I think I might havefinally fixed the rsync hanging bug. It was caused

by a read during an io_flush() triggered during a readfd(). A simple
logic bug in the io code :(

io.c

@@ -70,6 +70,7 @@ static char *read_buffer_p;
 static int read_buffer_len;
 static int read_buffer_size;
 static int no_flush;
+static int no_flush_read;
 
 /* read from a socket with IO timeout. return the number of
    bytes read. If no bytes can be read then exit, never return
@@ -78,7 +79,9 @@ static int read_timeout(int fd, char *buf, int len)
 {
 	int n, ret=0;
 
+	no_flush_read++;
 	io_flush();
+	no_flush_read--;
 
 	while (ret == 0) {
 		fd_set fds;
@@ -254,7 +257,9 @@ static void readfd(int fd,char *buffer,int N)
 			continue;
 		} 
 
+		no_flush_read++;
 		io_flush();
+		no_flush_read--;
 
 		ret = read_unbuffered(fd,buffer + total,N-total);
 		total += ret;
@@ -320,7 +325,7 @@ static void writefd_unbuffered(int fd,char *buf,int len)
 	fd_set w_fds, r_fds;
 	int fd_count, count;
 	struct timeval tv;
-	int reading;
+	int reading=0;
 	int blocked=0;
 
 	no_flush++;
@@ -331,8 +336,10 @@ static void writefd_unbuffered(int fd,char *buf,int len)
 		FD_SET(fd,&w_fds);
 		fd_count = fd+1;
 
-		reading = (buffer_f_in != -1 && 
-			   read_buffer_len < MAX_READ_BUFFER);
+		if (!no_flush_read) {
+			reading = (buffer_f_in != -1 && 
+				   read_buffer_len < MAX_READ_BUFFER);
+		}
 
 		if (reading) {
 			FD_SET(buffer_f_in,&r_fds);

rsync.c

@@ -961,7 +961,7 @@ int recv_files(int f_in,struct file_list *flist,char *local_name,int f_gen)
 
 		if (!get_tmpname(fnametmp,fname)) {
 			if (buf) unmap_file(buf);
-			close(fd1);
+			if (fd1 != -1) close(fd1);
 			continue;
 		}
 
@@ -969,7 +969,7 @@ int recv_files(int f_in,struct file_list *flist,char *local_name,int f_gen)
 			rprintf(FERROR,"mktemp %s failed\n",fnametmp);
 			receive_data(f_in,buf,-1,NULL,file->length);
 			if (buf) unmap_file(buf);
-			close(fd1);
+			if (fd1 != -1) close(fd1);
 			continue;
 		}
 
@@ -990,7 +990,7 @@ int recv_files(int f_in,struct file_list *flist,char *local_name,int f_gen)
 			rprintf(FERROR,"open %s : %s\n",fnametmp,strerror(errno));
 			receive_data(f_in,buf,-1,NULL,file->length);
 			if (buf) unmap_file(buf);
-			close(fd1);
+			if (fd1 != -1) close(fd1);
 			continue;
 		}
       

socket.c

@@ -283,21 +283,19 @@ void become_daemon(void)
 {
 	int i;
 
-	if (fork())
+	if (fork()) {
 		_exit(0);
+	}
 
 	/* detach from the terminal */
 #ifdef HAVE_SETSID
 	setsid();
 #else
 #ifdef TIOCNOTTY
-	{
-		int i = open("/dev/tty", O_RDWR);
-		if (i >= 0) 
-			{
-				ioctl(i, (int) TIOCNOTTY, (char *)0);      
-				close(i);
-			}
+	i = open("/dev/tty", O_RDWR);
+	if (i >= 0) {
+		ioctl(i, (int) TIOCNOTTY, (char *)0);      
+		close(i);
 	}
 #endif /* TIOCNOTTY */
 #endif

util.c

@@ -291,7 +291,7 @@ int copy_file(char *source, char *dest, mode_t mode)
 	}
 
 	ofd = do_open(dest, O_WRONLY | O_CREAT | O_TRUNC | O_EXCL, mode);
-	if (ofd < 0) {
+	if (ofd == -1) {
 		rprintf(FERROR,"open %s: %s\n",
 			dest,strerror(errno));
 		close(ifd);