Mac Mania 6/MacMania 6.toast//Tools&Utilities/EnterAct Stuff/Drag_on Modules/hAWK programs/$Print_MPSR_1007

Text File | 1993-04-09 | 4KB | 163 lines

#$Print_MPSR_1007: print marker resource, as loaded by Read Resource.

#The approach below uses "input on demand" to allow us
#to step through the bytes in the resource. Each call to
#GetNextByte or PrintCharAndAdvance retrieves the next byte, grabbing
#the next input line if necessary. The variable bytePos is
#automatically advanced whenever a byte is read, and the calculation
#of the field number and position within the field is hidden within
#GetNextByte. To skip over n bytes, add n to bytePos.

#Format of mark resource:
#2        numMarks
#--repeated for numMarks:
#4        start
#4        end
#1        n = oddLen; rounded up to be odd
#n        mark text, padded sometimes with null

#Format of resource as retrieved by Read Resource:
#byteNumber: 4bytes 4bytes 4bytes 4bytes  ascii version of the bytes
#the last line may be padded with zeroes, for example
#      240: 07556E6D 61726BC9 00000000 09417574  .Unmark......Aut
#      256: 6F6D6172 6BC90000 00000000 00000000  omark......

#bytePos ranges 0 : up. It is automatically
#advanced when a byte is read by GetNextByte(). It can be
#manually advanced to skip unwanted bytes.

# User’s Manual references:
# «hAWK User’s Manual» «F   Running hAWK programs»
# «hAWK User’s Manual» «L  5   Regular expressions»
# «hAWK User’s Manual» «M  5   Built-in string and file functions»
# «hAWK User’s Manual» «K  4   Built-in variables»
# «hAWK User’s Manual» «K  8   Arrays»
# «hAWK User’s Manual» «N   User-defined functions»
# «hAWK User’s Manual» «P  3   The getline function»
# «hAWK User’s Manual» «O  3   Output into files»
# «hAWK User’s Manual» «Q   The hAWK function»

FNR == 1    {
            numMarks = GetNextBytesAsNumber(2)
            print "Total marks:", numMarks;
            while (1)
                {
                start = GetNextBytesAsNumber(4)
                end = GetNextBytesAsNumber(4)
                markLen = GetNextByte()
                printf("%6d %6d %4d %3d ", start, end, end-start, markLen);
                while (markLen > 0)
                    {
                    PrintCharAndAdvance();
                    --markLen;
                    }
                print ""
                }
            }



function PrintCharAndAdvance()
    {
    printf("%c", GetNextByte());
    }

#Convert ASCII representation of next byte, eg '1F', to a single
#number, eg 31.
function GetNextByte(        lineByte, field, char, pos)
    {
    #Convert byte position in resource to field and position in field.
    lineByte = bytePos - (FNR - 1) * 16;
    field = int((lineByte)/4);
    while (field > 3)#the next line of input is wanted
        {
        if ((getline) <= 0)
            {
            print ""; print "End of file."; exit;
            }
        lineByte = bytePos - (FNR - 1) * 16;
        field = int((lineByte)/4);
        }
    pos = lineByte - field * 4;
    field += 2;
    pos = 2 * pos + 1;
    char = HexToDec(substr($field, pos, 2));
    ++bytePos;
    return char
    }

#Return raw ASCII representation of byte, eg "2F".
function GetNextRawByte(        lineByte, field, char, pos)
    {
    #Convert byte position in resource to field and position in field.
    lineByte = bytePos - (FNR - 1) * 16;
    field = int((lineByte)/4);
    while (field > 3)#the next line of input is wanted
        {
        if ((getline) <= 0)
            {
            print ""; print "End of file."; exit;
            }
        lineByte = bytePos - (FNR - 1) * 16;
        field = int((lineByte)/4);
        }
    pos = lineByte - field * 4;
    field += 2;
    pos = 2 * pos + 1;
    ++bytePos;
    return substr($field, pos, 2);
    }

#Convert ASCII representation of 1, 2, or 4 bytes to a single
#unsigned number.
function GetNextBytesAsNumber(howManyBytes,        i, temp, numString, number)
    {
    for (i = 1; i <= howManyBytes; ++i)
        {
        temp = GetNextRawByte();
        numString = numString temp;
        }
    number = HexToDec(numString);
    return number;
    }

#General purpose ASCII hex to number conversion.
function HexToDec(h,     len, nyb, hexDigit, power, d)
    {
    d = 0;
    len = length(h);
    power = 1
    for (nyb = len; nyb >= 1; --nyb)
        {
        hexDigit = substr(h, nyb, 1);
        d += DecimalEquiv(hexDigit) * power;
        power *= 16;
        }
    return d
    }

#Convert one hex "digit" to the equivalent number.
function DecimalEquiv(hd, dd)
    {
    dd = 0;
    if (match(hd,/[0-9]/) > 0)
        dd = hd + 0;#conversion from string to number is implicit
    else if (match(hd, /[a-fA-F]/) > 0)
        {
        if (match(hd, /[aA]/) > 0)
            dd = 10;
        else if (match(hd, /[bB]/) > 0)
            dd = 11;
        else if (match(hd, /[cC]/) > 0)
            dd = 12;
        else if (match(hd, /[dD]/) > 0)
            dd = 13;
        else if (match(hd, /[eE]/) > 0)
            dd = 14;
        else if (match(hd, /[fF]/) > 0)
            dd = 15;
        }
    return dd
    }