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/*
* Copyright 2016-2017, 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.
*/
/*
* fork_logging.c -- dummy program, to issue fork via libc
*/
#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sched.h>
#include <sys/wait.h>
#include <pthread.h>
#include "magic_syscalls.h"
static const char *log_parent;
static const char *log_child;
static void *
busy(void *arg)
{
FILE *f;
const char *path = (const char *)arg;
char buffer[0x100];
size_t s;
if ((f = fopen(path, "r")) == NULL)
exit(EXIT_FAILURE);
s = fread(buffer, 1, sizeof(buffer), f);
if (s < 4)
exit(EXIT_FAILURE);
fwrite(buffer, 1, 1, stdout);
fflush(stdout);
fwrite(buffer, 2, 1, stdout);
fflush(stdout);
fwrite(buffer, 3, 1, stdout);
fflush(stdout);
putchar('\n');
fflush(stdout);
puts("Done being busy here");
fflush(stdout);
fclose(f);
magic_syscall_stop_log();
return NULL;
}
int
main(int argc, char *argv[])
{
if (argc < 4)
return EXIT_FAILURE;
log_parent = argv[2];
log_child = argv[3];
magic_syscall_start_log(log_parent, "1");
int r = fork();
if (r < 0)
err(EXIT_FAILURE, "fork");
if (r == 0) {
magic_syscall_start_log(log_child, "1");
busy(argv[1]);
} else {
wait(NULL);
busy(argv[1]);
}
magic_syscall_stop_log();
return EXIT_SUCCESS;
}