[CRIU] [PATCH] page-server: allow to execute page-server in the background

[Andrey Vagin]

page-server creates a listen socket and only then goes into the
background, so we can be sure, that page-server is ready for work after
detaching.

Signed-off-by: Andrey Vagin <avagin at openvz.org>
---
 crtools.c           | 8 +++++++-
 include/page-xfer.h | 2 +-
 page-xfer.c         | 5 ++++-
 test/zdtm.sh        | 2 +-
 4 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/crtools.c b/crtools.c
index 769cade..07138a6 100644
--- a/crtools.c
+++ b/crtools.c
@@ -67,6 +67,7 @@ int main(int argc, char *argv[])
 	int opt, idx;
 	int log_inited = 0;
 	int log_level = 0;
+	bool daemon_mode = false;
 
 	BUILD_BUG_ON(PAGE_SIZE != PAGE_IMAGE_SIZE);
 
@@ -116,6 +117,7 @@ int main(int argc, char *argv[])
 			{ "prev-images-dir", required_argument, 0, 53},
 			{ "ms", no_argument, 0, 54},
 			{ "track-mem", no_argument, 0, 55},
+			{ "daemon", no_argument, 0, 56},
 			{ },
 		};
 
@@ -271,6 +273,9 @@ int main(int argc, char *argv[])
 		case 54:
 			opts.check_ms_kernel = true;
 			break;
+		case 56:
+			daemon_mode = true;
+			break;
 		case 'V':
 			pr_msg("Version: %s\n", version);
 			return 0;
@@ -346,7 +351,7 @@ int main(int argc, char *argv[])
 	}
 
 	if (!strcmp(argv[optind], "page-server"))
-		return  cr_page_server();
+		return cr_page_server(daemon_mode);
 
 	pr_msg("Unknown command \"%s\"\n", argv[optind]);
 usage:
@@ -415,6 +420,7 @@ usage:
 "Page server options\n"
 "  --address ADDR        address of page server\n"
 "  --port PORT           port of page server\n"
+"  --daemon              run in the background\n"
 "\n"
 "Show options:\n"
 "  -f|--file FILE        show contents of a checkpoint file\n"
diff --git a/include/page-xfer.h b/include/page-xfer.h
index a6960c1..67a59ec 100644
--- a/include/page-xfer.h
+++ b/include/page-xfer.h
@@ -1,6 +1,6 @@
 #ifndef __CR_PAGE_XFER__H__
 #define __CR_PAGE_XFER__H__
-int cr_page_server(void);
+int cr_page_server(bool daemon_mode);
 
 /*
  * page_xfer -- transfer pages into image file.
diff --git a/page-xfer.c b/page-xfer.c
index 8864e94..7a93068 100644
--- a/page-xfer.c
+++ b/page-xfer.c
@@ -195,7 +195,7 @@ static int page_server_serve(int sk)
 	return ret;
 }
 
-int cr_page_server(void)
+int cr_page_server(bool daemon_mode)
 {
 	int sk, ask = -1;
 	struct sockaddr_in caddr;
@@ -233,6 +233,9 @@ out:
 	if (ask < 0)
 		return -1;
 
+	if (daemon_mode)
+		daemon(0, 0);
+
 	pr_info("Accepted connection from %s:%u\n",
 			inet_ntoa(caddr.sin_addr),
 			(int)ntohs(caddr.sin_port));
diff --git a/test/zdtm.sh b/test/zdtm.sh
index ace17b6..a82bf97 100755
--- a/test/zdtm.sh
+++ b/test/zdtm.sh
@@ -349,7 +349,7 @@ EOF
 	mkdir -p $ddump
 
 	if [ $PAGE_SERVER -eq 1 ]; then
-		$CRTOOLS page-server -D $ddump -o page_server.log -v 4 --port $PS_PORT &
+		$CRTOOLS page-server -D $ddump -o page_server.log -v 4 --port $PS_PORT
 		PS_PID=$!
 		opts="--page-server --address 127.0.0.1 --port $PS_PORT"
 	fi
-- 
1.8.2