drivers/bus/acpi/acpica/namespace/nsnames.c

   1 /*******************************************************************************
   2  *
   3  * Module Name: nsnames - Name manipulation and search
   4  *
   5  ******************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2017, 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 "amlcode.h"
  47 #include "acnamesp.h"
  48
  49
  50 #define _COMPONENT          ACPI_NAMESPACE
  51         ACPI_MODULE_NAME    ("nsnames")
  52
  53 /* Local Prototypes */
  54
  55 static void
  56 AcpiNsNormalizePathname (
  57     char                    *OriginalPath);
  58
  59
  60 /*******************************************************************************
  61  *
  62  * FUNCTION:    AcpiNsGetExternalPathname
  63  *
  64  * PARAMETERS:  Node            - Namespace node whose pathname is needed
  65  *
  66  * RETURN:      Pointer to storage containing the fully qualified name of
  67  *              the node, In external format (name segments separated by path
  68  *              separators.)
  69  *
  70  * DESCRIPTION: Used to obtain the full pathname to a namespace node, usually
  71  *              for error and debug statements.
  72  *
  73  ******************************************************************************/
  74
  75 char *
  76 AcpiNsGetExternalPathname (
  77     ACPI_NAMESPACE_NODE     *Node)
  78 {
  79     char                    *NameBuffer;
  80
  81
  82     ACPI_FUNCTION_TRACE_PTR (NsGetExternalPathname, Node);
  83
  84
  85     NameBuffer = AcpiNsGetNormalizedPathname (Node, FALSE);
  86     return_PTR (NameBuffer);
  87 }
  88
  89
  90 /*******************************************************************************
  91  *
  92  * FUNCTION:    AcpiNsGetPathnameLength
  93  *
  94  * PARAMETERS:  Node        - Namespace node
  95  *
  96  * RETURN:      Length of path, including prefix
  97  *
  98  * DESCRIPTION: Get the length of the pathname string for this node
  99  *
 100  ******************************************************************************/
 101
 102 ACPI_SIZE
 103 AcpiNsGetPathnameLength (
 104     ACPI_NAMESPACE_NODE     *Node)
 105 {
 106     ACPI_SIZE               Size;
 107
 108
 109     /* Validate the Node */
 110
 111     if (ACPI_GET_DESCRIPTOR_TYPE (Node) != ACPI_DESC_TYPE_NAMED)
 112     {
 113         ACPI_ERROR ((AE_INFO,
 114             "Invalid/cached reference target node: %p, descriptor type %d",
 115             Node, ACPI_GET_DESCRIPTOR_TYPE (Node)));
 116         return (0);
 117     }
 118
 119     Size = AcpiNsBuildNormalizedPath (Node, NULL, 0, FALSE);
 120     return (Size);
 121 }
 122
 123
 124 /*******************************************************************************
 125  *
 126  * FUNCTION:    AcpiNsHandleToName
 127  *
 128  * PARAMETERS:  TargetHandle            - Handle of named object whose name is
 129  *                                        to be found
 130  *              Buffer                  - Where the name is returned
 131  *
 132  * RETURN:      Status, Buffer is filled with name if status is AE_OK
 133  *
 134  * DESCRIPTION: Build and return a full namespace name
 135  *
 136  ******************************************************************************/
 137
 138 ACPI_STATUS
 139 AcpiNsHandleToName (
 140     ACPI_HANDLE             TargetHandle,
 141     ACPI_BUFFER             *Buffer)
 142 {
 143     ACPI_STATUS             Status;
 144     ACPI_NAMESPACE_NODE     *Node;
 145     const char              *NodeName;
 146
 147
 148     ACPI_FUNCTION_TRACE_PTR (NsHandleToName, TargetHandle);
 149
 150
 151     Node = AcpiNsValidateHandle (TargetHandle);
 152     if (!Node)
 153     {
 154         return_ACPI_STATUS (AE_BAD_PARAMETER);
 155     }
 156
 157     /* Validate/Allocate/Clear caller buffer */
 158
 159     Status = AcpiUtInitializeBuffer (Buffer, ACPI_PATH_SEGMENT_LENGTH);
 160     if (ACPI_FAILURE (Status))
 161     {
 162         return_ACPI_STATUS (Status);
 163     }
 164
 165     /* Just copy the ACPI name from the Node and zero terminate it */
 166
 167     NodeName = AcpiUtGetNodeName (Node);
 168     ACPI_MOVE_NAME (Buffer->Pointer, NodeName);
 169     ((char *) Buffer->Pointer) [ACPI_NAME_SIZE] = 0;
 170
 171     ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "%4.4s\n", (char *) Buffer->Pointer));
 172     return_ACPI_STATUS (AE_OK);
 173 }
 174
 175
 176 /*******************************************************************************
 177  *
 178  * FUNCTION:    AcpiNsHandleToPathname
 179  *
 180  * PARAMETERS:  TargetHandle            - Handle of named object whose name is
 181  *                                        to be found
 182  *              Buffer                  - Where the pathname is returned
 183  *              NoTrailing              - Remove trailing '_' for each name
 184  *                                        segment
 185  *
 186  * RETURN:      Status, Buffer is filled with pathname if status is AE_OK
 187  *
 188  * DESCRIPTION: Build and return a full namespace pathname
 189  *
 190  ******************************************************************************/
 191
 192 ACPI_STATUS
 193 AcpiNsHandleToPathname (
 194     ACPI_HANDLE             TargetHandle,
 195     ACPI_BUFFER             *Buffer,
 196     BOOLEAN                 NoTrailing)
 197 {
 198     ACPI_STATUS             Status;
 199     ACPI_NAMESPACE_NODE     *Node;
 200     ACPI_SIZE               RequiredSize;
 201
 202
 203     ACPI_FUNCTION_TRACE_PTR (NsHandleToPathname, TargetHandle);
 204
 205
 206     Node = AcpiNsValidateHandle (TargetHandle);
 207     if (!Node)
 208     {
 209         return_ACPI_STATUS (AE_BAD_PARAMETER);
 210     }
 211
 212     /* Determine size required for the caller buffer */
 213
 214     RequiredSize = AcpiNsBuildNormalizedPath (Node, NULL, 0, NoTrailing);
 215     if (!RequiredSize)
 216     {
 217         return_ACPI_STATUS (AE_BAD_PARAMETER);
 218     }
 219
 220     /* Validate/Allocate/Clear caller buffer */
 221
 222     Status = AcpiUtInitializeBuffer (Buffer, RequiredSize);
 223     if (ACPI_FAILURE (Status))
 224     {
 225         return_ACPI_STATUS (Status);
 226     }
 227
 228     /* Build the path in the caller buffer */
 229
 230     (void) AcpiNsBuildNormalizedPath (Node, Buffer->Pointer,
 231         RequiredSize, NoTrailing);
 232
 233     ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "%s [%X]\n",
 234         (char *) Buffer->Pointer, (UINT32) RequiredSize));
 235     return_ACPI_STATUS (AE_OK);
 236 }
 237
 238
 239 /*******************************************************************************
 240  *
 241  * FUNCTION:    AcpiNsBuildNormalizedPath
 242  *
 243  * PARAMETERS:  Node        - Namespace node
 244  *              FullPath    - Where the path name is returned
 245  *              PathSize    - Size of returned path name buffer
 246  *              NoTrailing  - Remove trailing '_' from each name segment
 247  *
 248  * RETURN:      Return 1 if the AML path is empty, otherwise returning (length
 249  *              of pathname + 1) which means the 'FullPath' contains a trailing
 250  *              null.
 251  *
 252  * DESCRIPTION: Build and return a full namespace pathname.
 253  *              Note that if the size of 'FullPath' isn't large enough to
 254  *              contain the namespace node's path name, the actual required
 255  *              buffer length is returned, and it should be greater than
 256  *              'PathSize'. So callers are able to check the returning value
 257  *              to determine the buffer size of 'FullPath'.
 258  *
 259  ******************************************************************************/
 260
 261 UINT32
 262 AcpiNsBuildNormalizedPath (
 263     ACPI_NAMESPACE_NODE     *Node,
 264     char                    *FullPath,
 265     UINT32                  PathSize,
 266     BOOLEAN                 NoTrailing)
 267 {
 268     UINT32                  Length = 0, i;
 269     char                    Name[ACPI_NAME_SIZE];
 270     BOOLEAN                 DoNoTrailing;
 271     char                    c, *Left, *Right;
 272     ACPI_NAMESPACE_NODE     *NextNode;
 273
 274
 275     ACPI_FUNCTION_TRACE_PTR (NsBuildNormalizedPath, Node);
 276
 277
 278 #define ACPI_PATH_PUT8(Path, Size, Byte, Length)    \
 279     do {                                            \
 280         if ((Length) < (Size))                      \
 281         {                                           \
 282             (Path)[(Length)] = (Byte);              \
 283         }                                           \
 284         (Length)++;                                 \
 285     } while (0)
 286
 287     /*
 288      * Make sure the PathSize is correct, so that we don't need to
 289      * validate both FullPath and PathSize.
 290      */
 291     if (!FullPath)
 292     {
 293         PathSize = 0;
 294     }
 295
 296     if (!Node)
 297     {
 298         goto BuildTrailingNull;
 299     }
 300
 301     NextNode = Node;
 302     while (NextNode && NextNode != AcpiGbl_RootNode)
 303     {
 304         if (NextNode != Node)
 305         {
 306             ACPI_PATH_PUT8(FullPath, PathSize, AML_DUAL_NAME_PREFIX, Length);
 307         }
 308
 309         ACPI_MOVE_32_TO_32 (Name, &NextNode->Name);
 310         DoNoTrailing = NoTrailing;
 311         for (i = 0; i < 4; i++)
 312         {
 313             c = Name[4-i-1];
 314             if (DoNoTrailing && c != '_')
 315             {
 316                 DoNoTrailing = FALSE;
 317             }
 318             if (!DoNoTrailing)
 319             {
 320                 ACPI_PATH_PUT8(FullPath, PathSize, c, Length);
 321             }
 322         }
 323
 324         NextNode = NextNode->Parent;
 325     }
 326
 327     ACPI_PATH_PUT8(FullPath, PathSize, AML_ROOT_PREFIX, Length);
 328
 329     /* Reverse the path string */
 330
 331     if (Length <= PathSize)
 332     {
 333         Left = FullPath;
 334         Right = FullPath+Length - 1;
 335
 336         while (Left < Right)
 337         {
 338             c = *Left;
 339             *Left++ = *Right;
 340             *Right-- = c;
 341         }
 342     }
 343
 344     /* Append the trailing null */
 345
 346 BuildTrailingNull:
 347     ACPI_PATH_PUT8 (FullPath, PathSize, '\0', Length);
 348
 349 #undef ACPI_PATH_PUT8
 350
 351     return_UINT32 (Length);
 352 }
 353
 354
 355 /*******************************************************************************
 356  *
 357  * FUNCTION:    AcpiNsGetNormalizedPathname
 358  *
 359  * PARAMETERS:  Node            - Namespace node whose pathname is needed
 360  *              NoTrailing      - Remove trailing '_' from each name segment
 361  *
 362  * RETURN:      Pointer to storage containing the fully qualified name of
 363  *              the node, In external format (name segments separated by path
 364  *              separators.)
 365  *
 366  * DESCRIPTION: Used to obtain the full pathname to a namespace node, usually
 367  *              for error and debug statements. All trailing '_' will be
 368  *              removed from the full pathname if 'NoTrailing' is specified..
 369  *
 370  ******************************************************************************/
 371
 372 char *
 373 AcpiNsGetNormalizedPathname (
 374     ACPI_NAMESPACE_NODE     *Node,
 375     BOOLEAN                 NoTrailing)
 376 {
 377     char                    *NameBuffer;
 378     ACPI_SIZE               Size;
 379
 380
 381     ACPI_FUNCTION_TRACE_PTR (NsGetNormalizedPathname, Node);
 382
 383
 384     /* Calculate required buffer size based on depth below root */
 385
 386     Size = AcpiNsBuildNormalizedPath (Node, NULL, 0, NoTrailing);
 387     if (!Size)
 388     {
 389         return_PTR (NULL);
 390     }
 391
 392     /* Allocate a buffer to be returned to caller */
 393
 394     NameBuffer = ACPI_ALLOCATE_ZEROED (Size);
 395     if (!NameBuffer)
 396     {
 397         ACPI_ERROR ((AE_INFO,
 398             "Could not allocate %u bytes", (UINT32) Size));
 399         return_PTR (NULL);
 400     }
 401
 402     /* Build the path in the allocated buffer */
 403
 404     (void) AcpiNsBuildNormalizedPath (Node, NameBuffer, Size, NoTrailing);
 405
 406     return_PTR (NameBuffer);
 407 }
 408
 409
 410 /*******************************************************************************
 411  *
 412  * FUNCTION:    AcpiNsBuildPrefixedPathname
 413  *
 414  * PARAMETERS:  PrefixScope         - Scope/Path that prefixes the internal path
 415  *              InternalPath        - Name or path of the namespace node
 416  *
 417  * RETURN:      None
 418  *
 419  * DESCRIPTION: Construct a fully qualified pathname from a concatenation of:
 420  *              1) Path associated with the PrefixScope namespace node
 421  *              2) External path representation of the Internal path
 422  *
 423  ******************************************************************************/
 424
 425 char *
 426 AcpiNsBuildPrefixedPathname (
 427     ACPI_GENERIC_STATE      *PrefixScope,
 428     const char              *InternalPath)
 429 {
 430     ACPI_STATUS             Status;
 431     char                    *FullPath = NULL;
 432     char                    *ExternalPath = NULL;
 433     char                    *PrefixPath = NULL;
 434     UINT32                  PrefixPathLength = 0;
 435
 436
 437     /* If there is a prefix, get the pathname to it */
 438
 439     if (PrefixScope && PrefixScope->Scope.Node)
 440     {
 441         PrefixPath = AcpiNsGetNormalizedPathname (PrefixScope->Scope.Node, TRUE);
 442         if (PrefixPath)
 443         {
 444             PrefixPathLength = strlen (PrefixPath);
 445         }
 446     }
 447
 448     Status = AcpiNsExternalizeName (ACPI_UINT32_MAX, InternalPath,
 449         NULL, &ExternalPath);
 450     if (ACPI_FAILURE (Status))
 451     {
 452         goto Cleanup;
 453     }
 454
 455     /* Merge the prefix path and the path. 2 is for one dot and trailing null */
 456
 457     FullPath = ACPI_ALLOCATE_ZEROED (
 458         PrefixPathLength + strlen (ExternalPath) + 2);
 459     if (!FullPath)
 460     {
 461         goto Cleanup;
 462     }
 463
 464     /* Don't merge if the External path is already fully qualified */
 465
 466     if (PrefixPath &&
 467         (*ExternalPath != '\\') &&
 468         (*ExternalPath != '^'))
 469     {
 470         strcat (FullPath, PrefixPath);
 471         if (PrefixPath[1])
 472         {
 473             strcat (FullPath, ".");
 474         }
 475     }
 476
 477     AcpiNsNormalizePathname (ExternalPath);
 478     strcat (FullPath, ExternalPath);
 479
 480 Cleanup:
 481     if (PrefixPath)
 482     {
 483         ACPI_FREE (PrefixPath);
 484     }
 485     if (ExternalPath)
 486     {
 487         ACPI_FREE (ExternalPath);
 488     }
 489
 490     return (FullPath);
 491 }
 492
 493
 494 /*******************************************************************************
 495  *
 496  * FUNCTION:    AcpiNsNormalizePathname
 497  *
 498  * PARAMETERS:  OriginalPath        - Path to be normalized, in External format
 499  *
 500  * RETURN:      The original path is processed in-place
 501  *
 502  * DESCRIPTION: Remove trailing underscores from each element of a path.
 503  *
 504  *              For example:  \A___.B___.C___ becomes \A.B.C
 505  *
 506  ******************************************************************************/
 507
 508 static void
 509 AcpiNsNormalizePathname (
 510     char                    *OriginalPath)
 511 {
 512     char                    *InputPath = OriginalPath;
 513     char                    *NewPathBuffer;
 514     char                    *NewPath;
 515     UINT32                  i;
 516
 517
 518     /* Allocate a temp buffer in which to construct the new path */
 519
 520     NewPathBuffer = ACPI_ALLOCATE_ZEROED (strlen (InputPath) + 1);
 521     NewPath = NewPathBuffer;
 522     if (!NewPathBuffer)
 523     {
 524         return;
 525     }
 526
 527     /* Special characters may appear at the beginning of the path */
 528
 529     if (*InputPath == '\\')
 530     {
 531         *NewPath = *InputPath;
 532         NewPath++;
 533         InputPath++;
 534     }
 535
 536     while (*InputPath == '^')
 537     {
 538         *NewPath = *InputPath;
 539         NewPath++;
 540         InputPath++;
 541     }
 542
 543     /* Remainder of the path */
 544
 545     while (*InputPath)
 546     {
 547         /* Do one nameseg at a time */
 548
 549         for (i = 0; (i < ACPI_NAME_SIZE) && *InputPath; i++)
 550         {
 551             if ((i == 0) || (*InputPath != '_')) /* First char is allowed to be underscore */
 552             {
 553                 *NewPath = *InputPath;
 554                 NewPath++;
 555             }
 556
 557             InputPath++;
 558         }
 559
 560         /* Dot means that there are more namesegs to come */
 561
 562         if (*InputPath == '.')
 563         {
 564             *NewPath = *InputPath;
 565             NewPath++;
 566             InputPath++;
 567         }
 568     }
 569
 570     *NewPath = 0;
 571     strcpy (OriginalPath, NewPathBuffer);
 572     ACPI_FREE (NewPathBuffer);
 573 }