1 //===- ArgumentsAdjusters.cpp - Command line arguments adjuster -----------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file contains definitions of classes which implement ArgumentsAdjuster
10 // interface.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "clang/Tooling/ArgumentsAdjusters.h"
15 #include "clang/Basic/LLVM.h"
16 #include "llvm/ADT/STLExtras.h"
17 #include "llvm/ADT/StringRef.h"
18 #include <cstddef>
19 #include <vector>
20 
21 namespace clang {
22 namespace tooling {
23 
24 static StringRef getDriverMode(const CommandLineArguments &Args) {
25   for (const auto &Arg : Args) {
26     StringRef ArgRef = Arg;
27     if (ArgRef.consume_front("--driver-mode=")) {
28       return ArgRef;
29     }
30   }
31   return StringRef();
32 }
33 
34 /// Add -fsyntax-only option and drop options that triggers output generation.
35 ArgumentsAdjuster getClangSyntaxOnlyAdjuster() {
36   return [](const CommandLineArguments &Args, StringRef /*unused*/) {
37     CommandLineArguments AdjustedArgs;
38     bool HasSyntaxOnly = false;
39     constexpr llvm::StringRef OutputCommands[] = {
40         // FIXME: Add other options that generate output.
41         "-save-temps",
42         "--save-temps",
43     };
44     for (size_t i = 0, e = Args.size(); i < e; ++i) {
45       StringRef Arg = Args[i];
46       // Skip output commands.
47       if (llvm::any_of(OutputCommands, [&Arg](llvm::StringRef OutputCommand) {
48             return Arg.startswith(OutputCommand);
49           }))
50         continue;
51 
52       if (!Arg.startswith("-fcolor-diagnostics") &&
53           !Arg.startswith("-fdiagnostics-color"))
54         AdjustedArgs.push_back(Args[i]);
55       // If we strip a color option, make sure we strip any preceeding `-Xclang`
56       // option as well.
57       // FIXME: This should be added to most argument adjusters!
58       else if (!AdjustedArgs.empty() && AdjustedArgs.back() == "-Xclang")
59         AdjustedArgs.pop_back();
60 
61       if (Arg == "-fsyntax-only")
62         HasSyntaxOnly = true;
63     }
64     if (!HasSyntaxOnly)
65       AdjustedArgs =
66           getInsertArgumentAdjuster("-fsyntax-only")(AdjustedArgs, "");
67     return AdjustedArgs;
68   };
69 }
70 
71 ArgumentsAdjuster getClangStripOutputAdjuster() {
72   return [](const CommandLineArguments &Args, StringRef /*unused*/) {
73     CommandLineArguments AdjustedArgs;
74     for (size_t i = 0, e = Args.size(); i < e; ++i) {
75       StringRef Arg = Args[i];
76       if (!Arg.startswith("-o"))
77         AdjustedArgs.push_back(Args[i]);
78 
79       if (Arg == "-o") {
80         // Output is specified as -o foo. Skip the next argument too.
81         ++i;
82       }
83       // Else, the output is specified as -ofoo. Just do nothing.
84     }
85     return AdjustedArgs;
86   };
87 }
88 
89 ArgumentsAdjuster getClangStripDependencyFileAdjuster() {
90   return [](const CommandLineArguments &Args, StringRef /*unused*/) {
91     auto UsingClDriver = (getDriverMode(Args) == "cl");
92 
93     CommandLineArguments AdjustedArgs;
94     for (size_t i = 0, e = Args.size(); i < e; ++i) {
95       StringRef Arg = Args[i];
96 
97       // These flags take an argument: -MX foo. Skip the next argument also.
98       if (!UsingClDriver && (Arg == "-MF" || Arg == "-MT" || Arg == "-MQ")) {
99         ++i;
100         continue;
101       }
102       // When not using the cl driver mode, dependency file generation options
103       // begin with -M. These include -MM, -MF, -MG, -MP, -MT, -MQ, -MD, and
104       // -MMD.
105       if (!UsingClDriver && Arg.startswith("-M"))
106         continue;
107       // Under MSVC's cl driver mode, dependency file generation is controlled
108       // using /showIncludes
109       if (Arg.startswith("/showIncludes") || Arg.startswith("-showIncludes"))
110         continue;
111 
112       AdjustedArgs.push_back(Args[i]);
113     }
114     return AdjustedArgs;
115   };
116 }
117 
118 ArgumentsAdjuster getInsertArgumentAdjuster(const CommandLineArguments &Extra,
119                                             ArgumentInsertPosition Pos) {
120   return [Extra, Pos](const CommandLineArguments &Args, StringRef /*unused*/) {
121     CommandLineArguments Return(Args);
122 
123     CommandLineArguments::iterator I;
124     if (Pos == ArgumentInsertPosition::END) {
125       I = llvm::find(Return, "--");
126     } else {
127       I = Return.begin();
128       ++I; // To leave the program name in place
129     }
130 
131     Return.insert(I, Extra.begin(), Extra.end());
132     return Return;
133   };
134 }
135 
136 ArgumentsAdjuster getInsertArgumentAdjuster(const char *Extra,
137                                             ArgumentInsertPosition Pos) {
138   return getInsertArgumentAdjuster(CommandLineArguments(1, Extra), Pos);
139 }
140 
141 ArgumentsAdjuster combineAdjusters(ArgumentsAdjuster First,
142                                    ArgumentsAdjuster Second) {
143   if (!First)
144     return Second;
145   if (!Second)
146     return First;
147   return [First, Second](const CommandLineArguments &Args, StringRef File) {
148     return Second(First(Args, File), File);
149   };
150 }
151 
152 ArgumentsAdjuster getStripPluginsAdjuster() {
153   return [](const CommandLineArguments &Args, StringRef /*unused*/) {
154     CommandLineArguments AdjustedArgs;
155     for (size_t I = 0, E = Args.size(); I != E; I++) {
156       // According to https://clang.llvm.org/docs/ClangPlugins.html
157       // plugin arguments are in the form:
158       // -Xclang {-load, -plugin, -plugin-arg-<plugin-name>, -add-plugin}
159       // -Xclang <arbitrary-argument>
160       if (I + 4 < E && Args[I] == "-Xclang" &&
161           (Args[I + 1] == "-load" || Args[I + 1] == "-plugin" ||
162            llvm::StringRef(Args[I + 1]).startswith("-plugin-arg-") ||
163            Args[I + 1] == "-add-plugin") &&
164           Args[I + 2] == "-Xclang") {
165         I += 3;
166         continue;
167       }
168       AdjustedArgs.push_back(Args[I]);
169     }
170     return AdjustedArgs;
171   };
172 }
173 
174 } // end namespace tooling
175 } // end namespace clang
176