Fix OBU total length error

src/rtp/byte_buffer.cpp

@@ -0,0 +1,62 @@
+#include "byte_buffer.h"
+
+#include <string.h>
+
+ByteBufferReader::ByteBufferReader(const char* bytes, size_t len) {
+  Construct(bytes, len);
+}
+
+void ByteBufferReader::Construct(const char* bytes, size_t len) {
+  bytes_ = bytes;
+  size_ = len;
+  start_ = 0;
+  end_ = len;
+}
+
+bool ByteBufferReader::ReadBytes(char* val, size_t len) {
+  if (len > Length()) {
+    return false;
+  } else {
+    memcpy(val, bytes_ + start_, len);
+    start_ += len;
+    return true;
+  }
+}
+
+bool ByteBufferReader::ReadUInt8(uint8_t* val) {
+  if (!val) return false;
+
+  return ReadBytes(reinterpret_cast<char*>(val), 1);
+}
+
+bool ByteBufferReader::ReadUVarint(uint64_t* val, size_t* len) {
+  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) {
+    char 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;
+    // True if the msb is not a continuation byte.
+    if (static_cast<uint64_t>(byte) < 0x80) {
+      *val = v;
+      if (len) {
+        *len = i / 8 + (i % 8 ? 1 : 0) + 1;
+      }
+      return true;
+    }
+  }
+  return false;
+}
+
+bool ByteBufferReader::Consume(size_t size) {
+  if (size > Length()) return false;
+  start_ += size;
+  return true;
+}