src/libgame/snapshot.c

   1 // ============================================================================
   2 // Artsoft Retro-Game Library
   3 // ----------------------------------------------------------------------------
   4 // (c) 1995-2014 by Artsoft Entertainment
   5 //                  Holger Schemel
   6 //                  info@artsoft.org
   7 //                  http://www.artsoft.org/
   8 // ----------------------------------------------------------------------------
   9 // snapshot.c
  10 // ============================================================================
  11
  12 #include "snapshot.h"
  13
  14
  15 static ListNode *snapshot_single = NULL;
  16 static ListNode *snapshot_list = NULL;
  17 static ListNode *snapshot_current = NULL;
  18
  19 static int num_snapshots_in_list = 0;
  20
  21
  22 #ifdef DEBUG
  23 #define DEBUG_SNAPSHOTS                 0
  24 #endif
  25
  26
  27 // -----------------------------------------------------------------------------
  28 // functions for handling buffers for a single snapshot
  29 // -----------------------------------------------------------------------------
  30
  31 void SaveSnapshotBuffer(ListNode **snapshot_buffers, void *buffer, int size)
  32 {
  33   struct SnapshotNodeInfo *bi =
  34     checked_calloc(sizeof(struct SnapshotNodeInfo));
  35
  36   bi->buffer_orig = buffer;
  37   bi->buffer_copy = checked_malloc(size);
  38   bi->size = size;
  39
  40   memcpy(bi->buffer_copy, buffer, size);
  41
  42   addNodeToList(snapshot_buffers, NULL, bi);
  43 }
  44
  45 static void LoadSnapshotBuffer(struct SnapshotNodeInfo *bi)
  46 {
  47   memcpy(bi->buffer_orig, bi->buffer_copy, bi->size);
  48 }
  49
  50 void LoadSnapshotBuffers(ListNode *snapshot_buffers)
  51 {
  52   while (snapshot_buffers != NULL)
  53   {
  54     LoadSnapshotBuffer((struct SnapshotNodeInfo *)snapshot_buffers->content);
  55
  56     snapshot_buffers = snapshot_buffers->next;
  57   }
  58 }
  59
  60 void FreeSnapshotBuffers(ListNode *snapshot_buffers)
  61 {
  62   while (snapshot_buffers != NULL)
  63     deleteNodeFromList(&snapshot_buffers, snapshot_buffers->key, checked_free);
  64 }
  65
  66 // -----------------------------------------------------------------------------
  67 // functions for handling one of several snapshots
  68 // -----------------------------------------------------------------------------
  69
  70 static void FreeSnapshotExt(void *snapshot_buffers_ptr)
  71 {
  72   FreeSnapshotBuffers(snapshot_buffers_ptr);
  73 }
  74
  75 void FreeSnapshotSingle()
  76 {
  77   FreeSnapshotBuffers(snapshot_single);
  78
  79   snapshot_single = NULL;
  80 }
  81
  82 void FreeSnapshotList_UpToNode(ListNode *node)
  83 {
  84   while (snapshot_list != node)
  85   {
  86     deleteNodeFromList(&snapshot_list, snapshot_list->key, FreeSnapshotExt);
  87
  88     num_snapshots_in_list--;
  89   }
  90 }
  91
  92 void FreeSnapshotList()
  93 {
  94   FreeSnapshotList_UpToNode(NULL);
  95
  96   snapshot_current = NULL;
  97 }
  98
  99 void SaveSnapshotSingle(ListNode *snapshot_buffers)
 100 {
 101   if (snapshot_single)
 102     FreeSnapshotSingle();
 103
 104   snapshot_single = snapshot_buffers;
 105 }
 106
 107 void SaveSnapshotToList(ListNode *snapshot_buffers)
 108 {
 109   if (snapshot_current != snapshot_list)
 110     FreeSnapshotList_UpToNode(snapshot_current);
 111
 112   addNodeToList(&snapshot_list, i_to_a(num_snapshots_in_list),
 113                 snapshot_buffers);
 114
 115   snapshot_current = snapshot_list;
 116
 117   num_snapshots_in_list++;
 118
 119 #if DEBUG_SNAPSHOTS
 120   printf("::: SaveSnapshotToList() [%s]\n", snapshot_current->key);
 121 #endif
 122 }
 123
 124 boolean LoadSnapshotSingle()
 125 {
 126   if (snapshot_single)
 127   {
 128     LoadSnapshotBuffers(snapshot_single);
 129
 130     return TRUE;
 131   }
 132
 133   return FALSE;
 134 }
 135
 136 boolean LoadSnapshotFromList_Older(int steps)
 137 {
 138   if (snapshot_current->next)
 139   {
 140     while (snapshot_current->next && steps--)
 141       snapshot_current = snapshot_current->next;
 142
 143     LoadSnapshotBuffers(snapshot_current->content);
 144
 145 #if DEBUG_SNAPSHOTS
 146     printf("::: LoadSnapshotFromList_Older() [%s]\n", snapshot_current->key);
 147 #endif
 148
 149     return TRUE;
 150   }
 151
 152   return FALSE;
 153 }
 154
 155 boolean LoadSnapshotFromList_Newer(int steps)
 156 {
 157   if (snapshot_current->prev)
 158   {
 159     while (snapshot_current->prev && steps--)
 160       snapshot_current = snapshot_current->prev;
 161
 162     LoadSnapshotBuffers(snapshot_current->content);
 163
 164 #if DEBUG_SNAPSHOTS
 165     printf("::: LoadSnapshotFromList_Newer() [%s]\n", snapshot_current->key);
 166 #endif
 167
 168     return TRUE;
 169   }
 170
 171   return FALSE;
 172 }