asn1_primitives_setters.h

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/*
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#ifndef ETSI_ITS_MSGS_UTILS_IMPL_ASN1_PRIMITIVES_ASN1_PRIMITIVES_SETTERS_H
#define ETSI_ITS_MSGS_UTILS_IMPL_ASN1_PRIMITIVES_ASN1_PRIMITIVES_SETTERS_H
 
template <typename T>
inline void setBitString(T& bitstring, const std::vector<bool>& bits) {
  // bit string size
  const int bits_per_byte = 8;
  const int n_bytes = (bits.size() - 1) / bits_per_byte + 1;
  const int n_bits = n_bytes * bits_per_byte;
 
  // init output
  bitstring.bits_unused = n_bits - bits.size();
  bitstring.value = std::vector<uint8_t>(n_bytes);
 
  // loop over all bytes in reverse order
  for (int byte_idx = n_bytes - 1; byte_idx >= 0; byte_idx--) {
 
    // loop over bits in a byte
    for (int bit_idx_in_byte = bits_per_byte - 1; bit_idx_in_byte >= 0; bit_idx_in_byte--) {
 
      // map bit index in byte to bit index in total bitstring
      int bit_idx = (n_bytes - byte_idx - 1) * bits_per_byte + bit_idx_in_byte;
      if (byte_idx == 0 && bit_idx < bitstring.bits_unused) break;
 
      // set bit in output bitstring appropriately
      if (bit_idx < bits.size()) {
        bitstring.value[byte_idx] |= bits[bits_per_byte - bit_idx - 1] << bit_idx_in_byte;
      }
    }
  }
}
 
#endif // ETSI_ITS_MSGS_UTILS_IMPL_ASN1_PRIMITIVES_SETTERS_H