1 files changed, 99 insertions, 0 deletions
diff --git a/src/core/transport/chttp2/frame_window_update.c b/src/core/transport/chttp2/frame_window_update.c
new file mode 100644
index 0000000000..f61714f52b
--- /dev/null
+++ b/src/core/transport/chttp2/frame_window_update.c
@@ -0,0 +1,99 @@
+/*
+ *
+ * Copyright 2014, 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/transport/chttp2/frame_window_update.h"
+
+#include <grpc/support/log.h>
+
+gpr_slice grpc_chttp2_window_update_create(gpr_uint32 id,
+                                           gpr_uint32 window_update) {
+  gpr_slice slice = gpr_slice_malloc(13);
+  gpr_uint8 *p = GPR_SLICE_START_PTR(slice);
+
+  GPR_ASSERT(window_update);
+
+  *p++ = 0;
+  *p++ = 0;
+  *p++ = 4;
+  *p++ = GRPC_CHTTP2_FRAME_WINDOW_UPDATE;
+  *p++ = 0;
+  *p++ = id >> 24;
+  *p++ = id >> 16;
+  *p++ = id >> 8;
+  *p++ = id;
+  *p++ = window_update >> 24;
+  *p++ = window_update >> 16;
+  *p++ = window_update >> 8;
+  *p++ = window_update;
+
+  return slice;
+}
+
+grpc_chttp2_parse_error grpc_chttp2_window_update_parser_begin_frame(
+    grpc_chttp2_window_update_parser *parser, gpr_uint32 length,
+    gpr_uint8 flags) {
+  if (flags || length != 4) {
+    gpr_log(GPR_ERROR, "invalid window update: length=%d, flags=%02x", length,
+            flags);
+    return GRPC_CHTTP2_CONNECTION_ERROR;
+  }
+  parser->byte = 0;
+  parser->amount = 0;
+  return GRPC_CHTTP2_PARSE_OK;
+}
+
+grpc_chttp2_parse_error grpc_chttp2_window_update_parser_parse(
+    void *parser, grpc_chttp2_parse_state *state, gpr_slice slice,
+    int is_last) {
+  gpr_uint8 *const beg = GPR_SLICE_START_PTR(slice);
+  gpr_uint8 *const end = GPR_SLICE_END_PTR(slice);
+  gpr_uint8 *cur = beg;
+  grpc_chttp2_window_update_parser *p = parser;
+
+  while (p->byte != 4 && cur != end) {
+    p->amount |= ((gpr_uint32)*cur) << (8 * (3 - p->byte));
+    cur++;
+    p->byte++;
+  }
+
+  if (p->byte == 4) {
+    if (p->amount == 0 || (p->amount & 0x80000000u)) {
+      gpr_log(GPR_ERROR, "invalid window update bytes: %d", p->amount);
+      return GRPC_CHTTP2_CONNECTION_ERROR;
+    }
+    GPR_ASSERT(is_last);
+    state->window_update = p->amount;
+  }
+
+  return GRPC_CHTTP2_PARSE_OK;
+}