autom4te.in

autoconf是一个产生可以自动配置源代码包

#! @PERL@ -w
# -*- perl -*-
# @configure_input@

eval 'case $# in 0) exec @PERL@ -S "$0";; *) exec @PERL@ -S "$0" "$@";; esac'
    if 0;

# autom4te - Wrapper around M4 libraries.
# Copyright (C) 2001, 2002, 2003, 2005, 2006 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 2, 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, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
# 02110-1301, USA.


BEGIN
{
  my $datadir = $ENV{'autom4te_perllibdir'} || '@datadir@';
  unshift @INC, $datadir;

  # Override SHELL.  On DJGPP SHELL may not be set to a shell
  # that can handle redirection and quote arguments correctly,
  # e.g.: COMMAND.COM.  For DJGPP always use the shell that configure
  # has detected.
  $ENV{'SHELL'} = '@SHELL@' if ($^O eq 'dos');
}

use Autom4te::C4che;
use Autom4te::ChannelDefs;
use Autom4te::Channels;
use Autom4te::FileUtils;
use Autom4te::General;
use Autom4te::XFile;
use File::Basename;
use strict;

# Data directory.
my $datadir = $ENV{'AC_MACRODIR'} || '@datadir@';

# $LANGUAGE{LANGUAGE} -- Automatic options for LANGUAGE.
my %language;

my $output = '-';

# Mode of the output file except for traces.
my $mode = "0666";

# If melt, don't use frozen files.
my $melt = 0;

# Names of the cache directory, cache directory index, trace cache
# prefix, and output cache prefix.  And the IO objet for the index.
my $cache;
my $icache;
my $tcache;
my $ocache;
my $icache_file;

# The macros to trace mapped to their format, as specified by the
# user.
my %trace;

# The macros the user will want to trace in the future.
# We need `include' to get the included file, `m4_pattern_forbid' and
# `m4_pattern_allow' to check the output.
#
# FIXME: What about `sinclude'?
my @preselect = ('include',
		 'm4_pattern_allow', 'm4_pattern_forbid',
		 '_m4_warn');

# M4 include path.
my @include;

# Do we freeze?
my $freeze = 0;

# $M4.
my $m4 = $ENV{"M4"} || '@M4@';
# Some non-GNU m4's don't reject the --help option, so give them /dev/null.
fatal "need GNU m4 1.4 or later: $m4"
  if system "$m4 --help </dev/null 2>&1 | grep reload-state >/dev/null";

# Set some high recursion limit as the default limit, 250, has already
# been hit with AC_OUTPUT.  Don't override the user's choice.
$m4 .= ' --nesting-limit=1024'
  if " $m4 " !~ / (--nesting-limit(=[0-9]+)?|-L[0-9]*) /;


# @M4_BUILTIN -- M4 builtins and a useful comment.
my @m4_builtin = `echo dumpdef | $m4 2>&1 >/dev/null`;
map { s/:.*//;s/\W// } @m4_builtin;


# %M4_BUILTIN_ALTERNATE_NAME
# --------------------------
# The builtins are renamed, e.g., `define' is renamed `m4_define'.
# So map `define' to `m4_define' and conversely.
# Some macros don't follow this scheme: be sure to properly map to their
# alternate name too.
#
# This is because GNU M4 1.4's tracing of builtins is buggy.  When run on
# this input:
#
# | divert(-1)
# | changequote([, ])
# | define([m4_eval], defn([eval]))
# | eval(1)
# | m4_eval(2)
# | undefine([eval])
# | m4_eval(3)
#
# it behaves this way:
#
# | % m4 input.m4 -da -t eval
# | m4trace: -1- eval(1)
# | m4trace: -1- m4_eval(2)
# | m4trace: -1- m4_eval(3)
# | %
#
# Conversely:
#
# | % m4 input.m4 -da -t m4_eval
# | %
#
# So we will merge them, i.e.  tracing `BUILTIN' or tracing
# `m4_BUILTIN' will be the same: tracing both, but honoring the
# *last* trace specification.
#
# FIXME: This is not enough: in the output `$0' will be `BUILTIN'
# sometimes and `m4_BUILTIN' at others.  We should return a unique name,
# the one specified by the user.
#
# FIXME: To be absolutely rigorous, I would say that given that we
# _redefine_ divert (instead of _copying_ it), divert and the like
# should not be part of this list.
my %m4_builtin_alternate_name;
@m4_builtin_alternate_name{"$_", "m4_$_"} = ("m4_$_", "$_")
  foreach (grep { !/m4wrap|m4exit|dnl|ifelse|__.*__/ } @m4_builtin);
@m4_builtin_alternate_name{"ifelse", "m4_if"}   = ("m4_if", "ifelse");
@m4_builtin_alternate_name{"m4exit", "m4_exit"} = ("m4_exit", "m4exit");
@m4_builtin_alternate_name{"m4wrap", "m4_wrap"} = ("m4_wrap", "m4wrap");


# $HELP
# -----
$help = "Usage: $0 [OPTION] ... [FILES]

Run GNU M4 on the FILES, avoiding useless runs.  Output the traces if tracing,
the frozen file if freezing, otherwise the expansion of the FILES.

If some of the FILES are named \`FILE.m4f\' they are considered to be M4
frozen files of all the previous files (which are therefore not loaded).
If \`FILE.m4f\' is not found, then \`FILE.m4\' will be used, together with
all the previous files.

Some files may be optional, i.e., will only be processed if found in the
include path, but then must end in \`.m4?\';  the question mark is not part of
the actual file name.

Operation modes:
  -h, --help               print this help, then exit
  -V, --version            print version number, then exit
  -v, --verbose            verbosely report processing
  -d, --debug              don\'t remove temporary files
  -o, --output=FILE        save output in FILE (defaults to \`-\', stdout)
  -f, --force              don\'t rely on cached values
  -W, --warnings=CATEGORY  report the warnings falling in CATEGORY
  -l, --language=LANG      specify the set of M4 macros to use
  -C, --cache=DIRECTORY    preserve results for future runs in DIRECTORY
      --no-cache           disable the cache
  -m, --mode=OCTAL         change the non trace output file mode (0666)
  -M, --melt               don\'t use M4 frozen files

Languages include:
  \`Autoconf\'   create Autoconf configure scripts
  \`Autotest\'   create Autotest test suites
  \`M4sh\'       create M4sh shell scripts
  \`M4sugar\'    create M4sugar output

" . Autom4te::ChannelDefs::usage . "

The environment variables \`M4\' and \`WARNINGS\' are honored.

Library directories:
  -B, --prepend-include=DIR  prepend directory DIR to search path
  -I, --include=DIR          append directory DIR to search path

Tracing:
  -t, --trace=MACRO      report the MACRO invocations
  -p, --preselect=MACRO  prepare to trace MACRO in a future run

Freezing:
  -F, --freeze   produce an M4 frozen state file for FILES

Report bugs to <bug-autoconf\@gnu.org>.
";

# $VERSION
# --------
$version =  <<"EOF";
autom4te (@PACKAGE_NAME@) @VERSION@
Written by Akim Demaille.

Copyright (C) 2006 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
EOF


## ---------- ##
## Routines.  ##
## ---------- ##


# $OPTION
# files_to_options (@FILE)
# ------------------------
# Transform Autom4te conventions (e.g., using foo.m4f to designate a frozen
# file) into a suitable command line for M4 (e.g., using --reload-state).
sub files_to_options (@)
{
  my (@file) = @_;
  my @res;
  foreach my $file (@file)
    {
      if ($file =~ /\.m4f$/)
	{
	  push @res, "--reload-state=$file";
	}
      else
	{
	  push @res, $file;
	}
    }
  return join ' ', @res;
}


# load_configuration ($FILE)
# --------------------------
# Load the configuration $FILE.
sub load_configuration ($)
{
  my ($file) = @_;
  use Text::ParseWords;

  my $cfg = new Autom4te::XFile ($file);
  my $lang;
  while ($_ = $cfg->getline)
    {
      chomp;
      # Comments.
      next
	if /^\s*(\#.*)?$/;

      my @words = shellwords ($_);
      my $type = shift @words;
      if ($type eq 'begin-language:')
	{
	  fatal "$file:$.: end-language missing for: $lang"
	    if defined $lang;
	  $lang = lc $words[0];
	}
      elsif ($type eq 'end-language:')
	{
	  error "$file:$.: end-language mismatch: $lang"
	    if $lang ne lc $words[0];
	  $lang = undef;
	}
      elsif ($type eq 'args:')
	{
	  fatal "$file:$.: no current language"
	    unless defined $lang;
	  push @{$language{$lang}}, @words;
	}
      else
	{
	  error "$file:$.: unknown directive: $type";
	}
    }
}


# parse_args ()
# -------------
# Process any command line arguments.
sub parse_args ()
{
  # We want to look for the early options, which should not be found
  # in the configuration file.  Prepend to the user arguments.
  # Perform this repeatedly so that we can use --language in language
  # definitions.  Beware that there can be several --language
  # invocations.
  my @language;
  do {
    @language = ();
    use Getopt::Long;
    Getopt::Long::Configure ("pass_through", "permute");
    GetOptions ("l|language=s" => \@language);

    foreach (@language)
      {
	error "unknown language: $_"
	  unless exists $language{lc $_};
	unshift @ARGV, @{$language{lc $_}};
      }
  } while @language;

  # --debug is useless: it is parsed below.
  if (exists $ENV{'AUTOM4TE_DEBUG'})
    {
      print STDERR "$me: concrete arguments:\n";
      foreach my $arg (@ARGV)
	{
	  print STDERR "| $arg\n";
	}
    }

  # Process the arguments for real this time.
  my @trace;
  my @prepend_include;
  parse_WARNINGS;
  getopt
    (
     # Operation modes:
     "o|output=s"   => \$output,
     "W|warnings=s" => \&parse_warnings,
     "m|mode=s"     => \$mode,
     "M|melt"       => \$melt,

     # Library directories:
     "B|prepend-include=s" => \@prepend_include,
     "I|include=s"         => \@include,

     # Tracing:
     # Using a hash for traces is seducing.  Unfortunately, upon `-t FOO',
     # instead of mapping `FOO' to undef, Getopt maps it to `1', preventing
     # us from distinguishing `-t FOO' from `-t FOO=1'.  So let's do it
     # by hand.
     "t|trace=s"     => \@trace,
     "p|preselect=s" => \@preselect,

     # Freezing.
     "F|freeze" => \$freeze,

     # Caching.
     "C|cache=s" => \$cache,
     "no-cache"  => sub { $cache = undef; },
    );

  fatal "too few arguments
Try `$me --help' for more information."
    unless @ARGV;

  # Freezing:
  # We cannot trace at the same time (well, we can, but it sounds insane).
  # And it implies melting: there is risk not to update properly using
  # old frozen files, and worse yet: we could load a frozen file and
  # refreeze it!  A sort of caching :)
  fatal "cannot freeze and trace"
    if $freeze && @trace;
  $melt = 1
    if $freeze;

  # Names of the cache directory, cache directory index, trace cache
  # prefix, and output cache prefix.  If the cache is not to be
  # preserved, default to a temporary directory (automatically removed
  # on exit).
  $cache = $tmp
    unless $cache;
  $icache = "$cache/requests";
  $tcache = "$cache/traces.";
  $ocache = "$cache/output.";

  # Normalize the includes: the first occurrence is enough, several is
  # a pain since it introduces a useless difference in the path which
  # invalidates the cache.  And strip `.' which is implicit and always
  # first.
  @include = grep { !/^\.$/ } uniq (reverse(@prepend_include), @include);

  # Convert @trace to %trace, and work around the M4 builtins tracing
  # problem.
  # The default format is `$f:$l:$n:$%'.
  foreach (@trace)
    {
      /^([^:]+)(?::(.*))?$/ms;
      $trace{$1} = defined $2 ? $2 : '$f:$l:$n:$%';
      $trace{$m4_builtin_alternate_name{$1}} = $trace{$1}
	if exists $m4_builtin_alternate_name{$1};
    }

  # Work around the M4 builtins tracing problem for @PRESELECT.
  push (@preselect,
	map { $m4_builtin_alternate_name{$_} }
	grep { exists $m4_builtin_alternate_name{$_} } @preselect);

  # If we find frozen files, then all the files before it are
  # discarded: the frozen file is supposed to include them all.
  #
  # We don't want to depend upon m4's --include to find the top level
  # files, so we use `find_file' here.  Try to get a canonical name,
  # as it's part of the key for caching.  And some files are optional
  # (also handled by `find_file').
  my @argv;
  foreach (@ARGV)
    {
      if (/\.m4f$/)
	{
	  # Frozen files are optional => pass a `?' to `find_file'.
	  my $file = find_file ("$_?", @include);
	  if (!$melt && $file)
	    {
	      @argv = ($file);
	    }
	  else
	    {
	      s/\.m4f$/.m4/;
	      push @argv, find_file ($_, @include);
	    }
	}
      else
	{
	  my $file = find_file ($_, @include);
	  push @argv, $file
	    if $file;
	}
    }
  @ARGV = @argv;
}


# handle_m4 ($REQ, @MACRO)
# ------------------------
# Run m4 on the input files, and save the traces on the @MACRO.
sub handle_m4 ($@)
{
  my ($req, @macro) = @_;

  # GNU m4 appends when using --error-output.
  unlink ($tcache . $req->id . "t");

  # Run m4.
  #
  # Neutralize its stdin, so that GNU M4 1.5 doesn't neutralize SIGINT.
  #
  # We don't output directly to the cache files, to avoid problems
  # when we are interrupted (that leaves corrupted files).
  xsystem ("$m4"
	   . join (' --include=', '', @include)
	   . ' --debug=aflq'
	   . (!exists $ENV{'AUTOM4TE_NO_FATAL'} ? ' --fatal-warning' : '')
	   . " --error-output=$tcache" . $req->id . "t"
	   . join (' --trace=',   '', sort @macro)
	   . " " . files_to_options (@ARGV)
	   . ' </dev/null'
	   . " >$ocache" . $req->id . "t");

  # Everything went ok: preserve the outputs.
  foreach my $file (map { $_ . $req->id } ($tcache, $ocache))
    {
      use File::Copy;
      move ("${file}t", "$file")
	or fatal "cannot rename ${file}t as $file: $!";
    }
}


# warn_forbidden ($WHERE, $WORD, %FORBIDDEN)
# ------------------------------------------
# $WORD is forbidden.  Warn with a dedicated error message if in
# %FORBIDDEN, otherwise, a simple `error: possibly undefined macro'
# will do.
my $first_warn_forbidden = 1;
sub warn_forbidden ($$%)
{
  my ($where, $word, %forbidden) = @_;
  my $message;

  for my $re (sort keys %forbidden)
    {
      if ($word =~ $re)
	{
	  $message = $forbidden{$re};
	  last;
	}
    }
  $message ||= "possibly undefined macro: $word";
  warn "$where: error: $message\n";
  if ($first_warn_forbidden)
    {
      warn <<EOF;
      If this token and others are legitimate, please use m4_pattern_allow.
      See the Autoconf documentation.
EOF
      $first_warn_forbidden = 0;
    }
}


# handle_output ($REQ, $OUTPUT)
# -----------------------------
# Run m4 on the input files, perform quadrigraphs substitution, check for
# forbidden tokens, and save into $OUTPUT.
sub handle_output ($$)
{
  my ($req, $output) = @_;

  verb "creating $output";

  # Load the forbidden/allowed patterns.
  handle_traces ($req, "$tmp/patterns",
		 ('m4_pattern_forbid' => 'forbid:$1:$2',
		  'm4_pattern_allow'  => 'allow:$1'));
  my @patterns = new Autom4te::XFile ("$tmp/patterns")->getlines;
  chomp @patterns;
  my %forbidden =