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   }
  60
  61   data_s.WriteString(GetObjectName(info.object));
  62
  63   // I assume an object will not have millions of children
  64   // Hmmm ... it could have (for example wxGrid)
  65   data_s.Write32(info.children.Number());
  66 }
  67
  68 void wxObjectOutputStream::AddChild(wxObject *obj)
  69 {
  70   wxObjectStreamInfo *info;
  71
  72   if (!FirstStage())
  73     return;
  74
  75   info = new wxObjectStreamInfo;
  76
  77   if (m_saved_objs.Member(obj) != NULL) {
  78     info->duplicate = TRUE;
  79   } else {
  80     info->duplicate = FALSE;
  81     m_saved_objs.Append(obj);
  82   }
  83   info->n_children = 0;
  84   info->object = obj;
  85   info->parent = m_current_info; // Not useful here.
  86   m_current_info->n_children++;
  87   m_current_info->children.Append(info);
  88 }
  89
  90 void wxObjectOutputStream::ProcessObjectDef(wxObjectStreamInfo *info)
  91 {
  92   wxNode *node;
  93
  94   m_current_info = info;
  95   // First stage: get children of obj
  96   if (info->object && !info->duplicate)
  97     info->object->StoreObject(*this);
  98
  99   // Prepare and write the sub-entry about the child obj.
 100   WriteObjectDef(*info);
 101
 102   node = info->children.First();
 103
 104   while (node) {
 105     ProcessObjectDef((wxObjectStreamInfo *)node->Data());
 106     node = node->Next();
 107   }
 108 }
 109
 110 void wxObjectOutputStream::ProcessObjectData(wxObjectStreamInfo *info)
 111 {
 112   wxNode *node = info->children.First();
 113
 114   m_current_info = info;
 115
 116   if (info->object && !info->duplicate)
 117     info->object->StoreObject(*this);
 118
 119   while (node) {
 120     ProcessObjectData((wxObjectStreamInfo *)node->Data());
 121     node = node->Next();
 122   }
 123 }
 124
 125 bool wxObjectOutputStream::SaveObject(wxObject& obj)
 126 {
 127   wxObjectStreamInfo info;
 128
 129   if (m_saving)
 130     return FALSE;
 131
 132   m_saving = TRUE;
 133
 134   // First stage
 135   m_stage = 0;
 136   info.object = &obj;
 137   info.n_children = 0;
 138   ProcessObjectDef(&info);
 139
 140   m_stage = 1;
 141   ProcessObjectData(&info);
 142
 143   info.children.Clear();
 144   m_saved_objs.Clear();
 145
 146   m_saving = FALSE;
 147
 148   return TRUE;
 149 }
 150
 151 // ----------------------------------------------------------------------------
 152 // wxObjectInputStream
 153 // ----------------------------------------------------------------------------
 154
 155 wxObjectInputStream::wxObjectInputStream(wxInputStream& s)
 156   : wxFilterInputStream(s)
 157 {
 158 }
 159
 160 wxObject *wxObjectInputStream::SolveName(const wxString& name) const
 161 {
 162   wxNode *node = m_solver.First();
 163   wxObjectStreamInfo *info;
 164
 165   while (node) {
 166     info = (wxObjectStreamInfo *)node->Data();
 167     if (info->object_name == name)
 168       return info->object;
 169
 170     node = node->Next();
 171   }
 172   return NULL;
 173 }
 174
 175 wxObject *wxObjectInputStream::GetParent() const
 176 {
 177   if (!m_current_info->parent)
 178     return NULL;
 179
 180   return m_current_info->parent->object;
 181 }
 182
 183 wxObject *wxObjectInputStream::GetChild(int no) const
 184 {
 185   wxNode *node = m_current_info->children.Nth(m_current_info->children_removed+no);
 186   wxObjectStreamInfo *info;
 187
 188   if (!node)
 189     return NULL;
 190
 191   info = (wxObjectStreamInfo *)node->Data();
 192
 193   return info->object;
 194 }
 195
 196 void wxObjectInputStream::RemoveChildren(int nb)
 197 {
 198   m_current_info->children_removed += nb;
 199 }
 200
 201 bool wxObjectInputStream::ReadObjectDef(wxObjectStreamInfo *info)
 202 {
 203   wxDataInputStream data_s(*this);
 204   char sig[WXOBJ_BEG_LEN+1];
 205   wxString class_name;
 206
 207   Read(sig, WXOBJ_BEG_LEN);
 208   sig[WXOBJ_BEG_LEN] = 0;
 209   if (wxString(sig) != WXOBJ_BEGIN)
 210     return FALSE;
 211
 212   class_name = data_s.ReadString();
 213   info->object_name = data_s.ReadString();
 214   info->children_removed = 0;
 215
 216   if (class_name == TAG_EMPTY_OBJECT)
 217     info->object = NULL;
 218   else if (class_name == TAG_DUPLICATE_OBJECT) {
 219     info->object = SolveName(info->object_name);
 220     info->n_children = 0;
 221   } else {
 222     info->object = wxCreateDynamicObject( WXSTRINGCAST class_name);
 223     info->n_children = data_s.Read8();
 224   }
 225   return TRUE;
 226 }
 227
 228 wxObjectStreamInfo *wxObjectInputStream::ProcessObjectDef(wxObjectStreamInfo *parent)
 229 {
 230   wxObjectStreamInfo *info, *c_info;
 231   int c;
 232
 233   info = new wxObjectStreamInfo;
 234   info->parent = parent;
 235   info->children.DeleteContents(TRUE);
 236
 237   m_solver.Append(info);
 238
 239   if (!ReadObjectDef(info))
 240     return NULL;
 241
 242   for (c=0;c<info->n_children;c++) {
 243     c_info = ProcessObjectDef(info);
 244     if (!c_info)
 245       return NULL;
 246     info->children.Append(c_info);
 247   }
 248
 249   return info;
 250 }
 251
 252 void wxObjectInputStream::ProcessObjectData(wxObjectStreamInfo *info)
 253 {
 254   wxNode *node = info->children.First();
 255
 256   m_current_info = info;
 257
 258   if (info->object)
 259     info->object->LoadObject(*this);
 260   while (node) {
 261     ProcessObjectData((wxObjectStreamInfo *)node->Data());
 262     node = node->Next();
 263   }
 264 }
 265
 266 wxObject *wxObjectInputStream::LoadObject()
 267 {
 268   wxObjectStreamInfo *info;
 269   wxObject *object;
 270
 271   info = ProcessObjectDef(NULL);
 272   if (!info)
 273     return NULL;
 274   ProcessObjectData(info);
 275
 276   object = info->object;
 277
 278   delete info; // It's magic ! The whole tree is destroyed.
 279
 280   return object;
 281 }