libdaemon: Add patch to fix musl build

pkgs/development/libraries/libdaemon/default.nix

@@ -1,6 +1,6 @@
 {stdenv, fetchurl}:
 
-stdenv.mkDerivation rec {
+stdenv.mkDerivation (rec {
   name = "libdaemon-0.14";
 
   src = fetchurl {
@@ -24,4 +24,8 @@ stdenv.mkDerivation rec {
     platforms = stdenv.lib.platforms.unix;
     maintainers = [ ];
   };
-}
+} // stdenv.lib.optionalAttrs stdenv.hostPlatform.isMusl {
+  # This patch should be applied unconditionally, but doing so will cause mass rebuild.
+  patches = ./fix-includes.patch;
+})
+

pkgs/development/libraries/libdaemon/fix-includes.patch

@@ -0,0 +1,13 @@
+--- libdaemon-0.14.orig/examples/testd.c
++++ libdaemon-0.14/examples/testd.c
+@@ -21,9 +21,9 @@
+ #include <signal.h>
+ #include <errno.h>
+ #include <string.h>
++#include <unistd.h>
+ #include <sys/types.h>
+ #include <sys/time.h>
+-#include <sys/unistd.h>
+ #include <sys/select.h>
+ 
+ #include <libdaemon/dfork.h>