xref: /haiku/src/add-ons/kernel/bus_managers/acpi/acpica/components/namespace/nsutils.c (revision 579f1dbca962a2a03df54f69fdc6e9423f91f20e)
1 /******************************************************************************
2  *
3  * Module Name: nsutils - Utilities for accessing ACPI namespace, accessing
4  *                        parents and siblings and Scope manipulation
5  *
6  *****************************************************************************/
7 
8 /******************************************************************************
9  *
10  * 1. Copyright Notice
11  *
12  * Some or all of this work - Copyright (c) 1999 - 2012, Intel Corp.
13  * All rights reserved.
14  *
15  * 2. License
16  *
17  * 2.1. This is your license from Intel Corp. under its intellectual property
18  * rights. You may have additional license terms from the party that provided
19  * you this software, covering your right to use that party's intellectual
20  * property rights.
21  *
22  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
23  * copy of the source code appearing in this file ("Covered Code") an
24  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
25  * base code distributed originally by Intel ("Original Intel Code") to copy,
26  * make derivatives, distribute, use and display any portion of the Covered
27  * Code in any form, with the right to sublicense such rights; and
28  *
29  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
30  * license (with the right to sublicense), under only those claims of Intel
31  * patents that are infringed by the Original Intel Code, to make, use, sell,
32  * offer to sell, and import the Covered Code and derivative works thereof
33  * solely to the minimum extent necessary to exercise the above copyright
34  * license, and in no event shall the patent license extend to any additions
35  * to or modifications of the Original Intel Code. No other license or right
36  * is granted directly or by implication, estoppel or otherwise;
37  *
38  * The above copyright and patent license is granted only if the following
39  * conditions are met:
40  *
41  * 3. Conditions
42  *
43  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
44  * Redistribution of source code of any substantial portion of the Covered
45  * Code or modification with rights to further distribute source must include
46  * the above Copyright Notice, the above License, this list of Conditions,
47  * and the following Disclaimer and Export Compliance provision. In addition,
48  * Licensee must cause all Covered Code to which Licensee contributes to
49  * contain a file documenting the changes Licensee made to create that Covered
50  * Code and the date of any change. Licensee must include in that file the
51  * documentation of any changes made by any predecessor Licensee. Licensee
52  * must include a prominent statement that the modification is derived,
53  * directly or indirectly, from Original Intel Code.
54  *
55  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
56  * Redistribution of source code of any substantial portion of the Covered
57  * Code or modification without rights to further distribute source must
58  * include the following Disclaimer and Export Compliance provision in the
59  * documentation and/or other materials provided with distribution. In
60  * addition, Licensee may not authorize further sublicense of source of any
61  * portion of the Covered Code, and must include terms to the effect that the
62  * license from Licensee to its licensee is limited to the intellectual
63  * property embodied in the software Licensee provides to its licensee, and
64  * not to intellectual property embodied in modifications its licensee may
65  * make.
66  *
67  * 3.3. Redistribution of Executable. Redistribution in executable form of any
68  * substantial portion of the Covered Code or modification must reproduce the
69  * above Copyright Notice, and the following Disclaimer and Export Compliance
70  * provision in the documentation and/or other materials provided with the
71  * distribution.
72  *
73  * 3.4. Intel retains all right, title, and interest in and to the Original
74  * Intel Code.
75  *
76  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
77  * Intel shall be used in advertising or otherwise to promote the sale, use or
78  * other dealings in products derived from or relating to the Covered Code
79  * without prior written authorization from Intel.
80  *
81  * 4. Disclaimer and Export Compliance
82  *
83  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
84  * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
85  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
86  * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
87  * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
88  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
89  * PARTICULAR PURPOSE.
90  *
91  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
92  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
93  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
94  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
95  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
96  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
97  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
98  * LIMITED REMEDY.
99  *
100  * 4.3. Licensee shall not export, either directly or indirectly, any of this
101  * software or system incorporating such software without first obtaining any
102  * required license or other approval from the U. S. Department of Commerce or
103  * any other agency or department of the United States Government. In the
104  * event Licensee exports any such software from the United States or
105  * re-exports any such software from a foreign destination, Licensee shall
106  * ensure that the distribution and export/re-export of the software is in
107  * compliance with all laws, regulations, orders, or other restrictions of the
108  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
109  * any of its subsidiaries will export/re-export any technical data, process,
110  * software, or service, directly or indirectly, to any country for which the
111  * United States government or any agency thereof requires an export license,
112  * other governmental approval, or letter of assurance, without first obtaining
113  * such license, approval or letter.
114  *
115  *****************************************************************************/
116 
117 #define __NSUTILS_C__
118 
119 #include "acpi.h"
120 #include "accommon.h"
121 #include "acnamesp.h"
122 #include "amlcode.h"
123 
124 #define _COMPONENT          ACPI_NAMESPACE
125         ACPI_MODULE_NAME    ("nsutils")
126 
127 /* Local prototypes */
128 
129 static BOOLEAN
130 AcpiNsValidPathSeparator (
131     char                    Sep);
132 
133 #ifdef ACPI_OBSOLETE_FUNCTIONS
134 ACPI_NAME
135 AcpiNsFindParentName (
136     ACPI_NAMESPACE_NODE     *NodeToSearch);
137 #endif
138 
139 
140 /*******************************************************************************
141  *
142  * FUNCTION:    AcpiNsPrintNodePathname
143  *
144  * PARAMETERS:  Node            - Object
145  *              Message         - Prefix message
146  *
147  * DESCRIPTION: Print an object's full namespace pathname
148  *              Manages allocation/freeing of a pathname buffer
149  *
150  ******************************************************************************/
151 
152 void
153 AcpiNsPrintNodePathname (
154     ACPI_NAMESPACE_NODE     *Node,
155     const char              *Message)
156 {
157     ACPI_BUFFER             Buffer;
158     ACPI_STATUS             Status;
159 
160 
161     if (!Node)
162     {
163         AcpiOsPrintf ("[NULL NAME]");
164         return;
165     }
166 
167     /* Convert handle to full pathname and print it (with supplied message) */
168 
169     Buffer.Length = ACPI_ALLOCATE_LOCAL_BUFFER;
170 
171     Status = AcpiNsHandleToPathname (Node, &Buffer);
172     if (ACPI_SUCCESS (Status))
173     {
174         if (Message)
175         {
176             AcpiOsPrintf ("%s ", Message);
177         }
178 
179         AcpiOsPrintf ("[%s] (Node %p)", (char *) Buffer.Pointer, Node);
180         ACPI_FREE (Buffer.Pointer);
181     }
182 }
183 
184 
185 /*******************************************************************************
186  *
187  * FUNCTION:    AcpiNsValidRootPrefix
188  *
189  * PARAMETERS:  Prefix          - Character to be checked
190  *
191  * RETURN:      TRUE if a valid prefix
192  *
193  * DESCRIPTION: Check if a character is a valid ACPI Root prefix
194  *
195  ******************************************************************************/
196 
197 BOOLEAN
198 AcpiNsValidRootPrefix (
199     char                    Prefix)
200 {
201 
202     return ((BOOLEAN) (Prefix == '\\'));
203 }
204 
205 
206 /*******************************************************************************
207  *
208  * FUNCTION:    AcpiNsValidPathSeparator
209  *
210  * PARAMETERS:  Sep         - Character to be checked
211  *
212  * RETURN:      TRUE if a valid path separator
213  *
214  * DESCRIPTION: Check if a character is a valid ACPI path separator
215  *
216  ******************************************************************************/
217 
218 static BOOLEAN
219 AcpiNsValidPathSeparator (
220     char                    Sep)
221 {
222 
223     return ((BOOLEAN) (Sep == '.'));
224 }
225 
226 
227 /*******************************************************************************
228  *
229  * FUNCTION:    AcpiNsGetType
230  *
231  * PARAMETERS:  Node        - Parent Node to be examined
232  *
233  * RETURN:      Type field from Node whose handle is passed
234  *
235  * DESCRIPTION: Return the type of a Namespace node
236  *
237  ******************************************************************************/
238 
239 ACPI_OBJECT_TYPE
240 AcpiNsGetType (
241     ACPI_NAMESPACE_NODE     *Node)
242 {
243     ACPI_FUNCTION_TRACE (NsGetType);
244 
245 
246     if (!Node)
247     {
248         ACPI_WARNING ((AE_INFO, "Null Node parameter"));
249         return_UINT32 (ACPI_TYPE_ANY);
250     }
251 
252     return_UINT32 ((ACPI_OBJECT_TYPE) Node->Type);
253 }
254 
255 
256 /*******************************************************************************
257  *
258  * FUNCTION:    AcpiNsLocal
259  *
260  * PARAMETERS:  Type        - A namespace object type
261  *
262  * RETURN:      LOCAL if names must be found locally in objects of the
263  *              passed type, 0 if enclosing scopes should be searched
264  *
265  * DESCRIPTION: Returns scope rule for the given object type.
266  *
267  ******************************************************************************/
268 
269 UINT32
270 AcpiNsLocal (
271     ACPI_OBJECT_TYPE        Type)
272 {
273     ACPI_FUNCTION_TRACE (NsLocal);
274 
275 
276     if (!AcpiUtValidObjectType (Type))
277     {
278         /* Type code out of range  */
279 
280         ACPI_WARNING ((AE_INFO, "Invalid Object Type 0x%X", Type));
281         return_UINT32 (ACPI_NS_NORMAL);
282     }
283 
284     return_UINT32 ((UINT32) AcpiGbl_NsProperties[Type] & ACPI_NS_LOCAL);
285 }
286 
287 
288 /*******************************************************************************
289  *
290  * FUNCTION:    AcpiNsGetInternalNameLength
291  *
292  * PARAMETERS:  Info            - Info struct initialized with the
293  *                                external name pointer.
294  *
295  * RETURN:      None
296  *
297  * DESCRIPTION: Calculate the length of the internal (AML) namestring
298  *              corresponding to the external (ASL) namestring.
299  *
300  ******************************************************************************/
301 
302 void
303 AcpiNsGetInternalNameLength (
304     ACPI_NAMESTRING_INFO    *Info)
305 {
306     const char              *NextExternalChar;
307     UINT32                  i;
308 
309 
310     ACPI_FUNCTION_ENTRY ();
311 
312 
313     NextExternalChar = Info->ExternalName;
314     Info->NumCarats = 0;
315     Info->NumSegments = 0;
316     Info->FullyQualified = FALSE;
317 
318     /*
319      * For the internal name, the required length is 4 bytes per segment, plus
320      * 1 each for RootPrefix, MultiNamePrefixOp, segment count, trailing null
321      * (which is not really needed, but no there's harm in putting it there)
322      *
323      * strlen() + 1 covers the first NameSeg, which has no path separator
324      */
325     if (AcpiNsValidRootPrefix (*NextExternalChar))
326     {
327         Info->FullyQualified = TRUE;
328         NextExternalChar++;
329 
330         /* Skip redundant RootPrefix, like \\_SB.PCI0.SBRG.EC0 */
331 
332         while (AcpiNsValidRootPrefix (*NextExternalChar))
333         {
334             NextExternalChar++;
335         }
336     }
337     else
338     {
339         /* Handle Carat prefixes */
340 
341         while (*NextExternalChar == '^')
342         {
343             Info->NumCarats++;
344             NextExternalChar++;
345         }
346     }
347 
348     /*
349      * Determine the number of ACPI name "segments" by counting the number of
350      * path separators within the string. Start with one segment since the
351      * segment count is [(# separators) + 1], and zero separators is ok.
352      */
353     if (*NextExternalChar)
354     {
355         Info->NumSegments = 1;
356         for (i = 0; NextExternalChar[i]; i++)
357         {
358             if (AcpiNsValidPathSeparator (NextExternalChar[i]))
359             {
360                 Info->NumSegments++;
361             }
362         }
363     }
364 
365     Info->Length = (ACPI_NAME_SIZE * Info->NumSegments) +
366                     4 + Info->NumCarats;
367 
368     Info->NextExternalChar = NextExternalChar;
369 }
370 
371 
372 /*******************************************************************************
373  *
374  * FUNCTION:    AcpiNsBuildInternalName
375  *
376  * PARAMETERS:  Info            - Info struct fully initialized
377  *
378  * RETURN:      Status
379  *
380  * DESCRIPTION: Construct the internal (AML) namestring
381  *              corresponding to the external (ASL) namestring.
382  *
383  ******************************************************************************/
384 
385 ACPI_STATUS
386 AcpiNsBuildInternalName (
387     ACPI_NAMESTRING_INFO    *Info)
388 {
389     UINT32                  NumSegments = Info->NumSegments;
390     char                    *InternalName = Info->InternalName;
391     const char              *ExternalName = Info->NextExternalChar;
392     char                    *Result = NULL;
393     UINT32                  i;
394 
395 
396     ACPI_FUNCTION_TRACE (NsBuildInternalName);
397 
398 
399     /* Setup the correct prefixes, counts, and pointers */
400 
401     if (Info->FullyQualified)
402     {
403         InternalName[0] = '\\';
404 
405         if (NumSegments <= 1)
406         {
407             Result = &InternalName[1];
408         }
409         else if (NumSegments == 2)
410         {
411             InternalName[1] = AML_DUAL_NAME_PREFIX;
412             Result = &InternalName[2];
413         }
414         else
415         {
416             InternalName[1] = AML_MULTI_NAME_PREFIX_OP;
417             InternalName[2] = (char) NumSegments;
418             Result = &InternalName[3];
419         }
420     }
421     else
422     {
423         /*
424          * Not fully qualified.
425          * Handle Carats first, then append the name segments
426          */
427         i = 0;
428         if (Info->NumCarats)
429         {
430             for (i = 0; i < Info->NumCarats; i++)
431             {
432                 InternalName[i] = '^';
433             }
434         }
435 
436         if (NumSegments <= 1)
437         {
438             Result = &InternalName[i];
439         }
440         else if (NumSegments == 2)
441         {
442             InternalName[i] = AML_DUAL_NAME_PREFIX;
443             Result = &InternalName[(ACPI_SIZE) i+1];
444         }
445         else
446         {
447             InternalName[i] = AML_MULTI_NAME_PREFIX_OP;
448             InternalName[(ACPI_SIZE) i+1] = (char) NumSegments;
449             Result = &InternalName[(ACPI_SIZE) i+2];
450         }
451     }
452 
453     /* Build the name (minus path separators) */
454 
455     for (; NumSegments; NumSegments--)
456     {
457         for (i = 0; i < ACPI_NAME_SIZE; i++)
458         {
459             if (AcpiNsValidPathSeparator (*ExternalName) ||
460                (*ExternalName == 0))
461             {
462                 /* Pad the segment with underscore(s) if segment is short */
463 
464                 Result[i] = '_';
465             }
466             else
467             {
468                 /* Convert the character to uppercase and save it */
469 
470                 Result[i] = (char) ACPI_TOUPPER ((int) *ExternalName);
471                 ExternalName++;
472             }
473         }
474 
475         /* Now we must have a path separator, or the pathname is bad */
476 
477         if (!AcpiNsValidPathSeparator (*ExternalName) &&
478             (*ExternalName != 0))
479         {
480             return_ACPI_STATUS (AE_BAD_PATHNAME);
481         }
482 
483         /* Move on the next segment */
484 
485         ExternalName++;
486         Result += ACPI_NAME_SIZE;
487     }
488 
489     /* Terminate the string */
490 
491     *Result = 0;
492 
493     if (Info->FullyQualified)
494     {
495         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Returning [%p] (abs) \"\\%s\"\n",
496             InternalName, InternalName));
497     }
498     else
499     {
500         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Returning [%p] (rel) \"%s\"\n",
501             InternalName, InternalName));
502     }
503 
504     return_ACPI_STATUS (AE_OK);
505 }
506 
507 
508 /*******************************************************************************
509  *
510  * FUNCTION:    AcpiNsInternalizeName
511  *
512  * PARAMETERS:  *ExternalName           - External representation of name
513  *              **Converted Name        - Where to return the resulting
514  *                                        internal represention of the name
515  *
516  * RETURN:      Status
517  *
518  * DESCRIPTION: Convert an external representation (e.g. "\_PR_.CPU0")
519  *              to internal form (e.g. 5c 2f 02 5f 50 52 5f 43 50 55 30)
520  *
521  *******************************************************************************/
522 
523 ACPI_STATUS
524 AcpiNsInternalizeName (
525     const char              *ExternalName,
526     char                    **ConvertedName)
527 {
528     char                    *InternalName;
529     ACPI_NAMESTRING_INFO    Info;
530     ACPI_STATUS             Status;
531 
532 
533     ACPI_FUNCTION_TRACE (NsInternalizeName);
534 
535 
536     if ((!ExternalName)      ||
537         (*ExternalName == 0) ||
538         (!ConvertedName))
539     {
540         return_ACPI_STATUS (AE_BAD_PARAMETER);
541     }
542 
543     /* Get the length of the new internal name */
544 
545     Info.ExternalName = ExternalName;
546     AcpiNsGetInternalNameLength (&Info);
547 
548     /* We need a segment to store the internal  name */
549 
550     InternalName = ACPI_ALLOCATE_ZEROED (Info.Length);
551     if (!InternalName)
552     {
553         return_ACPI_STATUS (AE_NO_MEMORY);
554     }
555 
556     /* Build the name */
557 
558     Info.InternalName = InternalName;
559     Status = AcpiNsBuildInternalName (&Info);
560     if (ACPI_FAILURE (Status))
561     {
562         ACPI_FREE (InternalName);
563         return_ACPI_STATUS (Status);
564     }
565 
566     *ConvertedName = InternalName;
567     return_ACPI_STATUS (AE_OK);
568 }
569 
570 
571 /*******************************************************************************
572  *
573  * FUNCTION:    AcpiNsExternalizeName
574  *
575  * PARAMETERS:  InternalNameLength  - Lenth of the internal name below
576  *              InternalName        - Internal representation of name
577  *              ConvertedNameLength - Where the length is returned
578  *              ConvertedName       - Where the resulting external name
579  *                                    is returned
580  *
581  * RETURN:      Status
582  *
583  * DESCRIPTION: Convert internal name (e.g. 5c 2f 02 5f 50 52 5f 43 50 55 30)
584  *              to its external (printable) form (e.g. "\_PR_.CPU0")
585  *
586  ******************************************************************************/
587 
588 ACPI_STATUS
589 AcpiNsExternalizeName (
590     UINT32                  InternalNameLength,
591     const char              *InternalName,
592     UINT32                  *ConvertedNameLength,
593     char                    **ConvertedName)
594 {
595     UINT32                  NamesIndex = 0;
596     UINT32                  NumSegments = 0;
597     UINT32                  RequiredLength;
598     UINT32                  PrefixLength = 0;
599     UINT32                  i = 0;
600     UINT32                  j = 0;
601 
602 
603     ACPI_FUNCTION_TRACE (NsExternalizeName);
604 
605 
606     if (!InternalNameLength     ||
607         !InternalName           ||
608         !ConvertedName)
609     {
610         return_ACPI_STATUS (AE_BAD_PARAMETER);
611     }
612 
613     /* Check for a prefix (one '\' | one or more '^') */
614 
615     switch (InternalName[0])
616     {
617     case '\\':
618         PrefixLength = 1;
619         break;
620 
621     case '^':
622         for (i = 0; i < InternalNameLength; i++)
623         {
624             if (InternalName[i] == '^')
625             {
626                 PrefixLength = i + 1;
627             }
628             else
629             {
630                 break;
631             }
632         }
633 
634         if (i == InternalNameLength)
635         {
636             PrefixLength = i;
637         }
638 
639         break;
640 
641     default:
642         break;
643     }
644 
645     /*
646      * Check for object names. Note that there could be 0-255 of these
647      * 4-byte elements.
648      */
649     if (PrefixLength < InternalNameLength)
650     {
651         switch (InternalName[PrefixLength])
652         {
653         case AML_MULTI_NAME_PREFIX_OP:
654 
655             /* <count> 4-byte names */
656 
657             NamesIndex = PrefixLength + 2;
658             NumSegments = (UINT8)
659                 InternalName[(ACPI_SIZE) PrefixLength + 1];
660             break;
661 
662         case AML_DUAL_NAME_PREFIX:
663 
664             /* Two 4-byte names */
665 
666             NamesIndex = PrefixLength + 1;
667             NumSegments = 2;
668             break;
669 
670         case 0:
671 
672             /* NullName */
673 
674             NamesIndex = 0;
675             NumSegments = 0;
676             break;
677 
678         default:
679 
680             /* one 4-byte name */
681 
682             NamesIndex = PrefixLength;
683             NumSegments = 1;
684             break;
685         }
686     }
687 
688     /*
689      * Calculate the length of ConvertedName, which equals the length
690      * of the prefix, length of all object names, length of any required
691      * punctuation ('.') between object names, plus the NULL terminator.
692      */
693     RequiredLength = PrefixLength + (4 * NumSegments) +
694                         ((NumSegments > 0) ? (NumSegments - 1) : 0) + 1;
695 
696     /*
697      * Check to see if we're still in bounds. If not, there's a problem
698      * with InternalName (invalid format).
699      */
700     if (RequiredLength > InternalNameLength)
701     {
702         ACPI_ERROR ((AE_INFO, "Invalid internal name"));
703         return_ACPI_STATUS (AE_BAD_PATHNAME);
704     }
705 
706     /* Build the ConvertedName */
707 
708     *ConvertedName = ACPI_ALLOCATE_ZEROED (RequiredLength);
709     if (!(*ConvertedName))
710     {
711         return_ACPI_STATUS (AE_NO_MEMORY);
712     }
713 
714     j = 0;
715 
716     for (i = 0; i < PrefixLength; i++)
717     {
718         (*ConvertedName)[j++] = InternalName[i];
719     }
720 
721     if (NumSegments > 0)
722     {
723         for (i = 0; i < NumSegments; i++)
724         {
725             if (i > 0)
726             {
727                 (*ConvertedName)[j++] = '.';
728             }
729 
730             /* Copy and validate the 4-char name segment */
731 
732             ACPI_MOVE_NAME (&(*ConvertedName)[j], &InternalName[NamesIndex]);
733             AcpiUtRepairName (&(*ConvertedName)[j]);
734 
735             j += ACPI_NAME_SIZE;
736             NamesIndex += ACPI_NAME_SIZE;
737         }
738     }
739 
740     if (ConvertedNameLength)
741     {
742         *ConvertedNameLength = (UINT32) RequiredLength;
743     }
744 
745     return_ACPI_STATUS (AE_OK);
746 }
747 
748 
749 /*******************************************************************************
750  *
751  * FUNCTION:    AcpiNsValidateHandle
752  *
753  * PARAMETERS:  Handle          - Handle to be validated and typecast to a
754  *                                namespace node.
755  *
756  * RETURN:      A pointer to a namespace node
757  *
758  * DESCRIPTION: Convert a namespace handle to a namespace node. Handles special
759  *              cases for the root node.
760  *
761  * NOTE: Real integer handles would allow for more verification
762  *       and keep all pointers within this subsystem - however this introduces
763  *       more overhead and has not been necessary to this point. Drivers
764  *       holding handles are typically notified before a node becomes invalid
765  *       due to a table unload.
766  *
767  ******************************************************************************/
768 
769 ACPI_NAMESPACE_NODE *
770 AcpiNsValidateHandle (
771     ACPI_HANDLE             Handle)
772 {
773 
774     ACPI_FUNCTION_ENTRY ();
775 
776 
777     /* Parameter validation */
778 
779     if ((!Handle) || (Handle == ACPI_ROOT_OBJECT))
780     {
781         return (AcpiGbl_RootNode);
782     }
783 
784     /* We can at least attempt to verify the handle */
785 
786     if (ACPI_GET_DESCRIPTOR_TYPE (Handle) != ACPI_DESC_TYPE_NAMED)
787     {
788         return (NULL);
789     }
790 
791     return (ACPI_CAST_PTR (ACPI_NAMESPACE_NODE, Handle));
792 }
793 
794 
795 /*******************************************************************************
796  *
797  * FUNCTION:    AcpiNsTerminate
798  *
799  * PARAMETERS:  none
800  *
801  * RETURN:      none
802  *
803  * DESCRIPTION: free memory allocated for namespace and ACPI table storage.
804  *
805  ******************************************************************************/
806 
807 void
808 AcpiNsTerminate (
809     void)
810 {
811     ACPI_OPERAND_OBJECT     *ObjDesc;
812 
813 
814     ACPI_FUNCTION_TRACE (NsTerminate);
815 
816 
817     /*
818      * 1) Free the entire namespace -- all nodes and objects
819      *
820      * Delete all object descriptors attached to namepsace nodes
821      */
822     AcpiNsDeleteNamespaceSubtree (AcpiGbl_RootNode);
823 
824     /* Detach any objects attached to the root */
825 
826     ObjDesc = AcpiNsGetAttachedObject (AcpiGbl_RootNode);
827     if (ObjDesc)
828     {
829         AcpiNsDetachObject (AcpiGbl_RootNode);
830     }
831 
832     ACPI_DEBUG_PRINT ((ACPI_DB_INFO, "Namespace freed\n"));
833     return_VOID;
834 }
835 
836 
837 /*******************************************************************************
838  *
839  * FUNCTION:    AcpiNsOpensScope
840  *
841  * PARAMETERS:  Type        - A valid namespace type
842  *
843  * RETURN:      NEWSCOPE if the passed type "opens a name scope" according
844  *              to the ACPI specification, else 0
845  *
846  ******************************************************************************/
847 
848 UINT32
849 AcpiNsOpensScope (
850     ACPI_OBJECT_TYPE        Type)
851 {
852     ACPI_FUNCTION_TRACE_STR (NsOpensScope, AcpiUtGetTypeName (Type));
853 
854 
855     if (!AcpiUtValidObjectType (Type))
856     {
857         /* type code out of range  */
858 
859         ACPI_WARNING ((AE_INFO, "Invalid Object Type 0x%X", Type));
860         return_UINT32 (ACPI_NS_NORMAL);
861     }
862 
863     return_UINT32 (((UINT32) AcpiGbl_NsProperties[Type]) & ACPI_NS_NEWSCOPE);
864 }
865 
866 
867 /*******************************************************************************
868  *
869  * FUNCTION:    AcpiNsGetNode
870  *
871  * PARAMETERS:  *Pathname   - Name to be found, in external (ASL) format. The
872  *                            \ (backslash) and ^ (carat) prefixes, and the
873  *                            . (period) to separate segments are supported.
874  *              PrefixNode   - Root of subtree to be searched, or NS_ALL for the
875  *                            root of the name space. If Name is fully
876  *                            qualified (first INT8 is '\'), the passed value
877  *                            of Scope will not be accessed.
878  *              Flags       - Used to indicate whether to perform upsearch or
879  *                            not.
880  *              ReturnNode  - Where the Node is returned
881  *
882  * DESCRIPTION: Look up a name relative to a given scope and return the
883  *              corresponding Node. NOTE: Scope can be null.
884  *
885  * MUTEX:       Locks namespace
886  *
887  ******************************************************************************/
888 
889 ACPI_STATUS
890 AcpiNsGetNode (
891     ACPI_NAMESPACE_NODE     *PrefixNode,
892     const char              *Pathname,
893     UINT32                  Flags,
894     ACPI_NAMESPACE_NODE     **ReturnNode)
895 {
896     ACPI_GENERIC_STATE      ScopeInfo;
897     ACPI_STATUS             Status;
898     char                    *InternalPath;
899 
900 
901     ACPI_FUNCTION_TRACE_PTR (NsGetNode, ACPI_CAST_PTR (char, Pathname));
902 
903 
904     if (!Pathname)
905     {
906         *ReturnNode = PrefixNode;
907         if (!PrefixNode)
908         {
909             *ReturnNode = AcpiGbl_RootNode;
910         }
911         return_ACPI_STATUS (AE_OK);
912     }
913 
914     /* Convert path to internal representation */
915 
916     Status = AcpiNsInternalizeName (Pathname, &InternalPath);
917     if (ACPI_FAILURE (Status))
918     {
919         return_ACPI_STATUS (Status);
920     }
921 
922     /* Must lock namespace during lookup */
923 
924     Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
925     if (ACPI_FAILURE (Status))
926     {
927         goto Cleanup;
928     }
929 
930     /* Setup lookup scope (search starting point) */
931 
932     ScopeInfo.Scope.Node = PrefixNode;
933 
934     /* Lookup the name in the namespace */
935 
936     Status = AcpiNsLookup (&ScopeInfo, InternalPath, ACPI_TYPE_ANY,
937                 ACPI_IMODE_EXECUTE, (Flags | ACPI_NS_DONT_OPEN_SCOPE),
938                 NULL, ReturnNode);
939     if (ACPI_FAILURE (Status))
940     {
941         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "%s, %s\n",
942                 Pathname, AcpiFormatException (Status)));
943     }
944 
945     (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
946 
947 Cleanup:
948     ACPI_FREE (InternalPath);
949     return_ACPI_STATUS (Status);
950 }
951