1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /*******************************************************************************
3 *
4 * Module Name: nsnames - Name manipulation and search
5 *
6 ******************************************************************************/
7
8 #include <acpi/acpi.h>
9 #include "accommon.h"
10 #include "amlcode.h"
11 #include "acnamesp.h"
12
13 #define _COMPONENT ACPI_NAMESPACE
14 ACPI_MODULE_NAME("nsnames")
15
16 /*******************************************************************************
17 *
18 * FUNCTION: acpi_ns_get_external_pathname
19 *
20 * PARAMETERS: node - Namespace node whose pathname is needed
21 *
22 * RETURN: Pointer to storage containing the fully qualified name of
23 * the node, In external format (name segments separated by path
24 * separators.)
25 *
26 * DESCRIPTION: Used to obtain the full pathname to a namespace node, usually
27 * for error and debug statements.
28 *
29 ******************************************************************************/
30 char *acpi_ns_get_external_pathname(struct acpi_namespace_node *node)
31 {
32 char *name_buffer;
33
34 ACPI_FUNCTION_TRACE_PTR(ns_get_external_pathname, node);
35
36 name_buffer = acpi_ns_get_normalized_pathname(node, FALSE);
37 return_PTR(name_buffer);
38 }
39
40 /*******************************************************************************
41 *
42 * FUNCTION: acpi_ns_get_pathname_length
43 *
44 * PARAMETERS: node - Namespace node
45 *
46 * RETURN: Length of path, including prefix
47 *
48 * DESCRIPTION: Get the length of the pathname string for this node
49 *
50 ******************************************************************************/
51
52 acpi_size acpi_ns_get_pathname_length(struct acpi_namespace_node *node)
53 {
54 acpi_size size;
55
56 /* Validate the Node */
57
58 if (ACPI_GET_DESCRIPTOR_TYPE(node) != ACPI_DESC_TYPE_NAMED) {
59 ACPI_ERROR((AE_INFO,
60 "Invalid/cached reference target node: %p, descriptor type %d",
61 node, ACPI_GET_DESCRIPTOR_TYPE(node)));
62 return (0);
63 }
64
65 size = acpi_ns_build_normalized_path(node, NULL, 0, FALSE);
66 return (size);
67 }
68
69 /*******************************************************************************
70 *
71 * FUNCTION: acpi_ns_handle_to_name
72 *
73 * PARAMETERS: target_handle - Handle of named object whose name is
74 * to be found
75 * buffer - Where the name is returned
76 *
77 * RETURN: Status, Buffer is filled with name if status is AE_OK
78 *
79 * DESCRIPTION: Build and return a full namespace name
80 *
81 ******************************************************************************/
82
83 acpi_status
84 acpi_ns_handle_to_name(acpi_handle target_handle, struct acpi_buffer *buffer)
85 {
86 acpi_status status;
87 struct acpi_namespace_node *node;
88 const char *node_name;
89
90 ACPI_FUNCTION_TRACE_PTR(ns_handle_to_name, target_handle);
91
92 node = acpi_ns_validate_handle(target_handle);
93 if (!node) {
94 return_ACPI_STATUS(AE_BAD_PARAMETER);
95 }
96
97 /* Validate/Allocate/Clear caller buffer */
98
99 status = acpi_ut_initialize_buffer(buffer, ACPI_PATH_SEGMENT_LENGTH);
100 if (ACPI_FAILURE(status)) {
101 return_ACPI_STATUS(status);
102 }
103
104 /* Just copy the ACPI name from the Node and zero terminate it */
105
106 node_name = acpi_ut_get_node_name(node);
107 ACPI_COPY_NAMESEG(buffer->pointer, node_name);
108 ((char *)buffer->pointer)[ACPI_NAMESEG_SIZE] = 0;
109
110 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "%4.4s\n", (char *)buffer->pointer));
111 return_ACPI_STATUS(AE_OK);
112 }
113
114 /*******************************************************************************
115 *
116 * FUNCTION: acpi_ns_handle_to_pathname
117 *
118 * PARAMETERS: target_handle - Handle of named object whose name is
119 * to be found
120 * buffer - Where the pathname is returned
121 * no_trailing - Remove trailing '_' for each name
122 * segment
123 *
124 * RETURN: Status, Buffer is filled with pathname if status is AE_OK
125 *
126 * DESCRIPTION: Build and return a full namespace pathname
127 *
128 ******************************************************************************/
129
130 acpi_status
131 acpi_ns_handle_to_pathname(acpi_handle target_handle,
132 struct acpi_buffer *buffer, u8 no_trailing)
133 {
134 acpi_status status;
135 struct acpi_namespace_node *node;
136 acpi_size required_size;
137
138 ACPI_FUNCTION_TRACE_PTR(ns_handle_to_pathname, target_handle);
139
140 node = acpi_ns_validate_handle(target_handle);
141 if (!node) {
142 return_ACPI_STATUS(AE_BAD_PARAMETER);
143 }
144
145 /* Determine size required for the caller buffer */
146
147 required_size =
148 acpi_ns_build_normalized_path(node, NULL, 0, no_trailing);
149 if (!required_size) {
150 return_ACPI_STATUS(AE_BAD_PARAMETER);
151 }
152
153 /* Validate/Allocate/Clear caller buffer */
154
155 status = acpi_ut_initialize_buffer(buffer, required_size);
156 if (ACPI_FAILURE(status)) {
157 return_ACPI_STATUS(status);
158 }
159
160 /* Build the path in the caller buffer */
161
162 (void)acpi_ns_build_normalized_path(node, buffer->pointer,
163 required_size, no_trailing);
164
165 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "%s [%X]\n",
166 (char *)buffer->pointer, (u32) required_size));
167 return_ACPI_STATUS(AE_OK);
168 }
169
170 /*******************************************************************************
171 *
172 * FUNCTION: acpi_ns_build_normalized_path
173 *
174 * PARAMETERS: node - Namespace node
175 * full_path - Where the path name is returned
176 * path_size - Size of returned path name buffer
177 * no_trailing - Remove trailing '_' from each name segment
178 *
179 * RETURN: Return 1 if the AML path is empty, otherwise returning (length
180 * of pathname + 1) which means the 'FullPath' contains a trailing
181 * null.
182 *
183 * DESCRIPTION: Build and return a full namespace pathname.
184 * Note that if the size of 'FullPath' isn't large enough to
185 * contain the namespace node's path name, the actual required
186 * buffer length is returned, and it should be greater than
187 * 'PathSize'. So callers are able to check the returning value
188 * to determine the buffer size of 'FullPath'.
189 *
190 ******************************************************************************/
191
192 u32
193 acpi_ns_build_normalized_path(struct acpi_namespace_node *node,
194 char *full_path, u32 path_size, u8 no_trailing)
195 {
196 u32 length = 0, i;
197 char name[ACPI_NAMESEG_SIZE];
198 u8 do_no_trailing;
199 char c, *left, *right;
200 struct acpi_namespace_node *next_node;
201
202 ACPI_FUNCTION_TRACE_PTR(ns_build_normalized_path, node);
203
204 #define ACPI_PATH_PUT8(path, size, byte, length) \
205 do { \
206 if ((length) < (size)) \
207 { \
208 (path)[(length)] = (byte); \
209 } \
210 (length)++; \
211 } while (0)
212
213 /*
214 * Make sure the path_size is correct, so that we don't need to
215 * validate both full_path and path_size.
216 */
217 if (!full_path) {
218 path_size = 0;
219 }
220
221 if (!node) {
222 goto build_trailing_null;
223 }
224
225 next_node = node;
226 while (next_node && next_node != acpi_gbl_root_node) {
227 if (next_node != node) {
228 ACPI_PATH_PUT8(full_path, path_size,
229 AML_DUAL_NAME_PREFIX, length);
230 }
231
232 ACPI_MOVE_32_TO_32(name, &next_node->name);
233 do_no_trailing = no_trailing;
234 for (i = 0; i < 4; i++) {
235 c = name[4 - i - 1];
236 if (do_no_trailing && c != '_') {
237 do_no_trailing = FALSE;
238 }
239 if (!do_no_trailing) {
240 ACPI_PATH_PUT8(full_path, path_size, c, length);
241 }
242 }
243
244 next_node = next_node->parent;
245 }
246
247 ACPI_PATH_PUT8(full_path, path_size, AML_ROOT_PREFIX, length);
248
249 /* Reverse the path string */
250
251 if (length <= path_size) {
252 left = full_path;
253 right = full_path + length - 1;
254
255 while (left < right) {
256 c = *left;
257 *left++ = *right;
258 *right-- = c;
259 }
260 }
261
262 /* Append the trailing null */
263
264 build_trailing_null:
265 ACPI_PATH_PUT8(full_path, path_size, '\0', length);
266
267 #undef ACPI_PATH_PUT8
268
269 return_UINT32(length);
270 }
271
272 /*******************************************************************************
273 *
274 * FUNCTION: acpi_ns_get_normalized_pathname
275 *
276 * PARAMETERS: node - Namespace node whose pathname is needed
277 * no_trailing - Remove trailing '_' from each name segment
278 *
279 * RETURN: Pointer to storage containing the fully qualified name of
280 * the node, In external format (name segments separated by path
281 * separators.)
282 *
283 * DESCRIPTION: Used to obtain the full pathname to a namespace node, usually
284 * for error and debug statements. All trailing '_' will be
285 * removed from the full pathname if 'NoTrailing' is specified..
286 *
287 ******************************************************************************/
288
289 char *acpi_ns_get_normalized_pathname(struct acpi_namespace_node *node,
290 u8 no_trailing)
291 {
292 char *name_buffer;
293 acpi_size size;
294
295 ACPI_FUNCTION_TRACE_PTR(ns_get_normalized_pathname, node);
296
297 /* Calculate required buffer size based on depth below root */
298
299 size = acpi_ns_build_normalized_path(node, NULL, 0, no_trailing);
300 if (!size) {
301 return_PTR(NULL);
302 }
303
304 /* Allocate a buffer to be returned to caller */
305
306 name_buffer = ACPI_ALLOCATE_ZEROED(size);
307 if (!name_buffer) {
308 ACPI_ERROR((AE_INFO, "Could not allocate %u bytes", (u32)size));
309 return_PTR(NULL);
310 }
311
312 /* Build the path in the allocated buffer */
313
314 (void)acpi_ns_build_normalized_path(node, name_buffer, size,
315 no_trailing);
316
317 ACPI_DEBUG_PRINT_RAW((ACPI_DB_NAMES, "%s: Path \"%s\"\n",
318 ACPI_GET_FUNCTION_NAME, name_buffer));
319
320 return_PTR(name_buffer);
321 }
322
323 /*******************************************************************************
324 *
325 * FUNCTION: acpi_ns_build_prefixed_pathname
326 *
327 * PARAMETERS: prefix_scope - Scope/Path that prefixes the internal path
328 * internal_path - Name or path of the namespace node
329 *
330 * RETURN: None
331 *
332 * DESCRIPTION: Construct a fully qualified pathname from a concatenation of:
333 * 1) Path associated with the prefix_scope namespace node
334 * 2) External path representation of the Internal path
335 *
336 ******************************************************************************/
337
338 char *acpi_ns_build_prefixed_pathname(union acpi_generic_state *prefix_scope,
339 const char *internal_path)
340 {
341 acpi_status status;
342 char *full_path = NULL;
343 char *external_path = NULL;
344 char *prefix_path = NULL;
345 u32 prefix_path_length = 0;
346
347 /* If there is a prefix, get the pathname to it */
348
349 if (prefix_scope && prefix_scope->scope.node) {
350 prefix_path =
351 acpi_ns_get_normalized_pathname(prefix_scope->scope.node,
352 TRUE);
353 if (prefix_path) {
354 prefix_path_length = strlen(prefix_path);
355 }
356 }
357
358 status = acpi_ns_externalize_name(ACPI_UINT32_MAX, internal_path,
359 NULL, &external_path);
360 if (ACPI_FAILURE(status)) {
361 goto cleanup;
362 }
363
364 /* Merge the prefix path and the path. 2 is for one dot and trailing null */
365
366 full_path =
367 ACPI_ALLOCATE_ZEROED(prefix_path_length + strlen(external_path) +
368 2);
369 if (!full_path) {
370 goto cleanup;
371 }
372
373 /* Don't merge if the External path is already fully qualified */
374
375 if (prefix_path && (*external_path != '\\') && (*external_path != '^')) {
376 strcat(full_path, prefix_path);
377 if (prefix_path[1]) {
378 strcat(full_path, ".");
379 }
380 }
381
382 acpi_ns_normalize_pathname(external_path);
383 strcat(full_path, external_path);
384
385 cleanup:
386 if (prefix_path) {
387 ACPI_FREE(prefix_path);
388 }
389 if (external_path) {
390 ACPI_FREE(external_path);
391 }
392
393 return (full_path);
394 }
395
396 /*******************************************************************************
397 *
398 * FUNCTION: acpi_ns_normalize_pathname
399 *
400 * PARAMETERS: original_path - Path to be normalized, in External format
401 *
402 * RETURN: The original path is processed in-place
403 *
404 * DESCRIPTION: Remove trailing underscores from each element of a path.
405 *
406 * For example: \A___.B___.C___ becomes \A.B.C
407 *
408 ******************************************************************************/
409
410 void acpi_ns_normalize_pathname(char *original_path)
411 {
412 char *input_path = original_path;
413 char *new_path_buffer;
414 char *new_path;
415 u32 i;
416
417 /* Allocate a temp buffer in which to construct the new path */
418
419 new_path_buffer = ACPI_ALLOCATE_ZEROED(strlen(input_path) + 1);
420 new_path = new_path_buffer;
421 if (!new_path_buffer) {
422 return;
423 }
424
425 /* Special characters may appear at the beginning of the path */
426
427 if (*input_path == '\\') {
428 *new_path = *input_path;
429 new_path++;
430 input_path++;
431 }
432
433 while (*input_path == '^') {
434 *new_path = *input_path;
435 new_path++;
436 input_path++;
437 }
438
439 /* Remainder of the path */
440
441 while (*input_path) {
442
443 /* Do one nameseg at a time */
444
445 for (i = 0; (i < ACPI_NAMESEG_SIZE) && *input_path; i++) {
446 if ((i == 0) || (*input_path != '_')) { /* First char is allowed to be underscore */
447 *new_path = *input_path;
448 new_path++;
449 }
450
451 input_path++;
452 }
453
454 /* Dot means that there are more namesegs to come */
455
456 if (*input_path == '.') {
457 *new_path = *input_path;
458 new_path++;
459 input_path++;
460 }
461 }
462
463 *new_path = 0;
464 strcpy(original_path, new_path_buffer);
465 ACPI_FREE(new_path_buffer);
466 }