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// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2022 Felix Fietkau <nbd@nbd.name>
*/
#include <sys/wait.h>
#include <unistd.h>
#include <stdio.h>
#include "dhcpsnoop.h"
int dhcpsnoop_run_cmd(char *cmd, bool ignore_error)
{
char *argv[] = { "sh", "-c", cmd, NULL };
bool first = true;
int status = -1;
char buf[512];
int fds[2];
FILE *f;
int pid;
if (pipe(fds))
return -1;
pid = fork();
if (!pid) {
close(fds[0]);
if (fds[1] != STDOUT_FILENO)
dup2(fds[1], STDOUT_FILENO);
if (fds[1] != STDERR_FILENO)
dup2(fds[1], STDERR_FILENO);
if (fds[1] > STDERR_FILENO)
close(fds[1]);
execv("/bin/sh", argv);
exit(1);
}
if (pid < 0)
return -1;
close(fds[1]);
f = fdopen(fds[0], "r");
if (!f) {
close(fds[0]);
goto out;
}
while (fgets(buf, sizeof(buf), f) != NULL) {
if (!strlen(buf))
break;
if (ignore_error)
continue;
if (first) {
ULOG_WARN("Command: %s\n", cmd);
first = false;
}
ULOG_WARN("%s%s", buf, strchr(buf, '\n') ? "" : "\n");
}
fclose(f);
out:
while (waitpid(pid, &status, 0) < 0)
if (errno != EINTR)
break;
return status;
}
int main(int argc, char **argv)
{
ulog_open(ULOG_STDIO | ULOG_SYSLOG, LOG_DAEMON, "udhcpsnoop");
uloop_init();
dhcpsnoop_ubus_init();
dhcpsnoop_dev_init();
ulog_threshold(LOG_INFO);
uloop_run();
dhcpsnoop_ubus_done();
dhcpsnoop_dev_done();
uloop_done();
return 0;
}
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