_snprintf() differs from snprintf() in:
* on overflow it returns -1 instead of required buffer size
* on overflow it does not fill nul byte
* does not accept NULL/0 as a buffer
Microsoft implemented snprintf() in Visual Studio 2015 as part of UCRT.
Mingw32 contains snprintf() implementation only when __USE_MINGW_ANSI_STDIO
is defined.
Mingw-w64 versions prior to 8.0.0. contain snprintf() implementation when
__USE_MINGW_ANSI_STDIO or _UCRT is defined. Since version 8.0.0 it is
always supported.
Mingw-w64 defines both __MINGW32__ and __MINGW64_VERSION_MAJOR macros.
Mingw32 defines only __MINGW32__.
_scprintf() just count number of bytes needed for formatting string, so it
is basically return value of snprintf().
This change updates miniupnpc code to use snprintf() when is provided by
compiler/runtime to avoid usage _snprintf().
And also this changes updates miniupnpc emulation of snprintf() by
_snprintf() and _scprintf() functions to avoid buffer overflows.
For inspiration full emulation of snprintf() by _snprintf() is available in
mingw-w64 stdio library:
https://sourceforge.net/p/mingw-w64/mingw-w64/ci/master/tree/mingw-w64-crt/stdio/snprintf.c
Details :
cast for connect() sendto() arguments
remove unecessary p = NULL;
remove unecessary code
printf format fixes in ssdpDiscoverDevices()
fixes#311
Signed-off-by: Thomas Bernard <miniupnp@free.fr>
Current code makes use of `snprintf` function defined in C99 standard
but _POSIX_C_SOURCE is set to "1" which is not correct. To access C99
definitions, this macro should be set to at least "200112L".
Also, `strncasecmp` function is being used but corresponding <strings.h>
header is not being included in miniwget.c.
Changes have been tested on FreeBSD 10.1 amd64 with default compiler
(Clang).
Pali Rohár
Thomas Bernard
irwir
Wladimir J. van der Laan
Mike Gelfand
Shawn Landen