251 lines
6.3 KiB
C
251 lines
6.3 KiB
C
/* Minimal replacements for basic facilities used in the dynamic linker.
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Copyright (C) 1995,96,97,98,2000,2001 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, write to the Free
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Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
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02111-1307 USA. */
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#include <errno.h>
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#include <limits.h>
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#include <string.h>
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#include <unistd.h>
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#include <sys/types.h>
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#include <sys/mman.h>
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#include <ldsodefs.h>
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#include <machine/weakalias.h>
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#include <assert.h>
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/* Minimal `malloc' allocator for use while loading shared libraries.
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No block is ever freed. */
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static void *alloc_ptr, *alloc_end, *alloc_last_block;
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/* Declarations of global functions. */
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extern void weak_function free (void *ptr);
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extern void * weak_function realloc (void *ptr, size_t n);
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extern unsigned long int weak_function __strtoul_internal
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(const char *nptr, char **endptr, int base, int group);
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extern unsigned long int weak_function strtoul (const char *nptr,
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char **endptr, int base);
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void * weak_function
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malloc (size_t n)
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{
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#ifdef MAP_ANON
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#define _dl_zerofd (-1)
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#else
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extern int _dl_zerofd;
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if (_dl_zerofd == -1)
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_dl_zerofd = _dl_sysdep_open_zero_fill ();
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#define MAP_ANON 0
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#endif
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if (alloc_end == 0)
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{
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/* Consume any unused space in the last page of our data segment. */
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extern int _end;
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alloc_ptr = &_end;
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alloc_end = (void *) 0 + (((alloc_ptr - (void *) 0) + _dl_pagesize - 1)
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& ~(_dl_pagesize - 1));
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}
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/* Make sure the allocation pointer is ideally aligned. */
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alloc_ptr = (void *) 0 + (((alloc_ptr - (void *) 0) + sizeof (double) - 1)
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& ~(sizeof (double) - 1));
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if (alloc_ptr + n >= alloc_end)
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{
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/* Insufficient space left; allocate another page. */
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caddr_t page;
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size_t nup = (n + _dl_pagesize - 1) & ~(_dl_pagesize - 1);
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page = __mmap (0, nup, PROT_READ|PROT_WRITE,
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MAP_ANON|MAP_PRIVATE, _dl_zerofd, 0);
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assert (page != MAP_FAILED);
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if (page != alloc_end)
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alloc_ptr = page;
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alloc_end = page + nup;
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}
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alloc_last_block = (void *) alloc_ptr;
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alloc_ptr += n;
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return alloc_last_block;
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}
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/* We use this function occasionally since the real implementation may
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be optimized when it can assume the memory it returns already is
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set to NUL. */
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void * weak_function
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calloc (size_t nmemb, size_t size)
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{
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size_t total = nmemb * size;
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void *result = malloc (total);
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return memset (result, '\0', total);
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}
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/* This will rarely be called. */
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void weak_function
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free (void *ptr)
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{
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/* We can free only the last block allocated. */
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if (ptr == alloc_last_block)
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alloc_ptr = alloc_last_block;
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}
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/* This is only called with the most recent block returned by malloc. */
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void * weak_function
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realloc (void *ptr, size_t n)
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{
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void *new;
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if (ptr == NULL)
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return malloc (n);
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assert (ptr == alloc_last_block);
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alloc_ptr = alloc_last_block;
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new = malloc (n);
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assert (new == ptr);
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return new;
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}
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/* Define our own version of the internal function used by strerror. We
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only provide the messages for some common errors. This avoids pulling
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in the whole error list. */
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char * weak_function
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__strerror_r (int errnum, char *buf, size_t buflen)
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{
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char *msg;
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switch (errnum)
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{
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case ENOMEM:
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msg = (char *) "Cannot allocate memory";
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break;
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case EINVAL:
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msg = (char *) "Invalid argument";
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break;
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case ENOENT:
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msg = (char *) "No such file or directory";
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break;
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case EPERM:
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msg = (char *) "Operation not permitted";
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break;
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case EIO:
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msg = (char *) "Input/output error";
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break;
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case EACCES:
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msg = (char *) "Permission denied";
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break;
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default:
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/* No need to check buffer size, all calls in the dynamic linker
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provide enough space. */
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msg = (char *) "Error";
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break;
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}
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return msg;
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}
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#ifndef NDEBUG
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/* Define (weakly) our own assert failure function which doesn't use stdio.
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If we are linked into the user program (-ldl), the normal __assert_fail
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defn can override this one. */
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void weak_function
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__assert_fail (const char *assertion,
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const char *file, unsigned int line, const char *function)
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{
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_dl_fatal_printf ("\
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Inconsistency detected by ld.so: %s: %u: %s%sAssertion `%s' failed!\n",
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file, line, function ?: "", function ? ": " : "",
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assertion);
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}
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void weak_function
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__assert_perror_fail (int errnum,
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const char *file, unsigned int line,
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const char *function)
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{
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char errbuf[64];
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_dl_fatal_printf ("\
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Inconsistency detected by ld.so: %s: %u: %s%sUnexpected error: %s\n",
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file, line, function ?: "", function ? ": " : "",
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__strerror_r (errnum, errbuf, sizeof (errbuf)));
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}
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#endif
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unsigned long int weak_function
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__strtoul_internal (const char *nptr, char **endptr, int base, int group)
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{
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unsigned long int result = 0;
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long int sign = 1;
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while (*nptr == ' ' || *nptr == '\t')
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++nptr;
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if (*nptr == '-')
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{
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sign = -1;
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++nptr;
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}
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else if (*nptr == '+')
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++nptr;
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if (*nptr < '0' || *nptr > '9')
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{
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if (endptr != NULL)
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*endptr = (char *) nptr;
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return 0UL;
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}
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assert (base == 0);
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base = 10;
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if (*nptr == '0')
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{
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if (nptr[1] == 'x' || nptr[1] == 'X')
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{
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base = 16;
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nptr += 2;
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}
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else
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base = 8;
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}
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while (*nptr >= '0' && *nptr <= '9')
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{
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unsigned long int digval = *nptr - '0';
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if (result > LONG_MAX / 10
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|| (result == ULONG_MAX / 10 && digval > ULONG_MAX % 10))
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{
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errno = ERANGE;
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if (endptr != NULL)
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*endptr = (char *) nptr;
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return ULONG_MAX;
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}
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result *= base;
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result += digval;
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++nptr;
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}
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if (endptr != NULL)
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*endptr = (char *) nptr;
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return result * sign;
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}
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