1 #!/bin/bash 2 3 # Copyright (c) 2012 The Chromium Authors. All rights reserved. 4 # Use of this source code is governed by a BSD-style license that can be 5 # found in the LICENSE file. 6 7 # Copies a framework to its new home, "unversioning" it. 8 # 9 # Normally, frameworks are versioned bundles. The contents of a framework are 10 # stored in a versioned directory within the bundle, and symbolic links 11 # provide access to the actual code and resources. See 12 # http://developer.apple.com/mac/library/documentation/MacOSX/Conceptual/BPFrameworks/Concepts/FrameworkAnatomy.html 13 # 14 # The symbolic links usually found in frameworks create problems. Symbolic 15 # links are excluded from code signatures. That means that it's possible to 16 # remove or retarget a symbolic link within a framework without affecting the 17 # seal. In Chrome's case, the outer .app bundle contains a framework where 18 # all application code and resources live. In order for the signature on the 19 # .app to be meaningful, it encompasses the framework. Because framework 20 # resources are accessed through the framework's symbolic links, this 21 # arrangement results in a case where the resources can be altered without 22 # affecting the .app signature's validity. 23 # 24 # Indirection through symbolic links also carries a runtime performance 25 # penalty on open() operations, although open() typically completes so quickly 26 # that this is not considered a major performance problem. 27 # 28 # To resolve these problems, the frameworks that ship within Chrome's .app 29 # bundle are unversioned. Unversioning is simple: instead of using the 30 # original outer .framework directory as the framework that ships within the 31 # .app, the inner versioned directory is used. Instead of accessing bundled 32 # resources through symbolic links, they are accessed directly. In normal 33 # situations, the only hard-coded use of the versioned directory is by dyld, 34 # when loading the framework's code, but this is handled through a normal 35 # Mach-O load command, and it is easy to adjust the load command to point to 36 # the unversioned framework code rather than the versioned counterpart. 37 # 38 # The resulting framework bundles aren't strictly conforming, but they work 39 # as well as normal versioned framework bundles. 40 # 41 # An option to skip running install_name_tool is available. By passing -I as 42 # the first argument to this script, install_name_tool will be skipped. This 43 # is only suitable for copied frameworks that will not be linked against, or 44 # when install_name_tool will be run on any linker output when something is 45 # linked against the copied framework. This option exists to allow signed 46 # frameworks to pass through without subjecting them to any modifications that 47 # would break their signatures. 48 49 set -e 50 51 RUN_INSTALL_NAME_TOOL=1 52 if [ $# -eq 3 ] && [ "${1}" = "-I" ] ; then 53 shift 54 RUN_INSTALL_NAME_TOOL= 55 fi 56 57 if [ $# -ne 2 ] ; then 58 echo "usage: ${0} [-I] FRAMEWORK DESTINATION_DIR" >& 2 59 exit 1 60 fi 61 62 # FRAMEWORK should be a path to a versioned framework bundle, ending in 63 # .framework. DESTINATION_DIR is the directory that the unversioned framework 64 # bundle will be copied to. 65 66 FRAMEWORK="${1}" 67 DESTINATION_DIR="${2}" 68 69 FRAMEWORK_NAME="$(basename "${FRAMEWORK}")" 70 if [ "${FRAMEWORK_NAME: -10}" != ".framework" ] ; then 71 echo "${0}: ${FRAMEWORK_NAME} does not end in .framework" >& 2 72 exit 1 73 fi 74 FRAMEWORK_NAME_NOEXT="${FRAMEWORK_NAME:0:$((${#FRAMEWORK_NAME} - 10))}" 75 76 # Find the current version. 77 VERSIONS="${FRAMEWORK}/Versions" 78 CURRENT_VERSION_LINK="${VERSIONS}/Current" 79 CURRENT_VERSION_ID="$(readlink "${VERSIONS}/Current")" 80 CURRENT_VERSION="${VERSIONS}/${CURRENT_VERSION_ID}" 81 82 # Make sure that the framework's structure makes sense as a versioned bundle. 83 if [ ! -e "${CURRENT_VERSION}/${FRAMEWORK_NAME_NOEXT}" ] ; then 84 echo "${0}: ${FRAMEWORK_NAME} does not contain a dylib" >& 2 85 exit 1 86 fi 87 88 DESTINATION="${DESTINATION_DIR}/${FRAMEWORK_NAME}" 89 90 # Copy the versioned directory within the versioned framework to its 91 # destination location. 92 mkdir -p "${DESTINATION_DIR}" 93 rsync -acC --delete --exclude Headers --exclude PrivateHeaders \ 94 --include '*.so' "${CURRENT_VERSION}/" "${DESTINATION}" 95 96 if [[ -n "${RUN_INSTALL_NAME_TOOL}" ]]; then 97 # Adjust the Mach-O LC_ID_DYLIB load command in the framework. This does not 98 # change the LC_LOAD_DYLIB load commands in anything that may have already 99 # linked against the framework. Not all frameworks will actually need this 100 # to be changed. Some frameworks may already be built with the proper 101 # LC_ID_DYLIB for use as an unversioned framework. Xcode users can do this 102 # by setting LD_DYLIB_INSTALL_NAME to 103 # $(DYLIB_INSTALL_NAME_BASE:standardizepath)/$(WRAPPER_NAME)/$(PRODUCT_NAME) 104 # If invoking ld via gcc or g++, pass the desired path to -Wl,-install_name 105 # at link time. 106 FRAMEWORK_DYLIB="${DESTINATION}/${FRAMEWORK_NAME_NOEXT}" 107 LC_ID_DYLIB_OLD="$(otool -l "${FRAMEWORK_DYLIB}" | 108 grep -A10 "^ *cmd LC_ID_DYLIB$" | 109 grep -m1 "^ *name" | 110 sed -Ee 's/^ *name (.*) \(offset [0-9]+\)$/\1/')" 111 VERSION_PATH="/Versions/${CURRENT_VERSION_ID}/${FRAMEWORK_NAME_NOEXT}" 112 LC_ID_DYLIB_NEW="$(echo "${LC_ID_DYLIB_OLD}" | 113 sed -Ee "s%${VERSION_PATH}$%/${FRAMEWORK_NAME_NOEXT}%")" 114 115 if [ "${LC_ID_DYLIB_NEW}" != "${LC_ID_DYLIB_OLD}" ] ; then 116 install_name_tool -id "${LC_ID_DYLIB_NEW}" "${FRAMEWORK_DYLIB}" 117 fi 118 fi 119
