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Diffstat (limited to 'package/uvd/src/uvd.c')
| -rw-r--r-- | package/uvd/src/uvd.c | 237 |
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..72d7980c1 --- /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); +} |