Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame^] | 1 | /******************************************************************************* |
| 2 | * |
| 3 | * Module Name: nsnames - Name manipulation and search |
| 4 | * |
| 5 | ******************************************************************************/ |
| 6 | |
| 7 | /* |
| 8 | * Copyright (C) 2000 - 2005, R. Byron Moore |
| 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 | |
| 45 | #include <acpi/acpi.h> |
| 46 | #include <acpi/amlcode.h> |
| 47 | #include <acpi/acnamesp.h> |
| 48 | |
| 49 | |
| 50 | #define _COMPONENT ACPI_NAMESPACE |
| 51 | ACPI_MODULE_NAME ("nsnames") |
| 52 | |
| 53 | |
| 54 | /******************************************************************************* |
| 55 | * |
| 56 | * FUNCTION: acpi_ns_build_external_path |
| 57 | * |
| 58 | * PARAMETERS: Node - NS node whose pathname is needed |
| 59 | * Size - Size of the pathname |
| 60 | * *name_buffer - Where to return the pathname |
| 61 | * |
| 62 | * RETURN: Places the pathname into the name_buffer, in external format |
| 63 | * (name segments separated by path separators) |
| 64 | * |
| 65 | * DESCRIPTION: Generate a full pathaname |
| 66 | * |
| 67 | ******************************************************************************/ |
| 68 | |
| 69 | void |
| 70 | acpi_ns_build_external_path ( |
| 71 | struct acpi_namespace_node *node, |
| 72 | acpi_size size, |
| 73 | char *name_buffer) |
| 74 | { |
| 75 | acpi_size index; |
| 76 | struct acpi_namespace_node *parent_node; |
| 77 | |
| 78 | |
| 79 | ACPI_FUNCTION_NAME ("ns_build_external_path"); |
| 80 | |
| 81 | |
| 82 | /* Special case for root */ |
| 83 | |
| 84 | index = size - 1; |
| 85 | if (index < ACPI_NAME_SIZE) { |
| 86 | name_buffer[0] = AML_ROOT_PREFIX; |
| 87 | name_buffer[1] = 0; |
| 88 | return; |
| 89 | } |
| 90 | |
| 91 | /* Store terminator byte, then build name backwards */ |
| 92 | |
| 93 | parent_node = node; |
| 94 | name_buffer[index] = 0; |
| 95 | |
| 96 | while ((index > ACPI_NAME_SIZE) && (parent_node != acpi_gbl_root_node)) { |
| 97 | index -= ACPI_NAME_SIZE; |
| 98 | |
| 99 | /* Put the name into the buffer */ |
| 100 | |
| 101 | ACPI_MOVE_32_TO_32 ((name_buffer + index), &parent_node->name); |
| 102 | parent_node = acpi_ns_get_parent_node (parent_node); |
| 103 | |
| 104 | /* Prefix name with the path separator */ |
| 105 | |
| 106 | index--; |
| 107 | name_buffer[index] = ACPI_PATH_SEPARATOR; |
| 108 | } |
| 109 | |
| 110 | /* Overwrite final separator with the root prefix character */ |
| 111 | |
| 112 | name_buffer[index] = AML_ROOT_PREFIX; |
| 113 | |
| 114 | if (index != 0) { |
| 115 | ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, |
| 116 | "Could not construct pathname; index=%X, size=%X, Path=%s\n", |
| 117 | (u32) index, (u32) size, &name_buffer[size])); |
| 118 | } |
| 119 | |
| 120 | return; |
| 121 | } |
| 122 | |
| 123 | |
| 124 | #ifdef ACPI_DEBUG_OUTPUT |
| 125 | /******************************************************************************* |
| 126 | * |
| 127 | * FUNCTION: acpi_ns_get_external_pathname |
| 128 | * |
| 129 | * PARAMETERS: Node - NS node whose pathname is needed |
| 130 | * |
| 131 | * RETURN: Pointer to storage containing the fully qualified name of |
| 132 | * the node, In external format (name segments separated by path |
| 133 | * separators.) |
| 134 | * |
| 135 | * DESCRIPTION: Used for debug printing in acpi_ns_search_table(). |
| 136 | * |
| 137 | ******************************************************************************/ |
| 138 | |
| 139 | char * |
| 140 | acpi_ns_get_external_pathname ( |
| 141 | struct acpi_namespace_node *node) |
| 142 | { |
| 143 | char *name_buffer; |
| 144 | acpi_size size; |
| 145 | |
| 146 | |
| 147 | ACPI_FUNCTION_TRACE_PTR ("ns_get_external_pathname", node); |
| 148 | |
| 149 | |
| 150 | /* Calculate required buffer size based on depth below root */ |
| 151 | |
| 152 | size = acpi_ns_get_pathname_length (node); |
| 153 | |
| 154 | /* Allocate a buffer to be returned to caller */ |
| 155 | |
| 156 | name_buffer = ACPI_MEM_CALLOCATE (size); |
| 157 | if (!name_buffer) { |
| 158 | ACPI_REPORT_ERROR (("ns_get_table_pathname: allocation failure\n")); |
| 159 | return_PTR (NULL); |
| 160 | } |
| 161 | |
| 162 | /* Build the path in the allocated buffer */ |
| 163 | |
| 164 | acpi_ns_build_external_path (node, size, name_buffer); |
| 165 | return_PTR (name_buffer); |
| 166 | } |
| 167 | #endif |
| 168 | |
| 169 | |
| 170 | /******************************************************************************* |
| 171 | * |
| 172 | * FUNCTION: acpi_ns_get_pathname_length |
| 173 | * |
| 174 | * PARAMETERS: Node - Namespace node |
| 175 | * |
| 176 | * RETURN: Length of path, including prefix |
| 177 | * |
| 178 | * DESCRIPTION: Get the length of the pathname string for this node |
| 179 | * |
| 180 | ******************************************************************************/ |
| 181 | |
| 182 | acpi_size |
| 183 | acpi_ns_get_pathname_length ( |
| 184 | struct acpi_namespace_node *node) |
| 185 | { |
| 186 | acpi_size size; |
| 187 | struct acpi_namespace_node *next_node; |
| 188 | |
| 189 | |
| 190 | ACPI_FUNCTION_ENTRY (); |
| 191 | |
| 192 | |
| 193 | /* |
| 194 | * Compute length of pathname as 5 * number of name segments. |
| 195 | * Go back up the parent tree to the root |
| 196 | */ |
| 197 | size = 0; |
| 198 | next_node = node; |
| 199 | |
| 200 | while (next_node && (next_node != acpi_gbl_root_node)) { |
| 201 | size += ACPI_PATH_SEGMENT_LENGTH; |
| 202 | next_node = acpi_ns_get_parent_node (next_node); |
| 203 | } |
| 204 | |
| 205 | if (!size) { |
| 206 | size = 1; /* Root node case */ |
| 207 | } |
| 208 | |
| 209 | return (size + 1); /* +1 for null string terminator */ |
| 210 | } |
| 211 | |
| 212 | |
| 213 | /******************************************************************************* |
| 214 | * |
| 215 | * FUNCTION: acpi_ns_handle_to_pathname |
| 216 | * |
| 217 | * PARAMETERS: target_handle - Handle of named object whose name is |
| 218 | * to be found |
| 219 | * Buffer - Where the pathname is returned |
| 220 | * |
| 221 | * RETURN: Status, Buffer is filled with pathname if status is AE_OK |
| 222 | * |
| 223 | * DESCRIPTION: Build and return a full namespace pathname |
| 224 | * |
| 225 | ******************************************************************************/ |
| 226 | |
| 227 | acpi_status |
| 228 | acpi_ns_handle_to_pathname ( |
| 229 | acpi_handle target_handle, |
| 230 | struct acpi_buffer *buffer) |
| 231 | { |
| 232 | acpi_status status; |
| 233 | struct acpi_namespace_node *node; |
| 234 | acpi_size required_size; |
| 235 | |
| 236 | |
| 237 | ACPI_FUNCTION_TRACE_PTR ("ns_handle_to_pathname", target_handle); |
| 238 | |
| 239 | |
| 240 | node = acpi_ns_map_handle_to_node (target_handle); |
| 241 | if (!node) { |
| 242 | return_ACPI_STATUS (AE_BAD_PARAMETER); |
| 243 | } |
| 244 | |
| 245 | /* Determine size required for the caller buffer */ |
| 246 | |
| 247 | required_size = acpi_ns_get_pathname_length (node); |
| 248 | |
| 249 | /* Validate/Allocate/Clear caller buffer */ |
| 250 | |
| 251 | status = acpi_ut_initialize_buffer (buffer, required_size); |
| 252 | if (ACPI_FAILURE (status)) { |
| 253 | return_ACPI_STATUS (status); |
| 254 | } |
| 255 | |
| 256 | /* Build the path in the caller buffer */ |
| 257 | |
| 258 | acpi_ns_build_external_path (node, required_size, buffer->pointer); |
| 259 | |
| 260 | ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "%s [%X] \n", |
| 261 | (char *) buffer->pointer, (u32) required_size)); |
| 262 | return_ACPI_STATUS (AE_OK); |
| 263 | } |
| 264 | |
| 265 | |