1 files changed, 87 insertions, 0 deletions
diff --git a/Source/cmFileLockWin32.cxx b/Source/cmFileLockWin32.cxx
new file mode 100644
index 0000000..a61d360
--- /dev/null
+++ b/Source/cmFileLockWin32.cxx
@@ -0,0 +1,87 @@
+/* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
+   file Copyright.txt or https://cmake.org/licensing for details.  */
+#include "cmFileLock.h"
+
+#include "cmSystemTools.h"
+#include <windows.h> // CreateFileW
+
+cmFileLock::cmFileLock()
+{
+}
+
+cmFileLockResult cmFileLock::Release()
+{
+  if (this->Filename.empty()) {
+    return cmFileLockResult::MakeOk();
+  }
+  const unsigned long len = static_cast<unsigned long>(-1);
+  static OVERLAPPED overlapped;
+  const DWORD reserved = 0;
+  const BOOL unlockResult =
+    UnlockFileEx(File, reserved, len, len, &overlapped);
+
+  this->Filename = "";
+
+  CloseHandle(this->File);
+  this->File = INVALID_HANDLE_VALUE;
+
+  if (unlockResult) {
+    return cmFileLockResult::MakeOk();
+  } else {
+    return cmFileLockResult::MakeSystem();
+  }
+}
+
+cmFileLockResult cmFileLock::OpenFile()
+{
+  const DWORD access = GENERIC_READ | GENERIC_WRITE;
+  const DWORD shareMode = FILE_SHARE_READ | FILE_SHARE_WRITE;
+  const PSECURITY_ATTRIBUTES security = NULL;
+  const DWORD attr = 0;
+  const HANDLE templ = NULL;
+  this->File = CreateFileW(
+    cmSystemTools::ConvertToWindowsExtendedPath(this->Filename).c_str(),
+    access, shareMode, security, OPEN_EXISTING, attr, templ);
+  if (this->File == INVALID_HANDLE_VALUE) {
+    return cmFileLockResult::MakeSystem();
+  } else {
+    return cmFileLockResult::MakeOk();
+  }
+}
+
+cmFileLockResult cmFileLock::LockWithoutTimeout()
+{
+  if (!this->LockFile(LOCKFILE_EXCLUSIVE_LOCK)) {
+    return cmFileLockResult::MakeSystem();
+  } else {
+    return cmFileLockResult::MakeOk();
+  }
+}
+
+cmFileLockResult cmFileLock::LockWithTimeout(unsigned long seconds)
+{
+  const DWORD flags = LOCKFILE_EXCLUSIVE_LOCK | LOCKFILE_FAIL_IMMEDIATELY;
+  while (true) {
+    const BOOL result = this->LockFile(flags);
+    if (result) {
+      return cmFileLockResult::MakeOk();
+    }
+    const DWORD error = GetLastError();
+    if (error != ERROR_LOCK_VIOLATION) {
+      return cmFileLockResult::MakeSystem();
+    }
+    if (seconds == 0) {
+      return cmFileLockResult::MakeTimeout();
+    }
+    --seconds;
+    cmSystemTools::Delay(1000);
+  }
+}
+
+BOOL cmFileLock::LockFile(DWORD flags)
+{
+  const DWORD reserved = 0;
+  const unsigned long len = static_cast<unsigned long>(-1);
+  static OVERLAPPED overlapped;
+  return LockFileEx(this->File, flags, reserved, len, len, &overlapped);
+}