source: trunk/src/ole32/old/memlockbytes.cpp@ 10080

Last change on this file since 10080 was 5601, checked in by sandervl, 25 years ago

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1/* $Id: memlockbytes.cpp,v 1.1 2001-04-26 19:26:11 sandervl Exp $ */
2/*
3 * Global memory implementation of ILockBytes.
4 *
5 * 21/9/99
6 *
7 * Copyright 1999 David J. Raison
8 *
9 * Direct port of Wine Implementation
10 * Copyright 1999 Thuy Nguyen
11 */
12
13#include "ole32.h"
14#include "debugtools.h"
15
16DEFAULT_DEBUG_CHANNEL(ole)
17
18/******************************************************************************
19 * HGLOBALLockBytesImpl definition.
20 *
21 * This class imlements the ILockBytes inteface and represents a byte array
22 * object supported by an HGLOBAL pointer.
23 */
24struct HGLOBALLockBytesImpl
25{
26 /*
27 * Needs to be the first item in the stuct
28 * since we want to cast this in an ILockBytes pointer
29 */
30 ICOM_VTABLE(ILockBytes) *lpvtbl;
31
32 /*
33 * Reference count
34 */
35 ULONG ref;
36
37 /*
38 * Support for the LockBytes object
39 */
40 HGLOBAL supportHandle;
41
42 /*
43 * This flag is TRUE if the HGLOBAL is destroyed when the object
44 * is finally released.
45 */
46 BOOL deleteOnRelease;
47
48 /*
49 * Helper variable that contains the size of the byte array
50 */
51 ULARGE_INTEGER byteArraySize;
52};
53
54typedef struct HGLOBALLockBytesImpl HGLOBALLockBytesImpl;
55
56/*
57 * Method definition for the HGLOBALLockBytesImpl class.
58 */
59HGLOBALLockBytesImpl* HGLOBALLockBytesImpl_Construct(
60 HGLOBAL hGlobal,
61 BOOL fDeleteOnRelease);
62
63void HGLOBALLockBytesImpl_Destroy(HGLOBALLockBytesImpl* This);
64
65HRESULT WINAPI HGLOBALLockBytesImpl_QueryInterface(
66 ILockBytes* iface,
67 REFIID riid, /* [in] */
68 void** ppvObject); /* [iid_is][out] */
69
70ULONG WINAPI HGLOBALLockBytesImpl_AddRef(
71 ILockBytes* iface);
72
73ULONG WINAPI HGLOBALLockBytesImpl_Release(
74 ILockBytes* iface);
75
76HRESULT WINAPI HGLOBALLockBytesImpl_ReadAt(
77 ILockBytes* iface,
78 ULARGE_INTEGER ulOffset, /* [in] */
79 void* pv, /* [length_is][size_is][out] */
80 ULONG cb, /* [in] */
81 ULONG* pcbRead); /* [out] */
82
83HRESULT WINAPI HGLOBALLockBytesImpl_WriteAt(
84 ILockBytes* iface,
85 ULARGE_INTEGER ulOffset, /* [in] */
86 const void* pv, /* [size_is][in] */
87 ULONG cb, /* [in] */
88 ULONG* pcbWritten); /* [out] */
89
90HRESULT WINAPI HGLOBALLockBytesImpl_Flush(
91 ILockBytes* iface);
92
93HRESULT WINAPI HGLOBALLockBytesImpl_SetSize(
94 ILockBytes* iface,
95 ULARGE_INTEGER libNewSize); /* [in] */
96
97HRESULT WINAPI HGLOBALLockBytesImpl_LockRegion(
98 ILockBytes* iface,
99 ULARGE_INTEGER libOffset, /* [in] */
100 ULARGE_INTEGER cb, /* [in] */
101 DWORD dwLockType); /* [in] */
102
103HRESULT WINAPI HGLOBALLockBytesImpl_UnlockRegion(
104 ILockBytes* iface,
105 ULARGE_INTEGER libOffset, /* [in] */
106 ULARGE_INTEGER cb, /* [in] */
107 DWORD dwLockType); /* [in] */
108
109HRESULT WINAPI HGLOBALLockBytesImpl_Stat(
110 ILockBytes* iface,
111 STATSTG* pstatstg, /* [out] */
112 DWORD grfStatFlag); /* [in] */
113
114/*
115 * Virtual function table for the HGLOBALLockBytesImpl class.
116 */
117static ICOM_VTABLE(ILockBytes) HGLOBALLockBytesImpl_Vtbl =
118{
119 ICOM_MSVTABLE_COMPAT_DummyRTTIVALUE
120 HGLOBALLockBytesImpl_QueryInterface,
121 HGLOBALLockBytesImpl_AddRef,
122 HGLOBALLockBytesImpl_Release,
123 HGLOBALLockBytesImpl_ReadAt,
124 HGLOBALLockBytesImpl_WriteAt,
125 HGLOBALLockBytesImpl_Flush,
126 HGLOBALLockBytesImpl_SetSize,
127 HGLOBALLockBytesImpl_LockRegion,
128 HGLOBALLockBytesImpl_UnlockRegion,
129 HGLOBALLockBytesImpl_Stat,
130};
131
132/******************************************************************************
133 * CreateILockBytesOnHGlobal [OLE32.57]
134 */
135HRESULT WINAPI CreateILockBytesOnHGlobal(HGLOBAL hGlobal,
136 BOOL fDeleteOnRelease,
137 LPLOCKBYTES* ppLkbyt)
138{
139 HGLOBALLockBytesImpl* newLockBytes;
140
141 newLockBytes = HGLOBALLockBytesImpl_Construct(hGlobal, fDeleteOnRelease);
142
143 if (newLockBytes != NULL)
144 {
145 return IUnknown_QueryInterface((IUnknown*)newLockBytes,
146 &IID_ILockBytes,
147 (void**)ppLkbyt);
148 }
149
150 return E_OUTOFMEMORY;
151}
152
153/******************************************************************************
154 * GetHGlobalFromILockBytes [OLE32.70]
155 */
156HRESULT WINAPI GetHGlobalFromILockBytes(ILockBytes* plkbyt, HGLOBAL* phglobal)
157{
158 HGLOBALLockBytesImpl* const pMemLockBytes = (HGLOBALLockBytesImpl*)plkbyt;
159
160 if (pMemLockBytes->lpvtbl == &HGLOBALLockBytesImpl_Vtbl)
161 *phglobal = pMemLockBytes->supportHandle;
162 else
163 *phglobal = 0;
164
165 if (*phglobal == 0)
166 return E_INVALIDARG;
167
168 return S_OK;
169}
170
171/******************************************************************************
172 *
173 * HGLOBALLockBytesImpl implementation
174 *
175 */
176
177/******************************************************************************
178 * This is the constructor for the HGLOBALLockBytesImpl class.
179 *
180 * Params:
181 * hGlobal - Handle that will support the stream. can be NULL.
182 * fDeleteOnRelease - Flag set to TRUE if the HGLOBAL will be released
183 * when the IStream object is destroyed.
184 */
185HGLOBALLockBytesImpl* HGLOBALLockBytesImpl_Construct(HGLOBAL hGlobal,
186 BOOL fDeleteOnRelease)
187{
188 HGLOBALLockBytesImpl* newLockBytes;
189 newLockBytes = (HGLOBALLockBytesImpl*)HeapAlloc(GetProcessHeap(), 0, sizeof(HGLOBALLockBytesImpl));
190
191 if (newLockBytes!=0)
192 {
193 /*
194 * Set up the virtual function table and reference count.
195 */
196 newLockBytes->lpvtbl = &HGLOBALLockBytesImpl_Vtbl;
197 newLockBytes->ref = 0;
198
199 /*
200 * Initialize the support.
201 */
202 newLockBytes->supportHandle = hGlobal;
203 newLockBytes->deleteOnRelease = fDeleteOnRelease;
204
205 /*
206 * This method will allocate a handle if one is not supplied.
207 */
208 if (newLockBytes->supportHandle == 0)
209 {
210 newLockBytes->supportHandle = GlobalAlloc(GMEM_MOVEABLE |
211 GMEM_NODISCARD,
212 0);
213 }
214
215 /*
216 * Initialize the size of the array to the size of the handle.
217 */
218 newLockBytes->byteArraySize.HighPart = 0;
219 newLockBytes->byteArraySize.LowPart = GlobalSize(
220 newLockBytes->supportHandle);
221 }
222
223 return newLockBytes;
224}
225
226/******************************************************************************
227 * This is the destructor of the HGLOBALStreamImpl class.
228 *
229 * This method will clean-up all the resources used-up by the given
230 * HGLOBALLockBytesImpl class. The pointer passed-in to this function will be
231 * freed and will not be valid anymore.
232 */
233void HGLOBALLockBytesImpl_Destroy(HGLOBALLockBytesImpl* This)
234{
235 /*
236 * Release the HGlobal if the constructor asked for that.
237 */
238 if (This->deleteOnRelease)
239 {
240 GlobalFree(This->supportHandle);
241 This->supportHandle = 0;
242 }
243
244 /*
245 * Finally, free the memory used-up by the class.
246 */
247 HeapFree(GetProcessHeap(), 0, This);
248}
249
250/******************************************************************************
251 * This implements the IUnknown method QueryInterface for this
252 * class
253 */
254HRESULT WINAPI HGLOBALLockBytesImpl_QueryInterface(
255 ILockBytes* iface,
256 REFIID riid, /* [in] */
257 void** ppvObject) /* [iid_is][out] */
258{
259 HGLOBALLockBytesImpl* const This=(HGLOBALLockBytesImpl*)iface;
260
261 /*
262 * Perform a sanity check on the parameters.
263 */
264 if (ppvObject==0)
265 return E_INVALIDARG;
266
267 /*
268 * Initialize the return parameter.
269 */
270 *ppvObject = 0;
271
272 /*
273 * Compare the riid with the interface IDs implemented by this object.
274 */
275 if (memcmp(&IID_IUnknown, riid, sizeof(IID_IUnknown)) == 0)
276 {
277 *ppvObject = (ILockBytes*)This;
278 }
279 else if (memcmp(&IID_ILockBytes, riid, sizeof(IID_ILockBytes)) == 0)
280 {
281 *ppvObject = (ILockBytes*)This;
282 }
283
284 /*
285 * Check that we obtained an interface.
286 */
287 if ((*ppvObject)==0)
288 return E_NOINTERFACE;
289
290 /*
291 * Query Interface always increases the reference count by one when it is
292 * successful
293 */
294 HGLOBALLockBytesImpl_AddRef(iface);
295
296 return S_OK;;
297}
298
299/******************************************************************************
300 * This implements the IUnknown method AddRef for this
301 * class
302 */
303ULONG WINAPI HGLOBALLockBytesImpl_AddRef(ILockBytes* iface)
304{
305 HGLOBALLockBytesImpl* const This=(HGLOBALLockBytesImpl*)iface;
306
307 This->ref++;
308
309 return This->ref;
310}
311
312/******************************************************************************
313 * This implements the IUnknown method Release for this
314 * class
315 */
316ULONG WINAPI HGLOBALLockBytesImpl_Release(ILockBytes* iface)
317{
318 HGLOBALLockBytesImpl* const This=(HGLOBALLockBytesImpl*)iface;
319
320 ULONG newRef;
321
322 This->ref--;
323
324 newRef = This->ref;
325
326 /*
327 * If the reference count goes down to 0, perform suicide.
328 */
329 if (newRef==0)
330 {
331 HGLOBALLockBytesImpl_Destroy(This);
332 }
333
334 return newRef;
335}
336
337/******************************************************************************
338 * This method is part of the ILockBytes interface.
339 *
340 * It reads a block of information from the byte array at the specified
341 * offset.
342 *
343 * See the documentation of ILockBytes for more info.
344 */
345HRESULT WINAPI HGLOBALLockBytesImpl_ReadAt(
346 ILockBytes* iface,
347 ULARGE_INTEGER ulOffset, /* [in] */
348 void* pv, /* [length_is][size_is][out] */
349 ULONG cb, /* [in] */
350 ULONG* pcbRead) /* [out] */
351{
352 HGLOBALLockBytesImpl* const This=(HGLOBALLockBytesImpl*)iface;
353
354 void* supportBuffer;
355 ULONG bytesReadBuffer = 0;
356 ULONG bytesToReadFromBuffer;
357
358 /*
359 * If the caller is not interested in the number of bytes read,
360 * we use another buffer to avoid "if" statements in the code.
361 */
362 if (pcbRead == 0)
363 pcbRead = &bytesReadBuffer;
364
365 /*
366 * Make sure the offset is valid.
367 */
368 if (ulOffset.LowPart > This->byteArraySize.LowPart)
369 return E_FAIL;
370
371 /*
372 * Using the known size of the array, calculate the number of bytes
373 * to read.
374 */
375 bytesToReadFromBuffer = MIN(This->byteArraySize.LowPart -
376 ulOffset.LowPart, cb);
377
378 /*
379 * Lock the buffer in position and copy the data.
380 */
381 supportBuffer = GlobalLock(This->supportHandle);
382
383 memcpy(pv,
384 (char *) supportBuffer + ulOffset.LowPart,
385 bytesToReadFromBuffer);
386
387 /*
388 * Return the number of bytes read.
389 */
390 *pcbRead = bytesToReadFromBuffer;
391
392 /*
393 * Cleanup
394 */
395 GlobalUnlock(This->supportHandle);
396
397 /*
398 * The function returns S_OK if the specified number of bytes were read
399 * or the end of the array was reached.
400 * It returns STG_E_READFAULT if the number of bytes to read does not equal
401 * the number of bytes actually read.
402 */
403 if(*pcbRead == cb)
404 return S_OK;
405
406 return STG_E_READFAULT;
407}
408
409/******************************************************************************
410 * This method is part of the ILockBytes interface.
411 *
412 * It writes the specified bytes at the specified offset.
413 * position. If the array is too small, it will be resized.
414 *
415 * See the documentation of ILockBytes for more info.
416 */
417HRESULT WINAPI HGLOBALLockBytesImpl_WriteAt(
418 ILockBytes* iface,
419 ULARGE_INTEGER ulOffset, /* [in] */
420 const void* pv, /* [size_is][in] */
421 ULONG cb, /* [in] */
422 ULONG* pcbWritten) /* [out] */
423{
424 HGLOBALLockBytesImpl* const This=(HGLOBALLockBytesImpl*)iface;
425
426 void* supportBuffer;
427 ULARGE_INTEGER newSize;
428 ULONG bytesWritten = 0;
429
430 /*
431 * If the caller is not interested in the number of bytes written,
432 * we use another buffer to avoid "if" statements in the code.
433 */
434 if (pcbWritten == 0)
435 pcbWritten = &bytesWritten;
436
437 if (cb == 0)
438 {
439 return S_OK;
440 }
441 else
442 {
443 newSize.HighPart = 0;
444 newSize.LowPart = ulOffset.LowPart + cb;
445 }
446
447 /*
448 * Verify if we need to grow the stream
449 */
450 if (newSize.LowPart > This->byteArraySize.LowPart)
451 {
452 /* grow stream */
453 if (HGLOBALLockBytesImpl_SetSize(iface, newSize) == STG_E_MEDIUMFULL)
454 return STG_E_MEDIUMFULL;
455 }
456
457 /*
458 * Lock the buffer in position and copy the data.
459 */
460 supportBuffer = GlobalLock(This->supportHandle);
461
462 memcpy((char *) supportBuffer + ulOffset.LowPart, pv, cb);
463
464 /*
465 * Return the number of bytes written.
466 */
467 *pcbWritten = cb;
468
469 /*
470 * Cleanup
471 */
472 GlobalUnlock(This->supportHandle);
473
474 return S_OK;
475}
476
477/******************************************************************************
478 * This method is part of the ILockBytes interface.
479 *
480 * See the documentation of ILockBytes for more info.
481 */
482HRESULT WINAPI HGLOBALLockBytesImpl_Flush(ILockBytes* iface)
483{
484 return S_OK;
485}
486
487/******************************************************************************
488 * This method is part of the ILockBytes interface.
489 *
490 * It will change the size of the byte array.
491 *
492 * See the documentation of ILockBytes for more info.
493 */
494HRESULT WINAPI HGLOBALLockBytesImpl_SetSize(
495 ILockBytes* iface,
496 ULARGE_INTEGER libNewSize) /* [in] */
497{
498 HGLOBALLockBytesImpl* const This=(HGLOBALLockBytesImpl*)iface;
499
500 /*
501 * As documented.
502 */
503 if (libNewSize.HighPart != 0)
504 return STG_E_INVALIDFUNCTION;
505
506 if (This->byteArraySize.LowPart == libNewSize.LowPart)
507 return S_OK;
508
509 /*
510 * Re allocate the HGlobal to fit the new size of the stream.
511 */
512 This->supportHandle = GlobalReAlloc(This->supportHandle,
513 libNewSize.LowPart,
514 0);
515
516 if (This->supportHandle == 0)
517 return STG_E_MEDIUMFULL;
518
519 This->byteArraySize.LowPart = libNewSize.LowPart;
520
521 return S_OK;
522}
523
524/******************************************************************************
525 * This method is part of the ILockBytes interface.
526 *
527 * The global memory implementation of ILockBytes does not support locking.
528 *
529 * See the documentation of ILockBytes for more info.
530 */
531HRESULT WINAPI HGLOBALLockBytesImpl_LockRegion(
532 ILockBytes* iface,
533 ULARGE_INTEGER libOffset, /* [in] */
534 ULARGE_INTEGER cb, /* [in] */
535 DWORD dwLockType) /* [in] */
536{
537 return STG_E_INVALIDFUNCTION;
538}
539
540/******************************************************************************
541 * This method is part of the ILockBytes interface.
542 *
543 * The global memory implementation of ILockBytes does not support locking.
544 *
545 * See the documentation of ILockBytes for more info.
546 */
547HRESULT WINAPI HGLOBALLockBytesImpl_UnlockRegion(
548 ILockBytes* iface,
549 ULARGE_INTEGER libOffset, /* [in] */
550 ULARGE_INTEGER cb, /* [in] */
551 DWORD dwLockType) /* [in] */
552{
553 return STG_E_INVALIDFUNCTION;
554}
555
556/******************************************************************************
557 * This method is part of the ILockBytes interface.
558 *
559 * This method returns information about the current
560 * byte array object.
561 *
562 * See the documentation of ILockBytes for more info.
563 */
564HRESULT WINAPI HGLOBALLockBytesImpl_Stat(
565 ILockBytes* iface,
566 STATSTG* pstatstg, /* [out] */
567 DWORD grfStatFlag) /* [in] */
568{
569 HGLOBALLockBytesImpl* const This=(HGLOBALLockBytesImpl*)iface;
570
571 memset(pstatstg, 0, sizeof(STATSTG));
572
573 pstatstg->pwcsName = NULL;
574 pstatstg->type = STGTY_LOCKBYTES;
575 pstatstg->cbSize = This->byteArraySize;
576
577 return S_OK;
578}
579
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