xref: /xnu-11215/libkern/c++/OSSerialize.cpp (revision e13b1fa5)
1 /*
2  * Copyright (c) 2000-2006 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
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,
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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.
14  *
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
19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
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27  */
28 /* OSSerialize.cpp created by rsulack on Wen 25-Nov-1998 */
29 
30 #include <sys/cdefs.h>
31 
32 __BEGIN_DECLS
33 #include <vm/vm_kern.h>
34 __END_DECLS
35 
36 #include <libkern/c++/OSContainers.h>
37 #include <libkern/c++/OSLib.h>
38 #include <libkern/c++/OSDictionary.h>
39 
40 #define super OSObject
41 
42 OSDefineMetaClassAndStructors(OSSerialize, OSObject)
43 OSMetaClassDefineReservedUnused(OSSerialize, 0);
44 OSMetaClassDefineReservedUnused(OSSerialize, 1);
45 OSMetaClassDefineReservedUnused(OSSerialize, 2);
46 OSMetaClassDefineReservedUnused(OSSerialize, 3);
47 OSMetaClassDefineReservedUnused(OSSerialize, 4);
48 OSMetaClassDefineReservedUnused(OSSerialize, 5);
49 OSMetaClassDefineReservedUnused(OSSerialize, 6);
50 OSMetaClassDefineReservedUnused(OSSerialize, 7);
51 
52 #if OSALLOCDEBUG
53 extern "C" {
54     extern int debug_container_malloc_size;
55 };
56 #define ACCUMSIZE(s) do { debug_container_malloc_size += (s); } while(0)
57 #else
58 #define ACCUMSIZE(s)
59 #endif
60 
61 char * OSSerialize::text() const
62 {
63 	return data;
64 }
65 
66 void OSSerialize::clearText()
67 {
68 	bzero((void *)data, capacity);
69 	length = 1;
70 	tag = 0;
71 	tags->flushCollection();
72 }
73 
74 bool OSSerialize::previouslySerialized(const OSMetaClassBase *o)
75 {
76 	char temp[16];
77 	OSString *tagString;
78 
79 	// look it up
80 	tagString = (OSString *)tags->getObject((const OSSymbol *) o);
81 
82 	// does it exist?
83 	if (tagString) {
84 		addString("<reference IDREF=\"");
85 		addString(tagString->getCStringNoCopy());
86 		addString("\"/>");
87 		return true;
88 	}
89 
90 	// build a tag
91 	snprintf(temp, sizeof(temp), "%u", tag++);
92 	tagString = OSString::withCString(temp);
93 
94 	// add to tag dictionary
95         tags->setObject((const OSSymbol *) o, tagString);// XXX check return
96 	tagString->release();
97 
98 	return false;
99 }
100 
101 bool OSSerialize::addXMLStartTag(const OSMetaClassBase *o, const char *tagString)
102 {
103 
104 	if (!addChar('<')) return false;
105 	if (!addString(tagString)) return false;
106 	if (!addString(" ID=\"")) return false;
107 	if (!addString(((OSString *)tags->getObject((const OSSymbol *)o))->getCStringNoCopy()))
108 		return false;
109 	if (!addChar('\"')) return false;
110 	if (!addChar('>')) return false;
111 	return true;
112 }
113 
114 bool OSSerialize::addXMLEndTag(const char *tagString)
115 {
116 
117 	if (!addChar('<')) return false;
118 	if (!addChar('/')) return false;
119 	if (!addString(tagString)) return false;
120 	if (!addChar('>')) return false;
121 	return true;
122 }
123 
124 bool OSSerialize::addChar(const char c)
125 {
126 	// add char, possibly extending our capacity
127 	if (length >= capacity && length >=ensureCapacity(capacity+capacityIncrement))
128 		return false;
129 
130 	data[length - 1] = c;
131 	length++;
132 
133 	return true;
134 }
135 
136 bool OSSerialize::addString(const char *s)
137 {
138 	bool rc = false;
139 
140 	while (*s && (rc = addChar(*s++))) ;
141 
142 	return rc;
143 }
144 
145 bool OSSerialize::initWithCapacity(unsigned int inCapacity)
146 {
147     if (!super::init())
148             return false;
149 
150     tags = OSDictionary::withCapacity(32);
151     if (!tags) {
152         return false;
153     }
154 
155     tag = 0;
156     length = 1;
157     capacity = (inCapacity) ? round_page_32(inCapacity) : round_page_32(1);
158     capacityIncrement = capacity;
159 
160     // allocate from the kernel map so that we can safely map this data
161     // into user space (the primary use of the OSSerialize object)
162 
163     kern_return_t rc = kmem_alloc(kernel_map, (vm_offset_t *)&data, capacity);
164     if (rc) {
165         tags->release();
166         tags = 0;
167         return false;
168     }
169     bzero((void *)data, capacity);
170 
171 
172     ACCUMSIZE(capacity);
173 
174     return true;
175 }
176 
177 OSSerialize *OSSerialize::withCapacity(unsigned int inCapacity)
178 {
179 	OSSerialize *me = new OSSerialize;
180 
181 	if (me && !me->initWithCapacity(inCapacity)) {
182 		me->release();
183 		return 0;
184 	}
185 
186 	return me;
187 }
188 
189 unsigned int OSSerialize::getLength() const { return length; }
190 unsigned int OSSerialize::getCapacity() const { return capacity; }
191 unsigned int OSSerialize::getCapacityIncrement() const { return capacityIncrement; }
192 unsigned int OSSerialize::setCapacityIncrement(unsigned int increment)
193 {
194     capacityIncrement = (increment)? increment : 256;
195     return capacityIncrement;
196 }
197 
198 unsigned int OSSerialize::ensureCapacity(unsigned int newCapacity)
199 {
200 	char *newData;
201 
202 	if (newCapacity <= capacity)
203 		return capacity;
204 
205 	// round up
206 	newCapacity = round_page_32(newCapacity);
207 
208 	kern_return_t rc = kmem_realloc(kernel_map,
209 					(vm_offset_t)data,
210 					capacity,
211 					(vm_offset_t *)&newData,
212 					newCapacity);
213 	if (!rc) {
214 	    ACCUMSIZE(newCapacity);
215 
216 	    // kmem realloc does not free the old address range
217 	    kmem_free(kernel_map, (vm_offset_t)data, capacity);
218 	    ACCUMSIZE(-capacity);
219 
220 	    // kmem realloc does not zero out the new memory
221 	    // and this could end up going to user land
222 	    bzero(&newData[capacity], newCapacity - capacity);
223 
224 	    data = newData;
225 	    capacity = newCapacity;
226 	}
227 
228 	return capacity;
229 }
230 
231 void OSSerialize::free()
232 {
233     if (tags)
234         tags->release();
235 
236     if (data) {
237 	kmem_free(kernel_map, (vm_offset_t)data, capacity);
238         ACCUMSIZE( -capacity );
239     }
240     super::free();
241 }
242 
243 
244 OSDefineMetaClassAndStructors(OSSerializer, OSObject)
245 
246 OSSerializer * OSSerializer::forTarget( void * target,
247                                OSSerializerCallback callback, void * ref )
248 {
249     OSSerializer * thing;
250 
251     thing = new OSSerializer;
252     if( thing && !thing->init()) {
253 	thing->release();
254 	thing = 0;
255     }
256 
257     if( thing) {
258 	thing->target	= target;
259         thing->ref	= ref;
260         thing->callback = callback;
261     }
262     return( thing );
263 }
264 
265 bool OSSerializer::serialize( OSSerialize * s ) const
266 {
267     return( (*callback)(target, ref, s) );
268 }
269