Add a setup hook for fixing dylib install names on Darwin

Install names need to be absolute paths, otherwise programs that link
against the dylib won't work without setting $DYLD_LIBRARY_PATH.  Most
packages do this correctly, but some (like Boost and ICU) do not.
This setup hook absolutizes all install names.

pkgs/build-support/setup-hooks/fix-darwin-dylib-names.sh

@@ -0,0 +1,35 @@
+# On Mac OS X, binaries refer to dynamic library dependencies using
+# either relative paths (e.g. "libicudata.dylib", searched relative to
+# $DYLD_LIBRARY_PATH) or absolute paths
+# (e.g. "/nix/store/.../lib/libicudata.dylib").  In Nix, the latter is
+# preferred since it allows programs to just work.  When linking
+# against a library (e.g. "-licudata"), the linker uses the install
+# name embedded in the dylib (which can be shown using "otool -D").
+# Most packages create dylibs with absolute install names, but some do
+# not.  This setup hook fixes dylibs by setting their install names to
+# their absolute path (using "install_name_tool -id").  It also
+# rewrites references in other dylibs to absolute paths.
+
+fixDarwinDylibNames() {
+    local flags=()
+    local old_id
+
+    for fn in "$@"; do
+        flags+=(-change "$(basename "$fn")" "$fn")
+    done
+
+    for fn in "$@"; do
+        if [ -L "$fn" ]; then continue; fi
+        echo "$fn: fixing dylib"
+        install_name_tool -id "$fn" "${flags[@]}" "$fn"
+    done
+}
+
+fixDarwinDylibNamesIn() {
+    local dir="$1"
+    fixDarwinDylibNames $(find "$dir" -name "*.dylib")
+}
+
+postFixup() {
+    fixDarwinDylibNamesIn "$prefix"
+}

pkgs/development/libraries/boost/1.55.nix

@@ -1,4 +1,4 @@
-{ stdenv, fetchurl, icu, expat, zlib, bzip2, python
+{ stdenv, fetchurl, icu, expat, zlib, bzip2, python, fixDarwinDylibNames
 , toolset ? null
 , enableRelease ? true
 , enableDebug ? false
@@ -59,7 +59,9 @@ stdenv.mkDerivation {
 
   enableParallelBuilding = true;
 
-  buildInputs = [icu expat zlib bzip2 python];
+  buildInputs =
+    [ icu expat zlib bzip2 python ]
+    ++ stdenv.lib.optional stdenv.isDarwin fixDarwinDylibNames;
 
   configureScript = "./bootstrap.sh";
   configureFlags = "--with-icu=${icu} --with-python=${python}/bin/python" + withToolset;

pkgs/development/libraries/http_parser/default.nix

@@ -1,4 +1,4 @@
-{ stdenv, fetchurl, gyp, utillinux, python }:
+{ stdenv, fetchurl, gyp, utillinux, python, fixDarwinDylibNames }:
 
 let
   version = "2.1";
@@ -16,7 +16,10 @@ in stdenv.mkDerivation {
 
   buildFlags = [ "BUILDTYPE=Release" ];
 
-  buildInputs = [ gyp ] ++ (stdenv.lib.optional stdenv.isLinux utillinux) ++ stdenv.lib.optional stdenv.isDarwin python;
+  buildInputs =
+    [ gyp ]
+    ++ stdenv.lib.optional stdenv.isLinux utillinux
+    ++ stdenv.lib.optionals stdenv.isDarwin [ python fixDarwinDylibNames ];
 
   doCheck = !stdenv.isDarwin;
 
@@ -33,11 +36,6 @@ in stdenv.mkDerivation {
     mv http_parser.h $out/include
   '';
 
-  postFixup = if stdenv.isDarwin then ''
-    install_name_tool -id $out/lib/libhttp_parser.dylib $out/lib/libhttp_parser.dylib
-    install_name_tool -id $out/lib/libhttp_parser_strict.dylib $out/lib/libhttp_parser_strict.dylib
-  '' else null;
-
   meta = {
     description = "An HTTP message parser written in C";
 

pkgs/development/libraries/icu/default.nix

@@ -1,4 +1,4 @@
-{stdenv, fetchurl}:
+{ stdenv, fetchurl, fixDarwinDylibNames }:
 
 let
 
@@ -16,6 +16,10 @@ stdenv.mkDerivation {
     sha256 = "14l0kl17nirc34frcybzg0snknaks23abhdxkmsqg3k9sil5wk9g";
   };
 
+  # FIXME: This fixes dylib references in the dylibs themselves, but
+  # not in the programs in $out/bin.
+  buildInputs = stdenv.lib.optional stdenv.isDarwin fixDarwinDylibNames;
+
   postUnpack = ''
     sourceRoot=''${sourceRoot}/source
     echo Source root reset to ''${sourceRoot}

pkgs/top-level/all-packages.nix

@@ -394,6 +394,8 @@ let
 
   setJavaClassPath = makeSetupHook { } ../build-support/setup-hooks/set-java-classpath.sh;
 
+  fixDarwinDylibNames = makeSetupHook { } ../build-support/setup-hooks/fix-darwin-dylib-names.sh;
+
 
   ### TOOLS