Added proper daemonization, bumped version number

src/wstationd.c

@@ -6,14 +6,17 @@
 #include <stdlib.h>
 #include <limits.h>
 #include <fcntl.h>
+#include <sys/stat.h>
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <sys/time.h>
+#include <sys/param.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include <libgen.h>
 #include <getopt.h>
 #include <poll.h>
+#include <syslog.h>
 #include "wstationd.h"
 
 
@@ -31,7 +34,9 @@
 #define TIMEOUT 30
 
 
-static char* exec_name;
+static char exec_name[MAXPATHLEN];
+
+static int daemonize = 1;
 
 struct connection 
 {
@@ -48,6 +53,7 @@ static int write_connection(struct connection *);
 static void print_help()
 {
 	fprintf(stdout, "usage: %s [-p port] [-b addr] directory\n", exec_name);
+	fprintf(stdout, "  -d, --nodaemon        Do not detach and daemonize\n");
 	fprintf(stdout, "  -p, --port <port>     Port to listen on (default: 10800)\n");
 	fprintf(stdout, "  -b, --bind <address>  Address to bind to (default: 0.0.0.0)\n");
 	fprintf(stdout, "  -h, --help            Print this message and exit\n");
@@ -58,6 +64,7 @@ static void print_help()
 int main(int argc, char* argv[])
 {
 	const struct option longopts[] = {
+		{ "nodaemon", required_argument, NULL, 'd' },
 		{ "port", required_argument, NULL, 'p' },
 		{ "bind", required_argument, NULL, 'b' },
 		{ "version", no_argument, NULL, 'v' },
@@ -72,13 +79,20 @@ int main(int argc, char* argv[])
 
 	struct connection* conns[SLOTLIMIT];
 	memset(conns, 0, sizeof(struct connection*) * SLOTLIMIT);
-	struct pollfd fds[SLOTLIMIT+1];
-	memset(&fds, 0, sizeof(struct pollfd) * (SLOTLIMIT + 1));
 
-	exec_name = basename(argv[0]);
+	if(basename_r(argv[0], exec_name) == NULL){
+		fprintf(stderr, "%s: cannot get basename - %s\n",
+			exec_name, strerror(errno)
+		);
+		goto shutdown_error;
+	}
 
-	for(int ch; (ch = getopt_long(argc, argv, "l:b:p:vh0", longopts, NULL)) != -1;){
+	for(int ch; (ch = getopt_long(argc, argv, "l:b:p:dvh0", longopts, NULL)) != -1;){
 		switch(ch){
+			case 'd':
+				daemonize = 0;
+			break;
+			
 			case 'p':
 				port = (int)strtol(optarg, NULL, 10);
 				if(port < 1 || port > 65535){
@@ -121,13 +135,57 @@ int main(int argc, char* argv[])
 		goto shutdown_error;
 	}
 
+	// Daemonize if requested
+	if(daemonize){
+		pid_t pid = fork();
+
+		// Fork failure
+		if(pid == -1){
+			fprintf(stderr, "%s: cannot fork - %s\n",
+				exec_name, strerror(errno)
+			);
+			goto shutdown_error;
+		}
+
+		// Fork success, exit parent process
+		if(pid > 0){ exit(EXIT_SUCCESS); }
+
+		// create new session for daemon
+		if(setsid() == -1){
+			fprintf(stderr, "%s: cannot setsid - %s\n",
+				exec_name, strerror(errno)
+			);
+			goto shutdown_error;
+		}
+		
+		// Ensure that standard descriptors are
+		// unavailable after fork() and setsid()
+		int fd = open("/dev/null", O_RDWR, 0);
+		if(fd != -1){
+			dup2(fd, fileno(stdin));
+			dup2(fd, fileno(stdout));
+			dup2(fd, fileno(stderr));
+		}
+
+		// Open syslog
+		openlog(exec_name, LOG_PID, LOG_DAEMON);
+	}
+
+	// Change default mask
+	umask(133);
 
 	// Establish the socket
 	sockfd = socket(AF_INET, SOCK_STREAM, 0);
 	if(sockfd == -1){
+		if(daemonize){
+			syslog(LOG_ERR, "cannot open socket - %s",
+				strerror(errno)
+			);
+		} else {
 			fprintf(stderr, "%s: cannot open socket - %s\n",
 				exec_name, strerror(errno)
 			);
+		}
 		goto shutdown_error;
 	}
 
@@ -144,32 +202,51 @@ int main(int argc, char* argv[])
 
 	// Bind our socket to the specified address and port
 	if(bind(sockfd, (struct sockaddr*)&sock, sizeof(sock)) < 0){
+		if(daemonize){
+			syslog(LOG_ERR, "cannot bind - %s",
+				strerror(errno)
+			);
+		} else {
 			fprintf(stderr, "%s: cannot bind - %s\n",
 				exec_name, strerror(errno)
 			);
+		}
 		goto shutdown_error;
 	}
 
 	// Listen on port
 	if(listen(sockfd, 10) != 0){
+		if(daemonize){
+			syslog(LOG_ERR, "cannot listen - %s",
+				strerror(errno)
+			);
+		} else {
 			fprintf(stderr, "%s: cannot listen - %s\n",
 				exec_name, strerror(errno)
 			);
+		}
 		goto shutdown_error;
 	}
 
+	struct pollfd fds[SLOTLIMIT+1];
+	memset(&fds, 0, sizeof(struct pollfd) * (SLOTLIMIT + 1));
+
 	// Add sockfd
 	fds[0].fd = sockfd;
 	fds[0].events = POLLIN;
 	fds[0].revents = 0;
 
 	while(1){
-		int r = poll(fds, (SLOTLIMIT + 1), 1000);
+		if(poll(fds, (SLOTLIMIT + 1), 1000) == -1){
-
+			if(daemonize){
-		if(r == -1){
+				syslog(LOG_ERR, "socket poll error - %s",
+					strerror(errno)
+				);
+			} else {
 				fprintf(stderr, "%s: socket poll error - %s\n",
 					exec_name, strerror(errno)
 				);
+			}
 			goto shutdown_error;
 		}
 
@@ -238,26 +315,44 @@ int main(int argc, char* argv[])
 
 			int fd = accept(sockfd, (struct sockaddr*)&client, &client_sz);
 			if(fd == -1){
+				if(daemonize){
+					syslog(LOG_ERR, "accept failed - %s",
+						strerror(errno)
+					);
+				} else {
 					fprintf(stderr, "%s: accept failed - %s\n",
 						exec_name, strerror(errno)
 					);
+				}
 				continue;
 			}
 			
 			// Get current flags before setting nonblock
 			if((flags = fcntl(fd, F_GETFL)) == -1){
+				if(daemonize){
+					syslog(LOG_ERR, "cannot get connection flags - %s",
+						strerror(errno)
+					);
+				} else {
 					fprintf(stderr, "%s: cannot get connection flags - %s\n",
 						exec_name, strerror(errno)
 					);
+				}
 				close(fd);
 				continue;
 			}
 
 			// Set nonblocking on socket
 			if(fcntl(fd, F_SETFL, flags | O_NONBLOCK) == -1){
+				if(daemonize){
+					syslog(LOG_ERR, "cannot set connection flags - %s",
+						strerror(errno)
+					);
+				} else {
 					fprintf(stderr, "%s: cannot set connection flags - %s\n",
 						exec_name, strerror(errno)
 					);
+				}
 				close(fd);
 				continue;
 			}
@@ -265,7 +360,11 @@ int main(int argc, char* argv[])
 			// Allocate memory for the connection's state. 
 			conns[slotfirst - 1] = malloc(sizeof(struct connection));
 			if(conns[slotfirst - 1] == NULL){
+				if(daemonize){
+					syslog(LOG_ERR, "out of memory");
+				} else {
 					fprintf(stderr, "%s: out of memory\n", exec_name);
+				}
 				close(fd);
 				continue;
 			}
@@ -296,6 +395,7 @@ int main(int argc, char* argv[])
 
 	shutdown_error:
 	if(sockfd > 0) close(sockfd);
+	for(int i = 0; i < SLOTLIMIT; i++){ if(conns[i] != NULL) free(conns[i]); }
 	return 1;
 }
 
@@ -305,8 +405,9 @@ static int write_connection(struct connection *conn)
 	// Build a filename for the file we're writing based
 	// on the time and the source IP address
 	char timebuff[20];
-	struct tm* timeptr = localtime(&conn->tv.tv_sec);
+	struct tm timeptr;
-	strftime(&timebuff[0], 20, "%Y%m%d%H%M%S", timeptr);
+	localtime_r(&conn->tv.tv_sec, &timeptr);
+	strftime(&timebuff[0], 20, "%Y%m%d%H%M%S", &timeptr);
 
 	char fnbuff[50];
 	snprintf(&fnbuff[0], 50, "%s.%ld-%s.dat",
@@ -316,16 +417,29 @@ static int write_connection(struct connection *conn)
 
 	int ofd;
 	if((ofd = open(fnbuff, O_WRONLY | O_CREAT, 0644)) == -1){
-		fprintf(stderr, "%s: cannot open - %s\n",
+		if(daemonize){
-			exec_name, strerror(errno)
+			syslog(LOG_ERR, "cannot open %s - %s",
+				fnbuff, strerror(errno)
 			);
+		} else {
+			fprintf(stderr, "%s: cannot open %s - %s\n",
+				exec_name, fnbuff, strerror(errno)
+			);
+		}
 		return 1;
 	}
 
+	// Write out the buffer
 	if(write(ofd, conn->buff, conn->len) == -1){
-		fprintf(stderr, "%s: file write error - %s\n",
+		if(daemonize){
-			exec_name, strerror(errno)
+			syslog(LOG_ERR, "write error on %s - %s",
+				fnbuff, strerror(errno)
 			);
+		} else {
+			fprintf(stderr, "%s: write error on %s - %s\n",
+				exec_name, fnbuff, strerror(errno)
+			);
+		}
 		close(ofd);
 		return 1;
 	}

src/wstationd.h

@@ -1 +1 @@
-#define VERSION "0.7.0"
+#define VERSION "1.0.0"