Building: make it possible to force linking with static OpenSSL libs

Very simply, support having the .a extension to denote depending on
static libraries.  Note that this is not supported on native Windows
when building shared libraries, as there is not static library then,
just an import library with the same name.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/1889)

Configurations/common.tmpl

@@ -9,15 +9,22 @@
  # 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 extensionlesslib {
+     my @result = map { $_ =~ /(\.a)?$/; $` } @_;
+     return @result if wantarray;
+     return $result[0];
+ }
  sub resolvedepends {
      my $thing = shift;
+     my $extensionlessthing = extensionlesslib($thing);
      my @listsofar = @_;    # to check if we're looping
-     my @list = @{$unified_info{depends}->{$thing}};
+     my @list = @{$unified_info{depends}->{$extensionlessthing}};
      my @newlist = ();
      if (scalar @list) {
          foreach my $item (@list) {
+             my $extensionlessitem = extensionlesslib($item);
              # It's time to break off when the dependency list starts looping
-             next if grep { $_ eq $item } @listsofar;
+             next if grep { extensionlesslib($_) eq $extensionlessitem } @listsofar;
              push @newlist, $item, resolvedepends($item, @listsofar, $item);
          }
      }
@@ -28,8 +35,9 @@
      my @newlist = ();
      while (@list) {
          my $item = shift @list;
+         my $extensionlessitem = extensionlesslib($item);
          push @newlist, $item
-             unless grep { $item eq $_ } @list;
+             unless grep { $extensionlessitem eq extensionlesslib($_) } @list;
      }
      @newlist;
  }

Configurations/descrip.mms.tmpl

@@ -525,6 +525,17 @@ configdata.pm : $(SRCDIR)Configure $(SRCDIR)config.com {- join(" ", @{$config{bu
   use File::Basename;
   use File::Spec::Functions qw/abs2rel rel2abs catfile catdir/;
 
+  # Helper function to figure out dependencies on libraries
+  # It takes a list of library names and outputs a list of dependencies
+  sub compute_lib_depends {
+      if ($disabled{shared}) {
+          return map { $_ =~ /\.a$/ ? $`.".OLB" : $_.".OLB" } @_;
+      }
+      return map { $_ =~ /\.a$/
+                   ? $`.".OLB"
+                   : $unified_info{sharednames}->{$_}.".EXE" } @_;
+  }
+
   sub generatesrc {
       my %args = @_;
       my $generator = join(" ", @{$args{generator}});
@@ -627,9 +638,7 @@ EOF
       my $libd = dirname($lib);
       my $libn = basename($lib);
       (my $mkdef_key = $libn) =~ s/^${osslprefix_q}lib([^0-9]*)\d*/$1/i;
-      my @deps = map {
-          $disabled{shared} ? $_.".OLB"
-              : $unified_info{sharednames}->{$_}.".EXE"; } @{$args{deps}};
+      my @deps = compute_lib_depends(@{$args{deps}});
       my $deps = join(", -\n\t\t", @deps);
       my $shlib_target = $disabled{shared} ? "" : $target{shared_target};
       my $ordinalsfile = defined($args{ordinals}) ? $args{ordinals}->[1] : "";
@@ -675,9 +684,7 @@ EOF
       my $libn = basename($lib);
       (my $libn_nolib = $libn) =~ s/^lib//;
       my @objs = map { "$_.OBJ" } @{$args{objs}};
-      my @deps = map {
-          $disabled{shared} ? $_.".OLB"
-              : $unified_info{sharednames}->{$_}.".EXE"; } @{$args{deps}};
+      my @deps = compute_lib_depends(@{$args{deps}});
       my $deps = join(", -\n\t\t", @objs, @deps);
       my $shlib_target = $disabled{shared} ? "" : $target{shared_target};
       my $engine_opt = abs2rel(rel2abs(catfile($config{sourcedir},
@@ -727,9 +734,7 @@ EOF
       my $bind = dirname($bin);
       my $binn = basename($bin);
       my @objs = map { "$_.OBJ" } @{$args{objs}};
-      my @deps = map {
-          $disabled{shared} ? $_.".OLB"
-              : $unified_info{sharednames}->{$_}.".EXE"; } @{$args{deps}};
+      my @deps = compute_lib_depends(@{$args{deps}});
       my $deps = join(", -\n\t\t", @objs, @deps);
       # The "[]" hack is because in .OPT files, each line inherits the
       # previous line's file spec as default, so if no directory spec

Configurations/unix-Makefile.tmpl

@@ -844,13 +844,13 @@ configdata.pm: $(SRCDIR)/Configure $(SRCDIR)/config {- join(" ", @{$config{build
   # It takes a list of library names and outputs a list of dependencies
   sub compute_lib_depends {
       if ($disabled{shared}) {
-          return map { $_.$libext } @_;
+          return map { $_ =~ /\.a$/ ? $`.$libext : $_.$libext } @_;
       }
 
       # Depending on shared libraries:
       # On Windows POSIX layers, we depend on {libname}.dll.a
       # On Unix platforms, we depend on {shlibname}.so
-      return map { shlib_simple($_) } @_;
+      return map { $_ =~ /\.a$/ ? $`.$libext : shlib_simple($_) } @_;
   }
 
   sub generatesrc {
@@ -1073,11 +1073,16 @@ EOF
       my $binn = basename($bin);
       my $objs = join(" ", map { $_.$objext } @{$args{objs}});
       my $deps = join(" ",compute_lib_depends(@{$args{deps}}));
-      my $linklibs = join("", map { my $d = dirname($_);
-                                    my $f = basename($_);
-                                    $d = "." if $d eq $f;
-                                    (my $l = $f) =~ s/^lib//;
-                                    " -L$d -l$l" } @{$args{deps}});
+      my $linklibs = join("", map { if ($_ =~ /\.a$/) {
+                                        " $_";
+                                    } else {
+                                        my $d = dirname($_);
+                                        my $f = basename($_);
+                                        $d = "." if $d eq $f;
+                                        (my $l = $f) =~ s/^lib//;
+                                        " -L$d -l$l"
+                                    }
+                                  } @{$args{deps}});
       my $shlib_target = $disabled{shared} ? "" : $target{shared_target};
       my $cc = '$(CC)';
       my $cflags = '$(CFLAGS) $(BIN_CFLAGS)';

Configurations/windows-makefile.tmpl

@@ -347,8 +347,10 @@ configdata.pm: "$(SRCDIR)\Configure" {- join(" ", map { '"'.$_.'"' } @{$config{b
  # It takes a list of library names and outputs a list of dependencies
  sub compute_lib_depends {
      if ($disabled{shared}) {
-	 return map { $_.$libext } @_;
+	 return map { $_ =~ /\.a$/ ? $`.$libext : $_.$libext } @_;
      }
+     die "Linking with static OpenSSL libraries is not supported in this configuration\n"
+         if grep /\.a$/, @_;
      return map { shlib_import($_) } @_;
  }
 

Configure

@@ -1856,9 +1856,16 @@ EOF
                     $d = cleanfile($buildd, $_, $blddir);
                 }
                 # Take note if the file to depend on is being renamed
+                # Take extra care with files ending with .a, they should
+                # be treated without that extension, and the extension
+                # should be added back after treatment.
+                $d =~ /(\.a)?$/;
+                my $e = $1 // "";
+                $d = $`;
                 if ($unified_info{rename}->{$d}) {
                     $d = $unified_info{rename}->{$d};
                 }
+                $d .= $e;
                 $unified_info{depends}->{$ddest}->{$d} = 1;
                 # If we depend on a header file or a perl module, let's make
                 # sure it can get included