1// Copyright 2019 Google Inc. All rights reserved.
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15package java
16
17import (
18	"strings"
19
20	"android/soong/android"
21)
22
23func init() {
24	RegisterHiddenApiSingletonComponents(android.InitRegistrationContext)
25}
26
27func RegisterHiddenApiSingletonComponents(ctx android.RegistrationContext) {
28	ctx.RegisterSingletonType("hiddenapi", hiddenAPISingletonFactory)
29}
30
31var PrepareForTestWithHiddenApiBuildComponents = android.FixtureRegisterWithContext(RegisterHiddenApiSingletonComponents)
32
33type hiddenAPISingletonPathsStruct struct {
34	// The path to the CSV file that contains the flags that will be encoded into the dex boot jars.
35	//
36	// It is created by the generate_hiddenapi_lists.py tool that is passed the stubFlags along with
37	// a number of additional files that are used to augment the information in the stubFlags with
38	// manually curated data.
39	flags android.OutputPath
40
41	// The path to the CSV index file that contains mappings from Java signature to source location
42	// information for all Java elements annotated with the UnsupportedAppUsage annotation in the
43	// source of all the boot jars.
44	//
45	// It is created by the merge_csv tool which merges all the hiddenAPI.indexCSVPath files that have
46	// been created by the rest of the build. That includes the index files generated for
47	// <x>-hiddenapi modules.
48	index android.OutputPath
49
50	// The path to the CSV metadata file that contains mappings from Java signature to the value of
51	// properties specified on UnsupportedAppUsage annotations in the source of all the boot jars.
52	//
53	// It is created by the merge_csv tool which merges all the hiddenAPI.metadataCSVPath files that
54	// have been created by the rest of the build. That includes the metadata files generated for
55	// <x>-hiddenapi modules.
56	metadata android.OutputPath
57
58	// The path to the CSV metadata file that contains mappings from Java signature to flags obtained
59	// from the public, system and test API stubs.
60	//
61	// This is created by the hiddenapi tool which is given dex files for the public, system and test
62	// API stubs (including product specific stubs) along with dex boot jars, so does not include
63	// <x>-hiddenapi modules. For each API surface (i.e. public, system, test) it records which
64	// members in the dex boot jars match a member in the dex stub jars for that API surface and then
65	// outputs a file containing the signatures of all members in the dex boot jars along with the
66	// flags that indicate which API surface it belongs, if any.
67	//
68	// e.g. a dex member that matches a member in the public dex stubs would have flags
69	// "public-api,system-api,test-api" set (as system and test are both supersets of public). A dex
70	// member that didn't match a member in any of the dex stubs is still output it just has an empty
71	// set of flags.
72	//
73	// The notion of matching is quite complex, it is not restricted to just exact matching but also
74	// follows the Java inheritance rules. e.g. if a method is public then all overriding/implementing
75	// methods are also public. If an interface method is public and a class inherits an
76	// implementation of that method from a super class then that super class method is also public.
77	// That ensures that any method that can be called directly by an App through a public method is
78	// visible to that App.
79	//
80	// Propagating the visibility of members across the inheritance hierarchy at build time will cause
81	// problems when modularizing and unbundling as it that propagation can cross module boundaries.
82	// e.g. Say that a private framework class implements a public interface and inherits an
83	// implementation of one of its methods from a core platform ART class. In that case the ART
84	// implementation method needs to be marked as public which requires the build to have access to
85	// the framework implementation classes at build time. The work to rectify this is being tracked
86	// at http://b/178693149.
87	//
88	// This file (or at least those items marked as being in the public-api) is used by hiddenapi when
89	// creating the metadata and flags for the individual modules in order to perform consistency
90	// checks and filter out bridge methods that are part of the public API. The latter relies on the
91	// propagation of visibility across the inheritance hierarchy.
92	stubFlags android.OutputPath
93}
94
95var hiddenAPISingletonPathsKey = android.NewOnceKey("hiddenAPISingletonPathsKey")
96
97// hiddenAPISingletonPaths creates all the paths for singleton files the first time it is called, which may be
98// from a ModuleContext that needs to reference a file that will be created by a singleton rule that hasn't
99// yet been created.
100func hiddenAPISingletonPaths(ctx android.PathContext) hiddenAPISingletonPathsStruct {
101	return ctx.Config().Once(hiddenAPISingletonPathsKey, func() interface{} {
102		// Make the paths relative to the out/soong/hiddenapi directory instead of to the out/soong/
103		// directory. This ensures that if they are used as java_resources they do not end up in a
104		// hiddenapi directory in the resulting APK.
105		hiddenapiDir := android.PathForOutput(ctx, "hiddenapi")
106		return hiddenAPISingletonPathsStruct{
107			flags:     hiddenapiDir.Join(ctx, "hiddenapi-flags.csv"),
108			index:     hiddenapiDir.Join(ctx, "hiddenapi-index.csv"),
109			metadata:  hiddenapiDir.Join(ctx, "hiddenapi-unsupported.csv"),
110			stubFlags: hiddenapiDir.Join(ctx, "hiddenapi-stub-flags.txt"),
111		}
112	}).(hiddenAPISingletonPathsStruct)
113}
114
115func hiddenAPISingletonFactory() android.Singleton {
116	return &hiddenAPISingleton{}
117}
118
119type hiddenAPISingleton struct {
120}
121
122// hiddenAPI singleton rules
123func (h *hiddenAPISingleton) GenerateBuildActions(ctx android.SingletonContext) {
124	// Don't run any hiddenapi rules if UNSAFE_DISABLE_HIDDENAPI_FLAGS=true
125	if ctx.Config().IsEnvTrue("UNSAFE_DISABLE_HIDDENAPI_FLAGS") {
126		return
127	}
128
129	// If there is a prebuilt hiddenapi dir, generate rules to use the
130	// files within. Generally, we build the hiddenapi files from source
131	// during the build, ensuring consistency. It's possible, in a split
132	// build (framework and vendor) scenario, for the vendor build to use
133	// prebuilt hiddenapi files from the framework build. In this scenario,
134	// the framework and vendor builds must use the same source to ensure
135	// consistency.
136
137	if ctx.Config().PrebuiltHiddenApiDir(ctx) != "" {
138		prebuiltFlagsRule(ctx)
139		prebuiltIndexRule(ctx)
140		return
141	}
142}
143
144// Checks to see whether the supplied module variant is in the list of boot jars.
145//
146// TODO(b/179354495): Avoid having to perform this type of check.
147func isModuleInConfiguredList(ctx android.BaseModuleContext, module android.Module, configuredBootJars android.ConfiguredJarList) bool {
148	name := ctx.OtherModuleName(module)
149
150	// Strip a prebuilt_ prefix so that this can match a prebuilt module that has not been renamed.
151	name = android.RemoveOptionalPrebuiltPrefix(name)
152
153	// Ignore any module that is not listed in the boot image configuration.
154	index := configuredBootJars.IndexOfJar(name)
155	if index == -1 {
156		return false
157	}
158
159	// It is an error if the module is not an ApexModule.
160	if _, ok := module.(android.ApexModule); !ok {
161		ctx.ModuleErrorf("%s is configured in boot jars but does not support being added to an apex", ctx.OtherModuleName(module))
162		return false
163	}
164
165	apexInfo := ctx.OtherModuleProvider(module, android.ApexInfoProvider).(android.ApexInfo)
166
167	// Now match the apex part of the boot image configuration.
168	requiredApex := configuredBootJars.Apex(index)
169	if requiredApex == "platform" || requiredApex == "system_ext" {
170		if len(apexInfo.InApexVariants) != 0 {
171			// A platform variant is required but this is for an apex so ignore it.
172			return false
173		}
174	} else if !apexInfo.InApexVariant(requiredApex) {
175		// An apex variant for a specific apex is required but this is the wrong apex.
176		return false
177	}
178
179	return true
180}
181
182func prebuiltFlagsRule(ctx android.SingletonContext) {
183	outputPath := hiddenAPISingletonPaths(ctx).flags
184	inputPath := android.PathForSource(ctx, ctx.Config().PrebuiltHiddenApiDir(ctx), "hiddenapi-flags.csv")
185
186	ctx.Build(pctx, android.BuildParams{
187		Rule:   android.Cp,
188		Output: outputPath,
189		Input:  inputPath,
190	})
191}
192
193func prebuiltIndexRule(ctx android.SingletonContext) {
194	outputPath := hiddenAPISingletonPaths(ctx).index
195	inputPath := android.PathForSource(ctx, ctx.Config().PrebuiltHiddenApiDir(ctx), "hiddenapi-index.csv")
196
197	ctx.Build(pctx, android.BuildParams{
198		Rule:   android.Cp,
199		Output: outputPath,
200		Input:  inputPath,
201	})
202}
203
204// tempPathForRestat creates a path of the same type as the supplied type but with a name of
205// <path>.tmp.
206//
207// e.g. If path is an OutputPath for out/soong/hiddenapi/hiddenapi-flags.csv then this will return
208// an OutputPath for out/soong/hiddenapi/hiddenapi-flags.csv.tmp
209func tempPathForRestat(ctx android.PathContext, path android.WritablePath) android.WritablePath {
210	extWithoutLeadingDot := strings.TrimPrefix(path.Ext(), ".")
211	return path.ReplaceExtension(ctx, extWithoutLeadingDot+".tmp")
212}
213
214// commitChangeForRestat adds a command to a rule that updates outputPath from tempPath if they are different.  It
215// also marks the rule as restat and marks the tempPath as a temporary file that should not be considered an output of
216// the rule.
217func commitChangeForRestat(rule *android.RuleBuilder, tempPath, outputPath android.WritablePath) {
218	rule.Restat()
219	rule.Temporary(tempPath)
220	rule.Command().
221		Text("(").
222		Text("if").
223		Text("cmp -s").Input(tempPath).Output(outputPath).Text(";").
224		Text("then").
225		Text("rm").Input(tempPath).Text(";").
226		Text("else").
227		Text("mv").Input(tempPath).Output(outputPath).Text(";").
228		Text("fi").
229		Text(")")
230}
231