:14 -07:00
Junio C Hamano
8e29f903eb Merge branch 'maint-1.5.1' into maint
* maint-1.5.1:
  git-config: Improve documentation of git-config file handling
  git-config: Various small fixes to asciidoc documentation
  decode_85(): fix missing return.
  fix signed range problems with hex conversions
2007-05-31 00:09:26 -07:00
Nicolas Pitre
f7c22cc68c always start looking up objects in the last used pack first
Jon Smirl said:

| Once an object reference hits a pack file it is very likely that
| following references will hit the same pack file. So first place to
| look for an object is the same place the previous object was found.

This is indeed a good heuristic so here it is.  The search always start
with the pack where the last object lookup succeeded.  If the wanted
object is not available there then the search continues with the normal
pack ordering.

To test this I split the Linux repository into 66 packs and performed a
"time git-rev-list --objects --all > /dev/null".  Best results are as
follows:

	Pack Sort			w/o this patch	w/ this patch
	-------------------------------------------------------------
	recent objects last		26.4s		20.9s
	recent objects first		24.9s		18.4s

This shows that the pack order based on object age has some influence,
but that the last-used-pack heuristic is even more significant in
reducing object lookup.

Signed-off-by: Nicolas Pitre <nico@cam.org> --- Note: the
--max-pack-size to git-repack currently produces packs with old objects
after those containing recent objects.  The pack sort based on
filesystem timestamp is therefore backward for those.  This needs to be
fixed of course, but at least it made me think about this variable for
the test.
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-05-30 23:35:07 -07:00
Linus Torvalds
192a6be2a7 fix signed range problems with hex conversions
Make hexval_table[] "const".  Also make sure that the accessor
function hexval() does not access the table with out-of-range
values by declaring its parameter "unsigned char", instead of
"unsigned int".

With this, gcc can just generate:

	movzbl  (%rdi), %eax
	movsbl  hexval_table(%rax),%edx
	movzbl  1(%rdi), %eax
	movsbl  hexval_table(%rax),%eax
	sall    $4, %edx
	orl     %eax, %edx

for the code to generate a byte from two hex characters.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-05-30 15:01:37 -07:00
Shawn O. Pearce
bc8e478a28 Style nit - don't put space after function names
Our style is to not put a space after a function name.  I did here,
and Junio applied the patch with the incorrect formatting.  So I'm
cleaning up after myself since I noticed it upon review.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-05-29 23:31:19 -07:00
Shawn O. Pearce
7dc24aa5a6 Micro-optimize prepare_alt_odb
Calling getenv() is not that expensive, but its also not free,
and its certainly not cheaper than testing to see if alt_odb_tail
is not null.

Because we are calling prepare_alt_odb() from within find_sha1_file
every time we cannot find an object file locally we want to skip out
of prepare_alt_odb() as early as possible once we have initialized
our alternate list.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-05-26 20:28:08 -07:00
Shawn O. Pearce
d079837eee Lazily open pack index files on demand
In some repository configurations the user may have many packfiles,
but all of the recent commits/trees/tags/blobs are likely to
be in the most recent packfile (the one with the newest mtime).
It is therefore common to be able to complete an entire operation
by accessing only one packfile, even if there are 25 packfiles
available to the repository.

Rather than opening and mmaping the corresponding .idx file for
every pack found, we now only open and map the .idx when we suspect
there might be an object of interest in there.

Of course we cannot known in advance which packfile contains an
object, so we still need to scan the entire packed_git list to
locate anything.  But odds are users want to access objects in the
most recently created packfiles first, and that may be all they
ever need for the current operation.

Junio observed in b867092f that placing recent packfiles before
older ones can slightly improve access times for recent objects,
without degrading it for historical object access.

This change improves upon Junio's observations by trying even harder
to avoid the .idx files that we won't need.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-05-26 20:28:08 -07:00
Junio C Hamano
cc93020f52 Merge branch 'np/pack'
* np/pack:
  deprecate the new loose object header format
  make "repack -f" imply "pack-objects --no-reuse-object"
  allow for undeltified objects not to be reused
2007-05-20 02:18:43 -07:00
Johan Herland
8a912bcb25 Ensure return value from xread() is always stored into an ssize_t
This patch fixes all calls to xread() where the return value is not
stored into an ssize_t. The patch should not have any effect whatsoever,
other than putting better/more appropriate type names on variables.

Signed-off-by: Johan Herland <johan@herland.net>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-05-15 21:16:03 -07:00
Nicolas Pitre
726f852b0e deprecate the new loose object header format
Now that we encourage and actively preserve objects in a packed form
more agressively than we did at the time the new loose object format and
core.legacyheaders were introduced, that extra loose object format
doesn't appear to be worth it anymore.

Because the packing of loose objects has to go through the delta match
loop anyway, and since most of them should end up being deltified in
most cases, there is really little advantage to have this parallel loose
object format as the CPU savings it might provide is rather lost in the
noise in the end.

This patch gets rid of core.legacyheaders, preserve the legacy format as
the only writable loose object format and deprecate the other one to
keep things simpler.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-05-10 15:22:33 -07:00
Junio C Hamano
6169a89c4f Merge branch 'maint'
* maint:
  Start preparing for 1.5.1.3
  Sanitize @to recipients.
  git-svn: Ignore usernames in URLs in find_by_url
  Document --dry-run and envelope-sender for git-send-email.
  Allow users to optionally specify their envelope sender.
  Ensure clean addresses are always used with Net::SMTP
  Validate @recipients before using it for sendmail and Net::SMTP.
  Perform correct quoting of recipient names.
  Change the scope of the $cc variable as it is not needed outside of send_message.
  Debugging cleanup improvements
  Prefix Dry- to the message status to denote dry-runs.
  Document --dry-run parameter to send-email.
  git-svn: Don't rely on $_ after making a function call
  Fix handle leak in write_tree
  Actually handle some-low memory conditions

Conflicts:

	RelNotes
	git-send-email.perl
2007-04-25 23:31:45 -07:00
Shawn O. Pearce
d1efefa46f Actually handle some-low memory conditions
Tim Ansell discovered his Debian server didn't permit git-daemon to
use as much memory as it needed to handle cloning a project with
a 128 MiB packfile.  Filtering the strace provided by Tim of the
rev-list child showed this gem of a sequence:

  open("./objects/pack/pack-*.pack", O_RDONLY|O_LARGEFILE <unfinished ...>
  <... open resumed> )              = 5

OK, so the packfile is fd 5...

  mmap2(NULL, 33554432, PROT_READ, MAP_PRIVATE, 5, 0 <unfinished ...>
   <... mmap2 resumed> )             = 0xb5e2d000

and we mapped one 32 MiB window from it at position 0...

   mmap2(NULL, 31020635, PROT_READ, MAP_PRIVATE, 5, 0x6000 <unfinished ...>
   <... mmap2 resumed> )             = -1 ENOMEM (Cannot allocate memory)

And we asked for another window further into the file.  But got
denied.  In Tim's case this was due to a resource limit on the
git-daemon process, and its children.

Now where are we in the code?  We're down inside use_pack(),
after we have called unuse_one_window() enough times to make sure
we stay within our allowed maximum window size.  However since we
didn't unmap the prior window at 0xb5e2d000 we aren't exceeding
the current limit (which probably was just the defaults).

But we're actually down inside xmmap()...

So we release the window we do have (by calling release_pack_memory),
assuming there is some memory pressure...

   munmap(0xb5e2d000, 33554432 <unfinished ...>
   <... munmap resumed> )            = 0
   close(5 <unfinished ...>
   <... close resumed> )             = 0

And that was the last window in this packfile.  So we closed it.
Way to go us.  Our xmmap did not expect release_pack_memory to
close the fd its about to map...

   mmap2(NULL, 31020635, PROT_READ, MAP_PRIVATE, 5, 0x6000 <unfinished ...>
   <... mmap2 resumed> )             = -1 EBADF (Bad file descriptor)

And so the Linux kernel happily tells us f' off.

   write(2, "fatal: ", 7 <unfinished ...>
   <... write resumed> )             = 7
   write(2, "Out of memory? mmap failed: Bad "..., 47 <unfinished ...>
   <... write resumed> )             = 47

And we report the bad file descriptor error, and not the ENOMEM,
and die, claiming we are out of memory.  But actually that mmap
should have succeeded, as we had enough memory for that window,
seeing as how we released the prior one.

Originally when I developed the sliding window mmap feature I had
this exact same bug in fast-import, and I dealt with it by handing
in the struct packed_git* we want to open the new window for, as the
caller wasn't prepared to reopen the packfile if unuse_one_window
closed it.  The same is true here from xmmap, but the caller doesn't
have the struct packed_git* handy.  So I'm using the file descriptor
instead to perform the same test.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-04-25 14:22:24 -07:00
Junio C Hamano
a2d7c6c620 Merge branch 'jc/attr'
* 'jc/attr': (28 commits)
  lockfile: record the primary process.
  convert.c: restructure the attribute checking part.
  Fix bogus linked-list management for user defined merge drivers.
  Simplify calling of CR/LF conversion routines
  Document gitattributes(5)
  Update 'crlf' attribute semantics.
  Documentation: support manual section (5) - file formats.
  Simplify code to find recursive merge driver.
  Counto-fix in merge-recursive
  Fix funny types used in attribute value representation
  Allow low-level driver to specify different behaviour during internal merge.
  Custom low-level merge driver: change the configuration scheme.
  Allow the default low-level merge driver to be configured.
  Custom low-level merge driver support.
  Add a demonstration/test of customized merge.
  Allow specifying specialized merge-backend per path.
  merge-recursive: separate out xdl_merge() interface.
  Allow more than true/false to attributes.
  Document git-check-attr
  Change attribute negation marker from '!' to '-'.
  ...
2007-04-21 17:38:00 -07:00