Changeset 1c635d6 in mainline for uspace/lib/c/include/task.h

Timestamp:

2014-08-26T15:12:12Z (11 years ago)

Author:

Martin Sucha <sucha14@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

613d644

Parents:

df7f5cea

Message:

Do not hold a task's return value after it has disconnected.

Holding the task's return value meant that if nobody waited
for task's result, it polluted NS's memory. This was apparently
done because of a race between spawning a task and waiting for it.

We solve this problem in another way: ns discards the return value
as soon as the task disconnects from it. This typically happens
when the task finishes its execution. In order to avoid the race,
we send the wait request to ns while spawning the task (i.e. when
we talk to the loader), but before we allow the loaded program
to run.

Fixes #132

File:

• uspace/lib/c/include/task.h (modified) (2 diffs)

uspace/lib/c/include/task.h

@@ -39 +39 @@
 #include <abi/proc/task.h>
 #include <stdarg.h>
+#include <async.h>
+#include <types/task.h>
 
-typedef enum {
-        TASK_EXIT_NORMAL,
-        TASK_EXIT_UNEXPECTED
-} task_exit_t;
+typedef struct {
+        ipc_call_t result;
+        aid_t aid;
+} task_wait_t;
+
+struct _TASK;
+typedef struct _TASK task_t;
 
 extern task_id_t task_get_id(void);
@@ -49 +54 @@
 extern int task_kill(task_id_t);
 
-extern int task_spawnv(task_id_t *, const char *path, const char *const []);
-extern int task_spawnvf(task_id_t *, const char *path, const char *const [],
-    int *const []);
-extern int task_spawn(task_id_t *, const char *path, int, va_list ap);
-extern int task_spawnl(task_id_t *, const char *path, ...);
+extern int task_spawnv(task_id_t *, task_wait_t *, const char *path,
+    const char *const []);
+extern int task_spawnvf(task_id_t *, task_wait_t *, const char *path,
+    const char *const [], int *const []);
+extern int task_spawn(task_id_t *, task_wait_t *, const char *path, int,
+    va_list ap);
+extern int task_spawnl(task_id_t *, task_wait_t *, const char *path, ...);
 
-extern int task_wait(task_id_t id, task_exit_t *, int *);
+extern int task_setup_wait(task_id_t, task_wait_t *);
+extern void task_cancel_wait(task_wait_t *);
+extern int task_wait(task_wait_t *, task_exit_t *, int *);
+extern int task_wait_task_id(task_id_t, task_exit_t *, int *);
 extern int task_retval(int);