1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 // This class works with command lines: building and parsing. 6 // Arguments with prefixes ('--', '-', and on Windows, '/') are switches. 7 // Switches will precede all other arguments without switch prefixes. 8 // Switches can optionally have values, delimited by '=', e.g., "-switch=value". 9 // An argument of "--" will terminate switch parsing during initialization, 10 // interpreting subsequent tokens as non-switch arguments, regardless of prefix. 11 12 // There is a singleton read-only CommandLine that represents the command line 13 // that the current process was started with. It must be initialized in main(). 14 15 #ifndef BASE_COMMAND_LINE_H_ 16 #define BASE_COMMAND_LINE_H_ 17 18 #include <stddef.h> 19 #include <map> 20 #include <string> 21 #include <vector> 22 23 #include "base/base_export.h" 24 #include "build/build_config.h" 25 26 namespace base { 27 28 class FilePath; 29 30 class BASE_EXPORT CommandLine { 31 public: 32 #if defined(OS_WIN) 33 // The native command line string type. 34 typedef std::wstring StringType; 35 #elif defined(OS_POSIX) 36 typedef std::string StringType; 37 #endif 38 39 typedef StringType::value_type CharType; 40 typedef std::vector<StringType> StringVector; 41 typedef std::map<std::string, StringType> SwitchMap; 42 43 // A constructor for CommandLines that only carry switches and arguments. 44 enum NoProgram { NO_PROGRAM }; 45 explicit CommandLine(NoProgram no_program); 46 47 // Construct a new command line with |program| as argv[0]. 48 explicit CommandLine(const FilePath& program); 49 50 // Construct a new command line from an argument list. 51 CommandLine(int argc, const CharType* const* argv); 52 explicit CommandLine(const StringVector& argv); 53 54 ~CommandLine(); 55 56 #if defined(OS_WIN) 57 // By default this class will treat command-line arguments beginning with 58 // slashes as switches on Windows, but not other platforms. 59 // 60 // If this behavior is inappropriate for your application, you can call this 61 // function BEFORE initializing the current process' global command line 62 // object and the behavior will be the same as Posix systems (only hyphens 63 // begin switches, everything else will be an arg). 64 static void set_slash_is_not_a_switch(); 65 #endif 66 67 // Initialize the current process CommandLine singleton. On Windows, ignores 68 // its arguments (we instead parse GetCommandLineW() directly) because we 69 // don't trust the CRT's parsing of the command line, but it still must be 70 // called to set up the command line. Returns false if initialization has 71 // already occurred, and true otherwise. Only the caller receiving a 'true' 72 // return value should take responsibility for calling Reset. 73 static bool Init(int argc, const char* const* argv); 74 75 // Destroys the current process CommandLine singleton. This is necessary if 76 // you want to reset the base library to its initial state (for example, in an 77 // outer library that needs to be able to terminate, and be re-initialized). 78 // If Init is called only once, as in main(), Reset() is not necessary. 79 static void Reset(); 80 81 // Get the singleton CommandLine representing the current process's 82 // command line. Note: returned value is mutable, but not thread safe; 83 // only mutate if you know what you're doing! 84 static CommandLine* ForCurrentProcess(); 85 86 // Returns true if the CommandLine has been initialized for the given process. 87 static bool InitializedForCurrentProcess(); 88 89 #if defined(OS_WIN) 90 static CommandLine FromString(const std::wstring& command_line); 91 #endif 92 93 // Initialize from an argv vector. 94 void InitFromArgv(int argc, const CharType* const* argv); 95 void InitFromArgv(const StringVector& argv); 96 97 // Constructs and returns the represented command line string. 98 // CAUTION! This should be avoided on POSIX because quoting behavior is 99 // unclear. 100 StringType GetCommandLineString() const; 101 102 // Constructs and returns the represented arguments string. 103 // CAUTION! This should be avoided on POSIX because quoting behavior is 104 // unclear. 105 StringType GetArgumentsString() const; 106 107 // Returns the original command line string as a vector of strings. argv()108 const StringVector& argv() const { return argv_; } 109 110 // Get and Set the program part of the command line string (the first item). 111 FilePath GetProgram() const; 112 void SetProgram(const FilePath& program); 113 114 // Returns true if this command line contains the given switch. 115 // (Switch names are case-insensitive). 116 bool HasSwitch(const std::string& switch_string) const; 117 118 // Returns the value associated with the given switch. If the switch has no 119 // value or isn't present, this method returns the empty string. 120 std::string GetSwitchValueASCII(const std::string& switch_string) const; 121 FilePath GetSwitchValuePath(const std::string& switch_string) const; 122 StringType GetSwitchValueNative(const std::string& switch_string) const; 123 124 // Get a copy of all switches, along with their values. GetSwitches()125 const SwitchMap& GetSwitches() const { return switches_; } 126 127 // Append a switch [with optional value] to the command line. 128 // Note: Switches will precede arguments regardless of appending order. 129 void AppendSwitch(const std::string& switch_string); 130 void AppendSwitchPath(const std::string& switch_string, 131 const FilePath& path); 132 void AppendSwitchNative(const std::string& switch_string, 133 const StringType& value); 134 void AppendSwitchASCII(const std::string& switch_string, 135 const std::string& value); 136 137 // Copy a set of switches (and any values) from another command line. 138 // Commonly used when launching a subprocess. 139 void CopySwitchesFrom(const CommandLine& source, 140 const char* const switches[], 141 size_t count); 142 143 // Get the remaining arguments to the command. 144 StringVector GetArgs() const; 145 146 // Append an argument to the command line. Note that the argument is quoted 147 // properly such that it is interpreted as one argument to the target command. 148 // AppendArg is primarily for ASCII; non-ASCII input is interpreted as UTF-8. 149 // Note: Switches will precede arguments regardless of appending order. 150 void AppendArg(const std::string& value); 151 void AppendArgPath(const FilePath& value); 152 void AppendArgNative(const StringType& value); 153 154 // Append the switches and arguments from another command line to this one. 155 // If |include_program| is true, include |other|'s program as well. 156 void AppendArguments(const CommandLine& other, bool include_program); 157 158 // Insert a command before the current command. 159 // Common for debuggers, like "valgrind" or "gdb --args". 160 void PrependWrapper(const StringType& wrapper); 161 162 #if defined(OS_WIN) 163 // Initialize by parsing the given command line string. 164 // The program name is assumed to be the first item in the string. 165 void ParseFromString(const std::wstring& command_line); 166 #endif 167 168 private: 169 // Disallow default constructor; a program name must be explicitly specified. 170 CommandLine(); 171 // Allow the copy constructor. A common pattern is to copy of the current 172 // process's command line and then add some flags to it. For example: 173 // CommandLine cl(*CommandLine::ForCurrentProcess()); 174 // cl.AppendSwitch(...); 175 176 // The singleton CommandLine representing the current process's command line. 177 static CommandLine* current_process_commandline_; 178 179 // The argv array: { program, [(--|-|/)switch[=value]]*, [--], [argument]* } 180 StringVector argv_; 181 182 // Parsed-out switch keys and values. 183 SwitchMap switches_; 184 185 // The index after the program and switches, any arguments start here. 186 size_t begin_args_; 187 }; 188 189 } // namespace base 190 191 // TODO(brettw) remove once all callers specify the namespace properly. 192 using base::CommandLine; 193 194 #endif // BASE_COMMAND_LINE_H_ 195