1 files changed, 193 insertions, 0 deletions
diff --git a/v_windows/v/vlib/sync/sync_default.c.v b/v_windows/v/vlib/sync/sync_default.c.v
new file mode 100644
index 0000000..76f0b44
--- /dev/null
+++ b/v_windows/v/vlib/sync/sync_default.c.v
@@ -0,0 +1,193 @@
+// Copyright (c) 2019-2021 Alexander Medvednikov. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
+module sync
+
+import time
+
+// There's no additional linking (-lpthread) needed for Android.
+// See https://stackoverflow.com/a/31277163/1904615
+$if !android {
+	#flag -lpthread
+}
+
+#include <semaphore.h>
+
+[trusted]
+fn C.pthread_mutex_init(voidptr, voidptr) int
+fn C.pthread_mutex_lock(voidptr) int
+fn C.pthread_mutex_unlock(voidptr) int
+fn C.pthread_mutex_destroy(voidptr) int
+fn C.pthread_rwlockattr_init(voidptr) int
+fn C.pthread_rwlockattr_setkind_np(voidptr, int) int
+fn C.pthread_rwlockattr_setpshared(voidptr, int) int
+fn C.pthread_rwlock_init(voidptr, voidptr) int
+fn C.pthread_rwlock_rdlock(voidptr) int
+fn C.pthread_rwlock_wrlock(voidptr) int
+fn C.pthread_rwlock_unlock(voidptr) int
+fn C.sem_init(voidptr, int, u32) int
+fn C.sem_post(voidptr) int
+fn C.sem_wait(voidptr) int
+fn C.sem_trywait(voidptr) int
+fn C.sem_timedwait(voidptr, voidptr) int
+fn C.sem_destroy(voidptr) int
+
+// [init_with=new_mutex] // TODO: implement support for this struct attribute, and disallow Mutex{} from outside the sync.new_mutex() function.
+[heap]
+pub struct Mutex {
+	mutex C.pthread_mutex_t
+}
+
+[heap]
+pub struct RwMutex {
+	mutex C.pthread_rwlock_t
+}
+
+struct RwMutexAttr {
+	attr C.pthread_rwlockattr_t
+}
+
+[heap]
+struct Semaphore {
+	sem C.sem_t
+}
+
+pub fn new_mutex() &Mutex {
+	mut m := &Mutex{}
+	m.init()
+	return m
+}
+
+pub fn (mut m Mutex) init() {
+	C.pthread_mutex_init(&m.mutex, C.NULL)
+}
+
+pub fn new_rwmutex() &RwMutex {
+	mut m := &RwMutex{}
+	m.init()
+	return m
+}
+
+pub fn (mut m RwMutex) init() {
+	a := RwMutexAttr{}
+	C.pthread_rwlockattr_init(&a.attr)
+	// Give writer priority over readers
+	C.pthread_rwlockattr_setkind_np(&a.attr, C.PTHREAD_RWLOCK_PREFER_WRITER_NONRECURSIVE_NP)
+	C.pthread_rwlockattr_setpshared(&a.attr, C.PTHREAD_PROCESS_PRIVATE)
+	C.pthread_rwlock_init(&m.mutex, &a.attr)
+}
+
+// @lock(), for *manual* mutex handling, since `lock` is a keyword
+pub fn (mut m Mutex) @lock() {
+	C.pthread_mutex_lock(&m.mutex)
+}
+
+pub fn (mut m Mutex) unlock() {
+	C.pthread_mutex_unlock(&m.mutex)
+}
+
+// RwMutex has separate read- and write locks
+pub fn (mut m RwMutex) @rlock() {
+	C.pthread_rwlock_rdlock(&m.mutex)
+}
+
+pub fn (mut m RwMutex) @lock() {
+	C.pthread_rwlock_wrlock(&m.mutex)
+}
+
+// Windows SRWLocks have different function to unlock
+// So provide two functions here, too, to have a common interface
+pub fn (mut m RwMutex) runlock() {
+	C.pthread_rwlock_unlock(&m.mutex)
+}
+
+pub fn (mut m RwMutex) unlock() {
+	C.pthread_rwlock_unlock(&m.mutex)
+}
+
+[inline]
+pub fn new_semaphore() &Semaphore {
+	return new_semaphore_init(0)
+}
+
+pub fn new_semaphore_init(n u32) &Semaphore {
+	mut sem := &Semaphore{}
+	sem.init(n)
+	return sem
+}
+
+pub fn (mut sem Semaphore) init(n u32) {
+	C.sem_init(&sem.sem, 0, n)
+}
+
+pub fn (mut sem Semaphore) post() {
+	C.sem_post(&sem.sem)
+}
+
+pub fn (mut sem Semaphore) wait() {
+	for {
+		if C.sem_wait(&sem.sem) == 0 {
+			return
+		}
+		e := C.errno
+		match e {
+			C.EINTR {
+				continue // interrupted by signal
+			}
+			else {
+				panic(unsafe { tos_clone(&byte(C.strerror(C.errno))) })
+			}
+		}
+	}
+}
+
+// `try_wait()` should return as fast as possible so error handling is only
+// done when debugging
+pub fn (mut sem Semaphore) try_wait() bool {
+	$if !debug {
+		return C.sem_trywait(&sem.sem) == 0
+	} $else {
+		if C.sem_trywait(&sem.sem) != 0 {
+			e := C.errno
+			match e {
+				C.EAGAIN {
+					return false
+				}
+				else {
+					panic(unsafe { tos_clone(&byte(C.strerror(C.errno))) })
+				}
+			}
+		}
+		return true
+	}
+}
+
+pub fn (mut sem Semaphore) timed_wait(timeout time.Duration) bool {
+	t_spec := timeout.timespec()
+	for {
+		if C.sem_timedwait(&sem.sem, &t_spec) == 0 {
+			return true
+		}
+		e := C.errno
+		match e {
+			C.EINTR {
+				continue // interrupted by signal
+			}
+			C.ETIMEDOUT {
+				break
+			}
+			else {
+				panic(unsafe { tos_clone(&byte(C.strerror(e))) })
+			}
+		}
+	}
+	return false
+}
+
+pub fn (sem Semaphore) destroy() {
+	res := C.sem_destroy(&sem.sem)
+	if res == 0 {
+		return
+	}
+	panic(unsafe { tos_clone(&byte(C.strerror(res))) })
+}