1 /* Handle symbol and library versioning.
2 Copyright (C) 1997 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Library General Public License as
8 published by the Free Software Foundation; either version 2 of the
9 License, or (at your option) any later version.
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Library General Public License for more details.
16 You should have received a copy of the GNU Library General Public
17 License along with the GNU C Library; see the file COPYING.LIB. If not,
18 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
28 #include "../stdio-common/_itoa.h"
31 /* Set in rtld.c at startup. */
32 extern char **_dl_argv
;
34 #define VERSTAG(tag) (DT_NUM + DT_PROCNUM + DT_VERSIONTAGIDX (tag))
37 #define make_string(string, rest...) \
39 const char *all[] = { string, ## rest }; \
44 for (cnt = 0; cnt < sizeof (all) / sizeof (all[0]); ++cnt) \
45 len += strlen (all[cnt]); \
47 cp = result = alloca (len); \
48 for (cnt = 0; cnt < sizeof (all) / sizeof (all[0]); ++cnt) \
49 cp = stpcpy (cp, all[cnt]); \
55 static inline struct link_map
*
56 find_needed (struct link_map
*map
, const char *name
)
60 for (n
= 0; n
< map
->l_nsearchlist
; ++n
)
61 if (_dl_name_match_p (name
, map
->l_searchlist
[n
]))
62 return map
->l_searchlist
[n
];
64 /* Should never happen. */
70 match_symbol (const char *name
, ElfW(Word
) hash
, const char *string
,
71 struct link_map
*map
, int verbose
, int weak
)
73 const char *strtab
= (const char *) (map
->l_addr
74 + map
->l_info
[DT_STRTAB
]->d_un
.d_ptr
);
75 ElfW(Addr
) def_offset
= map
->l_info
[VERSTAG (DT_VERDEF
)]->d_un
.d_ptr
;
80 /* The file has no symbol versioning. I.e., the dependent
81 object was linked against another version of this file. We
82 only print a message if verbose output is requested. */
84 _dl_signal_error (0, map
->l_name
, make_string ("\
85 no version information available (required by ",
90 def
= (ElfW(Verdef
) *) (map
->l_addr
+ def_offset
);
93 /* Currently the version number of the definition entry is 1.
94 Make sure all we see is this version. */
95 if (def
->vd_version
!= 1)
98 buf
[sizeof (buf
) - 1] = '\0';
99 _dl_signal_error (0, map
->l_name
,
100 make_string ("unsupported version ",
101 _itoa_word (def
->vd_version
,
102 &buf
[sizeof (buf
) - 1],
104 " of Verdef record"));
108 /* Compare the hash values. */
109 if (hash
== def
->vd_hash
)
111 ElfW(Verdaux
) *aux
= (ElfW(Verdaux
) *) ((char *) def
+ def
->vd_aux
);
113 /* To be safe, compare the string as well. */
114 if (strcmp (string
, strtab
+ aux
->vda_name
) == 0)
119 /* If no more definitions we failed to find what we want. */
120 if (def
->vd_next
== 0)
123 /* Next definition. */
124 def
= (ElfW(Verdef
) *) ((char *) def
+ def
->vd_next
);
127 /* Symbol not found. If it was a weak reference it is not fatal. */
131 _dl_signal_error (0, map
->l_name
,
132 make_string ("weak version `", string
,
133 "' not found (required by ", name
,
138 _dl_signal_error (0, map
->l_name
,
139 make_string ("version `", string
,
140 "' not found (required by ", name
, ")"));
146 _dl_check_map_versions (struct link_map
*map
, int verbose
)
149 const char *strtab
= (const char *) (map
->l_addr
150 + map
->l_info
[DT_STRTAB
]->d_un
.d_ptr
);
151 /* Pointer to section with needed versions. */
152 ElfW(Dyn
) *dyn
= map
->l_info
[VERSTAG (DT_VERNEED
)];
153 /* Pointer to dynamic section with definitions. */
154 ElfW(Dyn
) *def
= map
->l_info
[VERSTAG (DT_VERDEF
)];
155 /* We need to find out which is the highest version index used
157 unsigned int ndx_high
= 0;
161 /* This file requires special versions from its dependencies. */
162 ElfW(Verneed
) *ent
= (ElfW(Verneed
) *) (map
->l_addr
+ dyn
->d_un
.d_ptr
);
164 /* Currently the version number of the needed entry is 1.
165 Make sure all we see is this version. */
166 if (ent
->vn_version
!= 1)
169 buf
[sizeof (buf
) - 1] = '\0';
170 _dl_signal_error (0, (*map
->l_name
? map
->l_name
: _dl_argv
[0]),
171 make_string ("unsupported version ",
172 _itoa_word (ent
->vn_version
,
173 &buf
[sizeof (buf
) - 1],
175 " of Verneed record\n"));
182 struct link_map
*needed
= find_needed (map
, strtab
+ ent
->vn_file
);
184 /* If NEEDED is NULL this means a dependency was not found
185 and no stub entry was created. This should never happen. */
186 assert (needed
!= NULL
);
188 /* NEEDED is the map for the file we need. Now look for the
189 dependency symbols. */
190 aux
= (ElfW(Vernaux
) *) ((char *) ent
+ ent
->vn_aux
);
193 /* Match the symbol. */
194 result
|= match_symbol ((*map
->l_name
195 ? map
->l_name
: _dl_argv
[0]),
197 strtab
+ aux
->vna_name
,
199 aux
->vna_flags
& VER_FLG_WEAK
);
201 /* Compare the version index. */
202 if ((unsigned int) (aux
->vna_other
& 0x7fff) > ndx_high
)
203 ndx_high
= aux
->vna_other
& 0x7fff;
205 if (aux
->vna_next
== 0)
206 /* No more symbols. */
210 aux
= (ElfW(Vernaux
) *) ((char *) aux
+ aux
->vna_next
);
213 if (ent
->vn_next
== 0)
214 /* No more dependencies. */
217 /* Next dependency. */
218 ent
= (ElfW(Verneed
) *) ((char *) ent
+ ent
->vn_next
);
222 /* We also must store the names of the defined versions. Determine
223 the maximum index here as well.
225 XXX We could avoid the loop by just taking the number of definitions
226 as an upper bound of new indeces. */
230 ent
= (ElfW(Verdef
) *) (map
->l_addr
+ def
->d_un
.d_ptr
);
233 if ((unsigned int) (ent
->vd_ndx
& 0x7fff) > ndx_high
)
234 ndx_high
= ent
->vd_ndx
& 0x7fff;
236 if (ent
->vd_next
== 0)
237 /* No more definitions. */
240 ent
= (ElfW(Verdef
) *) ((char *) ent
+ ent
->vd_next
);
246 /* Now we are ready to build the array with the version names
247 which can be indexed by the version index in the VERSYM
249 map
->l_versions
= (struct r_found_version
*)
250 calloc (ndx_high
+ 1, sizeof (*map
->l_versions
));
251 if (map
->l_versions
== NULL
)
253 _dl_signal_error (ENOMEM
, (*map
->l_name
? map
->l_name
: _dl_argv
[0]),
254 "cannot allocate version reference table");
259 /* Store the number of available symbols. */
260 map
->l_nversions
= ndx_high
+ 1;
265 ent
= (ElfW(Verneed
) *) (map
->l_addr
+ dyn
->d_un
.d_ptr
);
269 aux
= (ElfW(Vernaux
) *) ((char *) ent
+ ent
->vn_aux
);
272 ElfW(Half
) ndx
= aux
->vna_other
& 0x7fff;
273 map
->l_versions
[ndx
].hash
= aux
->vna_hash
;
274 map
->l_versions
[ndx
].name
= &strtab
[aux
->vna_name
];
275 map
->l_versions
[ndx
].filename
= &strtab
[ent
->vn_file
];
277 if (aux
->vna_next
== 0)
278 /* No more symbols. */
281 /* Advance to next symbol. */
282 aux
= (ElfW(Vernaux
) *) ((char *) aux
+ aux
->vna_next
);
285 if (ent
->vn_next
== 0)
286 /* No more dependencies. */
289 /* Advance to next dependency. */
290 ent
= (ElfW(Verneed
) *) ((char *) ent
+ ent
->vn_next
);
294 /* And insert the defined versions. */
298 ent
= (ElfW(Verdef
) *) (map
->l_addr
+ def
->d_un
.d_ptr
);
302 aux
= (ElfW(Verdaux
) *) ((char *) ent
+ ent
->vd_aux
);
304 if ((ent
->vd_flags
& VER_FLG_BASE
) == 0)
306 /* The name of the base version should not be
307 available for matching a versioned symbol. */
308 ElfW(Half
) ndx
= ent
->vd_ndx
& 0x7fff;
309 map
->l_versions
[ndx
].hash
= ent
->vd_hash
;
310 map
->l_versions
[ndx
].name
= &strtab
[aux
->vda_name
];
311 map
->l_versions
[ndx
].filename
= NULL
;
314 if (ent
->vd_next
== 0)
315 /* No more definitions. */
318 ent
= (ElfW(Verdef
) *) ((char *) ent
+ ent
->vd_next
);
329 _dl_check_all_versions (struct link_map
*map
, int verbose
)
334 for (l
= map
; l
!= NULL
; l
= l
->l_next
)
335 result
|= l
->l_opencount
!= 0 && _dl_check_map_versions (l
, verbose
);