xref: /xnu-11215/libkern/c++/OSData.cpp (revision 0f3703ac)
1 /*
2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
3  *
4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5  *
6  * This file contains Original Code and/or Modifications of Original Code
7  * as defined in and that are subject to the Apple Public Source License
8  * Version 2.0 (the 'License'). You may not use this file except in
9  * compliance with the License. The rights granted to you under the License
10  * may not be used to create, or enable the creation or redistribution of,
11  * unlawful or unlicensed copies of an Apple operating system, or to
12  * circumvent, violate, or enable the circumvention or violation of, any
13  * terms of an Apple operating system software license agreement.
14  *
15  * Please obtain a copy of the License at
16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17  *
18  * The Original Code and all software distributed under the License are
19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23  * Please see the License for the specific language governing rights and
24  * limitations under the License.
25  *
26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
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 bool OSData::initWithCapacity(unsigned int inCapacity)
53 {
54     if (data)
55     {
56         OSCONTAINER_ACCUMSIZE(-((size_t)capacity));
57 	if (!inCapacity || (capacity < inCapacity))
58 	{
59 	    // clean out old data's storage if it isn't big enough
60 	    kfree(data, capacity);
61 	    data = 0;
62 	    capacity = 0;
63 	}
64     }
65 
66     if (!super::init())
67         return false;
68 
69     if (inCapacity && !data) {
70         data = (void *) kalloc_container(inCapacity);
71         if (!data)
72             return false;
73         capacity = inCapacity;
74     }
75     OSCONTAINER_ACCUMSIZE(capacity);
76 
77     length = 0;
78     if (inCapacity < 16)
79         capacityIncrement = 16;
80     else
81         capacityIncrement = inCapacity;
82 
83     return true;
84 }
85 
86 bool OSData::initWithBytes(const void *bytes, unsigned int inLength)
87 {
88     if ((inLength && !bytes) || !initWithCapacity(inLength))
89         return false;
90 
91     if (bytes != data)
92 	bcopy(bytes, data, inLength);
93     length = inLength;
94 
95     return true;
96 }
97 
98 bool OSData::initWithBytesNoCopy(void *bytes, unsigned int inLength)
99 {
100     if (!super::init())
101         return false;
102 
103     length = inLength;
104     capacity = EXTERNAL;
105     data = bytes;
106 
107     return true;
108 }
109 
110 bool OSData::initWithData(const OSData *inData)
111 {
112     return initWithBytes(inData->data, inData->length);
113 }
114 
115 bool OSData::initWithData(const OSData *inData,
116                           unsigned int start, unsigned int inLength)
117 {
118     const void *localData = inData->getBytesNoCopy(start, inLength);
119 
120     if (localData)
121         return initWithBytes(localData, inLength);
122     else
123         return false;
124 }
125 
126 OSData *OSData::withCapacity(unsigned int inCapacity)
127 {
128     OSData *me = new OSData;
129 
130     if (me && !me->initWithCapacity(inCapacity)) {
131         me->release();
132         return 0;
133     }
134 
135     return me;
136 }
137 
138 OSData *OSData::withBytes(const void *bytes, unsigned int inLength)
139 {
140     OSData *me = new OSData;
141 
142     if (me && !me->initWithBytes(bytes, inLength)) {
143         me->release();
144         return 0;
145     }
146     return me;
147 }
148 
149 OSData *OSData::withBytesNoCopy(void *bytes, unsigned int inLength)
150 {
151     OSData *me = new OSData;
152 
153     if (me && !me->initWithBytesNoCopy(bytes, inLength)) {
154         me->release();
155         return 0;
156     }
157 
158     return me;
159 }
160 
161 OSData *OSData::withData(const OSData *inData)
162 {
163     OSData *me = new OSData;
164 
165     if (me && !me->initWithData(inData)) {
166         me->release();
167         return 0;
168     }
169 
170     return me;
171 }
172 
173 OSData *OSData::withData(const OSData *inData,
174                          unsigned int start, unsigned int inLength)
175 {
176     OSData *me = new OSData;
177 
178     if (me && !me->initWithData(inData, start, inLength)) {
179         me->release();
180         return 0;
181     }
182 
183     return me;
184 }
185 
186 void OSData::free()
187 {
188     if (capacity != EXTERNAL && data && capacity) {
189         kfree(data, capacity);
190         OSCONTAINER_ACCUMSIZE( -((size_t)capacity) );
191     } else if (capacity == EXTERNAL) {
192 	DeallocFunction freemem = reserved ? reserved->deallocFunction : NULL;
193 	if (freemem && data && length) {
194 		freemem(data, length);
195 	}
196     }
197     if (reserved) kfree(reserved, sizeof(ExpansionData));
198     super::free();
199 }
200 
201 unsigned int OSData::getLength() const { return length; }
202 unsigned int OSData::getCapacity() const { return capacity; }
203 
204 unsigned int OSData::getCapacityIncrement() const
205 {
206     return capacityIncrement;
207 }
208 
209 unsigned int OSData::setCapacityIncrement(unsigned increment)
210 {
211     return capacityIncrement = increment;
212 }
213 
214 // xx-review: does not check for capacity == EXTERNAL
215 
216 unsigned int OSData::ensureCapacity(unsigned int newCapacity)
217 {
218     unsigned char * newData;
219     unsigned int finalCapacity;
220 
221     if (newCapacity <= capacity)
222         return capacity;
223 
224     finalCapacity = (((newCapacity - 1) / capacityIncrement) + 1)
225                 * capacityIncrement;
226 
227     // integer overflow check
228     if (finalCapacity < newCapacity)
229         return capacity;
230 
231     newData = (unsigned char *) kalloc_container(finalCapacity);
232 
233     if ( newData ) {
234         bzero(newData + capacity, finalCapacity - capacity);
235         if (data) {
236             bcopy(data, newData, capacity);
237             kfree(data, capacity);
238         }
239         OSCONTAINER_ACCUMSIZE( ((size_t)finalCapacity) - ((size_t)capacity) );
240         data = (void *) newData;
241         capacity = finalCapacity;
242     }
243 
244     return capacity;
245 }
246 
247 bool OSData::appendBytes(const void *bytes, unsigned int inLength)
248 {
249     unsigned int newSize;
250 
251     if (!inLength)
252         return true;
253 
254     if (capacity == EXTERNAL)
255         return false;
256 
257     newSize = length + inLength;
258     if ( (newSize > capacity) && newSize > ensureCapacity(newSize) )
259         return false;
260 
261     if (bytes)
262         bcopy(bytes, &((unsigned char *)data)[length], inLength);
263     else
264         bzero(&((unsigned char *)data)[length], inLength);
265 
266     length = newSize;
267 
268     return true;
269 }
270 
271 bool OSData::appendByte(unsigned char byte, unsigned int inLength)
272 {
273     unsigned int newSize;
274 
275     if (!inLength)
276         return true;
277 
278     if (capacity == EXTERNAL)
279         return false;
280 
281     newSize = length + inLength;
282     if ( (newSize > capacity) && newSize > ensureCapacity(newSize) )
283         return false;
284 
285     memset(&((unsigned char *)data)[length], byte, inLength);
286     length = newSize;
287 
288     return true;
289 }
290 
291 bool OSData::appendBytes(const OSData *other)
292 {
293     return appendBytes(other->data, other->length);
294 }
295 
296 const void *OSData::getBytesNoCopy() const
297 {
298     if (!length)
299         return 0;
300     else
301         return data;
302 }
303 
304 const void *OSData::getBytesNoCopy(unsigned int start,
305                                    unsigned int inLength) const
306 {
307     const void *outData = 0;
308 
309     if (length
310     &&  start < length
311     && (start + inLength) <= length)
312         outData = (const void *) ((char *) data + start);
313 
314     return outData;
315 }
316 
317 bool OSData::isEqualTo(const OSData *aData) const
318 {
319     unsigned int len;
320 
321     len = aData->length;
322     if ( length != len )
323         return false;
324 
325     return isEqualTo(aData->data, len);
326 }
327 
328 bool OSData::isEqualTo(const void *someData, unsigned int inLength) const
329 {
330     return (length >= inLength) && (bcmp(data, someData, inLength) == 0);
331 }
332 
333 bool OSData::isEqualTo(const OSMetaClassBase *obj) const
334 {
335     OSData *	otherData;
336     OSString *  str;
337 
338     if ((otherData = OSDynamicCast(OSData, obj)))
339         return isEqualTo(otherData);
340     else if ((str = OSDynamicCast (OSString, obj)))
341         return isEqualTo(str);
342     else
343         return false;
344 }
345 
346 bool OSData::isEqualTo(const OSString *obj) const
347 {
348     const char * aCString;
349     char * dataPtr;
350     unsigned int checkLen = length;
351     unsigned int stringLen;
352 
353     if (!obj)
354       return false;
355 
356     stringLen = obj->getLength ();
357 
358     dataPtr = (char *)data;
359 
360     if (stringLen != checkLen) {
361 
362       // check for the fact that OSData may be a buffer that
363       // that includes a termination byte and will thus have
364       // a length of the actual string length PLUS 1. In this
365       // case we verify that the additional byte is a terminator
366       // and if so count the two lengths as being the same.
367 
368       if ( (checkLen - stringLen) == 1) {
369 	if (dataPtr[checkLen-1] != 0) // non-zero means not a terminator and thus not likely the same
370 	  return false;
371         checkLen--;
372       }
373       else
374 	return false;
375     }
376 
377     aCString = obj->getCStringNoCopy ();
378 
379     for ( unsigned int i=0; i < checkLen; i++ ) {
380       if ( *dataPtr++ != aCString[i] )
381         return false;
382     }
383 
384    return true;
385 }
386 
387 //this was taken from CFPropertyList.c
388 static const char __CFPLDataEncodeTable[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
389 
390 bool OSData::serialize(OSSerialize *s) const
391 {
392     unsigned int i;
393     const unsigned char *p;
394     unsigned char c;
395     unsigned int serializeLength;
396 
397     if (s->previouslySerialized(this)) return true;
398 
399     if (!s->addXMLStartTag(this, "data")) return false;
400 
401     serializeLength = length;
402     if (reserved && reserved->disableSerialization) serializeLength = 0;
403 
404     for (i = 0, p = (unsigned char *)data; i < serializeLength; i++, p++) {
405         /* 3 bytes are encoded as 4 */
406         switch (i % 3) {
407 	case 0:
408 		c = __CFPLDataEncodeTable [ ((p[0] >> 2) & 0x3f)];
409 		if (!s->addChar(c)) return false;
410 		break;
411 	case 1:
412 		c = __CFPLDataEncodeTable [ ((((p[-1] << 8) | p[0]) >> 4) & 0x3f)];
413 		if (!s->addChar(c)) return false;
414 		break;
415 	case 2:
416 		c = __CFPLDataEncodeTable [ ((((p[-1] << 8) | p[0]) >> 6) & 0x3f)];
417 		if (!s->addChar(c)) return false;
418 		c = __CFPLDataEncodeTable [ (p[0] & 0x3f)];
419 		if (!s->addChar(c)) return false;
420 		break;
421 	}
422     }
423     switch (i % 3) {
424     case 0:
425 	    break;
426     case 1:
427 	    c = __CFPLDataEncodeTable [ ((p[-1] << 4) & 0x30)];
428 	    if (!s->addChar(c)) return false;
429 	    if (!s->addChar('=')) return false;
430 	    if (!s->addChar('=')) return false;
431 	    break;
432     case 2:
433 	    c = __CFPLDataEncodeTable [ ((p[-1] << 2) & 0x3c)];
434 	    if (!s->addChar(c)) return false;
435 	    if (!s->addChar('=')) return false;
436 	    break;
437     }
438 
439     return s->addXMLEndTag("data");
440 }
441 
442 void OSData::setDeallocFunction(DeallocFunction func)
443 {
444     if (!reserved)
445     {
446     	reserved = (typeof(reserved)) kalloc_container(sizeof(ExpansionData));
447         if (!reserved) return;
448         bzero(reserved, sizeof(ExpansionData));
449     }
450     reserved->deallocFunction = func;
451 }
452 
453 void OSData::setSerializable(bool serializable)
454 {
455     if (!reserved)
456     {
457     	reserved = (typeof(reserved)) kalloc_container(sizeof(ExpansionData));
458 	if (!reserved) return;
459 	bzero(reserved, sizeof(ExpansionData));
460     }
461     reserved->disableSerialization = (!serializable);
462 }
463