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/STLExtras.h"
16 #include "llvm/ADT/StringRef.h"
17 #include "llvm/ADT/StringSwitch.h"
18 #include "llvm/Support/Program.h"
19 #include "llvm/Support/raw_ostream.h"
20 #include <cassert>
21 using namespace clang::driver;
22 using llvm::raw_ostream;
23 using llvm::StringRef;
24 
25 Job::~Job() {}
26 
27 Command::Command(const Action &_Source, const Tool &_Creator,
28                  const char *_Executable,
29                  const ArgStringList &_Arguments)
30     : Job(CommandClass), Source(_Source), Creator(_Creator),
31       Executable(_Executable), Arguments(_Arguments) {}
32 
33 static int skipArgs(const char *Flag) {
34   // These flags are all of the form -Flag <Arg> and are treated as two
35   // arguments.  Therefore, we need to skip the flag and the next argument.
36   bool Res = llvm::StringSwitch<bool>(Flag)
37     .Cases("-I", "-MF", "-MT", "-MQ", true)
38     .Cases("-o", "-coverage-file", "-dependency-file", true)
39     .Cases("-fdebug-compilation-dir", "-idirafter", true)
40     .Cases("-include", "-include-pch", "-internal-isystem", true)
41     .Cases("-internal-externc-isystem", "-iprefix", "-iwithprefix", true)
42     .Cases("-iwithprefixbefore", "-isysroot", "-isystem", "-iquote", true)
43     .Cases("-resource-dir", "-serialize-diagnostic-file", true)
44     .Case("-dwarf-debug-flags", true)
45     .Default(false);
46 
47   // Match found.
48   if (Res)
49     return 2;
50 
51   // The remaining flags are treated as a single argument.
52 
53   // These flags are all of the form -Flag and have no second argument.
54   Res = llvm::StringSwitch<bool>(Flag)
55     .Cases("-M", "-MM", "-MG", "-MP", "-MD", true)
56     .Case("-MMD", true)
57     .Default(false);
58 
59   // Match found.
60   if (Res)
61     return 1;
62 
63   // These flags are treated as a single argument (e.g., -F<Dir>).
64   StringRef FlagRef(Flag);
65   if (FlagRef.startswith("-F") || FlagRef.startswith("-I"))
66     return 1;
67 
68   return 0;
69 }
70 
71 static bool quoteNextArg(const char *flag) {
72   return llvm::StringSwitch<bool>(flag)
73     .Case("-D", true)
74     .Default(false);
75 }
76 
77 static void PrintArg(raw_ostream &OS, const char *Arg, bool Quote) {
78   const bool Escape = std::strpbrk(Arg, "\"\\$");
79 
80   if (!Quote && !Escape) {
81     OS << Arg;
82     return;
83   }
84 
85   // Quote and escape. This isn't really complete, but good enough.
86   OS << '"';
87   while (const char c = *Arg++) {
88     if (c == '"' || c == '\\' || c == '$')
89       OS << '\\';
90     OS << c;
91   }
92   OS << '"';
93 }
94 
95 void Command::Print(raw_ostream &OS, const char *Terminator, bool Quote,
96                     bool CrashReport) const {
97   OS << " \"" << Executable << '"';
98 
99   for (size_t i = 0, e = Arguments.size(); i < e; ++i) {
100     const char *const Arg = Arguments[i];
101 
102     if (CrashReport) {
103       if (int Skip = skipArgs(Arg)) {
104         i += Skip - 1;
105         continue;
106       }
107     }
108 
109     OS << ' ';
110     PrintArg(OS, Arg, Quote);
111 
112     if (CrashReport && quoteNextArg(Arg) && i + 1 < e) {
113       OS << ' ';
114       PrintArg(OS, Arguments[++i], true);
115     }
116   }
117   OS << Terminator;
118 }
119 
120 int Command::Execute(const StringRef **Redirects, std::string *ErrMsg,
121                      bool *ExecutionFailed) const {
122   SmallVector<const char*, 128> Argv;
123   Argv.push_back(Executable);
124   for (size_t i = 0, e = Arguments.size(); i != e; ++i)
125     Argv.push_back(Arguments[i]);
126   Argv.push_back(0);
127 
128   return llvm::sys::ExecuteAndWait(Executable, Argv.data(), /*env*/ 0,
129                                    Redirects, /*secondsToWait*/ 0,
130                                    /*memoryLimit*/ 0, ErrMsg, ExecutionFailed);
131 }
132 
133 FallbackCommand::FallbackCommand(const Action &Source_, const Tool &Creator_,
134                                  const char *Executable_,
135                                  const ArgStringList &Arguments_,
136                                  Command *Fallback_)
137     : Command(Source_, Creator_, Executable_, Arguments_), Fallback(Fallback_) {
138 }
139 
140 void FallbackCommand::Print(raw_ostream &OS, const char *Terminator,
141                             bool Quote, bool CrashReport) const {
142   Command::Print(OS, "", Quote, CrashReport);
143   OS << " ||";
144   Fallback->Print(OS, Terminator, Quote, CrashReport);
145 }
146 
147 static bool ShouldFallback(int ExitCode) {
148   // FIXME: We really just want to fall back for internal errors, such
149   // as when some symbol cannot be mangled, when we should be able to
150   // parse something but can't, etc.
151   return ExitCode != 0;
152 }
153 
154 int FallbackCommand::Execute(const StringRef **Redirects, std::string *ErrMsg,
155                              bool *ExecutionFailed) const {
156   int PrimaryStatus = Command::Execute(Redirects, ErrMsg, ExecutionFailed);
157   if (!ShouldFallback(PrimaryStatus))
158     return PrimaryStatus;
159 
160   // Clear ExecutionFailed and ErrMsg before falling back.
161   if (ErrMsg)
162     ErrMsg->clear();
163   if (ExecutionFailed)
164     *ExecutionFailed = false;
165 
166   const Driver &D = getCreator().getToolChain().getDriver();
167   D.Diag(diag::warn_drv_invoking_fallback) << Fallback->getExecutable();
168 
169   int SecondaryStatus = Fallback->Execute(Redirects, ErrMsg, ExecutionFailed);
170   return SecondaryStatus;
171 }
172 
173 JobList::JobList() : Job(JobListClass) {}
174 
175 JobList::~JobList() {
176   for (iterator it = begin(), ie = end(); it != ie; ++it)
177     delete *it;
178 }
179 
180 void JobList::Print(raw_ostream &OS, const char *Terminator, bool Quote,
181                     bool CrashReport) const {
182   for (const_iterator it = begin(), ie = end(); it != ie; ++it)
183     (*it)->Print(OS, Terminator, Quote, CrashReport);
184 }
185 
186 void JobList::clear() {
187   DeleteContainerPointers(Jobs);
188 }
189