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/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 return_PTR(name_buffer); 74 } 75 76 /******************************************************************************* 77 * 78 * FUNCTION: acpi_ns_get_pathname_length 79 * 80 * PARAMETERS: node - Namespace node 81 * 82 * RETURN: Length of path, including prefix 83 * 84 * DESCRIPTION: Get the length of the pathname string for this node 85 * 86 ******************************************************************************/ 87 88 acpi_size acpi_ns_get_pathname_length(struct acpi_namespace_node *node) 89 { 90 acpi_size size; 91 92 ACPI_FUNCTION_ENTRY(); 93 94 size = acpi_ns_build_normalized_path(node, NULL, 0, FALSE); 95 return (size); 96 } 97 98 /******************************************************************************* 99 * 100 * FUNCTION: acpi_ns_handle_to_pathname 101 * 102 * PARAMETERS: target_handle - Handle of named object whose name is 103 * to be found 104 * buffer - Where the pathname is returned 105 * no_trailing - Remove trailing '_' for each name 106 * segment 107 * 108 * RETURN: Status, Buffer is filled with pathname if status is AE_OK 109 * 110 * DESCRIPTION: Build and return a full namespace pathname 111 * 112 ******************************************************************************/ 113 114 acpi_status 115 acpi_ns_handle_to_pathname(acpi_handle target_handle, 116 struct acpi_buffer *buffer, u8 no_trailing) 117 { 118 acpi_status status; 119 struct acpi_namespace_node *node; 120 acpi_size required_size; 121 122 ACPI_FUNCTION_TRACE_PTR(ns_handle_to_pathname, target_handle); 123 124 node = acpi_ns_validate_handle(target_handle); 125 if (!node) { 126 return_ACPI_STATUS(AE_BAD_PARAMETER); 127 } 128 129 /* Determine size required for the caller buffer */ 130 131 required_size = 132 acpi_ns_build_normalized_path(node, NULL, 0, no_trailing); 133 if (!required_size) { 134 return_ACPI_STATUS(AE_BAD_PARAMETER); 135 } 136 137 /* Validate/Allocate/Clear caller buffer */ 138 139 status = acpi_ut_initialize_buffer(buffer, required_size); 140 if (ACPI_FAILURE(status)) { 141 return_ACPI_STATUS(status); 142 } 143 144 /* Build the path in the caller buffer */ 145 146 (void)acpi_ns_build_normalized_path(node, buffer->pointer, 147 required_size, no_trailing); 148 if (ACPI_FAILURE(status)) { 149 return_ACPI_STATUS(status); 150 } 151 152 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "%s [%X]\n", 153 (char *)buffer->pointer, (u32) required_size)); 154 return_ACPI_STATUS(AE_OK); 155 } 156 157 /******************************************************************************* 158 * 159 * FUNCTION: acpi_ns_build_normalized_path 160 * 161 * PARAMETERS: node - Namespace node 162 * full_path - Where the path name is returned 163 * path_size - Size of returned path name buffer 164 * no_trailing - Remove trailing '_' from each name segment 165 * 166 * RETURN: Return 1 if the AML path is empty, otherwise returning (length 167 * of pathname + 1) which means the 'FullPath' contains a trailing 168 * null. 169 * 170 * DESCRIPTION: Build and return a full namespace pathname. 171 * Note that if the size of 'FullPath' isn't large enough to 172 * contain the namespace node's path name, the actual required 173 * buffer length is returned, and it should be greater than 174 * 'PathSize'. So callers are able to check the returning value 175 * to determine the buffer size of 'FullPath'. 176 * 177 ******************************************************************************/ 178 179 u32 180 acpi_ns_build_normalized_path(struct acpi_namespace_node *node, 181 char *full_path, u32 path_size, u8 no_trailing) 182 { 183 u32 length = 0, i; 184 char name[ACPI_NAME_SIZE]; 185 u8 do_no_trailing; 186 char c, *left, *right; 187 struct acpi_namespace_node *next_node; 188 189 ACPI_FUNCTION_TRACE_PTR(ns_build_normalized_path, node); 190 191 #define ACPI_PATH_PUT8(path, size, byte, length) \ 192 do { \ 193 if ((length) < (size)) \ 194 { \ 195 (path)[(length)] = (byte); \ 196 } \ 197 (length)++; \ 198 } while (0) 199 200 /* 201 * Make sure the path_size is correct, so that we don't need to 202 * validate both full_path and path_size. 203 */ 204 if (!full_path) { 205 path_size = 0; 206 } 207 208 if (!node) { 209 goto build_trailing_null; 210 } 211 212 next_node = node; 213 while (next_node && next_node != acpi_gbl_root_node) { 214 if (next_node != node) { 215 ACPI_PATH_PUT8(full_path, path_size, 216 AML_DUAL_NAME_PREFIX, length); 217 } 218 219 ACPI_MOVE_32_TO_32(name, &next_node->name); 220 do_no_trailing = no_trailing; 221 for (i = 0; i < 4; i++) { 222 c = name[4 - i - 1]; 223 if (do_no_trailing && c != '_') { 224 do_no_trailing = FALSE; 225 } 226 if (!do_no_trailing) { 227 ACPI_PATH_PUT8(full_path, path_size, c, length); 228 } 229 } 230 231 next_node = next_node->parent; 232 } 233 234 ACPI_PATH_PUT8(full_path, path_size, AML_ROOT_PREFIX, length); 235 236 /* Reverse the path string */ 237 238 if (length <= path_size) { 239 left = full_path; 240 right = full_path + length - 1; 241 242 while (left < right) { 243 c = *left; 244 *left++ = *right; 245 *right-- = c; 246 } 247 } 248 249 /* Append the trailing null */ 250 251 build_trailing_null: 252 ACPI_PATH_PUT8(full_path, path_size, '\0', length); 253 254 #undef ACPI_PATH_PUT8 255 256 return_UINT32(length); 257 } 258 259 /******************************************************************************* 260 * 261 * FUNCTION: acpi_ns_get_normalized_pathname 262 * 263 * PARAMETERS: node - Namespace node whose pathname is needed 264 * no_trailing - Remove trailing '_' from each name segment 265 * 266 * RETURN: Pointer to storage containing the fully qualified name of 267 * the node, In external format (name segments separated by path 268 * separators.) 269 * 270 * DESCRIPTION: Used to obtain the full pathname to a namespace node, usually 271 * for error and debug statements. All trailing '_' will be 272 * removed from the full pathname if 'NoTrailing' is specified.. 273 * 274 ******************************************************************************/ 275 276 char *acpi_ns_get_normalized_pathname(struct acpi_namespace_node *node, 277 u8 no_trailing) 278 { 279 char *name_buffer; 280 acpi_size size; 281 282 ACPI_FUNCTION_TRACE_PTR(ns_get_normalized_pathname, node); 283 284 /* Calculate required buffer size based on depth below root */ 285 286 size = acpi_ns_build_normalized_path(node, NULL, 0, no_trailing); 287 if (!size) { 288 return_PTR(NULL); 289 } 290 291 /* Allocate a buffer to be returned to caller */ 292 293 name_buffer = ACPI_ALLOCATE_ZEROED(size); 294 if (!name_buffer) { 295 ACPI_ERROR((AE_INFO, "Could not allocate %u bytes", (u32)size)); 296 return_PTR(NULL); 297 } 298 299 /* Build the path in the allocated buffer */ 300 301 (void)acpi_ns_build_normalized_path(node, name_buffer, size, 302 no_trailing); 303 304 return_PTR(name_buffer); 305 } 306