1 //===--- Job.cpp - Command to Execute -------------------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "clang/Driver/Driver.h"
11 #include "clang/Driver/DriverDiagnostic.h"
12 #include "clang/Driver/Job.h"
13 #include "clang/Driver/Tool.h"
14 #include "clang/Driver/ToolChain.h"
15 #include "llvm/ADT/ArrayRef.h"
16 #include "llvm/ADT/STLExtras.h"
17 #include "llvm/ADT/StringRef.h"
18 #include "llvm/ADT/StringSet.h"
19 #include "llvm/ADT/StringSwitch.h"
20 #include "llvm/Support/Program.h"
21 #include "llvm/Support/raw_ostream.h"
22 #include <cassert>
23 using namespace clang::driver;
24 using llvm::raw_ostream;
25 using llvm::StringRef;
26 using llvm::ArrayRef;
27 
~Job()28 Job::~Job() {}
29 
Command(const Action & _Source,const Tool & _Creator,const char * _Executable,const ArgStringList & _Arguments)30 Command::Command(const Action &_Source, const Tool &_Creator,
31                  const char *_Executable,
32                  const ArgStringList &_Arguments)
33     : Job(CommandClass), Source(_Source), Creator(_Creator),
34       Executable(_Executable), Arguments(_Arguments),
35       ResponseFile(nullptr) {}
36 
skipArgs(const char * Flag,bool HaveCrashVFS)37 static int skipArgs(const char *Flag, bool HaveCrashVFS) {
38   // These flags are all of the form -Flag <Arg> and are treated as two
39   // arguments.  Therefore, we need to skip the flag and the next argument.
40   bool Res = llvm::StringSwitch<bool>(Flag)
41     .Cases("-I", "-MF", "-MT", "-MQ", true)
42     .Cases("-o", "-coverage-file", "-dependency-file", true)
43     .Cases("-fdebug-compilation-dir", "-idirafter", true)
44     .Cases("-include", "-include-pch", "-internal-isystem", true)
45     .Cases("-internal-externc-isystem", "-iprefix", "-iwithprefix", true)
46     .Cases("-iwithprefixbefore", "-isystem", "-iquote", true)
47     .Cases("-resource-dir", "-serialize-diagnostic-file", true)
48     .Cases("-dwarf-debug-flags", "-ivfsoverlay", true)
49     // Some include flags shouldn't be skipped if we have a crash VFS
50     .Case("-isysroot", !HaveCrashVFS)
51     .Default(false);
52 
53   // Match found.
54   if (Res)
55     return 2;
56 
57   // The remaining flags are treated as a single argument.
58 
59   // These flags are all of the form -Flag and have no second argument.
60   Res = llvm::StringSwitch<bool>(Flag)
61     .Cases("-M", "-MM", "-MG", "-MP", "-MD", true)
62     .Case("-MMD", true)
63     .Default(false);
64 
65   // Match found.
66   if (Res)
67     return 1;
68 
69   // These flags are treated as a single argument (e.g., -F<Dir>).
70   StringRef FlagRef(Flag);
71   if (FlagRef.startswith("-F") || FlagRef.startswith("-I") ||
72       FlagRef.startswith("-fmodules-cache-path="))
73     return 1;
74 
75   return 0;
76 }
77 
PrintArg(raw_ostream & OS,const char * Arg,bool Quote)78 static void PrintArg(raw_ostream &OS, const char *Arg, bool Quote) {
79   const bool Escape = std::strpbrk(Arg, "\"\\$");
80 
81   if (!Quote && !Escape) {
82     OS << Arg;
83     return;
84   }
85 
86   // Quote and escape. This isn't really complete, but good enough.
87   OS << '"';
88   while (const char c = *Arg++) {
89     if (c == '"' || c == '\\' || c == '$')
90       OS << '\\';
91     OS << c;
92   }
93   OS << '"';
94 }
95 
writeResponseFile(raw_ostream & OS) const96 void Command::writeResponseFile(raw_ostream &OS) const {
97   // In a file list, we only write the set of inputs to the response file
98   if (Creator.getResponseFilesSupport() == Tool::RF_FileList) {
99     for (const char *Arg : InputFileList) {
100       OS << Arg << '\n';
101     }
102     return;
103   }
104 
105   // In regular response files, we send all arguments to the response file
106   for (const char *Arg : Arguments) {
107     OS << '"';
108 
109     for (; *Arg != '\0'; Arg++) {
110       if (*Arg == '\"' || *Arg == '\\') {
111         OS << '\\';
112       }
113       OS << *Arg;
114     }
115 
116     OS << "\" ";
117   }
118 }
119 
buildArgvForResponseFile(llvm::SmallVectorImpl<const char * > & Out) const120 void Command::buildArgvForResponseFile(
121     llvm::SmallVectorImpl<const char *> &Out) const {
122   // When not a file list, all arguments are sent to the response file.
123   // This leaves us to set the argv to a single parameter, requesting the tool
124   // to read the response file.
125   if (Creator.getResponseFilesSupport() != Tool::RF_FileList) {
126     Out.push_back(Executable);
127     Out.push_back(ResponseFileFlag.c_str());
128     return;
129   }
130 
131   llvm::StringSet<> Inputs;
132   for (const char *InputName : InputFileList)
133     Inputs.insert(InputName);
134   Out.push_back(Executable);
135   // In a file list, build args vector ignoring parameters that will go in the
136   // response file (elements of the InputFileList vector)
137   bool FirstInput = true;
138   for (const char *Arg : Arguments) {
139     if (Inputs.count(Arg) == 0) {
140       Out.push_back(Arg);
141     } else if (FirstInput) {
142       FirstInput = false;
143       Out.push_back(Creator.getResponseFileFlag());
144       Out.push_back(ResponseFile);
145     }
146   }
147 }
148 
Print(raw_ostream & OS,const char * Terminator,bool Quote,CrashReportInfo * CrashInfo) const149 void Command::Print(raw_ostream &OS, const char *Terminator, bool Quote,
150                     CrashReportInfo *CrashInfo) const {
151   // Always quote the exe.
152   OS << ' ';
153   PrintArg(OS, Executable, /*Quote=*/true);
154 
155   llvm::ArrayRef<const char *> Args = Arguments;
156   llvm::SmallVector<const char *, 128> ArgsRespFile;
157   if (ResponseFile != nullptr) {
158     buildArgvForResponseFile(ArgsRespFile);
159     Args = ArrayRef<const char *>(ArgsRespFile).slice(1); // no executable name
160   }
161 
162   StringRef MainFilename;
163   // We'll need the argument to -main-file-name to find the input file name.
164   if (CrashInfo)
165     for (size_t I = 0, E = Args.size(); I + 1 < E; ++I)
166       if (StringRef(Args[I]).equals("-main-file-name"))
167         MainFilename = Args[I + 1];
168 
169   bool HaveCrashVFS = CrashInfo && !CrashInfo->VFSPath.empty();
170   for (size_t i = 0, e = Args.size(); i < e; ++i) {
171     const char *const Arg = Args[i];
172 
173     if (CrashInfo) {
174       if (int Skip = skipArgs(Arg, HaveCrashVFS)) {
175         i += Skip - 1;
176         continue;
177       } else if (llvm::sys::path::filename(Arg) == MainFilename &&
178                  (i == 0 || StringRef(Args[i - 1]) != "-main-file-name")) {
179         // Replace the input file name with the crashinfo's file name.
180         OS << ' ';
181         StringRef ShortName = llvm::sys::path::filename(CrashInfo->Filename);
182         PrintArg(OS, ShortName.str().c_str(), Quote);
183         continue;
184       }
185     }
186 
187     OS << ' ';
188     PrintArg(OS, Arg, Quote);
189   }
190 
191   if (CrashInfo && HaveCrashVFS) {
192     OS << ' ';
193     PrintArg(OS, "-ivfsoverlay", Quote);
194     OS << ' ';
195     PrintArg(OS, CrashInfo->VFSPath.str().c_str(), Quote);
196   }
197 
198   if (ResponseFile != nullptr) {
199     OS << "\n Arguments passed via response file:\n";
200     writeResponseFile(OS);
201     // Avoiding duplicated newline terminator, since FileLists are
202     // newline-separated.
203     if (Creator.getResponseFilesSupport() != Tool::RF_FileList)
204       OS << "\n";
205     OS << " (end of response file)";
206   }
207 
208   OS << Terminator;
209 }
210 
setResponseFile(const char * FileName)211 void Command::setResponseFile(const char *FileName) {
212   ResponseFile = FileName;
213   ResponseFileFlag = Creator.getResponseFileFlag();
214   ResponseFileFlag += FileName;
215 }
216 
Execute(const StringRef ** Redirects,std::string * ErrMsg,bool * ExecutionFailed) const217 int Command::Execute(const StringRef **Redirects, std::string *ErrMsg,
218                      bool *ExecutionFailed) const {
219   SmallVector<const char*, 128> Argv;
220 
221   if (ResponseFile == nullptr) {
222     Argv.push_back(Executable);
223     Argv.append(Arguments.begin(), Arguments.end());
224     Argv.push_back(nullptr);
225 
226     return llvm::sys::ExecuteAndWait(Executable, Argv.data(), /*env*/ nullptr,
227                                      Redirects, /*secondsToWait*/ 0,
228                                      /*memoryLimit*/ 0, ErrMsg,
229                                      ExecutionFailed);
230   }
231 
232   // We need to put arguments in a response file (command is too large)
233   // Open stream to store the response file contents
234   std::string RespContents;
235   llvm::raw_string_ostream SS(RespContents);
236 
237   // Write file contents and build the Argv vector
238   writeResponseFile(SS);
239   buildArgvForResponseFile(Argv);
240   Argv.push_back(nullptr);
241   SS.flush();
242 
243   // Save the response file in the appropriate encoding
244   if (std::error_code EC = writeFileWithEncoding(
245           ResponseFile, RespContents, Creator.getResponseFileEncoding())) {
246     if (ErrMsg)
247       *ErrMsg = EC.message();
248     if (ExecutionFailed)
249       *ExecutionFailed = true;
250     return -1;
251   }
252 
253   return llvm::sys::ExecuteAndWait(Executable, Argv.data(), /*env*/ nullptr,
254                                    Redirects, /*secondsToWait*/ 0,
255                                    /*memoryLimit*/ 0, ErrMsg, ExecutionFailed);
256 }
257 
FallbackCommand(const Action & Source_,const Tool & Creator_,const char * Executable_,const ArgStringList & Arguments_,std::unique_ptr<Command> Fallback_)258 FallbackCommand::FallbackCommand(const Action &Source_, const Tool &Creator_,
259                                  const char *Executable_,
260                                  const ArgStringList &Arguments_,
261                                  std::unique_ptr<Command> Fallback_)
262     : Command(Source_, Creator_, Executable_, Arguments_),
263       Fallback(std::move(Fallback_)) {}
264 
Print(raw_ostream & OS,const char * Terminator,bool Quote,CrashReportInfo * CrashInfo) const265 void FallbackCommand::Print(raw_ostream &OS, const char *Terminator,
266                             bool Quote, CrashReportInfo *CrashInfo) const {
267   Command::Print(OS, "", Quote, CrashInfo);
268   OS << " ||";
269   Fallback->Print(OS, Terminator, Quote, CrashInfo);
270 }
271 
ShouldFallback(int ExitCode)272 static bool ShouldFallback(int ExitCode) {
273   // FIXME: We really just want to fall back for internal errors, such
274   // as when some symbol cannot be mangled, when we should be able to
275   // parse something but can't, etc.
276   return ExitCode != 0;
277 }
278 
Execute(const StringRef ** Redirects,std::string * ErrMsg,bool * ExecutionFailed) const279 int FallbackCommand::Execute(const StringRef **Redirects, std::string *ErrMsg,
280                              bool *ExecutionFailed) const {
281   int PrimaryStatus = Command::Execute(Redirects, ErrMsg, ExecutionFailed);
282   if (!ShouldFallback(PrimaryStatus))
283     return PrimaryStatus;
284 
285   // Clear ExecutionFailed and ErrMsg before falling back.
286   if (ErrMsg)
287     ErrMsg->clear();
288   if (ExecutionFailed)
289     *ExecutionFailed = false;
290 
291   const Driver &D = getCreator().getToolChain().getDriver();
292   D.Diag(diag::warn_drv_invoking_fallback) << Fallback->getExecutable();
293 
294   int SecondaryStatus = Fallback->Execute(Redirects, ErrMsg, ExecutionFailed);
295   return SecondaryStatus;
296 }
297 
JobList()298 JobList::JobList() : Job(JobListClass) {}
299 
Print(raw_ostream & OS,const char * Terminator,bool Quote,CrashReportInfo * CrashInfo) const300 void JobList::Print(raw_ostream &OS, const char *Terminator, bool Quote,
301                     CrashReportInfo *CrashInfo) const {
302   for (const auto &Job : *this)
303     Job.Print(OS, Terminator, Quote, CrashInfo);
304 }
305 
clear()306 void JobList::clear() { Jobs.clear(); }
307