System Booster/System Booster.iso/Screenblankers/ShadowMaster/rexx/build.rexx

OS/2 REXX Batch file | 1996-09-27 | 4.9 KB | 173 lines

/*
 * A hack to make building other programs easier, by extracting the
 * commands needed to build the file from it's source.
 *
 *    build [name NAME] [flags COMMAND=FLAGS ...] [file] FILE [FILE ...]
 *
 * Name defaults to "build". Flags causes the following arguments to be parsed
 * for extra flags to be added to each COMMAND. All input FILEs are scanned
 * for build lines to be issued to the system. If flags is present, file is
 * required.
 *
 * In scanning a file, build ignores all lines until it sees a line containing
 * the string "===NAME", for whatever value name has, defaulting to build. All
 * lines following are then processed until a line containing "===endNAME" is
 * encountered. Delimiter and control are set by parsing the line ===NAME line
 * as '===NAME delimiter DELIMITER control CONTROL'
 *
 * In processing the build lines, two tokens have special significance. They
 * are called delimiter and control, and are normally '%' and ';'. The line is
 * first split on the control character, into the front and back halves. If
 * there is a delimiter in the front half, any text preceding it is discarded.
 * If there is a delimiter in the back half, any text following it is discarded.
 *
 * The front half is treated as a command to be issued to the system. If the
 * first word of the front half is matched by a the command part of a flags
 * argument, then the flags part of that argument is inserted into the command
 * after the first word. I.e. the command issued is "command FLAGS rest of line".
 * The back half of the command is then checked, and the above comamnd is issued
 * if it is called for.
 *
 * The back half is assumed to be of the form 'output= FILE input= FILE ...'.
 * If any of the input files are newer than the output file, then the command
 * in the front half will be executed.  If either input or output keywords are
 * missing, the command is always issued.
 *
 * As a convenience, if the back half of a line is empty, then it will be
 * executed if the previous command was executed.
 *
 * Copyright 1991, Mike Meyer
 * All Rights Reserved
 *
 * See the file "Supersaver:Distribution" for information on distribution.
 */

/* Get the support code */
if ~show('Libraries', 'rexxsupport.library') then do
    if ~addlib('rexxsupport.library', 0, -30) then do
        say "Can't open rexxsupport.library!"
        exit
        end
    end

flags. = ''
flags = 0
name = 'build'
files = ''

/* Parse them arguments */
args = arg(1)
do i = 1 to words(args)
    select
        when upper(word(args, i)) = 'NAME' then do
            flags = 0
            i = i + 1
            name = word(args, i)
            end
        when upper(word(args, i)) = 'FILE' then do
            flags = 0
            i = i + 1
            files = word(args, i)
            end
        when upper(word(args, i)) = 'FLAGS' then flags = 1
        when flags then do
            parse value word(args, i) with command '=' flag
            if flag = '' then
                flags.currentcommand = flags.currentcommand word(args, i)
            else do
                currentcommand = command
                flags.command = flag
                end
            end
        otherwise files = files word(args, i)
        end
    end

/*
 * loop over the file names.
 */
files = expand(files)
do i = 1 to words(files)
    call buildfile(word(files, i), name)
    end

exit 0

/*
 * Scan a file, looking for the build instructions.
 */
buildfile: procedure expose flags.
    parse arg file, name

    delim = '%'
    control = ';'

    if ~open(input, file) then do
        say "Can't open file" file
        return 10
        end

    /* Search for the section with command in it */
    search = '==='upper(name)
    do until index(upper(line), search) ~= 0
        if eof(input) then do
            say "No actions found for" name "in file" file
            return 5
            end
        line = readln(input)
        end

    /* Check for control/delimter settings */
    parse var line 'control' new .
    if new ~= '' then control = new
    parse var line 'delimiter' new .
    if new ~= '' then delimiter = new

    /* Process the command lines */
    search = '===END'upper(name)
    line = readln(input)
    do while index(upper(line), search) = 0
        parse var line command (control) files

        /* Check files section */
        parse var files files (delim)
        parse var files "output=" outfile "input=" infiles
        if outfile = "" | infiles = "" then docommand = 1
        else do
            instamp = makestamp(strip(outfile))
            docommand = 0
            do i = 1 to words(infiles)
                if instamp < makestamp(word(infiles, i)) then do
                    docommand = 1
                    leave
                    end
                end
            end

        /* Build command to execute */
        parse var command (delim) new flags
        if new ~= "" then command = new
        else parse var command command flags
        if command ~= "" & docommand then do
            say command flags
            address command command flags.command flags
            if rc ~= 0 then exit rc
            end
        line = readln(input)

        if eof(input) then do
            say "No end to build section"
            exit 10
            end
        end

    call close input
    return 0

/* Get a files creation date as a numeric string */
makestamp: procedure
    arg filename

    parse value statef(filename) with . . . . d m t .
    return right(d, 4, 0) || right(m, 4, 0) || right(t, 4, 0)