compiler-rt/lib/fuzzer/FuzzerCommand.h

   1 //===- FuzzerCommand.h - Interface representing a process -------*- C++ -* ===//
   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 // FuzzerCommand represents a command to run in a subprocess.  It allows callers
   9 // to manage command line arguments and output and error streams.
  10 //===----------------------------------------------------------------------===//
  11
  12 #ifndef LLVM_FUZZER_COMMAND_H
  13 #define LLVM_FUZZER_COMMAND_H
  14
  15 #include "FuzzerDefs.h"
  16 #include "FuzzerIO.h"
  17
  18 #include <algorithm>
  19 #include <sstream>
  20 #include <string>
  21 #include <vector>
  22
  23 namespace fuzzer {
  24
  25 class Command final {
  26 public:
  27   // This command line flag is used to indicate that the remaining command line
  28   // is immutable, meaning this flag effectively marks the end of the mutable
  29   // argument list.
  30   static inline const char *ignoreRemainingArgs() {
  31     return "-ignore_remaining_args=1";
  32   }
  33
  34   Command() : CombinedOutAndErr(false) {}
  35
  36   explicit Command(const Vector<std::string> &ArgsToAdd)
  37       : Args(ArgsToAdd), CombinedOutAndErr(false) {}
  38
  39   explicit Command(const Command &Other)
  40       : Args(Other.Args), CombinedOutAndErr(Other.CombinedOutAndErr),
  41         OutputFile(Other.OutputFile) {}
  42
  43   Command &operator=(const Command &Other) {
  44     Args = Other.Args;
  45     CombinedOutAndErr = Other.CombinedOutAndErr;
  46     OutputFile = Other.OutputFile;
  47     return *this;
  48   }
  49
  50   ~Command() {}
  51
  52   // Returns true if the given Arg is present in Args.  Only checks up to
  53   // "-ignore_remaining_args=1".
  54   bool hasArgument(const std::string &Arg) const {
  55     auto i = endMutableArgs();
  56     return std::find(Args.begin(), i, Arg) != i;
  57   }
  58
  59   // Gets all of the current command line arguments, **including** those after
  60   // "-ignore-remaining-args=1".
  61   const Vector<std::string> &getArguments() const { return Args; }
  62
  63   // Adds the given argument before "-ignore_remaining_args=1", or at the end
  64   // if that flag isn't present.
  65   void addArgument(const std::string &Arg) {
  66     Args.insert(endMutableArgs(), Arg);
  67   }
  68
  69   // Adds all given arguments before "-ignore_remaining_args=1", or at the end
  70   // if that flag isn't present.
  71   void addArguments(const Vector<std::string> &ArgsToAdd) {
  72     Args.insert(endMutableArgs(), ArgsToAdd.begin(), ArgsToAdd.end());
  73   }
  74
  75   // Removes the given argument from the command argument list.  Ignores any
  76   // occurrences after "-ignore_remaining_args=1", if present.
  77   void removeArgument(const std::string &Arg) {
  78     auto i = endMutableArgs();
  79     Args.erase(std::remove(Args.begin(), i, Arg), i);
  80   }
  81
  82   // Like hasArgument, but checks for "-[Flag]=...".
  83   bool hasFlag(const std::string &Flag) const {
  84     std::string Arg("-" + Flag + "=");
  85     auto IsMatch = [&](const std::string &Other) {
  86       return Arg.compare(0, std::string::npos, Other, 0, Arg.length()) == 0;
  87     };
  88     return std::any_of(Args.begin(), endMutableArgs(), IsMatch);
  89   }
  90
  91   // Returns the value of the first instance of a given flag, or an empty string
  92   // if the flag isn't present.  Ignores any occurrences after
  93   // "-ignore_remaining_args=1", if present.
  94   std::string getFlagValue(const std::string &Flag) const {
  95     std::string Arg("-" + Flag + "=");
  96     auto IsMatch = [&](const std::string &Other) {
  97       return Arg.compare(0, std::string::npos, Other, 0, Arg.length()) == 0;
  98     };
  99     auto i = endMutableArgs();
 100     auto j = std::find_if(Args.begin(), i, IsMatch);
 101     std::string result;
 102     if (j != i) {
 103       result = j->substr(Arg.length());
 104     }
 105     return result;
 106   }
 107
 108   // Like AddArgument, but adds "-[Flag]=[Value]".
 109   void addFlag(const std::string &Flag, const std::string &Value) {
 110     addArgument("-" + Flag + "=" + Value);
 111   }
 112
 113   // Like RemoveArgument, but removes "-[Flag]=...".
 114   void removeFlag(const std::string &Flag) {
 115     std::string Arg("-" + Flag + "=");
 116     auto IsMatch = [&](const std::string &Other) {
 117       return Arg.compare(0, std::string::npos, Other, 0, Arg.length()) == 0;
 118     };
 119     auto i = endMutableArgs();
 120     Args.erase(std::remove_if(Args.begin(), i, IsMatch), i);
 121   }
 122
 123   // Returns whether the command's stdout is being written to an output file.
 124   bool hasOutputFile() const { return !OutputFile.empty(); }
 125
 126   // Returns the currently set output file.
 127   const std::string &getOutputFile() const { return OutputFile; }
 128
 129   // Configures the command to redirect its output to the name file.
 130   void setOutputFile(const std::string &FileName) { OutputFile = FileName; }
 131
 132   // Returns whether the command's stderr is redirected to stdout.
 133   bool isOutAndErrCombined() const { return CombinedOutAndErr; }
 134
 135   // Sets whether to redirect the command's stderr to its stdout.
 136   void combineOutAndErr(bool combine = true) { CombinedOutAndErr = combine; }
 137
 138   // Returns a string representation of the command.  On many systems this will
 139   // be the equivalent command line.
 140   std::string toString() const {
 141     std::stringstream SS;
 142     for (auto arg : getArguments())
 143       SS << arg << " ";
 144     if (hasOutputFile())
 145       SS << ">" << getOutputFile() << " ";
 146     if (isOutAndErrCombined())
 147       SS << "2>&1 ";
 148     std::string result = SS.str();
 149     if (!result.empty())
 150       result = result.substr(0, result.length() - 1);
 151     return result;
 152   }
 153
 154 private:
 155   Command(Command &&Other) = delete;
 156   Command &operator=(Command &&Other) = delete;
 157
 158   Vector<std::string>::iterator endMutableArgs() {
 159     return std::find(Args.begin(), Args.end(), ignoreRemainingArgs());
 160   }
 161
 162   Vector<std::string>::const_iterator endMutableArgs() const {
 163     return std::find(Args.begin(), Args.end(), ignoreRemainingArgs());
 164   }
 165
 166   // The command arguments.  Args[0] is the command name.
 167   Vector<std::string> Args;
 168
 169   // True indicates stderr is redirected to stdout.
 170   bool CombinedOutAndErr;
 171
 172   // If not empty, stdout is redirected to the named file.
 173   std::string OutputFile;
 174 };
 175
 176 } // namespace fuzzer
 177
 178 #endif // LLVM_FUZZER_COMMAND_H