X-Git-Url: http://git.jankratochvil.net/?p=inetdmx.git;a=blobdiff_plain;f=inetdmx.c;h=c6d961b4fb88a19f4e8eeb26cd817ba558af4a1e;hp=99077b9c2e0485cd174dee4bb7b7272bea162c35;hb=2e9dd08cf5766960c26a097ed8db740a018ba739;hpb=bc336bd45448b5761967792c416d56f84536e95a

diff --git a/inetdmx.c b/inetdmx.c
index 99077b9..c6d961b 100644
--- a/inetdmx.c
+++ b/inetdmx.c
@@ -171,11 +171,11 @@ static void usage(void)
 	fprintf(stderr,"\
 Syntax: %s {-1|--start} [{-T|--start-command-timeout} <start-command-timeout>]\n\
         \t[{-l|--lock} <filename>] [-S|--syslog] [-e|--stderr]\n\
-        \t\[-I|--ignore-spawned-command-output]\n\
+        \t[-I|--ignore-spawned-command-output]\n\
         \t{-p|--port} <server-port> <start-server-command>\n\
      or %s {-0|--stop}  [{-i|--idle-server-timeout} <idle-server-timeout>]\n\
         \t[{-l|--lock} <filename>] [-S|--syslog] [-e|--stderr]\n\
-        \t\[-I|--ignore-spawned-command-output]\n\
+        \t[-I|--ignore-spawned-command-output]\n\
         \t<stop-server-command>\n\
 \n\
 Error messages are printed to stderr by default,\n\
@@ -210,21 +210,35 @@ static void sighandler_flock_timeout(int signo)
 	sighandler_flock_timeout_hit=1;
 }
 
-static int lock_create(int lock_mode)
+enum lock_create_rc {
+	LOCK_CREATE_NO_LOCK_FILENAME,
+	LOCK_CREATE_FILE_NOT_FOUND,		/* only if: lock_mode&LOCK_NB */
+	LOCK_CREATE_ALREADY_LOCKED,		/* only if: lock_mode&LOCK_NB */
+	LOCK_CREATE_MYSELF_LOCKED,		/* only for: lock_create() */
+	LOCK_CREATE_MYSELF_LOCKED_AND_FRESH,	/* only for: lock_open_and_time_check() */
+	LOCK_CREATE_MYSELF_LOCKED_AND_STALE,	/* only for: lock_open_and_time_check() */
+	};
+/* It will never create the lock file if: lock_mode&LOCK_NB */
+static enum lock_create_rc lock_create(int lock_mode)
 {
 int retries=3;
 sighandler_t sighandler_alrm_orig;
 int flock_rc;
 
 	if (!opt_lock)
-		return 1;
+		return LOCK_CREATE_NO_LOCK_FILENAME;
 	/* Never drop the lock if the lock is already being held. */
 	if (lock_fd!=-1)
 		retries=-1;
 retry:
 	if (lock_fd==-1) {
-		if (-1==(lock_fd=open(opt_lock,O_CREAT|O_RDWR,0600)))
+		if (-1==(lock_fd=open(opt_lock,
+				O_RDWR | (lock_mode&LOCK_NB ? 0 : O_CREAT),
+				0600))) {
+			if (errno==ENOENT && lock_mode&LOCK_NB)
+				return LOCK_CREATE_FILE_NOT_FOUND;
 			fatal("Error creating lock file \"%s\": %m",opt_lock);
+			}
 		}
 	sighandler_alrm_orig=signal(SIGALRM,sighandler_flock_timeout);
 	alarm(opt_start_command_timeout+FLOCK_TIMEOUT_OVER_START_TIMEOUT);
@@ -235,7 +249,7 @@ retry:
 		fatal("Timeout locking lock file \"%s\": %m",opt_lock);
 	if (flock_rc) {
 		if (lock_mode&LOCK_NB && errno==EWOULDBLOCK)
-			return 0;
+			return LOCK_CREATE_ALREADY_LOCKED;
 		fatal("Error locking lock file \"%s\": %m",opt_lock);
 		}
 	if (access(opt_lock,R_OK|W_OK)) {
@@ -246,7 +260,7 @@ retry:
 		lock_fd=-1;
 		goto retry;
 		}
-	return 1;
+	return LOCK_CREATE_MYSELF_LOCKED;
 }
 
 static void lock_touch(void)
@@ -307,7 +321,7 @@ static void session_transfer(
 {
 struct pollfd pollfdi[2];
 int pollfdo[2];
-const char *pollfdi_name[2];
+const char *pollfd_name[2];
 int fdi,fdo;
 
 	pollfdi[0].fd=conn0_fdin;
@@ -316,18 +330,18 @@ int fdi,fdo;
 	pollfdi[1].events=POLLIN;
 	pollfdo[0]=conn0_fdout;
 	pollfdo[1]=conn1_fdout;
-	pollfdi_name[0]=conn0_name;
-	pollfdi_name[1]=conn1_name;
+	pollfd_name[0]=conn0_name;
+	pollfd_name[1]=conn1_name;
 	for (;;) {
 		if (0>=poll(pollfdi,G_N_ELEMENTS(pollfdi),-1))
-			fatal("poll(%s socket,%s socket): %m",pollfdi_name[0],pollfdi_name[1]);
+			fatal("poll(%s socket,%s socket): %m",pollfd_name[0],pollfd_name[1]);
 		for (fdi=0;fdi<G_N_ELEMENTS(pollfdi);fdi++)
 			if (0
 					||   pollfdi[fdi].revents & (POLLERR|POLLHUP|POLLNVAL)
 					|| ((pollfdi[fdi].revents & POLLIN) && !(pollfdi[fdi].events & POLLIN))
 					)
 				fatal("poll(%s socket): revents=0x%X (events=0x%X)",
-						pollfdi_name[fdi],(unsigned)pollfdi[fdi].revents,
+						pollfd_name[fdi],(unsigned)pollfdi[fdi].revents,
 						(unsigned)pollfdi[fdi].events);
 		for (fdi=0;fdi<G_N_ELEMENTS(pollfdi);fdi++) {
 			for (;;) {
@@ -335,26 +349,26 @@ int fdi,fdo;
 				char buf[SESSION_BUFFER_SIZE];
 
 				if (fcntl(pollfdi[fdi].fd,F_SETFL,O_NONBLOCK))
-					fatal("fcntl(%s socket,F_SETFL,O_NONBLOCK): %m",pollfdi_name[fdi]);
+					fatal("fcntl(%s socket,F_SETFL,O_NONBLOCK): %m",pollfd_name[fdi]);
 				got=read(pollfdi[fdi].fd,buf,sizeof(buf));
 				if (got<0) {
 					if (errno==EAGAIN)
 						break;
-					fatal("read(%s socket): %m",pollfdi_name[fdi]);
+					fatal("read(%s socket): %m",pollfd_name[fdi]);
 					}
 				if (got==0) {
 					lock_close();
 					exit(EXIT_SUCCESS);
 					}
-				for (fdo=0;fdo<G_N_ELEMENTS(pollfdi);fdo++) {
+				for (fdo=0;fdo<G_N_ELEMENTS(pollfdo);fdo++) {
 					if (fdi==fdo)
 						continue;
-					if (fcntl(pollfdi[fdo].fd,F_SETFL,0 /* !O_NONBLOCK */))
+					if (fcntl(pollfdo[fdo],F_SETFL,0 /* !O_NONBLOCK */))
 						fatal("fcntl(%s socket,F_SETFL,0 /* !O_NONBLOCK */): %m",
-								pollfdi_name[fdo]);
-					if (got!=write(pollfdi[fdo].fd,buf,got))
+								pollfd_name[fdo]);
+					if (got!=write(pollfdo[fdo],buf,got))
 						fatal("write(%s socket,%ld): %m",
-								pollfdi_name[fdo],(long)got);
+								pollfd_name[fdo],(long)got);
 					}
 				}
 			}
@@ -470,24 +484,17 @@ int retry;
 			opt_start_command_timeout,opt_port,opt_command);
 }
 
-/* Returns: Is fresh or does not exist? */
-static int lock_open_and_time_check(int lock_mode)
+static enum lock_create_rc lock_open_and_time_check(int lock_mode)
 {
+enum lock_create_rc rc;
 struct stat statbuf;
 
-	if (!opt_lock)
-		return 0;
-
-	if (access(opt_lock,R_OK|W_OK)) {
-		if (errno==ENOENT)
-			return 1;
-		fatal("Error checking existance of the lock file \"%s\": %m",opt_lock);
-		}
-	if (!lock_create(lock_mode|LOCK_NB))
-		return 0;
+	if (LOCK_CREATE_MYSELF_LOCKED!=(rc=lock_create(lock_mode|LOCK_NB)))
+		return rc;
 	if (lock_fd==-1 || fstat(lock_fd,&statbuf))
 		fatal("Error fstat(2)ting lock file \"%s\": %m",opt_lock);
-	return statbuf.st_mtime>=time(NULL)-opt_idle_server_timeout;
+	return (statbuf.st_mtime>=time(NULL)-opt_idle_server_timeout
+			? LOCK_CREATE_MYSELF_LOCKED_AND_FRESH : LOCK_CREATE_MYSELF_LOCKED_AND_STALE);
 }
 
 static void lock_delete_and_close(void)
@@ -498,10 +505,22 @@ static void lock_delete_and_close(void)
 	lock_close();
 }
 
+static void lock_open_and_return_if_stale(int lock_mode)
+{
+	switch (lock_open_and_time_check(lock_mode)) {
+		case LOCK_CREATE_NO_LOCK_FILENAME:        return;
+		case LOCK_CREATE_FILE_NOT_FOUND:          exit(EXIT_SUCCESS);
+		case LOCK_CREATE_ALREADY_LOCKED:          exit(EXIT_SUCCESS);
+		case LOCK_CREATE_MYSELF_LOCKED:           assert(0);
+		case LOCK_CREATE_MYSELF_LOCKED_AND_FRESH: exit(EXIT_SUCCESS);
+		case LOCK_CREATE_MYSELF_LOCKED_AND_STALE: return;
+		}
+	assert(0);
+}
+
 static void stop(void) G_GNUC_NORETURN;
 static void stop(void)
 {
-int is_fresh;
 
 	/* Lock still being held! */
 	if (opt_port)
@@ -511,12 +530,10 @@ int is_fresh;
 	if (opt_idle_server_timeout!=DEFAULT_IDLE_SERVER_TIMEOUT && !opt_lock)
 		fatal("-l|--lock is a required argument for -i|--idle-server-timeout of -1|--start");
 
-	is_fresh=lock_open_and_time_check(LOCK_SH);
+	lock_open_and_return_if_stale(LOCK_SH);
 	lock_close();
-	if (is_fresh)
-		exit(EXIT_SUCCESS);
 
-	lock_open_and_time_check(LOCK_EX);
+	lock_open_and_return_if_stale(LOCK_EX);
 	system_checked(opt_command);
 	lock_delete_and_close();