NdbCondition.c
上传用户:romrleung
上传日期:2022-05-23
资源大小:18897k
文件大小:6k
- /* Copyright (C) 2003 MySQL 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 */
- #include "NdbCondition.h"
- #include <pthread.h>
- #include <sys/types.h>
- #include <malloc.h>
- #include <NdbMutex.h>
- #include "NdbConditionOSE.h"
- struct NdbCondition
- {
- PROCESS condserv_pid;
- };
- OS_PROCESS(ndbcond_serv){
- union SIGNAL* sig;
- union SIGNAL* sig2;
- static const SIGSELECT sel_signal[] = {2, NDBCOND_SIGNAL, NDBCOND_BROADCAST};
- static const SIGSELECT sel_cond[] = {2, NDBCOND_WAIT, NDBCOND_WAITTIMEOUT};
- for(;;){
- /* Receive condition wait signal */
- sig = receive((SIGSELECT*)sel_cond);
- if (sig != NIL){
- switch (sig->sigNo){
- case NDBCOND_WAIT:
- /* Wait for a SIGNAL or BROADCAST from anyone */
- sig2 = receive((SIGSELECT*)sel_signal);
- if (sig2 != NIL){
- switch(sig2->sigNo){
- case NDBCOND_SIGNAL:
- ((struct NdbCondWait*)sig)->status = NDBCOND_SIGNALED;
- /* Send signal back to the one waiting for this condition */
- send(&sig, sender(&sig));
- break;
- case NDBCOND_BROADCAST:
- /* Not handled yet */
- assert(1==0);
- break;
- default:
- assert(1==0);
- break;
- }
- free_buf(&sig2);
- }
- break;
- case NDBCOND_WAITTIMEOUT:
- /* Wait for a SIGNAL or BROADCAST from anyone */
- sig2 = receive_w_tmo(((struct NdbCondWaitTimeout*)sig)->timeout, (SIGSELECT*)sel_signal);
- if (sig2 != NIL){
- switch(sig2->sigNo){
- case NDBCOND_SIGNAL:
- ((struct NdbCondWaitTimeout*)sig)->status = NDBCOND_SIGNALED;
- /* Send signal back to the one waiting for this condition */
- send(&sig, sender(&sig));
- break;
- case NDBCOND_BROADCAST:
- /* Not handled yet */
- assert(1==0);
- break;
- default:
- assert(1==0);
- break;
- }
- free_buf(&sig2);
- }else{
- ((struct NdbCondWaitTimeout*)sig)->status = NDBCOND_TIMEOUT;
- send(&sig, sender(&sig));
- }
- break;
- default:
- assert(1==0);
- break;
-
- }
- }
- }
- }
- struct NdbCondition*
- NdbCondition_Create(void)
- {
- struct NdbCondition* tmpCond;
-
-
- tmpCond = (struct NdbCondition*)malloc(sizeof(struct NdbCondition));
-
- if (tmpCond == NULL)
- return NULL;
- /**
- * Start this process with a quite high
- * priority, we want it to be responsive
- */
- tmpCond->condserv_pid = create_process(OS_PRI_PROC, /* Process type */
- "ndbcond_serv", /* Name */
- ndbcond_serv, /* Entry point */
- 2048, /* Stack size */
- 10, /* Priority */
- 0, /* Time slice */
- get_bid(current_process()), /* Block */
- NULL, /* Redir table */
- 0,
- 0);
-
- start(tmpCond->condserv_pid);
- return tmpCond;
- }
- int
- NdbCondition_Wait(struct NdbCondition* p_cond,
- NdbMutex* p_mutex)
- {
- static const SIGSELECT sel_cond[] = {1, NDBCOND_WAIT};
- union SIGNAL* sig;
- int result;
- if (p_cond == NULL || p_mutex == NULL)
- return 0;
-
- sig = alloc(sizeof(struct NdbCondWait), NDBCOND_WAIT);
- send(&sig, p_cond->condserv_pid);
- NdbMutex_Unlock(p_mutex);
-
- result = 1;
- while(NIL == (sig = receive_from((OSTIME)-1, (SIGSELECT*)sel_cond, p_cond->condserv_pid)));
- if (sig != NIL){
- if (sig->sigNo == NDBCOND_WAIT){
- /* Condition is signaled */
- result = 0;
- }else{
- assert(1==0);
- }
- free_buf(&sig);
-
- }
- NdbMutex_Lock(p_mutex);
- return result;
- }
- int
- NdbCondition_WaitTimeout(struct NdbCondition* p_cond,
- NdbMutex* p_mutex,
- int msecs){
- static const SIGSELECT sel_cond[] = {1, NDBCOND_WAITTIMEOUT};
- union SIGNAL* sig;
- int result;
- if (p_cond == NULL || p_mutex == NULL)
- return 0;
-
- sig = alloc(sizeof(struct NdbCondWaitTimeout), NDBCOND_WAITTIMEOUT);
- ((struct NdbCondWaitTimeout*)sig)->timeout = msecs;
- send(&sig, p_cond->condserv_pid);
- NdbMutex_Unlock(p_mutex);
-
- result = 1;
- while(NIL == (sig = receive_from((OSTIME)-1, (SIGSELECT*)sel_cond, p_cond->condserv_pid)));
- if (sig != NIL){
- if (sig->sigNo == NDBCOND_WAITTIMEOUT){
- /* Condition is signaled */
- result = 0;
- }else{
- assert(1==0);
- }
- free_buf(&sig);
-
- }
-
- NdbMutex_Lock(p_mutex);
-
- return result;
- }
- int
- NdbCondition_Signal(struct NdbCondition* p_cond){
- union SIGNAL* sig;
- if (p_cond == NULL)
- return 1;
- sig = alloc(sizeof(struct NdbCondSignal), NDBCOND_SIGNAL);
- send(&sig, p_cond->condserv_pid);
-
- return 0;
- }
- int NdbCondition_Broadcast(struct NdbCondition* p_cond)
- {
- union SIGNAL* sig;
- if (p_cond == NULL)
- return 1;
- sig = alloc(sizeof(struct NdbCondBroadcast), NDBCOND_BROADCAST);
- send(&sig, p_cond->condserv_pid);
-
- return 0;
- }
- int NdbCondition_Destroy(struct NdbCondition* p_cond)
- {
- if (p_cond == NULL)
- return 1;
- kill_proc(p_cond->condserv_pid);
- free(p_cond);
- return 0;
- }