1/* Get public symbol information.
2   Copyright (C) 2002, 2003, 2004, 2005, 2008 Red Hat, Inc.
3   This file is part of Red Hat elfutils.
4   Written by Ulrich Drepper <drepper@redhat.com>, 2002.
5
6   Red Hat elfutils is free software; you can redistribute it and/or modify
7   it under the terms of the GNU General Public License as published by the
8   Free Software Foundation; version 2 of the License.
9
10   Red Hat elfutils is distributed in the hope that it will be useful, but
11   WITHOUT ANY WARRANTY; without even the implied warranty of
12   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13   General Public License for more details.
14
15   You should have received a copy of the GNU General Public License along
16   with Red Hat elfutils; if not, write to the Free Software Foundation,
17   Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA.
18
19   In addition, as a special exception, Red Hat, Inc. gives You the
20   additional right to link the code of Red Hat elfutils with code licensed
21   under any Open Source Initiative certified open source license
22   (http://www.opensource.org/licenses/index.php) which requires the
23   distribution of source code with any binary distribution and to
24   distribute linked combinations of the two.  Non-GPL Code permitted under
25   this exception must only link to the code of Red Hat elfutils through
26   those well defined interfaces identified in the file named EXCEPTION
27   found in the source code files (the "Approved Interfaces").  The files
28   of Non-GPL Code may instantiate templates or use macros or inline
29   functions from the Approved Interfaces without causing the resulting
30   work to be covered by the GNU General Public License.  Only Red Hat,
31   Inc. may make changes or additions to the list of Approved Interfaces.
32   Red Hat's grant of this exception is conditioned upon your not adding
33   any new exceptions.  If you wish to add a new Approved Interface or
34   exception, please contact Red Hat.  You must obey the GNU General Public
35   License in all respects for all of the Red Hat elfutils code and other
36   code used in conjunction with Red Hat elfutils except the Non-GPL Code
37   covered by this exception.  If you modify this file, you may extend this
38   exception to your version of the file, but you are not obligated to do
39   so.  If you do not wish to provide this exception without modification,
40   you must delete this exception statement from your version and license
41   this file solely under the GPL without exception.
42
43   Red Hat elfutils is an included package of the Open Invention Network.
44   An included package of the Open Invention Network is a package for which
45   Open Invention Network licensees cross-license their patents.  No patent
46   license is granted, either expressly or impliedly, by designation as an
47   included package.  Should you wish to participate in the Open Invention
48   Network licensing program, please visit www.openinventionnetwork.com
49   <http://www.openinventionnetwork.com>.  */
50
51#ifdef HAVE_CONFIG_H
52# include <config.h>
53#endif
54
55#include <assert.h>
56#include <stdlib.h>
57#include <string.h>
58#include <sys/param.h>
59
60#include <libdwP.h>
61#include <dwarf.h>
62
63/* ANDROID_CHANGE_BEGIN */
64#include <AndroidFixup.h>
65/* ANDROID_CHANGE_END */
66
67static int
68get_offsets (Dwarf *dbg)
69{
70  size_t allocated = 0;
71  size_t cnt = 0;
72  struct pubnames_s *mem = NULL;
73  const size_t entsize = sizeof (struct pubnames_s);
74  unsigned char *const startp = dbg->sectiondata[IDX_debug_pubnames]->d_buf;
75  unsigned char *readp = startp;
76  unsigned char *endp = readp + dbg->sectiondata[IDX_debug_pubnames]->d_size;
77
78  while (readp + 14 < endp)
79    {
80      /* If necessary, allocate more entries.  */
81      if (cnt >= allocated)
82	{
83	  allocated = MAX (10, 2 * allocated);
84	  struct pubnames_s *newmem
85	    = (struct pubnames_s *) realloc (mem, allocated * entsize);
86	  if (newmem == NULL)
87	    {
88	      __libdw_seterrno (DWARF_E_NOMEM);
89	    err_return:
90	      free (mem);
91	      return -1;
92	    }
93
94	  mem = newmem;
95	}
96
97      /* Read the set header.  */
98      int len_bytes = 4;
99      Dwarf_Off len = read_4ubyte_unaligned_inc (dbg, readp);
100      if (len == DWARF3_LENGTH_64_BIT)
101	{
102	  len = read_8ubyte_unaligned_inc (dbg, readp);
103	  len_bytes = 8;
104	}
105      else if (unlikely (len >= DWARF3_LENGTH_MIN_ESCAPE_CODE
106			 && len <= DWARF3_LENGTH_MAX_ESCAPE_CODE))
107	{
108	invalid_dwarf:
109	  __libdw_seterrno (DWARF_E_INVALID_DWARF);
110	  goto err_return;
111	}
112
113      /* Now we know the offset of the first offset/name pair.  */
114      mem[cnt].set_start = readp + 2 + 2 * len_bytes - startp;
115      mem[cnt].address_len = len_bytes;
116      if (mem[cnt].set_start >= dbg->sectiondata[IDX_debug_pubnames]->d_size)
117	/* Something wrong, the first entry is beyond the end of
118	   the section.  */
119	break;
120
121      /* Read the version.  It better be two for now.  */
122      uint16_t version = read_2ubyte_unaligned (dbg, readp);
123      if (unlikely (version != 2))
124	{
125	  __libdw_seterrno (DWARF_E_INVALID_VERSION);
126	  goto err_return;
127	}
128
129      /* Get the CU offset.  */
130      if (len_bytes == 4)
131	mem[cnt].cu_offset = read_4ubyte_unaligned (dbg, readp + 2);
132      else
133	mem[cnt].cu_offset = read_8ubyte_unaligned (dbg, readp + 2);
134
135      /* Determine the size of the CU header.  */
136      if (unlikely (dbg->sectiondata[IDX_debug_info] == NULL
137		    || dbg->sectiondata[IDX_debug_info]->d_buf == NULL
138		    || (mem[cnt].cu_offset + 3
139			>= dbg->sectiondata[IDX_debug_info]->d_size)))
140	goto invalid_dwarf;
141
142      unsigned char *infop
143	= ((unsigned char *) dbg->sectiondata[IDX_debug_info]->d_buf
144	   + mem[cnt].cu_offset);
145      if (read_4ubyte_unaligned_noncvt (infop) == DWARF3_LENGTH_64_BIT)
146	mem[cnt].cu_header_size = 23;
147      else
148	mem[cnt].cu_header_size = 11;
149
150      ++cnt;
151
152      /* Advance to the next set.  */
153      readp += len;
154    }
155
156  if (mem == NULL)
157    {
158      __libdw_seterrno (DWARF_E_NO_ENTRY);
159      return -1;
160    }
161
162  dbg->pubnames_sets = (struct pubnames_s *) realloc (mem, cnt * entsize);
163  dbg->pubnames_nsets = cnt;
164
165  return 0;
166}
167
168
169ptrdiff_t
170dwarf_getpubnames (dbg, callback, arg, offset)
171     Dwarf *dbg;
172     int (*callback) (Dwarf *, Dwarf_Global *, void *);
173     void *arg;
174     ptrdiff_t offset;
175{
176  if (dbg == NULL)
177    return -1l;
178
179  if (unlikely (offset < 0))
180    {
181      __libdw_seterrno (DWARF_E_INVALID_OFFSET);
182      return -1l;
183    }
184
185  /* Make sure it is a valid offset.  */
186  if (unlikely (dbg->sectiondata[IDX_debug_pubnames] == NULL
187		|| ((size_t) offset
188		    >= dbg->sectiondata[IDX_debug_pubnames]->d_size)))
189    /* No (more) entry.  */
190    return 0;
191
192  /* If necessary read the set information.  */
193  if (dbg->pubnames_nsets == 0 && unlikely (get_offsets (dbg) != 0))
194    return -1l;
195
196  /* Find the place where to start.  */
197  size_t cnt;
198  if (offset == 0)
199    {
200      cnt = 0;
201      offset = dbg->pubnames_sets[0].set_start;
202    }
203  else
204    {
205      for (cnt = 0; cnt + 1 < dbg->pubnames_nsets; ++cnt)
206	if ((Dwarf_Off) offset >= dbg->pubnames_sets[cnt].set_start)
207	  {
208	    assert ((Dwarf_Off) offset
209		    < dbg->pubnames_sets[cnt + 1].set_start);
210	    break;
211	  }
212      assert (cnt + 1 < dbg->pubnames_nsets);
213    }
214
215  unsigned char *startp
216    = (unsigned char *) dbg->sectiondata[IDX_debug_pubnames]->d_buf;
217  unsigned char *readp = startp + offset;
218  while (1)
219    {
220      Dwarf_Global gl;
221
222      gl.cu_offset = (dbg->pubnames_sets[cnt].cu_offset
223		      + dbg->pubnames_sets[cnt].cu_header_size);
224
225      while (1)
226	{
227	  /* READP points to the next offset/name pair.  */
228	  if (dbg->pubnames_sets[cnt].address_len == 4)
229	    gl.die_offset = read_4ubyte_unaligned_inc (dbg, readp);
230	  else
231	    gl.die_offset = read_8ubyte_unaligned_inc (dbg, readp);
232
233	  /* If the offset is zero we reached the end of the set.  */
234	  if (gl.die_offset == 0)
235	    break;
236
237	  /* Add the CU offset.  */
238	  gl.die_offset += dbg->pubnames_sets[cnt].cu_offset;
239
240	  gl.name = (char *) readp;
241	  readp = (unsigned char *) rawmemchr (gl.name, '\0') + 1;
242
243	  /* We found name and DIE offset.  Report it.  */
244	  if (callback (dbg, &gl, arg) != DWARF_CB_OK)
245	    {
246	      /* The user wants us to stop.  Return the offset of the
247		 next entry.  */
248	      return readp - startp;
249	    }
250	}
251
252      if (++cnt == dbg->pubnames_nsets)
253	/* This was the last set.  */
254	break;
255
256      startp = (unsigned char *) dbg->sectiondata[IDX_debug_pubnames]->d_buf;
257      readp = startp + dbg->pubnames_sets[cnt].set_start;
258    }
259
260  /* We are done.  No more entries.  */
261  return 0;
262}
263