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diff --git a/boost/interprocess/sync/posix/semaphore_wrapper.hpp b/boost/interprocess/sync/posix/semaphore_wrapper.hpp
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+//////////////////////////////////////////////////////////////////////////////
+//
+// (C) Copyright Ion Gaztanaga 2005-2011. Distributed under the Boost
+// Software License, Version 1.0. (See accompanying file
+// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+// See http://www.boost.org/libs/interprocess for documentation.
+//
+//////////////////////////////////////////////////////////////////////////////
+
+#ifndef BOOST_INTERPROCESS_POSIX_SEMAPHORE_WRAPPER_HPP
+#define BOOST_INTERPROCESS_POSIX_SEMAPHORE_WRAPPER_HPP
+
+#include <boost/interprocess/detail/posix_time_types_wrk.hpp>
+#include <boost/interprocess/exceptions.hpp>
+#include <boost/interprocess/creation_tags.hpp>
+#include <boost/interprocess/detail/os_file_functions.hpp>
+#include <boost/interprocess/detail/tmp_dir_helpers.hpp>
+#include <boost/interprocess/permissions.hpp>
+
+#include <fcntl.h> //O_CREAT, O_*...
+#include <unistd.h> //close
+#include <string> //std::string
+#include <semaphore.h> //sem_* family, SEM_VALUE_MAX
+#include <sys/stat.h> //mode_t, S_IRWXG, S_IRWXO, S_IRWXU,
+#include <boost/assert.hpp>
+
+#ifdef SEM_FAILED
+#define BOOST_INTERPROCESS_POSIX_SEM_FAILED (reinterpret_cast<sem_t*>(SEM_FAILED))
+#else
+#define BOOST_INTERPROCESS_POSIX_SEM_FAILED (reinterpret_cast<sem_t*>(-1))
+#endif
+
+#ifdef BOOST_INTERPROCESS_POSIX_TIMEOUTS
+#include <boost/interprocess/sync/posix/ptime_to_timespec.hpp>
+#else
+#include <boost/interprocess/detail/os_thread_functions.hpp>
+#endif
+
+namespace boost {
+namespace interprocess {
+namespace ipcdetail {
+
+inline bool semaphore_open
+ (sem_t *&handle, create_enum_t type, const char *origname,
+ unsigned int count = 0, const permissions &perm = permissions())
+{
+ std::string name;
+ #ifndef BOOST_INTERPROCESS_FILESYSTEM_BASED_POSIX_SEMAPHORES
+ add_leading_slash(origname, name);
+ #else
+ create_tmp_and_clean_old_and_get_filename(origname, name);
+ #endif
+
+ //Create new mapping
+ int oflag = 0;
+ switch(type){
+ case DoOpen:
+ {
+ //No addition
+ handle = ::sem_open(name.c_str(), oflag);
+ }
+ break;
+ case DoOpenOrCreate:
+ case DoCreate:
+ {
+ while(1){
+ oflag = (O_CREAT | O_EXCL);
+ handle = ::sem_open(name.c_str(), oflag, perm.get_permissions(), count);
+ if(handle != BOOST_INTERPROCESS_POSIX_SEM_FAILED){
+ //We can't change semaphore permissions!
+ //::fchmod(handle, perm.get_permissions());
+ break;
+ }
+ else if(errno == EEXIST && type == DoOpenOrCreate){
+ oflag = 0;
+ if( (handle = ::sem_open(name.c_str(), oflag)) != BOOST_INTERPROCESS_POSIX_SEM_FAILED
+ || (errno != ENOENT) ){
+ break;
+ }
+ }
+ else{
+ break;
+ }
+ }
+ }
+ break;
+ default:
+ {
+ error_info err(other_error);
+ throw interprocess_exception(err);
+ }
+ }
+
+ //Check for error
+ if(handle == BOOST_INTERPROCESS_POSIX_SEM_FAILED){
+ throw interprocess_exception(error_info(errno));
+ }
+
+ return true;
+}
+
+inline void semaphore_close(sem_t *handle)
+{
+ int ret = sem_close(handle);
+ if(ret != 0){
+ BOOST_ASSERT(0);
+ }
+}
+
+inline bool semaphore_unlink(const char *semname)
+{
+ try{
+ std::string sem_str;
+ #ifndef BOOST_INTERPROCESS_FILESYSTEM_BASED_POSIX_SEMAPHORES
+ add_leading_slash(semname, sem_str);
+ #else
+ tmp_filename(semname, sem_str);
+ #endif
+ return 0 == sem_unlink(sem_str.c_str());
+ }
+ catch(...){
+ return false;
+ }
+}
+
+inline void semaphore_init(sem_t *handle, unsigned int initialCount)
+{
+ int ret = sem_init(handle, 1, initialCount);
+ //According to SUSV3 version 2003 edition, the return value of a successful
+ //sem_init call is not defined, but -1 is returned on failure.
+ //In the future, a successful call might be required to return 0.
+ if(ret == -1){
+ throw interprocess_exception(system_error_code());
+ }
+}
+
+inline void semaphore_destroy(sem_t *handle)
+{
+ int ret = sem_destroy(handle);
+ if(ret != 0){
+ BOOST_ASSERT(0);
+ }
+}
+
+inline void semaphore_post(sem_t *handle)
+{
+ int ret = sem_post(handle);
+ if(ret != 0){
+ throw interprocess_exception(system_error_code());
+ }
+}
+
+inline void semaphore_wait(sem_t *handle)
+{
+ int ret = sem_wait(handle);
+ if(ret != 0){
+ throw interprocess_exception(system_error_code());
+ }
+}
+
+inline bool semaphore_try_wait(sem_t *handle)
+{
+ int res = sem_trywait(handle);
+ if(res == 0)
+ return true;
+ if(system_error_code() == EAGAIN){
+ return false;
+ }
+ throw interprocess_exception(system_error_code());
+ return false;
+}
+
+inline bool semaphore_timed_wait(sem_t *handle, const boost::posix_time::ptime &abs_time)
+{
+ if(abs_time == boost::posix_time::pos_infin){
+ semaphore_wait(handle);
+ return true;
+ }
+ #ifdef BOOST_INTERPROCESS_POSIX_TIMEOUTS
+ timespec tspec = ptime_to_timespec(abs_time);
+ for (;;){
+ int res = sem_timedwait(handle, &tspec);
+ if(res == 0)
+ return true;
+ if (res > 0){
+ //buggy glibc, copy the returned error code to errno
+ errno = res;
+ }
+ if(system_error_code() == ETIMEDOUT){
+ return false;
+ }
+ throw interprocess_exception(system_error_code());
+ }
+ return false;
+ #else //#ifdef BOOST_INTERPROCESS_POSIX_TIMEOUTS
+ boost::posix_time::ptime now;
+ do{
+ if(semaphore_try_wait(handle))
+ return true;
+ thread_yield();
+ }while((now = microsec_clock::universal_time()) < abs_time);
+ return false;
+ #endif //#ifdef BOOST_INTERPROCESS_POSIX_TIMEOUTS
+}
+
+} //namespace ipcdetail {
+} //namespace interprocess {
+} //namespace boost {
+
+#endif //#ifndef BOOST_INTERPROCESS_POSIX_SEMAPHORE_WRAPPER_HPP