[Libvirt-cim] [PATCH] Redirect stdout & stderr when run as out-of-process provider

[Chip Vincent]

# HG changeset patch
# User Chip Vincent <cvincent at us.ibm.com>
# Date 1316557881 14400
# Node ID 4d95f2e9f2d8eac1565307def96bd158f5dcf160
# Parent  db809376d763493849c2a19f587969eaec619b75
Redirect stdout & stderr when run as out-of-process provider

When a provider is loaded in-process by Pegasus, messages sent to
stdout and stderr are suppressed. However, when loaded out-of-process,
those same messages appear on the console. This happens excessively when
libvirt-cim LXC_ and XEN_ classes are enumerated and libvirt sends
"libvir: error : no connection driver available for..." messages to stderr.
In development, this can sometimes prevent console usage. Until a fix is
made to Pegasus, we'll suppress console output during provider initialization
when run in out-of-process mode.

Signed-off-by: Chip Vincent <cvincent at us.ibm.com>

diff --git a/libxkutil/misc_util.c b/libxkutil/misc_util.c
--- a/libxkutil/misc_util.c
+++ b/libxkutil/misc_util.c
@@ -29,6 +29,7 @@
 #include <stdarg.h>
 #include <unistd.h>
 #include <pthread.h>
+#include <errno.h>
 #include <libvirt/libvirt.h>
 #include <libvirt/virterror.h>
 
@@ -540,6 +541,17 @@
 {
         int ret = 0;
 
+        /* The tog-pegasus out-of-process provider feature does not
+        * redirect stdout and stderr, so it's done here to prevent
+        * any messages from taking over the console. One example is
+        * verbose connection failures sent to stdout by libvirt. */
+        if (strstr(program_invocation_short_name, "cimprovagt") != NULL) {
+                CU_DEBUG("Redirecting stdout and stderr");
+
+                stdout = freopen("/dev/null", "a", stdout);
+                stderr = freopen("/dev/null", "a", stderr);
+        }
+
         /* double-check lock pattern used for performance reasons */
         if (libvirt_initialized == 0) {
                 pthread_mutex_lock(&libvirt_mutex);