Add code generation for doubly linked list

codegen/dbl_list/snippets/list_empty

@@ -0,0 +1,8 @@
+  if (!list) {{
+    return;
+  }}
+
+  u64 count = list->node_count;
+  for (u64 i = 0; i < count; ++i) {{
+    wapp_str8_list_pop_back(list);
+  }}

codegen/dbl_list/snippets/list_get

@@ -0,0 +1,13 @@
+  if (index >= list->node_count) {{
+    return NULL;
+  }}
+
+  {T}Node *output  = NULL;
+  {T}Node *current = list->first;
+  for (u64 i = 1; i <= index; ++i) {{
+    current = current->next;
+  }}
+
+  output = current;
+
+  return output;

codegen/dbl_list/snippets/list_insert

@@ -0,0 +1,29 @@
+  if (!list || !node || !(node->string)) {{
+    return;
+  }}
+
+  if (index == 0) {{
+    wapp_str8_list_push_front(list, node);
+    return;
+  }} else if (index == list->node_count) {{
+    wapp_str8_list_push_back(list, node);
+    return;
+  }}
+
+  {T}Node *dst_node = wapp_str8_list_get(list, index);
+  if (!dst_node) {{
+    return;
+  }}
+
+  {T}List node_list = {Tlower}_node_to_list(node);
+
+  list->total_size += node_list.total_size;
+  list->node_count += node_list.node_count;
+
+  {T}Node *prev = dst_node->prev;
+
+  dst_node->prev = node_list.last;
+  prev->next     = node_list.first;
+
+  node_list.first->prev = prev;
+  node_list.last->next  = dst_node;

codegen/dbl_list/snippets/list_pop_back

@@ -0,0 +1,21 @@
+  {T}Node *output = NULL;
+
+  if (!list || list->node_count == 0) {{
+    goto RETURN_{Tupper}_LIST_POP_BACK;
+  }}
+
+  output = list->last;
+
+  if (list->node_count == 1) {{
+    *list = ({T}List){{0}};
+    goto RETURN_{Tupper}_LIST_POP_BACK;
+  }}
+
+  --(list->node_count);
+  list->total_size -= output->string->size;
+  list->last        = output->prev;
+
+  output->prev = output->next = NULL;
+
+RETURN_{Tupper}_LIST_POP_BACK:
+  return output;

codegen/dbl_list/snippets/list_pop_front

@@ -0,0 +1,21 @@
+  {T}Node *output = NULL;
+
+  if (!list || list->node_count == 0) {{
+    goto RETURN_{Tupper}_LIST_POP_FRONT;
+  }}
+
+  output = list->first;
+
+  if (list->node_count == 1) {{
+    *list = ({T}List){{0}};
+    goto RETURN_{Tupper}_LIST_POP_FRONT;
+  }}
+
+  --(list->node_count);
+  list->total_size -= output->string->size;
+  list->first       = output->next;
+
+  output->prev = output->next = NULL;
+
+RETURN_{Tupper}_LIST_POP_FRONT:
+  return output;

codegen/dbl_list/snippets/list_push_back

@@ -0,0 +1,21 @@
+  if (!list || !node || !(node->string)) {{
+    return;
+  }}
+
+  {T}List node_list = {Tlower}_node_to_list(node);
+
+  if (list->node_count == 0) {{
+    *list = node_list;
+    return;
+  }}
+
+  list->total_size += node_list.total_size;
+  list->node_count += node_list.node_count;
+
+  {T}Node *last = list->last;
+  if (last) {{
+    last->next = node_list.first;
+  }}
+
+  list->last            = node_list.last;
+  node_list.first->prev = last;

codegen/dbl_list/snippets/list_push_front

@@ -0,0 +1,21 @@
+  if (!list || !node || !(node->string)) {{
+    return;
+  }}
+
+  {T}List node_list = {Tlower}_node_to_list(node);
+
+  if (list->node_count == 0) {{
+    *list = node_list;
+    return;
+  }}
+
+  list->total_size += node_list.total_size;
+  list->node_count += node_list.node_count;
+
+  {T}Node *first = list->first;
+  if (first) {{
+    first->prev = node_list.last;
+  }}
+
+  list->first          = node_list.first;
+  node_list.last->next = first;

codegen/dbl_list/snippets/list_remove

@@ -0,0 +1,28 @@
+  {T}Node *output = NULL;
+  if (!list) {{
+    goto RETURN_{Tupper}_LIST_REMOVE;
+  }}
+
+  if (index == 0) {{
+    output = wapp_str8_list_pop_front(list);
+    goto RETURN_{Tupper}_LIST_REMOVE;
+  }} else if (index == list->node_count) {{
+    output = wapp_str8_list_pop_back(list);
+    goto RETURN_{Tupper}_LIST_REMOVE;
+  }}
+
+  output = wapp_str8_list_get(list, index);
+  if (!output) {{
+    goto RETURN_{Tupper}_LIST_REMOVE;
+  }}
+
+  output->prev->next = output->next;
+  output->next->prev = output->prev;
+
+  --(list->node_count);
+  list->total_size -= output->string->size;
+
+  output->prev = output->next = NULL;
+
+RETURN_{Tupper}_LIST_REMOVE:
+  return output;

codegen/dbl_list/snippets/node_to_list

@@ -0,0 +1,15 @@
+  {T}List output = {{.first = node, .last = node, .total_size = node->string->size, .node_count = 1}};
+
+  while (output.first->prev != NULL) {{
+    output.total_size += output.first->prev->string->size;
+    output.first = output.first->prev;
+    ++(output.node_count);
+  }}
+
+  while (output.last->next != NULL) {{
+    output.total_size += output.last->next->string->size;
+    output.last = output.last->next;
+    ++(output.node_count);
+  }}
+
+  return output;