1 files changed, 124 insertions, 0 deletions
diff --git a/zen/sys_error.h b/zen/sys_error.h
new file mode 100644
index 00000000..bbac2eaa
--- /dev/null
+++ b/zen/sys_error.h
@@ -0,0 +1,124 @@
+// **************************************************************************
+// * This file is part of the FreeFileSync project. It is distributed under *
+// * GNU General Public License: http://www.gnu.org/licenses/gpl.html       *
+// * Copyright (C) Zenju (zenju AT gmx DOT de) - All Rights Reserved        *
+// **************************************************************************
+
+#ifndef LAST_ERROR_H_3284791347018951324534
+#define LAST_ERROR_H_3284791347018951324534
+
+#include <string>
+#include "utf.h"
+#include "i18n.h"
+#include "scope_guard.h"
+
+#ifdef ZEN_WIN
+#include "win.h" //includes "windows.h"
+
+#elif defined ZEN_LINUX || defined ZEN_MAC
+#include <cstring>
+#include <cerrno>
+#endif
+
+
+namespace zen
+{
+//evaluate GetLastError()/errno and assemble specific error message
+#ifdef ZEN_WIN
+typedef DWORD ErrorCode;
+#elif defined ZEN_LINUX || defined ZEN_MAC
+typedef int ErrorCode;
+#endif
+
+ErrorCode getLastError();
+
+std::wstring formatSystemError(const std::wstring& functionName, ErrorCode lastError);
+
+bool errorCodeForNotExisting(ErrorCode lastError); //check for "not existing" aliases
+
+
+//A low-level exception class giving (non-translated) detail information only - same conceptional level like "GetLastError()"!
+class SysError
+{
+public:
+    explicit SysError(const std::wstring& msg) : msg_(msg) {}
+    const std::wstring& toString() const { return msg_; }
+
+private:
+    std::wstring msg_;
+};
+
+
+
+
+
+
+
+
+//######################## implementation ########################
+inline
+ErrorCode getLastError()
+{
+#ifdef ZEN_WIN
+    return ::GetLastError();
+#elif defined ZEN_LINUX || defined ZEN_MAC
+    return errno; //don't use "::", errno is a macro!
+#endif
+}
+
+
+std::wstring formatSystemError(const std::wstring& functionName, long long lastError); //not implemented! intentional overload ambiguity to catch usage errors with HRESULT!
+
+
+inline
+std::wstring formatSystemError(const std::wstring& functionName, ErrorCode lastError)
+{
+    //determine error code if none was specified -> still required??
+    if (lastError == 0)
+        lastError = getLastError();
+
+    std::wstring output = replaceCpy(_("Error Code %x:"), L"%x", numberTo<std::wstring>(lastError));
+
+#ifdef ZEN_WIN
+    LPWSTR buffer = nullptr;
+    if (::FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM    |
+                        FORMAT_MESSAGE_MAX_WIDTH_MASK |
+                        FORMAT_MESSAGE_IGNORE_INSERTS | //important: without this flag ::FormatMessage() will fail if message contains placeholders
+                        FORMAT_MESSAGE_ALLOCATE_BUFFER, nullptr, lastError, 0, reinterpret_cast<LPWSTR>(&buffer), 0, nullptr) != 0)
+        if (buffer) //"don't trust nobody"
+        {
+            ZEN_ON_SCOPE_EXIT(::LocalFree(buffer));
+            output += L" ";
+            output += buffer;
+        }
+    ::SetLastError(lastError); //restore last error
+
+#elif defined ZEN_LINUX || defined ZEN_MAC
+    output += L" ";
+    output += utfCvrtTo<std::wstring>(::strerror(lastError));
+
+    errno = lastError; //restore errno
+#endif
+    if (!endsWith(output, L" ")) //Windows messages seem to end with a blank...
+        output += L" ";
+    output += L"(" + functionName + L")";
+
+    return output;
+}
+
+
+inline
+bool errorCodeForNotExisting(ErrorCode lastError)
+{
+#ifdef ZEN_WIN
+    return lastError == ERROR_FILE_NOT_FOUND ||
+           lastError == ERROR_PATH_NOT_FOUND ||
+           lastError == ERROR_BAD_NETPATH    ||
+           lastError == ERROR_NETNAME_DELETED;
+#elif defined ZEN_LINUX || defined ZEN_MAC
+    return lastError == ENOENT;
+#endif
+}
+}
+
+#endif //LAST_ERROR_H_3284791347018951324534