| /* |
| * Copyright 2006 The WebRTC Project Authors. All rights reserved. |
| * |
| * Use of this source code is governed by a BSD-style license |
| * that can be found in the LICENSE file in the root of the source |
| * tree. An additional intellectual property rights grant can be found |
| * in the file PATENTS. All contributing project authors may |
| * be found in the AUTHORS file in the root of the source tree. |
| */ |
| |
| |
| // Originally comes from shared/commandlineflags/flags.h |
| |
| // Flags are defined and declared using DEFINE_xxx and DECLARE_xxx macros, |
| // where xxx is the flag type. Flags are referred to via FLAG_yyy, |
| // where yyy is the flag name. For intialization and iteration of flags, |
| // see the FlagList class. For full programmatic access to any |
| // flag, see the Flag class. |
| // |
| // The implementation only relies and basic C++ functionality |
| // and needs no special library or STL support. |
| |
| #ifndef WEBRTC_BASE_FLAGS_H__ |
| #define WEBRTC_BASE_FLAGS_H__ |
| |
| #include "webrtc/base/checks.h" |
| #include "webrtc/base/common.h" |
| #include "webrtc/base/constructormagic.h" |
| |
| namespace rtc { |
| |
| // Internal use only. |
| union FlagValue { |
| // Note: Because in C++ non-bool values are silently converted into |
| // bool values ('bool b = "false";' results in b == true!), we pass |
| // and int argument to New_BOOL as this appears to be safer - sigh. |
| // In particular, it prevents the (not uncommon!) bug where a bool |
| // flag is defined via: DEFINE_bool(flag, "false", "some comment");. |
| static FlagValue New_BOOL(int b) { |
| FlagValue v; |
| v.b = (b != 0); |
| return v; |
| } |
| |
| static FlagValue New_INT(int i) { |
| FlagValue v; |
| v.i = i; |
| return v; |
| } |
| |
| static FlagValue New_FLOAT(float f) { |
| FlagValue v; |
| v.f = f; |
| return v; |
| } |
| |
| static FlagValue New_STRING(const char* s) { |
| FlagValue v; |
| v.s = s; |
| return v; |
| } |
| |
| bool b; |
| int i; |
| double f; |
| const char* s; |
| }; |
| |
| |
| // Each flag can be accessed programmatically via a Flag object. |
| class Flag { |
| public: |
| enum Type { BOOL, INT, FLOAT, STRING }; |
| |
| // Internal use only. |
| Flag(const char* file, const char* name, const char* comment, |
| Type type, void* variable, FlagValue default_); |
| |
| // General flag information |
| const char* file() const { return file_; } |
| const char* name() const { return name_; } |
| const char* comment() const { return comment_; } |
| |
| // Flag type |
| Type type() const { return type_; } |
| |
| // Flag variables |
| bool* bool_variable() const { |
| RTC_DCHECK_EQ(BOOL, type_); |
| return &variable_->b; |
| } |
| |
| int* int_variable() const { |
| RTC_DCHECK_EQ(INT, type_); |
| return &variable_->i; |
| } |
| |
| double* float_variable() const { |
| RTC_DCHECK_EQ(FLOAT, type_); |
| return &variable_->f; |
| } |
| |
| const char** string_variable() const { |
| RTC_DCHECK_EQ(STRING, type_); |
| return &variable_->s; |
| } |
| |
| // Default values |
| bool bool_default() const { |
| RTC_DCHECK_EQ(BOOL, type_); |
| return default_.b; |
| } |
| |
| int int_default() const { |
| RTC_DCHECK_EQ(INT, type_); |
| return default_.i; |
| } |
| |
| double float_default() const { |
| RTC_DCHECK_EQ(FLOAT, type_); |
| return default_.f; |
| } |
| |
| const char* string_default() const { |
| RTC_DCHECK_EQ(STRING, type_); |
| return default_.s; |
| } |
| |
| // Resets a flag to its default value |
| void SetToDefault(); |
| |
| // Iteration support |
| Flag* next() const { return next_; } |
| |
| // Prints flag information. The current flag value is only printed |
| // if print_current_value is set. |
| void Print(bool print_current_value); |
| |
| private: |
| const char* file_; |
| const char* name_; |
| const char* comment_; |
| |
| Type type_; |
| FlagValue* variable_; |
| FlagValue default_; |
| |
| Flag* next_; |
| |
| friend class FlagList; // accesses next_ |
| }; |
| |
| |
| // Internal use only. |
| #define DEFINE_FLAG(type, c_type, name, default, comment) \ |
| /* define and initialize the flag */ \ |
| c_type FLAG_##name = (default); \ |
| /* register the flag */ \ |
| static rtc::Flag Flag_##name(__FILE__, #name, (comment), \ |
| rtc::Flag::type, &FLAG_##name, \ |
| rtc::FlagValue::New_##type(default)) |
| |
| |
| // Internal use only. |
| #define DECLARE_FLAG(c_type, name) \ |
| /* declare the external flag */ \ |
| extern c_type FLAG_##name |
| |
| |
| // Use the following macros to define a new flag: |
| #define DEFINE_bool(name, default, comment) \ |
| DEFINE_FLAG(BOOL, bool, name, default, comment) |
| #define DEFINE_int(name, default, comment) \ |
| DEFINE_FLAG(INT, int, name, default, comment) |
| #define DEFINE_float(name, default, comment) \ |
| DEFINE_FLAG(FLOAT, double, name, default, comment) |
| #define DEFINE_string(name, default, comment) \ |
| DEFINE_FLAG(STRING, const char*, name, default, comment) |
| |
| |
| // Use the following macros to declare a flag defined elsewhere: |
| #define DECLARE_bool(name) DECLARE_FLAG(bool, name) |
| #define DECLARE_int(name) DECLARE_FLAG(int, name) |
| #define DECLARE_float(name) DECLARE_FLAG(double, name) |
| #define DECLARE_string(name) DECLARE_FLAG(const char*, name) |
| |
| |
| // The global list of all flags. |
| class FlagList { |
| public: |
| FlagList(); |
| |
| // The NULL-terminated list of all flags. Traverse with Flag::next(). |
| static Flag* list() { return list_; } |
| |
| // If file != NULL, prints information for all flags defined in file; |
| // otherwise prints information for all flags in all files. The current |
| // flag value is only printed if print_current_value is set. |
| static void Print(const char* file, bool print_current_value); |
| |
| // Lookup a flag by name. Returns the matching flag or NULL. |
| static Flag* Lookup(const char* name); |
| |
| // Helper function to parse flags: Takes an argument arg and splits it into |
| // a flag name and flag value (or NULL if they are missing). is_bool is set |
| // if the arg started with "-no" or "--no". The buffer may be used to NUL- |
| // terminate the name, it must be large enough to hold any possible name. |
| static void SplitArgument(const char* arg, |
| char* buffer, int buffer_size, |
| const char** name, const char** value, |
| bool* is_bool); |
| |
| // Set the flag values by parsing the command line. If remove_flags |
| // is set, the flags and associated values are removed from (argc, |
| // argv). Returns 0 if no error occurred. Otherwise, returns the |
| // argv index > 0 for the argument where an error occurred. In that |
| // case, (argc, argv) will remain unchanged indepdendent of the |
| // remove_flags value, and no assumptions about flag settings should |
| // be made. |
| // |
| // The following syntax for flags is accepted (both '-' and '--' are ok): |
| // |
| // --flag (bool flags only) |
| // --noflag (bool flags only) |
| // --flag=value (non-bool flags only, no spaces around '=') |
| // --flag value (non-bool flags only) |
| static int SetFlagsFromCommandLine(int* argc, |
| const char** argv, |
| bool remove_flags); |
| static inline int SetFlagsFromCommandLine(int* argc, |
| char** argv, |
| bool remove_flags) { |
| return SetFlagsFromCommandLine(argc, const_cast<const char**>(argv), |
| remove_flags); |
| } |
| |
| // Registers a new flag. Called during program initialization. Not |
| // thread-safe. |
| static void Register(Flag* flag); |
| |
| private: |
| static Flag* list_; |
| }; |
| |
| #if defined(WEBRTC_WIN) |
| // A helper class to translate Windows command line arguments into UTF8, |
| // which then allows us to just pass them to the flags system. |
| // This encapsulates all the work of getting the command line and translating |
| // it to an array of 8-bit strings; all you have to do is create one of these, |
| // and then call argc() and argv(). |
| class WindowsCommandLineArguments { |
| public: |
| WindowsCommandLineArguments(); |
| ~WindowsCommandLineArguments(); |
| |
| int argc() { return argc_; } |
| char **argv() { return argv_; } |
| private: |
| int argc_; |
| char **argv_; |
| |
| private: |
| RTC_DISALLOW_COPY_AND_ASSIGN(WindowsCommandLineArguments); |
| }; |
| #endif // WEBRTC_WIN |
| |
| } // namespace rtc |
| |
| #endif // SHARED_COMMANDLINEFLAGS_FLAGS_H__ |