Initial checkin of gRPC to third_party/

third_party/grpc/src/core/transport/chttp2/hpack_encoder.h

Index: third_party/grpc/src/core/transport/chttp2/hpack_encoder.h
diff --git a/third_party/grpc/src/core/transport/chttp2/hpack_encoder.h b/third_party/grpc/src/core/transport/chttp2/hpack_encoder.h
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index 0000000000000000000000000000000000000000..19b5cb72ae1579dd8a27086ec3e49b7ee1397623
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+++ b/third_party/grpc/src/core/transport/chttp2/hpack_encoder.h
@@ -0,0 +1,95 @@
+/*
+ *
+ * Copyright 2015, 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.
+ *
+ */
+
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_HPACK_ENCODER_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_HPACK_ENCODER_H
+
+#include "src/core/transport/chttp2/frame.h"
+#include "src/core/transport/metadata.h"
+#include "src/core/transport/metadata_batch.h"
+#include <grpc/support/port_platform.h>
+#include <grpc/support/slice.h>
+#include <grpc/support/slice_buffer.h>
+
+#define GRPC_CHTTP2_HPACKC_NUM_FILTERS 256
+#define GRPC_CHTTP2_HPACKC_NUM_VALUES 256
+/* initial table size, per spec */
+#define GRPC_CHTTP2_HPACKC_INITIAL_TABLE_SIZE 4096
+/* maximum table size we'll actually use */
+#define GRPC_CHTTP2_HPACKC_MAX_TABLE_SIZE (1024 * 1024)
+
+typedef struct {
+  uint32_t filter_elems_sum;
+  uint32_t max_table_size;
+  uint32_t max_table_elems;
+  uint32_t cap_table_elems;
+  /** if non-zero, advertise to the decoder that we'll start using a table
+      of this size */
+  uint8_t advertise_table_size_change;
+  /** maximum number of bytes we'll use for the decode table (to guard against
+      peers ooming us by setting decode table size high) */
+  uint32_t max_usable_size;
+  /* one before the lowest usable table index */
+  uint32_t tail_remote_index;
+  uint32_t table_size;
+  uint32_t table_elems;
+
+  /* filter tables for elems: this tables provides an approximate
+     popularity count for particular hashes, and are used to determine whether
+     a new literal should be added to the compression table or not.
+     They track a single integer that counts how often a particular value has
+     been seen. When that count reaches max (255), all values are halved. */
+  uint8_t filter_elems[GRPC_CHTTP2_HPACKC_NUM_FILTERS];
+
+  /* entry tables for keys & elems: these tables track values that have been
+     seen and *may* be in the decompressor table */
+  grpc_mdstr *entries_keys[GRPC_CHTTP2_HPACKC_NUM_VALUES];
+  grpc_mdelem *entries_elems[GRPC_CHTTP2_HPACKC_NUM_VALUES];
+  uint32_t indices_keys[GRPC_CHTTP2_HPACKC_NUM_VALUES];
+  uint32_t indices_elems[GRPC_CHTTP2_HPACKC_NUM_VALUES];
+
+  uint16_t *table_elem_size;
+} grpc_chttp2_hpack_compressor;
+
+void grpc_chttp2_hpack_compressor_init(grpc_chttp2_hpack_compressor *c);
+void grpc_chttp2_hpack_compressor_destroy(grpc_chttp2_hpack_compressor *c);
+void grpc_chttp2_hpack_compressor_set_max_table_size(
+    grpc_chttp2_hpack_compressor *c, uint32_t max_table_size);
+void grpc_chttp2_hpack_compressor_set_max_usable_size(
+    grpc_chttp2_hpack_compressor *c, uint32_t max_table_size);
+
+void grpc_chttp2_encode_header(grpc_chttp2_hpack_compressor *c, uint32_t id,
+                               grpc_metadata_batch *metadata, int is_eof,
+                               gpr_slice_buffer *outbuf);
+
+#endif /* GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_HPACK_ENCODER_H */