1 files changed, 81 insertions, 0 deletions
diff --git a/kernel/queue.c b/kernel/queue.c
new file mode 100644
index 0000000..0f2f645
--- /dev/null
+++ b/kernel/queue.c
@@ -0,0 +1,81 @@
+#include <kmalloc.h>
+#include <queue.h>
+#include <sched/scheduler.h>
+#include <stdio.h>
+
+int queue_create(u32 *id) {
+  struct event_queue *q = kcalloc(1, sizeof(struct event_queue));
+  q->wait = 0;
+  list_init(&q->events);
+
+  struct list *list = &current_task->event_queue;
+  list_add(list, q, id);
+  return 1;
+}
+
+struct event_queue *get_event_queue(u32 id) {
+  const struct list *list = &current_task->event_queue;
+  struct event_queue *q;
+  if (!list_get(list, id, (void **)&q)) {
+    return NULL;
+  }
+  return q;
+}
+
+int queue_add(u32 queue_id, struct event *ev, u32 size) {
+  struct event_queue *q = get_event_queue(queue_id);
+  if (!q) {
+    return 0;
+  }
+  for (u32 i = 0; i < size; i++) {
+    // TODO: Should it be a copy or could it be kept in userland to
+    // improve performance?
+    struct event *new_ev = kmalloc(sizeof(struct event));
+    memcpy(new_ev, ev, sizeof(struct event));
+    list_add(&q->events, new_ev, NULL);
+  }
+  return 1;
+}
+
+int queue_should_block(struct event_queue *q, int *is_empty) {
+  if (!q->wait) {
+    return 0;
+  }
+  *is_empty = 1;
+  for (int i = 0;; i++) {
+    struct event *ev;
+    if (!list_get(&q->events, i, (void **)&ev)) {
+      break;
+    }
+    kprintf("wait %d\n", i);
+    *is_empty = 0;
+    if (EVENT_TYPE_FD == ev->type) {
+      kprintf("found fd: %d\n", ev->internal_id);
+      vfs_fd_t *fd = get_vfs_fd(ev->internal_id);
+      kprintf("fd->inode->has_data: %x\n", fd->inode->has_data);
+      if (!fd) {
+        kprintf("queue: Invalid fd given\n");
+        continue;
+      }
+      if (fd->inode->has_data) {
+        kprintf("no block\n");
+        return 0;
+      }
+    } else if (EVENT_TYPE_TCP_SOCKET == ev->type) {
+      kprintf("tcp socket wait\n");
+      return 0;
+    }
+  }
+  return 1;
+}
+
+int queue_wait(u32 queue_id) {
+  struct event_queue *q = get_event_queue(queue_id);
+  if (!q) {
+    return 0;
+  }
+  q->wait = 1;
+  switch_task();
+  q->wait = 0;
+  return 1;
+}