winpty/shared/c99_snprintf.h
Ryan Prichard 41e7c31387 MSVC compatibility: Deal with snprintf and vsnprintf.
* When building with MSVC, there is no snprintf function, but there are
   _snprintf, vsnprintf, and _vsnprintf functions (as well as many
   variations on these).  The MSVC _snprintf is not the same as C99's
   snprintf, and in particular, it does not guarantee that the buffer is
   NUL-terminated, whereas C99 does guarantee this.  I want the C99
   behavior, so add a c99_[v]snprintf functions in shared/c99_snprintf.h
   that provide C99 behavior.

 * Details:
   http://stackoverflow.com/questions/2915672/snprintf-and-visual-studio-2010
2012-12-20 04:07:56 -08:00

88 lines
2.5 KiB
C

// Copyright (c) 2012 Ryan Prichard
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to
// deal in the Software without restriction, including without limitation the
// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
// sell copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
// IN THE SOFTWARE.
#ifndef C99_SNPRINTF_H
#define C99_SNPRINTF_H
#include <stdarg.h>
#include <stdio.h>
#ifdef _MSC_VER
/* MSVC does not define C99's va_copy, so define one for it. It appears that
* with MSVC, a va_list is a char*, not an array type, so va_copy is a simple
* assignment. On MSVC 2012, there is a VC/include/vadefs.h file defining
* va_list and the va_XXX routines, which has code for x86, x86-64, and ARM. */
#define c99_va_copy(dest, src) ((dest) = (src))
static inline int c99_vsnprintf(
char* str,
size_t size,
const char* format,
va_list ap)
{
va_list apcopy;
int count = -1;
if (size != 0) {
c99_va_copy(apcopy, ap);
count = _vsnprintf_s(str, size, _TRUNCATE, format, apcopy);
va_end(apcopy);
}
if (count == -1) {
c99_va_copy(apcopy, ap);
count = _vscprintf(format, apcopy);
va_end(apcopy);
}
return count;
}
#else
#define c99_va_copy(dest, src) (va_copy(dest, src))
static inline int c99_vsnprintf(
char* str,
size_t size,
const char* format,
va_list ap)
{
return vsnprintf(str, size, format, ap);
}
#endif /* _MSC_VER */
static inline int c99_snprintf(
char* str,
size_t size,
const char* format,
...)
{
int count;
va_list ap;
va_start(ap, format);
count = c99_vsnprintf(str, size, format, ap);
va_end(ap);
return count;
}
#endif /* C99_SNPRINTF_H */