pid_from_ns_wrapper: remove the loop

If we clone a child which can't reply to us within the timeout, do
not keep looping, just return an error.  Commonize the function
superficially to make it look like pid_to_ns_wrapper().  Presumably
we can now merge these into one function, that's left for later.

Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>

diff --git a/bindings.c b/bindings.c
index f9dc7627f54b04c8925aa0c21e83c8e0a018a2ae..25a578228e112764743f412e3fc6f41168ad1113 100644 (file)
--- a/bindings.c
+++ b/bindings.c
@@ -2238,8 +2238,6 @@ static void pid_from_ns_wrapper(int sock, pid_t tpid)
        char fnam[100];
        pid_t cpid;
        char v;
-       size_t stack_size = sysconf(_SC_PAGESIZE);
-       void *stack;
 
        ret = snprintf(fnam, sizeof(fnam), "/proc/%d/ns/pid", tpid);
        if (ret < 0 || ret >= sizeof(fnam))
@@ -2260,32 +2258,24 @@ static void pid_from_ns_wrapper(int sock, pid_t tpid)
                .tpid = tpid,
                .wrapped = &pid_from_ns
        };
-
-loop:
-       stack = alloca(stack_size);
+       size_t stack_size = sysconf(_SC_PAGESIZE);
+       void *stack = alloca(stack_size);
 
        cpid = clone(pid_ns_clone_wrapper, stack + stack_size, SIGCHLD, &args);
-
        if (cpid < 0)
                _exit(1);
 
        // give the child 1 second to be done forking and
        // write its ack
        if (!wait_for_sock(cpipe[0], 1))
-               goto again;
+               _exit(1);
        ret = read(cpipe[0], &v, 1);
-       if (ret != sizeof(char) || v != '1') {
-               goto again;
-       }
+       if (ret != sizeof(char) || v != '1')
+               _exit(1);
 
        if (!wait_for_pid(cpid))
                _exit(1);
        _exit(0);
-
-again:
-       kill(cpid, SIGKILL);
-       wait_for_pid(cpid);
-       goto loop;
 }
 
 /*