Allow re-targeting of naclports install

examples/games/snes9x-1.53/nacl-snes9x-1.53.sh

 #!/bin/bash
 # Copyright (c) 2012 The Native Client Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 #
 
 # nacl-snes-1.53.sh
 #
 # Usage:  nacl-snes-1.53.sh
 #
 # This script downloads, patches, and builds an snes9x-based SNES emulator for
 # Native Client.
 
 source pkg_info
 source ../../../build_tools/common.sh
 
 DOSBOX_EXAMPLE_DIR=${NACL_SRC}/examples/games/snes9x-1.53
 
 CustomConfigureStep() {
   Banner "Configuring ${PACKAGE_NAME}"
 
   # export the nacl tools
   export CC=${NACLCC}
   export CXX=${NACLCXX}
-  export CXXFLAGS="-I${NACL_SDK_ROOT}/include"
-  export LDFLAGS=""
+  export CXXFLAGS="${NACLPORTS_CFLAGS} -I${NACL_SDK_ROOT}/include"
+  export LDFLAGS="${NACLPORTS_LDFLAGS}"
   if [ ${NACL_ARCH} = "pnacl" ] ; then
-    export CXXFLAGS="-O3 -g"
-    export LDFLAGS="-O0 -static"
+    export CXXFLAGS="${NACLPORTS_CFLAGS} -O3 -g"
+    export LDFLAGS="${NACLPORTS_LDFLAGS} -O0 -static"
   fi
   export AR=${NACLAR}
   export RANLIB=${NACLRANLIB}
-  export PKG_CONFIG_PATH=${NACL_SDK_USR_LIB}/pkgconfig
-  export PKG_CONFIG_LIBDIR=${NACL_SDK_USR_LIB}
+  export PKG_CONFIG_PATH=${NACLPORTS_LIBDIR}/pkgconfig
+  export PKG_CONFIG_LIBDIR=${NACLPORTS_LIBDIR}
 
   CONFIG_FLAGS="--host=nacl \
-      --prefix=${NACL_SDK_USR} \
-      --exec-prefix=${NACL_SDK_USR} \
-      --libdir=${NACL_SDK_USR_LIB} \
-      --oldincludedir=${NACL_SDK_USR_INCLUDE} \
+      --prefix=${NACLPORTS_PREFIX} \
+      --exec-prefix=${NACLPORTS_PREFIX} \
+      --libdir=${NACLPORTS_LIBDIR} \
+      --oldincludedir=${NACLPORTS_INCLUDE} \
       --disable-gamepad \
       --disable-gzip \
       --disable-zip \
       --disable-jma \
       --disable-screenshot \
       --disable-netplay \
       --without-x \
       --enable-sound"
 
-  export LIBS="-L${NACL_SDK_USR_LIB} \
+  export LIBS="-L${NACLPORTS_LIBDIR} \
       -lnacl-mounts -lppapi_cpp -lppapi \
       -lpthread -lstdc++"
 
   ChangeDir ${NACL_PACKAGES_REPOSITORY}/${PACKAGE_NAME}-src/unix
   cp -f ${START_DIR}/pepper.cpp .
   cp -f ${START_DIR}/nacl.h .
   cp -f ${START_DIR}/nacl.cpp .
   cp -f ${START_DIR}/event_queue.h .
   autoconf && ./configure ${CONFIG_FLAGS}
 }
@@ skipping 21 matching lines @@
   if [ ${NACL_ARCH} = "pnacl" ] ; then
     # NOTE: snes9x has unusual dirnames
     DefaultTranslateStep ${PACKAGE_NAME}-src unix/snes9x
   fi
   CustomInstallStep
   DefaultCleanUpStep
 }
 
 CustomPackageInstall
 exit 0