sharedfp: have sm_data->mutex always point to the right mutex

Even if the mutex is actually located in
sm_data->sm_offset_ptr->mutex, have sm_data->mutex point to it.  This
avoids a few #if blocks that are otherwise identical.

Author: jsquyres

ompi/mca/sharedfp/sm/sharedfp_sm.h

@@ -101,7 +101,7 @@ int mca_sharedfp_sm_iwrite (mca_io_ompio_file_t *fh,
  *Structures and definitions only for this component
  *--------------------------------------------------------------*/
 struct mca_sharedfp_sm_offset{
-    sem_t mutex;      /* the mutex: a Posix memory-based unnamed semaphore */
+    sem_t mutex;      /* the mutex: a POSIX memory-based unnamed semaphore */
     long long offset;  /* and the shared file pointer offset */
 };
 
@@ -113,7 +113,10 @@ struct mca_sharedfp_sm_data
     struct mca_sharedfp_sm_offset * sm_offset_ptr;
     /*save filename so that we can remove the file on close*/
     char * sm_filename;
-    sem_t *mutex;      /* the mutex: a Posix memory-based named semaphore */
+    /* The mutex: it will either point to a POSIX memory-based named
+       semaphore, or it will point to the a POSIX memory-based unnamed
+       semaphore located in sm_offset_ptr->mutex. */
+    sem_t *mutex;
     char *sem_name;    /* Name of the semaphore */
 };
 

ompi/mca/sharedfp/sm/sharedfp_sm_file_open.c

@@ -170,6 +170,7 @@ int mca_sharedfp_sm_file_open (struct ompi_communicator_t *comm,
 
     if( (sm_data->mutex = sem_open(sm_data->sem_name, O_CREAT, 0644, 1)) != SEM_FAILED ) {
 #elif defined(HAVE_SEM_INIT)
+    sm_data->mutex = &sm_offset_ptr->mutex;
     if(sem_init(&sm_offset_ptr->mutex, 1, 1) != -1){
 #endif
 	/*If opening was successful*/
@@ -184,15 +185,9 @@ int mca_sharedfp_sm_file_open (struct ompi_communicator_t *comm,
 	if(rank==0){
 	    MPI_Offset position=0;
 
-#if defined(HAVE_SEM_OPEN)
 	    sem_wait(sm_data->mutex);
 	    sm_offset_ptr->offset=position;
 	    sem_post(sm_data->mutex);
-#elif defined(HAVE_SEM_INIT)
-	    sem_wait(&sm_offset_ptr->mutex);
-	    sm_offset_ptr->offset=position;
-	    sem_post(&sm_offset_ptr->mutex);
-#endif
 	}
     }else{
         free(sm_filename);

ompi/mca/sharedfp/sm/sharedfp_sm_request_position.c

@@ -48,11 +48,7 @@ int mca_sharedfp_sm_request_position(struct mca_sharedfp_base_data_t * sh,
 
     /* Aquire an exclusive lock */
 
-#if defined(HAVE_SEM_OPEN)
     sem_wait(sm_data->mutex);
-#elif defined(HAVE_SEM_INIT)
-    sem_wait(&sm_offset_ptr->mutex);
-#endif
 
     if ( mca_sharedfp_sm_verbose ) {
 	printf("Succeeded! Acquired sm lock.for rank=%d\n",rank);
@@ -74,11 +70,7 @@ int mca_sharedfp_sm_request_position(struct mca_sharedfp_base_data_t * sh,
 	printf("Releasing sm lock...rank=%d",rank);
     }
 
-#if defined(HAVE_SEM_OPEN)
     sem_post(sm_data->mutex);
-#elif defined(HAVE_SEM_INIT)
-    sem_post(&sm_offset_ptr->mutex);
-#endif
     if ( mca_sharedfp_sm_verbose ) {
 	printf("Released lock! released lock.for rank=%d\n",rank);
     }

ompi/mca/sharedfp/sm/sharedfp_sm_seek.c

@@ -121,11 +121,7 @@ mca_sharedfp_sm_seek (mca_io_ompio_file_t *fh,
         /* Aquire an exclusive lock */
         sm_offset_ptr = sm_data->sm_offset_ptr;
 
-#if defined(HAVE_SEM_OPEN)
 	sem_wait(sm_data->mutex);
-#elif defined(HAVE_SEM_INIT)
-	sem_wait(&sm_offset_ptr->mutex);
-#endif
 
 	if ( mca_sharedfp_sm_verbose ) {
 	    printf("sharedfp_sm_seek: Success! Acquired sm lock.for rank=%d\n",rank);
@@ -134,11 +130,7 @@ mca_sharedfp_sm_seek (mca_io_ompio_file_t *fh,
 	if ( mca_sharedfp_sm_verbose ) {
 	    printf("sharedfp_sm_seek: Releasing sm lock...rank=%d",rank); fflush(stdout);
 	}
-#if defined(HAVE_SEM_OPEN)
-    sem_post(sm_data->mutex);
-#elif defined(HAVE_SEM_INIT)
-    sem_post(&sm_offset_ptr->mutex);
-#endif
+        sem_post(sm_data->mutex);
     }
 
     /* since we are only letting process 0, update the current pointer