1 /* Minimal replacements for basic facilities used in the dynamic linker.
2 Copyright (C) 1995 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
17 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
18 Cambridge, MA 02139, USA. */
20 #include <sys/types.h>
26 #include "../stdio-common/_itoa.h"
28 /* Minimal `malloc' allocator for use while loading shared libraries.
29 Only small blocks are allocated, and none are ever freed. */
31 static void *alloc_ptr
, *alloc_end
, *alloc_last_block
;
36 extern int _dl_zerofd
;
37 static size_t pagesize
;
40 pagesize
= __getpagesize ();
43 _dl_zerofd
= _dl_sysdep_open_zero_fill ();
47 /* Consume any unused space in the last page of our data segment. */
50 alloc_end
= (void *) 0 + (((alloc_ptr
- (void *) 0) + pagesize
- 1)
54 /* Make sure the allocation pointer is ideally aligned. */
55 alloc_ptr
= (void *) 0 + (((alloc_ptr
- (void *) 0) + sizeof (double) - 1)
56 & ~(sizeof (double) - 1));
58 if (alloc_ptr
+ n
>= alloc_end
)
60 /* Insufficient space left; allocate another page. */
62 assert (n
<= pagesize
);
63 page
= mmap (0, pagesize
, PROT_READ
|PROT_WRITE
,
64 MAP_ANON
|MAP_PRIVATE
, _dl_zerofd
, 0);
65 assert (page
!= (caddr_t
) -1);
66 if (page
!= alloc_end
)
68 alloc_end
= page
+ pagesize
;
71 alloc_last_block
= (void *) alloc_ptr
;
73 return alloc_last_block
;
77 /* This will rarely be called. */
81 /* We can free only the last block allocated. */
82 if (ptr
== alloc_last_block
)
83 alloc_ptr
= alloc_last_block
;
87 /* This is never called. */
89 realloc (void *ptr
, size_t n
)
90 { ptr
+= n
; abort (); }
93 /* Avoid signal frobnication in setjmp/longjmp. Keeps things smaller. */
97 int __sigjmp_save (sigjmp_buf env
, int savemask
)
98 { env
[0].__mask_was_saved
= savemask
; return 0; }
99 weak_symbol (__sigjmp_save
)
102 longjmp (jmp_buf env
, int val
) { __longjmp (env
[0].__jmpbuf
, val
); }
103 weak_symbol (longjmp
)
106 /* Define our own stub for the localization function used by strerror.
107 English-only in the dynamic linker keeps it smaller. */
110 __dgettext (const char *domainname
, const char *msgid
)
112 assert (domainname
== _libc_intl_domainname
);
113 return (char *) msgid
;
115 weak_symbol (__dgettext
)
116 weak_alias (__dgettext
, dgettext
)
120 /* Define (weakly) our own assert failure function which doesn't use stdio.
121 If we are linked into the user program (-ldl), the normal __assert_fail
122 defn can override this one. */
125 __assert_fail (const char *assertion
,
126 const char *file
, unsigned int line
, const char *function
)
129 buf
[sizeof buf
- 1] = '\0';
130 _dl_sysdep_fatal ("BUG IN DYNAMIC LINKER ld.so: ",
131 file
, ": ", _itoa (line
, buf
+ sizeof buf
- 1, 10, 0),
132 ": ", function
?: "", function
? ": " : "",
133 "Assertion `", assertion
, "' failed!\n",
137 weak_symbol (__assert_fail
)
140 __assert_perror_fail (int errnum
,
141 const char *file
, unsigned int line
,
142 const char *function
)
145 buf
[sizeof buf
- 1] = '\0';
146 _dl_sysdep_fatal ("BUG IN DYNAMIC LINKER ld.so: ",
147 file
, ": ", _itoa (line
, buf
+ sizeof buf
- 1, 10, 0),
148 ": ", function
?: "", function
? ": " : "",
149 "Unexpected error: ", strerror (errnum
), "\n", NULL
);
152 weak_symbol (__assert_perror_fail
)