lib/perl5/5.8.8/ExtUtils/Constant/Utils.pm

   1 package ExtUtils::Constant::Utils;
   2
   3 use strict;
   4 use vars qw($VERSION @EXPORT_OK @ISA $is_perl56);
   5 use Carp;
   6
   7 @ISA = 'Exporter';
   8 @EXPORT_OK = qw(C_stringify perl_stringify);
   9 $VERSION = '0.01';
  10
  11 $is_perl56 = ($] < 5.007 && $] > 5.005_50);
  12
  13 =head1 NAME
  14
  15 ExtUtils::Constant::Utils - helper functions for ExtUtils::Constant
  16
  17 =head1 SYNOPSIS
  18
  19     use ExtUtils::Constant::Utils qw (C_stringify);
  20     $C_code = C_stringify $stuff;
  21
  22 =head1 DESCRIPTION
  23
  24 ExtUtils::Constant::Utils packages up utility subroutines used by
  25 ExtUtils::Constant, ExtUtils::Constant::Base and derived classes. All its
  26 functions are explicitly exportable.
  27
  28 =head1 USAGE
  29
  30 =over 4
  31
  32 =item C_stringify NAME
  33
  34 A function which returns a 7 bit ASCII correctly \ escaped version of the
  35 string passed suitable for C's "" or ''. It will die if passed Unicode
  36 characters.
  37
  38 =cut
  39
  40 # Hopefully make a happy C identifier.
  41 sub C_stringify {
  42   local $_ = shift;
  43   return unless defined $_;
  44   # grr 5.6.1
  45   confess "Wide character in '$_' intended as a C identifier"
  46     if tr/\0-\377// != length;
  47   # grr 5.6.1 moreso because its regexps will break on data that happens to
  48   # be utf8, which includes my 8 bit test cases.
  49   $_ = pack 'C*', unpack 'U*', $_ . pack 'U*' if $is_perl56;
  50   s/\\/\\\\/g;
  51   s/([\"\'])/\\$1/g;    # Grr. fix perl mode.
  52   s/\n/\\n/g;           # Ensure newlines don't end up in octal
  53   s/\r/\\r/g;
  54   s/\t/\\t/g;
  55   s/\f/\\f/g;
  56   s/\a/\\a/g;
  57   s/([^\0-\177])/sprintf "\\%03o", ord $1/ge;
  58   unless ($] < 5.006) {
  59     # This will elicit a warning on 5.005_03 about [: :] being reserved unless
  60     # I cheat
  61     my $cheat = '([[:^print:]])';
  62     s/$cheat/sprintf "\\%03o", ord $1/ge;
  63   } else {
  64     require POSIX;
  65     s/([^A-Za-z0-9_])/POSIX::isprint($1) ? $1 : sprintf "\\%03o", ord $1/ge;
  66   }
  67   $_;
  68 }
  69
  70 =item perl_stringify NAME
  71
  72 A function which returns a 7 bit ASCII correctly \ escaped version of the
  73 string passed suitable for a perl "" string.
  74
  75 =cut
  76
  77 # Hopefully make a happy perl identifier.
  78 sub perl_stringify {
  79   local $_ = shift;
  80   return unless defined $_;
  81   s/\\/\\\\/g;
  82   s/([\"\'])/\\$1/g;    # Grr. fix perl mode.
  83   s/\n/\\n/g;           # Ensure newlines don't end up in octal
  84   s/\r/\\r/g;
  85   s/\t/\\t/g;
  86   s/\f/\\f/g;
  87   s/\a/\\a/g;
  88   unless ($] < 5.006) {
  89     if ($] > 5.007) {
  90       s/([^\0-\177])/sprintf "\\x{%X}", ord $1/ge;
  91     } else {
  92       # Grr 5.6.1. And I don't think I can use utf8; to force the regexp
  93       # because 5.005_03 will fail.
  94       # This is grim, but I also can't split on //
  95       my $copy;
  96       foreach my $index (0 .. length ($_) - 1) {
  97         my $char = substr ($_, $index, 1);
  98         $copy .= ($char le "\177") ? $char : sprintf "\\x{%X}", ord $char;
  99       }
 100       $_ = $copy;
 101     }
 102     # This will elicit a warning on 5.005_03 about [: :] being reserved unless
 103     # I cheat
 104     my $cheat = '([[:^print:]])';
 105     s/$cheat/sprintf "\\%03o", ord $1/ge;
 106   } else {
 107     # Turns out "\x{}" notation only arrived with 5.6
 108     s/([^\0-\177])/sprintf "\\x%02X", ord $1/ge;
 109     require POSIX;
 110     s/([^A-Za-z0-9_])/POSIX::isprint($1) ? $1 : sprintf "\\%03o", ord $1/ge;
 111   }
 112   $_;
 113 }
 114
 115 1;
 116 __END__
 117
 118 =back
 119
 120 =head1 AUTHOR
 121
 122 Nicholas Clark <nick@ccl4.org> based on the code in C<h2xs> by Larry Wall and
 123 others