clusterd: Add checks for write errors

Currently we may move received files in place, even whe the write or
close were unsuccessfull (eg. disk full). This is a serious bug and we
may end up with an empty passwd.

Add checks for all write() and close() calls.
Also log rename errors.

clusterd/clusterd

@@ -895,12 +895,12 @@ sub udp_rx_filedata {
 		# complete file in one broadcast
 		my $fh=IO::File->new($tmp_filename,O_WRONLY|O_CREAT,0);
 		defined $fh or return warn "$tmp_filename: $!\n";
-		$fh->syswrite($data);
-		$fh->close;
+		$fh->syswrite($data) or return warn "$tmp_filename: $!\n";
+		$fh->close or return warn "$tmp_filename: $!\n";
 		chown $st_want->uid,$st_want->gid,$tmp_filename or return warn "$tmp_filename: $!\n";
 		chmod $st_want->perm,$tmp_filename or return warn "$tmp_filename: $!\n";
 		$st_is and unlink($filename);
-		rename($tmp_filename,$filename);
+		rename($tmp_filename,$filename) or return warn "rename $tmp_filename $filename: $!\n";
 		utime($st_want->mtime,$st_want->mtime,$filename);
 		warn "installed $filename\n";
 		$rx_filedata_done=1;
@@ -945,7 +945,7 @@ sub udp_rx_filedata {
 			chown $st_want->uid,$st_want->gid,$tmp_filename or return warn "$tmp_filename: $!\n";
 			chmod $st_want->perm,$tmp_filename or return warn "$tmp_filename: $!\n";
 			$st_is and unlink($filename);
-			rename($tmp_filename,$filename);
+			rename($tmp_filename,$filename) or return warn "rename $tmp_filename $filename: $!\n";
 			utime($st_want->mtime,$st_want->mtime,$filename);
 			warn "installed $filename\n";
 			delete $RECEIVER{$filename};
@@ -1753,10 +1753,10 @@ sub udp_rx_push {
 	if ($st_want->size==0) {
 		my $fh=IO::File->new($tmp_filename,O_WRONLY|O_CREAT,0);
 		defined $fh or return warn "$tmp_filename: $!\n";
-		$fh->close;
+		$fh->close or return warn "$tmp_filename: $!\n";
 		chown $st_want->uid,$st_want->gid,$tmp_filename or return warn "$tmp_filename: $!\n";
 		chmod $st_want->perm,$tmp_filename or return warn "$tmp_filename: $!\n";
-		rename($tmp_filename,$filename);
+		rename($tmp_filename,$filename) or return warn "rename $tmp_filename $filename: $!\n";;
 		utime($st_want->mtime,$st_want->mtime,$filename);
 		warn "installed (empty) $filename\n";
 		return;
@@ -1777,17 +1777,17 @@ sub udp_rx_push {
 				my ($buf)=@_;
 				if ($!) { warn "$ip: $!\n";$cb=undef;return; }
 				if (length($buf)==0) { warn "$ip: EOF\n";$cb=undef;return;}
-				print $fh $buf;
+				print $fh $buf or return warn "$tmp_filename: $!\n";
 				$bytes-=length($buf);
 				if ($bytes>0) {
 					My::Select::INET::read_with_timeout($s,$cb,$TCP_TIMEOUT);
 					return;
 				}
 				$cb=undef;
-				close $fh;
+				close $fh or return warn "$tmp_filename: $!\n";
 				chown $st_want->uid,$st_want->gid,$tmp_filename or return warn "$tmp_filename: $!\n";
 				chmod $st_want->perm,$tmp_filename or return warn "$tmp_filename: $!\n";
-				rename($tmp_filename,$filename) or return warn "$filename: $!\n";
+				rename($tmp_filename,$filename) or return warn "rename $tmp_filename $filename: $!\n";
 				utime($st_want->mtime,$st_want->mtime,$filename);
 				warn "installed $filename\n";
 			};