Function StrToIpv4Address

MdePkg/Library/BaseLib/SafeString.c:1367–1468

Convert a Null-terminated Unicode string to IPv4 address and prefix length. This function outputs a value of type IPv4_ADDRESS and may output a value of type UINT8 by interpreting the contents of the Unicode string specified by String. The format of the input Unicode string String is as follows: D.D.D.D[/P] D and P are decimal digit characters in the range [0-9

**/
RETURN_STATUS
EFIAPI
StrToIpv4Address (
  IN  CONST CHAR16       *String,
  OUT CHAR16             **EndPointer, OPTIONAL
  OUT IPv4_ADDRESS       *Address,
  OUT UINT8              *PrefixLength OPTIONAL
  )
{
  RETURN_STATUS          Status;
  UINTN                  AddressIndex;
  UINTN                  Uintn;
  IPv4_ADDRESS           LocalAddress;
  UINT8                  LocalPrefixLength;
  CHAR16                 *Pointer;

  LocalPrefixLength = MAX_UINT8;

  ASSERT (((UINTN) String & BIT0) == 0);

  //
  // 1. None of String or Guid shall be a null pointer.
  //
  SAFE_STRING_CONSTRAINT_CHECK ((String != NULL), RETURN_INVALID_PARAMETER);
  SAFE_STRING_CONSTRAINT_CHECK ((Address != NULL), RETURN_INVALID_PARAMETER);

  for (Pointer = (CHAR16 *) String, AddressIndex = 0; AddressIndex < ARRAY_SIZE (Address->Addr) + 1;) {
    if (!InternalIsDecimalDigitCharacter (*Pointer)) {
      //
      // D or P contains invalid characters.
      //
      break;
    }

    //
    // Get D or P.
    //
    Status = StrDecimalToUintnS ((CONST CHAR16 *) Pointer, &Pointer, &Uintn);
    if (RETURN_ERROR (Status)) {
      return RETURN_UNSUPPORTED;
    }
    if (AddressIndex == ARRAY_SIZE (Address->Addr)) {
      //
      // It's P.
      //
      if (Uintn > 32) {
        return RETURN_UNSUPPORTED;
      }
      LocalPrefixLength = (UINT8) Uintn;
    } else {
      //
      // It's D.
      //
      if (Uintn > MAX_UINT8) {
        return RETURN_UNSUPPORTED;
      }
      LocalAddress.Addr[AddressIndex] = (UINT8) Uintn;
      AddressIndex++;