#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;
+ int ret = -1;
- ret = vsnprintf(str, maxsize, format, ap);
+ if (maxsize > 0) {
+ ret = vsnprintf(str, maxsize-SNPRINTF_SIZE_CORR, format, ap);
+ /* Windows does not NUL-terminate if result fills buffer */
+ str[maxsize-1] = 0;
+ }
if (ret != -1)
return ret;
if (! str)
break;
s = str;
- ret = vsnprintf(str, maxsize, format, ap);
+ ret = vsnprintf(str, maxsize-SNPRINTF_SIZE_CORR, format, ap);
}
free(s);
return ret;