[GXemul-devel] Patch: Fix console data loss due to interrupted writes

[Andreas G. <gs...@gs...>]

Hi,

The NetBSD project runs automated tests of NetBSD/pmax and
NetBSD/hpcmips hosted on gxemul virtual machines:

  http://releng.netbsd.org/b5reports/pmax/
  http://releng.netbsd.org/b5reports/hpcmips/
  
The installation step of the tests has been randomly failing, and I
have now tracked down the cause: parts of the gxemul console output
are sometimes lost because write() system calls writing the console
output to stdout are interrupted by SIGALRM.  The following patch
appears to fix the problem.

--- src/old_main/timer.cc.orig	2018-12-07 06:29:22.000000000 +0000
+++ src/old_main/timer.cc
@@ -229,6 +229,7 @@ void timer_start(void)
 
 	memset(&saction, 0, sizeof(saction));
 	saction.sa_handler = timer_tick;
+	saction.sa_flags = SA_RESTART;
 
 	sigaction(SIGALRM, &saction, NULL);