1// Copyright 2016 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 cc
16
17import (
18	"regexp"
19	"strings"
20
21	"github.com/google/blueprint/proptools"
22
23	"android/soong/android"
24	"android/soong/cc/config"
25)
26
27type TidyProperties struct {
28	// whether to run clang-tidy over C-like sources.
29	Tidy *bool
30
31	// Extra flags to pass to clang-tidy
32	Tidy_flags []string
33
34	// Extra checks to enable or disable in clang-tidy
35	Tidy_checks []string
36
37	// Checks that should be treated as errors.
38	Tidy_checks_as_errors []string
39}
40
41type tidyFeature struct {
42	Properties TidyProperties
43}
44
45var quotedFlagRegexp, _ = regexp.Compile(`^-?-[^=]+=('|").*('|")$`)
46
47// When passing flag -name=value, if user add quotes around 'value',
48// the quotation marks will be preserved by NinjaAndShellEscapeList
49// and the 'value' string with quotes won't work like the intended value.
50// So here we report an error if -*='*' is found.
51func checkNinjaAndShellEscapeList(ctx ModuleContext, prop string, slice []string) []string {
52	for _, s := range slice {
53		if quotedFlagRegexp.MatchString(s) {
54			ctx.PropertyErrorf(prop, "Extra quotes in: %s", s)
55		}
56	}
57	return proptools.NinjaAndShellEscapeList(slice)
58}
59
60func (tidy *tidyFeature) props() []interface{} {
61	return []interface{}{&tidy.Properties}
62}
63
64func (tidy *tidyFeature) begin(ctx BaseModuleContext) {
65}
66
67func (tidy *tidyFeature) deps(ctx DepsContext, deps Deps) Deps {
68	return deps
69}
70
71func (tidy *tidyFeature) flags(ctx ModuleContext, flags Flags) Flags {
72	CheckBadTidyFlags(ctx, "tidy_flags", tidy.Properties.Tidy_flags)
73	CheckBadTidyChecks(ctx, "tidy_checks", tidy.Properties.Tidy_checks)
74
75	// Check if tidy is explicitly disabled for this module
76	if tidy.Properties.Tidy != nil && !*tidy.Properties.Tidy {
77		return flags
78	}
79
80	// If not explicitly set, check the global tidy flag
81	if tidy.Properties.Tidy == nil && !ctx.Config().ClangTidy() {
82		return flags
83	}
84
85	flags.Tidy = true
86
87	// Add global WITH_TIDY_FLAGS and local tidy_flags.
88	withTidyFlags := ctx.Config().Getenv("WITH_TIDY_FLAGS")
89	if len(withTidyFlags) > 0 {
90		flags.TidyFlags = append(flags.TidyFlags, withTidyFlags)
91	}
92	esc := checkNinjaAndShellEscapeList
93	flags.TidyFlags = append(flags.TidyFlags, esc(ctx, "tidy_flags", tidy.Properties.Tidy_flags)...)
94	// If TidyFlags does not contain -header-filter, add default header filter.
95	// Find the substring because the flag could also appear as --header-filter=...
96	// and with or without single or double quotes.
97	if !android.SubstringInList(flags.TidyFlags, "-header-filter=") {
98		defaultDirs := ctx.Config().Getenv("DEFAULT_TIDY_HEADER_DIRS")
99		headerFilter := "-header-filter="
100		if defaultDirs == "" {
101			headerFilter += ctx.ModuleDir() + "/"
102		} else {
103			headerFilter += "\"(" + ctx.ModuleDir() + "/|" + defaultDirs + ")\""
104		}
105		flags.TidyFlags = append(flags.TidyFlags, headerFilter)
106	}
107
108	// If clang-tidy is not enabled globally, add the -quiet flag.
109	if !ctx.Config().ClangTidy() {
110		flags.TidyFlags = append(flags.TidyFlags, "-quiet")
111		flags.TidyFlags = append(flags.TidyFlags, "-extra-arg-before=-fno-caret-diagnostics")
112	}
113
114	extraArgFlags := []string{
115		// We might be using the static analyzer through clang tidy.
116		// https://bugs.llvm.org/show_bug.cgi?id=32914
117		"-D__clang_analyzer__",
118
119		// A recent change in clang-tidy (r328258) enabled destructor inlining, which
120		// appears to cause a number of false positives. Until that's resolved, this turns
121		// off the effects of r328258.
122		// https://bugs.llvm.org/show_bug.cgi?id=37459
123		"-Xclang", "-analyzer-config", "-Xclang", "c++-temp-dtor-inlining=false",
124	}
125
126	for _, f := range extraArgFlags {
127		flags.TidyFlags = append(flags.TidyFlags, "-extra-arg-before="+f)
128	}
129
130	tidyChecks := "-checks="
131	if checks := ctx.Config().TidyChecks(); len(checks) > 0 {
132		tidyChecks += checks
133	} else {
134		tidyChecks += config.TidyChecksForDir(ctx.ModuleDir())
135	}
136	if len(tidy.Properties.Tidy_checks) > 0 {
137		tidyChecks = tidyChecks + "," + strings.Join(esc(ctx, "tidy_checks",
138			config.ClangRewriteTidyChecks(tidy.Properties.Tidy_checks)), ",")
139	}
140	if ctx.Windows() {
141		// https://b.corp.google.com/issues/120614316
142		// mingw32 has cert-dcl16-c warning in NO_ERROR,
143		// which is used in many Android files.
144		tidyChecks = tidyChecks + ",-cert-dcl16-c"
145	}
146	// https://b.corp.google.com/issues/153464409
147	// many local projects enable cert-* checks, which
148	// trigger bugprone-reserved-identifier.
149	tidyChecks = tidyChecks + ",-bugprone-reserved-identifier*,-cert-dcl51-cpp,-cert-dcl37-c"
150	// http://b/153757728
151	tidyChecks = tidyChecks + ",-readability-qualified-auto"
152	// http://b/155034563
153	tidyChecks = tidyChecks + ",-bugprone-signed-char-misuse"
154	// http://b/155034972
155	tidyChecks = tidyChecks + ",-bugprone-branch-clone"
156	flags.TidyFlags = append(flags.TidyFlags, tidyChecks)
157
158	if ctx.Config().IsEnvTrue("WITH_TIDY") {
159		// WITH_TIDY=1 enables clang-tidy globally. There could be many unexpected
160		// warnings from new checks and many local tidy_checks_as_errors and
161		// -warnings-as-errors can break a global build.
162		// So allow all clang-tidy warnings.
163		inserted := false
164		for i, s := range flags.TidyFlags {
165			if strings.Contains(s, "-warnings-as-errors=") {
166				// clang-tidy accepts only one -warnings-as-errors
167				// replace the old one
168				re := regexp.MustCompile(`'?-?-warnings-as-errors=[^ ]* *`)
169				newFlag := re.ReplaceAllString(s, "")
170				if newFlag == "" {
171					flags.TidyFlags[i] = "-warnings-as-errors=-*"
172				} else {
173					flags.TidyFlags[i] = newFlag + " -warnings-as-errors=-*"
174				}
175				inserted = true
176				break
177			}
178		}
179		if !inserted {
180			flags.TidyFlags = append(flags.TidyFlags, "-warnings-as-errors=-*")
181		}
182	} else if len(tidy.Properties.Tidy_checks_as_errors) > 0 {
183		tidyChecksAsErrors := "-warnings-as-errors=" + strings.Join(esc(ctx, "tidy_checks_as_errors", tidy.Properties.Tidy_checks_as_errors), ",")
184		flags.TidyFlags = append(flags.TidyFlags, tidyChecksAsErrors)
185	}
186	return flags
187}
188