Sync to the latest version.

Can be broken or partially implemented.

src/thread_null.c

@@ -0,0 +1,113 @@
+#include <bh/internal/thread.h>
+
+int bh_thread_init(bh_thread_t *thread,
+                   bh_task_t *task)
+{
+    (void)thread;
+    (void)task;
+    return -1;
+}
+
+bh_thread_t *bh_thread_new(bh_task_t *task)
+{
+    (void)task;
+    return NULL;
+}
+
+int bh_thread_join(bh_thread_t *thread)
+{
+    (void)thread;
+    return -1;
+}
+
+int bh_thread_detach(bh_thread_t *thread)
+{
+    (void)thread;
+    return -1;
+}
+
+int bh_mutex_init(bh_mutex_t *mutex)
+{
+    (void)mutex;
+    return -1;
+}
+
+void bh_mutex_destroy(bh_mutex_t *mutex)
+{
+    (void)mutex;
+}
+
+int bh_mutex_lock(bh_mutex_t *mutex)
+{
+    (void)mutex;
+    return -1;
+}
+
+int bh_mutex_try_lock(bh_mutex_t *mutex)
+{
+    (void)mutex;
+    return -1;
+}
+
+int bh_mutex_unlock(bh_mutex_t *mutex)
+{
+    (void)mutex;
+    return -1;
+}
+
+int bh_cond_init(bh_cond_t *cond)
+{
+    (void)cond;
+    return -1;
+}
+
+void bh_cond_destroy(bh_cond_t *cond)
+{
+    (void)cond;
+}
+
+int bh_cond_wait(bh_cond_t *cond,
+                 bh_mutex_t *mutex)
+{
+    (void)cond;
+    (void)mutex;
+    return -1;
+}
+
+int bh_cond_wait_for(bh_cond_t *cond,
+                     bh_mutex_t *mutex,
+                     unsigned long timeout)
+{
+    (void)cond;
+    (void)mutex;
+    (void)timeout;
+    return -1;
+}
+
+int bh_cond_signal(bh_cond_t *cond)
+{
+    (void)cond;
+    return -1;
+}
+
+int bh_cond_broadcast(bh_cond_t *cond)
+{
+    (void)cond;
+    return -1;
+}
+
+int bh_thread_pool_init(bh_thread_pool_t *pool,
+                        size_t size)
+{
+    (void)pool;
+    (void)size;
+    return -1;
+}
+
+bh_thread_pool_t *bh_thread_pool_new(size_t size)
+{
+    (void)size;
+    return NULL;
+}
+
+