src/game/level/level_editor/undo_history.c

   1 #include <stdlib.h>
   2 #include <stdio.h>
   3
   4 #include <SDL.h>
   5
   6 #include "system/nth_alloc.h"
   7 #include "system/stacktrace.h"
   8 #include "undo_history.h"
   9 #include "config.h"
  10
  11 typedef struct {
  12     RevertAction revert;
  13     void *context_data;
  14     size_t context_data_size;
  15 } HistoryItem;
  16
  17 UndoHistory *create_undo_history(Memory *memory)
  18 {
  19     UndoHistory *result = memory_alloc(memory, sizeof(UndoHistory));
  20     result->actions = create_ring_buffer_from_buffer(
  21         memory,
  22         sizeof(HistoryItem),
  23         UNDO_HISTORY_CAPACITY);
  24     result->memory = memory;
  25     return result;
  26 }
  27
  28 void undo_history_push(UndoHistory *undo_history,
  29                        RevertAction revert,
  30                        void *context_data,
  31                        size_t context_data_size)
  32 {
  33     trace_assert(undo_history);
  34
  35     // TODO: undo_history_push kinda leaks the memory
  36     HistoryItem item = {
  37         .revert = revert,
  38         .context_data = memory_alloc(undo_history->memory, context_data_size),
  39         .context_data_size = context_data_size
  40     };
  41     memcpy(item.context_data, context_data, context_data_size);
  42     ring_buffer_push(&undo_history->actions, &item);
  43 }
  44
  45 void undo_history_pop(UndoHistory *undo_history)
  46 {
  47     trace_assert(undo_history);
  48
  49     if (undo_history->actions.count > 0) {
  50         HistoryItem *item = ring_buffer_top(&undo_history->actions);
  51         item->revert(item->context_data, item->context_data_size);
  52         ring_buffer_pop(&undo_history->actions);
  53     }
  54 }
  55
  56 void undo_history_clean(UndoHistory *undo_history)
  57 {
  58     trace_assert(undo_history);
  59
  60     while (undo_history->actions.count) {
  61         ring_buffer_pop(&undo_history->actions);
  62     }
  63 }