Build files: Make it possible to source libraries into other libraries

Added functionality to use static libraries as source for other
libraries.  When done this way, the target library will use the object
files from the sourced static libraries, making the sourced libraries
work as "containers" for object files.

We also need to make sure that the Unix Makefile template knows how to
deal with shared libraries and modules that depend on static libraries.
That's new situation we haven't had before.

Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/10088)

4 files changed, 245 insertions, 70 deletions

diff --git a/Configurations/common.tmpl b/Configurations/common.tmpl
index 4999a36604..a2591da727 100644
--- a/Configurations/common.tmpl
+++ b/Configurations/common.tmpl
@@ -171,14 +171,30 @@
      my $bin = shift;
      my %opts = @_;
      if (@{$unified_info{sources}->{$obj}}) {
-         $OUT .= src2obj(obj => $obj,
-                         product => $bin,
-                         srcs => $unified_info{sources}->{$obj},
-                         deps => $unified_info{depends}->{$obj},
-                         incs => [ @{$unified_info{includes}->{$obj}},
-                                   @{$unified_info{includes}->{$bin}} ],
-                         defs => [ @{$unified_info{defines}->{$obj}},
-                                   @{$unified_info{defines}->{$bin}} ],
+         my @srcs = @{$unified_info{sources}->{$obj}};
+         my @deps = @{$unified_info{depends}->{$obj}};
+         my @incs = ( @{$unified_info{includes}->{$obj}},
+                      @{$unified_info{includes}->{$bin}} );
+         my @defs = ( @{$unified_info{defines}->{$obj}},
+                      @{$unified_info{defines}->{$bin}} );
+         print STDERR "DEBUG[doobj] \@srcs for $obj ($bin) : ",
+             join(",", map { "\n    $_" } @srcs), "\n"
+             if $debug_rules;
+         print STDERR "DEBUG[doobj] \@deps for $obj ($bin) : ",
+             join(",", map { "\n    $_" } @deps), "\n"
+             if $debug_rules;
+         print STDERR "DEBUG[doobj] \@incs for $obj ($bin) : ",
+             join(",", map { "\n    $_" } @incs), "\n"
+             if $debug_rules;
+         print STDERR "DEBUG[doobj] \@defs for $obj ($bin) : ",
+             join(",", map { "\n    $_" } @defs), "\n"
+             if $debug_rules;
+         print STDERR "DEBUG[doobj] \%opts for $obj ($bin) : ", ,
+             join(",", map { "\n    $_ = $opts{$_}" } sort keys %opts), "\n"
+             if $debug_rules;
+         $OUT .= src2obj(obj => $obj, product => $bin,
+                         srcs => [ @srcs ], deps => [ @deps ],
+                         incs => [ @incs ], defs => [ @defs ],
                          %opts);
          foreach ((@{$unified_info{sources}->{$obj}},
                    @{$unified_info{depends}->{$obj}})) {
@@ -188,37 +204,152 @@
      $cache{$obj} = 1;
  }
 
+ # Helper functions to grab all applicable intermediary files.
+ # This is particularly useful when a library is given as source
+ # rather than a dependency.  In that case, we consider it to be a
+ # container with object file references, or possibly references
+ # to further libraries to pilfer in the same way.
+ sub getsrclibs {
+     my $section = shift;
+
+     # For all input, see if it sources static libraries.  If it does,
+     # return them together with the result of a recursive call.
+     map { ( $_, getsrclibs($section, $_) ) }
+     grep { $_ =~ m|\.a$| }
+     map { @{$unified_info{$section}->{$_} // []} }
+     @_;
+ }
+
+ sub getlibobjs {
+     my $section = shift;
+
+     # For all input, see if it's an intermediary file (library or object).
+     # If it is, collect the result of a recursive call, or if that returns
+     # an empty list, the element itself.  Return the result.
+     map {
+         my @x = getlibobjs($section, @{$unified_info{$section}->{$_}});
+         @x ? @x : ( $_ );
+     }
+     grep { defined $unified_info{$section}->{$_} }
+     @_;
+ }
+
  # dolib is responsible for building libraries.  It will call
- # obj2shlib is shared libraries are produced, and obj2lib in all
+ # obj2shlib if 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};
+
+     my %attrs = %{$unified_info{attributes}->{libraries}->{$lib}};
+
+     my @deps = ( resolvedepends(getsrclibs('sources', $lib)) );
+
+     # We support two types of objs, those who are specific to this library
+     # (they end up in @objs) and those that we get indirectly, via other
+     # libraries (they end up in @foreign_objs).  We get the latter any time
+     # someone has done something like this in build.info:
+     #     SOURCE[libfoo.a]=libbar.a
+     # The indirect object files must be kept in a separate array so they
+     # don't get rebuilt unnecessarily (and with incorrect auxiliary
+     # information).
+     #
+     # Object files can't be collected commonly for shared and static
+     # libraries, because we contain their respective object files in
+     # {shared_sources} and {sources}, and because the implications are
+     # slightly different for each library form.
+     #
+     # We grab all these "foreign" object files recursively with getlibobjs().
+
      unless ($disabled{shared} || $lib =~ /\.a$/) {
          my $obj2shlib = defined &obj2shlib ? \&obj2shlib : \&libobj2shlib;
+         # If this library sources other static libraries and those
+         # libraries are marked {noinst}, there's no need to include
+         # all of their object files.  Instead, we treat those static
+         # libraries as dependents alongside any other library this
+         # one depends on, and let symbol resolution do its job.
+         my @sourced_libs = ();
+         my @objs = ();
+         my @foreign_objs = ();
+         my @deps = ();
+         foreach (@{$unified_info{shared_sources}->{$lib}}) {
+             if ($_ !~ m|\.a$|) {
+                 push @objs, $_;
+             } elsif ($unified_info{attributes}->{libraries}->{$_}->{noinst}) {
+                 push @deps, $_;
+             } else {
+                 push @deps, getsrclibs('sources', $_);
+                 push @foreign_objs, getlibobjs('sources', $_);
+             }
+         }
+         @deps = ( grep { $_ ne $lib } resolvedepends($lib, @deps) );
+         print STDERR "DEBUG[dolib:shlib] \%attrs for $lib : ", ,
+             join(",", map { "\n    $_ = $attrs{$_}" } sort keys %attrs), "\n"
+             if %attrs && $debug_rules;
+         print STDERR "DEBUG[dolib:shlib] \@deps for $lib : ",
+             join(",", map { "\n    $_" } @deps), "\n"
+             if @deps && $debug_rules;
+         print STDERR "DEBUG[dolib:shlib] \@objs for $lib : ",
+             join(",", map { "\n    $_" } @objs), "\n"
+             if @objs && $debug_rules;
+         print STDERR "DEBUG[dolib:shlib] \@foreign_objs for $lib : ",
+             join(",", map { "\n    $_" } @foreign_objs), "\n"
+             if @foreign_objs && $debug_rules;
          $OUT .= $obj2shlib->(lib => $lib,
-                              attrs => $unified_info{attributes}->{libraries}->{$lib},
-                              objs => $unified_info{shared_sources}->{$lib},
-                              deps => [ grep { $_ ne $lib } resolvedepends($lib) ]);
-         foreach ((@{$unified_info{shared_sources}->{$lib}},
-                   @{$unified_info{sources}->{$lib}})) {
+                              attrs => { %attrs },
+                              objs => [ @objs, @foreign_objs ],
+                              deps => [ @deps ]);
+         foreach (@objs) {
              # If this is somehow a compiled object, take care of it that way
              # Otherwise, it might simply be generated
              if (defined $unified_info{sources}->{$_}) {
-                 doobj($_, $lib, intent => "shlib",
-                       attrs => $unified_info{attributes}->{libraries}->{$lib});
+                 if($_ =~ /\.a$/) {
+                     dolib($_);
+                 } else {
+                     doobj($_, $lib, intent => "shlib", attrs => { %attrs });
+                 }
              } else {
                  dogenerate($_, undef, undef, intent => "lib");
              }
          }
      }
-     $OUT .= obj2lib(lib => $lib,
-                     attrs => $unified_info{attributes}->{libraries}->{$lib},
-                     objs => [ @{$unified_info{sources}->{$lib}} ]);
-     foreach (@{$unified_info{sources}->{$lib}}) {
-         doobj($_, $lib, intent => "lib",
-               attrs => $unified_info{attributes}->{libraries}->{$lib});
+     {
+         # When putting static libraries together, we cannot rely on any
+         # symbol resolution, so for all static libraries used as source for
+         # this one, as well as other libraries they depend on, we simply
+         # grab all their object files unconditionally,
+         # Symbol resolution will happen when any program, module or shared
+         # library is linked with this one.
+         my @objs = ();
+         my @sourcedeps = ();
+         my @foreign_objs = ();
+         foreach (@{$unified_info{sources}->{$lib}}) {
+             if ($_ !~ m|\.a$|) {
+                 push @objs, $_;
+             } else {
+                 push @sourcedeps, $_;
+             }
+         }
+         @sourcedeps = ( grep { $_ ne $lib } resolvedepends(@sourcedeps) );
+         print STDERR "DEBUG[dolib:lib] : \@sourcedeps for $_ : ",
+             join(",", map { "\n    $_" } @sourcedeps), "\n"
+             if @sourcedeps && $debug_rules;
+         @foreign_objs = getlibobjs('sources', @sourcedeps);
+         print STDERR "DEBUG[dolib:lib] \%attrs for $lib : ", ,
+             join(",", map { "\n    $_ = $attrs{$_}" } sort keys %attrs), "\n"
+             if %attrs && $debug_rules;
+         print STDERR "DEBUG[dolib:lib] \@objs for $lib : ",
+             join(",", map { "\n    $_" } @objs), "\n"
+             if @objs && $debug_rules;
+         print STDERR "DEBUG[dolib:lib] \@foreign_objs for $lib : ",
+             join(",", map { "\n    $_" } @foreign_objs), "\n"
+             if @foreign_objs && $debug_rules;
+         $OUT .= obj2lib(lib => $lib, attrs => { %attrs },
+                         objs => [ @objs, @foreign_objs ]);
+         foreach (@objs) {
+             doobj($_, $lib, intent => "lib", attrs => { %attrs });
+         }
      }
      $cache{$lib} = 1;
  }
@@ -229,17 +360,28 @@
  sub domodule {
      my $module = shift;
      return "" if $cache{$module};
+     my %attrs = %{$unified_info{attributes}->{modules}->{$module}};
+     my @objs = @{$unified_info{sources}->{$module}};
+     my @deps = ( grep { $_ ne $module }
+                  resolvedepends($module) );
+     print STDERR "DEBUG[domodule] \%attrs for $module :",
+         join(",", map { "\n    $_ = $attrs{$_}" } sort keys %attrs), "\n"
+         if $debug_rules;
+     print STDERR "DEBUG[domodule] \@objs for $module : ",
+         join(",", map { "\n    $_" } @objs), "\n"
+         if $debug_rules;
+     print STDERR "DEBUG[domodule] \@deps for $module : ",
+         join(",", map { "\n    $_" } @deps), "\n"
+         if $debug_rules;
      $OUT .= obj2dso(module => $module,
-                     attrs => $unified_info{attributes}->{modules}->{$module},
-                     objs => $unified_info{sources}->{$module},
-                     deps => [ grep { $_ ne $module }
-                               resolvedepends($module) ]);
+                     attrs => { %attrs },
+                     objs => [ @objs ],
+                     deps => [ @deps ]);
      foreach (@{$unified_info{sources}->{$module}}) {
          # If this is somehow a compiled object, take care of it that way
          # Otherwise, it might simply be generated
          if (defined $unified_info{sources}->{$_}) {
-             doobj($_, $module, intent => "dso",
-                   attrs => $unified_info{attributes}->{modules}->{$module});
+             doobj($_, $module, intent => "dso", attrs => { %attrs });
          } else {
              dogenerate($_, undef, $module, intent => "dso");
          }
@@ -252,13 +394,24 @@
  sub dobin {
      my $bin = shift;
      return "" if $cache{$bin};
+     my %attrs = %{$unified_info{attributes}->{programs}->{$bin}};
+     my @objs = @{$unified_info{sources}->{$bin}};
+     my @deps = ( grep { $_ ne $bin } resolvedepends($bin) );
+     print STDERR "DEBUG[dobin] \%attrs for $bin : ",
+         join(",", map { "\n    $_ = $attrs{$_}" } sort keys %attrs), "\n"
+         if %attrs && $debug_rules;
+     print STDERR "DEBUG[dobin] \@objs for $bin : ",
+         join(",", map { "\n    $_" } @objs), "\n"
+         if @objs && $debug_rules;
+     print STDERR "DEBUG[dobin] \@deps for $bin : ",
+         join(",", map { "\n    $_" } @deps), "\n"
+         if @deps && $debug_rules;
      $OUT .= obj2bin(bin => $bin,
-                     attrs => $unified_info{attributes}->{programs}->{$bin},
-                     objs => [ @{$unified_info{sources}->{$bin}} ],
-                     deps => [ grep { $_ ne $bin } resolvedepends($bin) ]);
-     foreach (@{$unified_info{sources}->{$bin}}) {
-         doobj($_, $bin, intent => "bin",
-               attrs => $unified_info{attributes}->{$bin});
+                     attrs => { %attrs },
+                     objs => [ @objs ],
+                     deps => [ @deps ]);
+     foreach (@objs) {
+         doobj($_, $bin, intent => "bin", attrs => { %attrs });
      }
      $cache{$bin} = 1;
  }
diff --git a/Configurations/platform/BASE.pm b/Configurations/platform/BASE.pm
index fcd7b70ccf..1ab4bf18e9 100644
--- a/Configurations/platform/BASE.pm
+++ b/Configurations/platform/BASE.pm
@@ -52,11 +52,13 @@ sub isdef       { return $_[1] =~ m|\.ld$|;   }
 sub isobj       { return $_[1] =~ m|\.o$|;    }
 sub isres       { return $_[1] =~ m|\.res$|;  }
 sub isasm       { return $_[1] =~ m|\.[Ss]$|; }
+sub isstaticlib { return $_[1] =~ m|\.a$|;    }
 sub convertext {
-    if ($_[0]->isdef($_[1]))    { return $_[0]->def($_[1]); }
-    if ($_[0]->isobj($_[1]))    { return $_[0]->obj($_[1]); }
-    if ($_[0]->isres($_[1]))    { return $_[0]->res($_[1]); }
-    if ($_[0]->isasm($_[1]))    { return $_[0]->asm($_[1]); }
+    if ($_[0]->isdef($_[1]))        { return $_[0]->def($_[1]); }
+    if ($_[0]->isobj($_[1]))        { return $_[0]->obj($_[1]); }
+    if ($_[0]->isres($_[1]))        { return $_[0]->res($_[1]); }
+    if ($_[0]->isasm($_[1]))        { return $_[0]->asm($_[1]); }
+    if ($_[0]->isstaticlib($_[1]))  { return $_[0]->staticlib($_[1]); }
     return $_[1];
 }
 
diff --git a/Configurations/platform/mingw.pm b/Configurations/platform/mingw.pm
index 5788a36e77..7dacb32a31 100644
--- a/Configurations/platform/mingw.pm
+++ b/Configurations/platform/mingw.pm
@@ -17,6 +17,9 @@ sub objext              { '.obj' }
 sub libext              { '.a' }
 sub dsoext              { '.dll' }
 sub defext              { '.def' }
+
+# Other extra that aren't defined in platform::BASE
+sub resext              { '.res.obj' }
 sub shlibext            { '.dll' }
 sub shlibextimport      { $target{shared_import_extension} || '.dll.a' }
 sub shlibextsimple      { undef }
diff --git a/Configurations/unix-Makefile.tmpl b/Configurations/unix-Makefile.tmpl
index 6de2acc9e7..7c44a04224 100644
--- a/Configurations/unix-Makefile.tmpl
+++ b/Configurations/unix-Makefile.tmpl
@@ -1015,7 +1015,7 @@ EOF
   # last in the line.  We may therefore need to put back a line ending.
   sub src2obj {
       my %args = @_;
-      my $obj = platform->obj($args{obj});
+      my $obj = platform->convertext($args{obj});
       my $dep = platform->dep($args{obj});
       my @srcs = @{$args{srcs}};
       my $srcs = join(" ",  @srcs);
@@ -1095,15 +1095,22 @@ EOF
   sub obj2shlib {
       my %args = @_;
       my @linkdirs = ();
-      foreach (@{args{deps}}) {
-          my $d = dirname($_);
-          push @linkdirs, $d unless grep { $d eq $_ } @linkdirs;
+      my @linklibs = ();
+      foreach (@{$args{deps}}) {
+          if (platform->isstaticlib($_)) {
+              push @linklibs, platform->convertext($_);
+          } else {
+              my $d = "-L" . dirname($_);
+              my $l = basename($_);
+              $l =~ s/^lib//;
+              $l = "-l" . $l;
+              push @linklibs, $l;
+              push @linkdirs, $d unless grep { $d eq $_ } @linkdirs;
+          }
       }
-      my $linkflags = join("", map { "-L$_ " } @linkdirs);
-      my $linklibs = join("", map { my $f = basename($_);
-                                    (my $l = $f) =~ s/^lib//;
-                                    " -l$l" } @{$args{deps}});
-      my @objs = map { platform->obj($_) }
+      my $linkflags = join("", map { $_." " } @linkdirs);
+      my $linklibs = join("", map { $_." " } @linklibs);
+      my @objs = map { platform->convertext($_) }
                  grep { !platform->isdef($_) }
                  @{$args{objs}};
       my @defs = map { platform->def($_) }
@@ -1158,15 +1165,23 @@ EOF
       my %args = @_;
       my $dso = platform->dso($args{module});
       my @linkdirs = ();
-      foreach (@{args{deps}}) {
-          my $d = dirname($_);
-          push @linkdirs, $d unless grep { $d eq $_ } @linkdirs;
+      my @linklibs = ();
+      foreach (@{$args{deps}}) {
+          next unless defined $_;
+          if (platform->isstaticlib($_)) {
+              push @linklibs, platform->convertext($_);
+          } else {
+              my $d = "-L" . dirname($_);
+              my $l = basename($_);
+              $l =~ s/^lib//;
+              $l = "-l" . $l;
+              push @linklibs, $l;
+              push @linkdirs, $d unless grep { $d eq $_ } @linkdirs;
+          }
       }
-      my $linkflags = join("", map { "-L$_ " } @linkdirs);
-      my $linklibs = join("", map { my $f = basename($_);
-                                    (my $l = $f) =~ s/^lib//;
-                                    " -l$l" } @{$args{deps}});
-      my @objs = map { platform->obj($_) }
+      my $linkflags = join("", map { $_." " } @linkdirs);
+      my $linklibs = join("", map { $_." " } @linklibs);
+      my @objs = map { platform->convertext($_) }
                  grep { !platform->isdef($_) }
                  @{$args{objs}};
       my @defs = map { platform->def($_) }
@@ -1180,7 +1195,7 @@ EOF
 $dso: $deps
 	\$(CC) \$(DSO_CFLAGS) $linkflags\$(DSO_LDFLAGS) \\
 		-o $dso$shared_def $objs \\
-                $linklibs \$(DSO_EX_LIBS)
+                $linklibs\$(DSO_EX_LIBS)
 EOF
   }
   sub obj2lib {
@@ -1200,20 +1215,22 @@ EOF
       my $objs = join(" ", map { platform->obj($_) } @{$args{objs}});
       my $deps = join(" ", compute_lib_depends(@{$args{deps}}));
       my @linkdirs = ();
-      foreach (@{args{deps}}) {
-          next if $_ =~ /\.a$/;
-          my $d = dirname($_);
-          push @linkdirs, $d unless grep { $d eq $_ } @linkdirs;
+      my @linklibs = ();
+      foreach (@{$args{deps}}) {
+          next unless defined $_;
+          if (platform->isstaticlib($_)) {
+              push @linklibs, platform->convertext($_);
+          } else {
+              my $d = "-L" . dirname($_);
+              my $l = basename($_);
+              $l =~ s/^lib//;
+              $l = "-l" . $l;
+              push @linklibs, $l;
+              push @linkdirs, $d unless grep { $d eq $_ } @linkdirs;
+          }
       }
-      my $linkflags = join("", map { "-L$_ " } @linkdirs);
-      my $linklibs = join("", map { if ($_ =~ m/\.a$/) {
-                                        " ".platform->staticlib($_);
-                                    } else {
-                                        my $f = basename($_);
-                                        (my $l = $f) =~ s/^lib//;
-                                        " -l$l"
-                                    }
-                                  } @{$args{deps}});
+      my $linkflags = join("", map { $_." " } @linkdirs);
+      my $linklibs = join("", map { $_." " } @linklibs);
       my $cmd = '$(CC)';
       my $cmdflags = '$(BIN_CFLAGS)';
       if (grep /_cc\.o$/, @{$args{objs}}) {
@@ -1225,7 +1242,7 @@ $bin: $objs $deps
 	rm -f $bin
 	\$\${LDCMD:-$cmd} $cmdflags $linkflags\$(BIN_LDFLAGS) \\
 		-o $bin $objs \\
-		$linklibs \$(BIN_EX_LIBS)
+		$linklibs\$(BIN_EX_LIBS)
 EOF
   }
   sub in2script {