1 /*******************************************************************************
2 *
3 * Module Name: nsnames - Name manipulation and search
4 *
5 ******************************************************************************/
6
7 /*
8 * Copyright (C) 2000 - 2014, Intel Corp.
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 #define __NSNAMES_C__
45
46 #include "acpi.h"
47 #include "accommon.h"
48 #include "amlcode.h"
49 #include "acnamesp.h"
50
51
52 #define _COMPONENT ACPI_NAMESPACE
53 ACPI_MODULE_NAME ("nsnames")
54
55
56 /*******************************************************************************
57 *
58 * FUNCTION: AcpiNsBuildExternalPath
59 *
60 * PARAMETERS: Node - NS node whose pathname is needed
61 * Size - Size of the pathname
62 * *NameBuffer - Where to return the pathname
63 *
64 * RETURN: Status
65 * Places the pathname into the NameBuffer, in external format
66 * (name segments separated by path separators)
67 *
68 * DESCRIPTION: Generate a full pathaname
69 *
70 ******************************************************************************/
71
72 ACPI_STATUS
73 AcpiNsBuildExternalPath (
74 ACPI_NAMESPACE_NODE *Node,
75 ACPI_SIZE Size,
76 char *NameBuffer)
77 {
78 ACPI_SIZE Index;
79 ACPI_NAMESPACE_NODE *ParentNode;
80
81
82 ACPI_FUNCTION_ENTRY ();
83
84
85 /* Special case for root */
86
87 Index = Size - 1;
88 if (Index < ACPI_NAME_SIZE)
89 {
90 NameBuffer[0] = AML_ROOT_PREFIX;
91 NameBuffer[1] = 0;
92 return (AE_OK);
93 }
94
95 /* Store terminator byte, then build name backwards */
96
97 ParentNode = Node;
98 NameBuffer[Index] = 0;
99
100 while ((Index > ACPI_NAME_SIZE) && (ParentNode != AcpiGbl_RootNode))
101 {
102 Index -= ACPI_NAME_SIZE;
103
104 /* Put the name into the buffer */
105
106 ACPI_MOVE_32_TO_32 ((NameBuffer + Index), &ParentNode->Name);
107 ParentNode = ParentNode->Parent;
108
109 /* Prefix name with the path separator */
110
111 Index--;
112 NameBuffer[Index] = ACPI_PATH_SEPARATOR;
113 }
114
115 /* Overwrite final separator with the root prefix character */
116
117 NameBuffer[Index] = AML_ROOT_PREFIX;
118
119 if (Index != 0)
120 {
121 ACPI_ERROR ((AE_INFO,
122 "Could not construct external pathname; index=%u, size=%u, Path=%s",
123 (UINT32) Index, (UINT32) Size, &NameBuffer[Size]));
124
125 return (AE_BAD_PARAMETER);
126 }
127
128 return (AE_OK);
129 }
130
131
132 /*******************************************************************************
133 *
134 * FUNCTION: AcpiNsGetExternalPathname
135 *
136 * PARAMETERS: Node - Namespace node whose pathname is needed
137 *
138 * RETURN: Pointer to storage containing the fully qualified name of
139 * the node, In external format (name segments separated by path
140 * separators.)
141 *
142 * DESCRIPTION: Used to obtain the full pathname to a namespace node, usually
143 * for error and debug statements.
144 *
145 ******************************************************************************/
146
147 char *
148 AcpiNsGetExternalPathname (
149 ACPI_NAMESPACE_NODE *Node)
150 {
151 ACPI_STATUS Status;
152 char *NameBuffer;
153 ACPI_SIZE Size;
154
155
156 ACPI_FUNCTION_TRACE_PTR (NsGetExternalPathname, Node);
157
158
159 /* Calculate required buffer size based on depth below root */
160
161 Size = AcpiNsGetPathnameLength (Node);
162 if (!Size)
163 {
164 return_PTR (NULL);
165 }
166
167 /* Allocate a buffer to be returned to caller */
168
169 NameBuffer = ACPI_ALLOCATE_ZEROED (Size);
170 if (!NameBuffer)
171 {
172 ACPI_ERROR ((AE_INFO, "Could not allocate %u bytes", (UINT32) Size));
173 return_PTR (NULL);
174 }
175
176 /* Build the path in the allocated buffer */
177
178 Status = AcpiNsBuildExternalPath (Node, Size, NameBuffer);
179 if (ACPI_FAILURE (Status))
180 {
181 ACPI_FREE (NameBuffer);
182 return_PTR (NULL);
183 }
184
185 return_PTR (NameBuffer);
186 }
187
188
189 /*******************************************************************************
190 *
191 * FUNCTION: AcpiNsGetPathnameLength
192 *
193 * PARAMETERS: Node - Namespace node
194 *
195 * RETURN: Length of path, including prefix
196 *
197 * DESCRIPTION: Get the length of the pathname string for this node
198 *
199 ******************************************************************************/
200
201 ACPI_SIZE
202 AcpiNsGetPathnameLength (
203 ACPI_NAMESPACE_NODE *Node)
204 {
205 ACPI_SIZE Size;
206 ACPI_NAMESPACE_NODE *NextNode;
207
208
209 ACPI_FUNCTION_ENTRY ();
210
211
212 /*
213 * Compute length of pathname as 5 * number of name segments.
214 * Go back up the parent tree to the root
215 */
216 Size = 0;
217 NextNode = Node;
218
219 while (NextNode && (NextNode != AcpiGbl_RootNode))
220 {
221 if (ACPI_GET_DESCRIPTOR_TYPE (NextNode) != ACPI_DESC_TYPE_NAMED)
222 {
223 ACPI_ERROR ((AE_INFO,
224 "Invalid Namespace Node (%p) while traversing namespace",
225 NextNode));
226 return (0);
227 }
228 Size += ACPI_PATH_SEGMENT_LENGTH;
229 NextNode = NextNode->Parent;
230 }
231
232 if (!Size)
233 {
234 Size = 1; /* Root node case */
235 }
236
237 return (Size + 1); /* +1 for null string terminator */
238 }
239
240
241 /*******************************************************************************
242 *
243 * FUNCTION: AcpiNsHandleToPathname
244 *
245 * PARAMETERS: TargetHandle - Handle of named object whose name is
246 * to be found
247 * Buffer - Where the pathname is returned
248 *
249 * RETURN: Status, Buffer is filled with pathname if status is AE_OK
250 *
251 * DESCRIPTION: Build and return a full namespace pathname
252 *
253 ******************************************************************************/
254
255 ACPI_STATUS
256 AcpiNsHandleToPathname (
257 ACPI_HANDLE TargetHandle,
258 ACPI_BUFFER *Buffer)
259 {
260 ACPI_STATUS Status;
261 ACPI_NAMESPACE_NODE *Node;
262 ACPI_SIZE RequiredSize;
263
264
265 ACPI_FUNCTION_TRACE_PTR (NsHandleToPathname, TargetHandle);
266
267
268 Node = AcpiNsValidateHandle (TargetHandle);
269 if (!Node)
270 {
271 return_ACPI_STATUS (AE_BAD_PARAMETER);
272 }
273
274 /* Determine size required for the caller buffer */
275
276 RequiredSize = AcpiNsGetPathnameLength (Node);
277 if (!RequiredSize)
278 {
279 return_ACPI_STATUS (AE_BAD_PARAMETER);
280 }
281
282 /* Validate/Allocate/Clear caller buffer */
283
284 Status = AcpiUtInitializeBuffer (Buffer, RequiredSize);
285 if (ACPI_FAILURE (Status))
286 {
287 return_ACPI_STATUS (Status);
288 }
289
290 /* Build the path in the caller buffer */
291
292 Status = AcpiNsBuildExternalPath (Node, RequiredSize, Buffer->Pointer);
293 if (ACPI_FAILURE (Status))
294 {
295 return_ACPI_STATUS (Status);
296 }
297
298 ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "%s [%X]\n",
299 (char *) Buffer->Pointer, (UINT32) RequiredSize));
300 return_ACPI_STATUS (AE_OK);
301 }