1 /****************************************************************************** 2 * 3 * Module Name: dtutils.c - Utility routines for the data table compiler 4 * 5 *****************************************************************************/ 6 7 /* 8 * Copyright (C) 2000 - 2023, 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 MERCHANTABILITY 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 "aslcompiler.h" 45 #include "actables.h" 46 47 #define _COMPONENT DT_COMPILER 48 ACPI_MODULE_NAME ("dtutils") 49 50 /* Local prototypes */ 51 52 static void 53 DtSum ( 54 DT_SUBTABLE *Subtable, 55 void *Context, 56 void *ReturnValue); 57 58 59 /****************************************************************************** 60 * 61 * FUNCTION: DtError 62 * 63 * PARAMETERS: Level - Seriousness (Warning/error, etc.) 64 * MessageId - Index into global message buffer 65 * Op - Parse node where error happened 66 * ExtraMessage - additional error message 67 * 68 * RETURN: None 69 * 70 * DESCRIPTION: Common error interface for data table compiler 71 * 72 *****************************************************************************/ 73 74 void 75 DtError ( 76 UINT8 Level, 77 UINT16 MessageId, 78 DT_FIELD *FieldObject, 79 char *ExtraMessage) 80 { 81 UINT32 Line = 0; 82 83 84 /* Field object could be NULL */ 85 86 if (FieldObject) 87 { 88 Line = FieldObject->Line; 89 } 90 91 /* Check if user wants to ignore this exception */ 92 93 if (AslIsExceptionIgnored (AslGbl_Files[ASL_FILE_INPUT].Filename, 94 Line, Level, MessageId)) 95 { 96 return; 97 } 98 99 if (FieldObject) 100 { 101 AslCommonError (Level, MessageId, 102 FieldObject->Line, 103 FieldObject->Line, 104 FieldObject->ByteOffset, 105 FieldObject->Column, 106 AslGbl_Files[ASL_FILE_INPUT].Filename, ExtraMessage); 107 } 108 else 109 { 110 AslCommonError (Level, MessageId, 0, 111 0, 0, 0, 0, ExtraMessage); 112 } 113 } 114 115 116 /****************************************************************************** 117 * 118 * FUNCTION: DtNameError 119 * 120 * PARAMETERS: Level - Seriousness (Warning/error, etc.) 121 * MessageId - Index into global message buffer 122 * Op - Parse node where error happened 123 * ExtraMessage - additional error message 124 * 125 * RETURN: None 126 * 127 * DESCRIPTION: Error interface for named objects 128 * 129 *****************************************************************************/ 130 131 void 132 DtNameError ( 133 UINT8 Level, 134 UINT16 MessageId, 135 DT_FIELD *FieldObject, 136 char *ExtraMessage) 137 { 138 139 switch (Level) 140 { 141 case ASL_WARNING2: 142 case ASL_WARNING3: 143 144 if (AslGbl_WarningLevel < Level) 145 { 146 return; 147 } 148 break; 149 150 default: 151 152 break; 153 } 154 155 if (FieldObject) 156 { 157 AslCommonError (Level, MessageId, 158 FieldObject->Line, 159 FieldObject->Line, 160 FieldObject->ByteOffset, 161 FieldObject->NameColumn, 162 AslGbl_Files[ASL_FILE_INPUT].Filename, ExtraMessage); 163 } 164 else 165 { 166 AslCommonError (Level, MessageId, 0, 167 0, 0, 0, 0, ExtraMessage); 168 } 169 } 170 171 172 /******************************************************************************* 173 * 174 * FUNCTION: DtFatal 175 * 176 * PARAMETERS: None 177 * 178 * RETURN: None 179 * 180 * DESCRIPTION: Dump the error log and abort the compiler. Used for serious 181 * compile or I/O errors 182 * 183 ******************************************************************************/ 184 185 void 186 DtFatal ( 187 UINT16 MessageId, 188 DT_FIELD *FieldObject, 189 char *ExtraMessage) 190 { 191 192 DtError (ASL_ERROR, MessageId, FieldObject, ExtraMessage); 193 194 /* 195 * TBD: remove this entire function, DtFatal 196 * 197 * We cannot abort the compiler on error, because we may be compiling a 198 * list of files. We must move on to the next file. 199 */ 200 #ifdef __OBSOLETE 201 CmCleanupAndExit (); 202 exit (1); 203 #endif 204 } 205 206 207 /******************************************************************************* 208 * 209 * FUNCTION: DtDoConstant 210 * 211 * PARAMETERS: String - Only hex constants are supported, 212 * regardless of whether the 0x prefix 213 * is used 214 * 215 * RETURN: Converted Integer 216 * 217 * DESCRIPTION: Convert a string to an integer, with overflow/error checking. 218 * 219 ******************************************************************************/ 220 221 UINT64 222 DtDoConstant ( 223 char *String) 224 { 225 UINT64 ConvertedInteger; 226 227 228 /* 229 * TBD: The ImplicitStrtoul64 function does not report overflow 230 * conditions. The input string is simply truncated. If it is 231 * desired to report overflow to the table compiler, this should 232 * somehow be added here. Note: integers that are prefixed with 0x 233 * or not are both hex integers. 234 */ 235 ConvertedInteger = AcpiUtImplicitStrtoul64 (String); 236 return (ConvertedInteger); 237 } 238 239 /****************************************************************************** 240 * 241 * FUNCTION: DtGetFieldValue 242 * 243 * PARAMETERS: Field - Current field list pointer 244 * 245 * RETURN: Field value 246 * 247 * DESCRIPTION: Get field value 248 * 249 *****************************************************************************/ 250 251 char * 252 DtGetFieldValue ( 253 DT_FIELD *Field) 254 { 255 if (!Field) 256 { 257 return (NULL); 258 } 259 260 return (Field->Value); 261 } 262 263 264 /****************************************************************************** 265 * 266 * FUNCTION: DtGetFieldType 267 * 268 * PARAMETERS: Info - Data table info 269 * 270 * RETURN: Field type 271 * 272 * DESCRIPTION: Get field type 273 * 274 *****************************************************************************/ 275 276 UINT8 277 DtGetFieldType ( 278 ACPI_DMTABLE_INFO *Info) 279 { 280 UINT8 Type; 281 282 283 /* DT_FLAG means that this is the start of a block of flag bits */ 284 /* TBD - we can make these a separate opcode later */ 285 286 if (Info->Flags & DT_FLAG) 287 { 288 return (DT_FIELD_TYPE_FLAGS_INTEGER); 289 } 290 291 /* Type is based upon the opcode for this field in the info table */ 292 293 switch (Info->Opcode) 294 { 295 case ACPI_DMT_FLAG0: 296 case ACPI_DMT_FLAG1: 297 case ACPI_DMT_FLAG2: 298 case ACPI_DMT_FLAG3: 299 case ACPI_DMT_FLAG4: 300 case ACPI_DMT_FLAG5: 301 case ACPI_DMT_FLAG6: 302 case ACPI_DMT_FLAG7: 303 case ACPI_DMT_FLAGS0: 304 case ACPI_DMT_FLAGS1: 305 case ACPI_DMT_FLAGS2: 306 case ACPI_DMT_FLAGS8_2: 307 case ACPI_DMT_FLAGS4: 308 case ACPI_DMT_FLAGS4_0: 309 case ACPI_DMT_FLAGS4_4: 310 case ACPI_DMT_FLAGS4_8: 311 case ACPI_DMT_FLAGS4_12: 312 case ACPI_DMT_FLAGS16_16: 313 314 Type = DT_FIELD_TYPE_FLAG; 315 break; 316 317 case ACPI_DMT_NAME4: 318 case ACPI_DMT_SIG: 319 case ACPI_DMT_NAME6: 320 case ACPI_DMT_NAME8: 321 case ACPI_DMT_STRING: 322 case ACPI_DMT_IVRS_UNTERMINATED_STRING: 323 324 Type = DT_FIELD_TYPE_STRING; 325 break; 326 327 case ACPI_DMT_BUFFER: 328 case ACPI_DMT_RAW_BUFFER: 329 case ACPI_DMT_BUF7: 330 case ACPI_DMT_BUF10: 331 case ACPI_DMT_BUF12: 332 case ACPI_DMT_BUF16: 333 case ACPI_DMT_BUF18: 334 case ACPI_DMT_BUF128: 335 case ACPI_DMT_PCI_PATH: 336 case ACPI_DMT_PMTT_VENDOR: 337 338 Type = DT_FIELD_TYPE_BUFFER; 339 break; 340 341 case ACPI_DMT_GAS: 342 case ACPI_DMT_HESTNTFY: 343 case ACPI_DMT_IORTMEM: 344 345 Type = DT_FIELD_TYPE_INLINE_SUBTABLE; 346 break; 347 348 case ACPI_DMT_UNICODE: 349 case ACPI_DMT_WPBT_UNICODE: 350 351 Type = DT_FIELD_TYPE_UNICODE; 352 break; 353 354 case ACPI_DMT_UUID: 355 356 Type = DT_FIELD_TYPE_UUID; 357 break; 358 359 case ACPI_DMT_DEVICE_PATH: 360 361 Type = DT_FIELD_TYPE_DEVICE_PATH; 362 break; 363 364 case ACPI_DMT_LABEL: 365 366 Type = DT_FIELD_TYPE_LABEL; 367 break; 368 369 default: 370 371 Type = DT_FIELD_TYPE_INTEGER; 372 break; 373 } 374 375 return (Type); 376 } 377 378 379 /****************************************************************************** 380 * 381 * FUNCTION: DtGetBufferLength 382 * 383 * PARAMETERS: Buffer - List of integers, 384 * for example "10 3A 4F 2E" 385 * 386 * RETURN: Count of integer 387 * 388 * DESCRIPTION: Get length of bytes needed to store the integers 389 * 390 *****************************************************************************/ 391 392 UINT32 393 DtGetBufferLength ( 394 char *Buffer) 395 { 396 UINT32 ByteLength = 0; 397 398 399 while (*Buffer) 400 { 401 if (*Buffer == ' ') 402 { 403 ByteLength++; 404 405 while (*Buffer == ' ') 406 { 407 Buffer++; 408 } 409 } 410 411 Buffer++; 412 } 413 414 return (++ByteLength); 415 } 416 417 418 /****************************************************************************** 419 * 420 * FUNCTION: DtGetFieldLength 421 * 422 * PARAMETERS: Field - Current field 423 * Info - Data table info 424 * 425 * RETURN: Field length 426 * 427 * DESCRIPTION: Get length of bytes needed to compile the field 428 * 429 * Note: This function must remain in sync with AcpiDmDumpTable. 430 * 431 *****************************************************************************/ 432 433 UINT32 434 DtGetFieldLength ( 435 DT_FIELD *Field, 436 ACPI_DMTABLE_INFO *Info) 437 { 438 UINT32 ByteLength = 0; 439 char *Value; 440 441 442 /* Length is based upon the opcode for this field in the info table */ 443 444 switch (Info->Opcode) 445 { 446 case ACPI_DMT_FLAG0: 447 case ACPI_DMT_FLAG1: 448 case ACPI_DMT_FLAG2: 449 case ACPI_DMT_FLAG3: 450 case ACPI_DMT_FLAG4: 451 case ACPI_DMT_FLAG5: 452 case ACPI_DMT_FLAG6: 453 case ACPI_DMT_FLAG7: 454 case ACPI_DMT_FLAGS0: 455 case ACPI_DMT_FLAGS1: 456 case ACPI_DMT_FLAGS2: 457 case ACPI_DMT_FLAGS8_2: 458 case ACPI_DMT_FLAGS4: 459 case ACPI_DMT_FLAGS4_0: 460 case ACPI_DMT_FLAGS4_4: 461 case ACPI_DMT_FLAGS4_8: 462 case ACPI_DMT_FLAGS4_12: 463 case ACPI_DMT_FLAGS16_16: 464 case ACPI_DMT_LABEL: 465 case ACPI_DMT_EXTRA_TEXT: 466 467 ByteLength = 0; 468 break; 469 470 case ACPI_DMT_UINT8: 471 case ACPI_DMT_CHKSUM: 472 case ACPI_DMT_SPACEID: 473 case ACPI_DMT_ACCWIDTH: 474 case ACPI_DMT_CEDT: 475 case ACPI_DMT_IVRS: 476 case ACPI_DMT_IVRS_DE: 477 case ACPI_DMT_GTDT: 478 case ACPI_DMT_MADT: 479 case ACPI_DMT_MPAM_LOCATOR: 480 case ACPI_DMT_NHLT1: 481 case ACPI_DMT_NHLT1a: 482 case ACPI_DMT_NHLT1b: 483 case ACPI_DMT_NHLT1c: 484 case ACPI_DMT_NHLT1d: 485 case ACPI_DMT_NHLT1f: 486 case ACPI_DMT_PCCT: 487 case ACPI_DMT_PMTT: 488 case ACPI_DMT_PPTT: 489 case ACPI_DMT_RGRT: 490 case ACPI_DMT_SDEV: 491 case ACPI_DMT_SRAT: 492 case ACPI_DMT_AEST: 493 case ACPI_DMT_AEST_RES: 494 case ACPI_DMT_AEST_XFACE: 495 case ACPI_DMT_AEST_XRUPT: 496 case ACPI_DMT_ASF: 497 case ACPI_DMT_CDAT: 498 case ACPI_DMT_HESTNTYP: 499 case ACPI_DMT_FADTPM: 500 case ACPI_DMT_EINJACT: 501 case ACPI_DMT_EINJINST: 502 case ACPI_DMT_ERSTACT: 503 case ACPI_DMT_ERSTINST: 504 case ACPI_DMT_DMAR_SCOPE: 505 case ACPI_DMT_VIOT: 506 507 ByteLength = 1; 508 break; 509 510 case ACPI_DMT_ASPT: 511 case ACPI_DMT_UINT16: 512 case ACPI_DMT_DMAR: 513 case ACPI_DMT_HEST: 514 case ACPI_DMT_HMAT: 515 case ACPI_DMT_NFIT: 516 case ACPI_DMT_NHLT1e: 517 case ACPI_DMT_PCI_PATH: 518 case ACPI_DMT_PHAT: 519 520 ByteLength = 2; 521 break; 522 523 case ACPI_DMT_UINT24: 524 525 ByteLength = 3; 526 break; 527 528 case ACPI_DMT_UINT32: 529 case ACPI_DMT_AEST_CACHE: 530 case ACPI_DMT_AEST_GIC: 531 case ACPI_DMT_NAME4: 532 case ACPI_DMT_SIG: 533 case ACPI_DMT_LPIT: 534 case ACPI_DMT_TPM2: 535 536 ByteLength = 4; 537 break; 538 539 case ACPI_DMT_UINT40: 540 541 ByteLength = 5; 542 break; 543 544 case ACPI_DMT_UINT48: 545 case ACPI_DMT_NAME6: 546 547 ByteLength = 6; 548 break; 549 550 case ACPI_DMT_UINT56: 551 case ACPI_DMT_BUF7: 552 553 ByteLength = 7; 554 break; 555 556 case ACPI_DMT_UINT64: 557 case ACPI_DMT_NAME8: 558 559 ByteLength = 8; 560 break; 561 562 case ACPI_DMT_STRING: 563 564 Value = DtGetFieldValue (Field); 565 if (Value) 566 { 567 ByteLength = strlen (Value) + 1; 568 } 569 else 570 { /* At this point, this is a fatal error */ 571 572 snprintf (AslGbl_MsgBuffer, sizeof(AslGbl_MsgBuffer), "Expected \"%s\"", Info->Name); 573 DtFatal (ASL_MSG_COMPILER_INTERNAL, NULL, AslGbl_MsgBuffer); 574 return (0); 575 } 576 break; 577 578 case ACPI_DMT_IVRS_UNTERMINATED_STRING: 579 580 Value = DtGetFieldValue (Field); 581 if (Value) 582 { 583 ByteLength = strlen (Value); 584 } 585 else 586 { /* At this point, this is a fatal error */ 587 588 snprintf (AslGbl_MsgBuffer, sizeof(AslGbl_MsgBuffer), "Expected \"%s\"", Info->Name); 589 DtFatal (ASL_MSG_COMPILER_INTERNAL, NULL, AslGbl_MsgBuffer); 590 return (0); 591 } 592 break; 593 594 case ACPI_DMT_GAS: 595 596 ByteLength = sizeof (ACPI_GENERIC_ADDRESS); 597 break; 598 599 case ACPI_DMT_HESTNTFY: 600 601 ByteLength = sizeof (ACPI_HEST_NOTIFY); 602 break; 603 604 case ACPI_DMT_IORTMEM: 605 606 ByteLength = sizeof (ACPI_IORT_MEMORY_ACCESS); 607 break; 608 609 case ACPI_DMT_BUFFER: 610 case ACPI_DMT_RAW_BUFFER: 611 case ACPI_DMT_PMTT_VENDOR: 612 613 Value = DtGetFieldValue (Field); 614 if (Value) 615 { 616 ByteLength = DtGetBufferLength (Value); 617 } 618 else 619 { /* At this point, this is a fatal error */ 620 621 snprintf (AslGbl_MsgBuffer, sizeof(AslGbl_MsgBuffer), "Expected \"%s\"", Info->Name); 622 DtFatal (ASL_MSG_COMPILER_INTERNAL, NULL, AslGbl_MsgBuffer); 623 return (0); 624 } 625 break; 626 627 case ACPI_DMT_BUF10: 628 629 ByteLength = 10; 630 break; 631 632 case ACPI_DMT_BUF12: 633 634 ByteLength = 12; 635 break; 636 637 case ACPI_DMT_BUF16: 638 case ACPI_DMT_UUID: 639 640 ByteLength = 16; 641 break; 642 643 case ACPI_DMT_BUF18: 644 645 ByteLength = 18; 646 break; 647 648 case ACPI_DMT_BUF128: 649 650 ByteLength = 128; 651 break; 652 653 case ACPI_DMT_UNICODE: 654 case ACPI_DMT_WPBT_UNICODE: 655 656 Value = DtGetFieldValue (Field); 657 658 /* TBD: error if Value is NULL? (as below?) */ 659 660 ByteLength = (strlen (Value) + 1) * sizeof (UINT16); 661 break; 662 663 default: 664 665 DtFatal (ASL_MSG_COMPILER_INTERNAL, Field, "Invalid table opcode"); 666 return (0); 667 } 668 669 return (ByteLength); 670 } 671 672 673 /****************************************************************************** 674 * 675 * FUNCTION: DtSum 676 * 677 * PARAMETERS: DT_WALK_CALLBACK: 678 * Subtable - Subtable 679 * Context - Unused 680 * ReturnValue - Store the checksum of subtable 681 * 682 * RETURN: Status 683 * 684 * DESCRIPTION: Get the checksum of subtable 685 * 686 *****************************************************************************/ 687 688 static void 689 DtSum ( 690 DT_SUBTABLE *Subtable, 691 void *Context, 692 void *ReturnValue) 693 { 694 UINT8 Checksum; 695 UINT8 *Sum = ReturnValue; 696 697 698 Checksum = AcpiUtChecksum (Subtable->Buffer, Subtable->Length); 699 *Sum = (UINT8) (*Sum + Checksum); 700 } 701 702 703 /****************************************************************************** 704 * 705 * FUNCTION: DtSetTableChecksum 706 * 707 * PARAMETERS: ChecksumPointer - Where to return the checksum 708 * 709 * RETURN: None 710 * 711 * DESCRIPTION: Set checksum of the whole data table into the checksum field 712 * 713 *****************************************************************************/ 714 715 void 716 DtSetTableChecksum ( 717 UINT8 *ChecksumPointer) 718 { 719 UINT8 Checksum = 0; 720 UINT8 OldSum; 721 722 723 DtWalkTableTree (AslGbl_RootTable, DtSum, NULL, &Checksum); 724 725 OldSum = *ChecksumPointer; 726 Checksum = (UINT8) (Checksum - OldSum); 727 728 /* Compute the final checksum */ 729 730 Checksum = (UINT8) (0 - Checksum); 731 *ChecksumPointer = Checksum; 732 } 733 734 735 /****************************************************************************** 736 * 737 * FUNCTION: DtSetTableLength 738 * 739 * PARAMETERS: None 740 * 741 * RETURN: None 742 * 743 * DESCRIPTION: Walk the subtables and set all the length fields 744 * 745 *****************************************************************************/ 746 747 void 748 DtSetTableLength ( 749 void) 750 { 751 DT_SUBTABLE *ParentTable; 752 DT_SUBTABLE *ChildTable; 753 754 755 ParentTable = AslGbl_RootTable; 756 ChildTable = NULL; 757 758 if (!ParentTable) 759 { 760 return; 761 } 762 763 DtSetSubtableLength (ParentTable); 764 765 while (1) 766 { 767 ChildTable = DtGetNextSubtable (ParentTable, ChildTable); 768 if (ChildTable) 769 { 770 if (ChildTable->LengthField) 771 { 772 DtSetSubtableLength (ChildTable); 773 } 774 775 if (ChildTable->Child) 776 { 777 ParentTable = ChildTable; 778 ChildTable = NULL; 779 } 780 else 781 { 782 ParentTable->TotalLength += ChildTable->TotalLength; 783 if (ParentTable->LengthField) 784 { 785 DtSetSubtableLength (ParentTable); 786 } 787 } 788 } 789 else 790 { 791 ChildTable = ParentTable; 792 793 if (ChildTable == AslGbl_RootTable) 794 { 795 break; 796 } 797 798 ParentTable = DtGetParentSubtable (ParentTable); 799 800 ParentTable->TotalLength += ChildTable->TotalLength; 801 if (ParentTable->LengthField) 802 { 803 DtSetSubtableLength (ParentTable); 804 } 805 } 806 } 807 } 808 809 810 /****************************************************************************** 811 * 812 * FUNCTION: DtWalkTableTree 813 * 814 * PARAMETERS: StartTable - Subtable in the tree where walking begins 815 * UserFunction - Called during the walk 816 * Context - Passed to user function 817 * ReturnValue - The return value of UserFunction 818 * 819 * RETURN: None 820 * 821 * DESCRIPTION: Performs a depth-first walk of the subtable tree 822 * 823 *****************************************************************************/ 824 825 void 826 DtWalkTableTree ( 827 DT_SUBTABLE *StartTable, 828 DT_WALK_CALLBACK UserFunction, 829 void *Context, 830 void *ReturnValue) 831 { 832 DT_SUBTABLE *ParentTable; 833 DT_SUBTABLE *ChildTable; 834 835 836 ParentTable = StartTable; 837 ChildTable = NULL; 838 839 if (!ParentTable) 840 { 841 return; 842 } 843 844 UserFunction (ParentTable, Context, ReturnValue); 845 846 while (1) 847 { 848 ChildTable = DtGetNextSubtable (ParentTable, ChildTable); 849 if (ChildTable) 850 { 851 UserFunction (ChildTable, Context, ReturnValue); 852 853 if (ChildTable->Child) 854 { 855 ParentTable = ChildTable; 856 ChildTable = NULL; 857 } 858 } 859 else 860 { 861 ChildTable = ParentTable; 862 if (ChildTable == AslGbl_RootTable) 863 { 864 break; 865 } 866 867 ParentTable = DtGetParentSubtable (ParentTable); 868 869 if (ChildTable->Peer == StartTable) 870 { 871 break; 872 } 873 } 874 } 875 } 876