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+/* Minimal replacements for basic facilities used in the dynamic linker.
+Copyright (C) 1995 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB. If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA. */
+
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <unistd.h>
+#include <assert.h>
+#include <string.h>
+#include <link.h>
+#include "../stdio-common/_itoa.h"
+
+/* Minimal `malloc' allocator for use while loading shared libraries.
+ Only small blocks are allocated, and none are ever freed. */
+
+static void *alloc_ptr, *alloc_end, *alloc_last_block;
+
+void *
+malloc (size_t n)
+{
+ extern int _dl_zerofd;
+ static size_t pagesize;
+
+ if (pagesize == 0)
+ pagesize = __getpagesize ();
+
+ if (_dl_zerofd == -1)
+ _dl_zerofd = _dl_sysdep_open_zero_fill ();
+
+ if (alloc_end == 0)
+ {
+ /* Consume any unused space in the last page of our data segment. */
+ extern int _end;
+ alloc_ptr = &_end;
+ alloc_end = (void *) 0 + (((alloc_ptr - (void *) 0) + pagesize - 1)
+ & ~(pagesize - 1));
+ }
+
+ /* Make sure the allocation pointer is ideally aligned. */
+ alloc_ptr = (void *) 0 + (((alloc_ptr - (void *) 0) + sizeof (double) - 1)
+ & ~(sizeof (double) - 1));
+
+ if (alloc_ptr + n >= alloc_end)
+ {
+ /* Insufficient space left; allocate another page. */
+ caddr_t page;
+ assert (n <= pagesize);
+ page = mmap (0, pagesize, PROT_READ|PROT_WRITE, MAP_ANON, _dl_zerofd, 0);
+ assert (page != (caddr_t) -1);
+ if (page != alloc_end)
+ alloc_ptr = page;
+ alloc_end = page + pagesize;
+ }
+
+ alloc_last_block = (void *) alloc_ptr;
+ alloc_ptr += n;
+ return alloc_last_block;
+}
+weak_symbol (malloc)
+
+/* This will rarely be called. */
+void
+free (void *ptr)
+{
+ /* We can free only the last block allocated. */
+ if (ptr == alloc_last_block)
+ alloc_ptr = alloc_last_block;
+}
+weak_symbol (free)
+
+/* This is never called. */
+void *
+realloc (void *ptr, size_t n)
+{ ptr += n; abort (); }
+weak_symbol (realloc)
+
+/* Avoid signal frobnication in setjmp/longjmp. Keeps things smaller. */
+
+#include <setjmp.h>
+
+int __sigjmp_save (sigjmp_buf env, int savemask)
+{ env[0].__mask_was_saved = savemask; return 0; }
+weak_symbol (__sigjmp_save)
+
+void
+longjmp (jmp_buf env, int val) { __longjmp (env[0].__jmpbuf, val); }
+weak_symbol (longjmp)
+
+
+/* Define our own stub for the localization function used by strerror.
+ English-only in the dynamic linker keeps it smaller. */
+
+char *
+__dgettext (const char *domainname, const char *msgid)
+{
+ assert (domainname == _libc_intl_domainname);
+ return (char *) msgid;
+}
+weak_symbol (__dgettext)
+weak_alias (__dgettext, dgettext)
+
+#ifndef NDEBUG
+
+/* Define (weakly) our own assert failure function which doesn't use stdio.
+ If we are linked into the user program (-ldl), the normal __assert_fail
+ defn can override this one. */
+
+void
+__assert_fail (const char *assertion,
+ const char *file, unsigned int line, const char *function)
+{
+ char buf[64];
+ buf[sizeof buf - 1] = '\0';
+ _dl_sysdep_fatal ("BUG IN DYNAMIC LINKER ld.so: ",
+ file, ": ", _itoa (line, buf + sizeof buf - 1, 10, 0),
+ ": ", function ?: "", function ? ": " : "",
+ "Assertion `", assertion, "' failed!\n",
+ NULL);
+
+}
+weak_symbol (__assert_fail)
+
+void
+__assert_perror_fail (int errnum,
+ const char *file, unsigned int line,
+ const char *function)
+{
+ char buf[64];
+ buf[sizeof buf - 1] = '\0';
+ _dl_sysdep_fatal ("BUG IN DYNAMIC LINKER ld.so: ",
+ file, ": ", _itoa (line, buf + sizeof buf - 1, 10, 0),
+ ": ", function ?: "", function ? ": " : "",
+ "Unexpected error: ", strerror (errnum), "\n", NULL);
+
+}
+weak_symbol (__assert_perror_fail)
+
+#endif