1 files changed, 65 insertions, 0 deletions
diff --git a/src/core/lib/transport/chttp2/varint.c b/src/core/lib/transport/chttp2/varint.c
new file mode 100644
index 0000000000..6dfef45362
--- /dev/null
+++ b/src/core/lib/transport/chttp2/varint.c
@@ -0,0 +1,65 @@
+/*
+ *
+ * Copyright 2015-2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include "src/core/lib/transport/chttp2/varint.h"
+
+uint32_t grpc_chttp2_hpack_varint_length(uint32_t tail_value) {
+  if (tail_value < (1 << 7)) {
+    return 2;
+  } else if (tail_value < (1 << 14)) {
+    return 3;
+  } else if (tail_value < (1 << 21)) {
+    return 4;
+  } else if (tail_value < (1 << 28)) {
+    return 5;
+  } else {
+    return 6;
+  }
+}
+
+void grpc_chttp2_hpack_write_varint_tail(uint32_t tail_value, uint8_t* target,
+                                         uint32_t tail_length) {
+  switch (tail_length) {
+    case 5:
+      target[4] = (uint8_t)((tail_value >> 28) | 0x80);
+    case 4:
+      target[3] = (uint8_t)((tail_value >> 21) | 0x80);
+    case 3:
+      target[2] = (uint8_t)((tail_value >> 14) | 0x80);
+    case 2:
+      target[1] = (uint8_t)((tail_value >> 7) | 0x80);
+    case 1:
+      target[0] = (uint8_t)((tail_value) | 0x80);
+  }
+  target[tail_length - 1] &= 0x7f;
+}