added better network error message support.

lib/base/XBase.cpp

@@ -18,6 +18,7 @@
 
 // win32 wants a const char* argument to std::exception c'tor
 #if WINDOWS_LIKE
+#include <windows.h>
 #define STDEXCEPTARG ""
 #endif
 
@@ -85,17 +86,32 @@ XBase::format(const char* /*id*/, const char* fmt, ...) const throw()
 //
 
 MXErrno::MXErrno() :
-	m_errno(errno)
+#if WINDOWS_LIKE
+	m_errno(GetLastError()),
+#else
+	m_errno(errno),
+#endif
+	m_string(NULL)
 {
 	// do nothing
 }
 
 MXErrno::MXErrno(int err) :
-	m_errno(err)
+	m_errno(err),
+	m_string(NULL)
 {
 	// do nothing
 }
 
+MXErrno::~MXErrno()
+{
+	if (m_string != NULL) {
+#if WINDOWS_LIKE
+		LocalFree(m_string);
+#endif
+	}
+}
+
 int
 MXErrno::getErrno() const
 {
@@ -105,5 +121,23 @@ MXErrno::getErrno() const
 const char*
 MXErrno::getErrstr() const
 {
-	return strerror(m_errno);
+#if WINDOWS_LIKE
+	if (m_string != NULL) {
+		if (FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER |
+								FORMAT_MESSAGE_IGNORE_INSERTS |
+								FORMAT_MESSAGE_FROM_SYSTEM,
+								0,
+								error,
+								MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
+								(LPTSTR)&m_string,
+								0,
+								NULL) == 0) {
+			m_string = NULL;
+			return "unknown error";
+		}
+	}
+	return m_string;
+#else
+	return strerror(m_errno);
+#endif
 }

lib/base/XBase.h

@@ -55,7 +55,7 @@ private:
 //! Mix-in for handling \c errno
 /*!
 This mix-in class for exception classes provides storage and query of
-\c errno.
+\c errno.  On Windows, it uses GetLastError() instead of errno.
 */
 class MXErrno {
 public:
@@ -63,6 +63,7 @@ public:
 	MXErrno();
 	//! Save \c err as the error code
 	MXErrno(int err);
+	virtual ~MXErrno();
 
 	//! @name accessors
 	//@{
@@ -71,12 +72,13 @@ public:
 	int					getErrno() const;
 
 	//! Get the human readable string for the error code
-	const char*			getErrstr() const;
+	virtual const char*	getErrstr() const;
 
 	//@}
 
 private:
 	int					m_errno;
+	mutable char*		m_string;
 };
 
 #endif

lib/io/XIO.cpp

@@ -14,34 +14,6 @@
 
 #include "XIO.h"
 
-//
-// XIOErrno
-//
-
-XIOErrno::XIOErrno() :
-	MXErrno()
-{
-	// do nothing
-}
-
-XIOErrno::XIOErrno(int err) :
-	MXErrno(err)
-{
-	// do nothing
-}
-
-
-//
-// XIOClose
-//
-
-CString
-XIOClose::getWhat() const throw()
-{
-	return format("XIOClose", "close: %{1}", XIOErrno::getErrstr());
-}
-
-
 //
 // XIOClosed
 //

lib/io/XIO.h

@@ -20,22 +20,11 @@
 //! Generic I/O exception
 class XIO : public XBase { };
 
-//! Generic I/O exception using \c errno
-class XIOErrno : public XIO, public MXErrno {
-public:
-	XIOErrno();
-	XIOErrno(int);
-};
-
 //! I/O closing exception
 /*!
 Thrown if a stream cannot be closed.
 */
-class XIOClose: public XIOErrno {
+class XIOClose : public XIO { };
-protected:
-	// XBase overrides
-	virtual CString		getWhat() const throw();
-};
 
 //! I/O already closed exception
 /*!

lib/net/CTCPListenSocket.cpp

@@ -84,7 +84,7 @@ CTCPListenSocket::close()
 		throw XIOClosed();
 	}
 	if (CNetwork::close(m_fd) == CNetwork::Error) {
-		throw XIOClose();
+		throw XSocketIOClose();
 	}
 	m_fd = CNetwork::Null;
 }

lib/net/CTCPSocket.cpp

@@ -114,7 +114,7 @@ CTCPSocket::close()
 	// close socket
 	if (m_fd != CNetwork::Null) {
 		if (CNetwork::close(m_fd) == CNetwork::Error) {
-			throw XIOClose();
+			throw XSocketIOClose();
 		}
 		m_fd = CNetwork::Null;
 	}

lib/net/XSocket.cpp

@@ -13,6 +13,7 @@
  */
 
 #include "XSocket.h"
+#include "CNetwork.h"
 
 //
 // XSocketAddress
@@ -71,7 +72,7 @@ XSocketAddress::getWhat() const throw()
 //
 
 XSocketErrno::XSocketErrno() :
-	MXErrno()
+	MXErrno(CNetwork::getsockerror())
 {
 	// do nothing
 }
@@ -82,6 +83,92 @@ XSocketErrno::XSocketErrno(int err) :
 	// do nothing
 }
 
+const char*
+XSocketErrno::getErrstr() const
+{
+#if WINDOWS_LIKE
+	// built-in windows function for looking up error message strings
+	// may not look up network error messages correctly.  we'll have
+	// to do it ourself.
+	static const struct { int m_code; const char* m_msg; } s_netErrorCodes[] = {
+		/* 10004 */{WSAEINTR,		"The (blocking) call was canceled via WSACancelBlockingCall"},
+		/* 10009 */{WSAEBADF,		"Bad file handle"},
+		/* 10013 */{WSAEACCES,		"The requested address is a broadcast address, but the appropriate flag was not set"},
+		/* 10014 */{WSAEFAULT,		"WSAEFAULT"},
+		/* 10022 */{WSAEINVAL,		"WSAEINVAL"},
+		/* 10024 */{WSAEMFILE,		"No more file descriptors available"},
+		/* 10035 */{WSAEWOULDBLOCK,	"Socket is marked as non-blocking and no connections are present or the receive operation would block"},
+		/* 10036 */{WSAEINPROGRESS,	"A blocking Windows Sockets operation is in progress"},
+		/* 10037 */{WSAEALREADY,	"The asynchronous routine being canceled has already completed"},
+		/* 10038 */{WSAENOTSOCK,	"At least on descriptor is not a socket"},
+		/* 10039 */{WSAEDESTADDRREQ,	"A destination address is required"},
+		/* 10040 */{WSAEMSGSIZE,	"The datagram was too large to fit into the specified buffer and was truncated"},
+		/* 10041 */{WSAEPROTOTYPE,	"The specified protocol is the wrong type for this socket"},
+		/* 10042 */{WSAENOPROTOOPT,	"The option is unknown or unsupported"},
+		/* 10043 */{WSAEPROTONOSUPPORT,"The specified protocol is not supported"},
+		/* 10044 */{WSAESOCKTNOSUPPORT,"The specified socket type is not supported by this address family"},
+		/* 10045 */{WSAEOPNOTSUPP,	"The referenced socket is not a type that supports that operation"},
+		/* 10046 */{WSAEPFNOSUPPORT,	"BSD: Protocol family not supported"},
+		/* 10047 */{WSAEAFNOSUPPORT,	"The specified address family is not supported"},
+		/* 10048 */{WSAEADDRINUSE,	"The specified address is already in use"},
+		/* 10049 */{WSAEADDRNOTAVAIL,	"The specified address is not available from the local machine"},
+		/* 10050 */{WSAENETDOWN,	"The Windows Sockets implementation has detected that the network subsystem has failed"},
+		/* 10051 */{WSAENETUNREACH,	"The network can't be reached from this hos at this time"},
+		/* 10052 */{WSAENETRESET,	"The connection must be reset because the Windows Sockets implementation dropped it"},
+		/* 10053 */{WSAECONNABORTED,	"The virtual circuit was aborted due to timeout or other failure"},
+		/* 10054 */{WSAECONNRESET,	"The virtual circuit was reset by the remote side"},
+		/* 10055 */{WSAENOBUFS,		"No buffer space is available or a buffer deadlock has occured. The socket cannot be created"},
+		/* 10056 */{WSAEISCONN,		"The socket is already connected"},
+		/* 10057 */{WSAENOTCONN,	"The socket is not connected"},
+		/* 10058 */{WSAESHUTDOWN,	"The socket has been shutdown"},
+		/* 10059 */{WSAETOOMANYREFS,	"BSD: Too many references"},
+		/* 10060 */{WSAETIMEDOUT,	"Attempt to connect timed out without establishing a connection"},
+		/* 10061 */{WSAECONNREFUSED,	"The attempt to connect was forcefully rejected"},
+		/* 10062 */{WSAELOOP,		"Undocumented WinSock error code used in BSD"},
+		/* 10063 */{WSAENAMETOOLONG,	"Undocumented WinSock error code used in BSD"},
+		/* 10064 */{WSAEHOSTDOWN,	"Undocumented WinSock error code used in BSD"},
+		/* 10065 */{WSAEHOSTUNREACH,	"No route to host"},
+		/* 10066 */{WSAENOTEMPTY,	"Undocumented WinSock error code"},
+		/* 10067 */{WSAEPROCLIM,	"Undocumented WinSock error code"},
+		/* 10068 */{WSAEUSERS,		"Undocumented WinSock error code"},
+		/* 10069 */{WSAEDQUOT,		"Undocumented WinSock error code"},
+		/* 10070 */{WSAESTALE,		"Undocumented WinSock error code"},
+		/* 10071 */{WSAEREMOTE,		"Undocumented WinSock error code"},
+		/* 10091 */{WSASYSNOTREADY,	"Underlying network subsytem is not ready for network communication"},
+		/* 10092 */{WSAVERNOTSUPPORTED,	"The version of WinSock API support requested is not provided in this implementation"},
+		/* 10093 */{WSANOTINITIALISED,	"WinSock subsystem not properly initialized"},
+		/* 10101 */{WSAEDISCON,		"Virtual circuit has gracefully terminated connection"},
+		/* 11001 */{WSAHOST_NOT_FOUND,	"Host not found"},
+		/* 11002 */{WSATRY_AGAIN,	"Host not found"},
+		/* 11003 */{WSANO_RECOVERY,	"Host name lookup error"},
+		/* 11004 */{WSANO_DATA,		"No data for host"},
+		/* end   */{0,			NULL}
+	};
+
+	const int err = getErrno();
+	for (unsigned int i = 0; s_netErrorCodes[i].m_code != 0; ++i) {
+		if (s_netErrorCodes[i].m_code == err) {
+			return s_netErrorCodes[i].m_msg;
+		}
+	}
+#endif
+
+	// not a network error code.  fallback to system error message.
+	return MXErrno::getErrstr();
+}
+
+
+//
+// XSocketIOClose
+//
+
+CString
+XSocketIOClose::getWhat() const throw()
+{
+	return format("XSocketIOClose", "close: %{1}",
+								getErrstr());
+}
+
 
 //
 // XSocketBind
@@ -90,7 +177,8 @@ XSocketErrno::XSocketErrno(int err) :
 CString
 XSocketBind::getWhat() const throw()
 {
-	return format("XSocketBind", "cannot bind address");
+	return format("XSocketBind", "cannot bind address: %{1}",
+								getErrstr());
 }
 
 
@@ -101,7 +189,8 @@ XSocketBind::getWhat() const throw()
 CString
 XSocketConnect::getWhat() const throw()
 {
-	return format("XSocketConnect", "cannot connect socket");
+	return format("XSocketConnect", "cannot connect socket: %{1}",
+								getErrstr());
 }
 
 
@@ -112,5 +201,6 @@ XSocketConnect::getWhat() const throw()
 CString
 XSocketCreate::getWhat() const throw()
 {
-	return format("XSocketCreate", "cannot create socket");
+	return format("XSocketCreate", "cannot create socket: %{1}",
+								getErrstr());
 }

lib/net/XSocket.h

@@ -15,6 +15,7 @@
 #ifndef XSOCKET_H
 #define XSOCKET_H
 
+#include "XIO.h"
 #include "XBase.h"
 #include "CString.h"
 #include "BasicTypes.h"
@@ -61,17 +62,30 @@ private:
 };
 
 //! Generic socket exception using \c errno
-class XSocketErrno : public XSocket, public MXErrno {
+class XSocketErrno : public MXErrno {
 public:
 	XSocketErrno();
 	XSocketErrno(int);
+
+	// MXErrno overrides
+	virtual const char*	getErrstr() const;
+};
+
+//! I/O closing exception
+/*!
+Thrown if a stream cannot be closed.
+*/
+class XSocketIOClose : public XIOClose, public XSocketErrno {
+protected:
+	// XBase overrides
+	virtual CString		getWhat() const throw();
 };
 
 //! Socket cannot bind address exception
 /*!
 Thrown when a socket cannot be bound to an address.
 */
-class XSocketBind : public XSocketErrno {
+class XSocketBind : public XSocket, public XSocketErrno {
 public:
 	XSocketBind() { }
 	XSocketBind(int e) : XSocketErrno(e) { }
@@ -96,7 +110,7 @@ public:
 /*!
 Thrown when a socket cannot connect to a remote endpoint.
 */
-class XSocketConnect : public XSocketErrno {
+class XSocketConnect : public XSocket, public XSocketErrno {
 public:
 	XSocketConnect() { }
 	XSocketConnect(int e) : XSocketErrno(e) { }
@@ -110,7 +124,7 @@ protected:
 /*!
 Thrown when a socket cannot be created (by the operating system).
 */
-class XSocketCreate : public XSocketErrno {
+class XSocketCreate : public XSocket, public XSocketErrno {
 public:
 	XSocketCreate() { }
 	XSocketCreate(int e) : XSocketErrno(e) { }