# MacOS Deployment The `macdeployqtplus` script should not be run manually. Instead, after building as usual: ```bash make deploy ``` During the deployment process, the disk image window will pop up briefly when the fancy settings are applied. This is normal, please do not interfere, the process will unmount the DMG and cleanup before finishing. When complete, it will have produced `Dash-Qt.dmg`. ## SDK Extraction `Xcode.app` is packaged in a `.xip` archive. This makes the SDK less-trivial to extract on non-macOS machines. One approach (tested on Debian Buster) is outlined below: ```bash apt install clang cpio git liblzma-dev libxml2-dev libssl-dev make git clone https://github.com/tpoechtrager/xar pushd xar/xar ./configure make make install popd git clone https://github.com/NiklasRosenstein/pbzx pushd pbzx clang -llzma -lxar pbzx.c -o pbzx -Wl,-rpath=/usr/local/lib popd xar -xf Xcode_10.2.1.xip -C . ./pbzx/pbzx -n Content | cpio -i find Xcode.app -type d -name MacOSX.sdk -execdir sh -c 'tar -c MacOSX.sdk/ | gzip -9n > /MacOSX10.14.sdk.tar.gz' \; ``` on macOS the process is more straightforward: ```bash xip -x Xcode_10.2.1.xip tar -C Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/ -czf MacOSX10.14.sdk.tar.gz MacOSX.sdk ``` Our previously used macOS SDK (`MacOSX10.11.sdk`) can be extracted from [Xcode 7.3.1 dmg](https://developer.apple.com/devcenter/download.action?path=/Developer_Tools/Xcode_7.3.1/Xcode_7.3.1.dmg). The script [`extract-osx-sdk.sh`](./extract-osx-sdk.sh) automates this. First ensure the DMG file is in the current directory, and then run the script. You may wish to delete the `intermediate 5.hfs` file and `MacOSX10.11.sdk` (the directory) when you've confirmed the extraction succeeded. ```bash apt-get install p7zip-full sleuthkit contrib/macdeploy/extract-osx-sdk.sh rm -rf 5.hfs MacOSX10.11.sdk ``` ## Deterministic macOS DMG Notes Working macOS DMGs are created in Linux by combining a recent `clang`, the Apple `binutils` (`ld`, `ar`, etc) and DMG authoring tools. Apple uses `clang` extensively for development and has upstreamed the necessary functionality so that a vanilla clang can take advantage. It supports the use of `-F`, `-target`, `-mmacosx-version-min`, and `--sysroot`, which are all necessary when building for macOS. Apple's version of `binutils` (called `cctools`) contains lots of functionality missing in the FSF's `binutils`. In addition to extra linker options for frameworks and sysroots, several other tools are needed as well such as `install_name_tool`, `lipo`, and `nmedit`. These do not build under Linux, so they have been patched to do so. The work here was used as a starting point: [mingwandroid/toolchain4](https://github.com/mingwandroid/toolchain4). In order to build a working toolchain, the following source packages are needed from Apple: `cctools`, `dyld`, and `ld64`. These tools inject timestamps by default, which produce non-deterministic binaries. The `ZERO_AR_DATE` environment variable is used to disable that. This version of `cctools` has been patched to use the current version of `clang`'s headers and its `libLTO.so` rather than those from `llvmgcc`, as it was originally done in `toolchain4`. To complicate things further, all builds must target an Apple SDK. These SDKs are free to download, but not redistributable. To obtain it, register for an Apple Developer Account, then download [Xcode 10.2.1](https://download.developer.apple.com/Developer_Tools/Xcode_10.2.1/Xcode_10.2.1.xip). This file is many gigabytes in size, but most (but not all) of what we need is contained only in a single directory: ```bash Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.14.sdk ``` See the SDK Extraction notes above for how to obtain it. The Gitian descriptors build 2 sets of files: Linux tools, then Apple binaries which are created using these tools. The build process has been designed to avoid including the SDK's files in Gitian's outputs. All interim tarballs are fully deterministic and may be freely redistributed. `genisoimage` is used to create the initial DMG. It is not deterministic as-is, so it has been patched. A system `genisoimage` will work fine, but it will not be deterministic because the file-order will change between invocations. The patch can be seen here: [cdrkit-deterministic.patch](https://github.com/bitcoin/bitcoin/blob/master/depends/patches/native_cdrkit/cdrkit-deterministic.patch). No effort was made to fix this cleanly, so it likely leaks memory badly, however it's only used for a single invocation, so that's no real concern. `genisoimage` cannot compress DMGs, so afterwards, the DMG tool from the `libdmg-hfsplus` project is used to compress it. There are several bugs in this tool and its maintainer has seemingly abandoned the project. The DMG tool has the ability to create DMGs from scratch as well, but this functionality is broken. Only the compression feature is currently used. Ideally, the creation could be fixed and `genisoimage` would no longer be necessary. Background images and other features can be added to DMG files by inserting a `.DS_Store` before creation. This is generated by the script `contrib/macdeploy/custom_dsstore.py`. As of OS X 10.9 Mavericks, using an Apple-blessed key to sign binaries is a requirement in order to satisfy the new Gatekeeper requirements. Because this private key cannot be shared, we'll have to be a bit creative in order for the build process to remain somewhat deterministic. Here's how it works: - Builders use Gitian to create an unsigned release. This outputs an unsigned DMG which users may choose to bless and run. It also outputs an unsigned app structure in the form of a tarball, which also contains all of the tools that have been previously (deterministically) built in order to create a final DMG. - The Apple keyholder uses this unsigned app to create a detached signature, using the script that is also included there. Detached signatures are available. - Builders feed the unsigned app + detached signature back into Gitian. It uses the pre-built tools to recombine the pieces into a deterministic DMG.