refactor zen command return value handling (#487)

- Improvement: Use consistent language for command line argument parsing errors
- Improvement: Changed zen command parsing errors to output help first and error last to make it easier to spot the error
- Improvement: Refactor zen command return codes to conform to valid Linux range (0-255)

        kSuccess     = 0,
        kOtherError  = 1,
        kBadInput    = 2,

        kOutOfMemory = 16,
        kOutOfDisk   = 17,

        kAssertError = 70,
        
        kHttpOtherClientError = 80,
        kHttpCantConnectError = 81,
        kHttpNotFound         = 66,  // NotFound(404)
        kHttpUnauthorized     = 77,  // Unauthorized(401),
        kHttpSLLError         = 82,
        kHttpForbidden        = 83,  // Forbidden(403)
        kHttpTimeout          = 84,  // RequestTimeout(408)
        kHttpConflict         = 85,  // Conflict(409)
        kHttpNoHost           = 86,
        
        kHttpOtherServerError	   = 90,
        kHttpInternalServerError = 91,  // InternalServerError(500)
        kHttpServiceUnavailable  = 69,  // ServiceUnavailable(503)
        kHttpBadGateway          = 92,  // BadGateway(502)
        kHttpGatewayTimeout      = 93,  // GatewayTimeout(504)

2 files changed, 5 insertions, 3 deletions

diff --git a/src/zencore/include/zencore/except.h b/src/zencore/include/zencore/except.h
index 6810e6ea9..c933adfd8 100644
--- a/src/zencore/include/zencore/except.h
+++ b/src/zencore/include/zencore/except.h
@@ -63,7 +63,9 @@ MakeErrorCodeFromLastError() noexcept
 class OptionParseException : public std::runtime_error
 {
 public:
-	inline explicit OptionParseException(const std::string& Message) : std::runtime_error(Message) {}
+	//	inline explicit OptionParseException(const std::string& Message) : std::runtime_error(Message) {}
+	inline OptionParseException(const std::string& Message, const std::string& Help) : std::runtime_error(Message), m_Help(Help) {}
+	const std::string m_Help;
 };
 
 bool IsOOM(const std::system_error& SystemError);
diff --git a/src/zencore/include/zencore/uid.h b/src/zencore/include/zencore/uid.h
index 64d3b6b9b..0c1079444 100644
--- a/src/zencore/include/zencore/uid.h
+++ b/src/zencore/include/zencore/uid.h
@@ -55,8 +55,8 @@ class StringBuilderBase;
 
 struct Oid
 {
-	static const int StringLength = 24;
-	typedef char	 String_t[StringLength + 1];
+	static constexpr int StringLength = 24;
+	typedef char		 String_t[StringLength + 1];
 
 	static void				 Initialize();
 	[[nodiscard]] static Oid NewOid();