From 95592b47be09bd9347026ff9aa298fc097733e56 Mon Sep 17 00:00:00 2001 From: JunweiZhang Date: Tue, 9 Jul 2013 08:55:20 -0700 Subject: [PATCH] ipbatch: fix use of 'ip netns exec' execvp() does not return when the command succeed, hence all commands in the batch file after the line 'ip netns exec' are not executed. Let's fork before calling execvp() if batch mode is used.. Example: $ cat test.batch netns add netns1 netns exec netns1 ip l netns $ ip -b test.batch 1: lo: mtu 65536 qdisc noop state DOWN mode DEFAULT link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 2: sit0: mtu 1480 qdisc noop state DOWN mode DEFAULT link/sit 0.0.0.0 brd 0.0.0.0 All command after 'netns exec' are never executed. With the patch: $ ip -b test.batch 1: lo: mtu 65536 qdisc noop state DOWN mode DEFAULT link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 2: sit0: mtu 1480 qdisc noop state DOWN mode DEFAULT link/sit 0.0.0.0 brd 0.0.0.0 netns1 Now, existing netns are displayed. Signed-off-by: JunweiZhang Signed-off-by: Nicolas Dichtel --- ip/ipnetns.c | 34 +++++++++++++++++++++++++++++++++- 1 file changed, 33 insertions(+), 1 deletion(-) diff --git a/ip/ipnetns.c b/ip/ipnetns.c index fa2b6810..d534fb69 100644 --- a/ip/ipnetns.c +++ b/ip/ipnetns.c @@ -42,6 +42,7 @@ #define MS_SHARED (1 << 20) #endif +extern char *batch_file; #ifndef HAVE_SETNS static int setns(int fd, int nstype) @@ -185,10 +186,41 @@ static int netns_exec(int argc, char **argv) /* Setup bind mounts for config files in /etc */ bind_etc(name); + fflush(stdout); + + if (batch_file) { + int status; + pid_t pid; + + pid = fork(); + if (pid < 0) { + perror("fork"); + return EXIT_FAILURE; + } + + if (pid != 0) { + /* Parent */ + if (waitpid(pid, &status, 0) < 0) { + perror("waitpid"); + return EXIT_FAILURE; + } + + if (WIFEXITED(status)) { + /* ip must returns the status of the child, + * but do_cmd() will add a minus to this, + * so let's add another one here to cancel it. + */ + return -WEXITSTATUS(status); + } + + return EXIT_FAILURE; + } + } + if (execvp(cmd, argv + 1) < 0) fprintf(stderr, "exec of \"%s\" failed: %s\n", cmd, strerror(errno)); - return EXIT_FAILURE; + _exit(EXIT_FAILURE); } static int is_pid(const char *str)