bridge: Allow to easy change network namespace

Added new '-netns' option to simplify executing following cmd:

    ip netns exec NETNS bridge OPTIONS COMMAND OBJECT

    to

    bridge -n[etns] NETNS OPTIONS COMMAND OBJECT

e.g.:

    bridge -net vnet0 fdb
Signed-off-by: Vadim Kochan <vadim4j@gmail.com>
Signed-off-by: Jiri Pirko <jiri@resnulli.us>

bridge/Makefile

@@ -2,6 +2,10 @@ BROBJ = bridge.o fdb.o monitor.o link.o mdb.o vlan.o
 
 include ../Config
 
+ifeq ($(IP_CONFIG_SETNS),y)
+	CFLAGS += -DHAVE_SETNS
+endif
+
 all: bridge
 
 bridge: $(BROBJ) $(LIBNETLINK) 

bridge/bridge.c

@@ -13,6 +13,7 @@
 #include "SNAPSHOT.h"
 #include "utils.h"
 #include "br_common.h"
+#include "namespace.h"
 
 struct rtnl_handle rth = { .fd = -1 };
 int preferred_family = AF_UNSPEC;
@@ -31,7 +32,7 @@ static void usage(void)
 "Usage: bridge [ OPTIONS ] OBJECT { COMMAND | help }\n"
 "where  OBJECT := { link | fdb | mdb | vlan | monitor }\n"
 "       OPTIONS := { -V[ersion] | -s[tatistics] | -d[etails] |\n"
-"                    -o[neline] | -t[imestamp] \n");
+"                    -o[neline] | -t[imestamp] | -n[etns] name }\n");
 	exit(-1);
 }
 
@@ -112,6 +113,10 @@ main(int argc, char **argv)
 			preferred_family = AF_INET;
 		} else if (strcmp(opt, "-6") == 0) {
 			preferred_family = AF_INET6;
+		} else if (matches(opt, "-netns") == 0) {
+			NEXT_ARG();
+			if (netns_switch(argv[1]))
+				exit(-1);
 		} else {
 			fprintf(stderr, "Option \"%s\" is unknown, try \"bridge help\".\n", opt);
 			exit(-1);

man/man8/bridge.8

@@ -19,7 +19,8 @@ bridge \- show / manipulate bridge addresses and devices
 .ti -8
 .IR OPTIONS " := { "
 \fB\-V\fR[\fIersion\fR] |
-\fB\-s\fR[\fItatistics\fR] }
+\fB\-s\fR[\fItatistics\fR] |
+\fB\-n\fR[\fIetns\fR] name }
 
 .ti -8
 .BR "bridge link set"
@@ -112,6 +113,26 @@ output more information.  If this option
 is given multiple times, the amount of information increases.
 As a rule, the information is statistics or some time values.
 
+.TP
+.BR "\-n" , " \-net" , " \-netns " <NETNS>
+switches
+.B bridge
+to the specified network namespace
+.IR NETNS .
+Actually it just simplifies executing of:
+
+.B ip netns exec
+.IR NETNS
+.B bridge
+.RI "[ " OPTIONS " ] " OBJECT " { " COMMAND " | "
+.BR help " }"
+
+to
+
+.B bridge
+.RI "-n[etns] " NETNS " [ " OPTIONS " ] " OBJECT " { " COMMAND " | "
+.BR help " }"
+
 
 .SH BRIDGE - COMMAND SYNTAX