diff options
Diffstat (limited to 'include/qemu')
-rw-r--r-- | include/qemu/lockable.h | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/include/qemu/lockable.h b/include/qemu/lockable.h index 313d4d9b73..90342bab98 100644 --- a/include/qemu/lockable.h +++ b/include/qemu/lockable.h @@ -106,4 +106,69 @@ static inline void qemu_lockable_unlock(QemuLockable *x) x->unlock(x->object); } +static inline QemuLockable *qemu_lockable_auto_lock(QemuLockable *x) +{ + qemu_lockable_lock(x); + return x; +} + +static inline void qemu_lockable_auto_unlock(QemuLockable *x) +{ + if (x) { + qemu_lockable_unlock(x); + } +} + +G_DEFINE_AUTOPTR_CLEANUP_FUNC(QemuLockable, qemu_lockable_auto_unlock) + +#define WITH_QEMU_LOCK_GUARD_(x, var) \ + for (g_autoptr(QemuLockable) var = \ + qemu_lockable_auto_lock(QEMU_MAKE_LOCKABLE_NONNULL((x))); \ + var; \ + qemu_lockable_auto_unlock(var), var = NULL) + +/** + * WITH_QEMU_LOCK_GUARD - Lock a lock object for scope + * + * @x: a lock object (currently one of QemuMutex, CoMutex, QemuSpin). + * + * This macro defines a lock scope such that entering the scope takes the lock + * and leaving the scope releases the lock. Return statements are allowed + * within the scope and release the lock. Break and continue statements leave + * the scope early and release the lock. + * + * WITH_QEMU_LOCK_GUARD(&mutex) { + * ... + * if (error) { + * return; <-- mutex is automatically unlocked + * } + * + * if (early_exit) { + * break; <-- leave this scope early + * } + * ... + * } + */ +#define WITH_QEMU_LOCK_GUARD(x) \ + WITH_QEMU_LOCK_GUARD_((x), qemu_lockable_auto##__COUNTER__) + +/** + * QEMU_LOCK_GUARD - Lock an object until the end of the scope + * + * @x: a lock object (currently one of QemuMutex, CoMutex, QemuSpin). + * + * This macro takes a lock until the end of the scope. Return statements + * release the lock. + * + * ... <-- mutex not locked + * QEMU_LOCK_GUARD(&mutex); <-- mutex locked from here onwards + * ... + * if (error) { + * return; <-- mutex is automatically unlocked + * } + */ +#define QEMU_LOCK_GUARD(x) \ + g_autoptr(QemuLockable) qemu_lockable_auto##__COUNTER__ = \ + qemu_lockable_auto_lock(QEMU_MAKE_LOCKABLE((x))) + #endif |