diff options
Diffstat (limited to 'src/base')
| -rw-r--r-- | src/base/commandlineflags.h | 133 | ||||
| -rw-r--r-- | src/base/googleinit.h | 51 | ||||
| -rw-r--r-- | src/base/mutex.h | 333 |
3 files changed, 517 insertions, 0 deletions
diff --git a/src/base/commandlineflags.h b/src/base/commandlineflags.h new file mode 100644 index 000000000000..c8d50890269a --- /dev/null +++ b/src/base/commandlineflags.h @@ -0,0 +1,133 @@ +// Copyright (c) 2008, Google Inc. +// All rights reserved. +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following disclaimer +// in the documentation and/or other materials provided with the +// distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived from +// this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +// --- +// This file is a compatibility layer that defines Google's version of +// command line flags that are used for configuration. +// +// We put flags into their own namespace. It is purposefully +// named in an opaque way that people should have trouble typing +// directly. The idea is that DEFINE puts the flag in the weird +// namespace, and DECLARE imports the flag from there into the +// current namespace. The net result is to force people to use +// DECLARE to get access to a flag, rather than saying +// extern bool FLAGS_logtostderr; +// or some such instead. We want this so we can put extra +// functionality (like sanity-checking) in DECLARE if we want, +// and make sure it is picked up everywhere. +// +// We also put the type of the variable in the namespace, so that +// people can't DECLARE_int32 something that they DEFINE_bool'd +// elsewhere. +#ifndef BASE_COMMANDLINEFLAGS_H__ +#define BASE_COMMANDLINEFLAGS_H__ + +#include "config.h" +#include <string> +#include <string.h> // for memchr +#include <stdlib.h> // for getenv + +#ifdef HAVE_LIB_GFLAGS + +#include <gflags/gflags.h> + +#else + +#include "glog/logging.h" + +#define DECLARE_VARIABLE(type, shorttype, name, tn) \ + namespace fL##shorttype { \ + extern GOOGLE_GLOG_DLL_DECL type FLAGS_##name; \ + } \ + using fL##shorttype::FLAGS_##name +#define DEFINE_VARIABLE(type, shorttype, name, value, meaning, tn) \ + namespace fL##shorttype { \ + GOOGLE_GLOG_DLL_DECL type FLAGS_##name(value); \ + char FLAGS_no##name; \ + } \ + using fL##shorttype::FLAGS_##name + +// bool specialization +#define DECLARE_bool(name) \ + DECLARE_VARIABLE(bool, B, name, bool) +#define DEFINE_bool(name, value, meaning) \ + DEFINE_VARIABLE(bool, B, name, value, meaning, bool) + +// int32 specialization +#define DECLARE_int32(name) \ + DECLARE_VARIABLE(GOOGLE_NAMESPACE::int32, I, name, int32) +#define DEFINE_int32(name, value, meaning) \ + DEFINE_VARIABLE(GOOGLE_NAMESPACE::int32, I, name, value, meaning, int32) + +// Special case for string, because we have to specify the namespace +// std::string, which doesn't play nicely with our FLAG__namespace hackery. +#define DECLARE_string(name) \ + namespace fLS { \ + extern GOOGLE_GLOG_DLL_DECL std::string& FLAGS_##name; \ + } \ + using fLS::FLAGS_##name +#define DEFINE_string(name, value, meaning) \ + namespace fLS { \ + std::string FLAGS_##name##_buf(value); \ + GOOGLE_GLOG_DLL_DECL std::string& FLAGS_##name = FLAGS_##name##_buf; \ + char FLAGS_no##name; \ + } \ + using fLS::FLAGS_##name + +#endif // HAVE_LIB_GFLAGS + +// Define GLOG_DEFINE_* using DEFINE_* . By using these macros, we +// have GLOG_* environ variables even if we have gflags installed. +// +// If both an environment variable and a flag are specified, the value +// specified by a flag wins. E.g., if GLOG_v=0 and --v=1, the +// verbosity will be 1, not 0. + +#define GLOG_DEFINE_bool(name, value, meaning) \ + DEFINE_bool(name, EnvToBool("GLOG_" #name, value), meaning) + +#define GLOG_DEFINE_int32(name, value, meaning) \ + DEFINE_int32(name, EnvToInt("GLOG_" #name, value), meaning) + +#define GLOG_DEFINE_string(name, value, meaning) \ + DEFINE_string(name, EnvToString("GLOG_" #name, value), meaning) + +// These macros (could be functions, but I don't want to bother with a .cc +// file), make it easier to initialize flags from the environment. + +#define EnvToString(envname, dflt) \ + (!getenv(envname) ? (dflt) : getenv(envname)) + +#define EnvToBool(envname, dflt) \ + (!getenv(envname) ? (dflt) : memchr("tTyY1\0", getenv(envname)[0], 6) != NULL) + +#define EnvToInt(envname, dflt) \ + (!getenv(envname) ? (dflt) : strtol(getenv(envname), NULL, 10)) + +#endif // BASE_COMMANDLINEFLAGS_H__ diff --git a/src/base/googleinit.h b/src/base/googleinit.h new file mode 100644 index 000000000000..5a8b515cd604 --- /dev/null +++ b/src/base/googleinit.h @@ -0,0 +1,51 @@ +// Copyright (c) 2008, Google Inc. +// All rights reserved. +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following disclaimer +// in the documentation and/or other materials provided with the +// distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived from +// this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +// --- +// Author: Jacob Hoffman-Andrews + +#ifndef _GOOGLEINIT_H +#define _GOOGLEINIT_H + +class GoogleInitializer { + public: + typedef void (*void_function)(void); + GoogleInitializer(const char*, void_function f) { + f(); + } +}; + +#define REGISTER_MODULE_INITIALIZER(name, body) \ + namespace { \ + static void google_init_module_##name () { body; } \ + GoogleInitializer google_initializer_module_##name(#name, \ + google_init_module_##name); \ + } + +#endif /* _GOOGLEINIT_H */ diff --git a/src/base/mutex.h b/src/base/mutex.h new file mode 100644 index 000000000000..ced2b9950edc --- /dev/null +++ b/src/base/mutex.h @@ -0,0 +1,333 @@ +// Copyright (c) 2007, Google Inc. +// All rights reserved. +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following disclaimer +// in the documentation and/or other materials provided with the +// distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived from +// this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +// +// --- +// Author: Craig Silverstein. +// +// A simple mutex wrapper, supporting locks and read-write locks. +// You should assume the locks are *not* re-entrant. +// +// To use: you should define the following macros in your configure.ac: +// ACX_PTHREAD +// AC_RWLOCK +// The latter is defined in ../autoconf. +// +// This class is meant to be internal-only and should be wrapped by an +// internal namespace. Before you use this module, please give the +// name of your internal namespace for this module. Or, if you want +// to expose it, you'll want to move it to the Google namespace. We +// cannot put this class in global namespace because there can be some +// problems when we have multiple versions of Mutex in each shared object. +// +// NOTE: by default, we have #ifdef'ed out the TryLock() method. +// This is for two reasons: +// 1) TryLock() under Windows is a bit annoying (it requires a +// #define to be defined very early). +// 2) TryLock() is broken for NO_THREADS mode, at least in NDEBUG +// mode. +// If you need TryLock(), and either these two caveats are not a +// problem for you, or you're willing to work around them, then +// feel free to #define GMUTEX_TRYLOCK, or to remove the #ifdefs +// in the code below. +// +// CYGWIN NOTE: Cygwin support for rwlock seems to be buggy: +// http://www.cygwin.com/ml/cygwin/2008-12/msg00017.html +// Because of that, we might as well use windows locks for +// cygwin. They seem to be more reliable than the cygwin pthreads layer. +// +// TRICKY IMPLEMENTATION NOTE: +// This class is designed to be safe to use during +// dynamic-initialization -- that is, by global constructors that are +// run before main() starts. The issue in this case is that +// dynamic-initialization happens in an unpredictable order, and it +// could be that someone else's dynamic initializer could call a +// function that tries to acquire this mutex -- but that all happens +// before this mutex's constructor has run. (This can happen even if +// the mutex and the function that uses the mutex are in the same .cc +// file.) Basically, because Mutex does non-trivial work in its +// constructor, it's not, in the naive implementation, safe to use +// before dynamic initialization has run on it. +// +// The solution used here is to pair the actual mutex primitive with a +// bool that is set to true when the mutex is dynamically initialized. +// (Before that it's false.) Then we modify all mutex routines to +// look at the bool, and not try to lock/unlock until the bool makes +// it to true (which happens after the Mutex constructor has run.) +// +// This works because before main() starts -- particularly, during +// dynamic initialization -- there are no threads, so a) it's ok that +// the mutex operations are a no-op, since we don't need locking then +// anyway; and b) we can be quite confident our bool won't change +// state between a call to Lock() and a call to Unlock() (that would +// require a global constructor in one translation unit to call Lock() +// and another global constructor in another translation unit to call +// Unlock() later, which is pretty perverse). +// +// That said, it's tricky, and can conceivably fail; it's safest to +// avoid trying to acquire a mutex in a global constructor, if you +// can. One way it can fail is that a really smart compiler might +// initialize the bool to true at static-initialization time (too +// early) rather than at dynamic-initialization time. To discourage +// that, we set is_safe_ to true in code (not the constructor +// colon-initializer) and set it to true via a function that always +// evaluates to true, but that the compiler can't know always +// evaluates to true. This should be good enough. + +#ifndef GOOGLE_MUTEX_H_ +#define GOOGLE_MUTEX_H_ + +#include "config.h" // to figure out pthreads support + +#if defined(NO_THREADS) + typedef int MutexType; // to keep a lock-count +#elif defined(_WIN32) || defined(__CYGWIN32__) || defined(__CYGWIN64__) +# ifndef WIN32_LEAN_AND_MEAN +# define WIN32_LEAN_AND_MEAN // We only need minimal includes +# endif +# ifdef GMUTEX_TRYLOCK + // We need Windows NT or later for TryEnterCriticalSection(). If you + // don't need that functionality, you can remove these _WIN32_WINNT + // lines, and change TryLock() to assert(0) or something. +# ifndef _WIN32_WINNT +# define _WIN32_WINNT 0x0400 +# endif +# endif +// To avoid macro definition of ERROR. +# ifndef NOGDI +# define NOGDI +# endif +// To avoid macro definition of min/max. +# ifndef NOMINMAX +# define NOMINMAX +# endif +# include <windows.h> + typedef CRITICAL_SECTION MutexType; +#elif defined(HAVE_PTHREAD) && defined(HAVE_RWLOCK) + // Needed for pthread_rwlock_*. If it causes problems, you could take it + // out, but then you'd have to unset HAVE_RWLOCK (at least on linux -- it + // *does* cause problems for FreeBSD, or MacOSX, but isn't needed + // for locking there.) +# ifdef __linux__ +# ifndef _XOPEN_SOURCE // Some other header might have already set it for us. +# define _XOPEN_SOURCE 500 // may be needed to get the rwlock calls +# endif +# endif +# include <pthread.h> + typedef pthread_rwlock_t MutexType; +#elif defined(HAVE_PTHREAD) +# include <pthread.h> + typedef pthread_mutex_t MutexType; +#else +# error Need to implement mutex.h for your architecture, or #define NO_THREADS +#endif + +// We need to include these header files after defining _XOPEN_SOURCE +// as they may define the _XOPEN_SOURCE macro. +#include <assert.h> +#include <stdlib.h> // for abort() + +#define MUTEX_NAMESPACE glog_internal_namespace_ + +namespace MUTEX_NAMESPACE { + +class Mutex { + public: + // Create a Mutex that is not held by anybody. This constructor is + // typically used for Mutexes allocated on the heap or the stack. + // See below for a recommendation for constructing global Mutex + // objects. + inline Mutex(); + + // Destructor + inline ~Mutex(); + + inline void Lock(); // Block if needed until free then acquire exclusively + inline void Unlock(); // Release a lock acquired via Lock() +#ifdef GMUTEX_TRYLOCK + inline bool TryLock(); // If free, Lock() and return true, else return false +#endif + // Note that on systems that don't support read-write locks, these may + // be implemented as synonyms to Lock() and Unlock(). So you can use + // these for efficiency, but don't use them anyplace where being able + // to do shared reads is necessary to avoid deadlock. + inline void ReaderLock(); // Block until free or shared then acquire a share + inline void ReaderUnlock(); // Release a read share of this Mutex + inline void WriterLock() { Lock(); } // Acquire an exclusive lock + inline void WriterUnlock() { Unlock(); } // Release a lock from WriterLock() + + // TODO(hamaji): Do nothing, implement correctly. + inline void AssertHeld() {} + + private: + MutexType mutex_; + // We want to make sure that the compiler sets is_safe_ to true only + // when we tell it to, and never makes assumptions is_safe_ is + // always true. volatile is the most reliable way to do that. + volatile bool is_safe_; + + inline void SetIsSafe() { is_safe_ = true; } + + // Catch the error of writing Mutex when intending MutexLock. + Mutex(Mutex* /*ignored*/) {} + // Disallow "evil" constructors + Mutex(const Mutex&); + void operator=(const Mutex&); +}; + +// Now the implementation of Mutex for various systems +#if defined(NO_THREADS) + +// When we don't have threads, we can be either reading or writing, +// but not both. We can have lots of readers at once (in no-threads +// mode, that's most likely to happen in recursive function calls), +// but only one writer. We represent this by having mutex_ be -1 when +// writing and a number > 0 when reading (and 0 when no lock is held). +// +// In debug mode, we assert these invariants, while in non-debug mode +// we do nothing, for efficiency. That's why everything is in an +// assert. + +Mutex::Mutex() : mutex_(0) { } +Mutex::~Mutex() { assert(mutex_ == 0); } +void Mutex::Lock() { assert(--mutex_ == -1); } +void Mutex::Unlock() { assert(mutex_++ == -1); } +#ifdef GMUTEX_TRYLOCK +bool Mutex::TryLock() { if (mutex_) return false; Lock(); return true; } +#endif +void Mutex::ReaderLock() { assert(++mutex_ > 0); } +void Mutex::ReaderUnlock() { assert(mutex_-- > 0); } + +#elif defined(_WIN32) || defined(__CYGWIN32__) || defined(__CYGWIN64__) + +Mutex::Mutex() { InitializeCriticalSection(&mutex_); SetIsSafe(); } +Mutex::~Mutex() { DeleteCriticalSection(&mutex_); } +void Mutex::Lock() { if (is_safe_) EnterCriticalSection(&mutex_); } +void Mutex::Unlock() { if (is_safe_) LeaveCriticalSection(&mutex_); } +#ifdef GMUTEX_TRYLOCK +bool Mutex::TryLock() { return is_safe_ ? + TryEnterCriticalSection(&mutex_) != 0 : true; } +#endif +void Mutex::ReaderLock() { Lock(); } // we don't have read-write locks +void Mutex::ReaderUnlock() { Unlock(); } + +#elif defined(HAVE_PTHREAD) && defined(HAVE_RWLOCK) + +#define SAFE_PTHREAD(fncall) do { /* run fncall if is_safe_ is true */ \ + if (is_safe_ && fncall(&mutex_) != 0) abort(); \ +} while (0) + +Mutex::Mutex() { + SetIsSafe(); + if (is_safe_ && pthread_rwlock_init(&mutex_, NULL) != 0) abort(); +} +Mutex::~Mutex() { SAFE_PTHREAD(pthread_rwlock_destroy); } +void Mutex::Lock() { SAFE_PTHREAD(pthread_rwlock_wrlock); } +void Mutex::Unlock() { SAFE_PTHREAD(pthread_rwlock_unlock); } +#ifdef GMUTEX_TRYLOCK +bool Mutex::TryLock() { return is_safe_ ? + pthread_rwlock_trywrlock(&mutex_) == 0 : + true; } +#endif +void Mutex::ReaderLock() { SAFE_PTHREAD(pthread_rwlock_rdlock); } +void Mutex::ReaderUnlock() { SAFE_PTHREAD(pthread_rwlock_unlock); } +#undef SAFE_PTHREAD + +#elif defined(HAVE_PTHREAD) + +#define SAFE_PTHREAD(fncall) do { /* run fncall if is_safe_ is true */ \ + if (is_safe_ && fncall(&mutex_) != 0) abort(); \ +} while (0) + +Mutex::Mutex() { + SetIsSafe(); + if (is_safe_ && pthread_mutex_init(&mutex_, NULL) != 0) abort(); +} +Mutex::~Mutex() { SAFE_PTHREAD(pthread_mutex_destroy); } +void Mutex::Lock() { SAFE_PTHREAD(pthread_mutex_lock); } +void Mutex::Unlock() { SAFE_PTHREAD(pthread_mutex_unlock); } +#ifdef GMUTEX_TRYLOCK +bool Mutex::TryLock() { return is_safe_ ? + pthread_mutex_trylock(&mutex_) == 0 : true; } +#endif +void Mutex::ReaderLock() { Lock(); } +void Mutex::ReaderUnlock() { Unlock(); } +#undef SAFE_PTHREAD + +#endif + +// -------------------------------------------------------------------------- +// Some helper classes + +// MutexLock(mu) acquires mu when constructed and releases it when destroyed. +class MutexLock { + public: + explicit MutexLock(Mutex *mu) : mu_(mu) { mu_->Lock(); } + ~MutexLock() { mu_->Unlock(); } + private: + Mutex * const mu_; + // Disallow "evil" constructors + MutexLock(const MutexLock&); + void operator=(const MutexLock&); +}; + +// ReaderMutexLock and WriterMutexLock do the same, for rwlocks +class ReaderMutexLock { + public: + explicit ReaderMutexLock(Mutex *mu) : mu_(mu) { mu_->ReaderLock(); } + ~ReaderMutexLock() { mu_->ReaderUnlock(); } + private: + Mutex * const mu_; + // Disallow "evil" constructors + ReaderMutexLock(const ReaderMutexLock&); + void operator=(const ReaderMutexLock&); +}; + +class WriterMutexLock { + public: + explicit WriterMutexLock(Mutex *mu) : mu_(mu) { mu_->WriterLock(); } + ~WriterMutexLock() { mu_->WriterUnlock(); } + private: + Mutex * const mu_; + // Disallow "evil" constructors + WriterMutexLock(const WriterMutexLock&); + void operator=(const WriterMutexLock&); +}; + +// Catch bug where variable name is omitted, e.g. MutexLock (&mu); +#define MutexLock(x) COMPILE_ASSERT(0, mutex_lock_decl_missing_var_name) +#define ReaderMutexLock(x) COMPILE_ASSERT(0, rmutex_lock_decl_missing_var_name) +#define WriterMutexLock(x) COMPILE_ASSERT(0, wmutex_lock_decl_missing_var_name) + +} // namespace MUTEX_NAMESPACE + +using namespace MUTEX_NAMESPACE; + +#undef MUTEX_NAMESPACE + +#endif /* #define GOOGLE_MUTEX_H__ */ |