Initial checkin of gRPC to third_party/

third_party/grpc/src/core/surface/byte_buffer_reader.c

Index: third_party/grpc/src/core/surface/byte_buffer_reader.c
diff --git a/third_party/grpc/src/core/surface/byte_buffer_reader.c b/third_party/grpc/src/core/surface/byte_buffer_reader.c
new file mode 100644
index 0000000000000000000000000000000000000000..4679854227377b7cc142d4a193ebe643ad57ee50
--- /dev/null
+++ b/third_party/grpc/src/core/surface/byte_buffer_reader.c
@@ -0,0 +1,123 @@
+/*
+ *
+ * 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.
+ *
+ */
+
+#include <string.h>
+#include <grpc/byte_buffer_reader.h>
+
+#include <grpc/compression.h>
+#include <grpc/grpc.h>
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+#include <grpc/support/slice_buffer.h>
+#include <grpc/byte_buffer.h>
+
+#include "src/core/compression/message_compress.h"
+
+static int is_compressed(grpc_byte_buffer *buffer) {
+  switch (buffer->type) {
+    case GRPC_BB_RAW:
+      if (buffer->data.raw.compression == GRPC_COMPRESS_NONE) {
+        return 0 /* GPR_FALSE */;
+      }
+      break;
+  }
+  return 1 /* GPR_TRUE */;
+}
+
+void grpc_byte_buffer_reader_init(grpc_byte_buffer_reader *reader,
+                                  grpc_byte_buffer *buffer) {
+  gpr_slice_buffer decompressed_slices_buffer;
+  reader->buffer_in = buffer;
+  switch (reader->buffer_in->type) {
+    case GRPC_BB_RAW:
+      gpr_slice_buffer_init(&decompressed_slices_buffer);
+      if (is_compressed(reader->buffer_in)) {
+        grpc_msg_decompress(reader->buffer_in->data.raw.compression,
+                            &reader->buffer_in->data.raw.slice_buffer,
+                            &decompressed_slices_buffer);
+        reader->buffer_out =
+            grpc_raw_byte_buffer_create(decompressed_slices_buffer.slices,
+                                        decompressed_slices_buffer.count);
+        gpr_slice_buffer_destroy(&decompressed_slices_buffer);
+      } else { /* not compressed, use the input buffer as output */
+        reader->buffer_out = reader->buffer_in;
+      }
+      reader->current.index = 0;
+      break;
+  }
+}
+
+void grpc_byte_buffer_reader_destroy(grpc_byte_buffer_reader *reader) {
+  switch (reader->buffer_in->type) {
+    case GRPC_BB_RAW:
+      /* keeping the same if-else structure as in the init function */
+      if (is_compressed(reader->buffer_in)) {
+        grpc_byte_buffer_destroy(reader->buffer_out);
+      }
+      break;
+  }
+}
+
+int grpc_byte_buffer_reader_next(grpc_byte_buffer_reader *reader,
+                                 gpr_slice *slice) {
+  switch (reader->buffer_in->type) {
+    case GRPC_BB_RAW: {
+      gpr_slice_buffer *slice_buffer;
+      slice_buffer = &reader->buffer_out->data.raw.slice_buffer;
+      if (reader->current.index < slice_buffer->count) {
+        *slice = gpr_slice_ref(slice_buffer->slices[reader->current.index]);
+        reader->current.index += 1;
+        return 1;
+      }
+      break;
+    }
+  }
+  return 0;
+}
+
+gpr_slice grpc_byte_buffer_reader_readall(grpc_byte_buffer_reader *reader) {
+  gpr_slice in_slice;
+  size_t bytes_read = 0;
+  const size_t input_size = grpc_byte_buffer_length(reader->buffer_out);
+  gpr_slice out_slice = gpr_slice_malloc(input_size);
+  uint8_t *const outbuf = GPR_SLICE_START_PTR(out_slice); /* just an alias */
+
+  while (grpc_byte_buffer_reader_next(reader, &in_slice) != 0) {
+    const size_t slice_length = GPR_SLICE_LENGTH(in_slice);
+    memcpy(&(outbuf[bytes_read]), GPR_SLICE_START_PTR(in_slice), slice_length);
+    bytes_read += slice_length;
+    gpr_slice_unref(in_slice);
+    GPR_ASSERT(bytes_read <= input_size);
+  }
+  return out_slice;
+}