Repo created

TMessagesProj/jni/voip/webrtc/rtc_base/byte_buffer.cc

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+/*
+ *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "rtc_base/byte_buffer.h"
+
+#include <string.h>
+
+namespace rtc {
+
+ByteBufferWriter::ByteBufferWriter() : ByteBufferWriterT() {}
+
+ByteBufferWriter::ByteBufferWriter(const uint8_t* bytes, size_t len)
+    : ByteBufferWriterT(bytes, len) {}
+
+ByteBufferReader::ByteBufferReader(rtc::ArrayView<const uint8_t> bytes) {
+  Construct(bytes.data(), bytes.size());
+}
+
+ByteBufferReader::ByteBufferReader(const ByteBufferWriter& buf) {
+  Construct(reinterpret_cast<const uint8_t*>(buf.Data()), buf.Length());
+}
+
+void ByteBufferReader::Construct(const uint8_t* bytes, size_t len) {
+  bytes_ = bytes;
+  size_ = len;
+  start_ = 0;
+  end_ = len;
+}
+
+bool ByteBufferReader::ReadUInt8(uint8_t* val) {
+  if (!val)
+    return false;
+
+  return ReadBytes(val, 1);
+}
+
+bool ByteBufferReader::ReadUInt16(uint16_t* val) {
+  if (!val)
+    return false;
+
+  uint16_t v;
+  if (!ReadBytes(reinterpret_cast<uint8_t*>(&v), 2)) {
+    return false;
+  } else {
+    *val = NetworkToHost16(v);
+    return true;
+  }
+}
+
+bool ByteBufferReader::ReadUInt24(uint32_t* val) {
+  if (!val)
+    return false;
+
+  uint32_t v = 0;
+  uint8_t* read_into = reinterpret_cast<uint8_t*>(&v);
+  ++read_into;
+
+  if (!ReadBytes(read_into, 3)) {
+    return false;
+  } else {
+    *val = NetworkToHost32(v);
+    return true;
+  }
+}
+
+bool ByteBufferReader::ReadUInt32(uint32_t* val) {
+  if (!val)
+    return false;
+
+  uint32_t v;
+  if (!ReadBytes(reinterpret_cast<uint8_t*>(&v), 4)) {
+    return false;
+  } else {
+    *val = NetworkToHost32(v);
+    return true;
+  }
+}
+
+bool ByteBufferReader::ReadUInt64(uint64_t* val) {
+  if (!val)
+    return false;
+
+  uint64_t v;
+  if (!ReadBytes(reinterpret_cast<uint8_t*>(&v), 8)) {
+    return false;
+  } else {
+    *val = NetworkToHost64(v);
+    return true;
+  }
+}
+
+bool ByteBufferReader::ReadUVarint(uint64_t* val) {
+  if (!val) {
+    return false;
+  }
+  // Integers are deserialized 7 bits at a time, with each byte having a
+  // continuation byte (msb=1) if there are more bytes to be read.
+  uint64_t v = 0;
+  for (int i = 0; i < 64; i += 7) {
+    uint8_t byte;
+    if (!ReadBytes(&byte, 1)) {
+      return false;
+    }
+    // Read the first 7 bits of the byte, then offset by bits read so far.
+    v |= (static_cast<uint64_t>(byte) & 0x7F) << i;
+    // Return if the msb is not a continuation byte.
+    if (byte < 0x80) {
+      *val = v;
+      return true;
+    }
+  }
+  return false;
+}
+
+bool ByteBufferReader::ReadString(std::string* val, size_t len) {
+  if (!val)
+    return false;
+
+  if (len > Length()) {
+    return false;
+  } else {
+    val->append(reinterpret_cast<const char*>(bytes_ + start_), len);
+    start_ += len;
+    return true;
+  }
+}
+
+bool ByteBufferReader::ReadStringView(absl::string_view* val, size_t len) {
+  if (!val || len > Length())
+    return false;
+  *val = absl::string_view(reinterpret_cast<const char*>(bytes_ + start_), len);
+  start_ += len;
+  return true;
+}
+
+bool ByteBufferReader::ReadBytes(rtc::ArrayView<uint8_t> val) {
+  if (val.size() == 0) {
+    return true;
+  }
+  return ReadBytes(val.data(), val.size());
+}
+
+// Private function supporting the other Read* functions.
+bool ByteBufferReader::ReadBytes(uint8_t* val, size_t len) {
+  if (len > Length()) {
+    return false;
+  }
+  if (len == 0) {
+    return true;
+  }
+  memcpy(val, bytes_ + start_, len);
+  start_ += len;
+  return true;
+}
+
+bool ByteBufferReader::Consume(size_t size) {
+  if (size > Length())
+    return false;
+  start_ += size;
+  return true;
+}
+
+}  // namespace rtc