tor-browser

command_line.h (6925B)

---

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// This class works with command lines: building and parsing.
// Switches can optionally have a value attached using an equals sign,
// as in "-switch=value".  Arguments that aren't prefixed with a
// switch prefix are considered "loose parameters".  Switch names are
// case-insensitive.  An argument of "--" will terminate switch
// parsing, causing everything after to be considered as loose
// parameters.

// There is a singleton read-only CommandLine that represents the command
// line that the current process was started with.  It must be initialized
// in main() (or whatever the platform's equivalent function is).

#ifndef BASE_COMMAND_LINE_H_
#define BASE_COMMAND_LINE_H_

#include <map>
#include <string>
#include <vector>

#include "base/basictypes.h"
#include "base/logging.h"

class InProcessBrowserTest;

class CommandLine {
public:
#if defined(XP_WIN)
 // Creates a parsed version of the given command-line string.
 // The program name is assumed to be the first item in the string.
 void ParseFromString(const std::wstring& command_line);
#else
 // Initialize from an argv vector (or directly from main()'s argv).
 CommandLine(int argc, const char* const* argv);
 explicit CommandLine(const std::vector<std::string>& argv);
#endif

 // Construct a new, empty command line.
 // |program| is the name of the program to run (aka argv[0]).
 // TODO(port): should be a FilePath.
 explicit CommandLine(const std::wstring& program);

 // Initialize the current process CommandLine singleton.  On Windows,
 // ignores its arguments (we instead parse GetCommandLineW()
 // directly) because we don't trust the CRT's parsing of the command
 // line, but it still must be called to set up the command line.
 static void Init(int argc, const char* const* argv);

 // Destroys the current process CommandLine singleton. This is necessary if
 // you want to reset the base library to its initial state (for example in an
 // outer library that needs to be able to terminate, and be re-initialized).
 // If Init is called only once, e.g. in main(), calling Terminate() is not
 // necessary.
 static void Terminate();

 // Get the singleton CommandLine representing the current process's
 // command line.
 static const CommandLine* ForCurrentProcess() {
   DCHECK(current_process_commandline_);
   return current_process_commandline_;
 }

 static bool IsInitialized() { return !!current_process_commandline_; }

 // Returns true if this command line contains the given switch.
 // (Switch names are case-insensitive.)
 bool HasSwitch(const std::wstring& switch_string) const;

 // Returns the value associated with the given switch.  If the
 // switch has no value or isn't present, this method returns
 // the empty string.
 std::wstring GetSwitchValue(const std::wstring& switch_string) const;

 // Get the remaining arguments to the command.
 // WARNING: this is incorrect on POSIX; we must do string conversions.
 std::vector<std::wstring> GetLooseValues() const;

#if defined(XP_WIN)
 // Returns the original command line string.
 const std::wstring& command_line_string() const {
   return command_line_string_;
 }
#else
 // Returns the original command line string as a vector of strings.
 const std::vector<std::string>& argv() const { return argv_; }
#endif

 // Returns the program part of the command line string (the first item).
 std::wstring program() const;

 // Return a copy of the string prefixed with a switch prefix.
 // Used internally.
 static std::wstring PrefixedSwitchString(const std::wstring& switch_string);

 // Return a copy of the string prefixed with a switch prefix,
 // and appended with the given value. Used internally.
 static std::wstring PrefixedSwitchStringWithValue(
     const std::wstring& switch_string, const std::wstring& value_string);

 // Appends the given switch string (preceded by a space and a switch
 // prefix) to the given string.
 void AppendSwitch(const std::wstring& switch_string);

 // Appends the given switch string (preceded by a space and a switch
 // prefix) to the given string, with the given value attached.
 void AppendSwitchWithValue(const std::wstring& switch_string,
                            const std::wstring& value_string);

 // Append a loose value to the command line.
 void AppendLooseValue(const std::wstring& value);

#if defined(XP_WIN)
 void AppendLooseValue(const wchar_t* value) {
   AppendLooseValue(std::wstring(value));
 }
#endif

 // Append the arguments from another command line to this one.
 // If |include_program| is true, include |other|'s program as well.
 void AppendArguments(const CommandLine& other, bool include_program);

 // On POSIX systems it's common to run processes via a wrapper (like
 // "valgrind" or "gdb --args").
 void PrependWrapper(const std::wstring& wrapper);

private:
 friend class InProcessBrowserTest;

 CommandLine() {}

 // Used by InProcessBrowserTest.
 static CommandLine* ForCurrentProcessMutable() {
   DCHECK(current_process_commandline_);
   return current_process_commandline_;
 }

 // The singleton CommandLine instance representing the current process's
 // command line.
 static CommandLine* current_process_commandline_;

 // We store a platform-native version of the command line, used when building
 // up a new command line to be executed.  This ifdef delimits that code.

#if defined(XP_WIN)
 // The quoted, space-separated command-line string.
 std::wstring command_line_string_;

 // The name of the program.
 std::wstring program_;

 // The type of native command line arguments.
 typedef std::wstring StringType;

#else
 // The argv array, with the program name in argv_[0].
 std::vector<std::string> argv_;

 // The type of native command line arguments.
 typedef std::string StringType;

 // Shared by the two POSIX constructor forms.  Initalize from argv_.
 void InitFromArgv();
#endif

 // Returns true and fills in |switch_string| and |switch_value|
 // if |parameter_string| represents a switch.
 static bool IsSwitch(const StringType& parameter_string,
                      std::string* switch_string, StringType* switch_value);

 // Parsed-out values.
 std::map<std::string, StringType> switches_;

 // Non-switch command-line arguments.
 std::vector<StringType> loose_values_;

 // We allow copy constructors, because a common pattern is to grab a
 // copy of the current process's command line and then add some
 // flags to it.  E.g.:
 //   CommandLine cl(*CommandLine::ForCurrentProcess());
 //   cl.AppendSwitch(...);
};

#endif  // BASE_COMMAND_LINE_H_