[bug#67675] [PATCH] gnu: dante: Enable preloading support.

[Nguyễn Gia Phong]

Dante uses dlopen which doesn't work with libc.so but libc.so.6.
This fixes socksify, which is patched to skip invoking uname needlessly.

* gnu/packages/networking.scm (dante): Enable preloading support.
* gnu/packages/patches/dante-non-darwin.patch: New file.

References: https://github.com/NixOS/nixpkgs/pull/68418#discussion_r343625853
Fixes: https://issues.guix.gnu.org/63250
Change-Id: I03a5b6b6e11cf6a0453a4968ff00c6dd627249a8
---
 gnu/packages/networking.scm                 |  9 +++------
 gnu/packages/patches/dante-non-darwin.patch | 15 +++++++++++++++
 2 files changed, 18 insertions(+), 6 deletions(-)
 create mode 100644 gnu/packages/patches/dante-non-darwin.patch

diff --git a/gnu/packages/networking.scm b/gnu/packages/networking.scm
index 6b415076e89f..13ac08aa253d 100644
--- a/gnu/packages/networking.scm
+++ b/gnu/packages/networking.scm
@@ -3640,13 +3640,10 @@ (define-public dante
        (uri (string-append "https://www.inet.no/dante/files/dante-";
                            version ".tar.gz"))
        (sha256
-        (base32 "0pbahkj43rx7rmv2x40mf5p3g3x9d6i2sz7pzglarf54w5ghd2j1"))))
+         (base32 "0pbahkj43rx7rmv2x40mf5p3g3x9d6i2sz7pzglarf54w5ghd2j1"))
+       (patches (search-patches "dante-non-darwin.patch"))))
     (build-system gnu-build-system)
-    (arguments
-     ;; XXX: The dynamic socks library doesn't work with 'libc.so' (GNU ld
-     ;; script).  When preloading is enabled, 'sockd' failed with:
-     ;;    … Failed to open library "libc.so": …: invalid ELF header
-     '(#:configure-flags '("--disable-preload")))
+    (arguments '(#:configure-flags '("--with-libc=libc.so.6")))
     (home-page "https://www.inet.no/dante/";)
     (synopsis "SOCKS server and client")
     (description "Dante is a SOCKS client and server implementation.  It can
diff --git a/gnu/packages/patches/dante-non-darwin.patch 
b/gnu/packages/patches/dante-non-darwin.patch
new file mode 100644
index 000000000000..0ecb705c78b7
--- /dev/null
+++ b/gnu/packages/patches/dante-non-darwin.patch
@@ -0,0 +1,15 @@
+Disable runtime check for Darwin so we don't have to substitute uname.
+--- a/bin/socksify.in
++++ b/bin/socksify.in
+@@ -65,11 +65,6 @@
+     unset FULLPATH
+ fi
+ 
+-#use "FLAT_NAMESPACE" on Darwin in attempt to match LD_PRELOAD behavior
+-if test x`uname` = xDarwin; then
+-    export DYLD_FORCE_FLAT_NAMESPACE=t
+-fi
+-
+ #dlib/Makefile.am libtool flags should produce a predictable library name
+ #(ending in SOLIB_POSTFIX).
+ LIBRARY="${SOCKS_LIBRARY:-${FULLPATH}libdsocks.@SOLIB_POSTFIX@}"

base-commit: 4e7cb241188cf9f213d5fbabbabce07d35ca0991
-- 
2.41.0