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1 #include "pthread_impl.h"
2 
3 // Set a recursive lock to init status, memory is "01 00 ... 00"
__pthread_mutex_unlock_recursive_inner(pthread_mutex_t * m)4 void __pthread_mutex_unlock_recursive_inner(pthread_mutex_t *m)
5 {
6 	char *p = (char *)m;
7 	for (size_t i = 0;i < sizeof(pthread_mutex_t);i++) {
8 		*(p + i) = 0;
9 	}
10 	m->_m_type = PTHREAD_MUTEX_RECURSIVE; // Set recursive flag
11 }
12 
__pthread_mutex_unlock(pthread_mutex_t * m)13 int __pthread_mutex_unlock(pthread_mutex_t *m)
14 {
15 	pthread_t self;
16 	int waiters = m->_m_waiters;
17 	int cont;
18 	int type = m->_m_type & 15;
19 	int priv = (m->_m_type & 128) ^ 128;
20 	int new = 0;
21 	int old;
22 
23 	if (type != PTHREAD_MUTEX_NORMAL) {
24 		self = __pthread_self();
25 		old = m->_m_lock;
26 		int own = old & 0x3fffffff;
27 		if (own != self->tid)
28 			return EPERM;
29 #ifdef __LITEOS_A__
30 		if ((type & PTHREAD_MUTEX_TYPE_MASK) == PTHREAD_MUTEX_RECURSIVE && m->_m_count)
31 #else
32 		if (__is_mutex_destroyed(m->_m_type))
33 			__handle_using_destroyed_mutex(m, __FUNCTION__);
34 		if ((type&3) == PTHREAD_MUTEX_RECURSIVE && m->_m_count)
35 #endif
36 			return m->_m_count--, 0;
37 		if ((type&4) && (old&0x40000000))
38 			new = 0x7fffffff;
39 		if (!priv) {
40 			self->robust_list.pending = &m->_m_next;
41 			__vm_lock();
42 		}
43 		volatile void *prev = m->_m_prev;
44 		volatile void *next = m->_m_next;
45 		*(volatile void *volatile *)prev = next;
46 		if (next != &self->robust_list.head) *(volatile void *volatile *)
47 			((char *)next - sizeof(void *)) = prev;
48 	}
49 #ifdef __LITEOS_A__
50 	cont = a_swap(&m->_m_lock, new);
51 #else
52 	if (type&8) {
53 		if (old<0 || a_cas(&m->_m_lock, old, new)!=old) {
54 			if (new) a_store(&m->_m_waiters, -1);
55 			__syscall(SYS_futex, &m->_m_lock, FUTEX_UNLOCK_PI|priv);
56 		}
57 		cont = 0;
58 		waiters = 0;
59 	} else {
60 		cont = a_swap(&m->_m_lock, new);
61 	}
62 #endif
63 
64 	if (type != PTHREAD_MUTEX_NORMAL && !priv) {
65 		self->robust_list.pending = 0;
66 		__vm_unlock();
67 	}
68 	if (waiters || cont<0)
69 		__wake(&m->_m_lock, 1, priv);
70 	return 0;
71 }
72 
73 weak_alias(__pthread_mutex_unlock, pthread_mutex_unlock);
74