glibc/sysdeps/generic/bp-start.h

73 lines
2.6 KiB
C
Raw Normal View History

/* Bounded-pointer checking macros for C.
Copyright (C) 2000 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Greg McGary <greg@mcgary.org>
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., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#if __BOUNDED_POINTERS__
/* The command-line arg vector and environment vector come to us from
the OS as an unbounded pointer to an array of unbounded strings.
The user's main expects argv and __environ to be bounded pointers
to arrays of bounded strings. */
# define INIT_ARGV_and_ENVIRON \
do { \
int envc; \
for (envc = 0; *ubp_ev; ubp_ev++, envc++) \
; \
ubp_ev -= envc; \
\
/* GKM FIXME: we could save some space by allocating only enough for \
the additional low & high words, and destructively rewriting \
argv in place. */ \
__ptrvalue (argv) = __ptrlow (argv) \
= alloca ((argc + envc + 2) * sizeof (*argv)); \
__ptrhigh (argv) = __ptrvalue (argv) + argc + 1; \
__ptrvalue (__environ) = __ptrlow (__environ) = __ptrhigh (argv); \
__ptrhigh (__environ) = __ptrvalue (__environ) + envc + 1; \
boundify_vector (__environ, ubp_ev); \
boundify_vector (argv, ubp_av); \
} while (0)
/* Copy an unbounded vector of unbounded strings into a bounded
counterpart. */
static void
boundify_vector (char **dest, char *__unbounded *__unbounded src)
{
char *__unbounded s;
for (; *src; src++, dest++)
{
__ptrvalue (*dest) = __ptrlow (*dest) = *src;
__ptrhigh (*dest) = src[1];
}
*dest = 0;
/* The OS lays out strings contiguously in vector order,
so */
for (s = __ptrvalue (dest[-1]); *s; s++)
;
__ptrhigh (dest[-1]) = ++s;
}
#else
# define INIT_ARGV_and_ENVIRON __environ = ubp_ev
#endif