added blueprint for AST library

src/ast/ast.c

@@ -0,0 +1,59 @@
+
+#include <ast/ast.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/log.h>
+
+struct AST_Node_t *AST_new_node(void) {
+  struct AST_Node_t *node = malloc(sizeof(struct AST_Node_t));
+
+  if (node == NULL) {
+    PANIC("failed to allocate AST node");
+  }
+
+  // init to discrete state
+  node->parent = NULL;
+  node->children = NULL;
+  node->child_count = 0;
+
+  return node;
+}
+
+void AST_push_node(struct AST_Node_t *owner, struct AST_Node_t *child) {
+  // if there are no children for now
+  if (owner->child_count == 0) {
+    owner->children = malloc(sizeof(struct AST_Node_t *));
+
+  } else {
+    size_t size = sizeof(struct AST_Node_t *) * (owner->child_count + 1);
+    owner->children = realloc(owner->children, size);
+  }
+
+  if (owner->children == NULL) {
+    PANIC("failed to allocate children array of AST node");
+  }
+
+  owner->children[owner->child_count++] = child;
+}
+
+struct AST_Node_t *AST_get_node(struct AST_Node_t *owner, size_t idx) {
+  if (owner == NULL) {
+    PANIC("AST owner node is NULL");
+  }
+
+  if (owner->children == NULL) {
+    PANIC("AST owner node has no children");
+  }
+
+  struct AST_Node_t *child = owner->children[idx];
+
+  if (child == NULL) {
+    PANIC("child node is NULL");
+  }
+
+  return child;
+}
+
+void AST_delete_node(struct AST_Node_t *_) {
+#warning "FIXME: not implemented"
+}

src/ast/ast.h

@@ -0,0 +1,35 @@
+
+#ifndef _AST_H_
+#define _AST_H_
+
+#include <stdio.h>
+
+struct AST_Node_t {
+  // parent node that owns this node
+  struct AST_Node_t *parent;
+
+  // number of child nodes ownd by this node
+  // length of children array
+  size_t child_count;
+  // variable amount of child nodes
+  struct AST_Node_t **children;
+};
+
+// create a new initialized (empty) node
+struct AST_Node_t *AST_new_node(void);
+
+void AST_delete_node(struct AST_Node_t *);
+
+// add a new child node
+void AST_push_node(struct AST_Node_t *owner, struct AST_Node_t *child);
+
+// get a specific child node
+struct AST_Node_t *AST_get_node(struct AST_Node_t *owner, size_t idx);
+
+// visit this and all of its child nodes calling the given function
+// for every node
+void AST_visit_nodes_recurse(struct AST_Node_t *root,
+                             void (*for_each)(struct AST_Node_t *node,
+                                              size_t depth));
+
+#endif