1 /*
2 ******************************************************************************
3 *
4 * Copyright (C) 1997-2011, International Business Machines
5 * Corporation and others. All Rights Reserved.
6 *
7 ******************************************************************************
8 *
9 * File CMEMORY.H
10 *
11 * Contains stdlib.h/string.h memory functions
12 *
13 * @author Bertrand A. Damiba
14 *
15 * Modification History:
16 *
17 * Date Name Description
18 * 6/20/98 Bertrand Created.
19 * 05/03/99 stephen Changed from functions to macros.
20 *
21 ******************************************************************************
22 */
23
24 #ifndef CMEMORY_H
25 #define CMEMORY_H
26
27 #include <stddef.h>
28 #include <string.h>
29 #include "unicode/utypes.h"
30 #include "unicode/localpointer.h"
31
32 #define uprv_memcpy(dst, src, size) U_STANDARD_CPP_NAMESPACE memcpy(dst, src, size)
33 #define uprv_memmove(dst, src, size) U_STANDARD_CPP_NAMESPACE memmove(dst, src, size)
34 #define uprv_memset(buffer, mark, size) U_STANDARD_CPP_NAMESPACE memset(buffer, mark, size)
35 #define uprv_memcmp(buffer1, buffer2, size) U_STANDARD_CPP_NAMESPACE memcmp(buffer1, buffer2,size)
36
37 U_CAPI void * U_EXPORT2
38 uprv_malloc(size_t s);
39
40 U_CAPI void * U_EXPORT2
41 uprv_realloc(void *mem, size_t size);
42
43 U_CAPI void U_EXPORT2
44 uprv_free(void *mem);
45
46 /**
47 * This should align the memory properly on any machine.
48 * This is very useful for the safeClone functions.
49 */
50 typedef union {
51 long t1;
52 double t2;
53 void *t3;
54 } UAlignedMemory;
55
56 /**
57 * Get the least significant bits of a pointer (a memory address).
58 * For example, with a mask of 3, the macro gets the 2 least significant bits,
59 * which will be 0 if the pointer is 32-bit (4-byte) aligned.
60 *
61 * ptrdiff_t is the most appropriate integer type to cast to.
62 * size_t should work too, since on most (or all?) platforms it has the same
63 * width as ptrdiff_t.
64 */
65 #define U_POINTER_MASK_LSB(ptr, mask) (((ptrdiff_t)(char *)(ptr)) & (mask))
66
67 /**
68 * Get the amount of bytes that a pointer is off by from
69 * the previous UAlignedMemory-aligned pointer.
70 */
71 #define U_ALIGNMENT_OFFSET(ptr) U_POINTER_MASK_LSB(ptr, sizeof(UAlignedMemory) - 1)
72
73 /**
74 * Get the amount of bytes to add to a pointer
75 * in order to get the next UAlignedMemory-aligned address.
76 */
77 #define U_ALIGNMENT_OFFSET_UP(ptr) (sizeof(UAlignedMemory) - U_ALIGNMENT_OFFSET(ptr))
78
79 /**
80 * Indicate whether the ICU allocation functions have been used.
81 * This is used to determine whether ICU is in an initial, unused state.
82 */
83 U_CFUNC UBool
84 cmemory_inUse(void);
85
86 /**
87 * Heap clean up function, called from u_cleanup()
88 * Clears any user heap functions from u_setMemoryFunctions()
89 * Does NOT deallocate any remaining allocated memory.
90 */
91 U_CFUNC UBool
92 cmemory_cleanup(void);
93
94 #ifdef XP_CPLUSPLUS
95
96 U_NAMESPACE_BEGIN
97
98 /**
99 * "Smart pointer" class, deletes memory via uprv_free().
100 * For most methods see the LocalPointerBase base class.
101 * Adds operator[] for array item access.
102 *
103 * @see LocalPointerBase
104 */
105 template<typename T>
106 class LocalMemory : public LocalPointerBase<T> {
107 public:
108 /**
109 * Constructor takes ownership.
110 * @param p simple pointer to an array of T items that is adopted
111 */
112 explicit LocalMemory(T *p=NULL) : LocalPointerBase<T>(p) {}
113 /**
114 * Destructor deletes the memory it owns.
115 */
~LocalMemory()116 ~LocalMemory() {
117 uprv_free(LocalPointerBase<T>::ptr);
118 }
119 /**
120 * Deletes the array it owns,
121 * and adopts (takes ownership of) the one passed in.
122 * @param p simple pointer to an array of T items that is adopted
123 */
adoptInstead(T * p)124 void adoptInstead(T *p) {
125 uprv_free(LocalPointerBase<T>::ptr);
126 LocalPointerBase<T>::ptr=p;
127 }
128 /**
129 * Deletes the array it owns, allocates a new one and reset its bytes to 0.
130 * Returns the new array pointer.
131 * If the allocation fails, then the current array is unchanged and
132 * this method returns NULL.
133 * @param newCapacity must be >0
134 * @return the allocated array pointer, or NULL if the allocation failed
135 */
136 inline T *allocateInsteadAndReset(int32_t newCapacity=1);
137 /**
138 * Deletes the array it owns and allocates a new one, copying length T items.
139 * Returns the new array pointer.
140 * If the allocation fails, then the current array is unchanged and
141 * this method returns NULL.
142 * @param newCapacity must be >0
143 * @param length number of T items to be copied from the old array to the new one;
144 * must be no more than the capacity of the old array,
145 * which the caller must track because the LocalMemory does not track it
146 * @return the allocated array pointer, or NULL if the allocation failed
147 */
148 inline T *allocateInsteadAndCopy(int32_t newCapacity=1, int32_t length=0);
149 /**
150 * Array item access (writable).
151 * No index bounds check.
152 * @param i array index
153 * @return reference to the array item
154 */
155 T &operator[](ptrdiff_t i) const { return LocalPointerBase<T>::ptr[i]; }
156 };
157
158 template<typename T>
allocateInsteadAndReset(int32_t newCapacity)159 inline T *LocalMemory<T>::allocateInsteadAndReset(int32_t newCapacity) {
160 if(newCapacity>0) {
161 T *p=(T *)uprv_malloc(newCapacity*sizeof(T));
162 if(p!=NULL) {
163 uprv_memset(p, 0, newCapacity*sizeof(T));
164 uprv_free(LocalPointerBase<T>::ptr);
165 LocalPointerBase<T>::ptr=p;
166 }
167 return p;
168 } else {
169 return NULL;
170 }
171 }
172
173
174 template<typename T>
allocateInsteadAndCopy(int32_t newCapacity,int32_t length)175 inline T *LocalMemory<T>::allocateInsteadAndCopy(int32_t newCapacity, int32_t length) {
176 if(newCapacity>0) {
177 T *p=(T *)uprv_malloc(newCapacity*sizeof(T));
178 if(p!=NULL) {
179 if(length>0) {
180 if(length>newCapacity) {
181 length=newCapacity;
182 }
183 uprv_memcpy(p, LocalPointerBase<T>::ptr, length*sizeof(T));
184 }
185 uprv_free(LocalPointerBase<T>::ptr);
186 LocalPointerBase<T>::ptr=p;
187 }
188 return p;
189 } else {
190 return NULL;
191 }
192 }
193
194 /**
195 * Simple array/buffer management class using uprv_malloc() and uprv_free().
196 * Provides an internal array with fixed capacity. Can alias another array
197 * or allocate one.
198 *
199 * The array address is properly aligned for type T. It might not be properly
200 * aligned for types larger than T (or larger than the largest subtype of T).
201 *
202 * Unlike LocalMemory and LocalArray, this class never adopts
203 * (takes ownership of) another array.
204 */
205 template<typename T, int32_t stackCapacity>
206 class MaybeStackArray {
207 public:
208 /**
209 * Default constructor initializes with internal T[stackCapacity] buffer.
210 */
MaybeStackArray()211 MaybeStackArray() : ptr(stackArray), capacity(stackCapacity), needToRelease(FALSE) {}
212 /**
213 * Destructor deletes the array (if owned).
214 */
~MaybeStackArray()215 ~MaybeStackArray() { releaseArray(); }
216 /**
217 * Returns the array capacity (number of T items).
218 * @return array capacity
219 */
getCapacity()220 int32_t getCapacity() const { return capacity; }
221 /**
222 * Access without ownership change.
223 * @return the array pointer
224 */
getAlias()225 T *getAlias() const { return ptr; }
226 /**
227 * Returns the array limit. Simple convenience method.
228 * @return getAlias()+getCapacity()
229 */
getArrayLimit()230 T *getArrayLimit() const { return getAlias()+capacity; }
231 /**
232 * Access without ownership change. Same as getAlias().
233 * A class instance can be used directly in expressions that take a T *.
234 * @return the array pointer
235 */
236 operator T *() const { return ptr; }
237 /**
238 * Array item access (writable).
239 * No index bounds check.
240 * @param i array index
241 * @return reference to the array item
242 */
243 T &operator[](ptrdiff_t i) { return ptr[i]; }
244 /**
245 * Deletes the array (if owned) and aliases another one, no transfer of ownership.
246 * If the arguments are illegal, then the current array is unchanged.
247 * @param otherArray must not be NULL
248 * @param otherCapacity must be >0
249 */
aliasInstead(T * otherArray,int32_t otherCapacity)250 void aliasInstead(T *otherArray, int32_t otherCapacity) {
251 if(otherArray!=NULL && otherCapacity>0) {
252 releaseArray();
253 ptr=otherArray;
254 capacity=otherCapacity;
255 needToRelease=FALSE;
256 }
257 }
258 /**
259 * Deletes the array (if owned) and allocates a new one, copying length T items.
260 * Returns the new array pointer.
261 * If the allocation fails, then the current array is unchanged and
262 * this method returns NULL.
263 * @param newCapacity can be less than or greater than the current capacity;
264 * must be >0
265 * @param length number of T items to be copied from the old array to the new one
266 * @return the allocated array pointer, or NULL if the allocation failed
267 */
268 inline T *resize(int32_t newCapacity, int32_t length=0);
269 /**
270 * Gives up ownership of the array if owned, or else clones it,
271 * copying length T items; resets itself to the internal stack array.
272 * Returns NULL if the allocation failed.
273 * @param length number of T items to copy when cloning,
274 * and capacity of the clone when cloning
275 * @param resultCapacity will be set to the returned array's capacity (output-only)
276 * @return the array pointer;
277 * caller becomes responsible for deleting the array
278 */
279 inline T *orphanOrClone(int32_t length, int32_t &resultCapacity);
280 private:
281 T *ptr;
282 int32_t capacity;
283 UBool needToRelease;
284 T stackArray[stackCapacity];
releaseArray()285 void releaseArray() {
286 if(needToRelease) {
287 uprv_free(ptr);
288 }
289 }
290 /* No comparison operators with other MaybeStackArray's. */
291 bool operator==(const MaybeStackArray & /*other*/) {return FALSE;}
292 bool operator!=(const MaybeStackArray & /*other*/) {return TRUE;}
293 /* No ownership transfer: No copy constructor, no assignment operator. */
MaybeStackArray(const MaybeStackArray &)294 MaybeStackArray(const MaybeStackArray & /*other*/) {}
295 void operator=(const MaybeStackArray & /*other*/) {}
296
297 // No heap allocation. Use only on the stack.
298 // (Declaring these functions private triggers a cascade of problems:
299 // MSVC insists on exporting an instantiation of MaybeStackArray, which
300 // requires that all functions be defined.
301 // An empty implementation of new() is rejected, it must return a value.
302 // Returning NULL is rejected by gcc for operator new.
303 // The expedient thing is just not to override operator new.
304 // While relatively pointless, heap allocated instances will function.
305 // static void * U_EXPORT2 operator new(size_t size);
306 // static void * U_EXPORT2 operator new[](size_t size);
307 #if U_HAVE_PLACEMENT_NEW
308 // static void * U_EXPORT2 operator new(size_t, void *ptr);
309 #endif
310 };
311
312 template<typename T, int32_t stackCapacity>
resize(int32_t newCapacity,int32_t length)313 inline T *MaybeStackArray<T, stackCapacity>::resize(int32_t newCapacity, int32_t length) {
314 if(newCapacity>0) {
315 T *p=(T *)uprv_malloc(newCapacity*sizeof(T));
316 if(p!=NULL) {
317 if(length>0) {
318 if(length>capacity) {
319 length=capacity;
320 }
321 if(length>newCapacity) {
322 length=newCapacity;
323 }
324 uprv_memcpy(p, ptr, length*sizeof(T));
325 }
326 releaseArray();
327 ptr=p;
328 capacity=newCapacity;
329 needToRelease=TRUE;
330 }
331 return p;
332 } else {
333 return NULL;
334 }
335 }
336
337 template<typename T, int32_t stackCapacity>
orphanOrClone(int32_t length,int32_t & resultCapacity)338 inline T *MaybeStackArray<T, stackCapacity>::orphanOrClone(int32_t length, int32_t &resultCapacity) {
339 T *p;
340 if(needToRelease) {
341 p=ptr;
342 } else if(length<=0) {
343 return NULL;
344 } else {
345 if(length>capacity) {
346 length=capacity;
347 }
348 p=(T *)uprv_malloc(length*sizeof(T));
349 if(p==NULL) {
350 return NULL;
351 }
352 uprv_memcpy(p, ptr, length*sizeof(T));
353 }
354 resultCapacity=length;
355 ptr=stackArray;
356 capacity=stackCapacity;
357 needToRelease=FALSE;
358 return p;
359 }
360
361 /**
362 * Variant of MaybeStackArray that allocates a header struct and an array
363 * in one contiguous memory block, using uprv_malloc() and uprv_free().
364 * Provides internal memory with fixed array capacity. Can alias another memory
365 * block or allocate one.
366 * The stackCapacity is the number of T items in the internal memory,
367 * not counting the H header.
368 * Unlike LocalMemory and LocalArray, this class never adopts
369 * (takes ownership of) another memory block.
370 */
371 template<typename H, typename T, int32_t stackCapacity>
372 class MaybeStackHeaderAndArray {
373 public:
374 /**
375 * Default constructor initializes with internal H+T[stackCapacity] buffer.
376 */
MaybeStackHeaderAndArray()377 MaybeStackHeaderAndArray() : ptr(&stackHeader), capacity(stackCapacity), needToRelease(FALSE) {}
378 /**
379 * Destructor deletes the memory (if owned).
380 */
~MaybeStackHeaderAndArray()381 ~MaybeStackHeaderAndArray() { releaseMemory(); }
382 /**
383 * Returns the array capacity (number of T items).
384 * @return array capacity
385 */
getCapacity()386 int32_t getCapacity() const { return capacity; }
387 /**
388 * Access without ownership change.
389 * @return the header pointer
390 */
getAlias()391 H *getAlias() const { return ptr; }
392 /**
393 * Returns the array start.
394 * @return array start, same address as getAlias()+1
395 */
getArrayStart()396 T *getArrayStart() const { return reinterpret_cast<T *>(getAlias()+1); }
397 /**
398 * Returns the array limit.
399 * @return array limit
400 */
getArrayLimit()401 T *getArrayLimit() const { return getArrayStart()+capacity; }
402 /**
403 * Access without ownership change. Same as getAlias().
404 * A class instance can be used directly in expressions that take a T *.
405 * @return the header pointer
406 */
407 operator H *() const { return ptr; }
408 /**
409 * Array item access (writable).
410 * No index bounds check.
411 * @param i array index
412 * @return reference to the array item
413 */
414 T &operator[](ptrdiff_t i) { return getArrayStart()[i]; }
415 /**
416 * Deletes the memory block (if owned) and aliases another one, no transfer of ownership.
417 * If the arguments are illegal, then the current memory is unchanged.
418 * @param otherArray must not be NULL
419 * @param otherCapacity must be >0
420 */
aliasInstead(H * otherMemory,int32_t otherCapacity)421 void aliasInstead(H *otherMemory, int32_t otherCapacity) {
422 if(otherMemory!=NULL && otherCapacity>0) {
423 releaseMemory();
424 ptr=otherMemory;
425 capacity=otherCapacity;
426 needToRelease=FALSE;
427 }
428 }
429 /**
430 * Deletes the memory block (if owned) and allocates a new one,
431 * copying the header and length T array items.
432 * Returns the new header pointer.
433 * If the allocation fails, then the current memory is unchanged and
434 * this method returns NULL.
435 * @param newCapacity can be less than or greater than the current capacity;
436 * must be >0
437 * @param length number of T items to be copied from the old array to the new one
438 * @return the allocated pointer, or NULL if the allocation failed
439 */
440 inline H *resize(int32_t newCapacity, int32_t length=0);
441 /**
442 * Gives up ownership of the memory if owned, or else clones it,
443 * copying the header and length T array items; resets itself to the internal memory.
444 * Returns NULL if the allocation failed.
445 * @param length number of T items to copy when cloning,
446 * and array capacity of the clone when cloning
447 * @param resultCapacity will be set to the returned array's capacity (output-only)
448 * @return the header pointer;
449 * caller becomes responsible for deleting the array
450 */
451 inline H *orphanOrClone(int32_t length, int32_t &resultCapacity);
452 private:
453 H *ptr;
454 int32_t capacity;
455 UBool needToRelease;
456 // stackHeader must precede stackArray immediately.
457 H stackHeader;
458 T stackArray[stackCapacity];
releaseMemory()459 void releaseMemory() {
460 if(needToRelease) {
461 uprv_free(ptr);
462 }
463 }
464 /* No comparison operators with other MaybeStackHeaderAndArray's. */
465 bool operator==(const MaybeStackHeaderAndArray & /*other*/) {return FALSE;}
466 bool operator!=(const MaybeStackHeaderAndArray & /*other*/) {return TRUE;}
467 /* No ownership transfer: No copy constructor, no assignment operator. */
MaybeStackHeaderAndArray(const MaybeStackHeaderAndArray &)468 MaybeStackHeaderAndArray(const MaybeStackHeaderAndArray & /*other*/) {}
469 void operator=(const MaybeStackHeaderAndArray & /*other*/) {}
470
471 // No heap allocation. Use only on the stack.
472 // (Declaring these functions private triggers a cascade of problems;
473 // see the MaybeStackArray class for details.)
474 // static void * U_EXPORT2 operator new(size_t size);
475 // static void * U_EXPORT2 operator new[](size_t size);
476 #if U_HAVE_PLACEMENT_NEW
477 // static void * U_EXPORT2 operator new(size_t, void *ptr);
478 #endif
479 };
480
481 template<typename H, typename T, int32_t stackCapacity>
resize(int32_t newCapacity,int32_t length)482 inline H *MaybeStackHeaderAndArray<H, T, stackCapacity>::resize(int32_t newCapacity,
483 int32_t length) {
484 if(newCapacity>=0) {
485 H *p=(H *)uprv_malloc(sizeof(H)+newCapacity*sizeof(T));
486 if(p!=NULL) {
487 if(length<0) {
488 length=0;
489 } else if(length>0) {
490 if(length>capacity) {
491 length=capacity;
492 }
493 if(length>newCapacity) {
494 length=newCapacity;
495 }
496 }
497 uprv_memcpy(p, ptr, sizeof(H)+length*sizeof(T));
498 releaseMemory();
499 ptr=p;
500 capacity=newCapacity;
501 needToRelease=TRUE;
502 }
503 return p;
504 } else {
505 return NULL;
506 }
507 }
508
509 template<typename H, typename T, int32_t stackCapacity>
orphanOrClone(int32_t length,int32_t & resultCapacity)510 inline H *MaybeStackHeaderAndArray<H, T, stackCapacity>::orphanOrClone(int32_t length,
511 int32_t &resultCapacity) {
512 H *p;
513 if(needToRelease) {
514 p=ptr;
515 } else {
516 if(length<0) {
517 length=0;
518 } else if(length>capacity) {
519 length=capacity;
520 }
521 p=(H *)uprv_malloc(sizeof(H)+length*sizeof(T));
522 if(p==NULL) {
523 return NULL;
524 }
525 uprv_memcpy(p, ptr, sizeof(H)+length*sizeof(T));
526 }
527 resultCapacity=length;
528 ptr=&stackHeader;
529 capacity=stackCapacity;
530 needToRelease=FALSE;
531 return p;
532 }
533
534 U_NAMESPACE_END
535
536 #endif /* XP_CPLUSPLUS */
537 #endif /* CMEMORY_H */
538