Refactor mutex implementation for Windows platform

Author: mutouyun

include/libipc/mutex.h

@@ -0,0 +1,46 @@
+/**
+ * \file libipc/mutex.h
+ * \author mutouyun ([email protected])
+ * \brief A synchronization primitive that can be used to protect shared data 
+ *        from being simultaneously accessed by multiple processes.
+ */
+#pragma once
+
+#include <string>
+#include <cstddef>
+#include <cstdint>
+
+#include "libimp/export.h"
+#include "libimp/result.h"
+#include "libimp/span.h"
+#include "libimp/byte.h"
+
+#include "libipc/def.h"
+
+LIBIPC_NAMESPACE_BEG_
+
+struct mutex_handle;
+using mutex_t = mutex_handle *;
+
+/// \brief Create or open a mutex object based on memory.
+LIBIMP_EXPORT ::LIBIMP::result<mutex_t> mutex_open(::LIBIMP::span<::LIBIMP::byte>) noexcept;
+
+/// \brief Close the mutex handle.
+/// \note The mutex object will be destroyed when the last handle is closed,
+///       and the lifetime of a mutex object needs to be shorter than 
+///       the memory specified when it is created or opened.
+LIBIMP_EXPORT ::LIBIMP::result<void> mutex_close(mutex_t) noexcept;
+
+/// \brief Gets the memory size of the specified mutex.
+LIBIMP_EXPORT ::LIBIMP::result<std::size_t> mutex_size(mutex_t) noexcept;
+
+/// \brief Locks the mutex, blocks if the mutex is not available.
+LIBIMP_EXPORT ::LIBIMP::result<bool> mutex_lock(mutex_t, std::int64_t ms) noexcept;
+
+/// \brief Tries to lock the mutex, returns if the mutex is not available.
+LIBIMP_EXPORT ::LIBIMP::result<bool> mutex_try_lock(mutex_t) noexcept;
+
+/// \brief Unlocks the mutex.
+LIBIMP_EXPORT ::LIBIMP::result<bool> mutex_unlock(mutex_t) noexcept;
+
+LIBIPC_NAMESPACE_END_

src/libipc/mutex.cpp

@@ -0,0 +1,18 @@
+
+#include "libimp/log.h"
+
+#include "libimp/detect_plat.h"
+#if defined(LIBIMP_OS_WIN)
+# include "libipc/platform/win/mutex_impl.h"
+#else
+#endif
+
+#if !defined(LIBIMP_OS_LINUX)
+LIBIPC_NAMESPACE_BEG_
+
+/// \brief C style mutex access interface implementation.
+
+/// \brief The mutex object.
+
+LIBIPC_NAMESPACE_END_
+#endif

src/libipc/platform/win/mutex_impl.h

@@ -0,0 +1,85 @@
+/**
+ * \file libipc/platform/win/mutex_impl.h
+ * \author mutouyun ([email protected])
+ */
+#pragma once
+
+#include "libimp/log.h"
+#include "libimp/system.h"
+#include "libipc/mutex.h"
+
+#include "api.h"
+
+LIBIPC_NAMESPACE_BEG_
+
+using namespace ::LIBIMP;
+
+struct mutex_handle {
+
+};
+
+namespace winapi {
+
+/**
+ * \brief Creates or opens a named or unnamed mutex object.
+ * \see https://learn.microsoft.com/en-us/windows/win32/api/synchapi/nf-synchapi-createmutexa
+ * \return Mutex object HANDLE, NULL on error.
+ */
+result<HANDLE> mutex_open_or_create(char const *name, bool initial_owner) noexcept {
+  LIBIMP_LOG_();
+  HANDLE h = ::CreateMutexA(winapi::get_sa(), initial_owner, name);
+  if (h == NULL) {
+    auto err = sys::error();
+    log.error("failed: CreateMutexA(", initial_owner, ", ", name, "). error = ", err);
+    return err;
+  }
+  return h;
+}
+
+/**
+ * \brief Releases ownership of the specified mutex object.
+ * \see https://docs.microsoft.com/en-us/windows/win32/api/synchapi/nf-synchapi-releasemutex
+*/
+result<bool> mutex_release(HANDLE h) noexcept {
+  LIBIMP_LOG_();
+  if (::ReleaseMutex(h)) {
+    return true;
+  }
+  auto err = sys::error();
+  log.error("failed: ReleaseMutex. error = ", err);
+  return err;
+}
+
+/**
+ * \brief Locks the mutex, blocks if the mutex is not available.
+ * \see https://docs.microsoft.com/en-us/windows/win32/api/synchapi/nf-synchapi-waitforsingleobject
+*/
+result<bool> mutex_wait(HANDLE h, std::int64_t ms) noexcept {
+  LIBIMP_LOG_();
+  for (;;) {
+    auto r = winapi::wait_for_single_object(h, ms);
+    if (!r) {
+      return r.error();
+    }
+    if (*r == winapi::wait_result::object_0) {
+      return true;
+    }
+    if (*r == winapi::wait_result::abandoned) {
+      log.info("failed: WaitForSingleObject(", ms, "). The mutex is abandoned, try again.");
+      auto rr = mutex_release(h);
+      if (rr) {
+        continue;
+      }
+      return rr.error();
+    }
+    return false;
+  }
+}
+
+} // namespace winapi
+
+result<mutex_t> mutex_open(span<::LIBIMP::byte> mem) noexcept {
+  return {};
+}
+
+LIBIPC_NAMESPACE_END_