Support MSVC prior to 2015

1 files changed, 27 insertions, 0 deletions

diff --git a/upb/port.c b/upb/port.c
new file mode 100644
index 0000000..023f7dc
--- /dev/null
+++ b/upb/port.c
@@ -0,0 +1,27 @@
+
+#include "upb/upb.h"
+#include "upb/port_def.inc"
+
+#ifdef UPB_MSVC_VSNPRINTF
+/* Visual C++ earlier than 2015 doesn't have standard C99 snprintf and
+ * vsnprintf. To support them, missing functions are manually implemented
+ * using the existing secure functions. */
+int msvc_vsnprintf(char* s, size_t n, const char* format, va_list arg) {
+  if (!s) {
+    return _vscprintf(format, arg);
+  }
+  int ret = _vsnprintf_s(s, n, _TRUNCATE, format, arg);
+  if (ret < 0) {
+	ret = _vscprintf(format, arg);
+  }
+  return ret;
+}
+
+int msvc_snprintf(char* s, size_t n, const char* format, ...) {
+  va_list arg;
+  va_start(arg, format);
+  int ret = msvc_vsnprintf(s, n, format, arg);
+  va_end(arg);
+  return ret;
+}
+#endif