vserver 1.9.5.x5

[linux-2.6.git] / arch / um / kernel / helper.c

diff --git a/arch/um/kernel/helper.c b/arch/um/kernel/helper.c
index 0e3d409..13b1f5c 100644 (file)
--- a/arch/um/kernel/helper.c
+++ b/arch/um/kernel/helper.c
@@ -49,14 +49,14 @@ static int helper_child(void *arg)
        return(0);
 }
 
-/* XXX The alloc_stack here breaks if this is called in the tracing thread */
-
+/* Returns either the pid of the child process we run or -E* on failure.
+ * XXX The alloc_stack here breaks if this is called in the tracing thread */
 int run_helper(void (*pre_exec)(void *), void *pre_data, char **argv,
               unsigned long *stack_out)
 {
        struct helper_data data;
        unsigned long stack, sp;
-       int pid, fds[2], err, n;
+       int pid, fds[2], ret, n;
 
        if((stack_out != NULL) && (*stack_out != 0))
                stack = *stack_out;
@@ -64,16 +64,16 @@ int run_helper(void (*pre_exec)(void *), void *pre_data, char **argv,
        if(stack == 0)
                return(-ENOMEM);
 
-       err = os_pipe(fds, 1, 0);
-       if(err < 0){
-               printk("run_helper : pipe failed, err = %d\n", -err);
+       ret = os_pipe(fds, 1, 0);
+       if(ret < 0){
+               printk("run_helper : pipe failed, ret = %d\n", -ret);
                goto out_free;
        }
 
-       err = os_set_exec_close(fds[1], 1);
-       if(err < 0){
-               printk("run_helper : setting FD_CLOEXEC failed, err = %d\n",
-                      -err);
+       ret = os_set_exec_close(fds[1], 1);
+       if(ret < 0){
+               printk("run_helper : setting FD_CLOEXEC failed, ret = %d\n",
+                      -ret);
                goto out_close;
        }
 
@@ -85,34 +85,36 @@ int run_helper(void (*pre_exec)(void *), void *pre_data, char **argv,
        pid = clone(helper_child, (void *) sp, CLONE_VM | SIGCHLD, &data);
        if(pid < 0){
                printk("run_helper : clone failed, errno = %d\n", errno);
-               err = -errno;
+               ret = -errno;
                goto out_close;
        }
 
        os_close_file(fds[1]);
-       n = os_read_file(fds[0], &err, sizeof(err));
+       fds[1] = -1;
+
+       /*Read the errno value from the child.*/
+       n = os_read_file(fds[0], &ret, sizeof(ret));
        if(n < 0){
-               printk("run_helper : read on pipe failed, err = %d\n", -n);
-               err = n;
-               goto out_kill;
+               printk("run_helper : read on pipe failed, ret = %d\n", -n);
+               ret = n;
+               os_kill_process(pid, 1);
        }
        else if(n != 0){
                CATCH_EINTR(n = waitpid(pid, NULL, 0));
-               pid = -errno;
+               ret = -errno;
+       } else {
+               ret = pid;
        }
 
-       if(stack_out == NULL) free_stack(stack, 0);
-        else *stack_out = stack;
-       return(pid);
-
- out_kill:
-       os_kill_process(pid, 1);
- out_close:
+out_close:
+       if (fds[1] != -1)
+               os_close_file(fds[1]);
        os_close_file(fds[0]);
-       os_close_file(fds[1]);
- out_free:
-       free_stack(stack, 0);
-       return(err);
+out_free:
+       if(stack_out == NULL)
+               free_stack(stack, 0);
+       else *stack_out = stack;
+       return(ret);
 }
 
 int run_helper_thread(int (*proc)(void *), void *arg, unsigned int flags, 
@@ -143,7 +145,7 @@ int run_helper_thread(int (*proc)(void *), void *arg, unsigned int flags,
                               "0x%x\n", status);
                free_stack(stack, stack_order);
        }
-        else *stack_out = stack;
+       else *stack_out = stack;
        return(pid);
 }