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Diffstat (limited to 'server-tools/instance-manager/thread_repository.h')
| -rw-r--r-- | server-tools/instance-manager/thread_repository.h | 113 |
1 files changed, 0 insertions, 113 deletions
diff --git a/server-tools/instance-manager/thread_repository.h b/server-tools/instance-manager/thread_repository.h deleted file mode 100644 index 7bd21d66e3d..00000000000 --- a/server-tools/instance-manager/thread_repository.h +++ /dev/null @@ -1,113 +0,0 @@ -#ifndef INCLUDES_MYSQL_INSTANCE_MANAGER_THREAD_REPOSITORY_HH -#define INCLUDES_MYSQL_INSTANCE_MANAGER_THREAD_REPOSITORY_HH -/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB - - This program is free software; you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 2 of the License, or - (at your option) any later version. - - This program is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU General Public License for more details. - - You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software - Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ - -/* - A multi-threaded application shall nicely work with signals. - - This means it shall, first of all, shut down nicely on ``quit'' signals: - stop all running threads, cleanup and exit. - - Note, that a thread can't be shut down nicely if it doesn't want to be. - That's why to perform clean shutdown, all threads consituting a process - must observe certain rules. Here we use the rules, described in Butenhof - book 'Programming with POSIX threads', namely: - - all user signals are handled in 'signal thread' in synchronous manner - (by means of sigwait). To guarantee that the signal thread is the only who - can receive user signals, all threads block them, and signal thread is - the only who calls sigwait() with an apporpriate sigmask. - To propogate a signal to the workers the signal thread sets - a variable, corresponding to the signal. Additionally the signal thread - sends each worker an internal signal (by means of pthread_kill) to kick it - out from possible blocking syscall, and possibly pthread_cond_signal if - some thread is blocked in pthread_cond_[timed]wait. - - a worker handles only internal 'kick' signal (the handler does nothing). - In case when a syscall returns 'EINTR' the worker checks all - signal-related variables and behaves accordingly. - Also these variables shall be checked from time to time in long - CPU-bounded operations, and before/after pthread_cond_wait. (It's supposed - that a worker thread either waits in a syscall/conditional variable, or - computes something.) - - to guarantee signal deliverence, there should be some kind of feedback, - e. g. all workers shall account in the signal thread Thread Repository and - unregister from it on exit. - - Configuration reload (on SIGHUP) and thread timeouts/alarms can be handled - in manner, similar to ``quit'' signals. -*/ - -#ifdef __GNUC__ -#pragma interface -#endif - -#include <my_global.h> -#include <my_pthread.h> - - -/* - Thread_info - repository entry for each worker thread - All entries comprise double-linked list like: - 0 -- entry -- entry -- entry - 0 - Double-linked list is used to unregister threads easy. -*/ - -class Thread_info -{ - pthread_cond_t *current_cond; - Thread_info *prev, *next; - pthread_t thread_id; - Thread_info() {} - friend class Thread_repository; -public: - Thread_info(pthread_t thread_id_arg) : thread_id(thread_id_arg) {} -}; - - -/* - Thread_repository - contains handles for each worker thread to deliver - signal information to workers. -*/ - -class Thread_repository -{ -public: - Thread_repository(); - ~Thread_repository(); - - void register_thread(Thread_info *info); - void unregister_thread(Thread_info *info); - void deliver_shutdown(); - inline bool is_shutdown(); - int cond_wait(Thread_info *info, pthread_cond_t *cond, - pthread_mutex_t *mutex, bool *is_shutdown); -private: - Thread_info head; - bool shutdown_in_progress; - pthread_mutex_t LOCK_thread_repository; - pthread_cond_t COND_thread_repository_is_empty; -}; - - -inline bool Thread_repository::is_shutdown() -{ - pthread_mutex_lock(&LOCK_thread_repository); - bool res= shutdown_in_progress; - pthread_mutex_unlock(&LOCK_thread_repository); - return res; -} - -#endif // INCLUDES_MYSQL_INSTANCE_MANAGER_THREAD_REPOSITORY_HH |