dlls/shlwapi/clist.c

   1 /*
   2  * SHLWAPI DataBlock List functions
   3  *
   4  * Copyright 2002 Jon Griffiths
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  19  */
  20 #include <stdarg.h>
  21 #include <string.h>
  22
  23 #define COBJMACROS
  24
  25 #include "windef.h"
  26 #include "winbase.h"
  27 #include "winuser.h"
  28 #include "objbase.h"
  29 #include "shlobj.h"
  30 #include "wine/debug.h"
  31
  32 WINE_DEFAULT_DEBUG_CHANNEL(shell);
  33
  34 /* dwSignature for contained DATABLOCK_HEADER items */
  35 #define CLIST_ID_CONTAINER (~0U)
  36
  37 /*************************************************************************
  38  * NextItem
  39  *
  40  * Internal helper: move a DataBlock pointer to the next item.
  41  */
  42 static inline LPDATABLOCK_HEADER NextItem(LPDBLIST lpList)
  43 {
  44   char* address = (char*)lpList;
  45   address += lpList->cbSize;
  46   return (LPDATABLOCK_HEADER)address;
  47 }
  48
  49 /*************************************************************************
  50  *      @       [SHLWAPI.20]
  51  *
  52  * Insert a new item into a DataBlock list.
  53  *
  54  * PARAMS
  55  *  lppList   [0] Pointer to the List
  56  *  lpNewItem [I] The new item to add to the list
  57  *
  58  * RETURNS
  59  *  Success: S_OK. The item is added to the list.
  60  *  Failure: An HRESULT error code.
  61  *
  62  * NOTES
  63  *  If the size of the element to be inserted is less than the size of a
  64  *  DATABLOCK_HEADER node, or the Id for the item is CLIST_ID_CONTAINER,
  65  *  the call returns S_OK but does not actually add the element.
  66  *  See SHWriteDataBlockList.
  67  */
  68 HRESULT WINAPI SHAddDataBlock(LPDBLIST* lppList, const DATABLOCK_HEADER *lpNewItem)
  69 {
  70   LPDATABLOCK_HEADER lpInsertAt = NULL;
  71   ULONG ulSize;
  72
  73   TRACE("(%p,%p)\n", lppList, lpNewItem);
  74
  75   if(!lppList || !lpNewItem )
  76     return E_INVALIDARG;
  77
  78   if (lpNewItem->cbSize < sizeof(DATABLOCK_HEADER) ||
  79       lpNewItem->dwSignature == CLIST_ID_CONTAINER)
  80     return S_OK;
  81
  82   ulSize = lpNewItem->cbSize;
  83
  84   if(ulSize & 0x3)
  85   {
  86     /* Tune size to a ULONG boundary, add space for container element */
  87     ulSize = ((ulSize + 0x3) & 0xFFFFFFFC) + sizeof(DATABLOCK_HEADER);
  88     TRACE("Creating container item, new size = %d\n", ulSize);
  89   }
  90
  91   if(!*lppList)
  92   {
  93     /* An empty list. Allocate space for terminal ulSize also */
  94     *lppList = (LPDATABLOCK_HEADER)LocalAlloc(LMEM_ZEROINIT,
  95                                            ulSize + sizeof(ULONG));
  96     lpInsertAt = *lppList;
  97   }
  98   else
  99   {
 100     /* Append to the end of the list */
 101     ULONG ulTotalSize = 0;
 102     LPDATABLOCK_HEADER lpIter = *lppList;
 103
 104     /* Iterate to the end of the list, calculating the total size */
 105     while (lpIter->cbSize)
 106     {
 107       ulTotalSize += lpIter->cbSize;
 108       lpIter = NextItem(lpIter);
 109     }
 110
 111     /* Increase the size of the list */
 112     lpIter = (LPDATABLOCK_HEADER)LocalReAlloc((HLOCAL)*lppList,
 113                                           ulTotalSize + ulSize+sizeof(ULONG),
 114                                           LMEM_ZEROINIT | LMEM_MOVEABLE);
 115     if(lpIter)
 116     {
 117       *lppList = lpIter;
 118       lpInsertAt = (LPDATABLOCK_HEADER)((char*)lpIter + ulTotalSize); /* At end */
 119     }
 120   }
 121
 122   if(lpInsertAt)
 123   {
 124     /* Copy in the new item */
 125     LPDATABLOCK_HEADER lpDest = lpInsertAt;
 126
 127     if(ulSize != lpNewItem->cbSize)
 128     {
 129       lpInsertAt->cbSize = ulSize;
 130       lpInsertAt->dwSignature = CLIST_ID_CONTAINER;
 131       lpDest++;
 132     }
 133     memcpy(lpDest, lpNewItem, lpNewItem->cbSize);
 134
 135     /* Terminate the list */
 136     lpInsertAt = NextItem(lpInsertAt);
 137     lpInsertAt->cbSize = 0;
 138
 139     return lpNewItem->cbSize;
 140   }
 141   return S_OK;
 142 }
 143
 144 /*************************************************************************
 145  *      @       [SHLWAPI.17]
 146  *
 147  * Write a DataBlock list to an IStream object.
 148  *
 149  * PARAMS
 150  *  lpStream  [I] IStream object to write the list to
 151  *  lpList    [I] List of items to write
 152  *
 153  * RETURNS
 154  *  Success: S_OK. The object is written to the stream.
 155  *  Failure: An HRESULT error code
 156  *
 157  * NOTES
 158  *  Ordinals 17,18,19,20,21 and 22 are related and together provide a compact
 159  *  list structure (a "DataBlock List"), which may be stored and retrieved from
 160  *  an IStream object.
 161  *
 162  *  The exposed API consists of:
 163  *
 164  *  - SHWriteDataBlockList() - Write a DataBlock list to a stream,
 165  *  - SHReadDataBlockList() - Read and create a list from a stream,
 166  *  - SHFreeDataBlockList() - Free a list,
 167  *  - SHAddDataBlock() - Insert a new item into a list,
 168  *  - SHRemoveDataBlock() - Remove an item from a list,
 169  *  - SHFindDataBlock() - Find an item in a list.
 170  *
 171  *  The DataBlock list is stored packed into a memory array. Each element has a
 172  *  size and an associated ID. Elements must be less than 64k if the list is
 173  *  to be subsequently read from a stream.
 174  *
 175  *  Elements are aligned on DWORD boundaries. If an elements data size is not
 176  *  a DWORD size multiple, the element is wrapped by inserting a surrounding
 177  *  element with an Id of 0xFFFFFFFF, and size sufficient to pad to a DWORD boundary.
 178  *
 179  *  These functions are slow for large objects and long lists.
 180  */
 181 HRESULT WINAPI SHWriteDataBlockList(IStream* lpStream, LPDBLIST lpList)
 182 {
 183   ULONG ulSize;
 184   HRESULT hRet = S_OK;
 185
 186   TRACE("(%p,%p)\n", lpStream, lpList);
 187
 188   if(lpList)
 189   {
 190     while (lpList->cbSize)
 191     {
 192       LPDATABLOCK_HEADER lpItem = lpList;
 193
 194       if(lpList->dwSignature == CLIST_ID_CONTAINER)
 195         lpItem++;
 196
 197       hRet = IStream_Write(lpStream,lpItem,lpItem->cbSize,&ulSize);
 198       if (FAILED(hRet))
 199         return hRet;
 200
 201       if(lpItem->cbSize != ulSize)
 202         return STG_E_MEDIUMFULL;
 203
 204       lpList = NextItem(lpList);
 205     }
 206   }
 207
 208   if(SUCCEEDED(hRet))
 209   {
 210     ULONG ulDummy;
 211     ulSize = 0;
 212
 213     /* Write a terminating list entry with zero size */
 214     hRet = IStream_Write(lpStream, &ulSize,sizeof(ulSize),&ulDummy);
 215   }
 216
 217   return hRet;
 218 }
 219
 220 /*************************************************************************
 221  *      @       [SHLWAPI.18]
 222  *
 223  * Read and create a DataBlock list from an IStream object.
 224  *
 225  * PARAMS
 226  *  lpStream  [I] Stream to read the list from
 227  *  lppList   [0] Pointer to receive the new List
 228  *
 229  * RETURNS
 230  *  Success: S_OK
 231  *  Failure: An HRESULT error code
 232  *
 233  * NOTES
 234  *  When read from a file, list objects are limited in size to 64k.
 235  *  See SHWriteDataBlockList.
 236  */
 237 HRESULT WINAPI SHReadDataBlockList(IStream* lpStream, LPDBLIST* lppList)
 238 {
 239   DATABLOCK_HEADER bBuff[128]; /* Temporary storage for new list item */
 240   ULONG ulBuffSize = sizeof(bBuff);
 241   LPDATABLOCK_HEADER pItem = bBuff;
 242   ULONG ulRead, ulSize;
 243   HRESULT hRet = S_OK;
 244
 245   TRACE("(%p,%p)\n", lpStream, lppList);
 246
 247   if(*lppList)
 248   {
 249     /* Free any existing list */
 250     LocalFree((HLOCAL)*lppList);
 251     *lppList = NULL;
 252   }
 253
 254   do
 255   {
 256     /* Read the size of the next item */
 257     hRet = IStream_Read(lpStream, &ulSize,sizeof(ulSize),&ulRead);
 258
 259     if(FAILED(hRet) || ulRead != sizeof(ulSize) || !ulSize)
 260       break; /* Read failed or read zero size (the end of the list) */
 261
 262     if(ulSize > 0xFFFF)
 263     {
 264       LARGE_INTEGER liZero;
 265       ULARGE_INTEGER ulPos;
 266
 267       liZero.QuadPart = 0;
 268
 269       /* Back the stream up; this object is too big for the list */
 270       if(SUCCEEDED(IStream_Seek(lpStream, liZero, STREAM_SEEK_CUR, &ulPos)))
 271       {
 272         liZero.QuadPart = ulPos.QuadPart - sizeof(ULONG);
 273         IStream_Seek(lpStream, liZero, STREAM_SEEK_SET, NULL);
 274       }
 275       break;
 276     }
 277     else if (ulSize >= sizeof(DATABLOCK_HEADER))
 278     {
 279       /* Add this new item to the list */
 280       if(ulSize > ulBuffSize)
 281       {
 282         /* We need more buffer space, allocate it */
 283         LPDATABLOCK_HEADER lpTemp;
 284
 285         if (pItem == bBuff)
 286           lpTemp = (LPDATABLOCK_HEADER)LocalAlloc(LMEM_ZEROINIT, ulSize);
 287         else
 288           lpTemp = (LPDATABLOCK_HEADER)LocalReAlloc((HLOCAL)pItem, ulSize,
 289                                                  LMEM_ZEROINIT|LMEM_MOVEABLE);
 290
 291         if(!lpTemp)
 292         {
 293           hRet = E_OUTOFMEMORY;
 294           break;
 295         }
 296         ulBuffSize = ulSize;
 297         pItem = lpTemp;
 298       }
 299
 300       pItem->cbSize = ulSize;
 301       ulSize -= sizeof(pItem->cbSize); /* already read this member */
 302
 303       /* Read the item Id and data */
 304       hRet = IStream_Read(lpStream, &pItem->dwSignature, ulSize, &ulRead);
 305
 306       if(FAILED(hRet) || ulRead != ulSize)
 307         break;
 308
 309       SHAddDataBlock(lppList, pItem); /* Insert Item */
 310     }
 311   } while(1);
 312
 313   /* If we allocated space, free it */
 314   if(pItem != bBuff)
 315     LocalFree((HLOCAL)pItem);
 316
 317   return hRet;
 318 }
 319
 320 /*************************************************************************
 321  *      @       [SHLWAPI.19]
 322  *
 323  * Free a DataBlock list.
 324  *
 325  * PARAMS
 326  *  lpList [I] List to free
 327  *
 328  * RETURNS
 329  *  Nothing.
 330  *
 331  * NOTES
 332  *  See SHWriteDataBlockList.
 333  */
 334 VOID WINAPI SHFreeDataBlockList(LPDBLIST lpList)
 335 {
 336   TRACE("(%p)\n", lpList);
 337
 338   if (lpList)
 339     LocalFree((HLOCAL)lpList);
 340 }
 341
 342 /*************************************************************************
 343  *      @       [SHLWAPI.21]
 344  *
 345  * Remove an item from a DataBlock list.
 346  *
 347  * PARAMS
 348  *  lppList     [O] List to remove the item from
 349  *  dwSignature [I] Id of item to remove
 350  *
 351  * RETURNS
 352  *  Success: TRUE.
 353  *  Failure: FALSE, If any parameters are invalid, or the item was not found.
 354  *
 355  * NOTES
 356  *  See SHWriteDataBlockList.
 357  */
 358 BOOL WINAPI SHRemoveDataBlock(LPDBLIST* lppList, DWORD dwSignature)
 359 {
 360   LPDATABLOCK_HEADER lpList = 0;
 361   LPDATABLOCK_HEADER lpItem = NULL;
 362   LPDATABLOCK_HEADER lpNext;
 363   ULONG ulNewSize;
 364
 365   TRACE("(%p,%d)\n", lppList, dwSignature);
 366
 367   if(lppList && (lpList = *lppList))
 368   {
 369     /* Search for item in list */
 370     while (lpList->cbSize)
 371     {
 372       if(lpList->dwSignature == dwSignature ||
 373         (lpList->dwSignature == CLIST_ID_CONTAINER && lpList[1].dwSignature == dwSignature))
 374       {
 375         lpItem = lpList; /* Found */
 376         break;
 377       }
 378       lpList = NextItem(lpList);
 379     }
 380   }
 381
 382   if(!lpItem)
 383     return FALSE;
 384
 385   lpList = lpNext = NextItem(lpItem);
 386
 387   /* Locate the end of the list */
 388   while (lpList->cbSize)
 389     lpList = NextItem(lpList);
 390
 391   /* Resize the list */
 392   ulNewSize = LocalSize((HLOCAL)*lppList) - lpItem->cbSize;
 393
 394   /* Copy following elements over lpItem */
 395   memmove(lpItem, lpNext, (char *)lpList - (char *)lpNext + sizeof(ULONG));
 396
 397   if(ulNewSize <= sizeof(ULONG))
 398   {
 399     LocalFree((HLOCAL)*lppList);
 400     *lppList = NULL; /* Removed the last element */
 401   }
 402   else
 403   {
 404     lpList = (LPDATABLOCK_HEADER)LocalReAlloc((HLOCAL)*lppList, ulNewSize,
 405                                            LMEM_ZEROINIT|LMEM_MOVEABLE);
 406     if(lpList)
 407       *lppList = lpList;
 408   }
 409   return TRUE;
 410 }
 411
 412 /*************************************************************************
 413  *      @       [SHLWAPI.22]
 414  *
 415  * Find an item in a DataBlock list.
 416  *
 417  * PARAMS
 418  *  lpList      [I] List to search
 419  *  dwSignature [I] Id of item to find
 420  *
 421  * RETURNS
 422  *  Success: A pointer to the list item found
 423  *  Failure: NULL
 424  *
 425  * NOTES
 426  *  See SHWriteDataBlockList.
 427  */
 428 DATABLOCK_HEADER* WINAPI SHFindDataBlock(LPDBLIST lpList, DWORD dwSignature)
 429 {
 430   TRACE("(%p,%d)\n", lpList, dwSignature);
 431
 432   if(lpList)
 433   {
 434     while(lpList->cbSize)
 435     {
 436       if(lpList->dwSignature == dwSignature)
 437         return lpList; /* Matched */
 438       else if(lpList->dwSignature == CLIST_ID_CONTAINER && lpList[1].dwSignature == dwSignature)
 439         return lpList + 1; /* Contained item matches */
 440
 441       lpList = NextItem(lpList);
 442     }
 443   }
 444   return NULL;
 445 }