src/common/objstrm.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        objstrm.cpp
   3 // Purpose:     wxObjectStream classes
   4 // Author:      Guilhem Lavaux
   5 // Modified by:
   6 // Created:     16/07/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 1998 Guilhem Lavaux
   9 // Licence:     wxWindows license
  10 /////////////////////////////////////////////////////////////////////////////
  11 #ifdef __GNUG__
  12 #pragma implementation "objstrm.h"
  13 #endif
  14
  15 #include "wx/object.h"
  16 #include "wx/objstrm.h"
  17 #include "wx/datstrm.h"
  18
  19 #define WXOBJ_BEGIN "OBEGIN"
  20 #define WXOBJ_BEG_LEN 6
  21
  22 #define TAG_EMPTY_OBJECT "NULL"
  23 #define TAG_DUPLICATE_OBJECT "DUPLIC"
  24
  25 // ----------------------------------------------------------------------------
  26 // wxObjectOutputStream
  27 // ----------------------------------------------------------------------------
  28
  29 wxObjectOutputStream::wxObjectOutputStream(wxOutputStream& s)
  30   : wxFilterOutputStream(s)
  31 {
  32   m_saving = FALSE;
  33 }
  34
  35 wxString wxObjectOutputStream::GetObjectName(wxObject *obj)
  36 {
  37   wxString name;
  38
  39   name.Printf("%x", (unsigned long)obj);
  40   return name;
  41 }
  42
  43 void wxObjectOutputStream::WriteObjectDef(wxObjectStreamInfo& info)
  44 {
  45   wxDataOutputStream data_s(*this);
  46
  47   Write(WXOBJ_BEGIN, WXOBJ_BEG_LEN);
  48
  49   if (info.duplicate) {
  50     data_s.WriteString(TAG_DUPLICATE_OBJECT);
  51     data_s.WriteString(GetObjectName(info.object));
  52     return;
  53   }
  54
  55   if (info.object) {
  56     data_s.WriteString(info.object->GetClassInfo()->GetClassName());
  57   } else {
  58     data_s.WriteString(TAG_EMPTY_OBJECT);
  59     return;
  60   }
  61
  62   data_s.WriteString(GetObjectName(info.object));
  63
  64   // I assume an object will not have millions of children
  65   // Hmmm ... it could have (for example wxGrid)
  66   data_s.Write32(info.children.Number());
  67 }
  68
  69 void wxObjectOutputStream::AddChild(wxObject *obj)
  70 {
  71   wxObjectStreamInfo *info;
  72
  73   if (!FirstStage())
  74     return;
  75
  76   info = new wxObjectStreamInfo;
  77
  78   if (m_saved_objs.Member(obj) != NULL) {
  79     info->duplicate = TRUE;
  80   } else {
  81     info->duplicate = FALSE;
  82     m_saved_objs.Append(obj);
  83   }
  84   if (!obj)
  85     info->duplicate = FALSE;
  86
  87   info->n_children = 0;
  88   info->object = obj;
  89   info->parent = m_current_info; // Not useful here.
  90   m_current_info->n_children++;
  91   m_current_info->children.Append(info);
  92 }
  93
  94 void wxObjectOutputStream::ProcessObjectDef(wxObjectStreamInfo *info)
  95 {
  96   wxNode *node;
  97
  98   m_current_info = info;
  99   // First stage: get children of obj
 100   if (info->object && !info->duplicate)
 101     info->object->StoreObject(*this);
 102
 103   // Prepare and write the sub-entry about the child obj.
 104   WriteObjectDef(*info);
 105
 106   node = info->children.First();
 107
 108   while (node) {
 109     ProcessObjectDef((wxObjectStreamInfo *)node->Data());
 110     node = node->Next();
 111   }
 112 }
 113
 114 void wxObjectOutputStream::ProcessObjectData(wxObjectStreamInfo *info)
 115 {
 116   wxNode *node = info->children.First();
 117
 118   m_current_info = info;
 119
 120   if (info->object && !info->duplicate)
 121     info->object->StoreObject(*this);
 122
 123   while (node) {
 124     ProcessObjectData((wxObjectStreamInfo *)node->Data());
 125     node = node->Next();
 126   }
 127 }
 128
 129 bool wxObjectOutputStream::SaveObject(wxObject& obj)
 130 {
 131   wxObjectStreamInfo info;
 132
 133   if (m_saving)
 134     return FALSE;
 135
 136   m_saving = TRUE;
 137
 138   // First stage
 139   m_stage = 0;
 140   info.object = &obj;
 141   info.n_children = 0;
 142   info.duplicate = FALSE;
 143   ProcessObjectDef(&info);
 144
 145   m_stage = 1;
 146   ProcessObjectData(&info);
 147
 148   info.children.Clear();
 149   m_saved_objs.Clear();
 150
 151   m_saving = FALSE;
 152
 153   return TRUE;
 154 }
 155
 156 // ----------------------------------------------------------------------------
 157 // wxObjectInputStream
 158 // ----------------------------------------------------------------------------
 159
 160 wxObjectInputStream::wxObjectInputStream(wxInputStream& s)
 161   : wxFilterInputStream(s)
 162 {
 163 }
 164
 165 wxObject *wxObjectInputStream::SolveName(const wxString& name) const
 166 {
 167   wxNode *node = m_solver.First();
 168   wxObjectStreamInfo *info;
 169
 170   while (node) {
 171     info = (wxObjectStreamInfo *)node->Data();
 172     if (info->object_name == name)
 173       return info->object;
 174
 175     node = node->Next();
 176   }
 177   return (wxObject *) NULL;
 178 }
 179
 180 wxObject *wxObjectInputStream::GetParent() const
 181 {
 182   if (!m_current_info->parent)
 183     return (wxObject *) NULL;
 184
 185   return m_current_info->parent->object;
 186 }
 187
 188 wxObject *wxObjectInputStream::GetChild()
 189 {
 190   wxObject *obj = GetChild(0);
 191
 192   m_current_info->children_removed++;
 193
 194   return obj;
 195 }
 196
 197 wxObject *wxObjectInputStream::GetChild(int no) const
 198 {
 199   wxNode *node;
 200   wxObjectStreamInfo *info;
 201
 202   if (m_current_info->children_removed >= m_current_info->n_children)
 203     return NULL;
 204
 205   node = m_current_info->children.Nth(m_current_info->children_removed+no);
 206
 207   if (!node)
 208     return (wxObject *) NULL;
 209
 210   info = (wxObjectStreamInfo *)node->Data();
 211
 212   return info->object;
 213 }
 214
 215 void wxObjectInputStream::RemoveChildren(int nb)
 216 {
 217   m_current_info->children_removed += nb;
 218 }
 219
 220 bool wxObjectInputStream::ReadObjectDef(wxObjectStreamInfo *info)
 221 {
 222   wxDataInputStream data_s(*this);
 223   char sig[WXOBJ_BEG_LEN+1];
 224   wxString class_name;
 225
 226   Read(sig, WXOBJ_BEG_LEN);
 227   sig[WXOBJ_BEG_LEN] = 0;
 228   if (wxString(sig) != WXOBJ_BEGIN)
 229     return FALSE;
 230
 231   class_name = data_s.ReadString();
 232   info->children_removed = 0;
 233
 234   if (class_name == TAG_EMPTY_OBJECT)
 235     info->object = (wxObject *) NULL;
 236   else if (class_name == TAG_DUPLICATE_OBJECT) {
 237     info->object_name = data_s.ReadString();
 238     info->object = SolveName(info->object_name);
 239     info->n_children = 0;
 240   } else {
 241     info->object_name = data_s.ReadString();
 242     info->object = wxCreateDynamicObject( WXSTRINGCAST class_name);
 243     info->n_children = data_s.Read32();
 244   }
 245   return TRUE;
 246 }
 247
 248 wxObjectStreamInfo *wxObjectInputStream::ProcessObjectDef(wxObjectStreamInfo *parent)
 249 {
 250   wxObjectStreamInfo *info, *c_info;
 251   int c;
 252
 253   info = new wxObjectStreamInfo;
 254   info->parent = parent;
 255   info->children.DeleteContents(TRUE);
 256
 257   m_solver.Append(info);
 258
 259   if (!ReadObjectDef(info))
 260     return (wxObjectStreamInfo *) NULL;
 261
 262   for (c=0;c<info->n_children;c++) {
 263     c_info = ProcessObjectDef(info);
 264     if (!c_info)
 265       return (wxObjectStreamInfo *) NULL;
 266     info->children.Append(c_info);
 267   }
 268
 269   return info;
 270 }
 271
 272 void wxObjectInputStream::ProcessObjectData(wxObjectStreamInfo *info)
 273 {
 274   wxNode *node = info->children.First();
 275
 276   m_current_info = info;
 277
 278   if (info->object)
 279     info->object->LoadObject(*this);
 280   while (node) {
 281     ProcessObjectData((wxObjectStreamInfo *)node->Data());
 282     node = node->Next();
 283   }
 284
 285   m_current_info = info;
 286
 287   if (info->recall) {
 288     m_secondcall = TRUE;
 289     info->object->LoadObject(*this);
 290     m_secondcall = FALSE;
 291   }
 292 }
 293
 294 wxObject *wxObjectInputStream::LoadObject()
 295 {
 296   wxObjectStreamInfo *info;
 297   wxObject *object;
 298
 299   info = ProcessObjectDef((wxObjectStreamInfo *) NULL);
 300   if (!info)
 301     return (wxObject *) NULL;
 302   ProcessObjectData(info);
 303
 304   object = info->object;
 305
 306   delete info; // It's magic ! The whole tree is destroyed.
 307
 308   return object;
 309 }