1 files changed, 61 insertions, 0 deletions
diff --git a/lib/nghttp3_debug.c b/lib/nghttp3_debug.c
new file mode 100644
index 0000000..4021b0d
--- /dev/null
+++ b/lib/nghttp3_debug.c
@@ -0,0 +1,61 @@
+/*
+ * nghttp3
+ *
+ * Copyright (c) 2019 nghttp3 contributors
+ * Copyright (c) 2016 nghttp2 contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#include "nghttp3_debug.h"
+
+#include <stdio.h>
+
+#ifdef DEBUGBUILD
+
+static void nghttp3_default_debug_vfprintf_callback(const char *fmt,
+                                                    va_list args) {
+  vfprintf(stderr, fmt, args);
+}
+
+static nghttp3_debug_vprintf_callback static_debug_vprintf_callback =
+    nghttp3_default_debug_vfprintf_callback;
+
+void nghttp3_debug_vprintf(const char *format, ...) {
+  if (static_debug_vprintf_callback) {
+    va_list args;
+    va_start(args, format);
+    static_debug_vprintf_callback(format, args);
+    va_end(args);
+  }
+}
+
+void nghttp3_set_debug_vprintf_callback(
+    nghttp3_debug_vprintf_callback debug_vprintf_callback) {
+  static_debug_vprintf_callback = debug_vprintf_callback;
+}
+
+#else /* !DEBUGBUILD */
+
+void nghttp3_set_debug_vprintf_callback(
+    nghttp3_debug_vprintf_callback debug_vprintf_callback) {
+  (void)debug_vprintf_callback;
+}
+
+#endif /* !DEBUGBUILD */