C++ (Cpp) getReadPosition Examples

Example #1

File: plain-file.cpp Project: AeroEng43/hhvm

bool PlainFile::seek(int64_t offset, int whence /* = SEEK_SET */) {
  assert(valid());

  if (whence == SEEK_CUR) {
    off_t result = lseek(getFd(), 0, SEEK_CUR);
    if (result != (off_t)-1) {
      offset += result - (bufferedLen() + getPosition());
    }
    if (offset > 0 && offset < bufferedLen()) {
      setReadPosition(getReadPosition() + offset);
      setPosition(getPosition() + offset);
      return true;
    }
    offset += getPosition();
    whence = SEEK_SET;
  }

  // invalidate the current buffer
  setWritePosition(0);
  setReadPosition(0);
  // clear the eof flag
  setEof(false);
  flush();
  // lseek instead of seek to be consistent with read
  off_t result = lseek(getFd(), offset, whence);
  setPosition(result);
  return result != (off_t)-1;
}

Example #2

File: zip-file.cpp Project: josephcopenhaver/hhvm

bool ZipFile::seek(int64_t offset, int whence /* = SEEK_SET */) {
  assert(m_gzFile);

  if (whence == SEEK_CUR) {
    off_t result = gzseek(m_gzFile, 0, SEEK_CUR);
    if (result != (off_t)-1) {
      offset += result - (bufferedLen() + getPosition());
    }
    if (offset > 0 && offset < bufferedLen()) {
      setReadPosition(getReadPosition() + offset);
      setPosition(getPosition() + offset);
      return true;
    }
    offset += getPosition();
    whence = SEEK_SET;
  }

  // invalidate the current buffer
  setWritePosition(0);
  setReadPosition(0);
  setEof(false);
  flush();
  off_t result = gzseek(m_gzFile, offset, whence);
  setPosition(result);
  return result != (off_t)-1;
}

Example #3

File: user-file.cpp Project: HilayPatel/hhvm

bool UserFile::seek(int64_t offset, int whence /* = SEEK_SET */) {
  assert(seekable());

  // Seek within m_buffer if we can, otherwise kill it and call user stream_seek / stream_tell
  if (whence == SEEK_CUR &&
      0 <= getReadPosition() + offset &&
           getReadPosition() + offset < getWritePosition()) {
    setReadPosition(getReadPosition() + offset);
    setPosition(getPosition() + offset);
    return true;
  } else if (whence == SEEK_SET &&
             0 <= offset - getPosition() + getReadPosition() &&
             offset - getPosition() + getReadPosition() < getWritePosition()) {
    setReadPosition(offset - getPosition() + getReadPosition());
    setPosition(offset);
    return true;
  } else {
    if (whence == SEEK_CUR) {
      offset += getReadPosition() - getWritePosition();
    }
    setReadPosition(0);
    setWritePosition(0);
  }

  // bool stream_seek($offset, $whence)
  bool invoked = false;
  bool sought  = invoke(
    m_StreamSeek, s_stream_seek, make_packed_array(offset, whence), invoked
  ).toBoolean();
  if (!invoked) {
    always_assert("No seek method? But I found one earlier?");
  }
  if (!sought) {
    return false;
  }

  // int stream_tell()
  Variant ret = invoke(m_StreamTell, s_stream_tell, Array::Create(), invoked);
  if (!invoked) {
    raise_warning("%s::stream_tell is not implemented!", m_cls->name()->data());
    return false;
  }
  setPosition(ret.isInteger() ? ret.toInt64() : -1);
  return true;
}

Example #4

File: mem-file.cpp Project: fredemmott/hhvm

bool MemFile::seek(int64_t offset, int whence /* = SEEK_SET */) {
  assertx(m_len != -1);
  if (whence == SEEK_CUR) {
    if (offset > 0 && offset < bufferedLen()) {
      setReadPosition(getReadPosition() + offset);
      setPosition(getPosition() + offset);
      return true;
    }
    offset += getPosition();
    whence = SEEK_SET;
  }

  // invalidate the current buffer
  setWritePosition(0);
  setReadPosition(0);
  if (whence == SEEK_SET) {
    m_cursor = offset;
  } else {
    assertx(whence == SEEK_END);
    m_cursor = m_len + offset;
  }
  setPosition(m_cursor);
  return true;
}