1 /* Maintenance of module list in libdwfl. 2 Copyright (C) 2005, 2006, 2007, 2008, 2014, 2015 Red Hat, Inc. 3 This file is part of elfutils. 4 5 This file is free software; you can redistribute it and/or modify 6 it under the terms of either 7 8 * the GNU Lesser General Public License as published by the Free 9 Software Foundation; either version 3 of the License, or (at 10 your option) any later version 11 12 or 13 14 * the GNU General Public License as published by the Free 15 Software Foundation; either version 2 of the License, or (at 16 your option) any later version 17 18 or both in parallel, as here. 19 20 elfutils is distributed in the hope that it will be useful, but 21 WITHOUT ANY WARRANTY; without even the implied warranty of 22 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 23 General Public License for more details. 24 25 You should have received copies of the GNU General Public License and 26 the GNU Lesser General Public License along with this program. If 27 not, see <http://www.gnu.org/licenses/>. */ 28 29 #include "libdwflP.h" 30 #include "../libdw/cfi.h" 31 #include <search.h> 32 #include <unistd.h> 33 34 static void 35 free_cu (struct dwfl_cu *cu) 36 { 37 if (cu->lines != NULL) 38 free (cu->lines); 39 free (cu); 40 } 41 42 static void 43 nofree (void *arg __attribute__ ((unused))) 44 { 45 } 46 47 static void 48 free_file (struct dwfl_file *file) 49 { 50 free (file->name); 51 52 /* Close the fd only on the last reference. */ 53 if (file->elf != NULL && elf_end (file->elf) == 0 && file->fd != -1) 54 close (file->fd); 55 } 56 57 void 58 internal_function 59 __libdwfl_module_free (Dwfl_Module *mod) 60 { 61 if (mod->lazy_cu_root != NULL) 62 tdestroy (mod->lazy_cu_root, nofree); 63 64 if (mod->aranges != NULL) 65 free (mod->aranges); 66 67 if (mod->cu != NULL) 68 { 69 for (size_t i = 0; i < mod->ncu; ++i) 70 free_cu (mod->cu[i]); 71 free (mod->cu); 72 } 73 74 /* We might have primed the Dwarf_CFI ebl cache with our own ebl 75 in __libdwfl_set_cfi. Make sure we don't free it twice. */ 76 if (mod->eh_cfi != NULL) 77 { 78 if (mod->eh_cfi->ebl != NULL && mod->eh_cfi->ebl == mod->ebl) 79 mod->eh_cfi->ebl = NULL; 80 dwarf_cfi_end (mod->eh_cfi); 81 } 82 83 if (mod->dwarf_cfi != NULL) 84 { 85 if (mod->dwarf_cfi->ebl != NULL && mod->dwarf_cfi->ebl == mod->ebl) 86 mod->dwarf_cfi->ebl = NULL; 87 /* We don't need to explicitly destroy the dwarf_cfi. 88 That will be done by dwarf_end. */ 89 } 90 91 if (mod->dw != NULL) 92 { 93 INTUSE(dwarf_end) (mod->dw); 94 if (mod->alt != NULL) 95 { 96 INTUSE(dwarf_end) (mod->alt); 97 if (mod->alt_elf != NULL) 98 elf_end (mod->alt_elf); 99 if (mod->alt_fd != -1) 100 close (mod->alt_fd); 101 } 102 } 103 104 if (mod->ebl != NULL) 105 ebl_closebackend (mod->ebl); 106 107 if (mod->debug.elf != mod->main.elf) 108 free_file (&mod->debug); 109 free_file (&mod->main); 110 free_file (&mod->aux_sym); 111 112 if (mod->build_id_bits != NULL) 113 free (mod->build_id_bits); 114 115 if (mod->reloc_info != NULL) 116 free (mod->reloc_info); 117 118 free (mod->name); 119 free (mod); 120 } 121 122 void 123 dwfl_report_begin_add (Dwfl *dwfl __attribute__ ((unused))) 124 { 125 /* The lookup table will be cleared on demand, there is nothing we need 126 to do here. */ 127 } 128 INTDEF (dwfl_report_begin_add) 129 130 void 131 dwfl_report_begin (Dwfl *dwfl) 132 { 133 /* Clear the segment lookup table. */ 134 dwfl->lookup_elts = 0; 135 136 for (Dwfl_Module *m = dwfl->modulelist; m != NULL; m = m->next) 137 m->gc = true; 138 139 dwfl->offline_next_address = OFFLINE_REDZONE; 140 } 141 INTDEF (dwfl_report_begin) 142 143 static inline Dwfl_Module * 144 use (Dwfl_Module *mod, Dwfl_Module **tailp, Dwfl *dwfl) 145 { 146 mod->next = *tailp; 147 *tailp = mod; 148 149 if (unlikely (dwfl->lookup_module != NULL)) 150 { 151 free (dwfl->lookup_module); 152 dwfl->lookup_module = NULL; 153 } 154 155 return mod; 156 } 157 158 /* Report that a module called NAME spans addresses [START, END). 159 Returns the module handle, either existing or newly allocated, 160 or returns a null pointer for an allocation error. */ 161 Dwfl_Module * 162 dwfl_report_module (Dwfl *dwfl, const char *name, 163 GElf_Addr start, GElf_Addr end) 164 { 165 Dwfl_Module **tailp = &dwfl->modulelist, **prevp = tailp; 166 167 for (Dwfl_Module *m = *prevp; m != NULL; m = *(prevp = &m->next)) 168 { 169 if (m->low_addr == start && m->high_addr == end 170 && !strcmp (m->name, name)) 171 { 172 /* This module is still here. Move it to the place in the list 173 after the last module already reported. */ 174 *prevp = m->next; 175 m->gc = false; 176 return use (m, tailp, dwfl); 177 } 178 179 if (! m->gc) 180 tailp = &m->next; 181 } 182 183 Dwfl_Module *mod = calloc (1, sizeof *mod); 184 if (mod == NULL) 185 goto nomem; 186 187 mod->name = strdup (name); 188 if (mod->name == NULL) 189 { 190 free (mod); 191 nomem: 192 __libdwfl_seterrno (DWFL_E_NOMEM); 193 return NULL; 194 } 195 196 mod->low_addr = start; 197 mod->high_addr = end; 198 mod->dwfl = dwfl; 199 200 return use (mod, tailp, dwfl); 201 } 202 INTDEF (dwfl_report_module) 203 204 205 /* Finish reporting the current set of modules to the library. 206 If REMOVED is not null, it's called for each module that 207 existed before but was not included in the current report. 208 Returns a nonzero return value from the callback. 209 DWFL cannot be used until this function has returned zero. */ 210 int 211 dwfl_report_end (Dwfl *dwfl, 212 int (*removed) (Dwfl_Module *, void *, 213 const char *, Dwarf_Addr, 214 void *arg), 215 void *arg) 216 { 217 Dwfl_Module **tailp = &dwfl->modulelist; 218 while (*tailp != NULL) 219 { 220 Dwfl_Module *m = *tailp; 221 if (m->gc && removed != NULL) 222 { 223 int result = (*removed) (MODCB_ARGS (m), arg); 224 if (result != 0) 225 return result; 226 } 227 if (m->gc) 228 { 229 *tailp = m->next; 230 __libdwfl_module_free (m); 231 } 232 else 233 tailp = &m->next; 234 } 235 236 return 0; 237 } 238 INTDEF (dwfl_report_end) 239
