diff options
Diffstat (limited to 'compat/snprintf.c')
| -rw-r--r-- | compat/snprintf.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/compat/snprintf.c b/compat/snprintf.c index 580966e56a..e1e0e7543d 100644 --- a/compat/snprintf.c +++ b/compat/snprintf.c @@ -2,12 +2,19 @@ /* * The size parameter specifies the available space, i.e. includes - * the trailing NUL byte; but Windows's vsnprintf expects the - * number of characters to write without the trailing NUL. + * 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) +#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) @@ -17,6 +24,8 @@ int git_vsnprintf(char *str, size_t maxsize, const char *format, va_list ap) if (maxsize > 0) { ret = vsnprintf(str, maxsize-SNPRINTF_SIZE_CORR, format, ap); + if (ret == maxsize-1) + ret = -1; /* Windows does not NUL-terminate if result fills buffer */ str[maxsize-1] = 0; } @@ -34,6 +43,8 @@ int git_vsnprintf(char *str, size_t maxsize, const char *format, va_list ap) break; s = str; ret = vsnprintf(str, maxsize-SNPRINTF_SIZE_CORR, format, ap); + if (ret == maxsize-1) + ret = -1; } free(s); return ret; |