add code for the named semaphores. Configure logic to decide whether to use named or unnamed semaphores still missing.

ompi/mca/sharedfp/sm/sharedfp_sm.h

@@ -9,7 +9,7 @@
  *                         University of Stuttgart.  All rights reserved.
  * Copyright (c) 2004-2005 The Regents of the University of California.
  *                         All rights reserved.
- * Copyright (c) 2008      University of Houston. All rights reserved.
+ * Copyright (c) 2008-2015 University of Houston. All rights reserved.
  * $COPYRIGHT$
  *
  * Additional copyrights may follow
@@ -102,8 +102,8 @@ int mca_sharedfp_sm_iwrite (mca_io_ompio_file_t *fh,
  *--------------------------------------------------------------*/
 
 struct sm_offset{
-    sem_t mutex; /* the mutex: a Posix memory-based semaphore */
-    long long offset; /* and the shared file pointer offset */
+    sem_t *mutex;      /* the mutex: a Posix memory-based unnamed semaphore */
+    long long offset;  /* and the shared file pointer offset */
 };
 
 /*This structure will hang off of the mca_sharedfp_base_data_t's
@@ -114,6 +114,8 @@ struct mca_sharedfp_sm_data
     struct 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 */
+    char *sem_name;    /* Name of the semaphore */
 };
 
 typedef struct mca_sharedfp_sm_data sm_data;

ompi/mca/sharedfp/sm/sharedfp_sm_file_open.c

@@ -9,7 +9,7 @@
  *                         University of Stuttgart.  All rights reserved.
  * Copyright (c) 2004-2005 The Regents of the University of California.
  *                         All rights reserved.
- * Copyright (c) 2013      University of Houston. All rights reserved.
+ * Copyright (c) 2013-2015 University of Houston. All rights reserved.
  * Copyright (c) 2013      Intel, Inc. All rights reserved.
  * $COPYRIGHT$
  *
@@ -156,7 +156,15 @@ int mca_sharedfp_sm_file_open (struct ompi_communicator_t *comm,
 
     /* Initialize semaphore so that is shared between processes.           */
     /* the semaphore is shared by keeping it in the shared memory segment  */
+
+#ifdef OMPIO_SHAREDFP_USE_UNNAMED_SEMAPHORES
     if(sem_init(&sm_offset_ptr->mutex, 1, 1) != -1){
+#else
+    sm_data->sem_name = (char*) malloc( sizeof(char) * (strlen(filename_basename)+32) );
+    sprintf(sm_data->sem_name,"OMPIO_sharedfp_sem_%s",filename_basename);
+
+    if( (sm_data->mutex = sem_open(sm_data->sem_name, O_CREAT, 0644, 1)) != SEM_FAILED ) {
+#endif
 	/*If opening was successful*/
 	/*Store the new file handle*/
 	sm_data->sm_offset_ptr = sm_offset_ptr;
@@ -168,9 +176,16 @@ int mca_sharedfp_sm_file_open (struct ompi_communicator_t *comm,
 	/*write initial zero*/
 	if(rank==0){
 	    MPI_Offset position=0;
-	    sem_wait(&sm_offset_ptr->mutex);
+
+#ifdef OMPIO_SHAREDFP_USE_UNNAMED_SEMAPHORES
+	    sem_wait(sm_offset_ptr->mutex);
 	    sm_offset_ptr->offset=position;
-	    sem_post(&sm_offset_ptr->mutex);
+	    sem_post(sm_offset_ptr->mutex);
+#else
+	    sem_wait(sm_data->mutex);
+	    sm_offset_ptr->offset=position;
+	    sem_post(sm_data->mutex);
+#endif
 	}
     }else{
 	free(sm_data);
@@ -211,7 +226,12 @@ int mca_sharedfp_sm_file_close (mca_io_ompio_file_t *fh)
         /*Close sm handle*/
         if (file_data->sm_offset_ptr) {
             /* destroy semaphore */
-            sem_destroy(&file_data->sm_offset_ptr->mutex);
+#ifdef OMPIO_SHAREDFP_USE_UNNAMED_SEMAPHORES
+	    sem_destroy(file_data->sm_offset_ptr->mutex);
+#else
+ 	    sem_unlink (file_data->sem_name);
+ 	    free (file_data->sem_name);
+#endif
             /*Release the shared memory segment.*/
             munmap(file_data->sm_offset_ptr,sizeof(struct sm_offset));
             /*Q: Do we need to delete the file? */

ompi/mca/sharedfp/sm/sharedfp_sm_request_position.c

@@ -9,7 +9,7 @@
  *                         University of Stuttgart.  All rights reserved.
  * Copyright (c) 2004-2005 The Regents of the University of California.
  *                         All rights reserved.
- * Copyright (c) 2013      University of Houston. All rights reserved.
+ * Copyright (c) 2013-2015 University of Houston. All rights reserved.
  * $COPYRIGHT$
  *
  * Additional copyrights may follow
@@ -47,7 +47,12 @@ int mca_sharedfp_sm_request_position(struct mca_sharedfp_base_data_t * sh,
     sm_offset_ptr = sm_data->sm_offset_ptr;
 
     /* Aquire an exclusive lock */
-    sem_wait(&sm_offset_ptr->mutex);
+
+#ifdef OMPIO_SHAREDFP_USE_UNNAMED_SEMAPHORES
+    sem_wait(sm_offset_ptr->mutex);
+#else
+    sem_wait(sm_data->mutex);
+#endif
 
     if ( mca_sharedfp_sm_verbose ) {
 	printf("Succeeded! Acquired sm lock.for rank=%d\n",rank);
@@ -68,7 +73,12 @@ int mca_sharedfp_sm_request_position(struct mca_sharedfp_base_data_t * sh,
     if ( mca_sharedfp_sm_verbose ) {
 	printf("Releasing sm lock...rank=%d",rank);
     }
-    sem_post(&sm_offset_ptr->mutex);
+
+#ifdef OMPIO_SHAREDFP_USE_UNNAMED_SEMAPHORES
+    sem_post(sm_offset_ptr->mutex);
+#else
+    sem_post(sm_data->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

@@ -9,7 +9,7 @@
  *                         University of Stuttgart.  All rights reserved.
  * Copyright (c) 2004-2005 The Regents of the University of California.
  *                         All rights reserved.
- * Copyright (c) 2013      University of Houston. All rights reserved.
+ * Copyright (c) 2013-2015 University of Houston. All rights reserved.
  * $COPYRIGHT$
  *
  * Additional copyrights may follow
@@ -120,7 +120,12 @@ mca_sharedfp_sm_seek (mca_io_ompio_file_t *fh,
 
         /* Aquire an exclusive lock */
         sm_offset_ptr = sm_data->sm_offset_ptr;
-        sem_wait(&sm_offset_ptr->mutex);
+
+#ifdef OMPIO_SHAREDFP_USE_UNNAMED_SEMAPHORES
+	sem_wait(sm_offset_ptr->mutex);
+#else
+	sem_wait(sm_data->mutex);
+#endif
 
 	if ( mca_sharedfp_sm_verbose ) {
 	    printf("sharedfp_sm_seek: Success! Acquired sm lock.for rank=%d\n",rank);
@@ -129,7 +134,11 @@ 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);
 	}
-        sem_post(&sm_offset_ptr->mutex);
+#ifdef OMPIO_SHAREDFP_USE_UNNAMED_SEMAPHORES
+    sem_post(sm_offset_ptr->mutex);
+#else
+    sem_post(sm_data->mutex);
+#endif
     }
 
     /* since we are only letting process 0, update the current pointer