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// SPDX-License-Identifier: GPL-2.0
#define _GNU_SOURCE
#include <sys/uio.h>
#include <errno.h>
#include <stdio.h>
#include <sys/socket.h>
#include <fcntl.h>
#include <unistd.h>
#include "../../include/uapi/linux/bpf.h"
#include <asm/unistd.h>
#include "msgfmt.h"
FILE *debug_f;
static int handle_get_cmd(struct mbox_request *cmd)
{
switch (cmd->cmd) {
case 0:
return 0;
default:
break;
}
return -ENOPROTOOPT;
}
static int handle_set_cmd(struct mbox_request *cmd)
{
return -ENOPROTOOPT;
}
static void loop(void)
{
while (1) {
struct mbox_request req;
struct mbox_reply reply;
int n;
fprintf(debug_f, "testing the buffer\n");
n = read(0, &req, sizeof(req));
if (n != sizeof(req)) {
fprintf(debug_f, "invalid request %d\n", n);
return;
}
reply.status = req.is_set ?
handle_set_cmd(&req) :
handle_get_cmd(&req);
n = write(1, &reply, sizeof(reply));
if (n != sizeof(reply)) {
fprintf(debug_f, "reply failed %d\n", n);
return;
}
}
}
int main(void)
{
debug_f = fopen("/dev/kmsg", "w");
setvbuf(debug_f, 0, _IOLBF, 0);
fprintf(debug_f, "Started bpfilter\n");
loop();
fclose(debug_f);
return 0;
}
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