soong_ui kati.go: write more comments.
This CL also removes --warn_real_to_phony and --warn_phony_looks_real,
since --werror_real_to_phony and --wrror_phony_looks_real are already
specified.
Test: treehugger
Bug: 173474588
Change-Id: Icbb0f53182d1b912c62f8044f52bb79d985bf868
diff --git a/ui/build/kati.go b/ui/build/kati.go
index f6c0f52..06ec646 100644
--- a/ui/build/kati.go
+++ b/ui/build/kati.go
@@ -33,12 +33,18 @@
const katiCleanspecSuffix = "-cleanspec"
const katiPackageSuffix = "-package"
-// genKatiSuffix creates a suffix for kati-generated files so that we can cache
-// them based on their inputs. So this should encode all common changes to Kati
-// inputs. Currently that includes the TARGET_PRODUCT, kati-processed command
-// line arguments, and the directories specified by mm/mmm.
+// genKatiSuffix creates a filename suffix for kati-generated files so that we
+// can cache them based on their inputs. Such files include the generated Ninja
+// files and env.sh environment variable setup files.
+//
+// The filename suffix should encode all common changes to Kati inputs.
+// Currently that includes the TARGET_PRODUCT and kati-processed command line
+// arguments.
func genKatiSuffix(ctx Context, config Config) {
+ // Construct the base suffix.
katiSuffix := "-" + config.TargetProduct()
+
+ // Append kati arguments to the suffix.
if args := config.KatiArgs(); len(args) > 0 {
katiSuffix += "-" + spaceSlashReplacer.Replace(strings.Join(args, "_"))
}
@@ -60,51 +66,101 @@
}
}
+// Base function to construct and run the Kati command line with additional
+// arguments, and a custom function closure to mutate the environment Kati runs
+// in.
func runKati(ctx Context, config Config, extraSuffix string, args []string, envFunc func(*Environment)) {
executable := config.PrebuiltBuildTool("ckati")
+ // cKati arguments.
args = append([]string{
+ // Instead of executing commands directly, generate a Ninja file.
"--ninja",
+ // Generate Ninja files in the output directory.
"--ninja_dir=" + config.OutDir(),
+ // Filename suffix of the generated Ninja file.
"--ninja_suffix=" + config.KatiSuffix() + extraSuffix,
+ // Remove common parts at the beginning of a Ninja file, like build_dir,
+ // local_pool and _kati_always_build_. Allows Kati to be run multiple
+ // times, with generated Ninja files combined in a single invocation
+ // using 'include'.
"--no_ninja_prelude",
+ // Support declaring phony outputs in AOSP Ninja.
"--use_ninja_phony_output",
+ // Support declaring symlink outputs in AOSP Ninja.
"--use_ninja_symlink_outputs",
+ // Regenerate the Ninja file if environment inputs have changed. e.g.
+ // CLI flags, .mk file timestamps, env vars, $(wildcard ..) and some
+ // $(shell ..) results.
"--regen",
+ // Skip '-include' directives starting with the specified path. Used to
+ // ignore generated .mk files.
"--ignore_optional_include=" + filepath.Join(config.OutDir(), "%.P"),
+ // Detect the use of $(shell echo ...).
"--detect_android_echo",
+ // Colorful ANSI-based warning and error messages.
"--color_warnings",
+ // Generate all targets, not just the top level requested ones.
"--gen_all_targets",
+ // Use the built-in emulator of GNU find for better file finding
+ // performance. Used with $(shell find ...).
"--use_find_emulator",
+ // Fail when the find emulator encounters problems.
"--werror_find_emulator",
+ // Do not provide any built-in rules.
"--no_builtin_rules",
+ // Fail when suffix rules are used.
"--werror_suffix_rules",
- "--warn_real_to_phony",
- "--warn_phony_looks_real",
+ // Fail when a real target depends on a phony target.
"--werror_real_to_phony",
- "--werror_phony_looks_real",
- "--werror_writable",
+ // Makes real_to_phony checks assume that any top-level or leaf
+ // dependencies that does *not* have a '/' in it is a phony target.
"--top_level_phony",
+ // Fail when a phony target contains slashes.
+ "--werror_phony_looks_real",
+ // Fail when writing to a read-only directory.
+ "--werror_writable",
+ // Print Kati's internal statistics, such as the number of variables,
+ // implicit/explicit/suffix rules, and so on.
"--kati_stats",
}, args...)
+ // Generate a minimal Ninja file.
+ //
+ // Used for build_test and multiproduct_kati, which runs Kati several
+ // hundred times for different configurations to test file generation logic.
+ // These can result in generating Ninja files reaching ~1GB or more,
+ // resulting in ~hundreds of GBs of writes.
+ //
+ // Since we don't care about executing the Ninja files in these test cases,
+ // generating the Ninja file content wastes time, so skip writing any
+ // information out with --empty_ninja_file.
+ //
+ // From https://github.com/google/kati/commit/87b8da7af2c8bea28b1d8ab17679453d859f96e5
if config.Environment().IsEnvTrue("EMPTY_NINJA_FILE") {
args = append(args, "--empty_ninja_file")
}
+ // Apply 'local_pool' to to all rules that don't specify a pool.
if config.UseRemoteBuild() {
args = append(args, "--default_pool=local_pool")
}
cmd := Command(ctx, config, "ckati", executable, args...)
+
+ // Set up the nsjail sandbox.
cmd.Sandbox = katiSandbox
+
+ // Set up stdout and stderr.
pipe, err := cmd.StdoutPipe()
if err != nil {
ctx.Fatalln("Error getting output pipe for ckati:", err)
}
cmd.Stderr = cmd.Stdout
+ // Apply the caller's function closure to mutate the environment variables.
envFunc(cmd.Environment)
+ // Pass on various build environment metadata to Kati.
if _, ok := cmd.Environment.Get("BUILD_USERNAME"); !ok {
username := "unknown"
if u, err := user.Current(); err == nil {
@@ -125,6 +181,8 @@
}
cmd.StartOrFatal()
+ // Set up the ToolStatus command line reader for Kati for a consistent UI
+ // for the user.
status.KatiReader(ctx.Status.StartTool(), pipe)
cmd.WaitOrFatal()
}
@@ -134,35 +192,57 @@
defer ctx.EndTrace()
args := []string{
+ // Mark the output directory as writable.
"--writable", config.OutDir() + "/",
+ // Fail when encountering implicit rules. e.g.
+ // %.foo: %.bar
+ // cp $< $@
"--werror_implicit_rules",
+ // Entry point for the Kati Ninja file generation.
"-f", "build/make/core/main.mk",
}
if !config.BuildBrokenDupRules() {
+ // Fail when redefining / duplicating a target.
args = append(args, "--werror_overriding_commands")
}
args = append(args, config.KatiArgs()...)
args = append(args,
+ // Location of the Make vars .mk file generated by Soong.
"SOONG_MAKEVARS_MK="+config.SoongMakeVarsMk(),
+ // Location of the Android.mk file generated by Soong. This
+ // file contains Soong modules represented as Kati modules,
+ // allowing Kati modules to depend on Soong modules.
"SOONG_ANDROID_MK="+config.SoongAndroidMk(),
+ // Directory containing outputs for the target device.
"TARGET_DEVICE_DIR="+config.TargetDeviceDir(),
+ // Directory containing .mk files for packaging purposes, such as
+ // the dist.mk file, containing dist-for-goals data.
"KATI_PACKAGE_MK_DIR="+config.KatiPackageMkDir())
runKati(ctx, config, katiBuildSuffix, args, func(env *Environment) {})
+ // compress and dist the main build ninja file.
distGzipFile(ctx, config, config.KatiBuildNinjaFile())
+ // Cleanup steps.
cleanCopyHeaders(ctx, config)
cleanOldInstalledFiles(ctx, config)
}
+// Clean out obsolete header files on the disk that were *not copied* during the
+// build with BUILD_COPY_HEADERS and LOCAL_COPY_HEADERS.
+//
+// These should be increasingly uncommon, as it's a deprecated feature and there
+// isn't an equivalent feature in Soong.
func cleanCopyHeaders(ctx Context, config Config) {
ctx.BeginTrace("clean", "clean copy headers")
defer ctx.EndTrace()
+ // Read and parse the list of copied headers from a file in the product
+ // output directory.
data, err := ioutil.ReadFile(filepath.Join(config.ProductOut(), ".copied_headers_list"))
if err != nil {
if os.IsNotExist(err) {
@@ -178,6 +258,8 @@
headerDir := headers[0]
headers = headers[1:]
+ // Walk the tree and remove any headers that are not in the list of copied
+ // headers in the current build.
filepath.Walk(headerDir,
func(path string, info os.FileInfo, err error) error {
if err != nil {
@@ -196,6 +278,8 @@
})
}
+// Clean out any previously installed files from the disk that are not installed
+// in the current build.
func cleanOldInstalledFiles(ctx Context, config Config) {
ctx.BeginTrace("clean", "clean old installed files")
defer ctx.EndTrace()
@@ -213,18 +297,27 @@
cleanOldFiles(ctx, config.HostOut(), ".installable_test_files")
}
+// Generate the Ninja file containing the packaging command lines for the dist
+// dir.
func runKatiPackage(ctx Context, config Config) {
ctx.BeginTrace(metrics.RunKati, "kati package")
defer ctx.EndTrace()
args := []string{
+ // Mark the dist dir as writable.
"--writable", config.DistDir() + "/",
+ // Fail when encountering implicit rules. e.g.
"--werror_implicit_rules",
+ // Fail when redefining / duplicating a target.
"--werror_overriding_commands",
+ // Entry point.
"-f", "build/make/packaging/main.mk",
+ // Directory containing .mk files for packaging purposes, such as
+ // the dist.mk file, containing dist-for-goals data.
"KATI_PACKAGE_MK_DIR=" + config.KatiPackageMkDir(),
}
+ // Run Kati against a restricted set of environment variables.
runKati(ctx, config, katiPackageSuffix, args, func(env *Environment) {
env.Allow([]string{
// Some generic basics
@@ -251,16 +344,21 @@
}
})
+ // Compress and dist the packaging Ninja file.
distGzipFile(ctx, config, config.KatiPackageNinjaFile())
}
+// Run Kati on the cleanspec files to clean the build.
func runKatiCleanSpec(ctx Context, config Config) {
ctx.BeginTrace(metrics.RunKati, "kati cleanspec")
defer ctx.EndTrace()
runKati(ctx, config, katiCleanspecSuffix, []string{
+ // Fail when encountering implicit rules. e.g.
"--werror_implicit_rules",
+ // Fail when redefining / duplicating a target.
"--werror_overriding_commands",
+ // Entry point.
"-f", "build/make/core/cleanbuild.mk",
"SOONG_MAKEVARS_MK=" + config.SoongMakeVarsMk(),
"TARGET_DEVICE_DIR=" + config.TargetDeviceDir(),