#!/usr/bin/perl
#-----------------------------------------------------------------------
#              mkmf: Perl script for makefile construction
#
# AUTHOR: V. Balaji (v.balaji@noaa.gov)
#         Princeton University/GFDL
#
# Full web documentation for mkmf:
#     http://www.gfdl.noaa.gov/~vb/mkmf.html
#
# 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 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.
#
# For the full text of the GNU General Public License,
# write to: Free Software Foundation, Inc.,
#           675 Mass Ave, Cambridge, MA 02139, USA.
#-----------------------------------------------------------------------

$ENV{'LANG'} = 'C';
require 5;
use strict;
use File::Basename;
use Getopt::Std;
use Config;			# use to put in platform-specific stuff
use vars qw( $opt_a $opt_c $opt_d $opt_f $opt_l $opt_m $opt_o $opt_p $opt_t $opt_v $opt_x ); # declare these global to be shared with Getopt:Std

#subroutines
sub ensureTrailingSlash {
#ensure trailing slash on directory names
   local $/ = '/'; chomp @_[0]; @_[0] .= '/';
}

my $version = '$Id: mkmf,v 14.0 2007/03/20 22:13:27 fms Exp $ ';

# initialize variables: use getopts for these
getopts( 'a:c:dfm:o:p:t:vx' ) || die "\aSyntax: $0 [-a abspath] [-c cppdefs] [-d] [-f] [-m makefile] [-o otherflags] ][-p program] [-t template] [-v] [-x] [targets]\n";
$opt_v = 1 if $opt_d;	# debug flag turns on verbose flag also
print "$0 $version\n" if $opt_v;

my $mkfile = $opt_m || 'Makefile';
print "Making makefile $mkfile ...\n" if $opt_v;

$opt_p = 'a.out' unless $opt_p;	# set default program name
my @targets = '.';		# current working directory is always included in targets
push @targets, @ARGV;		# then add remaining arguments on command line

ensureTrailingSlash($opt_a) if $opt_a;

#some generic declarations
my( $file, $include, $line, $module, $name, $object, $path, $source, $suffix, $target, $word );
my @list;
#some constants
my $endline = $/;
my @src_suffixes = ( q/\.F/, q/\.F90/, q/\.c/, q/\.f/, q/\.f90/ );
my @inc_suffixes = ( q/\.H/, q/\.fh/, q/\.h/, q/\.inc/, q/\.h90/ );
# push @inc_suffixes, @src_suffixes; # sourcefiles can be includefiles too: DISALLOW, 6 May 2004
# suffixes for the target (mkmf -p): if isn't on the list below it's a program
my @tgt_suffixes = ( q/\.a/ );

my %compile_cmd = (			# command to create .o file from a given source file suffix
      q/.F/   => q/$(FC) $(CPPDEFS) $(CPPFLAGS) $(FFLAGS) $(OTHERFLAGS) -c/,
      q/.F90/ => q/$(FC) $(CPPDEFS) $(CPPFLAGS) $(FFLAGS) $(OTHERFLAGS) -c/,
      q/.c/   => q/$(CC) $(CPPDEFS) $(CPPFLAGS) $(CFLAGS) $(OTHERFLAGS) -c/,
      q/.f/   => q/$(FC) $(FFLAGS) $(OTHERFLAGS) -c/,
      q/.f90/ => q/$(FC) $(FFLAGS) $(OTHERFLAGS) -c/              );
my %delim_match = ( q/'/ => q/'/,	# hash to find includefile delimiter pair
		    q/"/ => q/"/,
		    q/</ => q/>/ );

#formatting command for MAKEFILE, keeps very long lines to 256 characters
format MAKEFILE =
^<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< \~
$line
.

sub print_formatted_list{
#this routine, in conjunction with the format line above, can be used to break up long lines
# it is currently used to break up the potentially long defs of SRC, OBJ, CPPDEFS, etc.
# not used for the dependency lists
   $line = "@_";
   local $: = " \t\n";		# the default formatting word boundary includes the hyphen, but not here
   while ( $opt_f && length $line > 254 ) {
      write MAKEFILE, $line;
   }
   print MAKEFILE $line unless $line eq '';
   print MAKEFILE "\n";
}

#begin writing makefile
open MAKEFILE, ">$mkfile" or die "\aERROR opening file $mkfile for writing: $!\n";
printf MAKEFILE "# Makefile created by %s $version\n\n", basename($0);
print  MAKEFILE "include $opt_t\n\n" if $opt_t; #include template if supplied
print  MAKEFILE "SRCROOT = $opt_a\n\n" if $opt_a; # make abspath a variable
if ( $opt_c ) {
   if ( $Config{osname} eq 'aix' ) {
      $opt_c .= ' -D__aix';
#AIX fortran (xlf) requires -WF, in front, comma delimiter, no spaces
      my $cppdefs_xlf = '-WF "' . $opt_c . '"';
      $cppdefs_xlf =~ s/,/\\,/g; # escape any commas already there
      $cppdefs_xlf =~ s/\s+/,/g; # replace whitespace with commas
      &print_formatted_list("CPPDEFS_XLF = $cppdefs_xlf");
      $compile_cmd{'.F'}   = q/$(FC) $(CPPDEFS_XLF) $(FFLAGS) -c/;
      $compile_cmd{'.F90'} = q/$(FC) $(CPPDEFS_XLF) $(FFLAGS) -c/;
   }
   &print_formatted_list("CPPDEFS = $opt_c") if $opt_c;
}
print MAKEFILE "\nOTHERFLAGS = $opt_o" if $opt_o;
print MAKEFILE "\n.DEFAULT:\n\t-touch \$@\n";
print MAKEFILE "all: $opt_p\n"; # first target should be program, so you can type just 'make'

#if cppdefs flag is present, look for changes in cppdefs
my %chgdefs;
if ( $opt_c ) {
#split argument of -c into newdefs
   my %newdefs;
   foreach ( split /\s*-D/, $opt_c ) {
      $newdefs{$_} = 1;
   }
#get olddefs from file .cppdefs
   my %olddefs;
   my $cppdefsfile = '.cppdefs';
   if ( -f $cppdefsfile ) {
      open CPPFILE, $cppdefsfile or die "\aERROR opening cppdefsfile $cppdefsfile: $!\n";
      while ( <CPPFILE> ) {
	 foreach $word ( split ) {
	    $olddefs{$word} = 1;
	 }
      }
      close CPPFILE;
#get words that are not in both newdefs and olddefs
#if you move this foreach{} outside the enclosing if{} then
#   all cppdefs will be considered changed if there is no .cppdefs file.
      foreach ( keys %newdefs, keys %olddefs ) {
	 $chgdefs{$_} = 1 unless( $newdefs{$_} && $olddefs{$_} );
      }
   }
#write current cppdefs list to file .cppdefs
   open  CPPFILE, ">$cppdefsfile";
   my @newdefs = keys %newdefs;
   print CPPFILE " @newdefs\n";
   close CPPFILE;
   if( $opt_d ) {
      @list = keys %newdefs; print "newdefs= @list\n";
      @list = keys %olddefs; print "olddefs= @list\n";
      @list = keys %chgdefs; print "chgdefs= @list\n";
   }
}
delete $chgdefs{''};

# get a list of sourcefiles to be treated from targets
# (a sourcefile is any regular file with a suffix matching src_suffixes)
# if target is a sourcefile, add to list
# if target is a directory, get all sourcefiles there
# if target is a regular file that is not a sourcefile, look for a
#    sourcefile on last work of each line, rest of line (if present) is the
#    compile command to apply to this file.
#@sources will contain a unique list of sourcefiles in targets
#@objects will contain corresponding objects

#separate targets into directories and files
my %scanned;			# list of directories/files already scanned
my %actual_source_of;		# hash returning sourcefile from object
my %source_of; # sourcefile from object, using SRCROOT variable if present
my @includepaths;
my $scanOrder = 0;              # used to remember order of directory scan
foreach $target ( @targets ) {
   print STDERR '.' unless $opt_v; # show progress on screen (STDERR is used because it is unbuffered)
   if ( $opt_a and substr($target,0,1) ne '/' ) {
      # if an abs_path exists, attach it to all relative paths
      $target = $opt_a . $target;
   }
   ensureTrailingSlash($target) if( -d $target );
   print "target=$target\n" if $opt_v;
#directory
   if ( -d $target && !$scanned{$target} ) {
      print "Processing directory $target\n" if $opt_v;
      opendir DIR, $target;
      my @files = readdir DIR;
#find all sourcefiles in directory DIR
      foreach ( @files ) {
	 ( $name, $path, $suffix ) = fileparse( "$target$_", @inc_suffixes );
         push @includepaths, $target if $suffix; # is this line doing anything? looks like includepaths='' later...
	 ( $name, $path, $suffix ) = fileparse( "$target$_", @src_suffixes );
	 $object = "$name.o";
	 if( $suffix && !$actual_source_of{$object} ) {
	    if ( $opt_a and substr($path,0,1) ne '/' ) { # if an abs_path exists, attach it to all relative paths
	       ensureTrailingSlash($path);
               $path = '' if $path eq './';
               $source_of{$object} = '$(SRCROOT)' . "$path$name$suffix";
	       $path = $opt_a . $path;
	    }
            $actual_source_of{$object} = "$path$name$suffix";
            $source_of{$object} = $actual_source_of{$object} unless $source_of{$object};
         }
      }
      closedir DIR;
      $scanned{$target} = $scanOrder++;
   } elsif ( -f $target ) {
#file: check if it is a sourcefile
      ( $name, $path, $suffix ) = fileparse( $target, @src_suffixes );
      $object = "$name.o";
      if ( !$actual_source_of{$object} ) {
	 if ( $suffix ) {
	    $path = '' if $path eq './';
	    if ( $opt_a and substr($path,0,1) ne '/' ) { # if an abs_path exists, attach it to all relative paths
	       ensureTrailingSlash($path);
               $source_of{$object} = '$(SRCROOT)' . "$path$name$suffix";
	       $path = $opt_a . $path;
	    }
	    $actual_source_of{$object} = "$path$name$suffix";
            $source_of{$object} = $actual_source_of{$object} unless $source_of{$object};
	 } else {
            ( $name, $path, $suffix ) = fileparse( $target, @inc_suffixes );
            if ( ! $suffix ) {
#not a sourcefile: assume it contains list of sourcefiles
#specify files requiring special commands (e.g special compiler flags) thus:
#   f90 -Oaggress a.f90
#if last word on line is not a valid sourcefile, line is ignored
               open CMDFILE, $target;
               print "Reading commands from $target...\n" if $opt_v;
               while ( <CMDFILE> ) {
                  next if ( $_ eq "\n");
                  $line = $_;
                  my @wordlist = split;
                  $file = @wordlist[$#wordlist]; # last word on line
                  ( $name, $path, $suffix ) = fileparse( $file, @src_suffixes );
                  print "file=$file suffix=$suffix in $target\n" if $opt_d;
                  $object = "$name.o";
                  if ( $suffix && !$actual_source_of{$object} ) {
                     $path = '' if $path eq './';
                     if ( $opt_a and ( substr($path,0,1) ne '/' ) ) { # if an abs_path exists, attach it to all relative paths
                        ensureTrailingSlash($path);
                        $source_of{$object} = '$(SRCROOT)' . "$path$name$suffix";
                        $path = $opt_a . $path;
                     }
                     $actual_source_of{$object} = "$path$name$suffix";
                     $source_of{$object} = $actual_source_of{$object} unless $source_of{$object};
                     $scanned{$path} = $scanOrder++ unless $scanned{$path};
#command for this file is all of line except the filename
                     $line =~ /\s+$file/; $line=$`;
                     if ( $line ) {
                        $compile_cmd{"$name$suffix"} = $line;
                        print "Special command for file $name$suffix: ($line)\n" if $opt_v;
                     }
                  }
                  if ( ! $suffix ) { # look for include files
                     ( $name, $path, $suffix ) = fileparse( $file, @inc_suffixes );
                     if ( $opt_a and ( substr($path,0,1) ne '/' ) ) { # if an abs_path exists, attach it to all relative paths
                        ensureTrailingSlash($path);
                        $path = $opt_a . $path;
                     }
                     print "file=$file path=$path suffix=$suffix order=$scanOrder in $target\n" if $opt_d;
# anything that's found here is an includefile but not a sourcefile...
# just include directory in scan
                     $scanned{$path} = $scanOrder++
                       if ( $suffix && !$scanned{$path} );
                  }
               }
               close CMDFILE;
            }
	 }
      }
   }
}
delete $actual_source_of{''};
# sort scanned directories by scan order
sub ascendingScanOrder { $scanned{$a} <=> $scanned{$b}; }
my @dirs = sort ascendingScanOrder keys %scanned;
my @sources = values %source_of;
my @objects = keys   %source_of;
if( $opt_d ) {
   print "DEBUG: dirs= @dirs\n";
   print "DEBUG: sources= @sources\n";
   print "DEBUG: objects= @objects\n";
}

my %obj_of_module;		# hash returning name of object file containing module
my %modules_used_by;		# hash of modules used by a given source file (hashed against the corresponding object)
my %includes_in;		# hash of includes in a given source file (hashed against the corresponding object)
my %has_chgdefs;		# hash of files contains cppdefs that have been changed
#subroutine to scan file for use and module statements, and include files
# first argument is $object, second is $file
sub scanfile_for_keywords {
   my $object = shift;
   my $file = shift;
   local $/ = $endline;
#if file has already been scanned, return: but first check if any .o needs to be removed
   if( $scanned{$file} ) {
       if( $has_chgdefs{$file} and -f $object ) {
	   unlink $object or die "\aERROR unlinking $object: $!\n";
	   print "   Object $object is out-of-date because of change to cppdefs, removed.\n" if $opt_v;
       }
       return;
   }
   print "Scanning file $file of object $object ...\n" if $opt_v;
   open FILE, $file or die "\aERROR opening file $file of object $object: $!\n";
   foreach $line ( <FILE> ) {
      if ( $line =~ /^\s*module\s+(\w*)/ix ) {
	 if ( $1 ) {
	    my $module = lc $1;
	    if ( $obj_of_module{$module} && $module ne "procedure" ) {
	       die "\a\nAMBIGUOUS: Module $module is associated with $file as well as $actual_source_of{$obj_of_module{$module}}.\n";
	    }
	    $obj_of_module{$module} = $object;
	 }
      }
      if ( $line =~ /^\s*use\s*(\w*)/ix ) {
	 $modules_used_by{$object} .= ' ' . lc $1 if $1;
      }
      if ( $line =~ /^[\#\s]*include\s*(['""'<])([\w\.\/]*)$delim_match{\1}/ix ) {
	 $includes_in{$file} .= ' ' . $2 if $2;
      }
      foreach ( keys %chgdefs ) {
	 $_ .= '='; /\s*=/; $word=$`; #cut string at =sign, else whole string
	 if ( $line =~ /\b$word\b/ ) {
	    $has_chgdefs{$file} = 1;
	    if ( -f $object ) {
	       unlink $object or die "\aERROR unlinking $object: $!\n";
	       print "   Object $object is out-of-date because of change to cppdef $word, removed.\n" if $opt_v;
	    }
	 }
      }
   }
   close FILE;
   $scanned{$file} = 1;
   print "   uses modules=$modules_used_by{$object}, and includes=$includes_in{$file}.\n" if $opt_d;
}

foreach $object ( @objects ) {
   &scanfile_for_keywords( $object, $actual_source_of{$object} );
}

my %off_sources;		# list of source files not in current directory
my %includes;			# global list of includes
my %used;			# list of object files that are used by others
my @cmdline;
# for each file in sources, write down dependencies on includes and modules
foreach $object ( sort @objects ) {
   print STDERR '.' unless $opt_v; # show progress on screen (STDERR is used because it is unbuffered)
   my %is_used;			# hash of objects containing modules used by current object
   my %obj_of_include;		# hash of includes for current object
   $is_used{$object} = 1;	# initialize with current object so as to avoid recursion
   print "Collecting dependencies for $object ...\n" if $opt_v;
   @cmdline = "$object: $source_of{$object}";
   ( $name, $path, $suffix ) = fileparse( $actual_source_of{$object}, @src_suffixes );
   $off_sources{$source_of{$object}} = 1 unless( $path eq './' or $path eq '' );
#includes: done in subroutine since it must be recursively called to look for embedded includes
   @includepaths = '';
   &get_include_list( $object, $actual_source_of{$object} );
#modules
   foreach $module ( split /\s+/, $modules_used_by{$object} ) {
      $target = $obj_of_module{$module};
#we need to check target ne '' also below, since it is not mkmf's privilege
#to complain about modules not found. That should be left to the compiler.
      if( $target and !$is_used{$target} ) {
	 $is_used{$target} = 1;
	 push @cmdline, $target;
	 $used{$target} = 1;
	 print "   found module $module in object $target ...\n" if $opt_v;
      }
   }
#write the command line: if no file-specific command, use generic command for this suffix
   &print_formatted_list(@cmdline);
   $file = $actual_source_of{$object};
   if ( $compile_cmd{$name.$suffix} ) {
      print MAKEFILE "\t$compile_cmd{$name.$suffix}";
   } else {
      print MAKEFILE "\t$compile_cmd{$suffix}";
   }
   foreach ( @includepaths ) { # include files may be anywhere in directory array
      print MAKEFILE " -I$_" if $_;
   }
   print MAKEFILE "\t$source_of{$object}\n";

# subroutine to seek out includes recursively
   sub get_include_list {
      my( $incfile, $incname, $incpath, $incsuffix );
      my @paths;
      my $object = shift;
      my $file = shift;
      foreach ( split /\s+/, $includes_in{$file} ) {
	 print "object=$object, file=$file, include=$_.\n" if $opt_d;
	 ( $incname, $incpath, $incsuffix ) = fileparse( $_, @inc_suffixes );
	 if( $incsuffix ) {	# only check for files with proper suffix
	    undef $incpath if $incpath eq './';
	    if( $incpath =~ /^\// ) {
	       @paths = $incpath; # exact incpath specified, use it
	    } else {
	       @paths = @dirs;
	    }
	    foreach ( @paths ) {
	       local $/ = '/'; chomp; # remove trailing / if present
	       my $newincpath = "$_/$incpath" if $_;
	       undef $newincpath if $newincpath eq './';
	       $incfile = "$newincpath$incname$incsuffix";
               if ( $opt_a and ( substr($newincpath,0,1) ne '/' ) ) {
                  $newincpath = '$(SRCROOT)' . $newincpath;
               }
	       print "DEBUG: checking for $incfile in $_ ...\n" if $opt_d;
	       if ( -f $incfile and $obj_of_include{$incfile} ne $object ) {
		  print "   found $incfile ...\n" if $opt_v;
		  push @cmdline, "$newincpath$incname$incsuffix";
		  $includes{$incfile} = 1;
		  chomp( $newincpath, $path );
		  $off_sources{$incfile} = 1 if $newincpath;
		  $newincpath = '.' if $newincpath eq '';
		  push @includepaths, $newincpath unless( grep $_ eq $newincpath, @includepaths );
		  &scanfile_for_keywords($object,$incfile);
		  $obj_of_include{$incfile} = $object;
		  &get_include_list($object,$incfile); # recursively look for includes
		  last;
	       }
	    }
	 }
      }
   }
}

#lines to facilitate creation of local copies of source from other directories
#commented out because it makes make default rules kick in
foreach ( keys %off_sources ) {
   my $file = basename($_);
   $file =~ s/\$\(SRCROOT\)//;
   print MAKEFILE "./$file: $_\n\tcp $_ .\n";
}

#objects not used by other objects
#if every object is a module, then only the unused objects
#need to be passed to the linker (see commented OBJ = line below).
#if any f77 or C routines are present, we need complete list
my @unused_objects;
foreach $object ( @objects ) {
   push @unused_objects, $object unless $used{$object};
}

&print_formatted_list( "SRC =", @sources, keys %includes );
&print_formatted_list( "OBJ =", @objects );
# &print_formatted_list( "OBJ =", @unused_objects );
my $noff = scalar keys %off_sources;
&print_formatted_list( "OFF =", keys %off_sources ) if $noff > 0;

#write targets
print MAKEFILE "clean: neat\n\t-rm -f .cppdefs \$(OBJ) $opt_p\n";
print MAKEFILE "neat:\n\t-rm -f \$(TMPFILES)\n";
print MAKEFILE "localize: \$(OFF)\n\tcp \$(OFF) .\n" if $noff > 0;
print MAKEFILE "TAGS: \$(SRC)\n\tetags \$(SRC)\n";
print MAKEFILE "tags: \$(SRC)\n\tctags \$(SRC)\n";
( $name, $path, $suffix ) = fileparse( $opt_p, @tgt_suffixes );
if( $suffix eq '.a' ) {
   print MAKEFILE "$opt_p: \$(OBJ)\n\t\$(AR) \$(ARFLAGS) $opt_p \$(OBJ)\n";
} else {
# opt_l is a new flag added to take care of libraries
   print MAKEFILE "$opt_p: \$(OBJ) $opt_l\n\t\$(LD) \$(OBJ) -o $opt_p $opt_l \$(LDFLAGS)\n";
}
close MAKEFILE;
print " $mkfile is ready.\n";

exec 'make', '-f', $mkfile if $opt_x;
