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 #ifdef HAVE_CONFIG_H 30 # include <config.h> 31 #endif 32 33 #include "libdwflP.h" 34 #include "../libdw/cfi.h" 35 #include <search.h> 36 #include <unistd.h> 37 38 static void 39 free_cu (struct dwfl_cu *cu) 40 { 41 if (cu->lines != NULL) 42 free (cu->lines); 43 free (cu); 44 } 45 46 static void 47 nofree (void *arg __attribute__ ((unused))) 48 { 49 } 50 51 static void 52 free_file (struct dwfl_file *file) 53 { 54 free (file->name); 55 56 /* Close the fd only on the last reference. */ 57 if (file->elf != NULL && elf_end (file->elf) == 0 && file->fd != -1) 58 close (file->fd); 59 } 60 61 void 62 internal_function 63 __libdwfl_module_free (Dwfl_Module *mod) 64 { 65 if (mod->lazy_cu_root != NULL) 66 tdestroy (mod->lazy_cu_root, nofree); 67 68 if (mod->aranges != NULL) 69 free (mod->aranges); 70 71 if (mod->cu != NULL) 72 { 73 for (size_t i = 0; i < mod->ncu; ++i) 74 free_cu (mod->cu[i]); 75 free (mod->cu); 76 } 77 78 /* We might have primed the Dwarf_CFI ebl cache with our own ebl 79 in __libdwfl_set_cfi. Make sure we don't free it twice. */ 80 if (mod->eh_cfi != NULL) 81 { 82 if (mod->eh_cfi->ebl != NULL && mod->eh_cfi->ebl == mod->ebl) 83 mod->eh_cfi->ebl = NULL; 84 dwarf_cfi_end (mod->eh_cfi); 85 } 86 87 if (mod->dwarf_cfi != NULL) 88 { 89 if (mod->dwarf_cfi->ebl != NULL && mod->dwarf_cfi->ebl == mod->ebl) 90 mod->dwarf_cfi->ebl = NULL; 91 /* We don't need to explicitly destroy the dwarf_cfi. 92 That will be done by dwarf_end. */ 93 } 94 95 if (mod->dw != NULL) 96 { 97 INTUSE(dwarf_end) (mod->dw); 98 if (mod->alt != NULL) 99 { 100 INTUSE(dwarf_end) (mod->alt); 101 if (mod->alt_elf != NULL) 102 elf_end (mod->alt_elf); 103 if (mod->alt_fd != -1) 104 close (mod->alt_fd); 105 } 106 } 107 108 if (mod->ebl != NULL) 109 ebl_closebackend (mod->ebl); 110 111 if (mod->debug.elf != mod->main.elf) 112 free_file (&mod->debug); 113 free_file (&mod->main); 114 free_file (&mod->aux_sym); 115 116 if (mod->build_id_bits != NULL) 117 free (mod->build_id_bits); 118 119 if (mod->reloc_info != NULL) 120 free (mod->reloc_info); 121 122 free (mod->name); 123 free (mod->elfdir); 124 free (mod); 125 } 126 127 void 128 dwfl_report_begin_add (Dwfl *dwfl __attribute__ ((unused))) 129 { 130 /* The lookup table will be cleared on demand, there is nothing we need 131 to do here. */ 132 } 133 INTDEF (dwfl_report_begin_add) 134 135 void 136 dwfl_report_begin (Dwfl *dwfl) 137 { 138 /* Clear the segment lookup table. */ 139 dwfl->lookup_elts = 0; 140 141 for (Dwfl_Module *m = dwfl->modulelist; m != NULL; m = m->next) 142 m->gc = true; 143 144 dwfl->offline_next_address = OFFLINE_REDZONE; 145 } 146 INTDEF (dwfl_report_begin) 147 148 static inline Dwfl_Module * 149 use (Dwfl_Module *mod, Dwfl_Module **tailp, Dwfl *dwfl) 150 { 151 mod->next = *tailp; 152 *tailp = mod; 153 154 if (unlikely (dwfl->lookup_module != NULL)) 155 { 156 free (dwfl->lookup_module); 157 dwfl->lookup_module = NULL; 158 } 159 160 return mod; 161 } 162 163 /* Report that a module called NAME spans addresses [START, END). 164 Returns the module handle, either existing or newly allocated, 165 or returns a null pointer for an allocation error. */ 166 Dwfl_Module * 167 dwfl_report_module (Dwfl *dwfl, const char *name, 168 GElf_Addr start, GElf_Addr end) 169 { 170 Dwfl_Module **tailp = &dwfl->modulelist, **prevp = tailp; 171 172 for (Dwfl_Module *m = *prevp; m != NULL; m = *(prevp = &m->next)) 173 { 174 if (m->low_addr == start && m->high_addr == end 175 && !strcmp (m->name, name)) 176 { 177 /* This module is still here. Move it to the place in the list 178 after the last module already reported. */ 179 *prevp = m->next; 180 m->gc = false; 181 return use (m, tailp, dwfl); 182 } 183 184 if (! m->gc) 185 tailp = &m->next; 186 } 187 188 Dwfl_Module *mod = calloc (1, sizeof *mod); 189 if (mod == NULL) 190 goto nomem; 191 192 mod->name = strdup (name); 193 if (mod->name == NULL) 194 { 195 free (mod); 196 nomem: 197 __libdwfl_seterrno (DWFL_E_NOMEM); 198 return NULL; 199 } 200 201 mod->low_addr = start; 202 mod->high_addr = end; 203 mod->dwfl = dwfl; 204 205 return use (mod, tailp, dwfl); 206 } 207 INTDEF (dwfl_report_module) 208 209 210 /* Finish reporting the current set of modules to the library. 211 If REMOVED is not null, it's called for each module that 212 existed before but was not included in the current report. 213 Returns a nonzero return value from the callback. 214 DWFL cannot be used until this function has returned zero. */ 215 int 216 dwfl_report_end (Dwfl *dwfl, 217 int (*removed) (Dwfl_Module *, void *, 218 const char *, Dwarf_Addr, 219 void *arg), 220 void *arg) 221 { 222 Dwfl_Module **tailp = &dwfl->modulelist; 223 while (*tailp != NULL) 224 { 225 Dwfl_Module *m = *tailp; 226 if (m->gc && removed != NULL) 227 { 228 int result = (*removed) (MODCB_ARGS (m), arg); 229 if (result != 0) 230 return result; 231 } 232 if (m->gc) 233 { 234 *tailp = m->next; 235 __libdwfl_module_free (m); 236 } 237 else 238 tailp = &m->next; 239 } 240 241 return 0; 242 } 243 INTDEF (dwfl_report_end) 244
