{- # -*- Mode: perl -*-

     # A cache of objects for which a recipe has already been generated
     my %cache;

 # resolvedepends and reducedepends work in tandem to make sure
 # there are no duplicate dependencies and that they are in the
 # right order.  This is especially used to sort the list of
 # libraries that a build depends on.
 sub resolvedepends {
     my $thing = shift;
     my @listsofar = @_;    # to check if we're looping
     my @list = @{$unified_info{depends}->{$thing}};
     my @newlist = ();
     if (scalar @list) {
         foreach my $item (@list) {
             # It's time to break off when the dependency list starts looping
             next if grep { $_ eq $item } @listsofar;
             push @newlist, $item, resolvedepends($item, @listsofar, $item);
         }
     }
     @newlist;
 }
 sub reducedepends {
     my @list = @_;
     my @newlist = ();
     while (@list) {
         my $item = shift @list;
         push @newlist, $item
             unless grep { $item eq $_ } @list;
     }
     @newlist;
 }

 # dogenerate is responsible for producing all the recipes that build
 # generated source files.  It recurses in case a dependency is also a
 # generated source file.
 sub dogenerate {
     my $src = shift;
     return "" if $cache{$src};
     my $obj = shift;
     my $bin = shift;
     my %opts = @_;
     if ($unified_info{generate}->{$src}) {
         $OUT .= generatesrc(src => $src,
                             generator => $unified_info{generate}->{$src},
                             deps => $unified_info{depends}->{$src},
                             incs => [ @{$unified_info{includes}->{$bin}},
                                       @{$unified_info{includes}->{$obj}} ],
                             %opts);
         foreach (@{$unified_info{depends}->{$src}}) {
             dogenerate($_, $obj, $bin, %opts);
         }
     }
     $cache{$src} = 1;
 }

 # doobj is responsible for producing all the recipes that build
 # object files as well as dependency files.
 sub doobj {
     my $obj = shift;
     return "" if $cache{$obj};
     (my $obj_no_o = $obj) =~ s|\.o$||;
     my $bin = shift;
     my %opts = @_;
     if (@{$unified_info{sources}->{$obj}}) {
         $OUT .= src2obj(obj => $obj_no_o,
                         srcs => $unified_info{sources}->{$obj},
                         deps => $unified_info{depends}->{$obj},
                         incs => [ @{$unified_info{includes}->{$bin}},
                                   @{$unified_info{includes}->{$obj}} ],
                         %opts);
         foreach ((@{$unified_info{sources}->{$obj}},
                   @{$unified_info{depends}->{$obj}})) {
             dogenerate($_, $obj, $bin, %opts);
         }
     }
     $cache{$obj} = 1;
 }

 # dolib is responsible for building libraries.  It will call
 # libobj2shlib is shared libraries are produced, and obj2lib in all
 # cases.  It also makes sure all object files for the library are
 # built.
 sub dolib {
     my $lib = shift;
     return "" if $cache{$lib};
     unless ($disabled{shared}) {
         my %ordinals =
             $unified_info{ordinals}->{$lib}
             ? (ordinals => $unified_info{ordinals}->{$lib}) : ();
         $OUT .= libobj2shlib(shlib => $unified_info{sharednames}->{$lib},
                              lib => $lib,
                              objs => [ map { (my $x = $_) =~ s|\.o$||; $x }
                                        @{$unified_info{sources}->{$lib}} ],
                              deps => [ reducedepends(resolvedepends($lib)) ],
                              %ordinals);
     }
     $OUT .= obj2lib(lib => $lib,
                     objs => [ map { (my $x = $_) =~ s|\.o$||; $x }
                               @{$unified_info{sources}->{$lib}} ]);
     map { doobj($_, $lib, intent => "lib") } @{$unified_info{sources}->{$lib}};
     $cache{$lib} = 1;
 }

 # doengine is responsible for building engines.  It will call
 # obj2dso, and also makes sure all object files for the library
 # are built.
 sub doengine {
     my $lib = shift;
     return "" if $cache{$lib};
     $OUT .= obj2dso(lib => $lib,
                     objs => [ map { (my $x = $_) =~ s|\.o$||; $x }
                               @{$unified_info{sources}->{$lib}} ],
                     deps => [ resolvedepends($lib) ]);
     map { doobj($_, $lib, intent => "dso") } @{$unified_info{sources}->{$lib}};
     $cache{$lib} = 1;
 }

 # dobin is responsible for building programs.  It will call obj2bin,
 # and also makes sure all object files for the library are built.
 sub dobin {
     my $bin = shift;
     return "" if $cache{$bin};
     my $deps = [ reducedepends(resolvedepends($bin)) ];
     $OUT .= obj2bin(bin => $bin,
                     objs => [ map { (my $x = $_) =~ s|\.o$||; $x }
                               @{$unified_info{sources}->{$bin}} ],
                     deps => $deps);
     map { doobj($_, $bin, intent => "bin") } @{$unified_info{sources}->{$bin}};
     $cache{$bin} = 1;
 }

 # dobin is responsible for building scripts from templates.  It will
 # call in2script.
 sub doscript {
     my $script = shift;
     return "" if $cache{$script};
     $OUT .= in2script(script => $script,
                       sources => $unified_info{sources}->{$script});
     $cache{$script} = 1;
 }

 # Start with populating the cache with all the overrides
 %cache = map { $_ => 1 } @{$unified_info{overrides}};

 # Build all known libraries, engines, programs and scripts.
 # Everything else will be handled as a consequence.
 map { dolib($_) } @{$unified_info{libraries}};
 map { doengine($_) } @{$unified_info{engines}};
 map { dobin($_) } @{$unified_info{programs}};
 map { doscript($_) } @{$unified_info{scripts}};

 # Finally, should there be any applicable BEGINRAW/ENDRAW sections,
 # they are added here.
 $OUT .= $_."\n" foreach(@{$unified_info{rawlines}});
-}