#include <errno.h>
#include <stdarg.h>
#include <grp.h>
-#ifdef HAVE_PTHREAD_H
-#include <pthread.h>
-#endif
#include <libcitadel.h>
#include "citadel.h"
#include "server.h"
#endif
#include "ctdl_module.h"
+#include "threads.h"
#ifdef DEBUG_MEMORY_LEAKS
struct igheap {
#endif
-pthread_mutex_t Critters[MAX_SEMAPHORES]; /* Things needing locking */
-pthread_key_t MyConKey; /* TSD key for MyContext() */
+citthread_key_t MyConKey; /* TSD key for MyContext() */
int verbosity = DEFAULT_VERBOSITY; /* Logging level */
struct CitContext masterCC;
time_t last_purge = 0; /* Last dead session purge */
-static int num_threads = 0; /* Current number of threads */
-static int num_workers = 0; /* Current number of worker threads */
int num_sessions = 0; /* Current number of sessions */
int syslog_facility = LOG_DAEMON;
static RETSIGTYPE signal_cleanup(int signum) {
CtdlLogPrintf(CTDL_DEBUG, "Caught signal %d; shutting down.\n", signum);
- CtdlThreadStopAll();
- exit_signal = signum;
-}
-
-
-
-
-void InitialiseSemaphores(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);
+#ifdef THREADS_USESIGNALS
+ if (CT)
+ {
+ CtdlLogPrintf(CTDL_DEBUG, "Thread \"%s\" caught signal %d.\n", CT->name, signum);
+ CT->signal = signum;
}
+ else
+#endif
+ exit_signal = signum;
}
* CitContext structure (in the ContextList linked list) of the
* session to which the calling thread is currently bound.
*/
- if (pthread_key_create(&MyConKey, NULL) != 0) {
+ if (citthread_key_create(&MyConKey, NULL) != 0) {
CtdlLogPrintf(CTDL_CRIT, "Can't create TSD key: %s\n",
strerror(errno));
}
* whole Citadel service would come down whenever a single client
* socket breaks.
*/
- //signal(SIGPIPE, SIG_IGN);
- signal(SIGPIPE, signal_cleanup);
+ signal(SIGPIPE, SIG_IGN);
}
-/*
- * Obtain a semaphore lock to begin a critical section.
- */
-void begin_critical_section(int which_one)
-{
- /* CtdlLogPrintf(CTDL_DEBUG, "begin_critical_section(%d)\n", 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)
-#ifdef DEBUG_MEMORY_LEAKS
- && (which_one != S_DEBUGMEMLEAKS)
-#endif
- && (which_one != S_RPLIST)
- ) {
- 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]);
-}
-
/*
register struct CitContext *c;
- return ((c = (struct CitContext *) pthread_getspecific(MyConKey),
+ return ((c = (struct CitContext *) citthread_getspecific(MyConKey),
c == NULL) ? &masterCC : c
);
}
* being set up.
*/
me->state = CON_EXECUTING;
-
/*
* Generate a unique session number and insert this context into
* the list.
}
++num_sessions;
end_critical_section(S_SESSION_TABLE);
- return(me);
+ return (me);
}
* There are no threads so no critical_section stuff is needed.
*/
ptr = ContextList;
+
+ /* We need to update the ContextList because some modules may want to itterate it
+ * Question is should we NULL it before iterating here or should we just keep updating it
+ * as we remove items?
+ *
+ * Answer is to NULL it first to prevent modules from doing any actions on the list at all
+ */
+ ContextList=NULL;
while (ptr != NULL){
/* Remove the session from the active list */
rem = ptr->next;
free (ptr);
ptr = rem;
}
-
}
-/*
- * The system-dependent part of master_cleanup() - close the master socket.
- */
-void sysdep_master_cleanup(void) {
+
+void close_masters (void)
+{
struct ServiceFunctionHook *serviceptr;
/*
serviceptr = serviceptr->next ) {
if (serviceptr->tcp_port > 0)
+ {
CtdlLogPrintf(CTDL_INFO, "Closing listener on port %d\n",
serviceptr->tcp_port);
-
+ serviceptr->tcp_port = 0;
+ }
+
if (serviceptr->sockpath != NULL)
CtdlLogPrintf(CTDL_INFO, "Closing listener on '%s'\n",
serviceptr->sockpath);
close(serviceptr->msock);
-
/* If it's a Unix domain socket, remove the file. */
if (serviceptr->sockpath != NULL) {
unlink(serviceptr->sockpath);
+ serviceptr->sockpath = NULL;
}
}
+}
+
+
+/*
+ * The system-dependent part of master_cleanup() - close the master socket.
+ */
+void sysdep_master_cleanup(void) {
+
+ close_masters();
context_cleanup();
CtdlDestroyFixedOutputHooks();
CtdlDestroySessionHooks();
CtdlDestroyServiceHook();
+ CtdlDestroyRoomHooks();
+ CtdlDestroyDirectoryServiceFuncs();
#ifdef HAVE_BACKTRACE
eCrash_Uninit();
#endif
}
}
-
-
-/*
- * New thread interface.
- * To create a thread you must call one of the create thread functions.
- * You must pass it the address of (a pointer to a CtdlThreadNode initialised to NULL) like this
- * struct CtdlThreadNode *node = NULL;
- * pass in &node
- * If the thread is created *node will point to the thread control structure for the created thread.
- * If the thread creation fails *node remains NULL
- * Do not free the memory pointed to by *node, it doesn't belong to you.
- * If your thread function returns it will be started again without creating a new thread.
- * If your thread function wants to exit it should call CtdlThreadExit(ret_code);
- * This new interface duplicates much of the eCrash stuff. We should go for closer integration since that would
- * remove the need for the calls to eCrashRegisterThread and friends
- */
-
-
-struct CtdlThreadNode *CtdlThreadList = NULL;
-
-/*
- * Condition variable and Mutex for thread garbage collection
- */
-/*static pthread_mutex_t thread_gc_mutex = PTHREAD_MUTEX_INITIALIZER;
-static pthread_cond_t thread_gc_cond = PTHREAD_COND_INITIALIZER;
-*/static pthread_t GC_thread;
-static char *CtdlThreadStates[CTDL_THREAD_LAST_STATE];
-/*
- * Pinched the following bits regarding signals from Kannel.org
- */
-
-/*
- * Change this thread's signal mask to block user-visible signals
- * (HUP, TERM, QUIT, INT), and store the old signal mask in
- * *old_set_storage.
- * Return 0 for success, or -1 if an error occurred.
- */
-
- /*
- * This does not work in Darwin alias MacOS X alias Mach kernel,
- * however. So we define a dummy function doing nothing.
- */
-#if defined(DARWIN_OLD)
- static int pthread_sigmask();
-#endif
-
-static int ctdl_thread_internal_block_signals(sigset_t *old_set_storage)
-{
- int ret;
- sigset_t block_signals;
-
- ret = sigemptyset(&block_signals);
- if (ret != 0) {
- CtdlLogPrintf(CTDL_EMERG, "Thread system PANIC. Couldn't initialize signal set\n");
- return -1;
- }
- ret = sigaddset(&block_signals, SIGHUP);
- ret |= sigaddset(&block_signals, SIGTERM);
- ret |= sigaddset(&block_signals, SIGQUIT);
- ret |= sigaddset(&block_signals, SIGINT);
- if (ret != 0) {
- CtdlLogPrintf(CTDL_EMERG, "Thread system PANIC. Couldn't add signal to signal set.\n");
- return -1;
- }
- ret = pthread_sigmask(SIG_BLOCK, &block_signals, old_set_storage);
- if (ret != 0) {
- CtdlLogPrintf(CTDL_EMERG, "Thread system PANIC. Couldn't disable signals for thread creation\n");
- return -1;
- }
- return 0;
-}
-
-static void ctdl_thread_internal_restore_signals(sigset_t *old_set)
-{
- int ret;
-
- ret = pthread_sigmask(SIG_SETMASK, old_set, NULL);
- if (ret != 0) {
- CtdlLogPrintf(CTDL_EMERG, "Thread system PANIC. Couldn't restore signal set.\n");
- }
-}
-
-
-void ctdl_thread_internal_init(void)
-{
- struct CtdlThreadNode *this_thread;
- int ret = 0;
-
- GC_thread = pthread_self();
- CtdlThreadStates[CTDL_THREAD_INVALID] = strdup ("Invalid Thread");
- CtdlThreadStates[CTDL_THREAD_VALID] = strdup("Valid Thread");
- CtdlThreadStates[CTDL_THREAD_CREATE] = strdup("Thread being Created");
- CtdlThreadStates[CTDL_THREAD_CANCELLED] = strdup("Thread Cancelled");
- CtdlThreadStates[CTDL_THREAD_EXITED] = strdup("Thread Exited");
- CtdlThreadStates[CTDL_THREAD_STOPPING] = strdup("Thread Stopping");
- CtdlThreadStates[CTDL_THREAD_STOP_REQ] = strdup("Thread Stop Requested");
- CtdlThreadStates[CTDL_THREAD_SLEEPING] = strdup("Thread Sleeping");
- CtdlThreadStates[CTDL_THREAD_RUNNING] = strdup("Thread Running");
-
-
- /* Get ourself a thread entry */
- this_thread = malloc(sizeof(struct CtdlThreadNode));
- if (this_thread == NULL) {
- CtdlLogPrintf(CTDL_EMERG, "Thread system, can't allocate CtdlThreadNode, exiting\n");
- return;
- }
- // Ensuring this is zero'd means we make sure the thread doesn't start doing its thing until we are ready.
- memset (this_thread, 0, sizeof(struct CtdlThreadNode));
-
- /* We are garbage collector so create us as running */
- this_thread->state = CTDL_THREAD_RUNNING;
-
- if ((ret = pthread_attr_init(&this_thread->attr))) {
- CtdlLogPrintf(CTDL_EMERG, "Thread system, pthread_attr_init: %s\n", strerror(ret));
- free(this_thread);
- return;
- }
-
- this_thread->name = strdup("Garbage Collection Thread");
-
- pthread_mutex_init (&(this_thread->ThreadMutex), NULL);
- pthread_cond_init (&(this_thread->ThreadCond), NULL);
-
- this_thread->tid = GC_thread;
-
- num_threads++; // Increase the count of threads in the system.
-
- this_thread->next = CtdlThreadList;
- CtdlThreadList = this_thread;
- if (this_thread->next)
- this_thread->next->prev = this_thread;
-}
-
-/*
- * A function to tell all threads to exit
- */
-void CtdlThreadStopAll(void)
-{
- struct CtdlThreadNode *this_thread;
-
- begin_critical_section(S_THREAD_LIST);
- this_thread = CtdlThreadList;
- while(this_thread)
- {
- if (this_thread->thread_func) // Don't tell garbage collector to stop
- {
- pthread_mutex_lock(&this_thread->ThreadMutex); /* To prevent race condition of a sleeping thread */
- if (this_thread->state > CTDL_THREAD_STOP_REQ)
- this_thread->state = CTDL_THREAD_STOP_REQ;
- pthread_mutex_unlock(&this_thread->ThreadMutex);
- pthread_cond_signal(&this_thread->ThreadCond);
- CtdlLogPrintf(CTDL_DEBUG, "Thread system stopping thread \"%s\" (%ld).\n", this_thread->name, this_thread->tid);
- }
- this_thread = this_thread->next;
- }
- end_critical_section(S_THREAD_LIST);
-}
-
-
-/*
- * A function to signal that we need to do garbage collection on the thread list
- */
-void CtdlThreadGC(void)
-{
- struct CtdlThreadNode *this_thread;
-
- CtdlLogPrintf(CTDL_DEBUG, "Thread system signalling garbage collection.\n");
-
- begin_critical_section(S_THREAD_LIST);
- this_thread = CtdlThreadList;
- while(this_thread)
- {
- if (!this_thread->thread_func)
- pthread_cond_signal(&this_thread->ThreadCond);
-
- this_thread = this_thread->next;
- }
- end_critical_section(S_THREAD_LIST);
-}
-
-
-/*
- * A function to return the number of threads running in the system
- */
-int CtdlThreadGetCount(void)
-{
- return num_threads;
-}
-
-/*
- * A function to find the thread structure for this thread
- */
-struct CtdlThreadNode *CtdlThreadSelf(void)
-{
- pthread_t self_tid;
- struct CtdlThreadNode *this_thread;
-
- self_tid = pthread_self();
-
- begin_critical_section(S_THREAD_LIST);
- this_thread = CtdlThreadList;
- while(this_thread)
- {
- if (pthread_equal(self_tid, this_thread->tid))
- {
- end_critical_section(S_THREAD_LIST);
- return this_thread;
- }
- this_thread = this_thread->next;
- }
- end_critical_section(S_THREAD_LIST);
- return NULL;
-}
-
-
-
-
-/*
- * A function to rename a thread
- * Returns a char * and the caller owns the memory and should free it
- */
-char *CtdlThreadName(struct CtdlThreadNode *thread, char *name)
-{
- struct CtdlThreadNode *this_thread;
- char *old_name;
-
- if (!thread)
- this_thread = CtdlThreadSelf();
- else
- this_thread = thread;
- if (!this_thread)
- {
- CtdlLogPrintf(CTDL_WARNING, "Thread system WARNING. Attempt to CtdlThreadRename() a non thread.\n");
- return NULL;
- }
- begin_critical_section(S_THREAD_LIST);
- if (name)
- {
- old_name = this_thread->name;
- this_thread->name = strdup (name);
- free(old_name);
- }
- old_name = strdup(this_thread->name);
- end_critical_section (S_THREAD_LIST);
- return (old_name);
-}
-
-
-/*
- * A function to force a thread to exit
- */
-void CtdlThreadCancel(struct CtdlThreadNode *thread)
-{
- struct CtdlThreadNode *this_thread;
-
- if (!thread)
- this_thread = CtdlThreadSelf();
- else
- this_thread = thread;
- if (!this_thread)
- {
- CtdlLogPrintf(CTDL_EMERG, "Thread system PANIC. Attempt to CtdlThreadCancel() a non thread.\n");
- CtdlThreadStopAll();
- return;
- }
-
- if (!this_thread->thread_func)
- {
- CtdlLogPrintf(CTDL_EMERG, "Thread system PANIC. Attempt to CtdlThreadCancel() the garbage collector.\n");
- CtdlThreadStopAll();
- return;
- }
-
- begin_critical_section(S_THREAD_LIST);
- this_thread->state = CTDL_THREAD_CANCELLED;
- pthread_cancel(this_thread->tid);
- end_critical_section (S_THREAD_LIST);
-}
-
-
-
-/*
- * A function for a thread to check if it has been asked to stop
- */
-int CtdlThreadCheckStop(void)
-{
- struct CtdlThreadNode *this_thread;
-
- this_thread = CtdlThreadSelf();
- if (!this_thread)
- {
- CtdlLogPrintf(CTDL_EMERG, "Thread system PANIC, CtdlThreadCheckStop() called by a non thread.\n");
- CtdlThreadStopAll();
- return -1;
- }
- if(this_thread->state == CTDL_THREAD_STOP_REQ)
- {
- this_thread->state = CTDL_THREAD_STOPPING;
- return -1;
- }
- else if(this_thread->state < CTDL_THREAD_STOP_REQ)
- return -1;
-
- return 0;
-}
-
-
-/*
- * A function to ask a thread to exit
- * The thread must call CtdlThreadCheckStop() periodically to determine if it should exit
- */
-void CtdlThreadStop(struct CtdlThreadNode *thread)
-{
- struct CtdlThreadNode *this_thread;
-
- if (!thread)
- this_thread = CtdlThreadSelf();
- else
- this_thread = thread;
- if (!this_thread)
- return;
- if (!(this_thread->thread_func))
- return; // Don't stop garbage collector
-
- begin_critical_section (S_THREAD_LIST);
- pthread_mutex_lock(&this_thread->ThreadMutex); /* To prevent race condition of a sleeping thread */
- if (this_thread->state > CTDL_THREAD_STOP_REQ)
- this_thread->state = CTDL_THREAD_STOP_REQ;
- pthread_mutex_unlock(&this_thread->ThreadMutex);
- pthread_cond_signal(&this_thread->ThreadCond);
- end_critical_section(S_THREAD_LIST);
-}
-
-/*
- * So we now have a sleep command that works with threads but it is in seconds
- */
-void CtdlThreadSleep(int secs)
-{
- struct timespec wake_time;
- struct timeval time_now;
- struct CtdlThreadNode *self;
- int state;
-
-
- self = CtdlThreadSelf();
- if (!self)
- {
- CtdlLogPrintf(CTDL_WARNING, "CtdlThreadSleep() called by something that is not a thread. Should we die?\n");
- return;
- }
-
- begin_critical_section(S_THREAD_LIST);
- pthread_mutex_lock(&self->ThreadMutex); /* Prevent something asking us to awaken before we've gone to sleep */
- state = self->state;
- if (state == CTDL_THREAD_RUNNING)
- self->state = CTDL_THREAD_SLEEPING;
- end_critical_section(S_THREAD_LIST);
-
- if(state != CTDL_THREAD_RUNNING)
- {
- CtdlLogPrintf(CTDL_DEBUG, "CtdlThreadSleep() called by a thread that is not running.\n");
- pthread_mutex_unlock(&self->ThreadMutex);
- return;
- }
-
- memset (&wake_time, 0, sizeof(struct timespec));
- gettimeofday(&time_now, NULL);
- wake_time.tv_sec = time_now.tv_sec + secs;
- wake_time.tv_nsec = time_now.tv_usec * 10;
- pthread_cond_timedwait(&self->ThreadCond, &self->ThreadMutex, &wake_time);
- begin_critical_section(S_THREAD_LIST);
- if (self->state == CTDL_THREAD_SLEEPING) /* Don't change state if something else changed it while we were asleep */
- self->state = state;
- pthread_mutex_unlock(&self->ThreadMutex);
- end_critical_section(S_THREAD_LIST);
-}
-
-
-/*
- * Routine to clean up our thread function on exit
- */
-static void ctdl_internal_thread_cleanup(void *arg)
-{
- struct CtdlThreadNode *this_thread;
- this_thread = CtdlThreadSelf();
- /*
- * In here we were called by the current thread because it is exiting
- * NB. WE ARE THE CURRENT THREAD
- */
- CtdlLogPrintf(CTDL_NOTICE, "Thread \"%s\" (%ld) exited.\n", this_thread->name, this_thread->tid);
- begin_critical_section(S_THREAD_LIST);
- #ifdef HAVE_BACKTRACE
- eCrash_UnregisterThread();
- #endif
- this_thread->state = CTDL_THREAD_EXITED; // needs to be last thing else house keeping will unlink us too early
- end_critical_section(S_THREAD_LIST);
- CtdlThreadGC();
-}
-
-
-
-
-/*
- * Garbage collection routine.
- * Gets called by main() in a loop to clean up the thread list periodically.
- */
-void ctdl_internal_thread_gc (void)
-{
- struct CtdlThreadNode *this_thread, *that_thread = NULL;
- int workers = 0;
-
- /*
- * Wait on the condition variable that tells us garbage collection is needed
- * We wake up every 10 seconds just in case someone forgot to inform us of a thread exiting
- */
-
- CtdlThreadSleep(10);
-
- /* Handle exiting of garbage collector thread */
- if(num_threads == 1)
- CtdlThreadList->state = CTDL_THREAD_EXITED;
-
- CtdlLogPrintf(CTDL_DEBUG, "Thread system running garbage collection.\n");
- /*
- * Woke up to do garbage collection
- */
- begin_critical_section(S_THREAD_LIST);
- this_thread = CtdlThreadList;
- while(this_thread)
- {
- that_thread = this_thread;
- this_thread = this_thread->next;
-
- CtdlLogPrintf(CTDL_DEBUG, "CtdlThread, \"%s\" (%ld) \"%s\".\n", that_thread->name, that_thread->tid, CtdlThreadStates[that_thread->state]);
- /* Do we need to clean up this thread? */
- if (that_thread->state != CTDL_THREAD_EXITED)
- {
- if(that_thread->flags & CTDLTHREAD_WORKER)
- workers++; /* Sanity check on number of worker threads */
- continue;
- }
-
- if (pthread_equal(that_thread->tid, pthread_self()) && that_thread->thread_func)
- { /* Sanity check */
- end_critical_section(S_THREAD_LIST);
- CtdlLogPrintf(CTDL_EMERG, "Thread system PANIC, a thread is trying to clean up after itself.\n");
- CtdlThreadStopAll();
- return;
- }
-
- if (num_threads <= 0)
- { /* Sanity check */
- end_critical_section (S_THREAD_LIST);
- CtdlLogPrintf(CTDL_EMERG, "Thread system PANIC, num_threads <= 0 and trying to do Garbage Collection.\n");
- CtdlThreadStopAll();
- return;
- }
-
- /* If we are unlinking the list head then the next becomes the list head */
- if (that_thread == CtdlThreadList)
- CtdlThreadList = that_thread->next;
- if(that_thread->prev)
- that_thread->prev->next = that_thread->next;
- if(that_thread->next)
- that_thread->next->prev = that_thread->next;
- num_threads--;
- if(that_thread->flags & CTDLTHREAD_WORKER)
- num_workers--; /* This is a wroker thread so reduce the count. */
-
- /*
- * Join on the thread to do clean up and prevent memory leaks
- * Also makes sure the thread has cleaned up after itself before we remove it from the list
- * If that thread has no function it must be the garbage collector
- */
- if (that_thread->thread_func)
- pthread_join (that_thread->tid, NULL);
-
- /*
- * Now we own that thread entry
- */
- CtdlLogPrintf(CTDL_INFO, "Garbage Collection for thread \"%s\" (%ld).\n", that_thread->name, that_thread->tid);
- if(that_thread->name)
- free(that_thread->name);
- pthread_mutex_destroy(&that_thread->ThreadMutex);
- pthread_cond_destroy(&that_thread->ThreadCond);
- pthread_attr_destroy(&that_thread->attr);
- free(that_thread);
- that_thread = NULL;
- }
-
- /* Sanity check number of worker threads */
- if (workers != num_workers)
- {
- end_critical_section(S_THREAD_LIST);
- CtdlLogPrintf(CTDL_EMERG, "Thread system PANIC, discrepancy in number of worker threads. Counted %d, should be %d.\n", workers, num_workers);
- return;
- }
-
- end_critical_section(S_THREAD_LIST);
-}
-
-
-
-
-/*
- * Runtime function for a Citadel Thread.
- * This initialises the threads environment and then calls the user supplied thread function
- * Note that this is the REAL thread function and wraps the users thread function.
- */
-static void *ctdl_internal_thread_func (void *arg)
-{
- struct CtdlThreadNode *this_thread;
- void *ret = NULL;
-
- /* lock and unlock the thread list.
- * This causes this thread to wait until all its creation stuff has finished before it
- * can continue its execution.
- */
- begin_critical_section(S_THREAD_LIST);
- // Get our thread data structure
- this_thread = (struct CtdlThreadNode *) arg;
- this_thread->state = CTDL_THREAD_RUNNING;
- this_thread->pid = getpid();
- end_critical_section(S_THREAD_LIST);
-
- // Tell the world we are here
- CtdlLogPrintf(CTDL_NOTICE, "Created a new thread \"%s\" (%ld). \n", this_thread->name, this_thread->tid);
-
- // Register the cleanup function to take care of when we exit.
- pthread_cleanup_push(ctdl_internal_thread_cleanup, NULL);
-
-
- /*
- * run the thread to do the work
- */
- ret = (this_thread->thread_func)(this_thread->user_args);
-
- /*
- * Our thread is exiting either because it wanted to end or because the server is stopping
- * We need to clean up
- */
- pthread_cleanup_pop(1); // Execute our cleanup routine and remove it
-
- return(ret);
-}
-
-
-
-/*
- * Internal function to create a thread.
- * Must be called from within a S_THREAD_LIST critical section
- */
-struct CtdlThreadNode *ctdl_internal_create_thread(char *name, long flags, void *(*thread_func) (void *arg), void *args)
-{
- int ret = 0;
- struct CtdlThreadNode *this_thread;
- int sigtrick = 0;
- sigset_t old_signal_set;
-
- if (num_threads >= 32767)
- {
- CtdlLogPrintf(CTDL_EMERG, "Thread system. Thread list full.\n");
- return NULL;
- }
-
- this_thread = malloc(sizeof(struct CtdlThreadNode));
- if (this_thread == NULL) {
- CtdlLogPrintf(CTDL_EMERG, "Thread system, can't allocate CtdlThreadNode, exiting\n");
- return NULL;
- }
- // Ensuring this is zero'd means we make sure the thread doesn't start doing its thing until we are ready.
- memset (this_thread, 0, sizeof(struct CtdlThreadNode));
-
- this_thread->state = CTDL_THREAD_CREATE;
-
- if ((ret = pthread_attr_init(&this_thread->attr))) {
- CtdlLogPrintf(CTDL_EMERG, "Thread system, pthread_attr_init: %s\n", strerror(ret));
- free(this_thread);
- return NULL;
- }
-
- /* Our per-thread stacks need to be bigger than the default size,
- * otherwise the MIME parser crashes on FreeBSD, and the IMAP service
- * crashes on 64-bit Linux.
- */
- if (flags & CTDLTHREAD_BIGSTACK)
- {
- CtdlLogPrintf(CTDL_INFO, "Thread system. Creating BIG STACK thread.\n");
- if ((ret = pthread_attr_setstacksize(&this_thread->attr, THREADSTACKSIZE))) {
- CtdlLogPrintf(CTDL_EMERG, "Thread system, pthread_attr_setstacksize: %s\n",
- strerror(ret));
- pthread_attr_destroy(&this_thread->attr);
- free(this_thread);
- return NULL;
- }
- }
-
- /*
- * If we got here we are going to create the thread so we must initilise the structure
- * first because most implimentations of threading can't create it in a stopped state
- * and it might want to do things with its structure that aren't initialised otherwise.
- */
- if(name)
- {
- this_thread->name = strdup(name);
- }
- else
- {
- this_thread->name = strdup("Un-named Thread");
- }
-
- this_thread->flags = flags;
- this_thread->thread_func = thread_func;
- this_thread->user_args = args;
- pthread_mutex_init (&(this_thread->ThreadMutex), NULL);
- pthread_cond_init (&(this_thread->ThreadCond), NULL);
-
- /*
- * We want to make sure that only the main thread handles signals,
- * so that each signal is handled exactly once. To do this, we
- * make sure that each new thread has all the signals that we
- * handle blocked. To avoid race conditions, we block them in
- * the spawning thread first, then create the new thread (which
- * inherits the settings), and then restore the old settings in
- * the spawning thread. This means that there is a brief period
- * when no signals will be processed, but during that time they
- * should be queued by the operating system.
- */
- if (pthread_equal(GC_thread, pthread_self()))
- sigtrick = ctdl_thread_internal_block_signals(&old_signal_set) == 0;
-
- /*
- * We pass this_thread into the thread as its args so that it can find out information
- * about itself and it has a bit of storage space for itself, not to mention that the REAL
- * thread function needs to finish off the setup of the structure
- */
- if ((ret = pthread_create(&this_thread->tid, &this_thread->attr, ctdl_internal_thread_func, this_thread) != 0))
- {
-
- CtdlLogPrintf(CTDL_ALERT, "Thread system, Can't create thread: %s\n",
- strerror(ret));
- if (this_thread->name)
- free (this_thread->name);
- pthread_mutex_destroy(&(this_thread->ThreadMutex));
- pthread_cond_destroy(&(this_thread->ThreadCond));
- pthread_attr_destroy(&this_thread->attr);
- free(this_thread);
- if (sigtrick)
- ctdl_thread_internal_restore_signals(&old_signal_set);
- return NULL;
- }
-
- if (sigtrick)
- ctdl_thread_internal_restore_signals(&old_signal_set);
-
- num_threads++; // Increase the count of threads in the system.
- if(this_thread->flags & CTDLTHREAD_WORKER)
- num_workers++;
-
- this_thread->next = CtdlThreadList;
- CtdlThreadList = this_thread;
- if (this_thread->next)
- this_thread->next->prev = this_thread;
- // Register for tracing
- #ifdef HAVE_BACKTRACE
- eCrash_RegisterThread(this_thread->name, 0);
- #endif
- return this_thread;
-}
-
-/*
- * Wrapper function to create a thread
- * ensures the critical section and other protections are in place.
- * char *name = name to give to thread, if NULL, use generic name
- * int flags = flags to determine type of thread and standard facilities
- */
-struct CtdlThreadNode *CtdlThreadCreate(char *name, long flags, void *(*thread_func) (void *arg), void *args)
-{
- struct CtdlThreadNode *ret = NULL;
-
- begin_critical_section(S_THREAD_LIST);
- ret = ctdl_internal_create_thread(name, flags, thread_func, args);
- end_critical_section(S_THREAD_LIST);
- return ret;
-}
-
-
-
-
/*
* Purge all sessions which have the 'kill_me' flag set.
* This function has code to prevent it from running more than once every
* few seconds, because running it after every single unbind would waste a lot
* of CPU time and keep the context list locked too much. To force it to run
* anyway, set "force" to nonzero.
- *
- *
- * After that's done, we raise the size of the worker thread pool
- * if such an action is appropriate.
*/
void dead_session_purge(int force) {
struct CitContext *ptr, *ptr2; /* general-purpose utility pointer */
struct CitContext *rem = NULL; /* list of sessions to be destroyed */
-
+
if (force == 0) {
if ( (time(NULL) - last_purge) < 5 ) {
return; /* Too soon, go away */
}
time(&last_purge);
- begin_critical_section(S_SESSION_TABLE);
+ if (try_critical_section(S_SESSION_TABLE))
+ return;
+
ptr = ContextList;
while (ptr) {
ptr2 = ptr;
}
--num_sessions;
-
/* And put it on our to-be-destroyed list */
ptr2->next = rem;
rem = ptr2;
-
}
}
end_critical_section(S_SESSION_TABLE);
rem = rem->next;
free(ptr);
}
-
- /* Raise the size of the worker thread pool if necessary. */
- begin_critical_section(S_THREAD_LIST);
- if ( (num_sessions > num_workers)
- && (num_workers < config.c_max_workers) ) {
- ctdl_internal_create_thread(NULL, CTDLTHREAD_BIGSTACK + CTDLTHREAD_WORKER, worker_thread, NULL);
- }
- end_critical_section(S_THREAD_LIST);
- // FIXME: reduce the number of worker threads too
}
* Bind a thread to a context. (It's inline merely to speed things up.)
*/
INLINE void become_session(struct CitContext *which_con) {
- pthread_setspecific(MyConKey, (void *)which_con );
+ citthread_setspecific(MyConKey, (void *)which_con );
}
/*
* This loop just keeps going and going and going...
- */
+ */
+/*
+ * FIXME:
+ * This current implimentation of worker_thread creates a bottle neck in several situations
+ * The first thing to remember is that a single thread can handle more than one connection at a time.
+ * More threads mean less memory for the system to run in.
+ * So for efficiency we want every thread to be doing something useful or waiting in the main loop for
+ * something to happen anywhere.
+ * This current implimentation requires worker threads to wait in other locations, after it has
+ * been committed to a single connection which is very wasteful.
+ * As an extreme case consider this:
+ * A slow client connects and this slow client sends only one character each second.
+ * With this current implimentation a single worker thread is dispatched to handle that connection
+ * until such times as the client timeout expires, an error occurs on the socket or the client
+ * completes its transmission.
+ * THIS IS VERY BAD since that thread could have handled a read from many more clients in each one
+ * second interval between chars.
+ *
+ * It is my intention to re-write this code and the associated client_getln, client_read functions
+ * to allow any thread to read data on behalf of any connection (context).
+ * To do this I intend to have this main loop read chars into a buffer stored in the context.
+ * Once the correct criteria for a full buffer is met then we will dispatch a thread to
+ * process it.
+ * This worker thread loop also needs to be able to handle binary data.
+ */
+
void *worker_thread(void *arg) {
int i;
int highest;
struct timeval tv;
int force_purge = 0;
int m;
-
- cdb_allocate_tsd();
+
while (!CtdlThreadCheckStop()) {
if (!CtdlThreadCheckStop()) {
tv.tv_sec = 1; /* wake up every second if no input */
tv.tv_usec = 0;
- retval = select(highest + 1, &readfds, NULL, NULL, &tv);
+ retval = CtdlThreadSelect(highest + 1, &readfds, NULL, NULL, &tv);
}
if (CtdlThreadCheckStop()) return(NULL);
dead_session_purge(force_purge);
do_housekeeping();
- check_sched_shutdown();
}
/* If control reaches this point, the server is shutting down */
return(NULL);