source: main/trunk/greenstone2/perllib/convertutil.pm@ 38698

###########################################################################
#
# convertutil.pm -- utility to help convert files using external applications
#
# Copyright (C) 1999 DigiLib Systems Limited, NZ
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
#
###########################################################################


package convertutil;

use strict;
no strict 'refs'; # allow filehandles to be variables and viceversa


use File::Basename;


sub monitor_init
{
    # do nothing
    return {};
}

sub monitor_deinit
{
    my ($saved_rec) = @_;
    
    # nothing to do
}

sub monitor_init_unbuffered
{
    my $saved_buffer_len = $|;
    $| = 1;

    my $saved_rec = { 'saved_buffer_len' => $saved_buffer_len };

    return $saved_rec;
}

sub monitor_deinit_unbuffered
{
    my ($saved_rec) = @_;

    my $saved_buffer_len = $saved_rec->{'saved_buffer_len'};

    $| = $saved_buffer_len;
}

sub monitor_line
{
    my ($line) = @_;

    my $had_error = 0;
    my $generate_dot = 0;

    return ($had_error,$generate_dot);
}

sub monitor_line_with_dot
{
    my ($line) = @_;

    my $had_error = 0;
    my $generate_dot = 1;

    return ($had_error,$generate_dot);
}


sub run_general_cmd
{
    my ($command,$options) = @_;

    # $options points to a hashtable that must have fields for:
    #  'verbosity', 'outhandle', 'message_prefix' and 'message'
    #
    # it can also include functions for monitoring
    #  'monitor_init'   => takes no input arguments and returns a hashtable for saved data values
    #  'monitor_line'   => takes $line as input argument, return tuple (had_error,generate_dot)
    #  'monitor_deinit' => takes the saved data values as input, restores saved values
    #
    # Default are provided for these monitor functions if none specified


    my $verbosity = $options->{'verbosity'};
    my $outhandle = $options->{'outhandle'};

    my $message_prefix = $options->{'message_prefix'};
    my $message = $options->{'message'};
    
    my $monitor_init   = $options->{'monitor_init'};
    my $monitor_line   = $options->{'monitor_line'};
    my $monitor_deinit = $options->{'monitor_deinit'};

    if (!defined $monitor_init) {
    $monitor_init = "monitor_init";
    }
    if (!defined $monitor_line) {
    $monitor_line = "monitor_line";
    }
    if (!defined $monitor_deinit) {
    $monitor_deinit = "monitor_deinit";
    }

#   my ($cpackage,$cfilename,$cline,$csubr,$chas_args,$cwantarray) = caller(4);
#   print STDERR "Calling method: $cfilename:$cline $cpackage->$csubr:$cline\n";

    print $outhandle "$message_prefix: $command\n" if ($verbosity > 3);
    print $outhandle "  $message ..." if ($verbosity >= 1);

    my $command_status = undef;
    my $result = "";
    my $had_error = 0;

    my $saved_rec = &$monitor_init();

    if (open(CMD,"$command 2>&1 |"))
    {
    my $line;

    my $linecount = 0;
    my $dot_count = 0;


    while (defined ($line = <CMD>))
    {
        $linecount++;

        my ($had_local_error,$generate_dot) = &$monitor_line($line);
        
        if ($had_local_error) {
        # set general flag, but allow loop to continue to end building up the $result line
        print $outhandle "$line\n";
        $had_error = 1;
        }

    
        if ($generate_dot)
        {
            if ($dot_count == 0) { print $outhandle "\n  "; }
            print $outhandle ".";
            $dot_count++;
                if (($dot_count%76)==0) 
            {
                print $outhandle "\n  ";
            }
        }
        
        $result .= $line;
        
    }
    print $outhandle "\n";

    
    close(CMD);

    $command_status = $?;
    if ($command_status != 0) {
        $had_error = 1;
        
        # for commands that go via an intermediate layer (like commands to imagemagick go 
        # through gs-magick.pl), need to shift exit code by 8 and then convert to its 
        # signed value to get the actual exit code that imagemagick had emitted.
        $command_status >>= 8;
        $command_status = (($command_status & 0x80) ? -(0x100 - ($command_status & 0xFF)) : $command_status);   

        print $outhandle "Error: processing command failed.  Exit status $command_status\n";

        if ($verbosity >= 3) {
        print $outhandle "  Command was: $command\n";
        }
        if ($verbosity >= 4) {
        print $outhandle "$message_prefix result: $result\n";
        }
    }
    }
    else 
    {
    $had_error = 1;
    print STDERR "Error: failed to execute $command\n";
    }

    &$monitor_deinit($saved_rec);

    if ($verbosity >= 1) {
    if ($had_error) {
        print $outhandle "  ...error encountered\n";
    }
    else {
        print $outhandle "  ...done\n";
    }
    }

    if (defined $command_status && ($command_status == 0))
    {
    # only want to print the following out if verbosity is high enough
    # and we haven't already printed it out as a detected error above
    print $outhandle "$message_prefix result: $result\n" if ($verbosity > 5);
    }

    return ($result,$had_error);
}


sub regenerate_general_cmd
{
    my ($command,$ifilename,$ofilename,$options) = @_;

    my $regenerated = 1;
    my $result = "";
    my $had_error = 0;

    ($result,$had_error) = run_general_cmd($command,$options);

    # store command args so can be compared with subsequent runs of the command
    my $args_filename = "$ofilename.args";

    if (open(ARGSOUT,">$args_filename")) {
    # for portability between Greenstone installation, substitute gsdl environment variable in $command
    my $gsdl3srchome = $ENV{'GSDL3SRCHOME'};
    my $gsdl_substitute_command = $command;
    $gsdl_substitute_command =~ s@$gsdl3srchome@\$GSDL3SRCHOME@g;
    
    print ARGSOUT $gsdl_substitute_command;
    print ARGSOUT "\n";
    close(ARGSOUT);
    }
    else {
    my $outhandle = $options->{'outhandle'};
    print $outhandle "Warning: Unable to write out caching information to file $args_filename\n";
    print $outhandle "         This means $ofilename will be regenerated on next build whether\n";
    print $outhandle "         processing args have changed or not.\n";
    }

    # Store the result, since ImageConverter.pm extracts the image height and width from the processed result
    my $result_filename = "$ofilename.result";
    if (open(RESOUT, ">$result_filename"))
    {
    print RESOUT $result;
    close(RESOUT);
    }
    else
    {
    my $outhandle = $options->{'outhandle'};
    print $outhandle "Warning: Unable to write out cached process result to file $result_filename.\n";
    }

    return ($regenerated,$result,$had_error);
}



sub run_cached_general_cmd
{
    my ($command,$ifilename,$ofilename,$options) = @_;

    my $outhandle = $options->{'outhandle'};
    my $verbosity = $options->{'verbosity'};
    my $message_prefix = $options->{'message_prefix'};

    my $regenerated = 0;
    my $result = "";
    my $had_error = 0;

    my $args_filename = "$ofilename.args";

    if ((!-e $ofilename) || (!-e $args_filename)) {
    ($regenerated,$result,$had_error) 
        = regenerate_general_cmd($command,$ifilename,$ofilename,$options);
    }
    elsif (-M $ifilename < -M $args_filename) {
    # Source files has been updated/changed in some way
    # => regenerate
    print $outhandle "$ifilename modified more recently than cached version\n";

    ($regenerated,$result,$had_error) 
        = regenerate_general_cmd($command,$ifilename,$ofilename,$options);
    }
    else {
    # file exists => check to see if command to generate it has changed

    if (open (ARGSIN,"<$args_filename")) {
        my $prev_command = <ARGSIN>;
        chomp($prev_command);

        close(ARGSIN);

        if (defined $prev_command) {
        # if commands are different

        # but first apply the gsdl environment variable substitute, for portability
        my $gsdl3srchome = $ENV{'GSDL3SRCHOME'};
        my $gsdl_substitute_command = $command;
        $gsdl_substitute_command =~ s@$gsdl3srchome@\$GSDL3SRCHOME@g;
        
        if ($prev_command ne $gsdl_substitute_command) {
            # need to rerun command
            ($regenerated,$result,$had_error) 
            = regenerate_general_cmd($command,$ifilename,$ofilename,$options);
        }
        else {
            my ($ofile) = ($ofilename =~ m/^.*(cached.*)$/);

            my $ofile_no_dir = basename($ofile);
            print $outhandle "  $message_prefix: Cached file $ofile_no_dir already exists.\n";
            print $outhandle "  $message_prefix: No need to regenerate $ofile\n" if ($verbosity > 2);
           
            if ((defined $options->{'cache_mode'}) 
            && $options->{'cache_mode'} eq "without_result") {
            $result = "";           
            }
            else {
            # Read in the cached result lines and join them into a single string
            my $result_filename = "$ofilename.result";
            if (open(RESIN, "<$result_filename"))
            {
                my @result_lines = <RESIN>;
                $result = join("\n", @result_lines);
                close(RESIN);
            }
            else
            {
                print $outhandle "  $message_prefix: Error, failed to obtain cached result from $result_filename.\n";
            }
            }
        }
            
        }
    }
    else {
        print $outhandle "  $message_prefix: No cached previous args found.  Regenerating $ofilename\n";

        ($regenerated,$result,$had_error) 
        = regenerate_general_cmd($command,$ifilename,$ofilename,$options);
    }
    }

    return ($regenerated,$result,$had_error);
}


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