/*
* 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)
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;
}
break;
s = str;
ret = vsnprintf(str, maxsize-SNPRINTF_SIZE_CORR, format, ap);
+ if (ret == maxsize-1)
+ ret = -1;
}
free(s);
return ret;