diff options
Diffstat (limited to 'compat/snprintf.c')
| -rw-r--r-- | compat/snprintf.c | 25 |
1 files changed, 21 insertions, 4 deletions
diff --git a/compat/snprintf.c b/compat/snprintf.c index dbfc2d6b6e..357e733074 100644 --- a/compat/snprintf.c +++ b/compat/snprintf.c @@ -1,12 +1,27 @@ #include "../git-compat-util.h" +/* + * 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. + */ +#ifndef SNPRINTF_SIZE_CORR +#define SNPRINTF_SIZE_CORR 0 +#endif + #undef vsnprintf int git_vsnprintf(char *str, size_t maxsize, const char *format, va_list ap) { char *s; - int ret; - - ret = vsnprintf(str, maxsize, format, ap); + int ret = -1; + + 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; + } if (ret != -1) return ret; @@ -20,7 +35,9 @@ int git_vsnprintf(char *str, size_t maxsize, const char *format, va_list ap) if (! str) break; s = str; - ret = vsnprintf(str, maxsize, format, ap); + ret = vsnprintf(str, maxsize-SNPRINTF_SIZE_CORR, format, ap); + if (ret == maxsize-1) + ret = -1; } free(s); return ret; |