lib/Autom4te/General.pm - autoconf - Git at Google

 # autoconf -- create 'configure' using m4 macros
 # Copyright (C) 2001-2004, 2006-2007, 2009-2017, 2020-2024 Free Software
 # Foundation, Inc.

 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation, either version 3 of the License, or
 # (at your option) any later version.

 # This program is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 # GNU General Public License for more details.

 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <https://www.gnu.org/licenses/>.

 package Autom4te::General;

 =head1 NAME

 Autom4te::General - general support functions for Autoconf

 =head1 SYNOPSIS

   use Autom4te::General

 =head1 DESCRIPTION

 This perl module provides various general purpose support functions
 used in several executables of the Autoconf package.

 =cut

 use 5.006;
 use strict;
 use warnings FATAL => 'all';

 use Carp;
 use Exporter;
 use File::Basename;
 use File::Spec ();
 use File::stat;
 use File::Temp ();
 use IO::File;

 use Autom4te::ChannelDefs;
 use Autom4te::Channels;
 use Autom4te::Getopt ();

 our @ISA = qw (Exporter);

 # Variables we define and export.
 my @export_vars =
   qw ($debug $force $help $me $tmp $verbose $version);

 # Functions we define and export.
 my @export_subs =
   qw (&debug
       &getopt &shell_quote &mktmpdir
       &uniq);

 # Functions we forward (coming from modules we use).
 my @export_forward_subs =
   qw (&basename &dirname &fileparse);

 our @EXPORT = (@export_vars, @export_subs, @export_forward_subs);


 # Variable we share with the main package.  Be sure to have a single
 # copy of them: using 'my' together with multiple inclusion of this
 # package would introduce several copies.

 =head2 Global Variables

 =over 4

 =item C<$debug>

 Set this variable to 1 if debug messages should be enabled.  Debug
 messages are meant for developers only, or when tracking down an
 incorrect execution.

 =cut

 our $debug = 0;

 =item C<$force>

 Set this variable to 1 to recreate all the files, or to consider all
 the output files are obsolete.

 =cut

 our $force = undef;

 =item C<$help>

 Set to the help message associated with the option C<--help>.

 =cut

 our $help = undef;

 =item C<$me>

 The name of this application, for diagnostic messages.

 =cut

 our $me = basename ($0);

 =item C<$tmp>

 The name of the temporary directory created by C<mktmpdir>.  Left
 C<undef> otherwise.

 =cut

 # Our tmp dir.
 our $tmp = undef;

 =item C<$verbose>

 Enable verbosity messages.  These messages are meant for ordinary
 users, and typically make explicit the steps being performed.

 =cut

 our $verbose = 0;

 =item C<$version>

 Set to the version message associated to the option C<--version>.

 =cut

 our $version = undef;

 =back

 =cut


 ## ----- ##
 ## END.  ##
 ## ----- ##

 =head2 Functions

 =over 4

 =item C<END>

 Filter Perl's exit codes and exit nonzero whenever closing C<STDOUT> fails.

 =cut

 # END
 # ---
 sub END
 {
   # $? contains the exit status we will return.
   # It was set using one of the following ways:
   #
   #  1) normal termination
   #     this sets $? = 0
   #  2) calling 'exit (n)'
   #     this sets $? = n
   #  3) calling die or friends (croak, confess...):
   #     a) when $! is non-0
   #        this set $? = $!
   #     b) when $! is 0 but $? is not
   #        this sets $? = ($? >> 8)   (i.e., the exit code of the
   #        last program executed)
   #     c) when both $! and $? are 0
   #        this sets $? = 255
   #
   # Cases 1), 2), and 3b) are fine, but we prefer $? = 1 for 3a) and 3c).
   my $status = $?;
   $status = 1 if ($! && $! == $?) || $? == 255;
   # (Note that we cannot safely distinguish calls to 'exit (n)'
   # from calls to die when '$! = n'.  It's not big deal because
   # we only call 'exit (0)' or 'exit (1)'.)

   # This is required if the code might send any output to stdout
   # E.g., even --version or --help.  So it's best to do it unconditionally.
   if (! close STDOUT)
     {
       print STDERR "$me: closing standard output: $!\n";
       $? = 1;
       return;
     }

   $? = $status;
 }


 ## ----------- ##
 ## Functions.  ##
 ## ----------- ##


 =item C<debug (@message)>

 If the debug mode is enabled (C<$debug> and C<$verbose>), report the
 C<@message> on C<STDERR>, signed with the name of the program.

 =cut

 # &debug(@MESSAGE)
 # ----------------
 # Messages displayed only if $DEBUG and $VERBOSE.
 sub debug (@)
 {
   print STDERR "$me: ", @_, "\n"
     if $verbose && $debug;
 }


 =item C<getopt (%option)>

 Wrapper around C<Autom4te::Getopt::parse_options>.  In addition to
 the user C<option>s, support C<-h>/C<--help>, C<-V>/C<--version>,
 C<-v>/C<--verbose>, C<-d>/C<--debug>, C<-f>/C<--force>.  Conform to
 the GNU Coding Standards for error messages.

 =cut

 # getopt (%OPTION)
 # ----------------
 # Handle the %OPTION, plus all the common options.
 sub getopt (%)
 {
   my (%option) = @_;
   %option = ("h|help"     => sub { print $help; exit 0 },
 	     "V|version"  => sub { print $version; exit 0 },

 	     "v|verbose"  => sub { ++$verbose },
 	     "d|debug"    => sub { ++$debug },
 	     'f|force'    => \$force,

 	     # User options last, so that they have precedence.
 	     %option);
   Autom4te::Getopt::parse_options (%option);

   setup_channel 'note', silent => !$verbose;
   setup_channel 'verb', silent => !$verbose;
 }


 =item C<shell_quote ($file_name)>

 Quote C<$file_name> for the shell.

 =cut

 # $FILE_NAME
 # shell_quote ($FILE_NAME)
 # ------------------------
 # If the string $S is a well-behaved file name, simply return it.
 # If it contains white space, quotes, etc., quote it, and return
 # the new string.
 sub shell_quote($)
 {
   my ($s) = @_;
   if ($s =~ m![^\w+/.,-]!)
     {
       # Convert each single quote to '\''
       $s =~ s/\'/\'\\\'\'/g;
       # Then single quote the string.
       $s = "'$s'";
     }
   return $s;
 }

 =item C<mktmpdir ($signature)>

 Create a temporary directory which name is based on C<$signature>.
 Store its name in C<$tmp>.  It will be removed at program exit,
 unless C<$debug> is true.

 =cut

 # mktmpdir ($SIGNATURE)
 # ---------------------
 sub mktmpdir ($)
 {
   my ($signature) = @_;

   # Ensure that we refer to the temporary directory by absolute
   # pathname; most importantly, this ensures that C<do FILE> will
   # work whenever FILE is in $tmp, even when '.' is not in @INC
   # (perl 5.26 and later).
   my $TMPDIR = File::Spec->rel2abs (File::Spec->tmpdir ());
   $tmp = File::Temp::tempdir (
     $signature . "XXXXXX",
     DIR => $TMPDIR,
     CLEANUP => !$debug
   );

   print STDERR "$me:$$: working in $tmp\n"
     if $debug;

   return $tmp;
 }


 =item C<uniq (@list)>

 Return C<@list> with no duplicates, keeping only the first
 occurrences.

 =cut

 # @RES
 # uniq (@LIST)
 # ------------
 sub uniq (@)
 {
   my @res = ();
   my %seen = ();
   foreach my $item (@_)
     {
       if (! exists $seen{$item})
 	{
 	  $seen{$item} = 1;
 	  push (@res, $item);
 	}
     }
   return wantarray ? @res : "@res";
 }


 =item C<handle_exec_errors ($command)>

 Display an error message for C<$command>, based on the content of
 C<$?> and C<$!>.

 =cut


 # handle_exec_errors ($COMMAND)
 # -----------------------------
 sub handle_exec_errors ($)
 {
   my ($command) = @_;

   $command = (split (' ', $command))[0];
   if ($!)
     {
       error "failed to run $command: $!";
     }
   else
     {
       use POSIX qw (WIFEXITED WEXITSTATUS WIFSIGNALED WTERMSIG);

       if (WIFEXITED ($?))
 	{
 	  my $status = WEXITSTATUS ($?);
 	  # WIFEXITED and WEXITSTATUS can alter $!, reset it so that
 	  # error() actually propagates the command's exit status, not $!.
 	  $! = 0;
 	  error "$command failed with exit status: $status";
 	}
       elsif (WIFSIGNALED ($?))
 	{
 	  my $signal = WTERMSIG ($?);
 	  # In this case we prefer to exit with status 1.
 	  $! = 1;
 	  error "$command terminated by signal: $signal";
 	}
       else
 	{
 	  error "$command exited abnormally";
 	}
     }
 }

 =back

 =head1 SEE ALSO

 L<Autom4te::XFile>

 =head1 HISTORY

 Written by Alexandre Duret-Lutz E<lt>F<adl@gnu.org>E<gt> and Akim
 Demaille E<lt>F<akim@freefriends.org>E<gt>.

 =cut


 1; # for require

 ### Setup "GNU" style for perl-mode and cperl-mode.
 ## Local Variables:
 ## perl-indent-level: 2
 ## perl-continued-statement-offset: 2
 ## perl-continued-brace-offset: 0
 ## perl-brace-offset: 0
 ## perl-brace-imaginary-offset: 0
 ## perl-label-offset: -2
 ## cperl-indent-level: 2
 ## cperl-brace-offset: 0
 ## cperl-continued-brace-offset: 0
 ## cperl-label-offset: -2
 ## cperl-extra-newline-before-brace: t
 ## cperl-merge-trailing-else: nil
 ## cperl-continued-statement-offset: 2
 ## End:
	# autoconf -- create 'configure' using m4 macros
	# Copyright (C) 2001-2004, 2006-2007, 2009-2017, 2020-2024 Free Software
	# Foundation, Inc.

	# This program is free software: you can redistribute it and/or modify
	# it under the terms of the GNU General Public License as published by
	# the Free Software Foundation, either version 3 of the License, or
	# (at your option) any later version.

	# This program is distributed in the hope that it will be useful,
	# but WITHOUT ANY WARRANTY; without even the implied warranty of
	# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	# GNU General Public License for more details.

	# You should have received a copy of the GNU General Public License
	# along with this program. If not, see <https://www.gnu.org/licenses/>.

	package Autom4te::General;

	=head1 NAME

	Autom4te::General - general support functions for Autoconf

	=head1 SYNOPSIS

	use Autom4te::General

	=head1 DESCRIPTION

	This perl module provides various general purpose support functions
	used in several executables of the Autoconf package.

	=cut

	use 5.006;
	use strict;
	use warnings FATAL => 'all';

	use Carp;
	use Exporter;
	use File::Basename;
	use File::Spec ();
	use File::stat;
	use File::Temp ();
	use IO::File;

	use Autom4te::ChannelDefs;
	use Autom4te::Channels;
	use Autom4te::Getopt ();

	our @ISA = qw (Exporter);

	# Variables we define and export.
	my @export_vars =
	qw ($debug $force $help $me $tmp $verbose $version);

	# Functions we define and export.
	my @export_subs =
	qw (&debug
	&getopt &shell_quote &mktmpdir
	&uniq);

	# Functions we forward (coming from modules we use).
	my @export_forward_subs =
	qw (&basename &dirname &fileparse);

	our @EXPORT = (@export_vars, @export_subs, @export_forward_subs);


	# Variable we share with the main package. Be sure to have a single
	# copy of them: using 'my' together with multiple inclusion of this
	# package would introduce several copies.

	=head2 Global Variables

	=over 4

	=item C<$debug>

	Set this variable to 1 if debug messages should be enabled. Debug
	messages are meant for developers only, or when tracking down an
	incorrect execution.

	=cut

	our $debug = 0;

	=item C<$force>

	Set this variable to 1 to recreate all the files, or to consider all
	the output files are obsolete.

	=cut

	our $force = undef;

	=item C<$help>

	Set to the help message associated with the option C<--help>.

	=cut

	our $help = undef;

	=item C<$me>

	The name of this application, for diagnostic messages.

	=cut

	our $me = basename ($0);

	=item C<$tmp>

	The name of the temporary directory created by C<mktmpdir>. Left
	C<undef> otherwise.

	=cut

	# Our tmp dir.
	our $tmp = undef;

	=item C<$verbose>

	Enable verbosity messages. These messages are meant for ordinary
	users, and typically make explicit the steps being performed.

	=cut

	our $verbose = 0;

	=item C<$version>

	Set to the version message associated to the option C<--version>.

	=cut

	our $version = undef;

	=back

	=cut



	## ----- ##
	## END. ##
	## ----- ##

	=head2 Functions

	=over 4

	=item C<END>

	Filter Perl's exit codes and exit nonzero whenever closing C<STDOUT> fails.

	=cut

	# END
	# ---
	sub END
	{
	# $? contains the exit status we will return.
	# It was set using one of the following ways:
	#
	# 1) normal termination
	# this sets $? = 0
	# 2) calling 'exit (n)'
	# this sets $? = n
	# 3) calling die or friends (croak, confess...):
	# a) when $! is non-0
	# this set $? = $!
	# b) when $! is 0 but $? is not
	# this sets $? = ($? >> 8) (i.e., the exit code of the
	# last program executed)
	# c) when both $! and $? are 0
	# this sets $? = 255
	#
	# Cases 1), 2), and 3b) are fine, but we prefer $? = 1 for 3a) and 3c).
	my $status = $?;
	$status = 1 if ($! && $! == $?) \|\| $? == 255;
	# (Note that we cannot safely distinguish calls to 'exit (n)'
	# from calls to die when '$! = n'. It's not big deal because
	# we only call 'exit (0)' or 'exit (1)'.)

	# This is required if the code might send any output to stdout
	# E.g., even --version or --help. So it's best to do it unconditionally.
	if (! close STDOUT)
	{
	print STDERR "$me: closing standard output: $!\n";
	$? = 1;
	return;
	}

	$? = $status;
	}


	## ----------- ##
	## Functions. ##
	## ----------- ##


	=item C<debug (@message)>

	If the debug mode is enabled (C<$debug> and C<$verbose>), report the
	C<@message> on C<STDERR>, signed with the name of the program.

	=cut

	# &debug(@MESSAGE)
	# ----------------
	# Messages displayed only if $DEBUG and $VERBOSE.
	sub debug (@)
	{
	print STDERR "$me: ", @_, "\n"
	if $verbose && $debug;
	}


	=item C<getopt (%option)>

	Wrapper around C<Autom4te::Getopt::parse_options>. In addition to
	the user C<option>s, support C<-h>/C<--help>, C<-V>/C<--version>,
	C<-v>/C<--verbose>, C<-d>/C<--debug>, C<-f>/C<--force>. Conform to
	the GNU Coding Standards for error messages.

	=cut

	# getopt (%OPTION)
	# ----------------
	# Handle the %OPTION, plus all the common options.
	sub getopt (%)
	{
	my (%option) = @_;
	%option = ("h\|help" => sub { print $help; exit 0 },
	"V\|version" => sub { print $version; exit 0 },

	"v\|verbose" => sub { ++$verbose },
	"d\|debug" => sub { ++$debug },
	'f\|force' => \$force,

	# User options last, so that they have precedence.
	%option);
	Autom4te::Getopt::parse_options (%option);

	setup_channel 'note', silent => !$verbose;
	setup_channel 'verb', silent => !$verbose;
	}


	=item C<shell_quote ($file_name)>

	Quote C<$file_name> for the shell.

	=cut

	# $FILE_NAME
	# shell_quote ($FILE_NAME)
	# ------------------------
	# If the string $S is a well-behaved file name, simply return it.
	# If it contains white space, quotes, etc., quote it, and return
	# the new string.
	sub shell_quote($)
	{
	my ($s) = @_;
	if ($s =~ m![^\w+/.,-]!)
	{
	# Convert each single quote to '\''
	$s =~ s/\'/\'\\\'\'/g;
	# Then single quote the string.
	$s = "'$s'";
	}
	return $s;
	}

	=item C<mktmpdir ($signature)>

	Create a temporary directory which name is based on C<$signature>.
	Store its name in C<$tmp>. It will be removed at program exit,
	unless C<$debug> is true.

	=cut

	# mktmpdir ($SIGNATURE)
	# ---------------------
	sub mktmpdir ($)
	{
	my ($signature) = @_;

	# Ensure that we refer to the temporary directory by absolute
	# pathname; most importantly, this ensures that C<do FILE> will
	# work whenever FILE is in $tmp, even when '.' is not in @INC
	# (perl 5.26 and later).
	my $TMPDIR = File::Spec->rel2abs (File::Spec->tmpdir ());
	$tmp = File::Temp::tempdir (
	$signature . "XXXXXX",
	DIR => $TMPDIR,
	CLEANUP => !$debug
	);

	print STDERR "$me:$$: working in $tmp\n"
	if $debug;

	return $tmp;
	}


	=item C<uniq (@list)>

	Return C<@list> with no duplicates, keeping only the first
	occurrences.

	=cut

	# @RES
	# uniq (@LIST)
	# ------------
	sub uniq (@)
	{
	my @res = ();
	my %seen = ();
	foreach my $item (@_)
	{
	if (! exists $seen{$item})
	{
	$seen{$item} = 1;
	push (@res, $item);
	}
	}
	return wantarray ? @res : "@res";
	}


	=item C<handle_exec_errors ($command)>

	Display an error message for C<$command>, based on the content of
	C<$?> and C<$!>.

	=cut


	# handle_exec_errors ($COMMAND)
	# -----------------------------
	sub handle_exec_errors ($)
	{
	my ($command) = @_;

	$command = (split (' ', $command))[0];
	if ($!)
	{
	error "failed to run $command: $!";
	}
	else
	{
	use POSIX qw (WIFEXITED WEXITSTATUS WIFSIGNALED WTERMSIG);

	if (WIFEXITED ($?))
	{
	my $status = WEXITSTATUS ($?);
	# WIFEXITED and WEXITSTATUS can alter $!, reset it so that
	# error() actually propagates the command's exit status, not $!.
	$! = 0;
	error "$command failed with exit status: $status";
	}
	elsif (WIFSIGNALED ($?))
	{
	my $signal = WTERMSIG ($?);
	# In this case we prefer to exit with status 1.
	$! = 1;
	error "$command terminated by signal: $signal";
	}
	else
	{
	error "$command exited abnormally";
	}
	}
	}

	=back

	=head1 SEE ALSO

	L<Autom4te::XFile>

	=head1 HISTORY

	Written by Alexandre Duret-Lutz E<lt>F<adl@gnu.org>E<gt> and Akim
	Demaille E<lt>F<akim@freefriends.org>E<gt>.

	=cut



	1; # for require

	### Setup "GNU" style for perl-mode and cperl-mode.
	## Local Variables:
	## perl-indent-level: 2
	## perl-continued-statement-offset: 2
	## perl-continued-brace-offset: 0
	## perl-brace-offset: 0
	## perl-brace-imaginary-offset: 0
	## perl-label-offset: -2
	## cperl-indent-level: 2
	## cperl-brace-offset: 0
	## cperl-continued-brace-offset: 0
	## cperl-label-offset: -2
	## cperl-extra-newline-before-brace: t
	## cperl-merge-trailing-else: nil
	## cperl-continued-statement-offset: 2
	## End: