Update Crashpad to b47bf6c250c6b825dee1c5fbad9152c2c962e828

third_party/crashpad/crashpad/doc/developing.ad

 // Copyright 2015 The Crashpad Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
@@ skipping 20 matching lines @@
 https://chromium.googlesource.com/chromium/mini_chromium/+/master/README[mini_chromium’s
 README] provides more detail.
 
 == Prerequisites
 
 To develop Crashpad, the following tools are necessary, and must be
 present in the `$PATH` environment variable:
 
  * Chromium’s
    https://dev.chromium.org/developers/how-tos/depottools[depot_tools].
- * http://git-scm.com/[Git]. This is provided by Xcode on Mac OS X and by
+ * https://git-scm.com/[Git]. This is provided by Xcode on Mac OS X and by
    depot_tools on Windows.
  * https://www.python.org/[Python]. This is provided by the operating system on
    Mac OS X, and by depot_tools on Windows.
  * Appropriate development tools. For Mac OS X, this is
    https://developer.apple.com/xcode/[Xcode], and for Windows, it’s
    https://www.visualstudio.com/[Visual Studio].
 
 == Getting the Source Code
 
 The main source code repository is a Git repository hosted at
@@ skipping 10 matching lines @@
 
 === Initial Checkout
 
 [subs="verbatim,quotes"]
 ----
 $ *mkdir \~/crashpad*
 $ *cd ~/crashpad*
 $ *fetch crashpad*
 ----
 
-`fetch crashpad` performs the initial `gclient sync`, establishing a
-fully-functional local checkout.
+`fetch crashpad` performs the initial `git clone` and `gclient sync`,
+establishing a fully-functional local checkout.
 
 === Subsequent Checkouts
 
 [subs="verbatim,quotes"]
 ----
 $ *cd ~/crashpad/crashpad*
 $ *git pull -r*
 $ *gclient sync*
 ----
 
 == Building
 
 Crashpad uses https://gyp.gsrc.io/[GYP] to generate
-https://martine.github.io/ninja/[Ninja] build files. The build is described by
-`.gyp` files throughout the Crashpad source code tree. The
-`build/gyp_crashpad.py` script runs GYP properly for Crashpad, and is also
-called when you run `fetch crashpad`, `gclient sync`, or `gclient runhooks`.
+https://ninja-build.org/[Ninja] build files. The build is described by `.gyp`
+files throughout the Crashpad source code tree. The `build/gyp_crashpad.py`
+script runs GYP properly for Crashpad, and is also called when you run `fetch
+crashpad`, `gclient sync`, or `gclient runhooks`.
 
 The Ninja build files and build output are in the `out` directory. Both debug-
 and release-mode configurations are available. The examples below show the debug
 configuration. To build and test the release configuration, substitute `Release`
 for `Debug`.
 
 [subs="verbatim,quotes"]
 ----
 $ *cd ~/crashpad/crashpad*
 $ *ninja -C out/Debug*
 ----
 
 Ninja is part of the
 https://dev.chromium.org/developers/how-tos/depottools[depot_tools]. There’s no
 need to install it separately.
 
+=== Android
+
+Crashpad’s Android port is in its early stages. This build relies on
+cross-compilation. It’s possible to develop Crashpad for Android on any platform
+that the https://developer.android.com/ndk/[Android NDK (Native Development
+Kit)] runs on.
+
+If it’s not already present on your system,
+https://developer.android.com/ndk/downloads/[download the NDK package for your
+system] and expand it to a suitable location. These instructions assume that
+it’s been expanded to `~/android-ndk-r13`.
+
+To build Crashpad, portions of the NDK must be reassembled into a
+https://developer.android.com/ndk/guides/standalone_toolchain.html[standalone
+toolchain]. This is a repackaged subset of the NDK suitable for cross-compiling
+for a single Android architecture (such as `arm`, `arm64`, `x86`, and `x86_64`)
+targeting a specific
+https://source.android.com/source/build-numbers.html[Android API level]. The
+standalone toolchain only needs to be built from the NDK one time for each set
+of options desired. To build a standalone toolchain targeting 64-bit ARM and API
+level 21 (Android 5.0 “Lollipop”), run:
+
+[subs="verbatim,quotes"]
+----
+$ *cd ~*
+$ *python android-ndk-r13/build/tools/make_standalone_toolchain.py \
+      --arch=arm64 --api=21 --install-dir=android-ndk-r13_arm64_api21*
+----
+
+Note that Chrome uses Android API level 21 for 64-bit platforms and 16 for
+32-bit platforms. See Chrome’s
+https://chromium.googlesource.com/chromium/src/+/master/build/config/android/config.gni[`build/config/android/config.gni`]
+which sets `_android_api_level` and `_android64_api_level`.
+
+To configure a Crashpad build for Android using this standalone toolchain,
+set several environment variables directing the build to the standalone
+toolchain, along with GYP options to identify an Android build. This must be
+done after any `gclient sync`, or instead of any `gclient runhooks` operation.
+The environment variables only need to be set for this `gyp_crashpad.py`
+invocation, and need not be permanent.
+
+[subs="verbatim,quotes"]
+----
+$ *cd \~/crashpad/crashpad*
+$ *CC_target=\~/android-ndk-r13_arm64_api21/bin/clang \
+  CXX_target=\~/android-ndk-r13_arm64_api21/bin/clang++ \
+  AR_target=\~/android-ndk-r13_arm64_api21/bin/aarch64-linux-android-ar \
+  NM_target=\~/android-ndk-r13_arm64_api21/bin/aarch64-linux-android-nm \
+  READELF_target=~/android-ndk-r13_arm64_api21/bin/aarch64-linux-android-readelf \
+  python build/gyp_crashpad.py \
+      -DOS=android -Dtarget_arch=arm64 -Dclang=1 \
+      --generator-output=out_android_arm64_api21 -f ninja-android*
+----
+
+Target “triplets” to use for `ar`, `nm`, and `readelf` are:
+
+[width="40%",cols="1,3",frame="topbot"]
+|===
+|`arm` |`arm-linux-androideabi`
+|`arm64` |`aarch64-linux-android`
+|`x86` |`i686-linux-android`
+|`x86_64` |`x86_64-linux-android`
+|===
+
+The port is incomplete, but targets known to be working include `crashpad_util`,
+`crashpad_test`, and `crashpad_test_test`. This list will grow over time. To
+build, direct `ninja` to the specific `out` directory chosen by
+`--generator-output` above.
+
+[subs="verbatim,quotes"]
+----
+$ *ninja -C out_android_arm64_api21/out/Debug crashpad_test_test*
+----
+
 == Testing
 
 Crashpad uses https://github.com/google/googletest/[Google Test] as its
 unit-testing framework, and some tests use
 https://github.com/google/googletest/tree/master/googlemock/[Google Mock] as
 well. Its tests are currently split up into several test executables, each
 dedicated to testing a different component. This may change in the future. After
 a successful build, the test executables will be found at
 `out/Debug/crashpad_*_test`.
 
 [subs="verbatim,quotes"]
 ----
 $ *cd ~/crashpad/crashpad*
 $ *out/Debug/crashpad_minidump_test*
 $ *out/Debug/crashpad_util_test*
 ----
 
 A script is provided to run all of Crashpad’s tests. It accepts a single
 argument that tells it which configuration to test.
 
 [subs="verbatim,quotes"]
 ----
 $ *cd ~/crashpad/crashpad*
 $ *python build/run_tests.py Debug*
 ----
 
+=== Android
+
+To test on Android, use
+https://developer.android.com/studio/command-line/adb.html[ADB (Android Debug
+Bridge)] to `adb push` test executables and test data to a device or emulator,
+then use `adb shell` to get a shell to run the test executables from. ADB is
+part of the https://developer.android.com/sdk/[Android SDK]. Note that it is
+sufficient to install just the command-line tools. The entire Android Studio IDE
+is not necessary to obtain ADB.
+
+This example runs `crashpad_test_test` on a device. This test executable has a
+run-time dependency on a second executable and a test data file, which are also
+transferred to the device prior to running the test.
+
+[subs="verbatim,quotes"]
+----
+$ *cd ~/crashpad/crashpad*
+$ *adb push out_android_arm64_api21/out/Debug/crashpad_test_test /data/local/tmp/*
+[100%] /data/local/tmp/crashpad_test_test
+$ *adb push \
+      out_android_arm64_api21/out/Debug/crashpad_test_test_multiprocess_exec_test_child \
+      /data/local/tmp/*
+[100%] /data/local/tmp/crashpad_test_test_multiprocess_exec_test_child
+$ *adb shell mkdir -p /data/local/tmp/crashpad_test_data_root/test*
+$ *adb push test/paths_test_data_root.txt \
+      /data/local/tmp/crashpad_test_data_root/test/*
+[100%] /data/local/tmp/crashpad_test_data_root/test/paths_test_data_root.txt
+$ *adb shell*
+device:/ $ *cd /data/local/tmp*
+device:/data/local/tmp $ *CRASHPAD_TEST_DATA_ROOT=crashpad_test_data_root \
+                         ./crashpad_test_test*
+----
+
 == Contributing
 
 Crashpad’s contribution process is very similar to
 https://dev.chromium.org/developers/contributing-code[Chromium’s contribution
 process].
 
 === Code Review
 
 A code review must be conducted for every change to Crashpad’s source code. Code
-review is conducted on https://codereview.chromium.org/[Chromium’s Rietveld]
-system, and all code reviews must be sent to an appropriate reviewer, with a Cc
-sent to
+review is conducted on https://chromium-review.googlesource.com/[Chromium’s
+Gerrit] system, and all code reviews must be sent to an appropriate reviewer,
+with a Cc sent to
 https://groups.google.com/a/chromium.org/group/crashpad-dev[crashpad-dev]. The
-`codereview.settings` file specifies this environment to `git-cl`.
+https://chromium.googlesource.com/crashpad/crashpad/+/master/codereview.settings[`codereview.settings`]
+file specifies this environment to `git-cl`.
 
 `git-cl` is part of the
 https://dev.chromium.org/developers/how-tos/depottools[depot_tools]. There’s no
 need to install it separately.
 
 [subs="verbatim,quotes"]
 ----
 $ *cd ~/crashpad/crashpad*
 $ *git checkout -b work_branch origin/master*
 _…do some work…_
 $ *git add …*
 $ *git commit*
 $ *git cl upload*
 ----
 
-Uploading a patch to Rietveld does not automatically request a review. You must
-select a reviewer and mail your request to them (with a Cc to crashpad-dev) from
-the Rietveld issue page after running `git cl upload`. If you have lost track of
-the issue page, `git cl issue` will remind you of its URL. Alternatively, you
-can request review when uploading to Rietveld by using `git cl upload
---send-mail`
+The https://polygerrit.appspot.com/[PolyGerrit interface] to Gerrit, undergoing
+active development, is recommended. To switch from the classic GWT-based Gerrit
+UI to PolyGerrit, click the PolyGerrit link in a Gerrit review page’s footer.
 
-Git branches maintain their association with Rietveld issues, so if you need to
+Uploading a patch to Gerrit does not automatically request a review. You must
+select a reviewer on the Gerrit review page after running `git cl upload`. This
+action notifies your reviewer of the code review request. If you have lost track
+of the review page, `git cl issue` will remind you of its URL. Alternatively,
+you can request review when uploading to Gerrit by using `git cl upload
+--send-mail`.
+
+Git branches maintain their association with Gerrit reviews, so if you need to
 make changes based on review feedback, you can do so on the correct Git branch,
 committing your changes locally with `git commit`. You can then upload a new
 patch set with `git cl upload` and let your reviewer know you’ve addressed the
 feedback.
 
 === Landing Changes
 
-After code review is complete and “LGTM” (“looks good to me”) has been received
-from all reviewers, project members can commit the patch themselves:
+After code review is complete and “Code-Review: +1” has been received from all
+reviewers, project members can commit the patch themselves:
 
 [subs="verbatim,quotes"]
 ----
 $ *cd ~/crashpad/crashpad*
 $ *git checkout work_branch*
 $ *git cl land*
 ----
 
+Alternatively, patches can be committed by clicking the “Submit” button in the
+Gerrit UI.
+
 Crashpad does not currently have a
 https://dev.chromium.org/developers/testing/commit-queue[commit queue], so
-contributors that are not project members will have to ask a project member to
+contributors who are not project members will have to ask a project member to
 commit the patch for them. Project members can commit changes on behalf of
-external contributors by patching the change into a local branch and landing it:
-
-[subs="verbatim,quotes"]
-----
-$ *cd ~/crashpad/crashpad*
-$ *git checkout -b for_external_contributor origin/master*
-$ *git cl patch 12345678*  _# 12345678 is the Rietveld issue number_
-$ *git cl land -c \'External Contributor <external@contributor.org>'*
-----
+external contributors by clicking the “Submit” button in the Gerrit UI.
 
 === External Contributions
 
 Copyright holders must complete the
 https://developers.google.com/open-source/cla/individual[Individual Contributor
 License Agreement] or
 https://developers.google.com/open-source/cla/corporate[Corporate Contributor
 License Agreement] as appropriate before any submission can be accepted, and
 must be listed in the `AUTHORS` file. Contributors may be listed in the
 `CONTRIBUTORS` file.
 
 == Buildbot
 
 The https://build.chromium.org/p/client.crashpad/[Crashpad Buildbot] performs
 automated builds and tests of Crashpad. Before checking out or updating the
 Crashpad source code, and after checking in a new change, it is prudent to check
 the Buildbot to ensure that “the tree is green.”