1 /* Get public symbol information.
2 Copyright (C) 2002, 2003, 2004, 2005, 2008 Red Hat, Inc.
3 This file is part of elfutils.
4 Written by Ulrich Drepper <drepper@redhat.com>, 2002.
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 <assert.h>
35 #include <stdlib.h>
36 #include <string.h>
37
38 #include <libdwP.h>
39 #include <dwarf.h>
40 #include <system.h>
41
42
43 static int
get_offsets(Dwarf * dbg)44 get_offsets (Dwarf *dbg)
45 {
46 size_t allocated = 0;
47 size_t cnt = 0;
48 struct pubnames_s *mem = NULL;
49 const size_t entsize = sizeof (struct pubnames_s);
50 unsigned char *const startp = dbg->sectiondata[IDX_debug_pubnames]->d_buf;
51 unsigned char *readp = startp;
52 unsigned char *endp = readp + dbg->sectiondata[IDX_debug_pubnames]->d_size;
53
54 while (readp + 14 < endp)
55 {
56 /* If necessary, allocate more entries. */
57 if (cnt >= allocated)
58 {
59 allocated = MAX (10, 2 * allocated);
60 struct pubnames_s *newmem = realloc (mem, allocated * entsize);
61 if (newmem == NULL)
62 {
63 __libdw_seterrno (DWARF_E_NOMEM);
64 err_return:
65 free (mem);
66 return -1;
67 }
68
69 mem = newmem;
70 }
71
72 /* Read the set header. */
73 int len_bytes = 4;
74 Dwarf_Off len = read_4ubyte_unaligned_inc (dbg, readp);
75 if (len == DWARF3_LENGTH_64_BIT)
76 {
77 len = read_8ubyte_unaligned_inc (dbg, readp);
78 len_bytes = 8;
79 }
80 else if (unlikely (len >= DWARF3_LENGTH_MIN_ESCAPE_CODE
81 && len <= DWARF3_LENGTH_MAX_ESCAPE_CODE))
82 {
83 __libdw_seterrno (DWARF_E_INVALID_DWARF);
84 goto err_return;
85 }
86
87 /* Now we know the offset of the first offset/name pair. */
88 mem[cnt].set_start = readp + 2 + 2 * len_bytes - startp;
89 mem[cnt].address_len = len_bytes;
90 size_t max_size = dbg->sectiondata[IDX_debug_pubnames]->d_size;
91 if (mem[cnt].set_start >= max_size
92 || len - (2 + 2 * len_bytes) > max_size - mem[cnt].set_start)
93 /* Something wrong, the first entry is beyond the end of
94 the section. Or the length of the whole unit is too big. */
95 break;
96
97 /* Read the version. It better be two for now. */
98 uint16_t version = read_2ubyte_unaligned (dbg, readp);
99 if (unlikely (version != 2))
100 {
101 __libdw_seterrno (DWARF_E_INVALID_VERSION);
102 goto err_return;
103 }
104
105 /* Get the CU offset. */
106 if (__libdw_read_offset (dbg, dbg, IDX_debug_pubnames,
107 readp + 2, len_bytes,
108 &mem[cnt].cu_offset, IDX_debug_info, 3))
109 /* Error has been already set in reader. */
110 goto err_return;
111
112 /* Determine the size of the CU header. */
113 unsigned char *infop
114 = ((unsigned char *) dbg->sectiondata[IDX_debug_info]->d_buf
115 + mem[cnt].cu_offset);
116 if (read_4ubyte_unaligned_noncvt (infop) == DWARF3_LENGTH_64_BIT)
117 mem[cnt].cu_header_size = 23;
118 else
119 mem[cnt].cu_header_size = 11;
120
121 ++cnt;
122
123 /* Advance to the next set. */
124 readp += len;
125 }
126
127 if (mem == NULL || cnt == 0)
128 {
129 free (mem);
130 __libdw_seterrno (DWARF_E_NO_ENTRY);
131 return -1;
132 }
133
134 dbg->pubnames_sets = realloc (mem, cnt * entsize);
135 dbg->pubnames_nsets = cnt;
136
137 return 0;
138 }
139
140
141 ptrdiff_t
dwarf_getpubnames(Dwarf * dbg,int (* callback)(Dwarf *,Dwarf_Global *,void *),void * arg,ptrdiff_t offset)142 dwarf_getpubnames (Dwarf *dbg,
143 int (*callback) (Dwarf *, Dwarf_Global *, void *),
144 void *arg, ptrdiff_t offset)
145 {
146 if (dbg == NULL)
147 return -1l;
148
149 if (unlikely (offset < 0))
150 {
151 __libdw_seterrno (DWARF_E_INVALID_OFFSET);
152 return -1l;
153 }
154
155 /* Make sure it is a valid offset. */
156 if (unlikely (dbg->sectiondata[IDX_debug_pubnames] == NULL
157 || ((size_t) offset
158 >= dbg->sectiondata[IDX_debug_pubnames]->d_size)))
159 /* No (more) entry. */
160 return 0;
161
162 /* If necessary read the set information. */
163 if (dbg->pubnames_nsets == 0 && unlikely (get_offsets (dbg) != 0))
164 return -1l;
165
166 /* Find the place where to start. */
167 size_t cnt;
168 if (offset == 0)
169 {
170 cnt = 0;
171 offset = dbg->pubnames_sets[0].set_start;
172 }
173 else
174 {
175 for (cnt = 0; cnt + 1 < dbg->pubnames_nsets; ++cnt)
176 if ((Dwarf_Off) offset >= dbg->pubnames_sets[cnt].set_start)
177 {
178 assert ((Dwarf_Off) offset
179 < dbg->pubnames_sets[cnt + 1].set_start);
180 break;
181 }
182 assert (cnt + 1 < dbg->pubnames_nsets);
183 }
184
185 unsigned char *startp
186 = (unsigned char *) dbg->sectiondata[IDX_debug_pubnames]->d_buf;
187 unsigned char *endp
188 = startp + dbg->sectiondata[IDX_debug_pubnames]->d_size;
189 unsigned char *readp = startp + offset;
190 while (1)
191 {
192 Dwarf_Global gl;
193
194 gl.cu_offset = (dbg->pubnames_sets[cnt].cu_offset
195 + dbg->pubnames_sets[cnt].cu_header_size);
196
197 while (1)
198 {
199 /* READP points to the next offset/name pair. */
200 if (readp + dbg->pubnames_sets[cnt].address_len > endp)
201 goto invalid_dwarf;
202 if (dbg->pubnames_sets[cnt].address_len == 4)
203 gl.die_offset = read_4ubyte_unaligned_inc (dbg, readp);
204 else
205 gl.die_offset = read_8ubyte_unaligned_inc (dbg, readp);
206
207 /* If the offset is zero we reached the end of the set. */
208 if (gl.die_offset == 0)
209 break;
210
211 /* Add the CU offset. */
212 gl.die_offset += dbg->pubnames_sets[cnt].cu_offset;
213
214 gl.name = (char *) readp;
215 readp = (unsigned char *) memchr (gl.name, '\0', endp - readp);
216 if (unlikely (readp == NULL))
217 {
218 invalid_dwarf:
219 __libdw_seterrno (DWARF_E_INVALID_DWARF);
220 return -1l;
221 }
222 readp++;
223
224 /* We found name and DIE offset. Report it. */
225 if (callback (dbg, &gl, arg) != DWARF_CB_OK)
226 {
227 /* The user wants us to stop. Return the offset of the
228 next entry. */
229 return readp - startp;
230 }
231 }
232
233 if (++cnt == dbg->pubnames_nsets)
234 /* This was the last set. */
235 break;
236
237 startp = (unsigned char *) dbg->sectiondata[IDX_debug_pubnames]->d_buf;
238 readp = startp + dbg->pubnames_sets[cnt].set_start;
239 }
240
241 /* We are done. No more entries. */
242 return 0;
243 }
244