1 /******************************************************************************* 2 * 3 * Module Name: nsnames - Name manipulation and search 4 * 5 ******************************************************************************/ 6 7 /* 8 * Copyright (C) 2000 - 2015, 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/acpi.h> 45 #include "accommon.h" 46 #include "amlcode.h" 47 #include "acnamesp.h" 48 49 #define _COMPONENT ACPI_NAMESPACE 50 ACPI_MODULE_NAME("nsnames") 51 52 /******************************************************************************* 53 * 54 * FUNCTION: acpi_ns_get_external_pathname 55 * 56 * PARAMETERS: node - Namespace node whose pathname is needed 57 * 58 * RETURN: Pointer to storage containing the fully qualified name of 59 * the node, In external format (name segments separated by path 60 * separators.) 61 * 62 * DESCRIPTION: Used to obtain the full pathname to a namespace node, usually 63 * for error and debug statements. 64 * 65 ******************************************************************************/ 66 char *acpi_ns_get_external_pathname(struct acpi_namespace_node *node) 67 { 68 char *name_buffer; 69 70 ACPI_FUNCTION_TRACE_PTR(ns_get_external_pathname, node); 71 72 name_buffer = acpi_ns_get_normalized_pathname(node, FALSE); 73 74 return_PTR(name_buffer); 75 } 76 77 /******************************************************************************* 78 * 79 * FUNCTION: acpi_ns_get_pathname_length 80 * 81 * PARAMETERS: node - Namespace node 82 * 83 * RETURN: Length of path, including prefix 84 * 85 * DESCRIPTION: Get the length of the pathname string for this node 86 * 87 ******************************************************************************/ 88 89 acpi_size acpi_ns_get_pathname_length(struct acpi_namespace_node *node) 90 { 91 acpi_size size; 92 93 ACPI_FUNCTION_ENTRY(); 94 95 size = acpi_ns_build_normalized_path(node, NULL, 0, FALSE); 96 97 return (size); 98 } 99 100 /******************************************************************************* 101 * 102 * FUNCTION: acpi_ns_handle_to_pathname 103 * 104 * PARAMETERS: target_handle - Handle of named object whose name is 105 * to be found 106 * buffer - Where the pathname is returned 107 * no_trailing - Remove trailing '_' for each name 108 * segment 109 * 110 * RETURN: Status, Buffer is filled with pathname if status is AE_OK 111 * 112 * DESCRIPTION: Build and return a full namespace pathname 113 * 114 ******************************************************************************/ 115 116 acpi_status 117 acpi_ns_handle_to_pathname(acpi_handle target_handle, 118 struct acpi_buffer * buffer, u8 no_trailing) 119 { 120 acpi_status status; 121 struct acpi_namespace_node *node; 122 acpi_size required_size; 123 124 ACPI_FUNCTION_TRACE_PTR(ns_handle_to_pathname, target_handle); 125 126 node = acpi_ns_validate_handle(target_handle); 127 if (!node) { 128 return_ACPI_STATUS(AE_BAD_PARAMETER); 129 } 130 131 /* Determine size required for the caller buffer */ 132 133 required_size = 134 acpi_ns_build_normalized_path(node, NULL, 0, no_trailing); 135 if (!required_size) { 136 return_ACPI_STATUS(AE_BAD_PARAMETER); 137 } 138 139 /* Validate/Allocate/Clear caller buffer */ 140 141 status = acpi_ut_initialize_buffer(buffer, required_size); 142 if (ACPI_FAILURE(status)) { 143 return_ACPI_STATUS(status); 144 } 145 146 /* Build the path in the caller buffer */ 147 148 (void)acpi_ns_build_normalized_path(node, buffer->pointer, 149 required_size, no_trailing); 150 if (ACPI_FAILURE(status)) { 151 return_ACPI_STATUS(status); 152 } 153 154 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "%s [%X]\n", 155 (char *)buffer->pointer, (u32) required_size)); 156 return_ACPI_STATUS(AE_OK); 157 } 158 159 /******************************************************************************* 160 * 161 * FUNCTION: acpi_ns_build_normalized_path 162 * 163 * PARAMETERS: node - Namespace node 164 * full_path - Where the path name is returned 165 * path_size - Size of returned path name buffer 166 * no_trailing - Remove trailing '_' from each name segment 167 * 168 * RETURN: Return 1 if the AML path is empty, otherwise returning (length 169 * of pathname + 1) which means the 'FullPath' contains a trailing 170 * null. 171 * 172 * DESCRIPTION: Build and return a full namespace pathname. 173 * Note that if the size of 'FullPath' isn't large enough to 174 * contain the namespace node's path name, the actual required 175 * buffer length is returned, and it should be greater than 176 * 'PathSize'. So callers are able to check the returning value 177 * to determine the buffer size of 'FullPath'. 178 * 179 ******************************************************************************/ 180 181 u32 182 acpi_ns_build_normalized_path(struct acpi_namespace_node *node, 183 char *full_path, u32 path_size, u8 no_trailing) 184 { 185 u32 length = 0, i; 186 char name[ACPI_NAME_SIZE]; 187 u8 do_no_trailing; 188 char c, *left, *right; 189 struct acpi_namespace_node *next_node; 190 191 ACPI_FUNCTION_TRACE_PTR(ns_build_normalized_path, node); 192 193 #define ACPI_PATH_PUT8(path, size, byte, length) \ 194 do { \ 195 if ((length) < (size)) \ 196 { \ 197 (path)[(length)] = (byte); \ 198 } \ 199 (length)++; \ 200 } while (0) 201 202 /* 203 * Make sure the path_size is correct, so that we don't need to 204 * validate both full_path and path_size. 205 */ 206 if (!full_path) { 207 path_size = 0; 208 } 209 210 if (!node) { 211 goto build_trailing_null; 212 } 213 214 next_node = node; 215 while (next_node && next_node != acpi_gbl_root_node) { 216 if (next_node != node) { 217 ACPI_PATH_PUT8(full_path, path_size, 218 AML_DUAL_NAME_PREFIX, length); 219 } 220 ACPI_MOVE_32_TO_32(name, &next_node->name); 221 do_no_trailing = no_trailing; 222 for (i = 0; i < 4; i++) { 223 c = name[4 - i - 1]; 224 if (do_no_trailing && c != '_') { 225 do_no_trailing = FALSE; 226 } 227 if (!do_no_trailing) { 228 ACPI_PATH_PUT8(full_path, path_size, c, length); 229 } 230 } 231 next_node = next_node->parent; 232 } 233 ACPI_PATH_PUT8(full_path, path_size, AML_ROOT_PREFIX, length); 234 235 /* Reverse the path string */ 236 237 if (length <= path_size) { 238 left = full_path; 239 right = full_path + length - 1; 240 while (left < right) { 241 c = *left; 242 *left++ = *right; 243 *right-- = c; 244 } 245 } 246 247 /* Append the trailing null */ 248 249 build_trailing_null: 250 ACPI_PATH_PUT8(full_path, path_size, '\0', length); 251 252 #undef ACPI_PATH_PUT8 253 254 return_UINT32(length); 255 } 256 257 /******************************************************************************* 258 * 259 * FUNCTION: acpi_ns_get_normalized_pathname 260 * 261 * PARAMETERS: node - Namespace node whose pathname is needed 262 * no_trailing - Remove trailing '_' from each name segment 263 * 264 * RETURN: Pointer to storage containing the fully qualified name of 265 * the node, In external format (name segments separated by path 266 * separators.) 267 * 268 * DESCRIPTION: Used to obtain the full pathname to a namespace node, usually 269 * for error and debug statements. All trailing '_' will be 270 * removed from the full pathname if 'NoTrailing' is specified.. 271 * 272 ******************************************************************************/ 273 274 char *acpi_ns_get_normalized_pathname(struct acpi_namespace_node *node, 275 u8 no_trailing) 276 { 277 char *name_buffer; 278 acpi_size size; 279 280 ACPI_FUNCTION_TRACE_PTR(ns_get_normalized_pathname, node); 281 282 /* Calculate required buffer size based on depth below root */ 283 284 size = acpi_ns_build_normalized_path(node, NULL, 0, no_trailing); 285 if (!size) { 286 return_PTR(NULL); 287 } 288 289 /* Allocate a buffer to be returned to caller */ 290 291 name_buffer = ACPI_ALLOCATE_ZEROED(size); 292 if (!name_buffer) { 293 ACPI_ERROR((AE_INFO, "Could not allocate %u bytes", (u32)size)); 294 return_PTR(NULL); 295 } 296 297 /* Build the path in the allocated buffer */ 298 299 (void)acpi_ns_build_normalized_path(node, name_buffer, size, 300 no_trailing); 301 302 return_PTR(name_buffer); 303 } 304