xref: /netbsd-src/external/gpl3/autoconf/dist/lib/Autom4te/General.pm (revision d874e91932377fc40d53f102e48fc3ee6f4fe9de)
1# autoconf -- create `configure' using m4 macros
2# Copyright (C) 2001-2004, 2006-2007, 2009-2012 Free Software
3# Foundation, Inc.
4
5# This program is free software: you can redistribute it and/or modify
6# it under the terms of the GNU General Public License as published by
7# the Free Software Foundation, either version 3 of the License, or
8# (at your option) any later version.
9
10# This program is distributed in the hope that it will be useful,
11# but WITHOUT ANY WARRANTY; without even the implied warranty of
12# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13# GNU General Public License for more details.
14
15# You should have received a copy of the GNU General Public License
16# along with this program.  If not, see <http://www.gnu.org/licenses/>.
17
18package Autom4te::General;
19
20=head1 NAME
21
22Autom4te::General - general support functions for Autoconf
23
24=head1 SYNOPSIS
25
26  use Autom4te::General
27
28=head1 DESCRIPTION
29
30This perl module provides various general purpose support functions
31used in several executables of the Autoconf package.
32
33=cut
34
35use 5.006;
36use Exporter;
37use Autom4te::ChannelDefs;
38use Autom4te::Channels;
39use Autom4te::Getopt ();
40use File::Basename;
41use File::Path ();
42use File::stat;
43use IO::File;
44use Carp;
45use strict;
46
47use vars qw (@ISA @EXPORT);
48
49@ISA = qw (Exporter);
50
51# Variables we define and export.
52my @export_vars =
53  qw ($debug $force $help $me $tmp $verbose $version);
54
55# Functions we define and export.
56my @export_subs =
57  qw (&debug
58      &getopt &shell_quote &mktmpdir
59      &uniq);
60
61# Functions we forward (coming from modules we use).
62my @export_forward_subs =
63  qw (&basename &dirname &fileparse);
64
65@EXPORT = (@export_vars, @export_subs, @export_forward_subs);
66
67
68# Variable we share with the main package.  Be sure to have a single
69# copy of them: using `my' together with multiple inclusion of this
70# package would introduce several copies.
71
72=head2 Global Variables
73
74=over 4
75
76=item C<$debug>
77
78Set this variable to 1 if debug messages should be enabled.  Debug
79messages are meant for developers only, or when tracking down an
80incorrect execution.
81
82=cut
83
84use vars qw ($debug);
85$debug = 0;
86
87=item C<$force>
88
89Set this variable to 1 to recreate all the files, or to consider all
90the output files are obsolete.
91
92=cut
93
94use vars qw ($force);
95$force = undef;
96
97=item C<$help>
98
99Set to the help message associated with the option C<--help>.
100
101=cut
102
103use vars qw ($help);
104$help = undef;
105
106=item C<$me>
107
108The name of this application, for diagnostic messages.
109
110=cut
111
112use vars qw ($me);
113$me = basename ($0);
114
115=item C<$tmp>
116
117The name of the temporary directory created by C<mktmpdir>.  Left
118C<undef> otherwise.
119
120=cut
121
122# Our tmp dir.
123use vars qw ($tmp);
124$tmp = undef;
125
126=item C<$verbose>
127
128Enable verbosity messages.  These messages are meant for ordinary
129users, and typically make explicit the steps being performed.
130
131=cut
132
133use vars qw ($verbose);
134$verbose = 0;
135
136=item C<$version>
137
138Set to the version message associated to the option C<--version>.
139
140=cut
141
142use vars qw ($version);
143$version = undef;
144
145=back
146
147=cut
148
149
150
151## ----- ##
152## END.  ##
153## ----- ##
154
155=head2 Functions
156
157=over 4
158
159=item C<END>
160
161Filter Perl's exit codes, delete any temporary directory (unless
162C<$debug>), and exit nonzero whenever closing C<STDOUT> fails.
163
164=cut
165
166# END
167# ---
168sub END
169{
170  # $? contains the exit status we will return.
171  # It was set using one of the following ways:
172  #
173  #  1) normal termination
174  #     this sets $? = 0
175  #  2) calling `exit (n)'
176  #     this sets $? = n
177  #  3) calling die or friends (croak, confess...):
178  #     a) when $! is non-0
179  #        this set $? = $!
180  #     b) when $! is 0 but $? is not
181  #        this sets $? = ($? >> 8)   (i.e., the exit code of the
182  #        last program executed)
183  #     c) when both $! and $? are 0
184  #        this sets $? = 255
185  #
186  # Cases 1), 2), and 3b) are fine, but we prefer $? = 1 for 3a) and 3c).
187  my $status = $?;
188  $status = 1 if ($! && $! == $?) || $? == 255;
189  # (Note that we cannot safely distinguish calls to `exit (n)'
190  # from calls to die when `$! = n'.  It's not big deal because
191  # we only call `exit (0)' or `exit (1)'.)
192
193  if (!$debug && defined $tmp && -d $tmp)
194    {
195      local $SIG{__WARN__} = sub { $status = 1; warn $_[0] };
196      File::Path::rmtree $tmp;
197    }
198
199  # This is required if the code might send any output to stdout
200  # E.g., even --version or --help.  So it's best to do it unconditionally.
201  if (! close STDOUT)
202    {
203      print STDERR "$me: closing standard output: $!\n";
204      $? = 1;
205      return;
206    }
207
208  $? = $status;
209}
210
211
212## ----------- ##
213## Functions.  ##
214## ----------- ##
215
216
217=item C<debug (@message)>
218
219If the debug mode is enabled (C<$debug> and C<$verbose>), report the
220C<@message> on C<STDERR>, signed with the name of the program.
221
222=cut
223
224# &debug(@MESSAGE)
225# ----------------
226# Messages displayed only if $DEBUG and $VERBOSE.
227sub debug (@)
228{
229  print STDERR "$me: ", @_, "\n"
230    if $verbose && $debug;
231}
232
233
234=item C<getopt (%option)>
235
236Wrapper around C<Autom4te::Getopt::parse_options>.  In addition to
237the user C<option>s, support C<-h>/C<--help>, C<-V>/C<--version>,
238C<-v>/C<--verbose>, C<-d>/C<--debug>, C<-f>/C<--force>.  Conform to
239the GNU Coding Standards for error messages.
240
241=cut
242
243# getopt (%OPTION)
244# ----------------
245# Handle the %OPTION, plus all the common options.
246sub getopt (%)
247{
248  my (%option) = @_;
249  %option = ("h|help"     => sub { print $help; exit 0 },
250	     "V|version"  => sub { print $version; exit 0 },
251
252	     "v|verbose"  => sub { ++$verbose },
253	     "d|debug"    => sub { ++$debug },
254	     'f|force'    => \$force,
255
256	     # User options last, so that they have precedence.
257	     %option);
258  Autom4te::Getopt::parse_options (%option);
259
260  setup_channel 'note', silent => !$verbose;
261  setup_channel 'verb', silent => !$verbose;
262}
263
264
265=item C<shell_quote ($file_name)>
266
267Quote C<$file_name> for the shell.
268
269=cut
270
271# $FILE_NAME
272# shell_quote ($FILE_NAME)
273# ------------------------
274# If the string $S is a well-behaved file name, simply return it.
275# If it contains white space, quotes, etc., quote it, and return
276# the new string.
277sub shell_quote($)
278{
279  my ($s) = @_;
280  if ($s =~ m![^\w+/.,-]!)
281    {
282      # Convert each single quote to '\''
283      $s =~ s/\'/\'\\\'\'/g;
284      # Then single quote the string.
285      $s = "'$s'";
286    }
287  return $s;
288}
289
290=item C<mktmpdir ($signature)>
291
292Create a temporary directory which name is based on C<$signature>.
293Store its name in C<$tmp>.  C<END> is in charge of removing it, unless
294C<$debug>.
295
296=cut
297
298# mktmpdir ($SIGNATURE)
299# ---------------------
300sub mktmpdir ($)
301{
302  my ($signature) = @_;
303  my $TMPDIR = $ENV{'TMPDIR'} || '/tmp';
304  my $quoted_tmpdir = shell_quote ($TMPDIR);
305
306  # If mktemp supports dirs, use it.
307  $tmp = `(umask 077 &&
308	   mktemp -d $quoted_tmpdir/"${signature}XXXXXX") 2>/dev/null`;
309  chomp $tmp;
310
311  if (!$tmp || ! -d $tmp)
312    {
313      $tmp = "$TMPDIR/$signature" . int (rand 10000) . ".$$";
314      mkdir $tmp, 0700
315	or croak "$me: cannot create $tmp: $!\n";
316    }
317
318  print STDERR "$me:$$: working in $tmp\n"
319    if $debug;
320}
321
322
323=item C<uniq (@list)>
324
325Return C<@list> with no duplicates, keeping only the first
326occurrences.
327
328=cut
329
330# @RES
331# uniq (@LIST)
332# ------------
333sub uniq (@)
334{
335  my @res = ();
336  my %seen = ();
337  foreach my $item (@_)
338    {
339      if (! exists $seen{$item})
340	{
341	  $seen{$item} = 1;
342	  push (@res, $item);
343	}
344    }
345  return wantarray ? @res : "@res";
346}
347
348
349=item C<handle_exec_errors ($command)>
350
351Display an error message for C<$command>, based on the content of
352C<$?> and C<$!>.
353
354=cut
355
356
357# handle_exec_errors ($COMMAND)
358# -----------------------------
359sub handle_exec_errors ($)
360{
361  my ($command) = @_;
362
363  $command = (split (' ', $command))[0];
364  if ($!)
365    {
366      error "failed to run $command: $!";
367    }
368  else
369    {
370      use POSIX qw (WIFEXITED WEXITSTATUS WIFSIGNALED WTERMSIG);
371
372      if (WIFEXITED ($?))
373	{
374	  my $status = WEXITSTATUS ($?);
375	  # WIFEXITED and WEXITSTATUS can alter $!, reset it so that
376	  # error() actually propagates the command's exit status, not $!.
377	  $! = 0;
378	  error "$command failed with exit status: $status";
379	}
380      elsif (WIFSIGNALED ($?))
381	{
382	  my $signal = WTERMSIG ($?);
383	  # In this case we prefer to exit with status 1.
384	  $! = 1;
385	  error "$command terminated by signal: $signal";
386	}
387      else
388	{
389	  error "$command exited abnormally";
390	}
391    }
392}
393
394=back
395
396=head1 SEE ALSO
397
398L<Autom4te::XFile>
399
400=head1 HISTORY
401
402Written by Alexandre Duret-Lutz E<lt>F<adl@gnu.org>E<gt> and Akim
403Demaille E<lt>F<akim@freefriends.org>E<gt>.
404
405=cut
406
407
408
4091; # for require
410
411### Setup "GNU" style for perl-mode and cperl-mode.
412## Local Variables:
413## perl-indent-level: 2
414## perl-continued-statement-offset: 2
415## perl-continued-brace-offset: 0
416## perl-brace-offset: 0
417## perl-brace-imaginary-offset: 0
418## perl-label-offset: -2
419## cperl-indent-level: 2
420## cperl-brace-offset: 0
421## cperl-continued-brace-offset: 0
422## cperl-label-offset: -2
423## cperl-extra-newline-before-brace: t
424## cperl-merge-trailing-else: nil
425## cperl-continued-statement-offset: 2
426## End:
427