xref: /xnu-11215/libkern/c++/OSSerialize.cpp (revision bb611c8f)
1 /*
2  * Copyright (c) 2000-2006 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 /* OSSerialize.cpp created by rsulack on Wen 25-Nov-1998 */
29 
30 #define IOKIT_ENABLE_SHARED_PTR
31 
32 #include <sys/cdefs.h>
33 
34 __BEGIN_DECLS
35 #include <vm/vm_kern.h>
36 __END_DECLS
37 
38 #include <libkern/c++/OSContainers.h>
39 #include <libkern/c++/OSLib.h>
40 #include <libkern/c++/OSDictionary.h>
41 #include <libkern/c++/OSSharedPtr.h>
42 #include <libkern/OSSerializeBinary.h>
43 #include <libkern/Block.h>
44 #include <IOKit/IOLib.h>
45 
46 #define super OSObject
47 
48 OSDefineMetaClassAndStructors(OSSerialize, OSObject)
49 OSMetaClassDefineReservedUnused(OSSerialize, 0);
50 OSMetaClassDefineReservedUnused(OSSerialize, 1);
51 OSMetaClassDefineReservedUnused(OSSerialize, 2);
52 OSMetaClassDefineReservedUnused(OSSerialize, 3);
53 OSMetaClassDefineReservedUnused(OSSerialize, 4);
54 OSMetaClassDefineReservedUnused(OSSerialize, 5);
55 OSMetaClassDefineReservedUnused(OSSerialize, 6);
56 OSMetaClassDefineReservedUnused(OSSerialize, 7);
57 
58 
59 char *
60 OSSerialize::text() const
61 {
62 	return data;
63 }
64 
65 void
66 OSSerialize::clearText()
67 {
68 	if (binary) {
69 		length = sizeof(kOSSerializeBinarySignature);
70 		bzero(&data[length], capacity - length);
71 		endCollection = true;
72 	} else {
73 		bzero((void *)data, capacity);
74 		length = 1;
75 	}
76 	tags->flushCollection();
77 }
78 
79 bool
80 OSSerialize::previouslySerialized(const OSMetaClassBase *o)
81 {
82 	char temp[16];
83 	unsigned int tagIdx;
84 
85 	if (binary) {
86 		return binarySerialize(o);
87 	}
88 
89 	// look it up
90 	tagIdx = tags->getNextIndexOfObject(o, 0);
91 
92 // xx-review: no error checking here for addString calls!
93 	// does it exist?
94 	if (tagIdx != -1U) {
95 		addString("<reference IDREF=\"");
96 		snprintf(temp, sizeof(temp), "%u", tagIdx);
97 		addString(temp);
98 		addString("\"/>");
99 		return true;
100 	}
101 
102 	// add to tag array
103 	tags->setObject(o);// XXX check return
104 
105 	return false;
106 }
107 
108 bool
109 OSSerialize::addXMLStartTag(const OSMetaClassBase *o, const char *tagString)
110 {
111 	char temp[16];
112 	unsigned int tagIdx;
113 
114 	if (binary) {
115 		printf("class %s: xml serialize\n", o->getMetaClass()->getClassName());
116 		return false;
117 	}
118 
119 	if (!addChar('<')) {
120 		return false;
121 	}
122 	if (!addString(tagString)) {
123 		return false;
124 	}
125 	if (!addString(" ID=\"")) {
126 		return false;
127 	}
128 	tagIdx = tags->getNextIndexOfObject(o, 0);
129 	assert(tagIdx != -1U);
130 	snprintf(temp, sizeof(temp), "%u", tagIdx);
131 	if (!addString(temp)) {
132 		return false;
133 	}
134 	if (!addChar('\"')) {
135 		return false;
136 	}
137 	if (!addChar('>')) {
138 		return false;
139 	}
140 	return true;
141 }
142 
143 bool
144 OSSerialize::addXMLEndTag(const char *tagString)
145 {
146 	if (!addChar('<')) {
147 		return false;
148 	}
149 	if (!addChar('/')) {
150 		return false;
151 	}
152 	if (!addString(tagString)) {
153 		return false;
154 	}
155 	if (!addChar('>')) {
156 		return false;
157 	}
158 	return true;
159 }
160 
161 bool
162 OSSerialize::addChar(const char c)
163 {
164 	if (binary) {
165 		printf("xml serialize\n");
166 		return false;
167 	}
168 
169 	// add char, possibly extending our capacity
170 	if (length >= capacity && length >= ensureCapacity(capacity + capacityIncrement)) {
171 		return false;
172 	}
173 
174 	data[length - 1] = c;
175 	length++;
176 
177 	return true;
178 }
179 
180 bool
181 OSSerialize::addString(const char *s)
182 {
183 	bool rc = false;
184 
185 	while (*s && (rc = addChar(*s++))) {
186 		;
187 	}
188 
189 	return rc;
190 }
191 
192 bool
193 OSSerialize::initWithCapacity(unsigned int inCapacity)
194 {
195 	if (!super::init()) {
196 		return false;
197 	}
198 
199 	tags = OSArray::withCapacity(256);
200 	if (!tags) {
201 		return false;
202 	}
203 
204 	length = 1;
205 
206 	if (!inCapacity) {
207 		inCapacity = 1;
208 	}
209 	if (round_page_overflow(inCapacity, &capacity)) {
210 		tags.reset();
211 		return false;
212 	}
213 
214 	capacityIncrement = capacity;
215 
216 	// allocate from the kernel map so that we can safely map this data
217 	// into user space (the primary use of the OSSerialize object)
218 
219 	kern_return_t rc = kmem_alloc(kernel_map, (vm_offset_t *)&data, capacity, IOMemoryTag(kernel_map));
220 	if (rc) {
221 		return false;
222 	}
223 	bzero((void *)data, capacity);
224 
225 
226 	OSCONTAINER_ACCUMSIZE(capacity);
227 
228 	return true;
229 }
230 
231 OSSharedPtr<OSSerialize>
232 OSSerialize::withCapacity(unsigned int inCapacity)
233 {
234 	OSSharedPtr<OSSerialize> me = OSMakeShared<OSSerialize>();
235 
236 	if (me && !me->initWithCapacity(inCapacity)) {
237 		return nullptr;
238 	}
239 
240 	return me;
241 }
242 
243 unsigned int
244 OSSerialize::getLength() const
245 {
246 	return length;
247 }
248 unsigned int
249 OSSerialize::getCapacity() const
250 {
251 	return capacity;
252 }
253 unsigned int
254 OSSerialize::getCapacityIncrement() const
255 {
256 	return capacityIncrement;
257 }
258 unsigned int
259 OSSerialize::setCapacityIncrement(unsigned int increment)
260 {
261 	capacityIncrement = (increment)? increment : 256;
262 	return capacityIncrement;
263 }
264 
265 unsigned int
266 OSSerialize::ensureCapacity(unsigned int newCapacity)
267 {
268 	char *newData;
269 
270 	if (newCapacity <= capacity) {
271 		return capacity;
272 	}
273 
274 	if (round_page_overflow(newCapacity, &newCapacity)) {
275 		return capacity;
276 	}
277 
278 	kern_return_t rc = kmem_realloc(kernel_map,
279 	    (vm_offset_t)data,
280 	    capacity,
281 	    (vm_offset_t *)&newData,
282 	    newCapacity,
283 	    VM_KERN_MEMORY_IOKIT);
284 	if (!rc) {
285 		OSCONTAINER_ACCUMSIZE(newCapacity);
286 
287 		// kmem realloc does not free the old address range
288 		kmem_free(kernel_map, (vm_offset_t)data, capacity);
289 		OSCONTAINER_ACCUMSIZE(-((size_t)capacity));
290 
291 		// kmem realloc does not zero out the new memory
292 		// and this could end up going to user land
293 		bzero(&newData[capacity], newCapacity - capacity);
294 
295 		data = newData;
296 		capacity = newCapacity;
297 	}
298 
299 	return capacity;
300 }
301 
302 void
303 OSSerialize::free()
304 {
305 	if (data) {
306 		kmem_free(kernel_map, (vm_offset_t)data, capacity);
307 		OSCONTAINER_ACCUMSIZE( -((size_t)capacity));
308 	}
309 	super::free();
310 }
311 
312 
313 OSDefineMetaClassAndStructors(OSSerializer, OSObject)
314 
315 OSSharedPtr<OSSerializer>
316 OSSerializer::forTarget( void * target,
317     OSSerializerCallback callback, void * ref )
318 {
319 	OSSharedPtr<OSSerializer> thing = OSMakeShared<OSSerializer>();
320 
321 	if (thing && !thing->init()) {
322 		thing.reset();
323 	}
324 
325 	if (thing) {
326 		thing->target   = target;
327 		thing->ref      = ref;
328 		thing->callback = callback;
329 	}
330 	return thing;
331 }
332 
333 bool
334 OSSerializer::callbackToBlock(void * target __unused, void * ref,
335     OSSerialize * serializer)
336 {
337 	return ((OSSerializerBlock)ref)(serializer);
338 }
339 
340 OSSharedPtr<OSSerializer>
341 OSSerializer::withBlock(
342 	OSSerializerBlock callback)
343 {
344 	OSSharedPtr<OSSerializer> serializer;
345 	OSSerializerBlock block;
346 
347 	block = Block_copy(callback);
348 	if (!block) {
349 		return NULL;
350 	}
351 
352 	serializer = (OSSerializer::forTarget(NULL, &OSSerializer::callbackToBlock, block));
353 
354 	if (!serializer) {
355 		Block_release(block);
356 	}
357 
358 	return serializer;
359 }
360 
361 void
362 OSSerializer::free(void)
363 {
364 	if (callback == &callbackToBlock) {
365 		Block_release(ref);
366 	}
367 
368 	super::free();
369 }
370 
371 bool
372 OSSerializer::serialize( OSSerialize * s ) const
373 {
374 	return (*callback)(target, ref, s);
375 }
376