dlls/ole32/git.c

   1 /*
   2  * Implementation of the StdGlobalInterfaceTable object
   3  *
   4  * The GlobalInterfaceTable (GIT) object is used to marshal interfaces between
   5  * threading apartments (contexts). When you want to pass an interface but not
   6  * as a parameter, it wouldn't get marshalled automatically, so you can use this
   7  * object to insert the interface into a table, and you get back a cookie.
   8  * Then when it's retrieved, it'll be unmarshalled into the right apartment.
   9  *
  10  * Copyright 2003 Mike Hearn <mike@theoretic.com>
  11  *
  12  * This library is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU Lesser General Public
  14  * License as published by the Free Software Foundation; either
  15  * version 2.1 of the License, or (at your option) any later version.
  16  *
  17  * This library is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  20  * Lesser General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU Lesser General Public
  23  * License along with this library; if not, write to the Free Software
  24  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  25  */
  26
  27 #include <stdarg.h>
  28
  29 #define COBJMACROS
  30
  31 #include "windef.h"
  32 #include "winbase.h"
  33 #include "winuser.h"
  34 #include "objbase.h"
  35 #include "ole2.h"
  36 #include "winerror.h"
  37
  38 #include "compobj_private.h"
  39
  40 #include "wine/list.h"
  41 #include "wine/debug.h"
  42
  43 WINE_DEFAULT_DEBUG_CHANNEL(ole);
  44
  45 /****************************************************************************
  46  * StdGlobalInterfaceTable definition
  47  *
  48  * This class implements IGlobalInterfaceTable and is a process-wide singleton
  49  * used for marshalling interfaces between threading apartments using cookies.
  50  */
  51
  52 /* Each entry in the linked list of GIT entries */
  53 typedef struct StdGITEntry
  54 {
  55   DWORD cookie;
  56   IID iid;         /* IID of the interface */
  57   IStream* stream; /* Holds the marshalled interface */
  58
  59   struct list entry;
  60 } StdGITEntry;
  61
  62 /* Class data */
  63 typedef struct StdGlobalInterfaceTableImpl
  64 {
  65   IGlobalInterfaceTable IGlobalInterfaceTable_iface;
  66
  67   struct list list;
  68   ULONG nextCookie;
  69
  70 } StdGlobalInterfaceTableImpl;
  71
  72 static IGlobalInterfaceTable *std_git;
  73
  74 static CRITICAL_SECTION git_section;
  75 static CRITICAL_SECTION_DEBUG critsect_debug =
  76 {
  77     0, 0, &git_section,
  78     { &critsect_debug.ProcessLocksList, &critsect_debug.ProcessLocksList },
  79       0, 0, { (DWORD_PTR)(__FILE__ ": global interface table") }
  80 };
  81 static CRITICAL_SECTION git_section = { &critsect_debug, -1, 0, 0, 0, 0 };
  82
  83
  84 static inline StdGlobalInterfaceTableImpl *impl_from_IGlobalInterfaceTable(IGlobalInterfaceTable *iface)
  85 {
  86   return CONTAINING_RECORD(iface, StdGlobalInterfaceTableImpl, IGlobalInterfaceTable_iface);
  87 }
  88
  89 /***
  90  * A helper function to traverse the list and find the entry that matches the cookie.
  91  * Returns NULL if not found. Must be called inside git_section critical section.
  92  */
  93 static StdGITEntry* StdGlobalInterfaceTable_FindEntry(StdGlobalInterfaceTableImpl* This,
  94                 DWORD cookie)
  95 {
  96   StdGITEntry* e;
  97
  98   TRACE("This=%p, cookie=0x%x\n", This, cookie);
  99
 100   LIST_FOR_EACH_ENTRY(e, &This->list, StdGITEntry, entry) {
 101     if (e->cookie == cookie)
 102       return e;
 103   }
 104
 105   TRACE("Entry not found\n");
 106   return NULL;
 107 }
 108
 109 /***
 110  * Here's the boring boilerplate stuff for IUnknown
 111  */
 112
 113 static HRESULT WINAPI
 114 StdGlobalInterfaceTable_QueryInterface(IGlobalInterfaceTable* iface,
 115                REFIID riid, void** ppvObject)
 116 {
 117   /* Make sure silly coders can't crash us */
 118   if (ppvObject == 0) return E_INVALIDARG;
 119
 120   *ppvObject = 0; /* assume we don't have the interface */
 121
 122   /* Do we implement that interface? */
 123   if (IsEqualIID(&IID_IUnknown, riid) ||
 124       IsEqualIID(&IID_IGlobalInterfaceTable, riid))
 125   {
 126     *ppvObject = iface;
 127   }
 128   else
 129   {
 130     FIXME("(%s), not supported.\n", debugstr_guid(riid));
 131     return E_NOINTERFACE;
 132   }
 133
 134   /* Now inc the refcount */
 135   IGlobalInterfaceTable_AddRef(iface);
 136   return S_OK;
 137 }
 138
 139 static ULONG WINAPI
 140 StdGlobalInterfaceTable_AddRef(IGlobalInterfaceTable* iface)
 141 {
 142   return 1;
 143 }
 144
 145 static ULONG WINAPI
 146 StdGlobalInterfaceTable_Release(IGlobalInterfaceTable* iface)
 147 {
 148   return 1;
 149 }
 150
 151 /***
 152  * Now implement the actual IGlobalInterfaceTable interface
 153  */
 154
 155 static HRESULT WINAPI
 156 StdGlobalInterfaceTable_RegisterInterfaceInGlobal(
 157                IGlobalInterfaceTable* iface, IUnknown* pUnk,
 158                REFIID riid, DWORD* pdwCookie)
 159 {
 160   StdGlobalInterfaceTableImpl* const This = impl_from_IGlobalInterfaceTable(iface);
 161   IStream* stream = NULL;
 162   HRESULT hres;
 163   StdGITEntry* entry;
 164   LARGE_INTEGER zero;
 165
 166   TRACE("iface=%p, pUnk=%p, riid=%s, pdwCookie=0x%p\n", iface, pUnk, debugstr_guid(riid), pdwCookie);
 167
 168   if (pUnk == NULL) return E_INVALIDARG;
 169
 170   /* marshal the interface */
 171   TRACE("About to marshal the interface\n");
 172
 173   hres = CreateStreamOnHGlobal(0, TRUE, &stream);
 174   if (hres != S_OK) return hres;
 175   hres = CoMarshalInterface(stream, riid, pUnk, MSHCTX_INPROC, NULL, MSHLFLAGS_TABLESTRONG);
 176   if (hres != S_OK)
 177   {
 178     IStream_Release(stream);
 179     return hres;
 180   }
 181
 182   zero.QuadPart = 0;
 183   IStream_Seek(stream, zero, STREAM_SEEK_SET, NULL);
 184
 185   entry = HeapAlloc(GetProcessHeap(), 0, sizeof(StdGITEntry));
 186   if (!entry)
 187   {
 188       CoReleaseMarshalData(stream);
 189       IStream_Release(stream);
 190       return E_OUTOFMEMORY;
 191   }
 192
 193   EnterCriticalSection(&git_section);
 194
 195   entry->iid = *riid;
 196   entry->stream = stream;
 197   entry->cookie = This->nextCookie;
 198   This->nextCookie++; /* inc the cookie count */
 199
 200   /* insert the new entry at the end of the list */
 201   list_add_tail(&This->list, &entry->entry);
 202
 203   /* and return the cookie */
 204   *pdwCookie = entry->cookie;
 205
 206   LeaveCriticalSection(&git_section);
 207
 208   TRACE("Cookie is 0x%x\n", entry->cookie);
 209   return S_OK;
 210 }
 211
 212 static HRESULT WINAPI
 213 StdGlobalInterfaceTable_RevokeInterfaceFromGlobal(
 214                IGlobalInterfaceTable* iface, DWORD dwCookie)
 215 {
 216   StdGlobalInterfaceTableImpl* This = impl_from_IGlobalInterfaceTable(iface);
 217   StdGITEntry* entry;
 218   HRESULT hr;
 219
 220   TRACE("iface=%p, dwCookie=0x%x\n", iface, dwCookie);
 221
 222   EnterCriticalSection(&git_section);
 223
 224   entry = StdGlobalInterfaceTable_FindEntry(This, dwCookie);
 225   if (entry == NULL) {
 226     TRACE("Entry not found\n");
 227     LeaveCriticalSection(&git_section);
 228     return E_INVALIDARG; /* not found */
 229   }
 230
 231   list_remove(&entry->entry);
 232
 233   LeaveCriticalSection(&git_section);
 234
 235   /* Free the stream */
 236   hr = CoReleaseMarshalData(entry->stream);
 237   if (hr != S_OK)
 238   {
 239     WARN("Failed to release marshal data, hr = 0x%08x\n", hr);
 240     return hr;
 241   }
 242   IStream_Release(entry->stream);
 243
 244   HeapFree(GetProcessHeap(), 0, entry);
 245   return S_OK;
 246 }
 247
 248 static HRESULT WINAPI
 249 StdGlobalInterfaceTable_GetInterfaceFromGlobal(
 250                IGlobalInterfaceTable* iface, DWORD dwCookie,
 251                REFIID riid, void **ppv)
 252 {
 253   StdGlobalInterfaceTableImpl* This = impl_from_IGlobalInterfaceTable(iface);
 254   StdGITEntry* entry;
 255   HRESULT hres;
 256   IStream *stream;
 257
 258   TRACE("dwCookie=0x%x, riid=%s, ppv=%p\n", dwCookie, debugstr_guid(riid), ppv);
 259
 260   EnterCriticalSection(&git_section);
 261
 262   entry = StdGlobalInterfaceTable_FindEntry(This, dwCookie);
 263   if (entry == NULL) {
 264     WARN("Entry for cookie 0x%x not found\n", dwCookie);
 265     LeaveCriticalSection(&git_section);
 266     return E_INVALIDARG;
 267   }
 268
 269   TRACE("entry=%p\n", entry);
 270
 271   hres = IStream_Clone(entry->stream, &stream);
 272
 273   LeaveCriticalSection(&git_section);
 274
 275   if (hres != S_OK) {
 276     WARN("Failed to clone stream with error 0x%08x\n", hres);
 277     return hres;
 278   }
 279
 280   /* unmarshal the interface */
 281   hres = CoUnmarshalInterface(stream, riid, ppv);
 282   IStream_Release(stream);
 283
 284   if (hres != S_OK) {
 285     WARN("Failed to unmarshal stream\n");
 286     return hres;
 287   }
 288
 289   TRACE("ppv=%p\n", *ppv);
 290   return S_OK;
 291 }
 292
 293 static const IGlobalInterfaceTableVtbl StdGlobalInterfaceTableImpl_Vtbl =
 294 {
 295     StdGlobalInterfaceTable_QueryInterface,
 296     StdGlobalInterfaceTable_AddRef,
 297     StdGlobalInterfaceTable_Release,
 298     StdGlobalInterfaceTable_RegisterInterfaceInGlobal,
 299     StdGlobalInterfaceTable_RevokeInterfaceFromGlobal,
 300     StdGlobalInterfaceTable_GetInterfaceFromGlobal
 301 };
 302
 303 HRESULT WINAPI GlobalInterfaceTable_CreateInstance(IClassFactory *iface, IUnknown *outer, REFIID riid, void **obj)
 304 {
 305     StdGlobalInterfaceTableImpl *git;
 306
 307     if (!std_git)
 308     {
 309         git = heap_alloc(sizeof(*git));
 310         if (!git) return E_OUTOFMEMORY;
 311
 312         git->IGlobalInterfaceTable_iface.lpVtbl = &StdGlobalInterfaceTableImpl_Vtbl;
 313         list_init(&git->list);
 314         git->nextCookie = 0xf100; /* that's where windows starts, so that's where we start */
 315
 316         if (InterlockedCompareExchangePointer((void **)&std_git, &git->IGlobalInterfaceTable_iface, NULL))
 317         {
 318             heap_free(git);
 319         }
 320         else
 321             TRACE("Created the GIT %p\n", git);
 322     }
 323
 324     return IGlobalInterfaceTable_QueryInterface(std_git, riid, obj);
 325 }
 326
 327 void release_std_git(void)
 328 {
 329   StdGlobalInterfaceTableImpl *git;
 330   StdGITEntry *entry, *entry2;
 331
 332   if (!std_git) return;
 333
 334   git = impl_from_IGlobalInterfaceTable(std_git);
 335   LIST_FOR_EACH_ENTRY_SAFE(entry, entry2, &git->list, StdGITEntry, entry)
 336   {
 337       list_remove(&entry->entry);
 338
 339       CoReleaseMarshalData(entry->stream);
 340       IStream_Release(entry->stream);
 341       HeapFree(GetProcessHeap(), 0, entry);
 342   }
 343
 344   HeapFree(GetProcessHeap(), 0, git);
 345 }