1 /*******************************************************************************
3 * Module Name: nsnames - Name manipulation and search
5 ******************************************************************************/
8 * Copyright (C) 2000 - 2015, Intel Corp.
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
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.
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.
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.
44 #include <acpi/acpi.h>
49 #define _COMPONENT ACPI_NAMESPACE
50 ACPI_MODULE_NAME("nsnames")
52 /*******************************************************************************
54 * FUNCTION: acpi_ns_build_external_path
56 * PARAMETERS: node - NS node whose pathname is needed
57 * size - Size of the pathname
58 * *name_buffer - Where to return the pathname
61 * Places the pathname into the name_buffer, in external format
62 * (name segments separated by path separators)
64 * DESCRIPTION: Generate a full pathaname
66 ******************************************************************************/
68 acpi_ns_build_external_path(struct acpi_namespace_node
*node
,
69 acpi_size size
, char *name_buffer
)
72 struct acpi_namespace_node
*parent_node
;
74 ACPI_FUNCTION_ENTRY();
76 /* Special case for root */
79 if (index
< ACPI_NAME_SIZE
) {
80 name_buffer
[0] = AML_ROOT_PREFIX
;
85 /* Store terminator byte, then build name backwards */
88 name_buffer
[index
] = 0;
90 while ((index
> ACPI_NAME_SIZE
) && (parent_node
!= acpi_gbl_root_node
)) {
91 index
-= ACPI_NAME_SIZE
;
93 /* Put the name into the buffer */
95 ACPI_MOVE_32_TO_32((name_buffer
+ index
), &parent_node
->name
);
96 parent_node
= parent_node
->parent
;
98 /* Prefix name with the path separator */
101 name_buffer
[index
] = ACPI_PATH_SEPARATOR
;
104 /* Overwrite final separator with the root prefix character */
106 name_buffer
[index
] = AML_ROOT_PREFIX
;
110 "Could not construct external pathname; index=%u, size=%u, Path=%s",
111 (u32
) index
, (u32
) size
, &name_buffer
[size
]));
113 return (AE_BAD_PARAMETER
);
119 /*******************************************************************************
121 * FUNCTION: acpi_ns_get_external_pathname
123 * PARAMETERS: node - Namespace node whose pathname is needed
125 * RETURN: Pointer to storage containing the fully qualified name of
126 * the node, In external format (name segments separated by path
129 * DESCRIPTION: Used to obtain the full pathname to a namespace node, usually
130 * for error and debug statements.
132 ******************************************************************************/
134 char *acpi_ns_get_external_pathname(struct acpi_namespace_node
*node
)
140 ACPI_FUNCTION_TRACE_PTR(ns_get_external_pathname
, node
);
142 /* Calculate required buffer size based on depth below root */
144 size
= acpi_ns_get_pathname_length(node
);
149 /* Allocate a buffer to be returned to caller */
151 name_buffer
= ACPI_ALLOCATE_ZEROED(size
);
153 ACPI_ERROR((AE_INFO
, "Could not allocate %u bytes", (u32
)size
));
157 /* Build the path in the allocated buffer */
159 status
= acpi_ns_build_external_path(node
, size
, name_buffer
);
160 if (ACPI_FAILURE(status
)) {
161 ACPI_FREE(name_buffer
);
165 return_PTR(name_buffer
);
168 /*******************************************************************************
170 * FUNCTION: acpi_ns_get_pathname_length
172 * PARAMETERS: node - Namespace node
174 * RETURN: Length of path, including prefix
176 * DESCRIPTION: Get the length of the pathname string for this node
178 ******************************************************************************/
180 acpi_size
acpi_ns_get_pathname_length(struct acpi_namespace_node
*node
)
183 struct acpi_namespace_node
*next_node
;
185 ACPI_FUNCTION_ENTRY();
188 * Compute length of pathname as 5 * number of name segments.
189 * Go back up the parent tree to the root
194 while (next_node
&& (next_node
!= acpi_gbl_root_node
)) {
195 if (ACPI_GET_DESCRIPTOR_TYPE(next_node
) != ACPI_DESC_TYPE_NAMED
) {
197 "Invalid Namespace Node (%p) while traversing namespace",
201 size
+= ACPI_PATH_SEGMENT_LENGTH
;
202 next_node
= next_node
->parent
;
206 size
= 1; /* Root node case */
209 return (size
+ 1); /* +1 for null string terminator */
212 /*******************************************************************************
214 * FUNCTION: acpi_ns_handle_to_pathname
216 * PARAMETERS: target_handle - Handle of named object whose name is
218 * buffer - Where the pathname is returned
220 * RETURN: Status, Buffer is filled with pathname if status is AE_OK
222 * DESCRIPTION: Build and return a full namespace pathname
224 ******************************************************************************/
227 acpi_ns_handle_to_pathname(acpi_handle target_handle
,
228 struct acpi_buffer
* buffer
)
231 struct acpi_namespace_node
*node
;
232 acpi_size required_size
;
234 ACPI_FUNCTION_TRACE_PTR(ns_handle_to_pathname
, target_handle
);
236 node
= acpi_ns_validate_handle(target_handle
);
238 return_ACPI_STATUS(AE_BAD_PARAMETER
);
241 /* Determine size required for the caller buffer */
243 required_size
= acpi_ns_get_pathname_length(node
);
244 if (!required_size
) {
245 return_ACPI_STATUS(AE_BAD_PARAMETER
);
248 /* Validate/Allocate/Clear caller buffer */
250 status
= acpi_ut_initialize_buffer(buffer
, required_size
);
251 if (ACPI_FAILURE(status
)) {
252 return_ACPI_STATUS(status
);
255 /* Build the path in the caller buffer */
258 acpi_ns_build_external_path(node
, required_size
, buffer
->pointer
);
259 if (ACPI_FAILURE(status
)) {
260 return_ACPI_STATUS(status
);
263 ACPI_DEBUG_PRINT((ACPI_DB_EXEC
, "%s [%X]\n",
264 (char *)buffer
->pointer
, (u32
) required_size
));
265 return_ACPI_STATUS(AE_OK
);