Introduce the "pic" / "no-pic" config option

Building shared libraries or not is not the same as building position
independent code or not.  It's true that if you don't build PIC, you
can't build shared libraries.  However, you may very well want to
build only static libraries but still want PIC code.

Therefore, we introduce a new configuration option "pic", which is
enabled by default or explicitely with "enable-pic", or disabled with
"no-pic" or "disable-pic".  Of course, if "pic" is disabled, "shared"
and "dynamic-engine" are automatically disabled as well.

Reviewed-by: Rich Salz <rsalz@openssl.org>

diff --git a/Configure b/Configure
index 2435e03f5b9724ee4e5bb3557ee60ba19111d390..7942a593b8fa54b91da10eee3c9522d3f8d296c1 100755 (executable)
--- a/Configure
+++ b/Configure
@@ -46,6 +46,8 @@ my $usage="Usage: Configure [no-<cipher> ...] [enable-<cipher> ...] [-Dxxx] [-lx
 #               multithreaded applications (default is "threads" if we
 #               know how to do it)
 # [no-]shared  [don't] try to create shared libraries when supported.
+# [no-]pic      [don't] try to build position independent code when supported.
+#               If disabled, it also disables shared and dynamic-engines.
 # no-asm        do not use assembler
 # no-dso        do not compile in any native shared-library methods. This
 #               will ensure that all methods just return NULL.
@@ -284,6 +286,7 @@ my @disablables = (
     "nextprotoneg",
     "ocb",
     "ocsp",
+    "pic",
     "poly1305",
     "posix-io",
     "psk",
@@ -384,6 +387,9 @@ my @disable_cascades = (
 
     # Without DSO, we can't load dynamic engines, so don't build them dynamic
     "dso"               => [ "dynamic-engine" ],
+
+    # Without position independent code, there can be no shared libraries or DSOs
+    "pic"               => [ "shared", "dynamic-engine" ],
     );
 
 # Avoid protocol support holes.  Also disable all versions below N, if version
@@ -764,6 +770,8 @@ foreach (sort (keys %disabled))
                { $no_threads = 1; }
        elsif (/^shared$/)
                { $config{no_shared} = 1; }
+       elsif (/^pic$/)
+               { }
        elsif (/^zlib$/)
                { $zlib = 0; }
        elsif (/^dynamic-engine$/)
@@ -1000,8 +1008,12 @@ if (defined($disabled{"deprecated"})) {
 
 if ($target{shared_target} eq "")
        {
-       $no_shared_warn = 1 if !$config{no_shared} && !$config{fips};
+       $no_shared_warn = 1
+           if ((!$config{no_shared} || !$disabled{"dynamic-engine"})
+               && !$config{fips});
        $config{no_shared} = 1;
+       $disabled{pic} = $disabled{shared} = $disabled{"dynamic-engine"} =
+           "no-shared-target";
        }
 
 if ($disabled{"dynamic-engine"}) {
@@ -1015,6 +1027,14 @@ if ($disabled{"dynamic-engine"}) {
 #
 # Platform fix-ups
 #
+
+# This saves the build files from having to check
+if ($disabled{pic})
+       {
+       $target{shared_cflag} = $target{shared_ldflag} =
+               $target{shared_rcflag} = "";
+       }
+
 if ($target{sys_id} ne "")
        {
        push @{$config{openssl_sys_defines}}, "OPENSSL_SYS_$target{sys_id}";
@@ -1049,7 +1069,7 @@ if (!$no_asm) {
     if ($target{md5_asm_src}) {
        push @{$config{defines}}, "MD5_ASM";
     }
-    $target{cast_asm_src}=$table{BASE}->{cast_asm_src} if (!$config{no_shared}); # CAST assembler is not PIC
+    $target{cast_asm_src}=$table{BASE}->{cast_asm_src} unless $disabled{pic}; # CAST assembler is not PIC
     if ($target{rmd160_asm_src}) {
        push @{$config{defines}}, "RMD160_ASM";
     }
@@ -1849,10 +1869,11 @@ EOF
 
 print <<"EOF" if ($no_shared_warn);
 
-You gave the option 'shared', which is not supported on this platform, so
-we will pretend you gave the option 'no-shared'.  If you know how to implement
-shared libraries, please let us know (but please first make sure you have
-tried with a current version of OpenSSL).
+The options 'shared', 'pic' and 'dynamic-engine' aren't supported on this
+platform, so we will pretend you gave the option 'no-pic', which also disables
+'shared' and 'dynamic-engine'.  If you know how to implement shared libraries
+or position independent code, please let us know (but please first make sure
+you have tried with a current version of OpenSSL).
 EOF
 
 ###### TO BE REMOVED BEFORE FINAL RELEASE