Function tryReadSyncWithUserBuffer

lib/fs.js:485–513

(fd, isUserFd, buffer, byteLengthName)

}

function tryReadSyncWithUserBuffer(fd, isUserFd, buffer, byteLengthName) {
  let pos = 0;
  let bytesRead = 0;

  while (pos < buffer.byteLength) {
    bytesRead = tryReadSync(fd, isUserFd, buffer, pos, buffer.byteLength - pos);
    pos += bytesRead;

    if (bytesRead === 0) {
      return pos;
    }
  }

  const extraBuffer = tryCreateBuffer(1, fd, isUserFd);
  bytesRead = tryReadSync(fd, isUserFd, extraBuffer, 0, 1);

  if (bytesRead !== 0) {
    if (!isUserFd) {
      fs.closeSync(fd);
    }
    throw new ERR_INVALID_ARG_VALUE(
      byteLengthName,
      buffer.byteLength,
      'is too small to contain the entire file',
    );
  }

  return pos;
}

/**
 * Synchronously reads the entire contents of a file.