1/* Maintenance of module list in libdwfl.
2   Copyright (C) 2005, 2006, 2007, 2008 Red Hat, Inc.
3   This file is part of Red Hat elfutils.
4
5   Red Hat elfutils is free software; you can redistribute it and/or modify
6   it under the terms of the GNU General Public License as published by the
7   Free Software Foundation; version 2 of the License.
8
9   Red Hat elfutils is distributed in the hope that it will be useful, but
10   WITHOUT ANY WARRANTY; without even the implied warranty of
11   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12   General Public License for more details.
13
14   You should have received a copy of the GNU General Public License along
15   with Red Hat elfutils; if not, write to the Free Software Foundation,
16   Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA.
17
18   In addition, as a special exception, Red Hat, Inc. gives You the
19   additional right to link the code of Red Hat elfutils with code licensed
20   under any Open Source Initiative certified open source license
21   (http://www.opensource.org/licenses/index.php) which requires the
22   distribution of source code with any binary distribution and to
23   distribute linked combinations of the two.  Non-GPL Code permitted under
24   this exception must only link to the code of Red Hat elfutils through
25   those well defined interfaces identified in the file named EXCEPTION
26   found in the source code files (the "Approved Interfaces").  The files
27   of Non-GPL Code may instantiate templates or use macros or inline
28   functions from the Approved Interfaces without causing the resulting
29   work to be covered by the GNU General Public License.  Only Red Hat,
30   Inc. may make changes or additions to the list of Approved Interfaces.
31   Red Hat's grant of this exception is conditioned upon your not adding
32   any new exceptions.  If you wish to add a new Approved Interface or
33   exception, please contact Red Hat.  You must obey the GNU General Public
34   License in all respects for all of the Red Hat elfutils code and other
35   code used in conjunction with Red Hat elfutils except the Non-GPL Code
36   covered by this exception.  If you modify this file, you may extend this
37   exception to your version of the file, but you are not obligated to do
38   so.  If you do not wish to provide this exception without modification,
39   you must delete this exception statement from your version and license
40   this file solely under the GPL without exception.
41
42   Red Hat elfutils is an included package of the Open Invention Network.
43   An included package of the Open Invention Network is a package for which
44   Open Invention Network licensees cross-license their patents.  No patent
45   license is granted, either expressly or impliedly, by designation as an
46   included package.  Should you wish to participate in the Open Invention
47   Network licensing program, please visit www.openinventionnetwork.com
48   <http://www.openinventionnetwork.com>.  */
49
50#include "libdwflP.h"
51#include <search.h>
52#include <unistd.h>
53
54static void
55free_cu (struct dwfl_cu *cu)
56{
57  if (cu->lines != NULL)
58    free (cu->lines);
59  free (cu);
60}
61
62static void
63nofree (void *arg __attribute__ ((unused)))
64{
65}
66
67static void
68free_file (struct dwfl_file *file)
69{
70  free (file->name);
71
72  /* Close the fd only on the last reference.  */
73  if (file->elf != NULL && elf_end (file->elf) == 0 && file->fd != -1)
74    close (file->fd);
75}
76
77void
78internal_function
79__libdwfl_module_free (Dwfl_Module *mod)
80{
81  if (mod->lazy_cu_root != NULL)
82    tdestroy (mod->lazy_cu_root, nofree);
83
84  if (mod->aranges != NULL)
85    free (mod->aranges);
86
87  if (mod->cu != NULL)
88    {
89      for (size_t i = 0; i < mod->ncu; ++i)
90	free_cu (mod->cu[i]);
91      free (mod->cu);
92    }
93
94  if (mod->dw != NULL)
95    INTUSE(dwarf_end) (mod->dw);
96
97  if (mod->ebl != NULL)
98    ebl_closebackend (mod->ebl);
99
100  if (mod->debug.elf != mod->main.elf)
101    free_file (&mod->debug);
102  free_file (&mod->main);
103
104  if (mod->build_id_bits != NULL)
105    free (mod->build_id_bits);
106
107  free (mod->name);
108  free (mod);
109}
110
111void
112dwfl_report_begin_add (Dwfl *dwfl __attribute__ ((unused)))
113{
114  /* The lookup table will be cleared on demand, there is nothing we need
115     to do here.  */
116}
117INTDEF (dwfl_report_begin_add)
118
119void
120dwfl_report_begin (Dwfl *dwfl)
121{
122  /* Clear the segment lookup table.  */
123  dwfl->lookup_elts = 0;
124
125  for (Dwfl_Module *m = dwfl->modulelist; m != NULL; m = m->next)
126    m->gc = true;
127
128  dwfl->offline_next_address = OFFLINE_REDZONE;
129}
130INTDEF (dwfl_report_begin)
131
132/* Report that a module called NAME spans addresses [START, END).
133   Returns the module handle, either existing or newly allocated,
134   or returns a null pointer for an allocation error.  */
135Dwfl_Module *
136dwfl_report_module (Dwfl *dwfl, const char *name,
137		    GElf_Addr start, GElf_Addr end)
138{
139  Dwfl_Module **tailp = &dwfl->modulelist, **prevp = tailp;
140
141  inline Dwfl_Module *use (Dwfl_Module *mod)
142  {
143    mod->next = *tailp;
144    *tailp = mod;
145
146    if (unlikely (dwfl->lookup_module != NULL))
147      {
148	free (dwfl->lookup_module);
149	dwfl->lookup_module = NULL;
150      }
151
152    return mod;
153  }
154
155  for (Dwfl_Module *m = *prevp; m != NULL; m = *(prevp = &m->next))
156    {
157      if (m->low_addr == start && m->high_addr == end
158	  && !strcmp (m->name, name))
159	{
160	  /* This module is still here.  Move it to the place in the list
161	     after the last module already reported.  */
162	  *prevp = m->next;
163	  m->gc = false;
164	  return use (m);
165	}
166
167      if (! m->gc)
168	tailp = &m->next;
169    }
170
171  Dwfl_Module *mod = calloc (1, sizeof *mod);
172  if (mod == NULL)
173    goto nomem;
174
175  mod->name = strdup (name);
176  if (mod->name == NULL)
177    {
178      free (mod);
179    nomem:
180      __libdwfl_seterrno (DWFL_E_NOMEM);
181      return NULL;
182    }
183
184  mod->low_addr = start;
185  mod->high_addr = end;
186  mod->dwfl = dwfl;
187
188  return use (mod);
189}
190INTDEF (dwfl_report_module)
191
192
193/* Finish reporting the current set of modules to the library.
194   If REMOVED is not null, it's called for each module that
195   existed before but was not included in the current report.
196   Returns a nonzero return value from the callback.
197   DWFL cannot be used until this function has returned zero.  */
198int
199dwfl_report_end (Dwfl *dwfl,
200		 int (*removed) (Dwfl_Module *, void *,
201				 const char *, Dwarf_Addr,
202				 void *arg),
203		 void *arg)
204{
205  Dwfl_Module **tailp = &dwfl->modulelist;
206  while (*tailp != NULL)
207    {
208      Dwfl_Module *m = *tailp;
209      if (m->gc && removed != NULL)
210	{
211	  int result = (*removed) (MODCB_ARGS (m), arg);
212	  if (result != 0)
213	    return result;
214	}
215      if (m->gc)
216	{
217	  *tailp = m->next;
218	  __libdwfl_module_free (m);
219	}
220      else
221	tailp = &m->next;
222    }
223
224  return 0;
225}
226INTDEF (dwfl_report_end)
227