1 /******************************************************************************
2 *
3 * Module Name: exnames - interpreter/scanner name load/execute
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 #include "acpi.h"
45 #include "accommon.h"
46 #include "acinterp.h"
47 #include "amlcode.h"
48
49 #define _COMPONENT ACPI_EXECUTER
50 ACPI_MODULE_NAME ("exnames")
51
52 /* Local prototypes */
53
54 static char *
55 AcpiExAllocateNameString (
56 UINT32 PrefixCount,
57 UINT32 NumNameSegs);
58
59 static ACPI_STATUS
60 AcpiExNameSegment (
61 UINT8 **InAmlAddress,
62 char *NameString);
63
64
65 /*******************************************************************************
66 *
67 * FUNCTION: AcpiExAllocateNameString
68 *
69 * PARAMETERS: PrefixCount - Count of parent levels. Special cases:
70 * (-1)==root, 0==none
71 * NumNameSegs - count of 4-character name segments
72 *
73 * RETURN: A pointer to the allocated string segment. This segment must
74 * be deleted by the caller.
75 *
76 * DESCRIPTION: Allocate a buffer for a name string. Ensure allocated name
77 * string is long enough, and set up prefix if any.
78 *
79 ******************************************************************************/
80
81 static char *
AcpiExAllocateNameString(UINT32 PrefixCount,UINT32 NumNameSegs)82 AcpiExAllocateNameString (
83 UINT32 PrefixCount,
84 UINT32 NumNameSegs)
85 {
86 char *TempPtr;
87 char *NameString;
88 UINT32 SizeNeeded;
89
90 ACPI_FUNCTION_TRACE (ExAllocateNameString);
91
92
93 /*
94 * Allow room for all \ and ^ prefixes, all segments and a MultiNamePrefix.
95 * Also, one byte for the null terminator.
96 * This may actually be somewhat longer than needed.
97 */
98 if (PrefixCount == ACPI_UINT32_MAX)
99 {
100 /* Special case for root */
101
102 SizeNeeded = 1 + (ACPI_NAME_SIZE * NumNameSegs) + 2 + 1;
103 }
104 else
105 {
106 SizeNeeded = PrefixCount + (ACPI_NAME_SIZE * NumNameSegs) + 2 + 1;
107 }
108
109 /*
110 * Allocate a buffer for the name.
111 * This buffer must be deleted by the caller!
112 */
113 NameString = ACPI_ALLOCATE (SizeNeeded);
114 if (!NameString)
115 {
116 ACPI_ERROR ((AE_INFO,
117 "Could not allocate size %u", SizeNeeded));
118 return_PTR (NULL);
119 }
120
121 TempPtr = NameString;
122
123 /* Set up Root or Parent prefixes if needed */
124
125 if (PrefixCount == ACPI_UINT32_MAX)
126 {
127 *TempPtr++ = AML_ROOT_PREFIX;
128 }
129 else
130 {
131 while (PrefixCount--)
132 {
133 *TempPtr++ = AML_PARENT_PREFIX;
134 }
135 }
136
137
138 /* Set up Dual or Multi prefixes if needed */
139
140 if (NumNameSegs > 2)
141 {
142 /* Set up multi prefixes */
143
144 *TempPtr++ = AML_MULTI_NAME_PREFIX_OP;
145 *TempPtr++ = (char) NumNameSegs;
146 }
147 else if (2 == NumNameSegs)
148 {
149 /* Set up dual prefixes */
150
151 *TempPtr++ = AML_DUAL_NAME_PREFIX;
152 }
153
154 /*
155 * Terminate string following prefixes. AcpiExNameSegment() will
156 * append the segment(s)
157 */
158 *TempPtr = 0;
159
160 return_PTR (NameString);
161 }
162
163 /*******************************************************************************
164 *
165 * FUNCTION: AcpiExNameSegment
166 *
167 * PARAMETERS: InAmlAddress - Pointer to the name in the AML code
168 * NameString - Where to return the name. The name is appended
169 * to any existing string to form a namepath
170 *
171 * RETURN: Status
172 *
173 * DESCRIPTION: Extract an ACPI name (4 bytes) from the AML byte stream
174 *
175 ******************************************************************************/
176
177 static ACPI_STATUS
AcpiExNameSegment(UINT8 ** InAmlAddress,char * NameString)178 AcpiExNameSegment (
179 UINT8 **InAmlAddress,
180 char *NameString)
181 {
182 char *AmlAddress = (void *) *InAmlAddress;
183 ACPI_STATUS Status = AE_OK;
184 UINT32 Index;
185 char CharBuf[5];
186
187
188 ACPI_FUNCTION_TRACE (ExNameSegment);
189
190
191 /*
192 * If first character is a digit, then we know that we aren't looking at a
193 * valid name segment
194 */
195 CharBuf[0] = *AmlAddress;
196
197 if ('0' <= CharBuf[0] && CharBuf[0] <= '9')
198 {
199 ACPI_ERROR ((AE_INFO, "Invalid leading digit: %c", CharBuf[0]));
200 return_ACPI_STATUS (AE_CTRL_PENDING);
201 }
202
203 ACPI_DEBUG_PRINT ((ACPI_DB_LOAD, "Bytes from stream:\n"));
204
205 for (Index = 0;
206 (Index < ACPI_NAME_SIZE) && (AcpiUtValidAcpiChar (*AmlAddress, 0));
207 Index++)
208 {
209 CharBuf[Index] = *AmlAddress++;
210 ACPI_DEBUG_PRINT ((ACPI_DB_LOAD, "%c\n", CharBuf[Index]));
211 }
212
213
214 /* Valid name segment */
215
216 if (Index == 4)
217 {
218 /* Found 4 valid characters */
219
220 CharBuf[4] = '\0';
221
222 if (NameString)
223 {
224 ACPI_STRCAT (NameString, CharBuf);
225 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
226 "Appended to - %s\n", NameString));
227 }
228 else
229 {
230 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
231 "No Name string - %s\n", CharBuf));
232 }
233 }
234 else if (Index == 0)
235 {
236 /*
237 * First character was not a valid name character,
238 * so we are looking at something other than a name.
239 */
240 ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
241 "Leading character is not alpha: %02Xh (not a name)\n",
242 CharBuf[0]));
243 Status = AE_CTRL_PENDING;
244 }
245 else
246 {
247 /*
248 * Segment started with one or more valid characters, but fewer than
249 * the required 4
250 */
251 Status = AE_AML_BAD_NAME;
252 ACPI_ERROR ((AE_INFO,
253 "Bad character 0x%02x in name, at %p",
254 *AmlAddress, AmlAddress));
255 }
256
257 *InAmlAddress = ACPI_CAST_PTR (UINT8, AmlAddress);
258 return_ACPI_STATUS (Status);
259 }
260
261
262 /*******************************************************************************
263 *
264 * FUNCTION: AcpiExGetNameString
265 *
266 * PARAMETERS: DataType - Object type to be associated with this
267 * name
268 * InAmlAddress - Pointer to the namestring in the AML code
269 * OutNameString - Where the namestring is returned
270 * OutNameLength - Length of the returned string
271 *
272 * RETURN: Status, namestring and length
273 *
274 * DESCRIPTION: Extract a full namepath from the AML byte stream,
275 * including any prefixes.
276 *
277 ******************************************************************************/
278
279 ACPI_STATUS
AcpiExGetNameString(ACPI_OBJECT_TYPE DataType,UINT8 * InAmlAddress,char ** OutNameString,UINT32 * OutNameLength)280 AcpiExGetNameString (
281 ACPI_OBJECT_TYPE DataType,
282 UINT8 *InAmlAddress,
283 char **OutNameString,
284 UINT32 *OutNameLength)
285 {
286 ACPI_STATUS Status = AE_OK;
287 UINT8 *AmlAddress = InAmlAddress;
288 char *NameString = NULL;
289 UINT32 NumSegments;
290 UINT32 PrefixCount = 0;
291 BOOLEAN HasPrefix = FALSE;
292
293
294 ACPI_FUNCTION_TRACE_PTR (ExGetNameString, AmlAddress);
295
296
297 if (ACPI_TYPE_LOCAL_REGION_FIELD == DataType ||
298 ACPI_TYPE_LOCAL_BANK_FIELD == DataType ||
299 ACPI_TYPE_LOCAL_INDEX_FIELD == DataType)
300 {
301 /* Disallow prefixes for types associated with FieldUnit names */
302
303 NameString = AcpiExAllocateNameString (0, 1);
304 if (!NameString)
305 {
306 Status = AE_NO_MEMORY;
307 }
308 else
309 {
310 Status = AcpiExNameSegment (&AmlAddress, NameString);
311 }
312 }
313 else
314 {
315 /*
316 * DataType is not a field name.
317 * Examine first character of name for root or parent prefix operators
318 */
319 switch (*AmlAddress)
320 {
321 case AML_ROOT_PREFIX:
322
323 ACPI_DEBUG_PRINT ((ACPI_DB_LOAD, "RootPrefix(\\) at %p\n",
324 AmlAddress));
325
326 /*
327 * Remember that we have a RootPrefix --
328 * see comment in AcpiExAllocateNameString()
329 */
330 AmlAddress++;
331 PrefixCount = ACPI_UINT32_MAX;
332 HasPrefix = TRUE;
333 break;
334
335 case AML_PARENT_PREFIX:
336
337 /* Increment past possibly multiple parent prefixes */
338
339 do
340 {
341 ACPI_DEBUG_PRINT ((ACPI_DB_LOAD, "ParentPrefix (^) at %p\n",
342 AmlAddress));
343
344 AmlAddress++;
345 PrefixCount++;
346
347 } while (*AmlAddress == AML_PARENT_PREFIX);
348
349 HasPrefix = TRUE;
350 break;
351
352 default:
353
354 /* Not a prefix character */
355
356 break;
357 }
358
359 /* Examine first character of name for name segment prefix operator */
360
361 switch (*AmlAddress)
362 {
363 case AML_DUAL_NAME_PREFIX:
364
365 ACPI_DEBUG_PRINT ((ACPI_DB_LOAD, "DualNamePrefix at %p\n",
366 AmlAddress));
367
368 AmlAddress++;
369 NameString = AcpiExAllocateNameString (PrefixCount, 2);
370 if (!NameString)
371 {
372 Status = AE_NO_MEMORY;
373 break;
374 }
375
376 /* Indicate that we processed a prefix */
377
378 HasPrefix = TRUE;
379
380 Status = AcpiExNameSegment (&AmlAddress, NameString);
381 if (ACPI_SUCCESS (Status))
382 {
383 Status = AcpiExNameSegment (&AmlAddress, NameString);
384 }
385 break;
386
387 case AML_MULTI_NAME_PREFIX_OP:
388
389 ACPI_DEBUG_PRINT ((ACPI_DB_LOAD, "MultiNamePrefix at %p\n",
390 AmlAddress));
391
392 /* Fetch count of segments remaining in name path */
393
394 AmlAddress++;
395 NumSegments = *AmlAddress;
396
397 NameString = AcpiExAllocateNameString (PrefixCount, NumSegments);
398 if (!NameString)
399 {
400 Status = AE_NO_MEMORY;
401 break;
402 }
403
404 /* Indicate that we processed a prefix */
405
406 AmlAddress++;
407 HasPrefix = TRUE;
408
409 while (NumSegments &&
410 (Status = AcpiExNameSegment (&AmlAddress, NameString)) ==
411 AE_OK)
412 {
413 NumSegments--;
414 }
415
416 break;
417
418 case 0:
419
420 /* NullName valid as of 8-12-98 ASL/AML Grammar Update */
421
422 if (PrefixCount == ACPI_UINT32_MAX)
423 {
424 ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
425 "NameSeg is \"\\\" followed by NULL\n"));
426 }
427
428 /* Consume the NULL byte */
429
430 AmlAddress++;
431 NameString = AcpiExAllocateNameString (PrefixCount, 0);
432 if (!NameString)
433 {
434 Status = AE_NO_MEMORY;
435 break;
436 }
437
438 break;
439
440 default:
441
442 /* Name segment string */
443
444 NameString = AcpiExAllocateNameString (PrefixCount, 1);
445 if (!NameString)
446 {
447 Status = AE_NO_MEMORY;
448 break;
449 }
450
451 Status = AcpiExNameSegment (&AmlAddress, NameString);
452 break;
453 }
454 }
455
456 if (AE_CTRL_PENDING == Status && HasPrefix)
457 {
458 /* Ran out of segments after processing a prefix */
459
460 ACPI_ERROR ((AE_INFO,
461 "Malformed Name at %p", NameString));
462 Status = AE_AML_BAD_NAME;
463 }
464
465 if (ACPI_FAILURE (Status))
466 {
467 if (NameString)
468 {
469 ACPI_FREE (NameString);
470 }
471 return_ACPI_STATUS (Status);
472 }
473
474 *OutNameString = NameString;
475 *OutNameLength = (UINT32) (AmlAddress - InAmlAddress);
476
477 return_ACPI_STATUS (Status);
478 }
479