summaryrefslogtreecommitdiff
path: root/package/uvd/src
diff options
context:
space:
mode:
authorWaldemar Brodkorb <wbx@openadk.org>2010-07-02 15:30:56 +0200
committerWaldemar Brodkorb <wbx@openadk.org>2010-07-02 15:30:56 +0200
commit3fc7c024cf716efa0d2d70fc33412b70b870146b (patch)
tree88f96f5f0b44d0644a227933b72e3de8b35ce972 /package/uvd/src
parent6b6b7abab1ffe76a87fd46623c1d026d4f25862f (diff)
add a small udp based daemon
Diffstat (limited to 'package/uvd/src')
-rw-r--r--package/uvd/src/uvd.c237
1 files changed, 237 insertions, 0 deletions
diff --git a/package/uvd/src/uvd.c b/package/uvd/src/uvd.c
new file mode 100644
index 000000000..f41a5c885
--- /dev/null
+++ b/package/uvd/src/uvd.c
@@ -0,0 +1,237 @@
+/*
+ * daemon for version information of embedded systems
+ *
+ * Copyright (C) 2010 Waldemar Brodkorb <wbx@openadk.org>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it 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; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ */
+
+#include <arpa/inet.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <netinet/in.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <time.h>
+#include <unistd.h>
+
+#define VERSION "0.1"
+#define LOGFILE "/tmp/uvd.log"
+#define LOCKFILE "/tmp/uvd.lock"
+#define BUFSIZE 1024
+#define VERFILE "/etc/adkversion"
+
+void version() {
+ fprintf(stdout, "uvd version %s", VERSION);
+ exit(EXIT_SUCCESS);
+}
+
+static const char *log_date(void) {
+ static char buf[18];
+ time_t t = time(NULL);
+ strftime(buf, 18, "%b %d %H:%M:%S", localtime(&t));
+ return buf;
+}
+
+void die(const char *msg) {
+ fprintf(stderr, "%s\n", msg);
+ exit(EXIT_FAILURE);
+}
+
+void die_log(FILE *lf, const char *msg) {
+ fprintf(lf, "%s: %s\n", log_date(), msg);
+ exit(EXIT_FAILURE);
+}
+
+void log_msg(FILE *lf, const char *msg) {
+ fprintf(lf, "%s: %s\n", log_date(), msg);
+ fflush(lf);
+}
+
+
+void signal_handler(int sig) {
+
+ switch(sig) {
+ case SIGHUP:
+ break;
+ case SIGTERM:
+ case SIGINT:
+ case SIGQUIT:
+ unlink(LOCKFILE);
+ exit(EXIT_SUCCESS);
+ break;
+ default:
+ break;
+ }
+}
+
+void usage(int argc, char *argv[]) {
+
+ if (argc >=1) {
+ fprintf(stdout, "Usage: %s [ --help | --debug | --version ]\n", argv[0]);
+ fprintf(stdout, " Options:\n");
+ fprintf(stdout, " --debug | -d start in debug mode, don't fork\n");
+ fprintf(stdout, " --version | -v show version\n");
+ fprintf(stdout, " --help | -h show help\n");
+ fprintf(stdout, "\n");
+ }
+ exit(EXIT_SUCCESS);
+}
+
+
+int main(int argc, char **argv) {
+
+ pid_t pid, sid;
+ int lfd, c, ss, n, res;
+ FILE *lf = NULL;
+ int vf;
+ struct sigaction sigact;
+ int daemonize = 1;
+ int optval = 1;
+ char buf[BUFSIZE];
+ struct sockaddr_in server = { 0 };
+ struct sockaddr_in clientaddr; /* client addr */
+ socklen_t clientlen;
+
+ /* options descriptor */
+ static struct option longopts[] = {
+ { "debug", no_argument, 0, 'd' },
+ { "help", no_argument, 0, 'h' },
+ { "version", no_argument, 0, 'v' },
+ { NULL, 0, NULL, 0 }
+ };
+
+ while((c = getopt_long(argc, argv, "dhv", longopts, NULL)) != -1) {
+ switch(c) {
+ case 'h':
+ usage(argc, argv);
+ break;
+ case 'v':
+ version();
+ break;
+ case 'd':
+ daemonize = 0;
+ break;
+ default:
+ usage(argc, argv);
+ }
+ }
+
+ if (daemonize) {
+ /* Fork off the parent process */
+ pid = fork();
+ if (pid < 0)
+ die("Can't fork process");
+
+ /* If we got a pid, we exit the parent process */
+ if (pid > 0)
+ exit(EXIT_SUCCESS);
+
+ /* Change the file mode mask */
+ umask(0);
+ }
+
+ /* Open a logfile */
+ lf = fopen(LOGFILE, "a");
+ if (lf == NULL)
+ die("Can't open logfile");
+
+ if (daemonize) {
+ /* Create a new session for child process */
+ if ((sid = setsid()) < 0);
+ die_log(lf, "Can't create a new session for child process");
+
+ /* Change the current working directory */
+ if ((chdir("/")) < 0)
+ die_log(lf, "Can't change working directory to /");
+ }
+
+ /* check if daemon already running */
+ if ((lfd = open(LOCKFILE, O_RDWR | O_CREAT, 0640) < 0))
+ die("Can't open or create lock file");
+
+ if (lockf(lfd, F_TLOCK, 0) == -1)
+ die("uvd already running!");
+
+ if (daemonize) {
+ /* Close out the standard file descriptors */
+ close(STDIN_FILENO);
+ close(STDOUT_FILENO);
+ close(STDERR_FILENO);
+ }
+
+ /* Handle some signals */
+ sigact.sa_handler = signal_handler;
+ sigact.sa_flags = 0;
+
+ sigaction(SIGHUP, &sigact, NULL);
+ sigaction(SIGTERM, &sigact, NULL);
+ sigaction(SIGINT, &sigact, NULL);
+ sigaction(SIGQUIT, &sigact, NULL);
+
+ log_msg(lf, "uvd started successfully");
+
+ /* create network socket */
+ if ((ss = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP)) == -1)
+ die("can not create socket");
+
+ server.sin_addr.s_addr=htonl(INADDR_ANY);
+ server.sin_family = AF_INET;
+ server.sin_port = htons(4242);
+
+ if (setsockopt (ss, SOL_SOCKET, SO_BROADCAST, (caddr_t) &optval, sizeof (optval)) < 0)
+ die("can not set socket option");
+
+ if (setsockopt (ss, SOL_SOCKET, SO_REUSEADDR, (caddr_t) &optval, sizeof (optval)) < 0)
+ die("can not set socket option");
+
+ if (bind(ss, (struct sockaddr *) &server, sizeof(server)) < 0)
+ die("can not bind socket");
+
+ /* loop forever */
+ while(1) {
+ clientlen = sizeof(clientaddr);
+ n = recvfrom(ss, buf, BUFSIZE , 0, (struct sockaddr *)&clientaddr, &clientlen);
+ if (n < 0)
+ die_log(lf, "error reading from client");
+
+ buf[n] = 0;
+ res = strncmp(buf, "version", n);
+ if (res > 0) {
+ log_msg(lf, "been asked for version information");
+ if ((vf = open(VERFILE, O_RDONLY)) < 0)
+ die_log(lf, "unable to open version file");
+
+ ssize_t num;
+ do {
+ num = read(vf, &buf, sizeof(buf));
+ buf[num] = '\0';
+ if (sendto(ss, buf, num, 0, (struct sockaddr *) &clientaddr, sizeof(clientaddr)) < 0)
+ die_log(lf, "can not send data");
+ } while (num > 0);
+
+ close(vf);
+ }
+ }
+ close(ss);
+ return(0);
+}