reactos/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 - 2016, 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
  54 /*******************************************************************************
  55  *
  56  * FUNCTION:    AcpiNsGetExternalPathname
  57  *
  58  * PARAMETERS:  Node            - Namespace node whose pathname is needed
  59  *
  60  * RETURN:      Pointer to storage containing the fully qualified name of
  61  *              the node, In external format (name segments separated by path
  62  *              separators.)
  63  *
  64  * DESCRIPTION: Used to obtain the full pathname to a namespace node, usually
  65  *              for error and debug statements.
  66  *
  67  ******************************************************************************/
  68
  69 char *
  70 AcpiNsGetExternalPathname (
  71     ACPI_NAMESPACE_NODE     *Node)
  72 {
  73     char                    *NameBuffer;
  74
  75
  76     ACPI_FUNCTION_TRACE_PTR (NsGetExternalPathname, Node);
  77
  78
  79     NameBuffer = AcpiNsGetNormalizedPathname (Node, FALSE);
  80     return_PTR (NameBuffer);
  81 }
  82
  83
  84 /*******************************************************************************
  85  *
  86  * FUNCTION:    AcpiNsGetPathnameLength
  87  *
  88  * PARAMETERS:  Node        - Namespace node
  89  *
  90  * RETURN:      Length of path, including prefix
  91  *
  92  * DESCRIPTION: Get the length of the pathname string for this node
  93  *
  94  ******************************************************************************/
  95
  96 ACPI_SIZE
  97 AcpiNsGetPathnameLength (
  98     ACPI_NAMESPACE_NODE     *Node)
  99 {
 100     ACPI_SIZE               Size;
 101
 102
 103     ACPI_FUNCTION_ENTRY ();
 104
 105
 106     Size = AcpiNsBuildNormalizedPath (Node, NULL, 0, FALSE);
 107     return (Size);
 108 }
 109
 110
 111 /*******************************************************************************
 112  *
 113  * FUNCTION:    AcpiNsHandleToPathname
 114  *
 115  * PARAMETERS:  TargetHandle            - Handle of named object whose name is
 116  *                                        to be found
 117  *              Buffer                  - Where the pathname is returned
 118  *              NoTrailing              - Remove trailing '_' for each name
 119  *                                        segment
 120  *
 121  * RETURN:      Status, Buffer is filled with pathname if status is AE_OK
 122  *
 123  * DESCRIPTION: Build and return a full namespace pathname
 124  *
 125  ******************************************************************************/
 126
 127 ACPI_STATUS
 128 AcpiNsHandleToPathname (
 129     ACPI_HANDLE             TargetHandle,
 130     ACPI_BUFFER             *Buffer,
 131     BOOLEAN                 NoTrailing)
 132 {
 133     ACPI_STATUS             Status;
 134     ACPI_NAMESPACE_NODE     *Node;
 135     ACPI_SIZE               RequiredSize;
 136
 137
 138     ACPI_FUNCTION_TRACE_PTR (NsHandleToPathname, TargetHandle);
 139
 140
 141     Node = AcpiNsValidateHandle (TargetHandle);
 142     if (!Node)
 143     {
 144         return_ACPI_STATUS (AE_BAD_PARAMETER);
 145     }
 146
 147     /* Determine size required for the caller buffer */
 148
 149     RequiredSize = AcpiNsBuildNormalizedPath (Node, NULL, 0, NoTrailing);
 150     if (!RequiredSize)
 151     {
 152         return_ACPI_STATUS (AE_BAD_PARAMETER);
 153     }
 154
 155     /* Validate/Allocate/Clear caller buffer */
 156
 157     Status = AcpiUtInitializeBuffer (Buffer, RequiredSize);
 158     if (ACPI_FAILURE (Status))
 159     {
 160         return_ACPI_STATUS (Status);
 161     }
 162
 163     /* Build the path in the caller buffer */
 164
 165     (void) AcpiNsBuildNormalizedPath (Node, Buffer->Pointer,
 166         RequiredSize, NoTrailing);
 167     if (ACPI_FAILURE (Status))
 168     {
 169         return_ACPI_STATUS (Status);
 170     }
 171
 172     ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "%s [%X]\n",
 173         (char *) Buffer->Pointer, (UINT32) RequiredSize));
 174     return_ACPI_STATUS (AE_OK);
 175 }
 176
 177
 178 /*******************************************************************************
 179  *
 180  * FUNCTION:    AcpiNsBuildNormalizedPath
 181  *
 182  * PARAMETERS:  Node        - Namespace node
 183  *              FullPath    - Where the path name is returned
 184  *              PathSize    - Size of returned path name buffer
 185  *              NoTrailing  - Remove trailing '_' from each name segment
 186  *
 187  * RETURN:      Return 1 if the AML path is empty, otherwise returning (length
 188  *              of pathname + 1) which means the 'FullPath' contains a trailing
 189  *              null.
 190  *
 191  * DESCRIPTION: Build and return a full namespace pathname.
 192  *              Note that if the size of 'FullPath' isn't large enough to
 193  *              contain the namespace node's path name, the actual required
 194  *              buffer length is returned, and it should be greater than
 195  *              'PathSize'. So callers are able to check the returning value
 196  *              to determine the buffer size of 'FullPath'.
 197  *
 198  ******************************************************************************/
 199
 200 UINT32
 201 AcpiNsBuildNormalizedPath (
 202     ACPI_NAMESPACE_NODE     *Node,
 203     char                    *FullPath,
 204     UINT32                  PathSize,
 205     BOOLEAN                 NoTrailing)
 206 {
 207     UINT32                  Length = 0, i;
 208     char                    Name[ACPI_NAME_SIZE];
 209     BOOLEAN                 DoNoTrailing;
 210     char                    c, *Left, *Right;
 211     ACPI_NAMESPACE_NODE     *NextNode;
 212
 213
 214     ACPI_FUNCTION_TRACE_PTR (NsBuildNormalizedPath, Node);
 215
 216
 217 #define ACPI_PATH_PUT8(Path, Size, Byte, Length)    \
 218     do {                                            \
 219         if ((Length) < (Size))                      \
 220         {                                           \
 221             (Path)[(Length)] = (Byte);              \
 222         }                                           \
 223         (Length)++;                                 \
 224     } while (0)
 225
 226     /*
 227      * Make sure the PathSize is correct, so that we don't need to
 228      * validate both FullPath and PathSize.
 229      */
 230     if (!FullPath)
 231     {
 232         PathSize = 0;
 233     }
 234
 235     if (!Node)
 236     {
 237         goto BuildTrailingNull;
 238     }
 239
 240     NextNode = Node;
 241     while (NextNode && NextNode != AcpiGbl_RootNode)
 242     {
 243         if (NextNode != Node)
 244         {
 245             ACPI_PATH_PUT8(FullPath, PathSize, AML_DUAL_NAME_PREFIX, Length);
 246         }
 247
 248         ACPI_MOVE_32_TO_32 (Name, &NextNode->Name);
 249         DoNoTrailing = NoTrailing;
 250         for (i = 0; i < 4; i++)
 251         {
 252             c = Name[4-i-1];
 253             if (DoNoTrailing && c != '_')
 254             {
 255                 DoNoTrailing = FALSE;
 256             }
 257             if (!DoNoTrailing)
 258             {
 259                 ACPI_PATH_PUT8(FullPath, PathSize, c, Length);
 260             }
 261         }
 262
 263         NextNode = NextNode->Parent;
 264     }
 265
 266     ACPI_PATH_PUT8(FullPath, PathSize, AML_ROOT_PREFIX, Length);
 267
 268     /* Reverse the path string */
 269
 270     if (Length <= PathSize)
 271     {
 272         Left = FullPath;
 273         Right = FullPath+Length - 1;
 274
 275         while (Left < Right)
 276         {
 277             c = *Left;
 278             *Left++ = *Right;
 279             *Right-- = c;
 280         }
 281     }
 282
 283     /* Append the trailing null */
 284
 285 BuildTrailingNull:
 286     ACPI_PATH_PUT8 (FullPath, PathSize, '\0', Length);
 287
 288 #undef ACPI_PATH_PUT8
 289
 290     return_UINT32 (Length);
 291 }
 292
 293
 294 /*******************************************************************************
 295  *
 296  * FUNCTION:    AcpiNsGetNormalizedPathname
 297  *
 298  * PARAMETERS:  Node            - Namespace node whose pathname is needed
 299  *              NoTrailing      - Remove trailing '_' from each name segment
 300  *
 301  * RETURN:      Pointer to storage containing the fully qualified name of
 302  *              the node, In external format (name segments separated by path
 303  *              separators.)
 304  *
 305  * DESCRIPTION: Used to obtain the full pathname to a namespace node, usually
 306  *              for error and debug statements. All trailing '_' will be
 307  *              removed from the full pathname if 'NoTrailing' is specified..
 308  *
 309  ******************************************************************************/
 310
 311 char *
 312 AcpiNsGetNormalizedPathname (
 313     ACPI_NAMESPACE_NODE     *Node,
 314     BOOLEAN                 NoTrailing)
 315 {
 316     char                    *NameBuffer;
 317     ACPI_SIZE               Size;
 318
 319
 320     ACPI_FUNCTION_TRACE_PTR (NsGetNormalizedPathname, Node);
 321
 322
 323     /* Calculate required buffer size based on depth below root */
 324
 325     Size = AcpiNsBuildNormalizedPath (Node, NULL, 0, NoTrailing);
 326     if (!Size)
 327     {
 328         return_PTR (NULL);
 329     }
 330
 331     /* Allocate a buffer to be returned to caller */
 332
 333     NameBuffer = ACPI_ALLOCATE_ZEROED (Size);
 334     if (!NameBuffer)
 335     {
 336         ACPI_ERROR ((AE_INFO,
 337             "Could not allocate %u bytes", (UINT32) Size));
 338         return_PTR (NULL);
 339     }
 340
 341     /* Build the path in the allocated buffer */
 342
 343     (void) AcpiNsBuildNormalizedPath (Node, NameBuffer, Size, NoTrailing);
 344
 345     return_PTR (NameBuffer);
 346 }