1# autoconf -- create `configure' using m4 macros
2# Copyright (C) 2001, 2002, 2003, 2004, 2006 Free Software Foundation, Inc.
3
4# This program is free software; you can redistribute it and/or modify
5# it under the terms of the GNU General Public License as published by
6# the Free Software Foundation; either version 2, or (at your option)
7# any later version.
8
9# This program is distributed in the hope that it will be useful,
10# but WITHOUT ANY WARRANTY; without even the implied warranty of
11# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12# GNU General Public License for more details.
13
14# You should have received a copy of the GNU General Public License
15# along with this program; if not, write to the Free Software
16# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17# 02110-1301, USA.
18
19package Autom4te::General;
20
21=head1 NAME
22
23Autom4te::General - general support functions for Autoconf and Automake
24
25=head1 SYNOPSIS
26
27  use Autom4te::General
28
29=head1 DESCRIPTION
30
31This perl module provides various general purpose support functions
32used in several executables of the Autoconf and Automake packages.
33
34=cut
35
36use 5.005_03;
37use Exporter;
38use Autom4te::ChannelDefs;
39use Autom4te::Channels;
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 $version);
54
55# Functions we define and export.
56my @export_subs =
57  qw (&debug
58      &getopt &mktmpdir
59      &uniq);
60
61# Functions we forward (coming from modules we use).
62my @export_forward_subs =
63  qw (&basename &dirname &fileparse);
64
65@EXPORT = (@export_vars, @export_subs, @export_forward_subs);
66
67
68# Variable we share with the main package.  Be sure to have a single
69# copy of them: using `my' together with multiple inclusion of this
70# package would introduce several copies.
71
72=head2 Global Variables
73
74=over 4
75
76=item C<$debug>
77
78Set this variable to 1 if debug messages should be enabled.  Debug
79messages are meant for developpers 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 to the option C<--help>.
100
101=cut
102
103use vars qw ($help);
104$help = undef;
105
106=item C<$me>
107
108The name of this application, as should be used in diagostic messages.
109
110=cut
111
112use vars qw ($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<Getopt::Long>.  In addition to the user C<option>s,
237support C<-h>/C<--help>, C<-V>/C<--version>, C<-v>/C<--verbose>,
238C<-d>/C<--debug>, C<-f>/C<--force>.  Conform to the GNU Coding
239Standards for error messages.  Try to work around a weird behavior
240from C<Getopt::Long> to preserve C<-> as an C<@ARGV> instead of
241rejecting it as a broken option.
242
243=cut
244
245# getopt (%OPTION)
246# ----------------
247# Handle the %OPTION, plus all the common options.
248# Work around Getopt bugs wrt `-'.
249sub getopt (%)
250{
251  my (%option) = @_;
252  use Getopt::Long;
253
254  # F*k.  Getopt seems bogus and dies when given `-' with `bundling'.
255  # If fixed some day, use this: '' => sub { push @ARGV, "-" }
256  my $stdin = grep /^-$/, @ARGV;
257  @ARGV = grep !/^-$/, @ARGV;
258  %option = ("h|help"     => sub { print $help; exit 0 },
259	     "V|version"  => sub { print $version; exit 0 },
260
261	     "v|verbose"  => sub { ++$verbose },
262	     "d|debug"    => sub { ++$debug },
263	     'f|force'    => \$force,
264
265	     # User options last, so that they have precedence.
266	     %option);
267  Getopt::Long::Configure ("bundling", "pass_through");
268  GetOptions (%option)
269    or exit 1;
270
271  foreach (grep { /^-./ } @ARGV)
272    {
273      print STDERR "$0: unrecognized option `$_'\n";
274      print STDERR "Try `$0 --help' for more information.\n";
275      exit (1);
276    }
277
278  push @ARGV, '-'
279    if $stdin;
280
281  setup_channel 'note', silent => !$verbose;
282  setup_channel 'verb', silent => !$verbose;
283}
284
285
286=item C<mktmpdir ($signature)>
287
288Create a temporary directory which name is based on C<$signature>.
289Store its name in C<$tmp>.  C<END> is in charge of removing it, unless
290C<$debug>.
291
292=cut
293
294# mktmpdir ($SIGNATURE)
295# ---------------------
296sub mktmpdir ($)
297{
298  my ($signature) = @_;
299  my $TMPDIR = $ENV{'TMPDIR'} || '/tmp';
300
301  # If mktemp supports dirs, use it.
302  $tmp = `(umask 077 &&
303	   mktemp -d "$TMPDIR/${signature}XXXXXX") 2>/dev/null`;
304  chomp $tmp;
305
306  if (!$tmp || ! -d $tmp)
307    {
308      $tmp = "$TMPDIR/$signature" . int (rand 10000) . ".$$";
309      mkdir $tmp, 0700
310	or croak "$me: cannot create $tmp: $!\n";
311    }
312
313  print STDERR "$me:$$: working in $tmp\n"
314    if $debug;
315}
316
317
318=item C<uniq (@list)>
319
320Return C<@list> with no duplicates, keeping only the first
321occurrences.
322
323=cut
324
325# @RES
326# uniq (@LIST)
327# ------------
328sub uniq (@)
329{
330  my @res = ();
331  my %seen = ();
332  foreach my $item (@_)
333    {
334      if (! exists $seen{$item})
335	{
336	  $seen{$item} = 1;
337	  push (@res, $item);
338	}
339    }
340  return wantarray ? @res : "@res";
341}
342
343
344=item C<handle_exec_errors ($command)>
345
346Display an error message for C<$command>, based on the content of
347C<$?> and C<$!>.
348
349=cut
350
351
352# handle_exec_errors ($COMMAND)
353# -----------------------------
354sub handle_exec_errors ($)
355{
356  my ($command) = @_;
357
358  $command = (split (' ', $command))[0];
359  if ($!)
360    {
361      error "failed to run $command: $!";
362    }
363  else
364    {
365      use POSIX qw (WIFEXITED WEXITSTATUS WIFSIGNALED WTERMSIG);
366
367      if (WIFEXITED ($?))
368	{
369	  my $status = WEXITSTATUS ($?);
370	  # WIFEXITED and WEXITSTATUS can alter $!, reset it so that
371	  # error() actually propagates the command's exit status, not $!.
372	  $! = 0;
373	  error "$command failed with exit status: $status";
374	}
375      elsif (WIFSIGNALED ($?))
376	{
377	  my $signal = WTERMSIG ($?);
378	  # In this case we prefer to exit with status 1.
379	  $! = 1;
380	  error "$command terminated by signal: $signal";
381	}
382      else
383	{
384	  error "$command exited abnormally";
385	}
386    }
387}
388
389=back
390
391=head1 SEE ALSO
392
393L<Autom4te::XFile>
394
395=head1 HISTORY
396
397Written by Alexandre Duret-Lutz E<lt>F<adl@gnu.org>E<gt> and Akim
398Demaille E<lt>F<akim@freefriends.org>E<gt>.
399
400=cut
401
402
403
4041; # for require
405
406### Setup "GNU" style for perl-mode and cperl-mode.
407## Local Variables:
408## perl-indent-level: 2
409## perl-continued-statement-offset: 2
410## perl-continued-brace-offset: 0
411## perl-brace-offset: 0
412## perl-brace-imaginary-offset: 0
413## perl-label-offset: -2
414## cperl-indent-level: 2
415## cperl-brace-offset: 0
416## cperl-continued-brace-offset: 0
417## cperl-label-offset: -2
418## cperl-extra-newline-before-brace: t
419## cperl-merge-trailing-else: nil
420## cperl-continued-statement-offset: 2
421## End:
422