| commit | fa9fa135289860ecb70eba6fe0c138763675b83c | [log] [tgz] |
|---|---|---|
| author | Erwin Jansen <jansene@google.com> | Wed Mar 26 13:46:41 2025 -0700 |
| committer | Gerrit Code Review <noreply-gerritcodereview@google.com> | Wed Mar 26 13:46:41 2025 -0700 |
| tree | e875b85dc0247e8bdebbb5d2e6b3810de4c9e014 | |
| parent | d721423b32ca829ffe69e1f800a16eb2e0256f89 [diff] | |
| parent | 25872c61baa15dd37e3b33d3773d0d88c322ac01 [diff] |
Merge "feat: Add timestamp to dump crash report" into emu-dev
This repository contains a series of plugins and tools to extend QEMU with android emulator functionality. The android emulator is build using bazel.
You can create a release by running
bazel build --config release //hardware/generic/goldfish/emulator:release
This will produce a zip file for your current architecture. You can unzip this file and launch the emulator. For example on darwin it will produce the following:
bazel build --config release //hardware/generic/goldfish/emulator:release INFO: Analyzed target //hardware/generic/goldfish/emulator:release (0 packages loaded, 0 targets configured). INFO: Found 1 target... Target //hardware/generic/goldfish/emulator:release up-to-date: bazel-bin/hardware/generic/goldfish/emulator/sdk-repo-darwin_aarch64-emulator-developer.zip INFO: Elapsed time: 0.258s, Critical Path: 0.00s INFO: 1 process: 1 internal. INFO: Build completed successfully, 1 total action
The launcher executable is called goldfish.
You can also run the emulator directly from within bazel:
bazel run --config debug //hardware/generic/goldfish/emulator/launcher:goldfish -- --avd V --vnc :8
This will launch the goldfish emulator with avd V and creates a vnc connection on port 5908. You can now attach your favorite debugger to debug any issues.
Note that on linux you will have to set the following source mapping:
$ lldb (lldb) settings set target.source-map /proc/self/cwd /my/bazel/workspace/root
Where /my/bazel/workspace/root points to your bazel workspace root.
We have the following build configurations available:
debug: Unstripped debug build with no optimizations.
release: Optimized stripped release build.
release-assert: Optimized stripped release build with asserts enabled (-UNDEBUG).
asan: Address sanitizer build. AddressSanitizer is a fast memory error detector. The tool can detect the following types of bugs:
ASAN_OPTIONS=detect_stack_use_after_return=1 (already enabled on Linux). Disable with: ASAN_OPTIONS=detect_stack_use_after_return=0.Typical slowdown introduced by AddressSanitizer is 2x.
You can select the configuration by passing the --config {my_config} parameters. For example to create a address sanitizer release you can do:
bazel build --config asan //hardware/generic/goldfish/emulator:release
You can add build flags globally by adding the --copt parameter, for example
bazel build --copt=-funsafe-math-optimizations //hardware/generic/goldfish/emulator:release
Would globablly allow unsafe floating-point optimizations.
AddressSanitizer (ASAN) is a memory error detector that helps identify issues like buffer overflows and use-after-free errors. When using ASAN, ensure the following environment variables are set:
export ASAN_OPTIONS=detect_odr_violation=0
Statically linking glib is causing One Definition Rule (ODR) violations in some of the shared libraries we use. ODR violations occur when the same global object is defined differently in multiple parts of a program. Disabling ODR violation detection prevents ASAN from reporting these errors, which are expected in our current configuration.
You'll need to use a symbolizer to decode the stack frames reported by ASAN. A symbolizer translates memory addresses back into human-readable function names and line numbers, making it easier to understand error reports.
export ASAN_SYMBOLIZER_PATH=/to/clang/llvm-symbolizer
The pixman-1 library, due to complex initialization logic, leaks a few bytes. The set of known (or acceptable) leaks is defined in leak_suppressions.txt
export LSAN_OPTIONS=suppressions=$PWD/leak_suppressions.txt
Use the asan_exports.sh shell script to load this configuration into your shell:
source ./asan_exports.sh
Next you can run the emulator under asan as:
bazel run --config asan //hardware/generic/goldfish/emulator/launcher:goldfish -- --avd V
Note: If you are not seeing memory address translated to stackframes you might have to update the asan_exports.sh shell script to point to the proper symbolizer.
You can find details on getting started here
A JSON Compilation Database is a special file that captures the exact commands used to compile your C++ project. It stores information about include paths, compiler flags, and the location of source files. This data acts as a roadmap, guiding code analysis tools and editors like VSCode and Vim to understand your project's structure, enabling advanced features like:
Various editors and IDE's can consume this file to provide you with an improved developer experience:
YouCompleteMe or coc.nvim can leverage clangd's capabilities for powerful code completion and navigation.In your Bazel workspace, you can generate a JSON Compilation Database using the following command:
bazel run //hardware/generic/goldfish/development/tools/bcc:extract-cc -- //hardware/generic/goldfish/...
This command runs the extract-cc tool located in the specified Bazel package. The -- //hardware/generic/goldfish/... part tells Bazel to generate compilation commands for all C/C++ targets under the //hardware/generic/goldfish directory, including their transitive dependencies. The generated compile_commands.json file will be placed at the root of your Bazel workspace.
Important Considerations
BUILD or BUILD.bazel files require re-running the tool to update the database.compile_commands.json file. Consult your editor's documentation for specific instructions.The following targets might be of interrest if you wish to add new functionality:
//hardware/generic/goldfish/emulator:emulator_unit_tests: This target contains all the test suites that will be run as part of the build. Make sure your tests are added to this suite.//hardware/generic/goldfish/emulator:release: The release target. This constructs the zip file with everything that will be distributed. You will need to modify this if you wish to distribute new files.//hardware/generic/goldfish/emulator/launcher:goldfish: The QEMU launcher. This binary is responsible for configuring the AVD and invoking the qemu emulator with the proper configuration. This is where you configure the drivers, setup the qcow2 images, verify that your system meets the requirements etc..See emulator/plugin/README.MD if you wish to add additional plugins that need to be loaded into QEMU.