Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame^] | 1 | /* Return die at given offset. |
| 2 | Copyright (C) 2000, 2002 Red Hat, Inc. |
| 3 | Written by Ulrich Drepper <drepper@redhat.com>, 2000. |
| 4 | |
| 5 | This program is Open Source software; you can redistribute it and/or |
| 6 | modify it under the terms of the Open Software License version 1.0 as |
| 7 | published by the Open Source Initiative. |
| 8 | |
| 9 | You should have received a copy of the Open Software License along |
| 10 | with this program; if not, you may obtain a copy of the Open Software |
| 11 | License version 1.0 from http://www.opensource.org/licenses/osl.php or |
| 12 | by writing the Open Source Initiative c/o Lawrence Rosen, Esq., |
| 13 | 3001 King Ranch Road, Ukiah, CA 95482. */ |
| 14 | |
| 15 | #ifdef HAVE_CONFIG_H |
| 16 | # include <config.h> |
| 17 | #endif |
| 18 | |
| 19 | #include <dwarf.h> |
| 20 | #include <stdlib.h> |
| 21 | |
| 22 | #include <libdwarfP.h> |
| 23 | |
| 24 | |
| 25 | /* XXX This function will have to be optimized. The search is too linear |
| 26 | to be performed too often -> O(n²). */ |
| 27 | static Dwarf_CU_Info |
| 28 | find_cu (Dwarf_Debug dbg, Dwarf_Off offset, Dwarf_Error *error) |
| 29 | { |
| 30 | Dwarf_CU_Info cu; |
| 31 | Dwarf_Word cu_offset; |
| 32 | |
| 33 | /* Search in the CUs already known. */ |
| 34 | for (cu = dbg->cu_list; cu != NULL; cu = cu->next) |
| 35 | if (cu->offset <= offset |
| 36 | && cu->offset + 2 * cu->offset_size - 4 + cu->length > offset) |
| 37 | return cu; |
| 38 | |
| 39 | /* The CU is not yet loaded. Do this now. */ |
| 40 | if (dbg->cu_list_tail == NULL) |
| 41 | cu_offset = 0; |
| 42 | else |
| 43 | cu_offset = (dbg->cu_list_tail->offset |
| 44 | + 2 * dbg->cu_list_tail->offset_size - 4 |
| 45 | + dbg->cu_list_tail->length); |
| 46 | |
| 47 | while (1) |
| 48 | { |
| 49 | /* Get next CU and add it to the end of the list. */ |
| 50 | if (__libdwarf_get_cu_at_offset (dbg, cu_offset, &cu, error) |
| 51 | != DW_DLV_OK) |
| 52 | return NULL; |
| 53 | |
| 54 | /* Offset of next CU. */ |
| 55 | cu_offset += 2 * cu->offset_size - 4 + cu->length; |
| 56 | |
| 57 | /* If this the CU we are looking for? */ |
| 58 | if (offset < cu_offset) |
| 59 | return cu; |
| 60 | } |
| 61 | } |
| 62 | |
| 63 | |
| 64 | int |
| 65 | dwarf_offdie (dbg, offset, return_die, error) |
| 66 | Dwarf_Debug dbg; |
| 67 | Dwarf_Off offset; |
| 68 | Dwarf_Die *return_die; |
| 69 | Dwarf_Error *error; |
| 70 | { |
| 71 | Dwarf_CU_Info cu; |
| 72 | Dwarf_Die new_die; |
| 73 | Dwarf_Small *die_addr; |
| 74 | Dwarf_Word u128; |
| 75 | |
| 76 | if (offset >= dbg->sections[IDX_debug_info].size) |
| 77 | { |
| 78 | /* Completely out of bounds. */ |
| 79 | __libdwarf_error (dbg, error, DW_E_INVALID_OFFSET); |
| 80 | return DW_DLV_ERROR; |
| 81 | } |
| 82 | |
| 83 | /* Find the compile unit this address belongs to. */ |
| 84 | cu = find_cu (dbg, offset, error); |
| 85 | if (cu == NULL) |
| 86 | return DW_DLV_ERROR; |
| 87 | |
| 88 | /* Creata a new die. */ |
| 89 | new_die = (Dwarf_Die) malloc (sizeof (struct Dwarf_Die_s)); |
| 90 | if (new_die == NULL) |
| 91 | { |
| 92 | __libdwarf_error (dbg, error, DW_E_NOMEM); |
| 93 | return DW_DLV_ERROR; |
| 94 | } |
| 95 | |
| 96 | #ifdef DWARF_DEBUG |
| 97 | new_die->memtag = DW_DLA_DIE; |
| 98 | #endif |
| 99 | |
| 100 | /* Remember the address. */ |
| 101 | die_addr = (Dwarf_Small *) dbg->sections[IDX_debug_info].addr + offset; |
| 102 | new_die->addr = die_addr; |
| 103 | |
| 104 | /* And the compile unit. */ |
| 105 | new_die->cu = cu; |
| 106 | |
| 107 | /* 7.5.2 Debugging Information Entry |
| 108 | |
| 109 | Each debugging information entry begins with an unsigned LEB128 |
| 110 | number containing the abbreviation code for the entry. */ |
| 111 | get_uleb128 (u128, die_addr); |
| 112 | |
| 113 | /* Find the abbreviation. */ |
| 114 | new_die->abbrev = __libdwarf_get_abbrev (dbg, cu, u128, error); |
| 115 | if (new_die->abbrev == NULL) |
| 116 | { |
| 117 | free (new_die); |
| 118 | return DW_DLV_ERROR; |
| 119 | } |
| 120 | |
| 121 | *return_die = new_die; |
| 122 | return DW_DLV_OK; |
| 123 | } |