repo init. partial port of existing code

1 files changed, 66 insertions, 0 deletions

diff --git a/src/std/containers/ring_queue.c b/src/std/containers/ring_queue.c
new file mode 100644
index 0000000..a9d3506
--- /dev/null
+++ b/src/std/containers/ring_queue.c
@@ -0,0 +1,66 @@
+#include "ring_queue.h"
+#include <stdlib.h>
+#include "defines.h"
+
+ring_queue* ring_queue_new(size_t type_size, size_t capacity, void* memory) {
+  ring_queue* q = malloc(sizeof(ring_queue));
+  q->len = 0;
+  q->capacity = capacity;
+  q->type_size = type_size;
+  q->head = 0;
+  q->tail = -1;
+
+  if (memory) {
+    // caller owns the memory
+    q->owns_memory = false;
+    q->data = memory;
+  } else {
+    // ring queue should own the memory
+    q->owns_memory = true;
+    q->data = malloc(capacity * type_size);
+  }
+
+  return q;
+}
+
+void ring_queue_free(ring_queue* queue) {
+  if (queue) {
+    if (queue->owns_memory) {
+      free(queue->data);
+    }
+    free(queue);
+  }
+}
+
+bool ring_queue_enqueue(ring_queue* queue, const void* value) {
+  if (queue->len == queue->capacity) {
+    return false;
+  }
+
+  queue->tail = (queue->tail + 1) % queue->capacity;
+  memcpy(queue->data + (queue->tail * queue->type_size), value, queue->type_size);
+  queue->len++;
+  return true;
+}
+
+bool ring_queue_dequeue(ring_queue* queue, void* out_value) {
+  if (queue->len == 0) {
+    // queue is empty
+    return false;
+  }
+
+  memcpy(out_value, queue->data + (queue->head * queue->type_size), queue->type_size);
+  queue->head = (queue->head + 1) % queue->capacity;
+  queue->len--;
+  return true;
+}
+
+bool ring_queue_peek(const ring_queue* queue, void* out_value) {
+  if (queue->len == 0) {
+    // queue is empty
+    return false;
+  }
+
+  memcpy(out_value, queue->data + (queue->head * queue->type_size), queue->type_size);
+  return true;
+}
\ No newline at end of file