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5 commits

Author SHA1 Message Date
brian m. carlson aa1c6fdf47 define utility functions for object IDs
There are several utility functions (hashcmp and friends) that are used
for comparing object IDs (SHA-1 values).  Using these functions, which
take pointers to unsigned char, with struct object_id requires tiresome
access to the sha1 member, which bloats code and violates the desired
encapsulation.  Provide wrappers around these functions for struct
object_id for neater, more maintainable code.  Use the new constants to
avoid the hard-coded 20s and 40s throughout the original functions.

These functions simply call the underlying pointer-to-unsigned-char
versions to ensure that any performance improvements will be passed
through to the new functions.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-03-13 22:43:11 -07:00
Junio C Hamano 552f6994d2 Merge branch 'sb/hex-object-name-is-at-most-41-bytes-long' into maint
Code clean-up.

* sb/hex-object-name-is-at-most-41-bytes-long:
  hex.c: reduce memory footprint of sha1_to_hex static buffers
2015-03-05 13:12:55 -08:00
Stefan Beller 0b868f0eec hex.c: reduce memory footprint of sha1_to_hex static buffers
41 bytes is the exact number of bytes needed for having the returned
hex string represented. 50 seems to be an arbitrary number, such
that there are no benefits from alignment to certain address boundaries.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-02-13 13:42:17 -08:00
Michael Haggerty d4e85a1afe get_sha1_hex(): do not read past a NUL character
Previously, get_sha1_hex() would read one character past the end of a
null-terminated string whose strlen was an even number less than 40.
Although the function correctly returned -1 in these cases, the extra
memory access might have been to uninitialized (or even, conceivably,
unallocated) memory.

Add a check to avoid reading past the end of a string.

This problem was discovered by Thomas Rast <trast@student.ethz.ch>
using valgrind.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-10-05 13:45:16 -07:00
Linus Torvalds a5031214c4 slim down "git show-index"
As the documentation says, this is primarily for debugging, and
in the longer term we should rename it to test-show-index or something.

In the meantime, just avoid xmalloc (which slurps in the rest of git), and
separating out the trivial hex functions into "hex.o".

This results in

  [torvalds@nehalem git]$ size git-show-index
       text    data     bss     dec     hex filename
     222818    2276  112688  337782   52776 git-show-index (before)
       5696     624    1264    7584    1da0 git-show-index (after)

which is a whole lot better.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-01-21 20:03:45 -08:00