[PATCH v10 01/25] tools/xenstore: switch barf[_perror]() to use syslog()

[Juergen Gross <jgross@xxxxxxxx>]

When xenstored crashes due to an unrecoverable condition it is calling
either barf() or barf_perror() to issue a message and then exit().

Make sure the message is visible somewhere by using syslog()
additionally to xprintf(), as the latter will be visible only with
tracing active.

Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Reviewed-by: Paul Durrant <paul@xxxxxxx>
Reviewed-by: Julien Grall <jgrall@xxxxxxxxxx>
---
V4:
- new patch
---
 tools/xenstore/utils.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/tools/xenstore/utils.c b/tools/xenstore/utils.c
index a1ac12584a..633ce3b4fc 100644
--- a/tools/xenstore/utils.c
+++ b/tools/xenstore/utils.c
@@ -3,6 +3,7 @@
 #include <stdarg.h>
 #include <stdlib.h>
 #include <string.h>
+#include <syslog.h>
 #include <errno.h>
 #include <unistd.h>
 #include <fcntl.h>
@@ -35,6 +36,7 @@ void barf(const char *fmt, ...)
        va_end(arglist);
 
        if (bytes >= 0) {
+               syslog(LOG_CRIT, "%s\n", str);
                xprintf("%s\n", str);
                free(str);
        }
@@ -54,6 +56,7 @@ void barf_perror(const char *fmt, ...)
        va_end(arglist);
 
        if (bytes >= 0) {
+               syslog(LOG_CRIT, "%s: %s\n", str, strerror(err));
                xprintf("%s: %s\n", str, strerror(err));
                free(str);
        }
-- 
2.26.2