/* xspan -- a minimally invasive checked memory smart pointer

   This file is part of the UPX executable compressor.

   Copyright (C) Markus Franz Xaver Johannes Oberhumer
   All Rights Reserved.

   UPX and the UCL library are free software; you can redistribute them
   and/or modify them under the terms of the GNU General Public License as
   published by the Free Software Foundation; either version 2 of
   the License, or (at your option) any later version.

   This program 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 General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; see the file COPYING.
   If not, write to the Free Software Foundation, Inc.,
   59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

   Markus F.X.J. Oberhumer
   <markus@oberhumer.com>
 */

#include "../conf.h"

#if WITH_XSPAN

XSPAN_NAMESPACE_BEGIN

// debugging stats
struct XSpanStats {
    upx_std_atomic(size_t) check_range_counter;
    // these usually will be zero, but internal doctest checks will populate them; see dt_xspan.cpp
    upx_std_atomic(size_t) fail_nullptr;
    upx_std_atomic(size_t) fail_nullbase;
    upx_std_atomic(size_t) fail_not_same_base;
    upx_std_atomic(size_t) fail_range_nullptr;
    upx_std_atomic(size_t) fail_range_nullbase;
    upx_std_atomic(size_t) fail_range_range;
};
static XSpanStats xspan_stats;

// HINT: set env-var "UPX_DEBUG_DOCTEST_DISABLE=1" for improved debugging experience
void xspan_fail_nullptr() may_throw {
    xspan_stats.fail_nullptr += 1;
    throwCantPack("xspan unexpected NULL pointer; take care!");
}
void xspan_fail_nullbase() may_throw {
    xspan_stats.fail_nullbase += 1;
    throwCantPack("xspan unexpected NULL base; take care!");
}
void xspan_fail_not_same_base() may_throw {
    xspan_stats.fail_not_same_base += 1;
    throwCantPack("xspan unexpected base pointer; take care!");
}

void xspan_fail_range_nullptr() may_throw {
    xspan_stats.fail_range_nullptr += 1;
    throwCantPack("xspan_check_range: unexpected NULL pointer; take care!");
}
void xspan_fail_range_nullbase() may_throw {
    xspan_stats.fail_range_nullbase += 1;
    throwCantPack("xspan_check_range: unexpected NULL base; take care!");
}
void xspan_fail_range_range() may_throw {
    xspan_stats.fail_range_range += 1;
    throwCantPack("xspan_check_range: pointer out of range; take care!");
}

void xspan_check_range(const void *ptr, const void *base, ptrdiff_t size_in_bytes) may_throw {
    xspan_stats.check_range_counter += 1;
    if very_unlikely (ptr == nullptr)
        xspan_fail_range_nullptr();
    if very_unlikely (base == nullptr)
        xspan_fail_range_nullbase();
    upx_sptraddr_t off = ptraddr_diff(ptr, base);
    if very_unlikely (off < 0 || off > size_in_bytes || size_in_bytes > UPX_RSIZE_MAX)
        xspan_fail_range_range();
    // NO_fprintf(stderr, "xspan_check_range done %zu\n", size_t(xspan_stats.check_range_counter));
}

XSPAN_NAMESPACE_END

#endif // WITH_XSPAN

/* vim:set ts=4 sw=4 et: */
