function 'request' for handling readN serverside

lib/threadpool/fileQueue.c

@@ -198,7 +198,6 @@ _end_dequeue:
     return NULL;
 }
 
-
 /* dequeue until we have s free space and expand the file by s */
 fileT ** dequeueN(queueT *q, char *filepath, size_t s) {
     if(!q) {
@@ -211,6 +210,8 @@ fileT ** dequeueN(queueT *q, char *filepath, size_t s) {
 
     LOCK_RETURN(&q->m, NULL); /* begin me */
 
+    fileT **returnList = NULL; /* list of removed files */
+
     if (q->head == NULL || q->len == 0) { /* empty queue */
 	errno = ENOENT;
 	goto _end_dequeueN;
@@ -235,10 +236,13 @@ fileT ** dequeueN(queueT *q, char *filepath, size_t s) {
 	goto _end_dequeueN;
     }
 
-    fileT **returnList = NULL; /* list of removed files */
     tmp = NULL;
 
-    returnList = calloc(1, sizeof(fileT*));
+    returnList = calloc(1, sizeof(*returnList));
+    if(!returnList) {
+	perror("dequeueN: calloc");
+	goto _end_dequeueN;
+    }
     returnList[0] = NULL;
 
     int purged = 0;
@@ -272,6 +276,8 @@ fileT ** dequeueN(queueT *q, char *filepath, size_t s) {
 
 _end_dequeueN:
     UNLOCK_RETURN(&q->m, NULL);
+    if(returnList)
+	free(returnList);
     return NULL;
 }
 
@@ -765,6 +771,57 @@ _end_find_in_queue:
     return NULL;
 }
 
+/* return n files */
+fileT ** request(queueT *q, int n) {
+    if(!q) {
+	errno = EINVAL;
+	return NULL;
+    }
+    if(n<=0) {
+	return NULL;
+    }
+
+    LOCK_RETURN(&q->m, NULL); /* begin me */
+
+    fileT **returnList = NULL; /* list of requested files */
+
+    if (q->head == NULL || q->len == 0) { /* empty queue */
+	errno = ENOENT;
+	goto _end_request;
+    }
+
+    if(q->size < n) {
+	errno = EINVAL;
+	goto _end_request;
+    }
+
+    returnList = calloc(n+1, sizeof(*returnList));
+    if(!returnList) {
+	perror("dequeueN: calloc");
+	goto _end_request;
+    }
+    returnList[n] = NULL;
+
+    nodeT *tmp = q->head;
+    for(int i=0; i<n; ++i) {
+	if(tmp == NULL) {
+	    errno = ENOENT;
+	    goto _end_request;
+	}
+	returnList[i] = tmp->data;
+	tmp = tmp->next;
+    }
+
+    UNLOCK_RETURN(&q->m, NULL); /* end me */
+    return returnList;
+
+_end_request:
+    UNLOCK_RETURN(&q->m, NULL);
+    if(returnList)
+	free(returnList);
+    return NULL;
+}
+
 /* search for file and return result of search */
 int searchFile(queueT *q, char *filepath) {
     if(!q || !filepath) {