1 files changed, 70 insertions, 0 deletions
diff --git a/lib/nghttp2_alpn.c b/lib/nghttp2_alpn.c
new file mode 100644
index 0000000..33c5885
--- /dev/null
+++ b/lib/nghttp2_alpn.c
@@ -0,0 +1,70 @@
+/*
+ * nghttp2 - HTTP/2 C Library
+ *
+ * Copyright (c) 2012 Tatsuhiro Tsujikawa
+ *
+ * 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 "nghttp2_alpn.h"
+
+#include <string.h>
+
+static int select_alpn(const unsigned char **out, unsigned char *outlen,
+                       const unsigned char *in, unsigned int inlen,
+                       const char *key, unsigned int keylen) {
+  unsigned int i;
+  for (i = 0; i + keylen <= inlen; i += (unsigned int)(in[i] + 1)) {
+    if (memcmp(&in[i], key, keylen) == 0) {
+      *out = (unsigned char *)&in[i + 1];
+      *outlen = in[i];
+      return 0;
+    }
+  }
+  return -1;
+}
+
+#define NGHTTP2_HTTP_1_1_ALPN "\x8http/1.1"
+#define NGHTTP2_HTTP_1_1_ALPN_LEN (sizeof(NGHTTP2_HTTP_1_1_ALPN) - 1)
+
+int nghttp2_select_next_protocol(unsigned char **out, unsigned char *outlen,
+                                 const unsigned char *in, unsigned int inlen) {
+  if (select_alpn((const unsigned char **)out, outlen, in, inlen,
+                  NGHTTP2_PROTO_ALPN, NGHTTP2_PROTO_ALPN_LEN) == 0) {
+    return 1;
+  }
+  if (select_alpn((const unsigned char **)out, outlen, in, inlen,
+                  NGHTTP2_HTTP_1_1_ALPN, NGHTTP2_HTTP_1_1_ALPN_LEN) == 0) {
+    return 0;
+  }
+  return -1;
+}
+
+int nghttp2_select_alpn(const unsigned char **out, unsigned char *outlen,
+                        const unsigned char *in, unsigned int inlen) {
+  if (select_alpn(out, outlen, in, inlen, NGHTTP2_PROTO_ALPN,
+                  NGHTTP2_PROTO_ALPN_LEN) == 0) {
+    return 1;
+  }
+  if (select_alpn(out, outlen, in, inlen, NGHTTP2_HTTP_1_1_ALPN,
+                  NGHTTP2_HTTP_1_1_ALPN_LEN) == 0) {
+    return 0;
+  }
+  return -1;
+}