OrcLib: add enum class FileDisposition

src/OrcLib/CMakeLists.txt

@@ -254,6 +254,8 @@ source_group(ExtensionLibraries\\Yara FILES ${SRC_EXTENSIONLIBRARIES_YARA})
 set(SRC_INOUT
     "LocationOutput.h"
     "OutputWriter.h"
+    "FileDisposition.h"
+    "FileDisposition.cpp"
 )
 
 source_group(In&Out FILES ${SRC_INOUT})

src/OrcLib/FileDisposition.cpp

@@ -0,0 +1,67 @@
+//
+// SPDX-License-Identifier: LGPL-2.1-or-later
+//
+// Copyright © 2021 ANSSI. All Rights Reserved.
+//
+// Author(s): fabienfl
+//
+
+#include "FileDisposition.h"
+
+#include <string>
+
+namespace Orc {
+
+constexpr std::wstring_view kAppend = L"append";
+constexpr std::wstring_view kTruncate = L"truncate";
+constexpr std::wstring_view kCreateNew = L"create_new";
+constexpr std::wstring_view kUnknown = L"unknown";
+
+std::wstring_view ToString(FileDisposition disposition)
+{
+    switch (disposition)
+    {
+        case FileDisposition::Append:
+            return kAppend;
+        case FileDisposition::Truncate:
+            return kTruncate;
+        case FileDisposition::CreateNew:
+            return kCreateNew;
+        default:
+            return kUnknown;
+    }
+}
+
+FileDisposition ToFileDisposition(const std::wstring& disposition, std::error_code& ec)
+{
+    const std::map<std::wstring_view, FileDisposition> map = {
+        {kAppend, FileDisposition::Append},
+        {kTruncate, FileDisposition::Truncate},
+        {kCreateNew, FileDisposition::CreateNew}};
+
+    auto it = map.find(disposition);
+    if (it == std::cend(map))
+    {
+        ec = std::make_error_code(std::errc::invalid_argument);
+        return FileDisposition::Unknown;
+    }
+
+    return it->second;
+}
+
+std::ios_base::openmode ToOpenMode(FileDisposition disposition)
+{
+    switch (disposition)
+    {
+        case FileDisposition::Append:
+            return std::ios::app;
+        case FileDisposition::CreateNew:
+        case FileDisposition::Truncate:
+            return std::ios_base::trunc;
+        default:
+            assert(nullptr);
+            return std::ios_base::ate;
+    }
+}
+
+}  // namespace Orc

src/OrcLib/FileDisposition.h

@@ -0,0 +1,30 @@
+//
+// SPDX-License-Identifier: LGPL-2.1-or-later
+//
+// Copyright © 2021 ANSSI. All Rights Reserved.
+//
+// Author(s): fabienfl
+//
+
+#pragma once
+
+#include <string_view>
+#include <system_error>
+#include <ios>
+
+namespace Orc {
+
+enum class FileDisposition
+{
+    Unknown,
+    Append,
+    Truncate,
+    CreateNew
+};
+
+std::wstring_view ToString(FileDisposition disposition);
+FileDisposition ToFileDisposition(const std::wstring& disposition, std::error_code& ec = std::error_code());
+
+std::ios_base::openmode ToOpenMode(FileDisposition disposition);
+
+}  // namespace Orc