diff options
Diffstat (limited to 'compat/snprintf.c')
| -rw-r--r-- | compat/snprintf.c | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/compat/snprintf.c b/compat/snprintf.c new file mode 100644 index 000000000000..0b1168853778 --- /dev/null +++ b/compat/snprintf.c @@ -0,0 +1,69 @@ +#include "../git-compat-util.h" + +/* + * The size parameter specifies the available space, i.e. includes + * the trailing NUL byte; but Windows's vsnprintf uses the entire + * buffer and avoids the trailing NUL, should the buffer be exactly + * big enough for the result. Defining SNPRINTF_SIZE_CORR to 1 will + * therefore remove 1 byte from the reported buffer size, so we + * always have room for a trailing NUL byte. + */ +#ifndef SNPRINTF_SIZE_CORR +#if defined(WIN32) && (!defined(__GNUC__) || __GNUC__ < 4) && (!defined(_MSC_VER) || _MSC_VER < 1900) +#define SNPRINTF_SIZE_CORR 1 +#else +#define SNPRINTF_SIZE_CORR 0 +#endif +#endif + +#undef vsnprintf +int git_vsnprintf(char *str, size_t maxsize, const char *format, va_list ap) +{ + va_list cp; + char *s; + int ret = -1; + + if (maxsize > 0) { + va_copy(cp, ap); + ret = vsnprintf(str, maxsize-SNPRINTF_SIZE_CORR, format, cp); + va_end(cp); + if (ret == maxsize-1) + ret = -1; + /* Windows does not NUL-terminate if result fills buffer */ + str[maxsize-1] = 0; + } + if (ret != -1) + return ret; + + s = NULL; + if (maxsize < 128) + maxsize = 128; + + while (ret == -1) { + maxsize *= 4; + str = realloc(s, maxsize); + if (! str) + break; + s = str; + va_copy(cp, ap); + ret = vsnprintf(str, maxsize-SNPRINTF_SIZE_CORR, format, cp); + va_end(cp); + if (ret == maxsize-1) + ret = -1; + } + free(s); + return ret; +} + +int git_snprintf(char *str, size_t maxsize, const char *format, ...) +{ + va_list ap; + int ret; + + va_start(ap, format); + ret = git_vsnprintf(str, maxsize, format, ap); + va_end(ap); + + return ret; +} + |