1 /* Minimal replacements for basic facilities used in the dynamic linker.
2 Copyright (C) 1995, 1996 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;
38 if (_dl_pagesize == 0)
39 _dl_pagesize = __getpagesize ();
42 _dl_zerofd = _dl_sysdep_open_zero_fill ();
46 /* Consume any unused space in the last page of our data segment. */
49 alloc_end = (void *) 0 + (((alloc_ptr - (void *) 0) + _dl_pagesize - 1)
50 & ~(_dl_pagesize - 1));
53 /* Make sure the allocation pointer is ideally aligned. */
54 alloc_ptr = (void *) 0 + (((alloc_ptr - (void *) 0) + sizeof (double) - 1)
55 & ~(sizeof (double) - 1));
57 if (alloc_ptr + n >= alloc_end)
59 /* Insufficient space left; allocate another page. */
61 assert (n <= _dl_pagesize);
62 page = __mmap (0, _dl_pagesize, PROT_READ|PROT_WRITE,
63 MAP_ANON|MAP_PRIVATE, _dl_zerofd, 0);
64 assert (page != (caddr_t) -1);
65 if (page != alloc_end)
67 alloc_end = page + _dl_pagesize;
70 alloc_last_block = (void *) alloc_ptr;
72 return alloc_last_block;
75 /* This will rarely be called. */
79 /* We can free only the last block allocated. */
80 if (ptr == alloc_last_block)
81 alloc_ptr = alloc_last_block;
84 /* This is only called with the most recent block returned by malloc. */
86 realloc (void *ptr, size_t n)
89 assert (ptr == alloc_last_block);
90 alloc_ptr = alloc_last_block;
96 /* Avoid signal frobnication in setjmp/longjmp. Keeps things smaller. */
101 __sigjmp_save (sigjmp_buf env, int savemask)
102 { env[0].__mask_was_saved = savemask; return 0; }
105 longjmp (jmp_buf env, int val) { __longjmp (env[0].__jmpbuf, val); }
107 /* Define our own stub for the localization function used by strerror.
108 English-only in the dynamic linker keeps it smaller. */
111 __dgettext (const char *domainname, const char *msgid)
113 assert (domainname == _libc_intl_domainname);
114 return (char *) msgid;
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",
139 __assert_perror_fail (int errnum,
140 const char *file, unsigned int line,
141 const char *function)
144 buf[sizeof buf - 1] = '\0';
145 _dl_sysdep_fatal ("BUG IN DYNAMIC LINKER ld.so: ",
146 file, ": ", _itoa (line, buf + sizeof buf - 1, 10, 0),
147 ": ", function ?: "", function ? ": " : "",
148 "Unexpected error: ", strerror (errnum), "\n", NULL);