From Code to Community: Sponsoring The Perl and Raku Conference 2025 Learn more

NWCLARK / ExtUtils-Constant-0.25 / lib / ExtUtils / Constant / Utils.pm 

            

              
1
2
3
4
5
6
7
8
9
10
11
12
13
—
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
—
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
—
129
130
131
132
133
134
135

              
package ExtUtils::Constant::Utils;
use strict;
use vars qw($VERSION @EXPORT_OK @ISA);
use Carp;
@ISA = 'Exporter';
@EXPORT_OK = qw(C_stringify perl_stringify);
$VERSION = '0.04';
use constant is_perl55 => ($] < 5.005_50);
use constant is_perl56 => ($] < 5.007 && $] > 5.005_50);
use constant is_sane_perl => $] > 5.007;
=head1 NAME
ExtUtils::Constant::Utils - helper functions for ExtUtils::Constant
=head1 SYNOPSIS
    use ExtUtils::Constant::Utils qw (C_stringify);
    $C_code = C_stringify $stuff;
=head1 DESCRIPTION
ExtUtils::Constant::Utils packages up utility subroutines used by
ExtUtils::Constant, ExtUtils::Constant::Base and derived classes. All its
functions are explicitly exportable.
=head1 USAGE
=over 4
=item C_stringify NAME
A function which returns a 7 bit ASCII correctly \ escaped version of the
string passed suitable for C's "" or ''. It will die if passed Unicode
characters.
=cut
# Hopefully make a happy C identifier.
sub C_stringify {
  local $_ = shift;
  return unless defined $_;
  # grr 5.6.1
  confess "Wide character in '$_' intended as a C identifier"
    if tr/\0-\377// != length;
  # grr 5.6.1 more so because its regexps will break on data that happens to
  # be utf8, which includes my 8 bit test cases.
  $_ = pack 'C*', unpack 'U*', $_ . pack 'U*' if is_perl56;
  s/\\/\\\\/g;
  s/([\"\'])/\\$1/g;    # Grr. fix perl mode.
  s/\n/\\n/g;           # Ensure newlines don't end up in octal
  s/\r/\\r/g;
  s/\t/\\t/g;
  s/\f/\\f/g;
  s/\a/\\a/g;
  unless (is_perl55) {
    # This will elicit a warning on 5.005_03 about [: :] being reserved unless
    # I cheat
    my $cheat = '([[:^print:]])';
    if (ord('A') == 193) { # EBCDIC has no ^\0-\177 workalike.
      s/$cheat/sprintf "\\%03o", ord $1/ge;
    } else {
      s/([^\0-\177])/sprintf "\\%03o", ord $1/ge;
    }
    s/$cheat/sprintf "\\%03o", ord $1/ge;
  } else {
    require POSIX;
    s/([^A-Za-z0-9_])/POSIX::isprint($1) ? $1 : sprintf "\\%03o", ord $1/ge;
  }
  $_;
}
=item perl_stringify NAME
A function which returns a 7 bit ASCII correctly \ escaped version of the
string passed suitable for a perl "" string.
=cut
# Hopefully make a happy perl identifier.
sub perl_stringify {
  local $_ = shift;
  return unless defined $_;
  s/\\/\\\\/g;
  s/([\"\'])/\\$1/g;    # Grr. fix perl mode.
  s/\n/\\n/g;           # Ensure newlines don't end up in octal
  s/\r/\\r/g;
  s/\t/\\t/g;
  s/\f/\\f/g;
  s/\a/\\a/g;
  unless (is_perl55) {
    # This will elicit a warning on 5.005_03 about [: :] being reserved unless
    # I cheat
    my $cheat = '([[:^print:]])';
    if (is_sane_perl) {
        if (ord('A') == 193) { # EBCDIC has no ^\0-\177 workalike.
            s/$cheat/sprintf "\\x{%X}", ord $1/ge;
        } else {
            s/([^\0-\177])/sprintf "\\x{%X}", ord $1/ge;
        }
    } else {
      # Grr 5.6.1. And I don't think I can use utf8; to force the regexp
      # because 5.005_03 will fail.
      # This is grim, but I also can't split on //
      my $copy;
      foreach my $index (0 .. length ($_) - 1) {
        my $char = substr ($_, $index, 1);
        $copy .= ($char le "\177") ? $char : sprintf "\\x{%X}", ord $char;
      }
      $_ = $copy;
    }
    s/$cheat/sprintf "\\%03o", ord $1/ge;
  } else {
    # Turns out "\x{}" notation only arrived with 5.6
    s/([^\0-\177])/sprintf "\\x%02X", ord $1/ge;
    require POSIX;
    s/([^A-Za-z0-9_])/POSIX::isprint($1) ? $1 : sprintf "\\%03o", ord $1/ge;
  }
  $_;
}
1;
__END__
=back
=head1 AUTHOR
Nicholas Clark <nick@ccl4.org> based on the code in C<h2xs> by Larry Wall and
others