/* Minimal replacements for basic facilities used in the dynamic linker.
- Copyright (C) 1995,96,97,98,2000 Free Software Foundation, Inc.
+ Copyright (C) 1995-2019 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.
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 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.
+ Lesser 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., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
#include <errno.h>
#include <limits.h>
+#include <stdio.h>
#include <string.h>
+#include <tls.h>
#include <unistd.h>
-#include <sys/types.h>
#include <sys/mman.h>
+#include <sys/param.h>
+#include <sys/types.h>
#include <ldsodefs.h>
-#include <stdio-common/_itoa.h>
+#include <_itoa.h>
+#include <malloc/malloc-internal.h>
#include <assert.h>
-/* Minimal `malloc' allocator for use while loading shared libraries.
- No block is ever freed. */
+/* Minimal malloc allocator for used during initial link. After the
+ initial link, a full malloc implementation is interposed, either
+ the one in libc, or a different one supplied by the user through
+ interposition. */
static void *alloc_ptr, *alloc_end, *alloc_last_block;
/* Declarations of global functions. */
extern void weak_function free (void *ptr);
extern void * weak_function realloc (void *ptr, size_t n);
-extern long int weak_function __strtol_internal (const char *nptr,
- char **endptr,
- int base, int group);
-extern long int weak_function strtol (const char *nptr, char **endptr,
- int base);
-extern unsigned long int weak_function __strtoul_internal
-(const char *nptr, char **endptr, int base, int group);
-extern unsigned long int weak_function strtoul (const char *nptr,
- char **endptr, int base);
+/* Allocate an aligned memory block. */
void * weak_function
malloc (size_t n)
{
-#ifdef MAP_ANON
-#define _dl_zerofd (-1)
-#else
- extern int _dl_zerofd;
-
- if (_dl_zerofd == -1)
- _dl_zerofd = _dl_sysdep_open_zero_fill ();
-#define MAP_ANON 0
-#endif
-
if (alloc_end == 0)
{
/* Consume any unused space in the last page of our data segment. */
- extern int _end;
+ extern int _end attribute_hidden;
alloc_ptr = &_end;
- alloc_end = (void *) 0 + (((alloc_ptr - (void *) 0) + _dl_pagesize - 1)
- & ~(_dl_pagesize - 1));
+ alloc_end = (void *) 0 + (((alloc_ptr - (void *) 0)
+ + GLRO(dl_pagesize) - 1)
+ & ~(GLRO(dl_pagesize) - 1));
}
/* Make sure the allocation pointer is ideally aligned. */
- alloc_ptr = (void *) 0 + (((alloc_ptr - (void *) 0) + sizeof (double) - 1)
- & ~(sizeof (double) - 1));
+ alloc_ptr = (void *) 0 + (((alloc_ptr - (void *) 0) + MALLOC_ALIGNMENT - 1)
+ & ~(MALLOC_ALIGNMENT - 1));
- if (alloc_ptr + n >= alloc_end)
+ if (alloc_ptr + n >= alloc_end || n >= -(uintptr_t) alloc_ptr)
{
- /* Insufficient space left; allocate another page. */
+ /* Insufficient space left; allocate another page plus one extra
+ page to reduce number of mmap calls. */
caddr_t page;
- size_t nup = (n + _dl_pagesize - 1) & ~(_dl_pagesize - 1);
+ size_t nup = (n + GLRO(dl_pagesize) - 1) & ~(GLRO(dl_pagesize) - 1);
+ if (__glibc_unlikely (nup == 0 && n != 0))
+ return NULL;
+ nup += GLRO(dl_pagesize);
page = __mmap (0, nup, PROT_READ|PROT_WRITE,
- MAP_ANON|MAP_PRIVATE, _dl_zerofd, 0);
- assert (page != MAP_FAILED);
+ MAP_ANON|MAP_PRIVATE, -1, 0);
+ if (page == MAP_FAILED)
+ return NULL;
if (page != alloc_end)
alloc_ptr = page;
alloc_end = page + nup;
void * weak_function
calloc (size_t nmemb, size_t size)
{
- size_t total = nmemb * size;
- void *result = malloc (total);
- return memset (result, '\0', total);
+ /* New memory from the trivial malloc above is always already cleared.
+ (We make sure that's true in the rare occasion it might not be,
+ by clearing memory in free, below.) */
+ size_t bytes = nmemb * size;
+
+#define HALF_SIZE_T (((size_t) 1) << (8 * sizeof (size_t) / 2))
+ if (__builtin_expect ((nmemb | size) >= HALF_SIZE_T, 0)
+ && size != 0 && bytes / size != nmemb)
+ return NULL;
+
+ return malloc (bytes);
}
/* This will rarely be called. */
{
/* We can free only the last block allocated. */
if (ptr == alloc_last_block)
- alloc_ptr = alloc_last_block;
+ {
+ /* Since this is rare, we clear the freed block here
+ so that calloc can presume malloc returns cleared memory. */
+ memset (alloc_last_block, '\0', alloc_ptr - alloc_last_block);
+ alloc_ptr = alloc_last_block;
+ }
}
/* This is only called with the most recent block returned by malloc. */
void * weak_function
realloc (void *ptr, size_t n)
{
- void *new;
+ if (ptr == NULL)
+ return malloc (n);
assert (ptr == alloc_last_block);
+ size_t old_size = alloc_ptr - alloc_last_block;
alloc_ptr = alloc_last_block;
- new = malloc (n);
- assert (new == ptr);
- return new;
+ void *new = malloc (n);
+ return new != ptr ? memcpy (new, ptr, old_size) : new;
}
\f
/* Avoid signal frobnication in setjmp/longjmp. Keeps things smaller. */
#include <setjmp.h>
int weak_function
-__sigjmp_save (sigjmp_buf env, int savemask)
+__sigjmp_save (sigjmp_buf env, int savemask __attribute__ ((unused)))
{
- env[0].__mask_was_saved = savemask;
+ env[0].__mask_was_saved = 0;
return 0;
}
-
-void weak_function
-longjmp (jmp_buf env, int val)
-{
- __longjmp (env[0].__jmpbuf, val);
-}
\f
/* Define our own version of the internal function used by strerror. We
only provide the messages for some common errors. This avoids pulling
/* No need to check buffer size, all calls in the dynamic linker
provide enough space. */
buf[buflen - 1] = '\0';
- msg = _itoa_word (errnum, buf + buflen - 1, 10, 0);
+ msg = _itoa (errnum, buf + buflen - 1, 10, 0);
msg = memcpy (msg - (sizeof ("Error ") - 1), "Error ",
sizeof ("Error ") - 1);
break;
return msg;
}
\f
-#ifndef NDEBUG
+void
+__libc_fatal (const char *message)
+{
+ _dl_fatal_printf ("%s", message);
+}
+rtld_hidden_def (__libc_fatal)
+void
+__attribute__ ((noreturn))
+__chk_fail (void)
+{
+ _exit (127);
+}
+rtld_hidden_def (__chk_fail)
+
+#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. */
__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_word (line, buf + sizeof buf - 1, 10, 0),
- ": ", function ?: "", function ? ": " : "",
- "Assertion `", assertion, "' failed!\n",
- NULL);
+ _dl_fatal_printf ("\
+Inconsistency detected by ld.so: %s: %u: %s%sAssertion `%s' failed!\n",
+ file, line, function ?: "", function ? ": " : "",
+ assertion);
}
+rtld_hidden_weak (__assert_fail)
void weak_function
__assert_perror_fail (int errnum,
const char *file, unsigned int line,
const char *function)
{
- char errbuf[64];
- char buf[64];
- buf[sizeof buf - 1] = '\0';
- _dl_sysdep_fatal ("BUG IN DYNAMIC LINKER ld.so: ",
- file, ": ", _itoa_word (line, buf + sizeof buf - 1, 10, 0),
- ": ", function ?: "", function ? ": " : "",
- "Unexpected error: ",
- __strerror_r (errnum, errbuf, sizeof (errbuf)), "\n",
- NULL);
+ char errbuf[400];
+ _dl_fatal_printf ("\
+Inconsistency detected by ld.so: %s: %u: %s%sUnexpected error: %s.\n",
+ file, line, function ?: "", function ? ": " : "",
+ __strerror_r (errnum, errbuf, sizeof errbuf));
}
-
+rtld_hidden_weak (__assert_perror_fail)
#endif
-
-/* This function is only used in eval.c. */
-long int weak_function
-__strtol_internal (const char *nptr, char **endptr, int base, int group)
+\f
+#undef _itoa
+/* We always use _itoa instead of _itoa_word in ld.so since the former
+ also has to be present and it is never about speed when these
+ functions are used. */
+char *
+_itoa (unsigned long long int value, char *buflim, unsigned int base,
+ int upper_case)
{
- unsigned long int result = 0;
- long int sign = 1;
+ assert (! upper_case);
- while (*nptr == ' ' || *nptr == '\t')
- ++nptr;
+ do
+ *--buflim = _itoa_lower_digits[value % base];
+ while ((value /= base) != 0);
- if (*nptr == '-')
- {
- sign = -1;
- ++nptr;
- }
- else if (*nptr == '+')
- ++nptr;
-
- if (*nptr < '0' || *nptr > '9')
- {
- if (endptr != NULL)
- *endptr = (char *) nptr;
- return 0L;
- }
-
- assert (base == 0);
- base = 10;
- if (*nptr == '0')
- {
- if (nptr[1] == 'x' || nptr[1] == 'X')
- {
- base = 16;
- nptr += 2;
- }
- else
- base = 8;
- }
-
- while (*nptr >= '0' && *nptr <= '9')
- {
- unsigned long int digval = *nptr - '0';
- if (result > LONG_MAX / 10
- || (sign > 0 ? result == LONG_MAX / 10 && digval > LONG_MAX % 10
- : (result == ((unsigned long int) LONG_MAX + 1) / 10
- && digval > ((unsigned long int) LONG_MAX + 1) % 10)))
- {
- errno = ERANGE;
- return sign > 0 ? LONG_MAX : LONG_MIN;
- }
- result *= base;
- result += digval;
- ++nptr;
- }
-
- return (long int) result * sign;
+ return buflim;
}
-long int weak_function
-strtol (const char *nptr, char **endptr, int base)
-{
- return __strtol_internal (nptr, endptr, base, 0);
-}
-
-unsigned long int weak_function
-__strtoul_internal (const char *nptr, char **endptr, int base, int group)
+/* The '_itoa_lower_digits' variable in libc.so is able to handle bases
+ up to 36. We don't need this here. */
+const char _itoa_lower_digits[16] = "0123456789abcdef";
+rtld_hidden_data_def (_itoa_lower_digits)
+\f
+/* The following is not a complete strsep implementation. It cannot
+ handle empty delimiter strings. But this isn't necessary for the
+ execution of ld.so. */
+#undef strsep
+#undef __strsep
+char *
+__strsep (char **stringp, const char *delim)
{
- unsigned long int result = 0;
- long int sign = 1;
-
- while (*nptr == ' ' || *nptr == '\t')
- ++nptr;
+ char *begin;
- if (*nptr == '-')
- {
- sign = -1;
- ++nptr;
- }
- else if (*nptr == '+')
- ++nptr;
+ assert (delim[0] != '\0');
- if (*nptr < '0' || *nptr > '9')
+ begin = *stringp;
+ if (begin != NULL)
{
- if (endptr != NULL)
- *endptr = (char *) nptr;
- return 0UL;
- }
+ char *end = begin;
- assert (base == 0);
- base = 10;
- if (*nptr == '0')
- {
- if (nptr[1] == 'x' || nptr[1] == 'X')
+ while (*end != '\0' || (end = NULL))
{
- base = 16;
- nptr += 2;
- }
- else
- base = 8;
- }
+ const char *dp = delim;
- while (*nptr >= '0' && *nptr <= '9')
- {
- unsigned long int digval = *nptr - '0';
- if (result > LONG_MAX / 10
- || (result == ULONG_MAX / 10 && digval > ULONG_MAX % 10))
- {
- errno = ERANGE;
- return ULONG_MAX;
+ do
+ if (*dp == *end)
+ break;
+ while (*++dp != '\0');
+
+ if (*dp != '\0')
+ {
+ *end++ = '\0';
+ break;
+ }
+
+ ++end;
}
- result *= base;
- result += digval;
- ++nptr;
- }
- return result * sign;
-}
+ *stringp = end;
+ }
-unsigned long int weak_function
-strtoul (const char *nptr, char **endptr, int base)
-{
- return (unsigned long int) __strtoul_internal (nptr, endptr, base, 0);
+ return begin;
}
+weak_alias (__strsep, strsep)
+strong_alias (__strsep, __strsep_g)