update

lock_free_queue.h

@@ -1,19 +1,33 @@
+#include <stdint.h>
+#include <stdbool.h>
+
+/*
+ * +--------------+-----------------+----------------+-------------------+-------------+
+ * | unused       | Pop in progress |     Items      | Push in progress  | Unused      |
+ * +--------------+-----------------+----------------+-------------------+-------------+
+ *                ^                 ^                ^                   ^
+ *                temp_head         head             tail                temp_tail
+ */
 
 struct lock_free_queue {
 
-    _Atomic(int) head;
-    _Atomic(int) tail;
-    _Atomic(int) temp;
+    _Atomic(uint64_t) head;
+    _Atomic(uint64_t) tail;
+    _Atomic(uint64_t) temp_head;
+    _Atomic(uint64_t) temp_tail;
 
     // The following aren't written to by
     // push and pop operations, therefore
     // don't need to be atomic.
-    int   size; // Capacity of the queue (item count)
-    int   cell; // Size of a single item (in bytes)
+    uint64_t size; // Capacity of the queue (item count)
+    uint64_t cell; // Size of a single item (in bytes)
     char *base; // Pointer to the first item
 };
+
 void lock_free_queue_init(struct lock_free_queue *q, void *arrptr, int arrlen, int item_size);
 void lock_free_queue_push(struct lock_free_queue *q, void *src);
 void lock_free_queue_pop(struct lock_free_queue *q, void *dst);
+bool lock_free_queue_try_push(struct lock_free_queue *q, void *src);
+bool lock_free_queue_try_pop(struct lock_free_queue *q, void *dst);
 
 #define lock_free_queue_INIT(q, arr) lock_free_queue_init(q, arr, sizeof(arr), sizeof((arr)[0]))