1 files changed, 262 insertions, 0 deletions
diff --git a/src/util/win32/thread.c b/src/util/win32/thread.c
new file mode 100644
index 000000000..f5cacd320
--- /dev/null
+++ b/src/util/win32/thread.c
@@ -0,0 +1,262 @@
+/*
+ * Copyright (C) the libgit2 contributors. All rights reserved.
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+
+#include "thread.h"
+#include "runtime.h"
+
+#define CLEAN_THREAD_EXIT 0x6F012842
+
+typedef void (WINAPI *win32_srwlock_fn)(GIT_SRWLOCK *);
+
+static win32_srwlock_fn win32_srwlock_initialize;
+static win32_srwlock_fn win32_srwlock_acquire_shared;
+static win32_srwlock_fn win32_srwlock_release_shared;
+static win32_srwlock_fn win32_srwlock_acquire_exclusive;
+static win32_srwlock_fn win32_srwlock_release_exclusive;
+
+static DWORD fls_index;
+
+/* The thread procedure stub used to invoke the caller's procedure
+ * and capture the return value for later collection. Windows will
+ * only hold a DWORD, but we need to be able to store an entire
+ * void pointer. This requires the indirection. */
+static DWORD WINAPI git_win32__threadproc(LPVOID lpParameter)
+{
+	git_thread *thread = lpParameter;
+
+	/* Set the current thread for `git_thread_exit` */
+	FlsSetValue(fls_index, thread);
+
+	thread->result = thread->proc(thread->param);
+
+	return CLEAN_THREAD_EXIT;
+}
+
+static void git_threads_global_shutdown(void)
+{
+	FlsFree(fls_index);
+}
+
+int git_threads_global_init(void)
+{
+	HMODULE hModule = GetModuleHandleW(L"kernel32");
+
+	if (hModule) {
+		win32_srwlock_initialize = (win32_srwlock_fn)(void *)
+			GetProcAddress(hModule, "InitializeSRWLock");
+		win32_srwlock_acquire_shared = (win32_srwlock_fn)(void *)
+			GetProcAddress(hModule, "AcquireSRWLockShared");
+		win32_srwlock_release_shared = (win32_srwlock_fn)(void *)
+			GetProcAddress(hModule, "ReleaseSRWLockShared");
+		win32_srwlock_acquire_exclusive = (win32_srwlock_fn)(void *)
+			GetProcAddress(hModule, "AcquireSRWLockExclusive");
+		win32_srwlock_release_exclusive = (win32_srwlock_fn)(void *)
+			GetProcAddress(hModule, "ReleaseSRWLockExclusive");
+	}
+
+	if ((fls_index = FlsAlloc(NULL)) == FLS_OUT_OF_INDEXES)
+		return -1;
+
+	return git_runtime_shutdown_register(git_threads_global_shutdown);
+}
+
+int git_thread_create(
+	git_thread *GIT_RESTRICT thread,
+	void *(*start_routine)(void*),
+	void *GIT_RESTRICT arg)
+{
+	thread->result = NULL;
+	thread->param = arg;
+	thread->proc = start_routine;
+	thread->thread = CreateThread(
+		NULL, 0, git_win32__threadproc, thread, 0, NULL);
+
+	return thread->thread ? 0 : -1;
+}
+
+int git_thread_join(
+	git_thread *thread,
+	void **value_ptr)
+{
+	DWORD exit;
+
+	if (WaitForSingleObject(thread->thread, INFINITE) != WAIT_OBJECT_0)
+		return -1;
+
+	if (!GetExitCodeThread(thread->thread, &exit)) {
+		CloseHandle(thread->thread);
+		return -1;
+	}
+
+	/* Check for the thread having exited uncleanly. If exit was unclean,
+	 * then we don't have a return value to give back to the caller. */
+	GIT_ASSERT(exit == CLEAN_THREAD_EXIT);
+
+	if (value_ptr)
+		*value_ptr = thread->result;
+
+	CloseHandle(thread->thread);
+	return 0;
+}
+
+void git_thread_exit(void *value)
+{
+	git_thread *thread = FlsGetValue(fls_index);
+
+	if (thread)
+		thread->result = value;
+
+	ExitThread(CLEAN_THREAD_EXIT);
+}
+
+size_t git_thread_currentid(void)
+{
+	return GetCurrentThreadId();
+}
+
+int git_mutex_init(git_mutex *GIT_RESTRICT mutex)
+{
+	InitializeCriticalSection(mutex);
+	return 0;
+}
+
+int git_mutex_free(git_mutex *mutex)
+{
+	DeleteCriticalSection(mutex);
+	return 0;
+}
+
+int git_mutex_lock(git_mutex *mutex)
+{
+	EnterCriticalSection(mutex);
+	return 0;
+}
+
+int git_mutex_unlock(git_mutex *mutex)
+{
+	LeaveCriticalSection(mutex);
+	return 0;
+}
+
+int git_cond_init(git_cond *cond)
+{
+	/* This is an auto-reset event. */
+	*cond = CreateEventW(NULL, FALSE, FALSE, NULL);
+	GIT_ASSERT(*cond);
+
+	/* If we can't create the event, claim that the reason was out-of-memory.
+	 * The actual reason can be fetched with GetLastError(). */
+	return *cond ? 0 : ENOMEM;
+}
+
+int git_cond_free(git_cond *cond)
+{
+	BOOL closed;
+
+	if (!cond)
+		return EINVAL;
+
+	closed = CloseHandle(*cond);
+	GIT_ASSERT(closed);
+	GIT_UNUSED(closed);
+
+	*cond = NULL;
+	return 0;
+}
+
+int git_cond_wait(git_cond *cond, git_mutex *mutex)
+{
+	int error;
+	DWORD wait_result;
+
+	if (!cond || !mutex)
+		return EINVAL;
+
+	/* The caller must be holding the mutex. */
+	error = git_mutex_unlock(mutex);
+
+	if (error)
+		return error;
+
+	wait_result = WaitForSingleObject(*cond, INFINITE);
+	GIT_ASSERT(WAIT_OBJECT_0 == wait_result);
+	GIT_UNUSED(wait_result);
+
+	return git_mutex_lock(mutex);
+}
+
+int git_cond_signal(git_cond *cond)
+{
+	BOOL signaled;
+
+	if (!cond)
+		return EINVAL;
+
+	signaled = SetEvent(*cond);
+	GIT_ASSERT(signaled);
+	GIT_UNUSED(signaled);
+
+	return 0;
+}
+
+int git_rwlock_init(git_rwlock *GIT_RESTRICT lock)
+{
+	if (win32_srwlock_initialize)
+		win32_srwlock_initialize(&lock->native.srwl);
+	else
+		InitializeCriticalSection(&lock->native.csec);
+
+	return 0;
+}
+
+int git_rwlock_rdlock(git_rwlock *lock)
+{
+	if (win32_srwlock_acquire_shared)
+		win32_srwlock_acquire_shared(&lock->native.srwl);
+	else
+		EnterCriticalSection(&lock->native.csec);
+
+	return 0;
+}
+
+int git_rwlock_rdunlock(git_rwlock *lock)
+{
+	if (win32_srwlock_release_shared)
+		win32_srwlock_release_shared(&lock->native.srwl);
+	else
+		LeaveCriticalSection(&lock->native.csec);
+
+	return 0;
+}
+
+int git_rwlock_wrlock(git_rwlock *lock)
+{
+	if (win32_srwlock_acquire_exclusive)
+		win32_srwlock_acquire_exclusive(&lock->native.srwl);
+	else
+		EnterCriticalSection(&lock->native.csec);
+
+	return 0;
+}
+
+int git_rwlock_wrunlock(git_rwlock *lock)
+{
+	if (win32_srwlock_release_exclusive)
+		win32_srwlock_release_exclusive(&lock->native.srwl);
+	else
+		LeaveCriticalSection(&lock->native.csec);
+
+	return 0;
+}
+
+int git_rwlock_free(git_rwlock *lock)
+{
+	if (!win32_srwlock_initialize)
+		DeleteCriticalSection(&lock->native.csec);
+	git__memzero(lock, sizeof(*lock));
+	return 0;
+}