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+/* 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 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, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#ifndef _bp_checks_h_
+#define _bp_checks_h_ 1
+
+#if __BOUNDED_POINTERS__
+
+# define BOUNDS_VIOLATED (__builtin_trap (), 0)
+
+/* Verify that pointer's value >= low. Return pointer value. */
+# define CHECK_BOUNDS_LOW(ARG) \
+ (((__ptrvalue (ARG) < __ptrlow (ARG)) && BOUNDS_VIOLATED), \
+ __ptrvalue (ARG))
+
+/* Verify that pointer's value < high. Return pointer value. */
+# define CHECK_BOUNDS_HIGH(ARG) \
+ (((__ptrvalue (ARG) > __ptrhigh (ARG)) && BOUNDS_VIOLATED), \
+ __ptrvalue (ARG))
+
+# define _CHECK_N(ARG, N, COND) \
+ (((COND) \
+ && (__ptrvalue (ARG) < __ptrlow (ARG) \
+ || __ptrvalue (ARG) + (N) > __ptrhigh (ARG)) \
+ && BOUNDS_VIOLATED), \
+ __ptrvalue (ARG))
+
+extern void *__unbounded __ubp_memchr (const void *__unbounded, int, unsigned);
+
+# define _CHECK_STRING(ARG, COND) \
+ (((COND) \
+ && (__ptrvalue (ARG) < __ptrlow (ARG) \
+ || !__ubp_memchr (__ptrvalue (ARG), '\0', \
+ (__ptrhigh (ARG) - __ptrvalue (ARG)))) \
+ && BOUNDS_VIOLATED), \
+ __ptrvalue (ARG))
+
+/* Check bounds of a pointer seated to an array of N objects. */
+# define CHECK_N(ARG, N) _CHECK_N ((ARG), (N), 1)
+/* Same as CHECK_N, but tolerate ARG == NULL. */
+# define CHECK_N_NULL_OK(ARG, N) _CHECK_N ((ARG), (N), __ptrvalue (ARG))
+
+/* Check bounds of a pointer seated to a single object. */
+# define CHECK_1(ARG) CHECK_N ((ARG), 1)
+/* Same as CHECK_1, but tolerate ARG == NULL. */
+# define CHECK_1_NULL_OK(ARG) CHECK_N_NULL_OK ((ARG), 1)
+
+/* Check for NUL-terminator within string's bounds. */
+# define CHECK_STRING(ARG) _CHECK_STRING ((ARG), 1)
+/* Same as CHECK_STRING, but tolerate ARG == NULL. */
+# define CHECK_STRING_NULL_OK(ARG) _CHECK_STRING ((ARG), __ptrvalue (ARG))
+
+/* Check bounds of signal syscall args with type sigset_t. */
+# define CHECK_SIGSET(SET) CHECK_N ((SET), _NSIG / (8 * sizeof *(SET)))
+/* Same as CHECK_SIGSET, but tolerate SET == NULL. */
+# define CHECK_SIGSET_NULL_OK(SET) CHECK_N_NULL_OK ((SET), _NSIG / (8 * sizeof *(SET)))
+
+# if defined (_IOC_SIZESHIFT) && defined (_IOC_SIZEBITS)
+/* Extract the size of the ioctl data and check its bounds. */
+# define CHECK_IOCTL(ARG, CMD) \
+ CHECK_N ((const char *) (ARG), \
+ (((CMD) >> _IOC_SIZESHIFT) & ((1 << _IOC_SIZEBITS) - 1)))
+# else
+/* We don't know the size of the ioctl data, so the best we can do
+ is check that the first byte is within bounds. */
+# define CHECK_IOCTL(ARG, CMD) CHECK_1 ((const char *) ARG)
+# endif
+
+/* Check bounds of `struct flock *' for the locking fcntl commands. */
+# define CHECK_FCNTL(ARG, CMD) \
+ (((CMD) == F_GETLK || (CMD) == F_SETLK || (CMD) == F_SETLKW) \
+ ? CHECK_1 ((struct flock *) ARG) : (unsigned long) (ARG))
+
+/* Check bounds of an array of mincore residency-status flags that
+ cover a region of NBYTES. Such a vector occupies one byte per page
+ of memory. */
+# define CHECK_N_PAGES(ARG, NBYTES) \
+ ({ int _page_size_ = sysconf (_SC_PAGE_SIZE); \
+ CHECK_N ((const char *) (ARG), \
+ ((NBYTES) + _page_size_ - 1) / _page_size_); })
+
+/* Return a bounded pointer with value PTR that satisfies CHECK_N (PTR, N). */
+# define BOUNDED_N(PTR, N) \
+ ({ __typeof (PTR) __bounded _p_; \
+ __ptrvalue _p_ = __ptrlow _p_ = __ptrvalue (PTR); \
+ __ptrhigh _p_ = __ptrvalue _p_ + (N); \
+ _p_; })
+
+#else /* !__BOUNDED_POINTERS__ */
+
+/* Do nothing if not compiling with -fbounded-pointers. */
+
+# define BOUNDS_VIOLATED
+# define CHECK_BOUNDS_LOW(ARG) (ARG)
+# define CHECK_BOUNDS_HIGH(ARG) (ARG)
+# define CHECK_1(ARG) (ARG)
+# define CHECK_1_NULL_OK(ARG) (ARG)
+# define CHECK_N(ARG, N) (ARG)
+# define CHECK_N_NULL_OK(ARG, N) (ARG)
+# define CHECK_STRING(ARG) (ARG)
+# define CHECK_SIGSET(SET) (SET)
+# define CHECK_SIGSET_NULL_OK(SET) (SET)
+# define CHECK_IOCTL(ARG, CMD) (ARG)
+# define CHECK_FCNTL(ARG, CMD) (ARG)
+# define CHECK_N_PAGES(ARG, NBYTES) (ARG)
+# define BOUNDED_N(PTR, N) (PTR)
+
+#endif /* !__BOUNDED_POINTERS__ */
+
+#define BOUNDED_1(PTR) BOUNDED_N (PTR, 1)
+
+#endif /* _bp_checks_h_ */