#!/usr/bin/perl

# RPM (and its source code) is covered under two separate licenses.

# The entire code base may be distributed under the terms of the GNU

# General Public License (GPL), which appears immediately below.

# Alternatively, all of the source code in the lib subdirectory of the

# RPM source code distribution as well as any code derived from that

# code may instead be distributed under the GNU Library General Public

# License (LGPL), at the choice of the distributor. The complete text

# of the LGPL appears at the bottom of this file.

# This alternatively is allowed to enable applications to be linked

# against the RPM library (commonly called librpm) without forcing

# such applications to be distributed under the GPL.

# Any questions regarding the licensing of RPM should be addressed to

# Erik Troan <ewt@redhat.com>.

# a simple makedepend like script for perl.

# To save development time I do not parse the perl grammar but

# instead just lex it looking for what I want.  I take special care to

# ignore comments and pod's.

# It would be much better if perl could tell us the dependencies of a

# given script.

# The filenames to scan are either passed on the command line or if

# that is empty they are passed via stdin.

# If there are strings in the file which match the pattern

#     m/^\s*\$RPM_Requires\s*=\s*["'](.*)['"]/i

# then these are treated as additional names which are required by the

# file and are printed as well.

# I plan to rewrite this in C so that perl is not required by RPM at

# build time.

# by Ken Estes Mail.com kestes@staff.mail.com

$HAVE_VERSION = 0;

eval { require version; $HAVE_VERSION = 1; };

if ("@ARGV") {

  foreach (@ARGV) {

    process_file($_);

  }

} else {

  # notice we are passed a list of filenames NOT as common in unix the

  # contents of the file.

  foreach (<>) {

    process_file($_);

  }

}

foreach $perlver (sort keys %perlreq) {

  print "perl >= $perlver\n";

}

foreach $module (sort keys %require) {

  if (length($require{$module}) == 0) {

    print "perl($module)\n";

  } else {

    # I am not using rpm3.0 so I do not want spaces around my

    # operators. Also I will need to change the processing of the

    # $RPM_* variable when I upgrade.

    print "perl($module) >= $require{$module}\n";

  }

}

exit 0;

sub add_require {

  my ($module, $newver) = @_;

  my $oldver = $require{$module};

  if ($oldver) {

    $require{$module} = $newver

      if ($HAVE_VERSION && $newver && version->new($oldver) < $newver);

  }

  else {

    $require{$module} = $newver;

  }

}

sub process_file {

  my ($file) = @_;

  chomp $file;

  if (!open(FILE, $file)) {

    warn("$0: Warning: Could not open file '$file' for reading: $!\n");

    return;

  }

  while (<FILE>) {

    # skip the "= <<" block

    if (m/^\s*(?:my\s*)?\$(?:.*)\s*=\s*<<\s*(["'`])(.+?)\1/ ||

        m/^\s*(?:my\s*)?\$(.*)\s*=\s*<<(\w+)\s*;/) {

      $tag = $2;

      while (<FILE>) {

        chomp;

        ( $_ eq $tag ) && last;

      }

      $_ = <FILE>;

    }

    # skip q{} quoted sections - just hope we don't have curly brackets

    # within the quote, nor an escaped hash mark that isn't a comment

    # marker, such as occurs right here. Draw the line somewhere.

    if ( m/^.*\Wq[qxwr]?\s*([{([#|\/])[^})\]#|\/]*$/ && ! m/^\s*(require|use)\s/ ) {

      $tag = $1;

      $tag =~ tr/{\(\[\#|\//})]#|\//;

      $tag = quotemeta($tag);

      while (<FILE>) {

        ( $_ =~ m/$tag/ ) && last;

      }

    }

    # skip the documentation

    # we should not need to have item in this if statement (it

    # properly belongs in the over/back section) but people do not

    # read the perldoc.

    if (/^=(head[1-4]|pod|for|item)/) {

      /^=cut/ && next while <FILE>;

    }

    if (/^=over/) {

      /^=back/ && next while <FILE>;

    }

    # skip the data section

    if (m/^__(DATA|END)__$/) {

      last;

    }

    # Each keyword can appear multiple times.  Don't

    #  bother with datastructures to store these strings,

    #  if we need to print it print it now.

    #

        # Again allow for "our".

    if (m/^\s*(our\s+)?\$RPM_Requires\s*=\s*["'](.*)['"]/i) {

      foreach $_ (split(/\s+/, $2)) {

        print "$_\n";

      }

    }

    my $modver_re = qr/[.0-9]+/;

    #

    # The (require|use) match further down in this subroutine will match lines

    # within a multi-line print or return statements.  So, let's skip over such

    # statements whose content should not be loading modules anyway. -BEF-

    #

    if (m/print(?:\s+|\s+\S+\s+)\<\<\s*(["'`])(.+?)\1/ ||

        m/print(\s+|\s+\S+\s+)\<\<(\w+)/ ||

	m/return(\s+)\<\<(\w+)/ ) {

        my $tag = $2;

        while (<FILE>) {

            chomp;

            ( $_ eq $tag ) && last;

        }

        $_ = <FILE>;

    }

    # Skip multiline print and assign statements

    if ( m/\$\S+\s*=\s*(")([^"\\]|(\\.))*$/ ||

         m/\$\S+\s*=\s*(')([^'\\]|(\\.))*$/ ||

         m/print\s+(")([^"\\]|(\\.))*$/ ||

         m/print\s+(')([^'\\]|(\\.))*$/ ) {

        my $quote = $1;

        while (<FILE>) {

          m/^([^\\$quote]|(\\.))*$quote/ && last;

        }

        $_ = <FILE>;

    }

    if (

# ouch could be in a eval, perhaps we do not want these since we catch

# an exception they must not be required

#   eval { require Term::ReadLine } or die $@;

#   eval "require Term::Rendezvous;" or die $@;

#   eval { require Carp } if defined $^S; # If error/warning during compilation,

        (m/^(\s*)         # we hope the inclusion starts the line

         (require|use)\s+(?!\{)     # do not want 'do {' loops

         # quotes around name are always legal

         ['"]?([\w:\.\/]+?)['"]?[\t; ]

         # the syntax for 'use' allows version requirements

         # the latter part is for "use base qw(Foo)" and friends special case

         \s*($modver_re|(qw\s*[(\/'"]\s*|['"])[^)\/"'\$]*?\s*[)\/"'])?

         /x)

       ) {

      my ($whitespace, $statement, $module, $version) = ($1, $2, $3, $4);

      # we only consider require statements that are flushed against

      # the left edge. any other require statements give too many

      # false positives, as they are usually inside of an if statement

      # as a fallback module or a rarely used option

      ($whitespace ne "" && $statement eq "require") && next;

      # if there is some interpolation of variables just skip this

      # dependency, we do not want

      #        do "$ENV{LOGDIR}/$rcfile";

      ($module =~ m/\$/) && next;

      # skip if the phrase was "use of" -- shows up in gimp-perl, et al.

      next if $module eq 'of';

      # if the module ends in a comma we probably caught some

      # documentation of the form 'check stuff,\n do stuff, clean

      # stuff.' there are several of these in the perl distribution

      ($module  =~ m/[,>]$/) && next;

      # if the module name starts in a dot it is not a module name.

      # Is this necessary?  Please give me an example if you turn this

      # back on.

      #      ($module =~ m/^\./) && next;

      # if the module starts with /, it is an absolute path to a file

      if ($module =~ m(^/)) {

        print "$module\n";

        next;

      }

      # sometimes people do use POSIX qw(foo), or use POSIX(qw(foo)) etc.

      # we can strip qw.*$, as well as (.*$:

      $module =~ s/qw.*$//;

      $module =~ s/\(.*$//;

      # if the module ends with .pm, strip it to leave only basename.

      $module =~ s/\.pm$//;

      # some perl programmers write 'require URI/URL;' when

      # they mean 'require URI::URL;'

      $module =~ s/\//::/;

      # trim off trailing parentheses if any.  Sometimes people pass

      # the module an empty list.

      $module =~ s/\(\s*\)$//;

      if ( $module =~ m/^v?([0-9._]+)$/ ) {

      # if module is a number then both require and use interpret that

      # to mean that a particular version of perl is specified

      my $ver = $1;

      if ($ver =~ /5.00/) {

        $perlreq{"0:$ver"} = 1;

        next;

      }

      else {

        $perlreq{"1:$ver"} = 1;

        next;

      }

      };

      # ph files do not use the package name inside the file.

      # perlmodlib documentation says:

      #       the .ph files made by h2ph will probably end up as

      #       extension modules made by h2xs.

      # so do not expend much effort on these.

      # there is no easy way to find out if a file named systeminfo.ph

      # will be included with the name sys/systeminfo.ph so only use the

      # basename of *.ph files

      ($module =~ m/\.ph$/) && next;

      # use base|parent qw(Foo) dependencies

      if ($statement eq "use" && ($module eq "base" || $module eq "parent")) {

        add_require($module, undef);

        if ($version =~ /^qw\s*[(\/'"]\s*([^)\/"']+?)\s*[)\/"']/) {

          add_require($_, undef) for split(' ', $1);

        }

        elsif ($version =~ /(["'])([^"']+)\1/) {

          add_require($2, undef);

        }

        next;

      }

      $version = undef unless $version =~ /^$modver_re$/o;

      add_require($module, $version);

    }

  }

  close(FILE) ||

    die("$0: Could not close file: '$file' : $!\n");

  return;

}