[PATCH 13/19] Add fuse_session_set_debug() to enable debug output without foreground

[Bernd Schubert <bernd@bsbernd.com>]

From: Bernd Schubert <bschubert@ddn.com>

One might want to print debug out in background mode, which the command
line parameter does not easily allow. Or one might want to enable and
disable at run time.

Signed-off-by: Bernd Schubert <bschubert@ddn.com>
---
 include/fuse_lowlevel.h | 12 ++++++++++++
 lib/fuse_lowlevel.c     |  5 +++++
 lib/fuse_versionscript  |  1 +
 3 files changed, 18 insertions(+)

diff --git a/include/fuse_lowlevel.h b/include/fuse_lowlevel.h
index d8626f85bdaf497534cd2835a589e30f1f4e2466..d85929e291a77de8caad7d6b3d9ac5b092ce0e62 100644
--- a/include/fuse_lowlevel.h
+++ b/include/fuse_lowlevel.h
@@ -2441,6 +2441,18 @@ int fuse_session_receive_buf(struct fuse_session *se, struct fuse_buf *buf);
  */
 void fuse_session_want_sync_init(struct fuse_session *se);
 
+/**
+ * Enable debug output
+ *
+ * This allows to enable debug output without a command line parameter and
+ * without the enforcement of the command line parameter to run in foreground.
+ * The daemon needs to handle either fuse_log output via stderr, or
+ * redirection to its own logs or via syslog.
+ *
+ * @param se the session
+ */
+void fuse_session_set_debug(struct fuse_session *se);
+
 /**
  * Check if the request is submitted through fuse-io-uring
  */
diff --git a/lib/fuse_lowlevel.c b/lib/fuse_lowlevel.c
index b10def03f3666757d312f87f177a560483691d6f..a7293a3898c37c3877eadf965d310ae2aa5cc2d1 100644
--- a/lib/fuse_lowlevel.c
+++ b/lib/fuse_lowlevel.c
@@ -5007,3 +5007,8 @@ void fuse_session_want_sync_init(struct fuse_session *se)
 		return;
 	se->want_sync_init = true;
 }
+
+void fuse_session_set_debug(struct fuse_session *se)
+{
+	se->debug = 1;
+}
diff --git a/lib/fuse_versionscript b/lib/fuse_versionscript
index f1765d39e13bc9b1f53e625b9a091c5fa53f5afd..64bf75ac2cb252d066ac301be8fc024b59f903ac 100644
--- a/lib/fuse_versionscript
+++ b/lib/fuse_versionscript
@@ -230,6 +230,7 @@ FUSE_3.19 {
 		fuse_daemonize_start;
 		fuse_daemonize_signal;
 		fuse_daemonize_active;
+		fuse_session_set_debug;
 } FUSE_3.18;
 
 # Local Variables:

-- 
2.43.0