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.
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.
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().
15 #ifndef BASE_COMMAND_LINE_H_
16 #define BASE_COMMAND_LINE_H_
23 #include "base/base_export.h"
24 #include "base/strings/string16.h"
25 #include "base/strings/string_piece.h"
26 #include "build/build_config.h"
32 class BASE_EXPORT CommandLine {
35 // The native command line string type.
36 using StringType = string16;
37 #elif defined(OS_POSIX) || defined(OS_FUCHSIA)
38 using StringType = std::string;
41 using CharType = StringType::value_type;
42 using StringVector = std::vector<StringType>;
43 using SwitchMap = std::map<std::string, StringType, std::less<>>;
45 // A constructor for CommandLines that only carry switches and arguments.
46 enum NoProgram { NO_PROGRAM };
47 explicit CommandLine(NoProgram no_program);
49 // Construct a new command line with |program| as argv[0].
50 explicit CommandLine(const FilePath& program);
52 // Construct a new command line from an argument list.
53 CommandLine(int argc, const CharType* const* argv);
54 explicit CommandLine(const StringVector& argv);
56 // Override copy and assign to ensure |switches_by_stringpiece_| is valid.
57 CommandLine(const CommandLine& other);
58 CommandLine& operator=(const CommandLine& other);
63 // By default this class will treat command-line arguments beginning with
64 // slashes as switches on Windows, but not other platforms.
66 // If this behavior is inappropriate for your application, you can call this
67 // function BEFORE initializing the current process' global command line
68 // object and the behavior will be the same as Posix systems (only hyphens
69 // begin switches, everything else will be an arg).
70 static void set_slash_is_not_a_switch();
72 // Normally when the CommandLine singleton is initialized it gets the command
73 // line via the GetCommandLineW API and then uses the shell32 API
74 // CommandLineToArgvW to parse the command line and convert it back to
75 // argc and argv. Tests who don't want this dependency on shell32 and need
76 // to honor the arguments passed in should use this function.
77 static void InitUsingArgvForTesting(int argc, const char* const* argv);
80 // Initialize the current process CommandLine singleton. On Windows, ignores
81 // its arguments (we instead parse GetCommandLineW() directly) because we
82 // don't trust the CRT's parsing of the command line, but it still must be
83 // called to set up the command line. Returns false if initialization has
84 // already occurred, and true otherwise. Only the caller receiving a 'true'
85 // return value should take responsibility for calling Reset.
86 static bool Init(int argc, const char* const* argv);
88 // Destroys the current process CommandLine singleton. This is necessary if
89 // you want to reset the base library to its initial state (for example, in an
90 // outer library that needs to be able to terminate, and be re-initialized).
91 // If Init is called only once, as in main(), Reset() is not necessary.
92 // Do not call this in tests. Use base::test::ScopedCommandLine instead.
95 // Get the singleton CommandLine representing the current process's
96 // command line. Note: returned value is mutable, but not thread safe;
97 // only mutate if you know what you're doing!
98 static CommandLine* ForCurrentProcess();
100 // Returns true if the CommandLine has been initialized for the given process.
101 static bool InitializedForCurrentProcess();
104 static CommandLine FromString(const string16& command_line);
107 // Initialize from an argv vector.
108 void InitFromArgv(int argc, const CharType* const* argv);
109 void InitFromArgv(const StringVector& argv);
111 // Constructs and returns the represented command line string.
112 // CAUTION! This should be avoided on POSIX because quoting behavior is
114 StringType GetCommandLineString() const {
115 return GetCommandLineStringInternal(false);
119 // Constructs and returns the represented command line string. Assumes the
120 // command line contains placeholders (eg, %1) and quotes any program or
121 // argument with a '%' in it. This should be avoided unless the placeholder is
122 // required by an external interface (eg, the Windows registry), because it is
123 // not generally safe to replace it with an arbitrary string. If possible,
124 // placeholders should be replaced *before* converting the command line to a
126 StringType GetCommandLineStringWithPlaceholders() const {
127 return GetCommandLineStringInternal(true);
131 // Constructs and returns the represented arguments string.
132 // CAUTION! This should be avoided on POSIX because quoting behavior is
134 StringType GetArgumentsString() const {
135 return GetArgumentsStringInternal(false);
139 // Constructs and returns the represented arguments string. Assumes the
140 // command line contains placeholders (eg, %1) and quotes any argument with a
141 // '%' in it. This should be avoided unless the placeholder is required by an
142 // external interface (eg, the Windows registry), because it is not generally
143 // safe to replace it with an arbitrary string. If possible, placeholders
144 // should be replaced *before* converting the arguments to a string.
145 StringType GetArgumentsStringWithPlaceholders() const {
146 return GetArgumentsStringInternal(true);
150 // Returns the original command line string as a vector of strings.
151 const StringVector& argv() const { return argv_; }
153 // Get and Set the program part of the command line string (the first item).
154 FilePath GetProgram() const;
155 void SetProgram(const FilePath& program);
157 // Returns true if this command line contains the given switch.
158 // Switch names must be lowercase.
159 // The second override provides an optimized version to avoid inlining codegen
160 // at every callsite to find the length of the constant and construct a
162 bool HasSwitch(const StringPiece& switch_string) const;
163 bool HasSwitch(const char switch_constant[]) const;
165 // Returns the value associated with the given switch. If the switch has no
166 // value or isn't present, this method returns the empty string.
167 // Switch names must be lowercase.
168 std::string GetSwitchValueASCII(const StringPiece& switch_string) const;
169 FilePath GetSwitchValuePath(const StringPiece& switch_string) const;
170 StringType GetSwitchValueNative(const StringPiece& switch_string) const;
172 // Get a copy of all switches, along with their values.
173 const SwitchMap& GetSwitches() const { return switches_; }
175 // Append a switch [with optional value] to the command line.
176 // Note: Switches will precede arguments regardless of appending order.
177 void AppendSwitch(const std::string& switch_string);
178 void AppendSwitchPath(const std::string& switch_string,
179 const FilePath& path);
180 void AppendSwitchNative(const std::string& switch_string,
181 const StringType& value);
182 void AppendSwitchASCII(const std::string& switch_string,
183 const std::string& value);
185 // Copy a set of switches (and any values) from another command line.
186 // Commonly used when launching a subprocess.
187 void CopySwitchesFrom(const CommandLine& source,
188 const char* const switches[],
191 // Get the remaining arguments to the command.
192 StringVector GetArgs() const;
194 // Append an argument to the command line. Note that the argument is quoted
195 // properly such that it is interpreted as one argument to the target command.
196 // AppendArg is primarily for ASCII; non-ASCII input is interpreted as UTF-8.
197 // Note: Switches will precede arguments regardless of appending order.
198 void AppendArg(const std::string& value);
199 void AppendArgPath(const FilePath& value);
200 void AppendArgNative(const StringType& value);
202 // Append the switches and arguments from another command line to this one.
203 // If |include_program| is true, include |other|'s program as well.
204 void AppendArguments(const CommandLine& other, bool include_program);
206 // Insert a command before the current command.
207 // Common for debuggers, like "gdb --args".
208 void PrependWrapper(const StringType& wrapper);
211 // Initialize by parsing the given command line string.
212 // The program name is assumed to be the first item in the string.
213 void ParseFromString(const string16& command_line);
217 // Disallow default constructor; a program name must be explicitly specified.
218 CommandLine() = delete;
219 // Allow the copy constructor. A common pattern is to copy of the current
220 // process's command line and then add some flags to it. For example:
221 // CommandLine cl(*CommandLine::ForCurrentProcess());
222 // cl.AppendSwitch(...);
224 // Internal version of GetCommandLineString. If |quote_placeholders| is true,
225 // also quotes parts with '%' in them.
226 StringType GetCommandLineStringInternal(bool quote_placeholders) const;
228 // Internal version of GetArgumentsString. If |quote_placeholders| is true,
229 // also quotes parts with '%' in them.
230 StringType GetArgumentsStringInternal(bool quote_placeholders) const;
232 // The singleton CommandLine representing the current process's command line.
233 static CommandLine* current_process_commandline_;
235 // The argv array: { program, [(--|-|/)switch[=value]]*, [--], [argument]* }
238 // Parsed-out switch keys and values.
241 // The index after the program and switches, any arguments start here.
247 #endif // BASE_COMMAND_LINE_H_