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1 : : /* Return sibling of given DIE. 2 : : Copyright (C) 2003-2010, 2014, 2015 Red Hat, Inc. 3 : : This file is part of elfutils. 4 : : Written by Ulrich Drepper <drepper@redhat.com>, 2003. 5 : : 6 : : This file is free software; you can redistribute it and/or modify 7 : : it under the terms of either 8 : : 9 : : * the GNU Lesser General Public License as published by the Free 10 : : Software Foundation; either version 3 of the License, or (at 11 : : your option) any later version 12 : : 13 : : or 14 : : 15 : : * the GNU General Public License as published by the Free 16 : : Software Foundation; either version 2 of the License, or (at 17 : : your option) any later version 18 : : 19 : : or both in parallel, as here. 20 : : 21 : : elfutils is distributed in the hope that it will be useful, but 22 : : WITHOUT ANY WARRANTY; without even the implied warranty of 23 : : MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 24 : : General Public License for more details. 25 : : 26 : : You should have received copies of the GNU General Public License and 27 : : the GNU Lesser General Public License along with this program. If 28 : : not, see <http://www.gnu.org/licenses/>. */ 29 : : 30 : : #ifdef HAVE_CONFIG_H 31 : : # include <config.h> 32 : : #endif 33 : : 34 : : #include "libdwP.h" 35 : : #include <dwarf.h> 36 : : #include <string.h> 37 : : 38 : : 39 : : int 40 : 24255970 : dwarf_siblingof (Dwarf_Die *die, Dwarf_Die *result) 41 : : { 42 : : /* Ignore previous errors. */ 43 [ - + ]: 24255970 : if (die == NULL) 44 : : return -1; 45 : : 46 : : /* result is declared NN */ 47 : : 48 [ + + ]: 24255970 : if (result != die) 49 : 2573306 : result->addr = NULL; 50 : : 51 : 24255970 : unsigned int level = 0; 52 : : 53 : : /* Copy of the current DIE. */ 54 : 24255970 : Dwarf_Die this_die = *die; 55 : : /* Temporary attributes we create. */ 56 : 24255970 : Dwarf_Attribute sibattr; 57 : : /* Copy of the CU in the request. */ 58 : 24255970 : sibattr.cu = this_die.cu; 59 : : /* That's the address we start looking. */ 60 : 30152086 : unsigned char *addr; 61 : : 62 : : /* Search for the beginning of the next die on this level. We 63 : : must not return the dies for children of the given die. */ 64 : 30152086 : do 65 : : { 66 : : /* Find the end of the DIE or the sibling attribute. */ 67 : 30152086 : addr = __libdw_find_attr (&this_die, DW_AT_sibling, &sibattr.code, 68 : : &sibattr.form); 69 [ + + + + ]: 30152086 : if (addr != NULL && sibattr.code == DW_AT_sibling) 70 : 4848380 : { 71 : 4848380 : Dwarf_Off offset; 72 : 4848380 : sibattr.valp = addr; 73 [ + - ]: 4848380 : if (unlikely (__libdw_formref (&sibattr, &offset) != 0)) 74 : : /* Something went wrong. */ 75 : 0 : return -1; 76 : : 77 : : /* The sibling attribute should point after this DIE in the CU. 78 : : But not after the end of the CU. */ 79 : 4848380 : size_t size = sibattr.cu->endp - sibattr.cu->startp; 80 : 4848380 : size_t die_off = this_die.addr - this_die.cu->startp; 81 [ + - - + ]: 4848380 : if (unlikely (offset >= size || offset <= die_off)) 82 : : { 83 : 0 : __libdw_seterrno (DWARF_E_INVALID_DWARF); 84 : 0 : return -1; 85 : : } 86 : : 87 : : /* Compute the next address. */ 88 : 4848380 : addr = sibattr.cu->startp + offset; 89 : : } 90 [ + + ]: 25303706 : else if (unlikely (addr == NULL) 91 [ - + ]: 25301414 : || unlikely (this_die.abbrev == DWARF_END_ABBREV)) 92 : : return -1; 93 [ + + ]: 25301414 : else if (this_die.abbrev->has_children) 94 : : /* This abbreviation has children. */ 95 : 1917178 : ++level; 96 : : 97 : : /* End of the buffer. */ 98 : 30149794 : unsigned char *endp = sibattr.cu->endp; 99 : : 100 : 33984150 : while (1) 101 : : { 102 : : /* Make sure we are still in range. Some producers might skip 103 : : the trailing NUL bytes. */ 104 [ + + ]: 32066972 : if (addr >= endp) 105 : : return 1; 106 : : 107 [ + + ]: 32058772 : if (*addr != '\0') 108 : : break; 109 : : 110 [ + + ]: 5340698 : if (level-- == 0) 111 : : { 112 [ + + ]: 3423520 : if (result != die) 113 : 350954 : result->addr = addr; 114 : : /* No more sibling at all. */ 115 : 3423520 : return 1; 116 : : } 117 : : 118 : 1917178 : ++addr; 119 : : } 120 : : 121 : : /* Initialize the 'current DIE'. */ 122 : 26718074 : this_die.addr = addr; 123 : 26718074 : this_die.abbrev = NULL; 124 : : } 125 [ + + ]: 26718074 : while (level > 0); 126 : : 127 : : /* Maybe we reached the end of the CU. */ 128 : 20821958 : unsigned char *endp = sibattr.cu->endp; 129 : 20821958 : if (addr >= endp) 130 : : return 1; 131 : : 132 : : /* Clear the entire DIE structure. This signals we have not yet 133 : : determined any of the information. */ 134 : 20821958 : memset (result, '\0', sizeof (Dwarf_Die)); 135 : : 136 : : /* We have the address. */ 137 : 20821958 : result->addr = addr; 138 : : 139 : : /* Same CU as the parent. */ 140 : 20821958 : result->cu = sibattr.cu; 141 : : 142 : 20821958 : return 0; 143 : : } 144 : : INTDEF(dwarf_siblingof)