+++ /dev/null
-/*
- * Thread handling stuff for Citadel server
- *
- * Copyright (c) 1987-2021 by the citadel.org team
- *
- * This program is open source software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License, version 3.
- *
- * 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.
- */
-
-#include <errno.h>
-#include <stdio.h>
-#include <syslog.h>
-#include <libcitadel.h>
-#include "modules_init.h"
-#include "serv_extensions.h"
-#include "ctdl_module.h"
-#include "config.h"
-#include "context.h"
-#include "threads.h"
-
-int num_workers = 0; /* Current number of worker threads */
-int active_workers = 0; /* Number of ACTIVE worker threads */
-pthread_key_t ThreadKey;
-pthread_mutex_t Critters[MAX_SEMAPHORES]; /* Things needing locking */
-struct thread_tsd masterTSD;
-int server_shutting_down = 0; /* set to nonzero during shutdown */
-pthread_mutex_t ThreadCountMutex;
-
-void InitializeSemaphores(void)
-{
- int i;
-
- /* Set up a bunch of semaphores to be used for critical sections */
- for (i=0; i<MAX_SEMAPHORES; ++i) {
- pthread_mutex_init(&Critters[i], NULL);
- }
-}
-
-
-/*
- * Obtain a semaphore lock to begin a critical section.
- * but only if no one else has one
- */
-int try_critical_section(int which_one)
-{
- /* For all types of critical sections except those listed here,
- * ensure nobody ever tries to do a critical section within a
- * transaction; this could lead to deadlock.
- */
- if ( (which_one != S_FLOORCACHE)
- && (which_one != S_NETCONFIGS)
- ) {
- cdb_check_handles();
- }
- return (pthread_mutex_trylock(&Critters[which_one]));
-}
-
-
-/*
- * Obtain a semaphore lock to begin a critical section.
- */
-void begin_critical_section(int which_one)
-{
- /* For all types of critical sections except those listed here,
- * ensure nobody ever tries to do a critical section within a
- * transaction; this could lead to deadlock.
- */
- if ( (which_one != S_FLOORCACHE)
- && (which_one != S_NETCONFIGS)
- ) {
- cdb_check_handles();
- }
- pthread_mutex_lock(&Critters[which_one]);
-}
-
-
-/*
- * Release a semaphore lock to end a critical section.
- */
-void end_critical_section(int which_one)
-{
- pthread_mutex_unlock(&Critters[which_one]);
-}
-
-
-/*
- * Return a pointer to our thread-specific (not session-specific) data.
- */
-struct thread_tsd *MyThread(void) {
- struct thread_tsd *c = (struct thread_tsd *) pthread_getspecific(ThreadKey) ;
- if (!c) {
- return &masterTSD;
- }
- return c;
-}
-
-
-/*
- * Called by CtdlThreadCreate()
- * We have to pass through here before starting our thread in order to create a set of data
- * that is thread-specific rather than session-specific.
- */
-void *CTC_backend(void *supplied_start_routine)
-{
- struct thread_tsd *mytsd;
- void *(*start_routine)(void*) = supplied_start_routine;
-
- mytsd = (struct thread_tsd *) malloc(sizeof(struct thread_tsd));
- memset(mytsd, 0, sizeof(struct thread_tsd));
- pthread_setspecific(ThreadKey, (const void *) mytsd);
-
- start_routine(NULL);
- // free(mytsd);
- return(NULL);
-}
-
-
-/*
- * Function to create a thread.
- */
-void CtdlThreadCreate(void *(*start_routine)(void*))
-{
- pthread_t thread;
- pthread_attr_t attr;
- int ret = 0;
-
- ret = pthread_attr_init(&attr);
- ret = pthread_attr_setstacksize(&attr, THREADSTACKSIZE);
- ret = pthread_create(&thread, &attr, CTC_backend, (void *)start_routine);
- if (ret != 0) syslog(LOG_ERR, "pthread_create() : %m");
-}
-
-
-void InitializeMasterTSD(void) {
- memset(&masterTSD, 0, sizeof(struct thread_tsd));
-}
-
-
-/*
- * Initialize the thread system
- */
-void go_threading(void) {
- pthread_mutex_init(&ThreadCountMutex, NULL);
-
- /* Second call to module init functions now that threading is up */
- initialise_modules(1);
-
- /* Begin with one worker thread. We will expand the pool if necessary */
- CtdlThreadCreate(worker_thread);
-
- /* The supervisor thread monitors worker threads and spawns more of them if it finds that
- * they are all in use.
- */
- while (!server_shutting_down) {
- if ((active_workers == num_workers) && (num_workers < CtdlGetConfigInt("c_max_workers"))) {
- CtdlThreadCreate(worker_thread);
- }
- usleep(1000000);
- }
-
- /* When we get to this point we are getting ready to shut down our Citadel server */
- terminate_all_sessions(); /* close all client sockets */
- CtdlShutdownServiceHooks(); /* close all listener sockets to prevent new connections */
- PerformSessionHooks(EVT_SHUTDOWN); /* run any registered shutdown hooks */
-
- /* We used to wait for all threads to exit. Fuck that. The only thing important is that the databases are
- * cleanly unmounted. After that, exit the whole program.
- */
-}
projects / citadel.git / blobdiff