archival commit

1 files changed, 121 insertions, 0 deletions

diff --git a/include/direct.h b/include/direct.h
new file mode 100644
index 0000000..c26907e
--- /dev/null
+++ b/include/direct.h
@@ -0,0 +1,121 @@
+#ifndef DT_H
+#define DT_H
+
+#include <stdbool.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+struct value_t;
+
+typedef struct edge {
+  struct edge *next;
+  struct node *node;
+} edge_t;
+
+typedef struct node {
+  struct edge *edge;
+  value_t x;
+  bool flag;
+  value_t (*function)(struct node *node);
+} node_t;
+
+void dt_connect(node_t *, node_t *);
+void dt_disconnect(node_t *, node_t *);
+void dt_update(node_t *);
+
+value_t dt_one(node_t *node);
+value_t dt_add(node_t *node);
+value_t dt_subtract(node_t *node);
+
+#endif
+
+#ifdef DT_IMPLEMENTATION
+
+void dt_connect(node_t *to, node_t *from) {
+  edge_t *edge = malloc(sizeof(edge_t));
+  edge->node = from;
+  edge->next = to->edge;
+  to->edge = edge;
+}
+
+void dt_disconnect(node_t *to, node_t *from) {
+  edge_t *edge = to->edge;
+  edge_t *last = NULL;
+
+  while (edge) {
+    if (edge->node == from) {
+      edge_t *tmp = edge;
+      last->next = edge->next;
+      free(tmp);
+    }
+
+    last = edge;
+    edge = edge->next;
+  }
+}
+
+void dt_update(node_t *origin) {
+  // printf(">: %p - %lf\n", origin, origin->x);
+
+  edge_t *edge = origin->edge;
+  origin->flag = !origin->flag;
+
+  while (edge) {
+    if (origin->flag != edge->node->flag) {
+      dt_update(edge->node);
+    }
+
+    edge = edge->next;
+  }
+
+  origin->x = origin->function(origin);
+  // printf("<: %p - %lf\n", origin, origin->x);
+}
+
+void dt_update_trace(node_t *origin) {
+  printf(">: %p - %lf\n", origin, origin->x);
+
+  edge_t *edge = origin->edge;
+  origin->flag = !origin->flag;
+
+  while (edge) {
+    if (origin->flag != edge->node->flag) {
+      dt_update_trace(edge->node);
+    }
+
+    edge = edge->next;
+  }
+
+  origin->x = origin->function(origin);
+  printf("<: %p - %lf\n", origin, origin->x);
+}
+
+value_t dt_one(node_t *node) {
+  return 1;
+}
+
+value_t dt_add(node_t *node) {
+  edge_t *edge = node->edge;
+  value_t x = node->x;
+
+  while(edge) {
+    x += edge->node->x;
+    edge = edge->next;
+  }
+
+  return x;
+}
+
+value_t dt_subtract(node_t *node) {
+  edge_t *edge = node->edge;
+  value_t x = node->x;
+
+  while(edge) {
+    x -= edge->node->x;
+    edge = edge->next;
+  }
+
+  return x;
+}
+
+#endif