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>
21using namespace clang::driver;
22using llvm::raw_ostream;
23using llvm::StringRef;
24
25Job::~Job() {}
26
27Command::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
33static 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    .Cases("-dwarf-debug-flags", "-ivfsoverlay", 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      FlagRef.startswith("-fmodules-cache-path="))
67    return 1;
68
69  return 0;
70}
71
72static bool quoteNextArg(const char *flag) {
73  return llvm::StringSwitch<bool>(flag)
74    .Case("-D", true)
75    .Default(false);
76}
77
78static 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
96void Command::Print(raw_ostream &OS, const char *Terminator, bool Quote,
97                    bool CrashReport) const {
98  OS << " \"" << Executable << '"';
99
100  for (size_t i = 0, e = Arguments.size(); i < e; ++i) {
101    const char *const Arg = Arguments[i];
102
103    if (CrashReport) {
104      if (int Skip = skipArgs(Arg)) {
105        i += Skip - 1;
106        continue;
107      }
108    }
109
110    OS << ' ';
111    PrintArg(OS, Arg, Quote);
112
113    if (CrashReport && quoteNextArg(Arg) && i + 1 < e) {
114      OS << ' ';
115      PrintArg(OS, Arguments[++i], true);
116    }
117  }
118  OS << Terminator;
119}
120
121int Command::Execute(const StringRef **Redirects, std::string *ErrMsg,
122                     bool *ExecutionFailed) const {
123  SmallVector<const char*, 128> Argv;
124  Argv.push_back(Executable);
125  for (size_t i = 0, e = Arguments.size(); i != e; ++i)
126    Argv.push_back(Arguments[i]);
127  Argv.push_back(nullptr);
128
129  return llvm::sys::ExecuteAndWait(Executable, Argv.data(), /*env*/ nullptr,
130                                   Redirects, /*secondsToWait*/ 0,
131                                   /*memoryLimit*/ 0, ErrMsg, ExecutionFailed);
132}
133
134FallbackCommand::FallbackCommand(const Action &Source_, const Tool &Creator_,
135                                 const char *Executable_,
136                                 const ArgStringList &Arguments_,
137                                 Command *Fallback_)
138    : Command(Source_, Creator_, Executable_, Arguments_), Fallback(Fallback_) {
139}
140
141void FallbackCommand::Print(raw_ostream &OS, const char *Terminator,
142                            bool Quote, bool CrashReport) const {
143  Command::Print(OS, "", Quote, CrashReport);
144  OS << " ||";
145  Fallback->Print(OS, Terminator, Quote, CrashReport);
146}
147
148static bool ShouldFallback(int ExitCode) {
149  // FIXME: We really just want to fall back for internal errors, such
150  // as when some symbol cannot be mangled, when we should be able to
151  // parse something but can't, etc.
152  return ExitCode != 0;
153}
154
155int FallbackCommand::Execute(const StringRef **Redirects, std::string *ErrMsg,
156                             bool *ExecutionFailed) const {
157  int PrimaryStatus = Command::Execute(Redirects, ErrMsg, ExecutionFailed);
158  if (!ShouldFallback(PrimaryStatus))
159    return PrimaryStatus;
160
161  // Clear ExecutionFailed and ErrMsg before falling back.
162  if (ErrMsg)
163    ErrMsg->clear();
164  if (ExecutionFailed)
165    *ExecutionFailed = false;
166
167  const Driver &D = getCreator().getToolChain().getDriver();
168  D.Diag(diag::warn_drv_invoking_fallback) << Fallback->getExecutable();
169
170  int SecondaryStatus = Fallback->Execute(Redirects, ErrMsg, ExecutionFailed);
171  return SecondaryStatus;
172}
173
174JobList::JobList() : Job(JobListClass) {}
175
176JobList::~JobList() {
177  for (iterator it = begin(), ie = end(); it != ie; ++it)
178    delete *it;
179}
180
181void JobList::Print(raw_ostream &OS, const char *Terminator, bool Quote,
182                    bool CrashReport) const {
183  for (const_iterator it = begin(), ie = end(); it != ie; ++it)
184    (*it)->Print(OS, Terminator, Quote, CrashReport);
185}
186
187void JobList::clear() {
188  DeleteContainerPointers(Jobs);
189}
190