From: Michal Privoznik <mpriv...@redhat.com>
As promised in previous commit, make NSS modules silent by
default and enable debug printings if LIBVIRT_NSS_DEBUG envvar is
set.
Signed-off-by: Michal Privoznik <mpriv...@redhat.com>
---
docs/nss.rst | 13 +++++++++++++
tools/nss/libvirt_nss_log.c | 4 ++++
tools/nss/libvirt_nss_log.h | 2 ++
3 files changed, 19 insertions(+)
diff --git a/docs/nss.rst b/docs/nss.rst
index be137d987b..3df85cee0a 100644
--- a/docs/nss.rst
+++ b/docs/nss.rst
@@ -111,6 +111,19 @@ their IP addresses in any other way (usermode networking,
assigned network
devices and so on) will not be able to have their hostnames resolved through
it.
+Debugging
+---------
+
+:since:`Since 11.5.0` both NSS modules check for ``LIBVIRT_NSS_DEBUG``
+environment variable¸ which if set to any value turns on printing of debug and
+error messages onto standard error output. This can be useful when debugging
+either of the module.
+
+::
+
+ $ LIBVIRT_NSS_DEBUG=1 getent hosts mydomain
+
+
Alternatives
------------
diff --git a/tools/nss/libvirt_nss_log.c b/tools/nss/libvirt_nss_log.c
index 0863897c07..9a28a91800 100644
--- a/tools/nss/libvirt_nss_log.c
+++ b/tools/nss/libvirt_nss_log.c
@@ -24,6 +24,7 @@
#include <stdio.h>
#include <string.h>
#include <stdarg.h>
+#include <stdlib.h>
#include "libvirt_nss_log.h"
#include "libvirt_nss.h"
@@ -54,6 +55,9 @@ nssLog(nssLogPriority prio,
g_autofree char *ebuf = NULL;
va_list ap;
+ if (!getenv(NSS_LOG_ENV_VAR))
+ return;
+
fprintf(stderr, "%s %s:%d : ", nssLogPriorityToString(prio), func, linenr);
va_start(ap, fmt);
diff --git a/tools/nss/libvirt_nss_log.h b/tools/nss/libvirt_nss_log.h
index bac64d4bc7..25926fb6de 100644
--- a/tools/nss/libvirt_nss_log.h
+++ b/tools/nss/libvirt_nss_log.h
@@ -31,6 +31,8 @@ typedef enum {
#define ERROR(...) \
nssLog(NSS_ERROR, __FUNCTION__, __LINE__, __VA_ARGS__)
+#define NSS_LOG_ENV_VAR "LIBVIRT_NSS_DEBUG"
+
void
nssLog(nssLogPriority prio,
const char *func,
--
2.49.0
