1 /* Maintenance of module list in libdwfl.
2 Copyright (C) 2005, 2006, 2007, 2008, 2014 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 <search.h>
31 #include <unistd.h>
32
33 static void
free_cu(struct dwfl_cu * cu)34 free_cu (struct dwfl_cu *cu)
35 {
36 if (cu->lines != NULL)
37 free (cu->lines);
38 free (cu);
39 }
40
41 static void
nofree(void * arg)42 nofree (void *arg __attribute__ ((unused)))
43 {
44 }
45
46 static void
free_file(struct dwfl_file * file)47 free_file (struct dwfl_file *file)
48 {
49 free (file->name);
50
51 /* Close the fd only on the last reference. */
52 if (file->elf != NULL && elf_end (file->elf) == 0 && file->fd != -1)
53 close (file->fd);
54 }
55
56 void
57 internal_function
__libdwfl_module_free(Dwfl_Module * mod)58 __libdwfl_module_free (Dwfl_Module *mod)
59 {
60 if (mod->lazy_cu_root != NULL)
61 tdestroy (mod->lazy_cu_root, nofree);
62
63 if (mod->aranges != NULL)
64 free (mod->aranges);
65
66 if (mod->cu != NULL)
67 {
68 for (size_t i = 0; i < mod->ncu; ++i)
69 free_cu (mod->cu[i]);
70 free (mod->cu);
71 }
72
73 if (mod->dw != NULL)
74 {
75 INTUSE(dwarf_end) (mod->dw);
76 if (mod->alt != NULL)
77 {
78 INTUSE(dwarf_end) (mod->alt);
79 if (mod->alt_elf != NULL)
80 elf_end (mod->alt_elf);
81 if (mod->alt_fd != -1)
82 close (mod->alt_fd);
83 }
84 }
85
86 if (mod->ebl != NULL)
87 ebl_closebackend (mod->ebl);
88
89 if (mod->debug.elf != mod->main.elf)
90 free_file (&mod->debug);
91 free_file (&mod->main);
92 free_file (&mod->aux_sym);
93
94 if (mod->build_id_bits != NULL)
95 free (mod->build_id_bits);
96
97 if (mod->reloc_info != NULL)
98 free (mod->reloc_info);
99
100 if (mod->eh_cfi != NULL)
101 dwarf_cfi_end (mod->eh_cfi);
102
103 free (mod->name);
104 free (mod);
105 }
106
107 void
dwfl_report_begin_add(Dwfl * dwfl)108 dwfl_report_begin_add (Dwfl *dwfl __attribute__ ((unused)))
109 {
110 /* The lookup table will be cleared on demand, there is nothing we need
111 to do here. */
112 }
INTDEF(dwfl_report_begin_add)113 INTDEF (dwfl_report_begin_add)
114
115 void
116 dwfl_report_begin (Dwfl *dwfl)
117 {
118 /* Clear the segment lookup table. */
119 dwfl->lookup_elts = 0;
120
121 for (Dwfl_Module *m = dwfl->modulelist; m != NULL; m = m->next)
122 m->gc = true;
123
124 dwfl->offline_next_address = OFFLINE_REDZONE;
125 }
INTDEF(dwfl_report_begin)126 INTDEF (dwfl_report_begin)
127
128 /* Report that a module called NAME spans addresses [START, END).
129 Returns the module handle, either existing or newly allocated,
130 or returns a null pointer for an allocation error. */
131 Dwfl_Module *
132 dwfl_report_module (Dwfl *dwfl, const char *name,
133 GElf_Addr start, GElf_Addr end)
134 {
135 Dwfl_Module **tailp = &dwfl->modulelist, **prevp = tailp;
136
137 inline Dwfl_Module *use (Dwfl_Module *mod)
138 {
139 mod->next = *tailp;
140 *tailp = mod;
141
142 if (unlikely (dwfl->lookup_module != NULL))
143 {
144 free (dwfl->lookup_module);
145 dwfl->lookup_module = NULL;
146 }
147
148 return mod;
149 }
150
151 for (Dwfl_Module *m = *prevp; m != NULL; m = *(prevp = &m->next))
152 {
153 if (m->low_addr == start && m->high_addr == end
154 && !strcmp (m->name, name))
155 {
156 /* This module is still here. Move it to the place in the list
157 after the last module already reported. */
158 *prevp = m->next;
159 m->gc = false;
160 return use (m);
161 }
162
163 if (! m->gc)
164 tailp = &m->next;
165 }
166
167 Dwfl_Module *mod = calloc (1, sizeof *mod);
168 if (mod == NULL)
169 goto nomem;
170
171 mod->name = strdup (name);
172 if (mod->name == NULL)
173 {
174 free (mod);
175 nomem:
176 __libdwfl_seterrno (DWFL_E_NOMEM);
177 return NULL;
178 }
179
180 mod->low_addr = start;
181 mod->high_addr = end;
182 mod->dwfl = dwfl;
183
184 return use (mod);
185 }
INTDEF(dwfl_report_module)186 INTDEF (dwfl_report_module)
187
188
189 /* Finish reporting the current set of modules to the library.
190 If REMOVED is not null, it's called for each module that
191 existed before but was not included in the current report.
192 Returns a nonzero return value from the callback.
193 DWFL cannot be used until this function has returned zero. */
194 int
195 dwfl_report_end (Dwfl *dwfl,
196 int (*removed) (Dwfl_Module *, void *,
197 const char *, Dwarf_Addr,
198 void *arg),
199 void *arg)
200 {
201 Dwfl_Module **tailp = &dwfl->modulelist;
202 while (*tailp != NULL)
203 {
204 Dwfl_Module *m = *tailp;
205 if (m->gc && removed != NULL)
206 {
207 int result = (*removed) (MODCB_ARGS (m), arg);
208 if (result != 0)
209 return result;
210 }
211 if (m->gc)
212 {
213 *tailp = m->next;
214 __libdwfl_module_free (m);
215 }
216 else
217 tailp = &m->next;
218 }
219
220 return 0;
221 }
222 INTDEF (dwfl_report_end)
223