! mathpars.h - Parse Big Numbers and other formats in Inform. ! Version 1.0 (19-Sep-2001) ! ! by Matt Albrecht - groboclown@users.sourceforge.net ! ! (If you need to edit this file, note that indentations are 4 spaces ! and tabs are not used.) ! ! This has been donated to the Public Domain. Use, abuse, and don't blame me. ! ! To prevent dirtying the global namespace, all members of this file begin with ! "mathpars_", while members private to this file begin with "mathpars__". ! Due to unsigned stuff, requires Z-Machine version 5 or older. System_file; ! C-like header! Ifndef MATHPARS__INCLUDED; Constant MATHPARS__INCLUDED; Message "Adding Big Number Parser library"; !------------------------------------------------------------------------------- ! Signed Math routines !------------------------------------------------------------------------------- !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! ! Used for scoping in the grammar, such as: !Verb 'type' ! * mathpars_BigNumber 'on'/'onto'/'in'/'with' Keypad -> Type reverse ! * 'on'/'onto'/'in'/'with' Keypad mathpars_BigNumber -> Type; [ mathpars_BigNumber val text old_cf len old_cw old_wn; ! locals old_wn = wn; if (NextWordStopped() == -1) { ! no more words return GPR_FAIL; } wn = old_wn; text = WordAddress( wn ); len = WordLength( wn ); !print "[ length of word ",wn," is ",len," ]^"; if (len >= 0) { if (text->0 >= '0' && text->0 <= '9') { val = -1; old_cf = consult_from; old_cw = consult_words; consult_words = 1; consult_from = wn; switch (text->(len-1)) { 'b' : !print "[ parsing big number: binary ]^"; val = mathpars_readBinValue(); 'h' : !print "[ parsing big number: hex ]^"; val = mathpars_readHexValue(); '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'd': !print "[ parsing big number: decimal ]^"; val = mathpars_readDecValue(); } consult_from = old_cf; consult_words = old_cw; if (val ~= -1) { ++wn; parsed_number = val; !print "[ returning number ",val," ]^"; return GPR_NUMBER; } } } !print "[ did not find a number ]^"; return GPR_FAIL; ]; !----------------------------------------------------------------- ! Reads in from the input parse buffer a hex value, and returns ! it as a number. If the global Mathpars_Result is non-zero, then ! the value is not a Hex value. The value read is considered ! the consult part of the buffer. !----------------------------------------------------------------- Global Mathpars_Result; [ mathpars_readHexValue val digit text i pos len start; Mathpars_Result = 0; if (consult_words ~= 1) { HexResult = -1; return -1; } pos = consult_from; !print "[readHexValue "; text = WordAddress( pos ); !print "(hex = ",(string)text,")"; len = WordLength( pos ); if (len >= 1) { if (text->(len-1) == 'h') { ! allow for the last character in the string to be a ! 'h', for 80x86 assembly compatability mode. --len; } } while (text->start == '0') { ++start; } if ((len-start) > 4) { ! we can only process up to 4 hex digits Mathpars_Result = -2; return -1; } val = 0; for (i = start : i < len : i++) { !print ": digit ",(char)text->i," is decimal "; if (text->i >= '0' && text->i <= '9') { digit = text->i - '0'; } else if (text->i >= 'a' && text->i <= 'f') { digit = text->i - 'a' + 10; } else if (text->i >= 'A' && text->i <= 'F') { digit = text->i - 'A' + 10; } else { ! non-hex value !print "*not hex value*^"; Mathpars_Result = text->i; return -1; } ! add in the new digit val = val * 16 + digit; !print digit," (val now ",val,")"; } !print ": returning value ",val,"]^"; return val; ]; !----------------------------------------------------------------- ! Reads in from input parse buffer a binary value, and returns it ! as a number. If the global Mathpars_HexResult non-zero, then ! the value is not a Binary value. The value read is considered ! the consult part of the buffer. !----------------------------------------------------------------- [ mathpars_readBinValue val digit text i pos len start; ! locals Mathpars_Result = 0; if (consult_words ~= 1) { Mathpars_Result = -1; return -1; } pos = consult_from; !print "[readBinValue "; text = WordAddress( pos ); !print "(bin = ",(string)text,")"; len = WordLength( pos ); if (len >= 1) { if (text->(len-1) == 'b') { ! allow for the last character in the string to be a ! 'b', for 80x86 assembly compatability mode. --len; } } while (text->start == '0') { ++start; } if ((len-start) > 8) { ! we can only process up to 8 binary digits Mathpars_Result = -2; return -1; } val = 0; for (i = 0 : i < len : i++) { !print ": digit ",(char)text->i," is decimal "; if (text->i >= '0' && text->i <= '1') { digit = text->i - '0'; } else { ! non-bin value !print "*not binary value*^"; Mathpars_Result = text->i; return -1; } ! add in the new digit val = val * 2 + digit; !print digit," (val now ",val,")"; } !print ": returning value ",val,"]^"; return val; ]; !----------------------------------------------------------------- ! Reads in from input parse buffer a binary value, and returns it ! as a number. If the global HexResult non-zero, then ! the value is not a Hex value. The value read is considered ! the consult part of the buffer. !----------------------------------------------------------------- [ mathpars_readDecValue val digit text i pos len; ! locals Mathpars_Result = 0; if (consult_words ~= 1) { Mathpars_Result = -1; return -1; } pos = consult_from; !print "[readDecValue "; text = WordAddress( pos ); !print "(dec = ",(string)text,")"; len = WordLength( pos ); if (len >= 1) { if (text->(len-1) == 'd') { ! allow for the last character in the string to be a ! 'd', for 80x86 assembly compatability mode. --len; } } for (i = 0 : i < len : i++) { !print ": digit ",(char)text->i," is decimal "; if (text->i >= '0' && text->i <= '9') { digit = text->i - '0'; } else { ! non-decimal value !print "*not decimal value*^"; Mathpars_Result = text->i; return -1; } ! add in the new digit val = val * 10 + digit; !print digit," (val now ",val,")"; } !print ": returning value ",val,"]^"; return val; ]; Endif; ! MATHPARS_INCLUDED