michael@0: #!/bin/bash
michael@0: 
michael@0: # Copyright (c) 2012 The Chromium Authors. All rights reserved.
michael@0: # Use of this source code is governed by a BSD-style license that can be
michael@0: # found in the LICENSE file.
michael@0: 
michael@0: # Copies a framework to its new home, "unversioning" it.
michael@0: #
michael@0: # Normally, frameworks are versioned bundles.  The contents of a framework are
michael@0: # stored in a versioned directory within the bundle, and symbolic links
michael@0: # provide access to the actual code and resources.  See
michael@0: # http://developer.apple.com/mac/library/documentation/MacOSX/Conceptual/BPFrameworks/Concepts/FrameworkAnatomy.html
michael@0: #
michael@0: # The symbolic links usually found in frameworks create problems.  Symbolic
michael@0: # links are excluded from code signatures.  That means that it's possible to
michael@0: # remove or retarget a symbolic link within a framework without affecting the
michael@0: # seal.  In Chrome's case, the outer .app bundle contains a framework where
michael@0: # all application code and resources live.  In order for the signature on the
michael@0: # .app to be meaningful, it encompasses the framework.  Because framework
michael@0: # resources are accessed through the framework's symbolic links, this
michael@0: # arrangement results in a case where the resources can be altered without
michael@0: # affecting the .app signature's validity.
michael@0: #
michael@0: # Indirection through symbolic links also carries a runtime performance
michael@0: # penalty on open() operations, although open() typically completes so quickly
michael@0: # that this is not considered a major performance problem.
michael@0: #
michael@0: # To resolve these problems, the frameworks that ship within Chrome's .app
michael@0: # bundle are unversioned.  Unversioning is simple: instead of using the
michael@0: # original outer .framework directory as the framework that ships within the
michael@0: # .app, the inner versioned directory is used.  Instead of accessing bundled
michael@0: # resources through symbolic links, they are accessed directly.  In normal
michael@0: # situations, the only hard-coded use of the versioned directory is by dyld,
michael@0: # when loading the framework's code, but this is handled through a normal
michael@0: # Mach-O load command, and it is easy to adjust the load command to point to
michael@0: # the unversioned framework code rather than the versioned counterpart.
michael@0: #
michael@0: # The resulting framework bundles aren't strictly conforming, but they work
michael@0: # as well as normal versioned framework bundles.
michael@0: #
michael@0: # An option to skip running install_name_tool is available. By passing -I as
michael@0: # the first argument to this script, install_name_tool will be skipped. This
michael@0: # is only suitable for copied frameworks that will not be linked against, or
michael@0: # when install_name_tool will be run on any linker output when something is
michael@0: # linked against the copied framework. This option exists to allow signed
michael@0: # frameworks to pass through without subjecting them to any modifications that
michael@0: # would break their signatures.
michael@0: 
michael@0: set -e
michael@0: 
michael@0: RUN_INSTALL_NAME_TOOL=1
michael@0: if [ $# -eq 3 ] && [ "${1}" = "-I" ] ; then
michael@0:   shift
michael@0:   RUN_INSTALL_NAME_TOOL=
michael@0: fi
michael@0: 
michael@0: if [ $# -ne 2 ] ; then
michael@0:   echo "usage: ${0} [-I] FRAMEWORK DESTINATION_DIR" >& 2
michael@0:   exit 1
michael@0: fi
michael@0: 
michael@0: # FRAMEWORK should be a path to a versioned framework bundle, ending in
michael@0: # .framework.  DESTINATION_DIR is the directory that the unversioned framework
michael@0: # bundle will be copied to.
michael@0: 
michael@0: FRAMEWORK="${1}"
michael@0: DESTINATION_DIR="${2}"
michael@0: 
michael@0: FRAMEWORK_NAME="$(basename "${FRAMEWORK}")"
michael@0: if [ "${FRAMEWORK_NAME: -10}" != ".framework" ] ; then
michael@0:   echo "${0}: ${FRAMEWORK_NAME} does not end in .framework" >& 2
michael@0:   exit 1
michael@0: fi
michael@0: FRAMEWORK_NAME_NOEXT="${FRAMEWORK_NAME:0:$((${#FRAMEWORK_NAME} - 10))}"
michael@0: 
michael@0: # Find the current version.
michael@0: VERSIONS="${FRAMEWORK}/Versions"
michael@0: CURRENT_VERSION_LINK="${VERSIONS}/Current"
michael@0: CURRENT_VERSION_ID="$(readlink "${VERSIONS}/Current")"
michael@0: CURRENT_VERSION="${VERSIONS}/${CURRENT_VERSION_ID}"
michael@0: 
michael@0: # Make sure that the framework's structure makes sense as a versioned bundle.
michael@0: if [ ! -e "${CURRENT_VERSION}/${FRAMEWORK_NAME_NOEXT}" ] ; then
michael@0:   echo "${0}: ${FRAMEWORK_NAME} does not contain a dylib" >& 2
michael@0:   exit 1
michael@0: fi
michael@0: 
michael@0: DESTINATION="${DESTINATION_DIR}/${FRAMEWORK_NAME}"
michael@0: 
michael@0: # Copy the versioned directory within the versioned framework to its
michael@0: # destination location.
michael@0: mkdir -p "${DESTINATION_DIR}"
michael@0: rsync -acC --delete --exclude Headers --exclude PrivateHeaders \
michael@0:     --include '*.so' "${CURRENT_VERSION}/" "${DESTINATION}"
michael@0: 
michael@0: if [[ -n "${RUN_INSTALL_NAME_TOOL}" ]]; then
michael@0:   # Adjust the Mach-O LC_ID_DYLIB load command in the framework.  This does not
michael@0:   # change the LC_LOAD_DYLIB load commands in anything that may have already
michael@0:   # linked against the framework.  Not all frameworks will actually need this
michael@0:   # to be changed.  Some frameworks may already be built with the proper
michael@0:   # LC_ID_DYLIB for use as an unversioned framework.  Xcode users can do this
michael@0:   # by setting LD_DYLIB_INSTALL_NAME to
michael@0:   # $(DYLIB_INSTALL_NAME_BASE:standardizepath)/$(WRAPPER_NAME)/$(PRODUCT_NAME)
michael@0:   # If invoking ld via gcc or g++, pass the desired path to -Wl,-install_name
michael@0:   # at link time.
michael@0:   FRAMEWORK_DYLIB="${DESTINATION}/${FRAMEWORK_NAME_NOEXT}"
michael@0:   LC_ID_DYLIB_OLD="$(otool -l "${FRAMEWORK_DYLIB}" |
michael@0:                          grep -A10 "^ *cmd LC_ID_DYLIB$" |
michael@0:                          grep -m1 "^ *name" |
michael@0:                          sed -Ee 's/^ *name (.*) \(offset [0-9]+\)$/\1/')"
michael@0:   VERSION_PATH="/Versions/${CURRENT_VERSION_ID}/${FRAMEWORK_NAME_NOEXT}"
michael@0:   LC_ID_DYLIB_NEW="$(echo "${LC_ID_DYLIB_OLD}" |
michael@0:                      sed -Ee "s%${VERSION_PATH}$%/${FRAMEWORK_NAME_NOEXT}%")"
michael@0: 
michael@0:   if [ "${LC_ID_DYLIB_NEW}" != "${LC_ID_DYLIB_OLD}" ] ; then
michael@0:     install_name_tool -id "${LC_ID_DYLIB_NEW}" "${FRAMEWORK_DYLIB}"
michael@0:   fi
michael@0: fi