FYI: autoscan

[Akim Demaille]

Index: ChangeLog
from  Akim Demaille  <address@hidden>
        
        * autoscan.in: Use IO::File.
        Adjust all the routines to use it.
        ($log): New file (autoscan.log).
        (output): Dump detailed logs into $log, and a shortened version to
        stderr.
        (&scan_makefile): Refine the regexp catching tokens in the code.
        * doc/autoconf.texi (autoscan Invocation): Document `autoscan.log'
        and the `configure.ac' checking feature.
        
Index: NEWS
--- NEWS Sun, 24 Jun 2001 10:00:42 +0200 akim (ace/31_NEWS 1.44.1.2 644)
+++ NEWS Thu, 12 Jul 2001 19:41:32 +0200 akim (ace/31_NEWS 1.44.1.2 644)
@@ -8,6 +8,7 @@
   other hard-to-quote constructs.
 - m4_pattern_forbid, m4_pattern_allow
 - Tips for upgrading from 2.13.
+- Using autoscan to maintain a configure.ac.
 
 ** Default includes
 - Now include stdint.h.
Index: autoscan.in
--- autoscan.in Sun, 01 Jul 2001 19:52:59 +0200 akim (ace/13_autoscan.p 1.41 
644)
+++ autoscan.in Thu, 12 Jul 2001 19:39:25 +0200 akim (ace/13_autoscan.p 1.41 
644)
@@ -24,6 +24,7 @@
 use File::Basename;
 use File::Find;
 use Getopt::Long;
+use IO::File;
 use strict;
 
 use vars qw(@cfiles @makefiles @shfiles %c_keywords %printed);
@@ -62,6 +63,8 @@
   );
 
 my $configure_scan = 'configure.scan';
+my $log = new IO::File ">$me.log"
+  or die "$me: cannot open $me.log: $!\n";
 
 # Autoconf and lib files.
 my $autoconf;
@@ -92,8 +95,9 @@ sub print_usage ()
 
 Examine source files in the directory tree rooted at SRCDIR, or the
 current directory if none is given.  Search the source files for
-common portability problems and create a file `$configure_scan' which
-is a preliminary `configure.ac' for that package.
+common portability problems, check for incompleteness of
+`configure.ac', and create a file `$configure_scan' which is a
+preliminary `configure.ac' for that package.
 
   -h, --help            print this help, then exit
   -V, --version         print version number, then exit
@@ -217,9 +221,9 @@ sub init_tables ()
   foreach my $kind (@kinds)
     {
       my $file = "$datadir/ac$kind";
-      open TABLE, $file or
-       die "$me: cannot open $file: $!\n";
-      while (<TABLE>)
+      my $table = new IO::File $file
+       or die "$me: cannot open $file: $!\n";
+      while ($_ = $table->getline)
        {
          # Ignore blank lines and comments.
          next
@@ -244,7 +248,8 @@ sub init_tables ()
              push @{$macro{$kind}{$word}}, $macro;
            }
        }
-      close(TABLE);
+      $table->close
+       or die "$me: cannot close $file: $!\n";
     }
 
   die "$me: some tables are inconsistent\n"
@@ -258,11 +263,11 @@ sub init_tables ()
 ## ----------------------- ##
 
 
-# scan_c_file(FILE)
-# -----------------
+# scan_c_file(FILENAME)
+# ---------------------
 sub scan_c_file ($)
 {
-  my ($file) = @_;
+  my ($filename) = @_;
 
   push (@cfiles, $File::Find::name);
   push (@{$used{'programs'}{"cc"}}, $File::Find::name);
@@ -270,8 +275,10 @@ sub scan_c_file ($)
   # Nonzero if in a multiline comment.
   my $in_comment = 0;
 
-  open(CFILE, "<$file") || die "$me: cannot open $file: $!\n";
-  while (<CFILE>)
+  my $file = new IO::File "<$filename"
+    or die "$me: cannot open $filename: $!\n";
+
+  while ($_ = $file->getline)
     {
       # Strip out comments, approximately.
       # Ending on this line.
@@ -315,19 +322,23 @@ sub scan_c_file ($)
            if !defined $c_keywords{$1};
        }
     }
-  close(CFILE);
+
+  $file->close
+    or die "$me: cannot close $filename: $!\n";
 }
 
 
-# scan_makefile(MAKEFILE)
-# -----------------------
+# scan_makefile(MAKEFILE-NAME)
+# ----------------------------
 sub scan_makefile ($)
 {
-  my ($file) = @_;
+  my ($filename) = @_;
   push (@makefiles, $File::Find::name);
 
-  open(MFILE, "<$file") || die "$me: cannot open $file: $!\n";
-  while (<MFILE>)
+  my $file = new IO::File "<$filename"
+    or die "$me: cannot open $filename: $!\n";
+
+  while ($_ = $file->getline)
     {
       # Strip out comments and variable references.
       s/#.*//;
@@ -346,24 +357,28 @@ sub scan_makefile ($)
          push (@{$used{'libraries'}{$1}}, "$File::Find::name:$.");
        }
       # Tokens in the code.
-      while (s/\b([a-zA-Z_]\w*)\b/ /)
+      while (s/(?<![-\w.])([a-zA-Z_]\w*)(?![-\w.])/ /)
        {
          push (@{$used{'programs'}{$1}}, "$File::Find::name:$.");
        }
     }
-  close(MFILE);
+
+  $file->close
+    or die "$me: cannot close $filename: $!\n";
 }
 
 
-# scan_sh_file(SHELL-SCRIPT)
-# --------------------------
+# scan_sh_file(SHELL-SCRIPT-NAME)
+# -------------------------------
 sub scan_sh_file ($)
 {
-  my ($file) = @_;
+  my ($filename) = @_;
   push (@shfiles, $File::Find::name);
 
-  open(MFILE, "<$file") || die "$me: cannot open $file: $!\n";
-  while (<MFILE>)
+  my $file = new IO::File "<$filename"
+    or die "$me: cannot open $filename: $!\n";
+
+  while ($_ = $file->getline)
     {
       # Strip out comments and variable references.
       s/#.*//;
@@ -376,7 +391,9 @@ sub scan_sh_file ($)
          push (@{$used{'programs'}{$1}}, "$File::Find::name:$.");
        }
     }
-  close(MFILE);
+
+  $file->close
+    or die "$me: cannot close $filename: $!\n";
 }
 
 
@@ -446,15 +463,15 @@ sub scan_files ()
 ## ----------------------- ##
 
 
-# output_kind ($KIND)
-# -------------------
-sub output_kind ($)
+# output_kind ($FILE, $KIND)
+# --------------------------
+sub output_kind ($$)
 {
-  my ($kind) = @_;
+  my ($file, $kind) = @_;
   # Lists of words to be checked with the generic macro.
   my @have;
 
-  print CONF "\n# $kind_comment{$kind}\n"
+  print $file "\n# $kind_comment{$kind}\n"
     if exists $kind_comment{$kind};
   foreach my $word (sort keys %{$used{$kind}})
     {
@@ -478,7 +495,7 @@ sub output_kind ($)
            {
              if (! $printed{$macro})
                {
-                 print CONF "$macro\n";
+                 print $file "$macro\n";
                  $printed{$macro} = 1;
                }
              push (@{$needed_macros{$macro}},
@@ -486,20 +503,22 @@ sub output_kind ($)
            }
        }
     }
-  print CONF "$generic_macro{$kind}([" . join(' ', sort(@have)) . "])\n"
+  print $file "$generic_macro{$kind}([" . join(' ', sort(@have)) . "])\n"
     if @have;
 }
 
 
-# output_libraries ()
-# -------------------
-sub output_libraries ()
+# output_libraries ($FILE)
+# ------------------------
+sub output_libraries ($)
 {
-  print CONF "\n# Checks for libraries.\n";
+  my ($file) = @_;
+
+  print $file "\n# Checks for libraries.\n";
   foreach my $word (sort keys %{$used{'libraries'}})
     {
-      print CONF "# FIXME: Replace `main' with a function in `-l$word':\n";
-      print CONF "AC_CHECK_LIB([$word], [main])\n";
+      print $file "# FIXME: Replace `main' with a function in `-l$word':\n";
+      print $file "AC_CHECK_LIB([$word], [main])\n";
     }
 }
 
@@ -512,23 +531,23 @@ sub output ($)
   my $configure_scan = shift;
   my %unique_makefiles;
 
-  open (CONF, ">$configure_scan") ||
-    die "$me: cannot create $configure_scan: $!\n";
+  my $file = new IO::File ">$configure_scan"
+    or die "$me: cannot create $configure_scan: $!\n";
 
-  print CONF "# Process this file with autoconf to produce a configure 
script.\n";
-  print CONF "AC_INIT\n";
+  print $file "# Process this file with autoconf to produce a configure 
script.\n";
+  print $file "AC_INIT(FULL-PACKAGE-NAME, VERSION, BUG-REPORT-ADDRESS)\n";
   if (defined $cfiles[0])
     {
-      print CONF "AC_CONFIG_SRCDIR([$cfiles[0]])\n";
-      print CONF "AC_CONFIG_HEADER([config.h])\n";
+      print $file "AC_CONFIG_SRCDIR([$cfiles[0]])\n";
+      print $file "AC_CONFIG_HEADER([config.h])\n";
     }
 
-  output_kind ('programs');
-  output_kind ('makevars');
-  output_libraries;
-  output_kind ('headers');
-  output_kind ('identifiers');
-  output_kind ('functions');
+  output_kind ($file, 'programs');
+  output_kind ($file, 'makevars');
+  output_libraries ($file);
+  output_kind ($file, 'headers');
+  output_kind ($file, 'identifiers');
+  output_kind ($file, 'functions');
 
   # Change DIR/Makefile.in to DIR/Makefile.
   foreach my $m (@makefiles)
@@ -536,12 +555,12 @@ sub output ($)
       $m =~ s/\.in$//;
       $unique_makefiles{$m}++;
     }
-  print CONF "\nAC_CONFIG_FILES([",
+  print $file "\nAC_CONFIG_FILES([",
        join ("\n                 ", sort keys %unique_makefiles), "])\n";
-  print CONF "AC_OUTPUT\n";
+  print $file "AC_OUTPUT\n";
 
-  close CONF ||
-    die "$me: closing $configure_scan: $!\n";
+  $file->close
+    or die "$me: cannot close $configure_scan: $!\n";
 }
 
 
@@ -557,19 +576,21 @@ sub output ($)
 # in CONFIGURE_AC.
 sub check_configure_ac ($)
 {
-  my ($configure_ac) = $@;
+  my ($configure_ac) = @_;
   my ($trace_option) = '';
 
+  # Find what needed macros are invoked in CONFIGURE_AC.
   foreach my $macro (sort keys %needed_macros)
     {
       $macro =~ s/\(.*//;
       $trace_option .= " -t $macro";
     }
 
-  open (TRACES, "$autoconf -A $datadir $trace_option $configure_ac|") ||
-    die "$me: cannot create read traces: $!\n";
+  my $traces =
+    new IO::File "$autoconf -A $datadir $trace_option $configure_ac|"
+      or die "$me: cannot create read traces: $!\n";
 
-  while (<TRACES>)
+  while ($_ = $traces->getline)
     {
       chomp;
       my ($file, $line, $macro, @args) = split (/:/, $_);
@@ -594,15 +615,19 @@ sub check_configure_ac ($)
        }
     }
 
-  close (TRACES) ||
-    die "$me: cannot close traces: $!\n";
+  $traces->close
+    or die "$me: cannot close: $!\n";
 
+  # Report the missing macros.
   foreach my $macro (sort keys %needed_macros)
     {
-      warn "$me: warning: missing $macro wanted by: \n";
+      warn ("$configure_ac: warning: missing $macro wanted by: "
+           . (${$needed_macros{$macro}}[0])
+           . "\n");
+      print $log "$me: warning: missing $macro wanted by: \n";
       foreach my $need (@{$needed_macros{$macro}})
         {
-          warn "\t$need\n";
+          print $log "\t$need\n";
         }
     }
 }
@@ -623,5 +648,8 @@ sub check_configure_ac ($)
   {
     check_configure_ac ($configure_ac);
   }
+
+$log->close
+  or die "$me: cannot close $me.log: $!\n";
 
 exit 0;
Index: doc/autoconf.texi
--- doc/autoconf.texi Sun, 01 Jul 2001 18:52:17 +0200 akim (ace/16_autoconf.t 
1.61.2.112.1.2 644)
+++ doc/autoconf.texi Thu, 12 Jul 2001 19:38:46 +0200 akim (ace/16_autoconf.t 
1.61.2.112.1.2 644)
@@ -985,24 +985,30 @@ @node autoscan Invocation, ifnames Invoc
 @section Using @code{autoscan} to Create @file{configure.ac}
 @cindex @code{autoscan}
 
-The @code{autoscan} program can help you create a @file{configure.ac}
-file for a software package.  @code{autoscan} examines source files in
-the directory tree rooted at a directory given as a command line
-argument, or the current directory if none is given.  It searches the
-source files for common portability problems and creates a file
address@hidden which is a preliminary @file{configure.ac} for
-that package.
+The @code{autoscan} program can help you create and/or maintain a
address@hidden file for a software package.  @code{autoscan}
+examines source files in the directory tree rooted at a directory given
+as a command line argument, or the current directory if none is given.
+It searches the source files for common portability problems and creates
+a file @file{configure.scan} which is a preliminary @file{configure.ac}
+for that package, and checks a possibly existing @file{configure.ac} for
+completeness.
 
-You should manually examine @file{configure.scan} before renaming it to
+When using @command{autoscan} to create a @file{configure.ac}, you
+should manually examine @file{configure.scan} before renaming it to
 @file{configure.ac}; it will probably need some adjustments.
-Occasionally, @code{autoscan} outputs a macro in the wrong order relative
-to another macro, so that @code{autoconf} produces a warning; you need
-to move such macros manually.  Also, if you want the package to use a
-configuration header file, you must add a call to
address@hidden (@pxref{Configuration Headers}).  You might also
-have to change or add some @code{#if} directives to your program in
+Occasionally, @code{autoscan} outputs a macro in the wrong order
+relative to another macro, so that @code{autoconf} produces a warning;
+you need to move such macros manually.  Also, if you want the package to
+use a configuration header file, you must add a call to
address@hidden (@pxref{Configuration Headers}).  You might
+also have to change or add some @code{#if} directives to your program in
 order to make it work with Autoconf (@pxref{ifnames Invocation}, for
 information about a program that can help with that job).
+
+When using @command{autoscan} to maintain a @file{configure.ac}, simply
+consider adding its suggestions.  The file @file{autoscan.log} will
+contain detailed information on why a macro is requested.
 
 @code{autoscan} uses several data files (installed along with Autoconf)
 to determine which macros to output when it finds particular symbols in