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/*
* Copyright 2017, Intel Corporation
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* * Neither the name of the copyright holder nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifdef NDEBUG
#undef NDEBUG
#endif
#include <assert.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <syscall.h>
#include <stdio.h>
#include "libsyscall_intercept_hook_point.h"
#include "hook_test_data.h"
static int hook_counter;
static bool in_hook;
static bool deinit_called;
static int
hook(long syscall_number, long arg0, long arg1, long arg2, long *result)
{
switch (hook_counter++) {
case 0:
/* fallthrough */
case 2:
assert(syscall_number == SYS_write);
assert(arg0 == hook_test_fd);
assert(strcmp((void *)(intptr_t)arg1, dummy_data) == 0);
assert(arg2 == (long)sizeof(dummy_data));
*result = hook_test_dummy_return_value;
return 0;
case 1:
assert(syscall_number == SYS_write);
assert(arg0 == hook_test_fd);
return 1;
default:
assert(0);
}
}
static int
hook_wrapper(long syscall_number,
long arg0, long arg1,
long arg2, long arg3,
long arg4, long arg5,
long *result)
{
(void) arg3;
(void) arg4;
(void) arg5;
if (in_hook || deinit_called)
return 1;
if (is_spurious_syscall(syscall_number, arg0))
return 1;
in_hook = true;
int ret = hook(syscall_number, arg0, arg1, arg2, result);
in_hook = false;
return ret;
}
static __attribute__((constructor)) void
init(void)
{
intercept_hook_point = hook_wrapper;
}
static __attribute__((destructor)) void
deinit(void)
{
deinit_called = true;
assert(hook_counter == 3);
}