aboutsummaryrefslogtreecommitdiff
path: root/drivers/acpi/acpica/exstorob.c
blob: 65a45d8335c8418882c8dff45b69966406270c06 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
/******************************************************************************
 *
 * Module Name: exstorob - AML Interpreter object store support, store to object
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2012, Intel Corp.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    substantially similar to the "NO WARRANTY" disclaimer below
 *    ("Disclaimer") and any redistribution must be conditioned upon
 *    including a substantially similar Disclaimer requirement for further
 *    binary redistribution.
 * 3. Neither the names of the above-listed copyright holders nor the names
 *    of any contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * NO WARRANTY
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGES.
 */

#include <acpi/acpi.h>
#include "accommon.h"
#include "acinterp.h"

#define _COMPONENT          ACPI_EXECUTER
ACPI_MODULE_NAME("exstorob")

/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_store_buffer_to_buffer
 *
 * PARAMETERS:  source_desc         - Source object to copy
 *              target_desc         - Destination object of the copy
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Copy a buffer object to another buffer object.
 *
 ******************************************************************************/
acpi_status
acpi_ex_store_buffer_to_buffer(union acpi_operand_object *source_desc,
			       union acpi_operand_object *target_desc)
{
	u32 length;
	u8 *buffer;

	ACPI_FUNCTION_TRACE_PTR(ex_store_buffer_to_buffer, source_desc);

	/* If Source and Target are the same, just return */

	if (source_desc == target_desc) {
		return_ACPI_STATUS(AE_OK);
	}

	/* We know that source_desc is a buffer by now */

	buffer = ACPI_CAST_PTR(u8, source_desc->buffer.pointer);
	length = source_desc->buffer.length;

	/*
	 * If target is a buffer of length zero or is a static buffer,
	 * allocate a new buffer of the proper length
	 */
	if ((target_desc->buffer.length == 0) ||
	    (target_desc->common.flags & AOPOBJ_STATIC_POINTER)) {
		target_desc->buffer.pointer = ACPI_ALLOCATE(length);
		if (!target_desc->buffer.pointer) {
			return_ACPI_STATUS(AE_NO_MEMORY);
		}

		target_desc->buffer.length = length;
	}

	/* Copy source buffer to target buffer */

	if (length <= target_desc->buffer.length) {

		/* Clear existing buffer and copy in the new one */

		ACPI_MEMSET(target_desc->buffer.pointer, 0,
			    target_desc->buffer.length);
		ACPI_MEMCPY(target_desc->buffer.pointer, buffer, length);

#ifdef ACPI_OBSOLETE_BEHAVIOR
		/*
		 * NOTE: ACPI versions up to 3.0 specified that the buffer must be
		 * truncated if the string is smaller than the buffer.  However, "other"
		 * implementations of ACPI never did this and thus became the defacto
		 * standard. ACPI 3.0_a changes this behavior such that the buffer
		 * is no longer truncated.
		 */

		/*
		 * OBSOLETE BEHAVIOR:
		 * If the original source was a string, we must truncate the buffer,
		 * according to the ACPI spec.  Integer-to-Buffer and Buffer-to-Buffer
		 * copy must not truncate the original buffer.
		 */
		if (original_src_type == ACPI_TYPE_STRING) {

			/* Set the new length of the target */

			target_desc->buffer.length = length;
		}
#endif
	} else {
		/* Truncate the source, copy only what will fit */

		ACPI_MEMCPY(target_desc->buffer.pointer, buffer,
			    target_desc->buffer.length);

		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "Truncating source buffer from %X to %X\n",
				  length, target_desc->buffer.length));
	}

	/* Copy flags */

	target_desc->buffer.flags = source_desc->buffer.flags;
	target_desc->common.flags &= ~AOPOBJ_STATIC_POINTER;
	return_ACPI_STATUS(AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_store_string_to_string
 *
 * PARAMETERS:  source_desc         - Source object to copy
 *              target_desc         - Destination object of the copy
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Copy a String object to another String object
 *
 ******************************************************************************/

acpi_status
acpi_ex_store_string_to_string(union acpi_operand_object *source_desc,
			       union acpi_operand_object *target_desc)
{
	u32 length;
	u8 *buffer;

	ACPI_FUNCTION_TRACE_PTR(ex_store_string_to_string, source_desc);

	/* If Source and Target are the same, just return */

	if (source_desc == target_desc) {
		return_ACPI_STATUS(AE_OK);
	}

	/* We know that source_desc is a string by now */

	buffer = ACPI_CAST_PTR(u8, source_desc->string.pointer);
	length = source_desc->string.length;

	/*
	 * Replace existing string value if it will fit and the string
	 * pointer is not a static pointer (part of an ACPI table)
	 */
	if ((length < target_desc->string.length) &&
	    (!(target_desc->common.flags & AOPOBJ_STATIC_POINTER))) {
		/*
		 * String will fit in existing non-static buffer.
		 * Clear old string and copy in the new one
		 */
		ACPI_MEMSET(target_desc->string.pointer, 0,
			    (acpi_size) target_desc->string.length + 1);
		ACPI_MEMCPY(target_desc->string.pointer, buffer, length);
	} else {
		/*
		 * Free the current buffer, then allocate a new buffer
		 * large enough to hold the value
		 */
		if (target_desc->string.pointer &&
		    (!(target_desc->common.flags & AOPOBJ_STATIC_POINTER))) {

			/* Only free if not a pointer into the DSDT */

			ACPI_FREE(target_desc->string.pointer);
		}

		target_desc->string.pointer = ACPI_ALLOCATE_ZEROED((acpi_size)
								   length + 1);
		if (!target_desc->string.pointer) {
			return_ACPI_STATUS(AE_NO_MEMORY);
		}

		target_desc->common.flags &= ~AOPOBJ_STATIC_POINTER;
		ACPI_MEMCPY(target_desc->string.pointer, buffer, length);
	}

	/* Set the new target length */

	target_desc->string.length = length;
	return_ACPI_STATUS(AE_OK);
}