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Linux kernel mirror (for testing)
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1/*******************************************************************************
2 *
3 * Module Name: nsnames - Name manipulation and search
4 *
5 ******************************************************************************/
6
7/*
8 * Copyright (C) 2000 - 2005, R. Byron Moore
9 * All rights reserved.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions, and the following disclaimer,
16 * without modification.
17 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18 * substantially similar to the "NO WARRANTY" disclaimer below
19 * ("Disclaimer") and any redistribution must be conditioned upon
20 * including a substantially similar Disclaimer requirement for further
21 * binary redistribution.
22 * 3. Neither the names of the above-listed copyright holders nor the names
23 * of any contributors may be used to endorse or promote products derived
24 * from this software without specific prior written permission.
25 *
26 * Alternatively, this software may be distributed under the terms of the
27 * GNU General Public License ("GPL") version 2 as published by the Free
28 * Software Foundation.
29 *
30 * NO WARRANTY
31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41 * POSSIBILITY OF SUCH DAMAGES.
42 */
43
44#include <acpi/acpi.h>
45#include <acpi/amlcode.h>
46#include <acpi/acnamesp.h>
47
48#define _COMPONENT ACPI_NAMESPACE
49ACPI_MODULE_NAME("nsnames")
50
51/* Local prototypes */
52static void
53acpi_ns_build_external_path(struct acpi_namespace_node *node,
54 acpi_size size, char *name_buffer);
55
56/*******************************************************************************
57 *
58 * FUNCTION: acpi_ns_build_external_path
59 *
60 * PARAMETERS: Node - NS node whose pathname is needed
61 * Size - Size of the pathname
62 * *name_buffer - Where to return the pathname
63 *
64 * RETURN: Places the pathname into the name_buffer, in external format
65 * (name segments separated by path separators)
66 *
67 * DESCRIPTION: Generate a full pathaname
68 *
69 ******************************************************************************/
70
71static void
72acpi_ns_build_external_path(struct acpi_namespace_node *node,
73 acpi_size size, char *name_buffer)
74{
75 acpi_size index;
76 struct acpi_namespace_node *parent_node;
77
78 ACPI_FUNCTION_NAME("ns_build_external_path");
79
80 /* Special case for root */
81
82 index = size - 1;
83 if (index < ACPI_NAME_SIZE) {
84 name_buffer[0] = AML_ROOT_PREFIX;
85 name_buffer[1] = 0;
86 return;
87 }
88
89 /* Store terminator byte, then build name backwards */
90
91 parent_node = node;
92 name_buffer[index] = 0;
93
94 while ((index > ACPI_NAME_SIZE) && (parent_node != acpi_gbl_root_node)) {
95 index -= ACPI_NAME_SIZE;
96
97 /* Put the name into the buffer */
98
99 ACPI_MOVE_32_TO_32((name_buffer + index), &parent_node->name);
100 parent_node = acpi_ns_get_parent_node(parent_node);
101
102 /* Prefix name with the path separator */
103
104 index--;
105 name_buffer[index] = ACPI_PATH_SEPARATOR;
106 }
107
108 /* Overwrite final separator with the root prefix character */
109
110 name_buffer[index] = AML_ROOT_PREFIX;
111
112 if (index != 0) {
113 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
114 "Could not construct pathname; index=%X, size=%X, Path=%s\n",
115 (u32) index, (u32) size, &name_buffer[size]));
116 }
117
118 return;
119}
120
121#ifdef ACPI_DEBUG_OUTPUT
122/*******************************************************************************
123 *
124 * FUNCTION: acpi_ns_get_external_pathname
125 *
126 * PARAMETERS: Node - Namespace node whose pathname is needed
127 *
128 * RETURN: Pointer to storage containing the fully qualified name of
129 * the node, In external format (name segments separated by path
130 * separators.)
131 *
132 * DESCRIPTION: Used for debug printing in acpi_ns_search_table().
133 *
134 ******************************************************************************/
135
136char *acpi_ns_get_external_pathname(struct acpi_namespace_node *node)
137{
138 char *name_buffer;
139 acpi_size size;
140
141 ACPI_FUNCTION_TRACE_PTR("ns_get_external_pathname", node);
142
143 /* Calculate required buffer size based on depth below root */
144
145 size = acpi_ns_get_pathname_length(node);
146
147 /* Allocate a buffer to be returned to caller */
148
149 name_buffer = ACPI_MEM_CALLOCATE(size);
150 if (!name_buffer) {
151 ACPI_REPORT_ERROR(("ns_get_table_pathname: allocation failure\n"));
152 return_PTR(NULL);
153 }
154
155 /* Build the path in the allocated buffer */
156
157 acpi_ns_build_external_path(node, size, name_buffer);
158 return_PTR(name_buffer);
159}
160#endif
161
162/*******************************************************************************
163 *
164 * FUNCTION: acpi_ns_get_pathname_length
165 *
166 * PARAMETERS: Node - Namespace node
167 *
168 * RETURN: Length of path, including prefix
169 *
170 * DESCRIPTION: Get the length of the pathname string for this node
171 *
172 ******************************************************************************/
173
174acpi_size acpi_ns_get_pathname_length(struct acpi_namespace_node *node)
175{
176 acpi_size size;
177 struct acpi_namespace_node *next_node;
178
179 ACPI_FUNCTION_ENTRY();
180
181 /*
182 * Compute length of pathname as 5 * number of name segments.
183 * Go back up the parent tree to the root
184 */
185 size = 0;
186 next_node = node;
187
188 while (next_node && (next_node != acpi_gbl_root_node)) {
189 size += ACPI_PATH_SEGMENT_LENGTH;
190 next_node = acpi_ns_get_parent_node(next_node);
191 }
192
193 if (!size) {
194 size = 1; /* Root node case */
195 }
196
197 return (size + 1); /* +1 for null string terminator */
198}
199
200/*******************************************************************************
201 *
202 * FUNCTION: acpi_ns_handle_to_pathname
203 *
204 * PARAMETERS: target_handle - Handle of named object whose name is
205 * to be found
206 * Buffer - Where the pathname is returned
207 *
208 * RETURN: Status, Buffer is filled with pathname if status is AE_OK
209 *
210 * DESCRIPTION: Build and return a full namespace pathname
211 *
212 ******************************************************************************/
213
214acpi_status
215acpi_ns_handle_to_pathname(acpi_handle target_handle,
216 struct acpi_buffer * buffer)
217{
218 acpi_status status;
219 struct acpi_namespace_node *node;
220 acpi_size required_size;
221
222 ACPI_FUNCTION_TRACE_PTR("ns_handle_to_pathname", target_handle);
223
224 node = acpi_ns_map_handle_to_node(target_handle);
225 if (!node) {
226 return_ACPI_STATUS(AE_BAD_PARAMETER);
227 }
228
229 /* Determine size required for the caller buffer */
230
231 required_size = acpi_ns_get_pathname_length(node);
232
233 /* Validate/Allocate/Clear caller buffer */
234
235 status = acpi_ut_initialize_buffer(buffer, required_size);
236 if (ACPI_FAILURE(status)) {
237 return_ACPI_STATUS(status);
238 }
239
240 /* Build the path in the caller buffer */
241
242 acpi_ns_build_external_path(node, required_size, buffer->pointer);
243
244 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "%s [%X] \n",
245 (char *)buffer->pointer, (u32) required_size));
246 return_ACPI_STATUS(AE_OK);
247}