X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=arch%2Fum%2Fkernel%2Fhelper.c;h=13b1f5c2f7ee3018c407b06ea851da1108af04d1;hb=6a77f38946aaee1cd85eeec6cf4229b204c15071;hp=0e3d409d9b3f6771380374eaa61e99960c3e6ff7;hpb=87fc8d1bb10cd459024a742c6a10961fefcef18f;p=linux-2.6.git

diff --git a/arch/um/kernel/helper.c b/arch/um/kernel/helper.c
index 0e3d409d9..13b1f5c2f 100644
--- 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);
 }