xref: /xnu-11215/libkern/c++/OSData.cpp (revision 855239e5)
1 /*
2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
3  *
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6  * This file contains Original Code and/or Modifications of Original Code
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8  * Version 2.0 (the 'License'). You may not use this file except in
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10  * may not be used to create, or enable the creation or redistribution of,
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12  * circumvent, violate, or enable the circumvention or violation of, any
13  * terms of an Apple operating system software license agreement.
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15  * Please obtain a copy of the License at
16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
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18  * The Original Code and all software distributed under the License are
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20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
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27  */
28 /* IOData.m created by rsulack on Thu 25-Sep-1997 */
29 
30 #include <string.h>
31 
32 #include <libkern/c++/OSData.h>
33 #include <libkern/c++/OSSerialize.h>
34 #include <libkern/c++/OSLib.h>
35 #include <libkern/c++/OSString.h>
36 #include <string.h>
37 
38 #define super OSObject
39 
40 OSDefineMetaClassAndStructors(OSData, OSObject)
41 OSMetaClassDefineReservedUsed(OSData, 0);    // setDeallocFunction
42 OSMetaClassDefineReservedUnused(OSData, 1);
43 OSMetaClassDefineReservedUnused(OSData, 2);
44 OSMetaClassDefineReservedUnused(OSData, 3);
45 OSMetaClassDefineReservedUnused(OSData, 4);
46 OSMetaClassDefineReservedUnused(OSData, 5);
47 OSMetaClassDefineReservedUnused(OSData, 6);
48 OSMetaClassDefineReservedUnused(OSData, 7);
49 
50 #define EXTERNAL ((unsigned int) -1)
51 
52 #if OSALLOCDEBUG
53 extern int debug_container_malloc_size;
54 #define ACCUMSIZE(s) do { debug_container_malloc_size += (s); } while(0)
55 #else
56 #define ACCUMSIZE(s)
57 #endif
58 
59 bool OSData::initWithCapacity(unsigned int inCapacity)
60 {
61     if (!super::init())
62         return false;
63 
64     if (data && (!inCapacity || capacity < inCapacity) ) {
65         // clean out old data's storage if it isn't big enough
66         kfree(data, capacity);
67         data = 0;
68         ACCUMSIZE(-capacity);
69     }
70 
71     if (inCapacity && !data) {
72         data = (void *) kalloc(inCapacity);
73         if (!data)
74             return false;
75         capacity = inCapacity;
76         ACCUMSIZE(inCapacity);
77     }
78 
79     length = 0;
80     if (inCapacity < 16)
81         capacityIncrement = 16;
82     else
83         capacityIncrement = inCapacity;
84 
85     return true;
86 }
87 
88 bool OSData::initWithBytes(const void *bytes, unsigned int inLength)
89 {
90     if ((inLength && !bytes) || !initWithCapacity(inLength))
91         return false;
92 
93     if (bytes != data)
94 	bcopy(bytes, data, inLength);
95     length = inLength;
96 
97     return true;
98 }
99 
100 bool OSData::initWithBytesNoCopy(void *bytes, unsigned int inLength)
101 {
102     if (!super::init())
103         return false;
104 
105     length = inLength;
106     capacity = EXTERNAL;
107     data = bytes;
108 
109     return true;
110 }
111 
112 bool OSData::initWithData(const OSData *inData)
113 {
114     return initWithBytes(inData->data, inData->length);
115 }
116 
117 bool OSData::initWithData(const OSData *inData,
118                           unsigned int start, unsigned int inLength)
119 {
120     const void *localData = inData->getBytesNoCopy(start, inLength);
121 
122     if (localData)
123         return initWithBytes(localData, inLength);
124     else
125         return false;
126 }
127 
128 OSData *OSData::withCapacity(unsigned int inCapacity)
129 {
130     OSData *me = new OSData;
131 
132     if (me && !me->initWithCapacity(inCapacity)) {
133         me->release();
134         return 0;
135     }
136 
137     return me;
138 }
139 
140 OSData *OSData::withBytes(const void *bytes, unsigned int inLength)
141 {
142     OSData *me = new OSData;
143 
144     if (me && !me->initWithBytes(bytes, inLength)) {
145         me->release();
146         return 0;
147     }
148     return me;
149 }
150 
151 OSData *OSData::withBytesNoCopy(void *bytes, unsigned int inLength)
152 {
153     OSData *me = new OSData;
154 
155     if (me && !me->initWithBytesNoCopy(bytes, inLength)) {
156         me->release();
157         return 0;
158     }
159 
160     return me;
161 }
162 
163 OSData *OSData::withData(const OSData *inData)
164 {
165     OSData *me = new OSData;
166 
167     if (me && !me->initWithData(inData)) {
168         me->release();
169         return 0;
170     }
171 
172     return me;
173 }
174 
175 OSData *OSData::withData(const OSData *inData,
176                          unsigned int start, unsigned int inLength)
177 {
178     OSData *me = new OSData;
179 
180     if (me && !me->initWithData(inData, start, inLength)) {
181         me->release();
182         return 0;
183     }
184 
185     return me;
186 }
187 
188 void OSData::free()
189 {
190     if (capacity != EXTERNAL && data && capacity) {
191         kfree(data, capacity);
192         ACCUMSIZE( -capacity );
193     } else if (capacity == EXTERNAL) {
194 	    DeallocFunction freemem = (DeallocFunction)reserved;
195 		if (freemem && data && length) {
196 			freemem(data, length);
197 		}
198 	}
199     super::free();
200 }
201 
202 unsigned int OSData::getLength() const { return length; }
203 unsigned int OSData::getCapacity() const { return capacity; }
204 
205 unsigned int OSData::getCapacityIncrement() const
206 {
207     return capacityIncrement;
208 }
209 
210 unsigned int OSData::setCapacityIncrement(unsigned increment)
211 {
212     return capacityIncrement = increment;
213 }
214 
215 // xx-review: does not check for capacity == EXTERNAL
216 
217 unsigned int OSData::ensureCapacity(unsigned int newCapacity)
218 {
219     unsigned char * newData;
220 
221     if (newCapacity <= capacity)
222         return capacity;
223 
224     newCapacity = (((newCapacity - 1) / capacityIncrement) + 1)
225                 * capacityIncrement;
226 
227     newData = (unsigned char *) kalloc(newCapacity);
228 
229     if ( newData ) {
230         bzero(newData + capacity, newCapacity - capacity);
231         if (data) {
232             bcopy(data, newData, capacity);
233             kfree(data, capacity);
234         }
235         ACCUMSIZE( newCapacity - capacity );
236         data = (void *) newData;
237         capacity = newCapacity;
238     }
239 
240     return capacity;
241 }
242 
243 bool OSData::appendBytes(const void *bytes, unsigned int inLength)
244 {
245     unsigned int newSize;
246 
247     if (!inLength)
248         return true;
249 
250     if (capacity == EXTERNAL)
251         return false;
252 
253     newSize = length + inLength;
254     if ( (newSize > capacity) && newSize > ensureCapacity(newSize) )
255         return false;
256 
257     if (bytes)
258         bcopy(bytes, &((unsigned char *)data)[length], inLength);
259     else
260         bzero(&((unsigned char *)data)[length], inLength);
261 
262     length = newSize;
263 
264     return true;
265 }
266 
267 bool OSData::appendByte(unsigned char byte, unsigned int inLength)
268 {
269     unsigned int newSize;
270 
271     if (!inLength)
272         return true;
273 
274     if (capacity == EXTERNAL)
275         return false;
276 
277     newSize = length + inLength;
278     if ( (newSize > capacity) && newSize > ensureCapacity(newSize) )
279         return false;
280 
281     memset(&((unsigned char *)data)[length], byte, inLength);
282     length = newSize;
283 
284     return true;
285 }
286 
287 bool OSData::appendBytes(const OSData *other)
288 {
289     return appendBytes(other->data, other->length);
290 }
291 
292 const void *OSData::getBytesNoCopy() const
293 {
294     if (!length)
295         return 0;
296     else
297         return data;
298 }
299 
300 const void *OSData::getBytesNoCopy(unsigned int start,
301                                    unsigned int inLength) const
302 {
303     const void *outData = 0;
304 
305     if (length
306     &&  start < length
307     && (start + inLength) <= length)
308         outData = (const void *) ((char *) data + start);
309 
310     return outData;
311 }
312 
313 bool OSData::isEqualTo(const OSData *aData) const
314 {
315     unsigned int len;
316 
317     len = aData->length;
318     if ( length != len )
319         return false;
320 
321     return isEqualTo(aData->data, len);
322 }
323 
324 bool OSData::isEqualTo(const void *someData, unsigned int inLength) const
325 {
326     return (length >= inLength) && (bcmp(data, someData, inLength) == 0);
327 }
328 
329 bool OSData::isEqualTo(const OSMetaClassBase *obj) const
330 {
331     OSData *	otherData;
332     OSString *  str;
333 
334     if ((otherData = OSDynamicCast(OSData, obj)))
335         return isEqualTo(otherData);
336     else if ((str = OSDynamicCast (OSString, obj)))
337         return isEqualTo(str);
338     else
339         return false;
340 }
341 
342 bool OSData::isEqualTo(const OSString *obj) const
343 {
344     const char * aCString;
345     char * dataPtr;
346     unsigned int checkLen = length;
347     unsigned int stringLen;
348 
349     if (!obj)
350       return false;
351 
352     stringLen = obj->getLength ();
353 
354     dataPtr = (char *)data;
355 
356     if (stringLen != checkLen) {
357 
358       // check for the fact that OSData may be a buffer that
359       // that includes a termination byte and will thus have
360       // a length of the actual string length PLUS 1. In this
361       // case we verify that the additional byte is a terminator
362       // and if so count the two lengths as being the same.
363 
364       if ( (checkLen - stringLen) == 1) {
365 	if (dataPtr[checkLen-1] != 0) // non-zero means not a terminator and thus not likely the same
366 	  return false;
367         checkLen--;
368       }
369       else
370 	return false;
371     }
372 
373     aCString = obj->getCStringNoCopy ();
374 
375     for ( unsigned int i=0; i < checkLen; i++ ) {
376       if ( *dataPtr++ != aCString[i] )
377         return false;
378     }
379 
380    return true;
381 }
382 
383 //this was taken from CFPropertyList.c
384 static const char __CFPLDataEncodeTable[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
385 
386 bool OSData::serialize(OSSerialize *s) const
387 {
388     unsigned int i;
389     const unsigned char *p;
390     unsigned char c;
391 
392     if (s->previouslySerialized(this)) return true;
393 
394     if (!s->addXMLStartTag(this, "data")) return false;
395 
396     for (i = 0, p = (unsigned char *)data; i < length; i++, p++) {
397         /* 3 bytes are encoded as 4 */
398         switch (i % 3) {
399 	case 0:
400 		c = __CFPLDataEncodeTable [ ((p[0] >> 2) & 0x3f)];
401 		if (!s->addChar(c)) return false;
402 		break;
403 	case 1:
404 		c = __CFPLDataEncodeTable [ ((((p[-1] << 8) | p[0]) >> 4) & 0x3f)];
405 		if (!s->addChar(c)) return false;
406 		break;
407 	case 2:
408 		c = __CFPLDataEncodeTable [ ((((p[-1] << 8) | p[0]) >> 6) & 0x3f)];
409 		if (!s->addChar(c)) return false;
410 		c = __CFPLDataEncodeTable [ (p[0] & 0x3f)];
411 		if (!s->addChar(c)) return false;
412 		break;
413 	}
414     }
415     switch (i % 3) {
416     case 0:
417 	    break;
418     case 1:
419 	    c = __CFPLDataEncodeTable [ ((p[-1] << 4) & 0x30)];
420 	    if (!s->addChar(c)) return false;
421 	    if (!s->addChar('=')) return false;
422 	    if (!s->addChar('=')) return false;
423 	    break;
424     case 2:
425 	    c = __CFPLDataEncodeTable [ ((p[-1] << 2) & 0x3c)];
426 	    if (!s->addChar(c)) return false;
427 	    if (!s->addChar('=')) return false;
428 	    break;
429     }
430 
431     return s->addXMLEndTag("data");
432 }
433 
434 /* Note I am just using the reserved pointer here instead of allocating a whole buffer
435  * to hold one pointer.
436  */
437 void OSData::setDeallocFunction(DeallocFunction func)
438 {
439     reserved = (ExpansionData *)func;
440 	return;
441 }
442