1 /* Close a shared object opened by `_dl_open'.
2 Copyright (C) 1996, 1997, 1998, 1999 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Library General Public License as
7 published by the Free Software Foundation; either version 2 of the
8 License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Library General Public License for more details.
15 You should have received a copy of the GNU Library General Public
16 License along with the GNU C Library; see the file COPYING.LIB. If not,
17 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA. */
24 #include <bits/libc-lock.h>
25 #include <elf/ldsodefs.h>
26 #include <sys/types.h>
30 /* During the program run we must not modify the global data of
31 loaded shared object simultanously in two threads. Therefore we
32 protect `dlopen' and `dlclose' in dlclose.c. */
33 __libc_lock_define (extern, _dl_load_lock
)
35 #define LOSE(s) _dl_signal_error (0, map->l_name, s)
39 _dl_close (void *_map
)
41 struct link_map
**list
;
42 struct link_map
*map
= _map
;
46 if (map
->l_opencount
== 0)
47 LOSE ("shared object not open");
49 /* Acquire the lock. */
50 __libc_lock_lock (_dl_load_lock
);
52 /* Decrement the reference count. */
53 if (map
->l_opencount
> 1 || map
->l_type
!= lt_loaded
)
55 /* There are still references to this object. Do nothing more. */
57 __libc_lock_unlock (_dl_load_lock
);
61 list
= map
->l_searchlist
.r_list
;
62 nsearchlist
= map
->l_searchlist
.r_nlist
;
64 /* Call all termination functions at once. */
65 for (i
= 0; i
< nsearchlist
; ++i
)
67 struct link_map
*imap
= list
[i
];
68 if (imap
->l_opencount
== 1 && imap
->l_type
== lt_loaded
69 && imap
->l_info
[DT_FINI
]
70 /* Skip any half-cooked objects that were never initialized. */
71 && imap
->l_init_called
)
73 /* When debugging print a message first. */
74 if (_dl_debug_impcalls
)
75 _dl_debug_message (1, "\ncalling fini: ", imap
->l_name
,
77 /* Call its termination function. */
78 (*(void (*) (void)) ((void *) imap
->l_addr
79 + imap
->l_info
[DT_FINI
]->d_un
.d_ptr
)) ();
83 /* Notify the debugger we are about to remove some loaded objects. */
84 _r_debug
.r_state
= RT_DELETE
;
87 /* The search list contains a counted reference to each object it
88 points to, the 0th elt being MAP itself. Decrement the reference
89 counts on all the objects MAP depends on. */
90 for (i
= 0; i
< nsearchlist
; ++i
)
91 --list
[i
]->l_opencount
;
93 /* Check each element of the search list to see if all references to
95 for (i
= 0; i
< nsearchlist
; ++i
)
97 struct link_map
*imap
= list
[i
];
98 if (imap
->l_opencount
== 0 && imap
->l_type
== lt_loaded
)
100 struct libname_list
*lnp
;
102 /* That was the last reference, and this was a dlopen-loaded
103 object. We can unmap it. */
106 /* This object is in the global scope list. Remove it. */
107 int cnt
= _dl_main_searchlist
->r_nlist
;
111 while (_dl_main_searchlist
->r_list
[cnt
] != imap
);
113 /* The object was already correctly registered. */
114 while (++cnt
< _dl_main_searchlist
->r_nlist
)
115 _dl_main_searchlist
->r_list
[cnt
- 1]
116 = _dl_main_searchlist
->r_list
[cnt
];
118 --_dl_main_searchlist
->r_nlist
;
121 /* We can unmap all the maps at once. We determined the
122 start address and length when we loaded the object and
123 the `munmap' call does the rest. */
124 __munmap ((void *) imap
->l_map_start
,
125 imap
->l_map_end
- imap
->l_map_start
);
127 /* Finally, unlink the data structure and free it. */
129 /* We will unlink the first object only if this is a statically
131 assert (imap
->l_prev
!= NULL
);
132 imap
->l_prev
->l_next
= imap
->l_next
;
134 if (imap
->l_prev
!= NULL
)
135 imap
->l_prev
->l_next
= imap
->l_next
;
137 _dl_loaded
= imap
->l_next
;
140 imap
->l_next
->l_prev
= imap
->l_prev
;
142 if (imap
->l_versions
!= NULL
)
143 free (imap
->l_versions
);
144 if (imap
->l_origin
!= NULL
&& imap
->l_origin
!= (char *) -1)
145 free ((char *) imap
->l_origin
);
147 /* This name always is allocated. */
149 /* Remove the list with all the names of the shared object. */
150 lnp
= imap
->l_libname
;
153 struct libname_list
*this = lnp
;
159 /* Remove the searchlists. */
160 if (imap
->l_searchlist
.r_duplist
!= imap
->l_searchlist
.r_list
)
162 /* If a r_list exists there always also is a r_duplist. */
163 assert (imap
->l_searchlist
.r_list
!= NULL
);
164 free (imap
->l_searchlist
.r_duplist
);
166 if (imap
!= map
&& imap
->l_searchlist
.r_list
!= NULL
)
167 free (imap
->l_searchlist
.r_list
);
169 if (imap
->l_phdr_allocated
)
170 free ((void *) imap
->l_phdr
);
178 if (_dl_global_scope_alloc
!= 0
179 && _dl_main_searchlist
->r_nlist
== _dl_initial_searchlist
.r_nlist
)
181 /* All object dynamically loaded by the program are unloaded. Free
182 the memory allocated for the global scope variable. */
183 struct link_map
**old
= _dl_main_searchlist
->r_list
;
185 /* Put the old map in. */
186 _dl_main_searchlist
->r_list
= _dl_initial_searchlist
.r_list
;
187 /* Signal that the original map is used. */
188 _dl_global_scope_alloc
= 0;
190 /* Now free the old map. */
194 /* Notify the debugger those objects are finalized and gone. */
195 _r_debug
.r_state
= RT_CONSISTENT
;
198 /* Release the lock. */
199 __libc_lock_unlock (_dl_load_lock
);