/* Miscellaneous support functions for dynamic linker
Copyright (C) 1997-2018 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 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
Lesser General Public License for more details.
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 <assert.h>
#include <fcntl.h>
#include <ldsodefs.h>
#include <limits.h>
#include <link.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <stdint.h>
#include <sys/mman.h>
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/uio.h>
#include <sysdep.h>
#include <_itoa.h>
#include <dl-writev.h>
#include <not-cancel.h>
/* Read the whole contents of FILE into new mmap'd space with given
protections. *SIZEP gets the size of the file. On error MAP_FAILED
is returned. */
void *
_dl_sysdep_read_whole_file (const char *file, size_t *sizep, int prot)
{
void *result = MAP_FAILED;
struct stat64 st;
int fd = __open64_nocancel (file, O_RDONLY | O_CLOEXEC);
if (fd >= 0)
{
if (__fxstat64 (_STAT_VER, fd, &st) >= 0)
{
*sizep = st.st_size;
/* No need to map the file if it is empty. */
if (*sizep != 0)
/* Map a copy of the file contents. */
result = __mmap (NULL, *sizep, prot,
#ifdef MAP_COPY
MAP_COPY
#else
MAP_PRIVATE
#endif
#ifdef MAP_FILE
| MAP_FILE
#endif
, fd, 0);
}
__close_nocancel (fd);
}
return result;
}
/* Bare-bones printf implementation. This function only knows about
the formats and flags needed and can handle only up to 64 stripes in
the output. */
static void
_dl_debug_vdprintf (int fd, int tag_p, const char *fmt, va_list arg)
{
# define NIOVMAX 64
struct iovec iov[NIOVMAX];
int niov = 0;
pid_t pid = 0;
char pidbuf[12];
while (*fmt != '\0')
{
const char *startp = fmt;
if (tag_p > 0)
{
/* Generate the tag line once. It consists of the PID and a
colon followed by a tab. */
if (pid == 0)
{
char *p;
pid = __getpid ();
assert (pid >= 0 && sizeof (pid_t) <= 4);
p = _itoa (pid, &pidbuf[10], 10, 0);
while (p > pidbuf)
*--p = ' ';
pidbuf[10] = ':';
pidbuf[11] = '\t';
}
/* Append to the output. */
assert (niov < NIOVMAX);
iov[niov].iov_len = 12;
iov[niov++].iov_base = pidbuf;
/* No more tags until we see the next newline. */
tag_p = -1;
}
/* Skip everything except % and \n (if tags are needed). */
while (*fmt != '\0' && *fmt != '%' && (! tag_p || *fmt != '\n'))
++fmt;
/* Append constant string. */
assert (niov < NIOVMAX);
if ((iov[niov].iov_len = fmt - startp) != 0)
iov[niov++].iov_base = (char *) startp;
if (*fmt == '%')
{
/* It is a format specifier. */
char fill = ' ';
int width = -1;
int prec = -1;
#if LONG_MAX != INT_MAX
int long_mod = 0;
#endif
/* Recognize zero-digit fill flag. */
if (*++fmt == '0')
{
fill = '0';
++fmt;
}
/* See whether with comes from a parameter. Note that no other
way to specify the width is implemented. */
if (*fmt == '*')
{
width = va_arg (arg, int);
++fmt;
}
/* Handle precision. */
if (*fmt == '.' && fmt[1] == '*')
{
prec = va_arg (arg, int);
fmt += 2;
}
/* Recognize the l modifier. It is only important on some
platforms where long and int have a different size. We
can use the same code for size_t. */
if (*fmt == 'l' || *fmt == 'Z')
{
#if LONG_MAX != INT_MAX
long_mod = 1;
#endif
++fmt;
}
switch (*fmt)
{
/* Integer formatting. */
case 'd':
case 'u':
case 'x':
{
/* We have to make a difference if long and int have a
different size. */
#if LONG_MAX != INT_MAX
unsigned long int num = (long_mod
? va_arg (arg, unsigned long int)
: va_arg (arg, unsigned int));
#else
unsigned long int num = va_arg (arg, unsigned int);
#endif
bool negative = false;
if (*fmt == 'd')
{
#if LONG_MAX != INT_MAX
if (long_mod)
{
if ((long int) num < 0)
negative = true;
}
else
{
if ((int) num < 0)
{
num = (unsigned int) num;
negative = true;
}
}
#else
if ((int) num < 0)
negative = true;
#endif
}
/* We use alloca() to allocate the buffer with the most
pessimistic guess for the size. Using alloca() allows
having more than one integer formatting in a call. */
char *buf = (char *) alloca (1 + 3 * sizeof (unsigned long int));
char *endp = &buf[1 + 3 * sizeof (unsigned long int)];
char *cp = _itoa (num, endp, *fmt == 'x' ? 16 : 10, 0);
/* Pad to the width the user specified. */
if (width != -1)
while (endp - cp < width)
*--cp = fill;
if (negative)
*--cp = '-';
iov[niov].iov_base = cp;
iov[niov].iov_len = endp - cp;
++niov;
}
break;
case 's':
/* Get the string argument. */
iov[niov].iov_base = va_arg (arg, char *);
iov[niov].iov_len = strlen (iov[niov].iov_base);
if (prec != -1)
iov[niov].iov_len = MIN ((size_t) prec, iov[niov].iov_len);
++niov;
break;
case '%':
iov[niov].iov_base = (void *) fmt;
iov[niov].iov_len = 1;
++niov;
break;
default:
assert (! "invalid format specifier");
}
++fmt;
}
else if (*fmt == '\n')
{
/* See whether we have to print a single newline character. */
if (fmt == startp)
{
iov[niov].iov_base = (char *) startp;
iov[niov++].iov_len = 1;
}
else
/* No, just add it to the rest of the string. */
++iov[niov - 1].iov_len;
/* Next line, print a tag again. */
tag_p = 1;
++fmt;
}
}
/* Finally write the result. */
_dl_writev (fd, iov, niov);
}
/* Write to debug file. */
void
_dl_debug_printf (const char *fmt, ...)
{
va_list arg;
va_start (arg, fmt);
_dl_debug_vdprintf (GLRO(dl_debug_fd), 1, fmt, arg);
va_end (arg);
}
/* Write to debug file but don't start with a tag. */
void
_dl_debug_printf_c (const char *fmt, ...)
{
va_list arg;
va_start (arg, fmt);
_dl_debug_vdprintf (GLRO(dl_debug_fd), -1, fmt, arg);
va_end (arg);
}
/* Write the given file descriptor. */
void
_dl_dprintf (int fd, const char *fmt, ...)
{
va_list arg;
va_start (arg, fmt);
_dl_debug_vdprintf (fd, 0, fmt, arg);
va_end (arg);
}
void
_dl_printf (const char *fmt, ...)
{
va_list arg;
va_start (arg, fmt);
_dl_debug_vdprintf (STDOUT_FILENO, 0, fmt, arg);
va_end (arg);
}
void
_dl_error_printf (const char *fmt, ...)
{
va_list arg;
va_start (arg, fmt);
_dl_debug_vdprintf (STDERR_FILENO, 0, fmt, arg);
va_end (arg);
}
void
_dl_fatal_printf (const char *fmt, ...)
{
va_list arg;
va_start (arg, fmt);
_dl_debug_vdprintf (STDERR_FILENO, 0, fmt, arg);
va_end (arg);
_exit (127);
}
rtld_hidden_def (_dl_fatal_printf)
/* Test whether given NAME matches any of the names of the given object. */
int
_dl_name_match_p (const char *name, const struct link_map *map)
{
if (strcmp (name, map->l_name) == 0)
return 1;
struct libname_list *runp = map->l_libname;
while (runp != NULL)
if (strcmp (name, runp->name) == 0)
return 1;
else
runp = runp->next;
return 0;
}
unsigned long int
_dl_higher_prime_number (unsigned long int n)
{
/* These are primes that are near, but slightly smaller than, a
power of two. */
static const uint32_t primes[] = {
UINT32_C (7),
UINT32_C (13),
UINT32_C (31),
UINT32_C (61),
UINT32_C (127),
UINT32_C (251),
UINT32_C (509),
UINT32_C (1021),
UINT32_C (2039),
UINT32_C (4093),
UINT32_C (8191),
UINT32_C (16381),
UINT32_C (32749),
UINT32_C (65521),
UINT32_C (131071),
UINT32_C (262139),
UINT32_C (524287),
UINT32_C (1048573),
UINT32_C (2097143),
UINT32_C (4194301),
UINT32_C (8388593),
UINT32_C (16777213),
UINT32_C (33554393),
UINT32_C (67108859),
UINT32_C (134217689),
UINT32_C (268435399),
UINT32_C (536870909),
UINT32_C (1073741789),
UINT32_C (2147483647),
/* 4294967291L */
UINT32_C (2147483647) + UINT32_C (2147483644)
};
const uint32_t *low = &primes[0];
const uint32_t *high = &primes[sizeof (primes) / sizeof (primes[0])];
while (low != high)
{
const uint32_t *mid = low + (high - low) / 2;
if (n > *mid)
low = mid + 1;
else
high = mid;
}
#if 0
/* If we've run out of primes, abort. */
if (n > *low)
{
fprintf (stderr, "Cannot find prime bigger than %lu\n", n);
abort ();
}
#endif
return *low;
}
/* A stripped down strtoul-like implementation for very early use. It
does not set errno if the result is outside bounds because it may get
called before errno may have been set up. */
uint64_t
_dl_strtoul (const char *nptr, char **endptr)
{
uint64_t result = 0;
bool positive = true;
unsigned max_digit;
while (*nptr == ' ' || *nptr == '\t')
++nptr;
if (*nptr == '-')
{
positive = false;
++nptr;
}
else if (*nptr == '+')
++nptr;
if (*nptr < '0' || *nptr > '9')
{
if (endptr != NULL)
*endptr = (char *) nptr;
return 0UL;
}
int base = 10;
max_digit = 9;
if (*nptr == '0')
{
if (nptr[1] == 'x' || nptr[1] == 'X')
{
base = 16;
nptr += 2;
}
else
{
base = 8;
max_digit = 7;
}
}
while (1)
{
int digval;
if (*nptr >= '0' && *nptr <= '0' + max_digit)
digval = *nptr - '0';
else if (base == 16)
{
if (*nptr >= 'a' && *nptr <= 'f')
digval = *nptr - 'a' + 10;
else if (*nptr >= 'A' && *nptr <= 'F')
digval = *nptr - 'A' + 10;
else
break;
}
else
break;
if (result >= (UINT64_MAX - digval) / base)
{
if (endptr != NULL)
*endptr = (char *) nptr;
return UINT64_MAX;
}
result *= base;
result += digval;
++nptr;
}
if (endptr != NULL)
*endptr = (char *) nptr;
/* Avoid 64-bit multiplication. */
if (!positive)
result = -result;
return result;
}