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19 commits

Author SHA1 Message Date
Linus Torvalds bcbe5a515e Fix tree-walking compare_entry() in the presense of --prefix
When we make the "root" tree-walk info entry have a pathname in it, we
need to have a ->prev pointer so that compare_entry will actually notice
and traverse into the root.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-03-09 00:43:47 -08:00
Linus Torvalds 91e4f03604 Make 'traverse_trees()' traverse conflicting DF entries in parallel
This makes the traverse_trees() entry comparator routine use the more
relaxed form of name comparison that considers files and directories
with the same name identical.

We pass in a separate mask for just the directory entries, so that the
callback routine can decide (if it wants to) to only handle one or the
other type, but generally most (all?) users are expected to really want
to see the case of a name 'foo' showing up in one tree as a file and in
another as a directory at the same time.

In particular, moving 'unpack_trees()' over to use this tree traversal
mechanism requires this.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-03-09 00:43:47 -08:00
Linus Torvalds 5803c6f8a2 Add return value to 'traverse_tree()' callback
This allows the callback to return an error value, but it can also
specify which of the tree entries that it actually used up by returning
a positive mask value.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-03-09 00:43:47 -08:00
Linus Torvalds 40d934df72 Make 'traverse_tree()' use linked structure rather than 'const char *base'
This makes the calling convention a bit less obvious, but a lot more
flexible.  Instead of allocating and extending a new 'base' string, we
just link the top-most name into a linked list of the 'info' structure
when traversing a subdirectory, and we can generate the basename by
following the list.

Perhaps even more importantly, the linked list of info structures also
gives us a place to naturally save off other information than just the
directory name.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-03-09 00:43:47 -08:00
Martin Koegler 64cc1c0909 tree-walk: don't parse incorrect entries
The current code can access memory outside of the tree buffer in the
case of malformed tree entries.

This patch prevents this by:

 * The rest of the buffer must be at least 24 bytes (at least 1 byte
   mode, 1 blank, at least one byte path name, 1 NUL, 20 bytes sha1).

 * Check that the last NUL (21 bytes before the end) is present.
   This ensures that strlen() and get_mode() calls stay within the
   buffer.

 * The mode may not be empty. We have only to reject a blank at the
   begin, as the rest is handled by if (c < '0' || c > '7').

 * The blank is ensured by get_mode().

 * The path must contain at least one character.

Signed-off-by: Martin Koegler <mkoegler@auto.tuwien.ac.at>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-01-06 18:41:44 -08:00
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
Linus Torvalds 4651ece854 Switch over tree descriptors to contain a pre-parsed entry
This makes the tree descriptor contain a "struct name_entry" as part of
it, and it gets filled in so that it always contains a valid entry. On
some benchmarks, it improves performance by up to 15%.

That makes tree entry "extract" trivial, and means that we only actually
need to decode each tree entry just once: we decode the first one when
we initialize the tree descriptor, and each subsequent one when doing
"update_tree_entry()".  In particular, this means that we don't need to
do strlen() both at extract time _and_ at update time.

Finally, it also allows more sharing of code (entry_extract(), that
wanted a "struct name_entry", just got totally trivial, along with the
"tree_entry()" function).

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-03-21 11:15:26 -07:00
Linus Torvalds 6fda5e5180 Initialize tree descriptors with a helper function rather than by hand.
This removes slightly more lines than it adds, but the real reason for
doing this is that future optimizations will require more setup of the
tree descriptor, and so we want to do it in one place.

Also renamed the "desc.buf" field to "desc.buffer" just to trigger
compiler errors for old-style manual initializations, making sure I
didn't miss anything.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-03-21 10:21:57 -07:00
Linus Torvalds a8c40471ab Remove "pathlen" from "struct name_entry"
Since we have the "tree_entry_len()" helper function these days, and
don't need to do a full strlen(), there's no point in saving the path
length - it's just redundant information.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-03-21 10:21:56 -07:00
Linus Torvalds 304de2d2d6 Avoid unnecessary strlen() calls
This is a micro-optimization that grew out of the mailing list discussion
about "strlen()" showing up in profiles.

We used to pass regular C strings around to the low-level tree walking
routines, and while this worked fine, it meant that we needed to call
strlen() on strings that the caller always actually knew the size of
anyway.

So pass the length of the string down wih the string, and avoid
unnecessary calls to strlen(). Also, when extracting a pathname from a
tree entry, use "tree_entry_len()" instead of strlen(), since the length
of the pathname is directly calculable from the decoded tree entry itself
without having to actually do another strlen().

This shaves off another ~5-10% from some loads that are very tree
intensive (notably doing commit filtering by a pathspec).

Signed-off-by: Linus Torvalds  <torvalds@linux-foundation.org>"
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-03-18 15:36:59 -07:00
Jeff King d93b7d1c30 get_tree_entry: map blank requested entry to tree root
This means that
  git show HEAD:
will now return HEAD^{tree}, which is logically consistent with
  git show HEAD:Documentation

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-01-09 14:08:41 -08:00
René Scharfe 4fe2cc0c89 Remove shadowing variable from traverse_trees()
The variable named entry is allocated using malloc() and then
forgotten, it being shadowed by an automatic variable of the
same name.  Fixing the array size at 3 worked so far because
the only caller of traverse_trees() needed only as much
entries.  Simply remove the shadowing varaible and we're able
to traverse more than three trees and save stack space at the
same time!

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-01-04 22:28:46 -08:00
Shawn Pearce e702496e43 Convert memcpy(a,b,20) to hashcpy(a,b).
This abstracts away the size of the hash values when copying them
from memory location to memory location, much as the introduction
of hashcmp abstracted away hash value comparsion.

A few call sites were using char* rather than unsigned char* so
I added the cast rather than open hashcpy to be void*.  This is a
reasonable tradeoff as most call sites already use unsigned char*
and the existing hashcmp is also declared to be unsigned char*.

[jc: Splitted the patch to "master" part, to be followed by a
 patch for merge-recursive.c which is not in "master" yet.

 Fixed the cast in the latter hunk to combine-diff.c which was
 wrong in the original.

 Also converted ones left-over in combine-diff.c, diff-lib.c and
 upload-pack.c ]

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-08-23 13:53:10 -07:00
Florian Forster 1d7f171c3a Remove all void-pointer arithmetic.
ANSI C99 doesn't allow void-pointer arithmetic. This patch fixes this in
various ways. Usually the strategy that required the least changes was used.

Signed-off-by: Florian Forster <octo@verplant.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-06-20 01:59:46 -07:00
Linus Torvalds 4c068a9831 tree_entry(): new tree-walking helper function
This adds a "tree_entry()" function that combines the common operation of
doing a "tree_entry_extract()" + "update_tree_entry()".

It also has a simplified calling convention, designed for simple loops
that traverse over a whole tree: the arguments are pointers to the tree
descriptor and a name_entry structure to fill in, and it returns a boolean
"true" if there was an entry left to be gotten in the tree.

This allows tree traversal with

	struct tree_desc desc;
	struct name_entry entry;

	desc.buf = tree->buffer;
	desc.size = tree->size;
	while (tree_entry(&desc, &entry) {
		... use "entry.{path, sha1, mode, pathlen}" ...
	}

which is not only shorter than writing it out in full, it's hopefully less
error prone too.

[ It's actually a tad faster too - we don't need to recalculate the entry
  pathlength in both extract and update, but need to do it only once.
  Also, some callers can avoid doing a "strlen()" on the result, since
  it's returned as part of the name_entry structure.

  However, by now we're talking just 1% speedup on "git-rev-list --objects
  --all", and we're definitely at the point where tree walking is no
  longer the issue any more. ]

NOTE! Not everybody wants to use this new helper function, since some of
the tree walkers very much on purpose do the descriptor update separately
from the entry extraction. So the "extract + update" sequence still
remains as the core sequence, this is just a simplified interface.

We should probably add a silly two-line inline helper function for
initializing the descriptor from the "struct tree" too, just to cut down
on the noise from that common "desc" initializer.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-05-30 23:03:01 -07:00
Linus Torvalds 7d65848afd Don't use "sscanf()" for tree mode scanning
Doing an oprofile run on the result of my git rev-list memory leak fixes
and tree parsing cleanups, I was surprised by the third-highest entry
being

	samples  %        image name               app name                 symbol name
	179751    2.7163  libc-2.4.so              libc-2.4.so              _IO_vfscanf@@GLIBC_2.4

where that 2.7% is actually more than 5% of one CPU, because this was run
on a dual CPU setup with the other CPU just being idle.

That seems to all be from the use of 'sscanf(tree, "%o", &mode)' for the
tree buffer parsing.

So do the trivial octal parsing by hand, which also gives us where the
first space in the string is (and thus where the pathname starts) so we
can get rid of the "strchr(tree, ' ')" call too.

This brings the "git rev-list --all --objects" time down from 63 seconds
to 55 seconds on the historical kernel archive for me, so it's quite
noticeable - tree parsing is a lot of what we end up doing when following
all the objects.

[ I also see a 5% speedup on a full "git fsck-objects" on the current
  kernel archive, so that sscanf() really does seem to have hurt our
  performance by a surprising amount ]

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-05-28 19:39:49 -07:00
Junio C Hamano 4dcff634e6 get_tree_entry(): make it available from tree-walk
Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-04-19 14:05:47 -07:00
Peter Eriksen 8e44025925 Use blob_, commit_, tag_, and tree_type throughout.
This replaces occurences of "blob", "commit", "tag", and "tree",
where they're really used as type specifiers, which we already
have defined global constants for.

Signed-off-by: Peter Eriksen <s022018@student.dtu.dk>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-04-04 00:11:19 -07:00
Junio C Hamano 1b0c7174a1 tree/diff header cleanup.
Introduce tree-walk.[ch] and move "struct tree_desc" and
associated functions from various places.

Rename DIFF_FILE_CANON_MODE(mode) macro to canon_mode(mode) and
move it to cache.h.  This macro returns the canonicalized
st_mode value in the host byte order for files, symlinks and
directories -- to be compared with a tree_desc entry.
create_ce_mode(mode) in cache.h is similar but is intended to be
used for index entries (so it does not work for directories) and
returns the value in the network byte order.

Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-03-29 23:54:13 -08:00