Merge remote-tracking branch 'origin/pr/63'

* origin/pr/63:
  qrexec: hide timing debug messages in vm-file-editor
  qrexec: write service stderr to both syslog and caller

qrexec/qubes-rpc-multiplexer

@@ -1,9 +1,18 @@
 #!/bin/sh
 
-mkfifo /tmp/qrexec-rpc-stderr.$$
-logger -t "$1-$2" -f /tmp/qrexec-rpc-stderr.$$ >/dev/null 2>&1 </dev/null &
-exec 2>/tmp/qrexec-rpc-stderr.$$
-rm -f /tmp/qrexec-rpc-stderr.$$
+# write stderr to both calling party and local log; be very careful about
+# closing file descriptors here - if either stdout or stderr will not be closed
+# when service process does the same - service call will hang (waiting for EOF
+# on stdout/stderr)
+stderr_pipe=/tmp/qrexec-rpc-stderr.$$
+mkfifo $stderr_pipe
+# tee can't write to file descriptor, nor /proc/self/fd/2 (EXIO on open)
+return_stderr_pipe=/tmp/qrexec-rpc-stderr-return.$$
+mkfifo $return_stderr_pipe
+{ cat <$return_stderr_pipe >&2 2>/dev/null; rm -f $return_stderr_pipe; } &
+{ tee $return_stderr_pipe 2>/dev/null <$stderr_pipe |\
+       logger -t "$1-$2" >/dev/null 2>&1; rm -f $stderr_pipe; } &
+exec 2>$stderr_pipe
 
 QUBES_RPC=/etc/qubes-rpc
 LOCAL_QUBES_RPC=/usr/local/etc/qubes-rpc

qubes-rpc/vm-file-editor.c

@@ -12,6 +12,7 @@
 
 #define USER_HOME "/home/user"
 #define TMP_LOC "/tmp/qopen/"
+// #define DEBUG
 
 static const char *cleanup_filename = NULL;
 
@@ -154,7 +155,9 @@ main()
 		perror("stat pre");
 		exit(1);
 	}
+#ifdef DEBUG
 	fprintf(stderr, "time=%s, waiting for qubes-session\n", gettime());
+#endif
 	// wait for X server to starts (especially in DispVM)
 	if (stat("/tmp/qubes-session-env", &session_stat)) {
 		switch (child = fork()) {
@@ -183,7 +186,9 @@ main()
 				}
 		}
 	}
+#ifdef DEBUG
 	fprintf(stderr, "time=%s, starting editor\n", gettime());
+#endif
 	switch (child = fork()) {
 		case -1:
 			perror("fork");