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// Copyright (c) 2006, Google Inc.
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// All rights reserved.
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// Redistribution and use in source and binary forms, with or without
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// modification, are permitted provided that the following conditions are
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// * Redistributions of source code must retain the above copyright
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// notice, this list of conditions and the following disclaimer.
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// * Redistributions in binary form must reproduce the above
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// copyright notice, this list of conditions and the following disclaimer
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// in the documentation and/or other materials provided with the
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// * Neither the name of Google Inc. nor the names of its
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// contributors may be used to endorse or promote products derived from
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// this software without specific prior written permission.
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// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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// Revamped and reorganized by Craig Silverstein
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// This is the file that should be included by any file which declares
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// or defines a command line flag or wants to parse command line flags
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// or print a program usage message (which will include information about
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// flags). Executive summary, in the form of an example foo.cc file:
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// #include "foo.h" // foo.h has a line "DECLARE_int32(start);"
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// #include "validators.h" // hypothetical file defining ValidateIsFile()
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// DEFINE_int32(end, 1000, "The last record to read");
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// DEFINE_string(filename, "my_file.txt", "The file to read");
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// // Crash if the specified file does not exist.
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// static bool dummy = RegisterFlagValidator(&FLAGS_filename,
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// DECLARE_bool(verbose); // some other file has a DEFINE_bool(verbose, ...)
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// if (FLAGS_verbose) printf("Records %d-%d\n", FLAGS_start, FLAGS_end);
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// Then, at the command-line:
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// ./foo --noverbose --start=5 --end=100
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// For more details, see
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// --- A note about thread-safety:
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// We describe many functions in this routine as being thread-hostile,
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// thread-compatible, or thread-safe. Here are the meanings we use:
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// thread-safe: it is safe for multiple threads to call this routine
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// (or, when referring to a class, methods of this class)
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// thread-hostile: it is not safe for multiple threads to call this
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// routine (or methods of this class) concurrently. In gflags,
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// most thread-hostile routines are intended to be called early in,
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// or even before, main() -- that is, before threads are spawned.
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// thread-compatible: it is safe for multiple threads to read from
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// this variable (when applied to variables), or to call const
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// methods of this class (when applied to classes), as long as no
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// other thread is writing to the variable or calling non-const
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// methods of this class.
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#ifndef GFLAGS_GFLAGS_H_
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#define GFLAGS_GFLAGS_H_
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#include "gflags/gflags_declare.h" // IWYU pragma: export
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// We always want to export variables defined in user code
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#ifndef GFLAGS_DLL_DEFINE_FLAG
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# if GFLAGS_IS_A_DLL && defined(_MSC_VER)
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# define GFLAGS_DLL_DEFINE_FLAG __declspec(dllexport)
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# define GFLAGS_DLL_DEFINE_FLAG
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namespace GFLAGS_NAMESPACE {
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// --------------------------------------------------------------------
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// To actually define a flag in a file, use DEFINE_bool,
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// DEFINE_string, etc. at the bottom of this file. You may also find
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// it useful to register a validator with the flag. This ensures that
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// when the flag is parsed from the commandline, or is later set via
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// SetCommandLineOption, we call the validation function. It is _not_
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// called when you assign the value to the flag directly using the = operator.
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// The validation function should return true if the flag value is valid, and
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// false otherwise. If the function returns false for the new setting of the
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// flag, the flag will retain its current value. If it returns false for the
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// default value, ParseCommandLineFlags() will die.
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// This function is safe to call at global construct time (as in the
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// static bool ValidatePort(const char* flagname, int32 value) {
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// if (value > 0 && value < 32768) // value is ok
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// printf("Invalid value for --%s: %d\n", flagname, (int)value);
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// DEFINE_int32(port, 0, "What port to listen on");
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// static bool dummy = RegisterFlagValidator(&FLAGS_port, &ValidatePort);
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// Returns true if successfully registered, false if not (because the
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// first argument doesn't point to a command-line flag, or because a
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// validator is already registered for this flag).
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extern GFLAGS_DLL_DECL bool RegisterFlagValidator(const bool* flag, bool (*validate_fn)(const char*, bool));
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extern GFLAGS_DLL_DECL bool RegisterFlagValidator(const int32* flag, bool (*validate_fn)(const char*, int32));
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extern GFLAGS_DLL_DECL bool RegisterFlagValidator(const uint32* flag, bool (*validate_fn)(const char*, uint32));
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extern GFLAGS_DLL_DECL bool RegisterFlagValidator(const int64* flag, bool (*validate_fn)(const char*, int64));
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extern GFLAGS_DLL_DECL bool RegisterFlagValidator(const uint64* flag, bool (*validate_fn)(const char*, uint64));
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extern GFLAGS_DLL_DECL bool RegisterFlagValidator(const double* flag, bool (*validate_fn)(const char*, double));
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extern GFLAGS_DLL_DECL bool RegisterFlagValidator(const std::string* flag, bool (*validate_fn)(const char*, const std::string&));
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// Convenience macro for the registration of a flag validator
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#define DEFINE_validator(name, validator) \
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static const bool name##_validator_registered = \
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GFLAGS_NAMESPACE::RegisterFlagValidator(&FLAGS_##name, validator)
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// --------------------------------------------------------------------
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// These methods are the best way to get access to info about the
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// list of commandline flags. Note that these routines are pretty slow.
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// GetAllFlags: mostly-complete info about the list, sorted by file.
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// ShowUsageWithFlags: pretty-prints the list to stdout (what --help does)
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// ShowUsageWithFlagsRestrict: limit to filenames with restrict as a substr
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// In addition to accessing flags, you can also access argv[0] (the program
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// name) and argv (the entire commandline), which we sock away a copy of.
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// These variables are static, so you should only set them once.
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// No need to export this data only structure from DLL, avoiding VS warning 4251.
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struct CommandLineFlagInfo {
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std::string name; // the name of the flag
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std::string type; // the type of the flag: int32, etc
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std::string description; // the "help text" associated with the flag
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std::string current_value; // the current value, as a string
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std::string default_value; // the default value, as a string
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std::string filename; // 'cleaned' version of filename holding the flag
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bool has_validator_fn; // true if RegisterFlagValidator called on this flag
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bool is_default; // true if the flag has the default value and
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// has not been set explicitly from the cmdline
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// or via SetCommandLineOption
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const void* flag_ptr; // pointer to the flag's current value (i.e. FLAGS_foo)
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// Using this inside of a validator is a recipe for a deadlock.
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// TODO(user) Fix locking when validators are running, to make it safe to
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// call validators during ParseAllFlags.
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// Also make sure then to uncomment the corresponding unit test in
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// gflags_unittest.sh
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extern GFLAGS_DLL_DECL void GetAllFlags(std::vector<CommandLineFlagInfo>* OUTPUT);
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// These two are actually defined in gflags_reporting.cc.
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extern GFLAGS_DLL_DECL void ShowUsageWithFlags(const char *argv0); // what --help does
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extern GFLAGS_DLL_DECL void ShowUsageWithFlagsRestrict(const char *argv0, const char *restrict);
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// Create a descriptive string for a flag.
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// Goes to some trouble to make pretty line breaks.
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extern GFLAGS_DLL_DECL std::string DescribeOneFlag(const CommandLineFlagInfo& flag);
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// Thread-hostile; meant to be called before any threads are spawned.
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extern GFLAGS_DLL_DECL void SetArgv(int argc, const char** argv);
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// The following functions are thread-safe as long as SetArgv() is
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// only called before any threads start.
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extern GFLAGS_DLL_DECL const std::vector<std::string>& GetArgvs();
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extern GFLAGS_DLL_DECL const char* GetArgv(); // all of argv as a string
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extern GFLAGS_DLL_DECL const char* GetArgv0(); // only argv0
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extern GFLAGS_DLL_DECL uint32 GetArgvSum(); // simple checksum of argv
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extern GFLAGS_DLL_DECL const char* ProgramInvocationName(); // argv0, or "UNKNOWN" if not set
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extern GFLAGS_DLL_DECL const char* ProgramInvocationShortName(); // basename(argv0)
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// ProgramUsage() is thread-safe as long as SetUsageMessage() is only
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// called before any threads start.
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extern GFLAGS_DLL_DECL const char* ProgramUsage(); // string set by SetUsageMessage()
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// VersionString() is thread-safe as long as SetVersionString() is only
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// called before any threads start.
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extern GFLAGS_DLL_DECL const char* VersionString(); // string set by SetVersionString()
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// --------------------------------------------------------------------
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// Normally you access commandline flags by just saying "if (FLAGS_foo)"
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// or whatever, and set them by calling "FLAGS_foo = bar" (or, more
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// commonly, via the DEFINE_foo macro). But if you need a bit more
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// control, we have programmatic ways to get/set the flags as well.
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// These programmatic ways to access flags are thread-safe, but direct
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// access is only thread-compatible.
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// Return true iff the flagname was found.
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// OUTPUT is set to the flag's value, or unchanged if we return false.
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extern GFLAGS_DLL_DECL bool GetCommandLineOption(const char* name, std::string* OUTPUT);
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// Return true iff the flagname was found. OUTPUT is set to the flag's
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// CommandLineFlagInfo or unchanged if we return false.
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extern GFLAGS_DLL_DECL bool GetCommandLineFlagInfo(const char* name, CommandLineFlagInfo* OUTPUT);
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// Return the CommandLineFlagInfo of the flagname. exit() if name not found.
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// Example usage, to check if a flag's value is currently the default value:
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// if (GetCommandLineFlagInfoOrDie("foo").is_default) ...
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extern GFLAGS_DLL_DECL CommandLineFlagInfo GetCommandLineFlagInfoOrDie(const char* name);
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enum GFLAGS_DLL_DECL FlagSettingMode {
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// update the flag's value (can call this multiple times).
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// update the flag's value, but *only if* it has not yet been updated
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// with SET_FLAGS_VALUE, SET_FLAG_IF_DEFAULT, or "FLAGS_xxx = nondef".
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// set the flag's default value to this. If the flag has not yet updated
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// yet (via SET_FLAGS_VALUE, SET_FLAG_IF_DEFAULT, or "FLAGS_xxx = nondef")
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// change the flag's current value to the new default value as well.
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// Set a particular flag ("command line option"). Returns a string
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// describing the new value that the option has been set to. The
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// return value API is not well-specified, so basically just depend on
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// it to be empty if the setting failed for some reason -- the name is
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// not a valid flag name, or the value is not a valid value -- and
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// SetCommandLineOption uses set_mode == SET_FLAGS_VALUE (the common case)
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extern GFLAGS_DLL_DECL std::string SetCommandLineOption (const char* name, const char* value);
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extern GFLAGS_DLL_DECL std::string SetCommandLineOptionWithMode(const char* name, const char* value, FlagSettingMode set_mode);
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// --------------------------------------------------------------------
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// Saves the states (value, default value, whether the user has set
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// the flag, registered validators, etc) of all flags, and restores
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// them when the FlagSaver is destroyed. This is very useful in
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// tests, say, when you want to let your tests change the flags, but
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// make sure that they get reverted to the original states when your
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// FLAG_bar = "some value";
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// // test happens here. You can return at any time
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// // without worrying about restoring the FLAG values.
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// Note: This class is marked with GFLAGS_ATTRIBUTE_UNUSED because all
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// the work is done in the constructor and destructor, so in the standard
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// usage example above, the compiler would complain that it's an
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// This class is thread-safe. However, its destructor writes to
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// exactly the set of flags that have changed value during its
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// lifetime, so concurrent _direct_ access to those flags
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// (i.e. FLAGS_foo instead of {Get,Set}CommandLineOption()) is unsafe.
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class GFLAGS_DLL_DECL FlagSaver {
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class FlagSaverImpl* impl_; // we use pimpl here to keep API steady
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FlagSaver(const FlagSaver&); // no copying!
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void operator=(const FlagSaver&);
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}@GFLAGS_ATTRIBUTE_UNUSED@;
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// --------------------------------------------------------------------
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// Some deprecated or hopefully-soon-to-be-deprecated functions.
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// This is often used for logging. TODO(csilvers): figure out a better way
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extern GFLAGS_DLL_DECL std::string CommandlineFlagsIntoString();
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// Usually where this is used, a FlagSaver should be used instead.
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extern GFLAGS_DLL_DECL
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bool ReadFlagsFromString(const std::string& flagfilecontents,
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const char* prog_name,
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bool errors_are_fatal); // uses SET_FLAGS_VALUE
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// These let you manually implement --flagfile functionality.
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extern GFLAGS_DLL_DECL bool AppendFlagsIntoFile(const std::string& filename, const char* prog_name);
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extern GFLAGS_DLL_DECL bool ReadFromFlagsFile(const std::string& filename, const char* prog_name, bool errors_are_fatal); // uses SET_FLAGS_VALUE
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// --------------------------------------------------------------------
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// Useful routines for initializing flags from the environment.
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// In each case, if 'varname' does not exist in the environment
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// return defval. If 'varname' does exist but is not valid
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// (e.g., not a number for an int32 flag), abort with an error.
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// Otherwise, return the value. NOTE: for booleans, for true use
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// 't' or 'T' or 'true' or '1', for false 'f' or 'F' or 'false' or '0'.
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extern GFLAGS_DLL_DECL bool BoolFromEnv(const char *varname, bool defval);
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extern GFLAGS_DLL_DECL int32 Int32FromEnv(const char *varname, int32 defval);
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extern GFLAGS_DLL_DECL uint32 Uint32FromEnv(const char *varname, uint32 defval);
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extern GFLAGS_DLL_DECL int64 Int64FromEnv(const char *varname, int64 defval);
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extern GFLAGS_DLL_DECL uint64 Uint64FromEnv(const char *varname, uint64 defval);
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extern GFLAGS_DLL_DECL double DoubleFromEnv(const char *varname, double defval);
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extern GFLAGS_DLL_DECL const char *StringFromEnv(const char *varname, const char *defval);
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// --------------------------------------------------------------------
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// The next two functions parse gflags from main():
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// Set the "usage" message for this program. For example:
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// string usage("This program does nothing. Sample usage:\n");
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// usage += argv[0] + " <uselessarg1> <uselessarg2>";
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// SetUsageMessage(usage);
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// Do not include commandline flags in the usage: we do that for you!
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// Thread-hostile; meant to be called before any threads are spawned.
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extern GFLAGS_DLL_DECL void SetUsageMessage(const std::string& usage);
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// Sets the version string, which is emitted with --version.
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// For instance: SetVersionString("1.3");
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// Thread-hostile; meant to be called before any threads are spawned.
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extern GFLAGS_DLL_DECL void SetVersionString(const std::string& version);
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// Looks for flags in argv and parses them. Rearranges argv to put
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// flags first, or removes them entirely if remove_flags is true.
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// If a flag is defined more than once in the command line or flag
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// file, the last definition is used. Returns the index (into argv)
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// of the first non-flag argument.
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// See top-of-file for more details on this function.
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#ifndef SWIG // In swig, use ParseCommandLineFlagsScript() instead.
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extern GFLAGS_DLL_DECL uint32 ParseCommandLineFlags(int *argc, char*** argv, bool remove_flags);
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// Calls to ParseCommandLineNonHelpFlags and then to
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// HandleCommandLineHelpFlags can be used instead of a call to
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// ParseCommandLineFlags during initialization, in order to allow for
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// changing default values for some FLAGS (via
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// e.g. SetCommandLineOptionWithMode calls) between the time of
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// command line parsing and the time of dumping help information for
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// the flags as a result of command line parsing. If a flag is
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// defined more than once in the command line or flag file, the last
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// definition is used. Returns the index (into argv) of the first
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// non-flag argument. (If remove_flags is true, will always return 1.)
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extern GFLAGS_DLL_DECL uint32 ParseCommandLineNonHelpFlags(int *argc, char*** argv, bool remove_flags);
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// This is actually defined in gflags_reporting.cc.
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// This function is misnamed (it also handles --version, etc.), but
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// it's too late to change that now. :-(
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extern GFLAGS_DLL_DECL void HandleCommandLineHelpFlags(); // in gflags_reporting.cc
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// Allow command line reparsing. Disables the error normally
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// generated when an unknown flag is found, since it may be found in a
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// later parse. Thread-hostile; meant to be called before any threads
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extern GFLAGS_DLL_DECL void AllowCommandLineReparsing();
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// Reparse the flags that have not yet been recognized. Only flags
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// registered since the last parse will be recognized. Any flag value
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// must be provided as part of the argument using "=", not as a
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// separate command line argument that follows the flag argument.
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// Intended for handling flags from dynamically loaded libraries,
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// since their flags are not registered until they are loaded.
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extern GFLAGS_DLL_DECL void ReparseCommandLineNonHelpFlags();
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// Clean up memory allocated by flags. This is only needed to reduce
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// the quantity of "potentially leaked" reports emitted by memory
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// debugging tools such as valgrind. It is not required for normal
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// operation, or for the google perftools heap-checker. It must only
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// be called when the process is about to exit, and all threads that
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// might access flags are quiescent. Referencing flags after this is
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// called will have unexpected consequences. This is not safe to run
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// when multiple threads might be running: the function is
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extern GFLAGS_DLL_DECL void ShutDownCommandLineFlags();
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// --------------------------------------------------------------------
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// Now come the command line flag declaration/definition macros that
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// will actually be used. They're kind of hairy. A major reason
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// for this is initialization: we want people to be able to access
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// variables in global constructors and have that not crash, even if
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// their global constructor runs before the global constructor here.
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// (Obviously, we can't guarantee the flags will have the correct
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// default value in that case, but at least accessing them is safe.)
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// The only way to do that is have flags point to a static buffer.
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// So we make one, using a union to ensure proper alignment, and
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// then use placement-new to actually set up the flag with the
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// correct default value. In the same vein, we have to worry about
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// flag access in global destructors, so FlagRegisterer has to be
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// careful never to destroy the flag-values it constructs.
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// Note that when we define a flag variable FLAGS_<name>, we also
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// preemptively define a junk variable, FLAGS_no<name>. This is to
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// cause a link-time error if someone tries to define 2 flags with
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// names like "logging" and "nologging". We do this because a bool
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// flag FLAG can be set from the command line to true with a "-FLAG"
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// argument, and to false with a "-noFLAG" argument, and so this can
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// potentially avert confusion.
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// We also put flags into their own namespace. It is purposefully
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// named in an opaque way that people should have trouble typing
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// directly. The idea is that DEFINE puts the flag in the weird
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// namespace, and DECLARE imports the flag from there into the current
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// namespace. The net result is to force people to use DECLARE to get
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// access to a flag, rather than saying "extern GFLAGS_DLL_DECL bool FLAGS_whatever;"
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// or some such instead. We want this so we can put extra
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// functionality (like sanity-checking) in DECLARE if we want, and
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// make sure it is picked up everywhere.
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// We also put the type of the variable in the namespace, so that
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// people can't DECLARE_int32 something that they DEFINE_bool'd
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class GFLAGS_DLL_DECL FlagRegisterer {
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// We instantiate this template ctor for all supported types,
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// so it is possible to place implementation of the FlagRegisterer ctor in
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// Calling this constructor with unsupported type will produce linker error.
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template <typename FlagType>
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FlagRegisterer(const char* name,
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const char* help, const char* filename,
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FlagType* current_storage, FlagType* defvalue_storage);
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// If your application #defines STRIP_FLAG_HELP to a non-zero value
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// before #including this file, we remove the help message from the
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// binary file. This can reduce the size of the resulting binary
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// somewhat, and may also be useful for security reasons.
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extern GFLAGS_DLL_DECL const char kStrippedFlagHelp[];
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} // namespace GFLAGS_NAMESPACE
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#ifndef SWIG // In swig, ignore the main flag declarations
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#if defined(STRIP_FLAG_HELP) && STRIP_FLAG_HELP > 0
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// Need this construct to avoid the 'defined but not used' warning.
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#define MAYBE_STRIPPED_HELP(txt) \
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(false ? (txt) : GFLAGS_NAMESPACE::kStrippedFlagHelp)
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#define MAYBE_STRIPPED_HELP(txt) txt
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// Each command-line flag has two variables associated with it: one
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// with the current value, and one with the default value. However,
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// we have a third variable, which is where value is assigned; it's a
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// constant. This guarantees that FLAG_##value is initialized at
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// static initialization time (e.g. before program-start) rather than
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// than global construction time (which is after program-start but
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// before main), at least when 'value' is a compile-time constant. We
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// use a small trick for the "default value" variable, and call it
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// FLAGS_no<name>. This serves the second purpose of assuring a
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// compile error if someone tries to define a flag named no<name>
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// which is illegal (--foo and --nofoo both affect the "foo" flag).
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#define DEFINE_VARIABLE(type, shorttype, name, value, help) \
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namespace fL##shorttype { \
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static const type FLAGS_nono##name = value; \
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/* We always want to export defined variables, dll or no */ \
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GFLAGS_DLL_DEFINE_FLAG type FLAGS_##name = FLAGS_nono##name; \
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type FLAGS_no##name = FLAGS_nono##name; \
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static GFLAGS_NAMESPACE::FlagRegisterer o_##name( \
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#name, MAYBE_STRIPPED_HELP(help), __FILE__, \
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&FLAGS_##name, &FLAGS_no##name); \
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using fL##shorttype::FLAGS_##name
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// For DEFINE_bool, we want to do the extra check that the passed-in
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// value is actually a bool, and not a string or something that can be
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// coerced to a bool. These declarations (no definition needed!) will
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// help us do that, and never evaluate From, which is important.
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// We'll use 'sizeof(IsBool(val))' to distinguish. This code requires
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// that the compiler have different sizes for bool & double. Since
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// this is not guaranteed by the standard, we check it with a
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struct CompileAssert {};
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typedef CompileAssert expected_sizeof_double_neq_sizeof_bool[
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(sizeof(double) != sizeof(bool)) ? 1 : -1];
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template<typename From> double GFLAGS_DLL_DECL IsBoolFlag(const From& from);
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GFLAGS_DLL_DECL bool IsBoolFlag(bool from);
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// Here are the actual DEFINE_*-macros. The respective DECLARE_*-macros
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// are in a separate include, gflags_declare.h, for reducing
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// the physical transitive size for DECLARE use.
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#define DEFINE_bool(name, val, txt) \
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typedef ::fLB::CompileAssert FLAG_##name##_value_is_not_a_bool[ \
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(sizeof(::fLB::IsBoolFlag(val)) != sizeof(double))? 1: -1]; \
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DEFINE_VARIABLE(bool, B, name, val, txt)
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#define DEFINE_int32(name, val, txt) \
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DEFINE_VARIABLE(GFLAGS_NAMESPACE::int32, I, \
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#define DEFINE_uint32(name,val, txt) \
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DEFINE_VARIABLE(GFLAGS_NAMESPACE::uint32, U, \
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#define DEFINE_int64(name, val, txt) \
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DEFINE_VARIABLE(GFLAGS_NAMESPACE::int64, I64, \
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#define DEFINE_uint64(name,val, txt) \
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DEFINE_VARIABLE(GFLAGS_NAMESPACE::uint64, U64, \
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#define DEFINE_double(name, val, txt) \
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DEFINE_VARIABLE(double, D, name, val, txt)
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// Strings are trickier, because they're not a POD, so we can't
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// construct them at static-initialization time (instead they get
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// constructed at global-constructor time, which is much later). To
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// try to avoid crashes in that case, we use a char buffer to store
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// the string, which we can static-initialize, and then placement-new
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// into it later. It's not perfect, but the best we can do.
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inline clstring* dont_pass0toDEFINE_string(char *stringspot,
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return new(stringspot) clstring(value);
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inline clstring* dont_pass0toDEFINE_string(char *stringspot,
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const clstring &value) {
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return new(stringspot) clstring(value);
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inline clstring* dont_pass0toDEFINE_string(char *stringspot,
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// Auxiliary class used to explicitly call destructor of string objects
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// allocated using placement new during static program deinitialization.
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// The destructor MUST be an inline function such that the explicit
556
// destruction occurs in the same compilation unit as the placement new.
557
class StringFlagDestructor {
558
void *current_storage_;
559
void *defvalue_storage_;
563
StringFlagDestructor(void *current, void *defvalue)
564
: current_storage_(current), defvalue_storage_(defvalue) {}
566
~StringFlagDestructor() {
567
reinterpret_cast<clstring*>(current_storage_ )->~clstring();
568
reinterpret_cast<clstring*>(defvalue_storage_)->~clstring();
574
// We need to define a var named FLAGS_no##name so people don't define
575
// --string and --nostring. And we need a temporary place to put val
576
// so we don't have to evaluate it twice. Two great needs that go
578
// The weird 'using' + 'extern' inside the fLS namespace is to work around
579
// an unknown compiler bug/issue with the gcc 4.2.1 on SUSE 10. See
580
// http://code.google.com/p/google-gflags/issues/detail?id=20
581
#define DEFINE_string(name, val, txt) \
583
using ::fLS::clstring; \
584
using ::fLS::StringFlagDestructor; \
585
static union { void* align; char s[sizeof(clstring)]; } s_##name[2]; \
586
clstring* const FLAGS_no##name = ::fLS:: \
587
dont_pass0toDEFINE_string(s_##name[0].s, \
589
static GFLAGS_NAMESPACE::FlagRegisterer o_##name( \
590
#name, MAYBE_STRIPPED_HELP(txt), __FILE__, \
591
FLAGS_no##name, new (s_##name[1].s) clstring(*FLAGS_no##name)); \
592
static StringFlagDestructor d_##name(s_##name[0].s, s_##name[1].s); \
593
extern GFLAGS_DLL_DEFINE_FLAG clstring& FLAGS_##name; \
594
using fLS::FLAGS_##name; \
595
clstring& FLAGS_##name = *FLAGS_no##name; \
597
using fLS::FLAGS_##name
602
@INCLUDE_GFLAGS_NS_H@
605
#endif // GFLAGS_GFLAGS_H_
added
removed
etc/samples/thirdparty/gflags/src/gflags.h.in
