Function AsciiStriCmp

MdePkg/Library/BaseLib/String.c:1389–1424

Performs a case insensitive comparison of two Null-terminated ASCII strings, and returns the difference between the first mismatched ASCII characters. This function performs a case insensitive comparison of the Null-terminated ASCII string FirstString to the Null-terminated ASCII string SecondString. If FirstString is identical to SecondString, then 0 is returned. Otherwise, the v

**/
INTN
EFIAPI
AsciiStriCmp (
  IN      CONST CHAR8               *FirstString,
  IN      CONST CHAR8               *SecondString
  )
{
  CHAR8  UpperFirstString;
  CHAR8  UpperSecondString;

  //
  // ASSERT both strings are less long than PcdMaximumAsciiStringLength
  //
 // ASSERT (AsciiStrSize (FirstString));
 // ASSERT (AsciiStrSize (SecondString));
  if (!AsciiStrSize (FirstString) && !AsciiStrSize (SecondString)) {
    return 0;
  }
  if (!AsciiStrSize (FirstString)) {
    return -1;
  }
  if (!AsciiStrSize (SecondString)) {
    return 1;
  }

  UpperFirstString  = AsciiCharToUpper (*FirstString);
  UpperSecondString = AsciiCharToUpper (*SecondString);
  while ((*FirstString != '\0') && (*SecondString != '\0') && (UpperFirstString == UpperSecondString)) {
    FirstString++;
    SecondString++;
    UpperFirstString  = AsciiCharToUpper (*FirstString);
    UpperSecondString = AsciiCharToUpper (*SecondString);
  }

  return UpperFirstString - UpperSecondString;
}

/**
  Compares two Null-terminated ASCII strings with maximum lengths, and returns