Changeset 16886

Timestamp:

Mar 8, 2008, 11:24:54 AM (18 years ago)

Author:

eugene

Message:

add thread safety to create/delete of buffers

File:

• trunk/Ohana/src/opihi/lib.shell/BufferOps.c (modified) (6 diffs)

trunk/Ohana/src/opihi/lib.shell/BufferOps.c

@@ -4 +4 @@
 static int     Nbuffers;
 
+static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
+
+// this function is NOT thread protected : it is only used in startup and/or shutdown
 void InitBuffers () {
   Nbuffers = 0;
@@ -9 +12 @@
 }
 
+// this function is NOT thread protected : it is only used in startup and/or shutdown
 void FreeBuffers () {
 
@@ -66 +70 @@
   if (i == Nbuffers) { 
     if (mode == OLDBUFFER) goto error;
-    Nbuffers += 1;
+    // lock to protect static array
+    pthread_mutex_lock (&mutex);
+    Nbuffers ++;
     REALLOCATE (buffers, Buffer *, Nbuffers);
     buffers[i] = InitBuffer ();
     strcpy (buffers[i][0].name, name);
+    pthread_mutex_unlock (&mutex);
     return (buffers[i]);
   } 
@@ -154 +161 @@
     return (TRUE);
   }
-
   free (in);
+
+  pthread_mutex_lock (&mutex);
   for (j = i; j < Nbuffers - 1; j++) buffers[j] = buffers[j + 1];
-  Nbuffers -= 1;
+  Nbuffers --;
   REALLOCATE (buffers, Buffer *, MAX (Nbuffers, 1));
+  pthread_mutex_unlock (&mutex);
   return (TRUE);
 }
@@ -175 +184 @@
   free (buffers[i]);
 
+  pthread_mutex_lock (&mutex);
   for (j = i; j < Nbuffers - 1; j++) buffers[j] = buffers[j + 1];
-
-  Nbuffers -= 1;
+  Nbuffers --;
   REALLOCATE (buffers, Buffer *, MAX (Nbuffers, 1));
+  pthread_mutex_unlock (&mutex);
   return (TRUE);
 }
@@ -195 +205 @@
   free (buffers[i]);
 
+  pthread_mutex_lock (&mutex);
   for (j = i; j < Nbuffers - 1; j++) buffers[j] = buffers[j + 1];
-
-  Nbuffers -= 1;
+  Nbuffers --;
   REALLOCATE (buffers, Buffer *, MAX (Nbuffers, 1));
+  pthread_mutex_unlock (&mutex);
   return (TRUE);
 }