73 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			73 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			C
		
	
	
	
| /* Copyright 2002, Red Hat Inc. */
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| 
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| #include <mqueue.h>
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| #include <fcntl.h>
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| #include <errno.h>
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| #include <sys/ipc.h>
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| #include <sys/sem.h>
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| #include <string.h>
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| #include <stdlib.h>
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| #define _LIBC 1
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| #include <sys/lock.h>
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| #undef _LIBC
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| 
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| #include "mqlocal.h"
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| 
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| __LOCK_INIT(static, mq_wrbuf_lock);
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| 
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| int
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| mq_send (mqd_t msgid, const char *msg, size_t msg_len, unsigned int msg_prio)
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| {
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|   struct libc_mq *info;
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|   struct sembuf sb2 = {2, -1, 0};
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|   struct sembuf sb3 = {3, 1, 0};
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|   int rc;
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|   int ipcflag;
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| 
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|   info = __find_mq (msgid);
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| 
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|   if (info == NULL || (info->oflag & O_ACCMODE) == O_RDONLY)
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|     {
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|       errno = EBADF;
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|       return -1;
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|     }
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| 
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|   if (msg_len > info->attr->mq_msgsize)
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|     {
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|       errno = EMSGSIZE;
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|       return -1;
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|     }
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| 
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|   if (msg_prio > MQ_PRIO_MAX)
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|     {
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|       errno = EINVAL;
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|       return -1;
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|     }
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| 
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|   __lock_acquire (mq_wrbuf_lock);
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| 
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|   memcpy (info->wrbuf->text, msg, msg_len);
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|   info->wrbuf->type = (MQ_PRIO_MAX - msg_prio);
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| 
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|   ipcflag = (info->attr->mq_flags & O_NONBLOCK) ? IPC_NOWAIT : 0;
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|   sb2.sem_flg = ipcflag;
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| 
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|   /* check to see if max msgs are on queue */
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|   rc = semop (info->semid, &sb2, 1);
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| 
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|   if (rc == 0)
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|     rc = msgsnd (info->msgqid, info->wrbuf, msg_len, ipcflag);
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| 
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|   if (rc == 0)
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|     semop (info->semid, &sb3, 1);  /* increment number of reads */
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| 
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|   __lock_release (mq_wrbuf_lock);
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|   return rc;
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| }
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|       
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| 
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| 
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| 
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| 
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| 
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