Commit Graph

7 Commits

Author SHA1 Message Date
Jeff King
a9bfbc5b69 compat/snprintf: don't look at va_list twice
If you define SNPRINTF_RETURNS_BOGUS, we use a special
git_vsnprintf wrapper assumes that vsnprintf returns "-1"
instead of the number of characters that you would need to
store the result.

To do this, it invokes vsnprintf multiple times, growing a
heap buffer until we have enough space to hold the result.
However, this means we evaluate the va_list parameter
multiple times, which is generally a bad thing (it may be
modified by calls to vsnprintf, yielding undefined
behavior).

Instead, we must va_copy it and hand the copy to vsnprintf,
so we always have a pristine va_list.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-12-12 09:09:35 -08:00
Frank Li
71064e3f86 Test for WIN32 instead of __MINGW32_
The code which is conditional on MinGW32 is actually conditional on Windows.
Use the WIN32 symbol, which is defined by the MINGW32 and MSVC environments,
but not by Cygwin.

Define SNPRINTF_SIZE_CORR=1 for MSVC too, as its vsnprintf function does
not add NUL at the end of the buffer if the result fits the buffer size
exactly.

Signed-off-by: Frank Li <lznuaa@gmail.com>
Signed-off-by: Marius Storm-Olsen <mstormo@gmail.com>
Acked-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-09-18 20:00:42 -07:00
Junio C Hamano
d1094fdd1b compat/snprintf.c: clarify SNPRINTF_SIZE_CORR
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-08-21 18:48:01 -07:00
Johannes Schindelin
f90cf2b920 MinGW: GCC >= 4 does not need SNPRINTF_SIZE_CORR anymore
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Steffen Prohaska <prohaska@zib.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-06-01 00:07:21 -07:00
Brandon Casey
a81892dd8c compat/snprintf.c: handle snprintf's that always return the # chars transmitted
Some platforms provide a horribly broken snprintf. More broken than the
platforms that return -1 when there is too little space in the target buffer
for the formatted string. Some platforms provide an snprintf which _always_
returns the number of characters transmitted to the buffer, regardless of
whether there was enough space or not.

IRIX 6.5 is such a platform. IRIX does have a working snprintf(), but it
is only provided when _NO_XOPEN5 evaluates to zero, and this only happens
if _XOPEN_SOURCE is defined, but definition of _XOPEN_SOURCE prevents
inclusion of many other common functions and defines. So it must be avoided.

Work around these horribly broken snprintf implementations by detecting an
snprintf call which results in the number of transmitted characters exactly
equal to the length of our buffer and retrying with a larger buffer just to
be safe.

Signed-off-by: Brandon Casey <casey@nrlssc.navy.mil>
Acked-by: Johannes Sixt <johannes.sixt@telecom.at>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-08-21 01:53:44 -07:00
Johannes Sixt
f4626df51f Add target architecture MinGW.
With this change GIT can be compiled and linked using MinGW. Builtins
that only read the repository such as the log family and grep already
work.

Simple stubs are provided for a number of functions that the Windows C
runtime does not offer. They will be completed in later patches.
However, a fix for the snprintf/vsnprintf replacement is applied here
to avoid buffer overflows.

Dmitry Kakurin pointed out that access(..., X_OK) would always fails on
Vista and suggested the -D__USE_MINGW_ACCESS workaround.

Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
2008-06-22 11:32:45 +02:00
Michal Rokos
c4582f93a2 Add compat/snprintf.c for systems that return bogus
Some systems (namely HPUX and Windows) return -1 when maxsize in snprintf()
and in vsnprintf() is reached. So replace snprintf() and vsnprintf()
functions with our own ones that return correct value upon overflow.

[jc: verified that review comments by J6t have been incorporated, and
 tightened the check to verify the resulting buffer contents, suggested
 by Wayne Davison]

Signed-off-by: Michal Rokos <michal.rokos@nextsoft.cz>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-03-05 13:12:07 -08:00