1/*
2 * Copyright (c) 2000-2001,2011,2014 Apple Inc. All Rights Reserved.
3 *
4 * The contents of this file constitute Original Code as defined in and are
5 * subject to the Apple Public Source License Version 1.2 (the 'License').
6 * You may not use this file except in compliance with the License. Please obtain
7 * a copy of the License at http://www.apple.com/publicsource and read it before
8 * using this file.
9 *
10 * This Original Code and all software distributed under the License are
11 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS
12 * OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, INCLUDING WITHOUT
13 * LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
14 * PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. Please see the License for the
15 * specific language governing rights and limitations under the License.
16 */
17
18
19//
20// MetaAttribute.cpp
21//
22
23#include "MetaAttribute.h"
24#include "MetaRecord.h"
25
26MetaAttribute::~MetaAttribute()
27{
28}
29
30// Construct an instance of an appropriate subclass of MetaAttribute
31// based on the given format.
32
33MetaAttribute *
34MetaAttribute::create(Format format, uint32 attributeIndex,
35	uint32 attributeId)
36{
37	switch (format)
38	{
39		case CSSM_DB_ATTRIBUTE_FORMAT_STRING:
40			return new TypedMetaAttribute<StringValue>(format, attributeIndex, attributeId);
41
42		case CSSM_DB_ATTRIBUTE_FORMAT_SINT32:
43			return new TypedMetaAttribute<SInt32Value>(format, attributeIndex, attributeId);
44
45		case CSSM_DB_ATTRIBUTE_FORMAT_UINT32:
46			return new TypedMetaAttribute<UInt32Value>(format, attributeIndex, attributeId);
47
48		case CSSM_DB_ATTRIBUTE_FORMAT_BIG_NUM:
49			return new TypedMetaAttribute<BigNumValue>(format, attributeIndex, attributeId);
50
51		case CSSM_DB_ATTRIBUTE_FORMAT_REAL:
52			return new TypedMetaAttribute<DoubleValue>(format, attributeIndex, attributeId);
53
54		case CSSM_DB_ATTRIBUTE_FORMAT_TIME_DATE:
55			return new TypedMetaAttribute<TimeDateValue>(format, attributeIndex, attributeId);
56
57		case CSSM_DB_ATTRIBUTE_FORMAT_BLOB:
58			return new TypedMetaAttribute<BlobValue>(format, attributeIndex, attributeId);
59
60		case CSSM_DB_ATTRIBUTE_FORMAT_MULTI_UINT32:
61			return new TypedMetaAttribute<MultiUInt32Value>(format, attributeIndex, attributeId);
62
63	    case CSSM_DB_ATTRIBUTE_FORMAT_COMPLEX:
64		default:
65			CssmError::throwMe(CSSMERR_DL_UNSUPPORTED_FIELD_FORMAT);
66	}
67}
68
69void
70MetaAttribute::packNumberOfValues(WriteSection &ws, uint32 numValues, uint32 &valueOffset) const
71{
72	uint32 offset = MetaRecord::OffsetAttributeOffsets + mAttributeIndex * AtomSize;
73
74	if (numValues == 0) {
75		// a zero offset means the attribute has no values
76		ws.put(offset, 0);
77	}
78	else if (numValues == 1) {
79		// setting the low bit of the offset means that there is exactly one value
80		 ws.put(offset, valueOffset | 1);
81	}
82	else {
83		// write the offset, then write the number of values at that position
84		ws.put(offset, valueOffset);
85		valueOffset = ws.put(valueOffset, numValues);
86	}
87}
88
89void
90MetaAttribute::unpackNumberOfValues(const ReadSection &rs, uint32 &numValues,
91	uint32 &valueOffset) const
92{
93	uint32 offset = MetaRecord::OffsetAttributeOffsets + mAttributeIndex * AtomSize;
94	valueOffset = rs[offset];
95
96	if (valueOffset == 0)
97		// a zero offset means no values
98		numValues = 0;
99	else if (valueOffset & 1) {
100		// setting the LSB means exactly one value
101		valueOffset ^= 1;
102		numValues = 1;
103	}
104	else {
105		// otherwise, the number of values is at the offset, and the values follow
106		numValues = rs[valueOffset];
107		valueOffset += AtomSize;
108	}
109}
110
111void
112MetaAttribute::packAttribute(WriteSection &ws, uint32 &valueOffset, uint32 numValues,
113	const CSSM_DATA *values) const
114{
115	packNumberOfValues(ws, numValues, valueOffset);
116	for (uint32 i = 0; i < numValues; i++)
117		packValue(ws, valueOffset, values[i]);
118}
119
120void
121MetaAttribute::unpackAttribute(const ReadSection &rs, Allocator &allocator,
122	uint32 &numValues, CSSM_DATA *&values) const
123{
124	uint32 valueOffset;
125	unpackNumberOfValues(rs, numValues, valueOffset);
126
127	// Rough check for number of values; will be more like 10 or 20
128	if (numValues > 1024)
129		CssmError::throwMe(CSSMERR_DL_DATABASE_CORRUPT);
130
131	values = reinterpret_cast<CSSM_DATA *>(allocator.malloc(numValues * sizeof(CSSM_DATA)));
132
133	for (uint32 i = 0; i < numValues; i++)
134		unpackValue(rs, valueOffset, values[i], allocator);
135}
136
137uint32
138MetaAttribute::getNumberOfValues(const ReadSection &rs) const
139{
140	uint32 numValues, valueOffset;
141	unpackNumberOfValues(rs, numValues, valueOffset);
142	return numValues;
143}
144
145void
146MetaAttribute::copyValueBytes(uint32 valueIndex, const ReadSection &rs, WriteSection &ws,
147	uint32 &writeOffset) const
148{
149	uint32 numValues, valueOffset;
150	unpackNumberOfValues(rs, numValues, valueOffset);
151
152	// skip bytes before the desired value
153	for (uint32 i = 0; i < valueIndex; i++)
154		skipValue(rs, valueOffset);
155
156	// copy the value bytes into the write section
157	copyValue(rs, valueOffset, ws, writeOffset);
158}
159