Common
[Implementation]

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Detailed Description

Common.h provides macro's and classes that must be available to the other files that make up the Rulbus Device Class Library.

It defines the following:

• a DEBUG flag that specifies which items to include
• macro's to declare types and classes
• predefined types
• Assertion and design-by-contract exception classes with accompanying macro's

Common.h must be included by all source files either directly, or indirectly.

Common.h and Assertion draw on the work provided by the CoreLinux++ consortium [CORELINUX++].

Classes
struct	isEqual
	predicate for apgorithms to compare floating types like Volt, Time and Freq.
Defines
#define	DEBUG   DFLAG_NONE
	define the subjects to include in debugging.
#define	DFLAG_NONE   0x0000
	include no debug subjects.
#define	DFLAG_ALL   0xFFFF
	include all debug subjects.
#define	DFLAG_PRODUCTION   (DFLAG_ALL & ~DFLAG_ENSURE)
	include all but ensure debug subjects.
#define	DFLAG_GENERAL   0x0001
	debug subjects combined in one group.
#define	DFLAG_INTERFACE   0x0002
	report more details on Rulbus Interface errors.
#define	DFLAG_BUSVIOLATION   0x0004
	check for Rulbus address/data violations.
#define	DFLAG_REQUIRE   0x0010
	design-by-contract: require pre-condition.
#define	DFLAG_ENSURE   0x0020
	design-by-contract: ensure post-condition.
#define	DFLAG_NEVER_GET_HERE   0x0040
	design-by-contract: ensure never reached.
#define	dim(a)   (sizeof(a)/sizeof((a)[0]))
	array dimension.
#define	DECLARE_TYPE(mydecl, mytype)
	declare a new type and its pointer, const pointer, reference, and const reference types.
#define	DECLARE_CLASS(tag)
	declare class, class pointer, const pointer, class reference and const class reference types for classes.
#define	PROXY_CAST   dynamic_cast
	use dynamic_cast to cast RulbusDevice to actual class type.
Typedefs
typedef isEqual< Volt >	Rulbus::isEqualVolt
	predicate to compare Volt
typedef isEqual< Time >	Rulbus::isEqualTime
	predicate to compare Time
typedef isEqual< Freq >	Rulbus::isEqualFreq
	predicate to compare Freq
typedef signed char	Rulbus::int8
	the compiler's signed 8-bit integral type.
typedef unsigned char	Rulbus::uInt8
	the compiler's unsigned 8-bit integral type.
typedef signed short int	Rulbus::int16
	the compiler's signed 16-bit integral type.
typedef unsigned short int	Rulbus::uInt16
	the compiler's unsigned 16-bit integral type.
typedef signed int	Rulbus::int32
	the compiler's signed 32-bit integral type.
typedef unsigned int	Rulbus::uInt32
	the compiler's unsigned 32-bit integral type.
typedef float	Rulbus::float32
	the compiler's 32-bit real type.
typedef double	Rulbus::float64
	the compiler's 64-bit real type.
typedef uInt8	Rulbus::Byte
	the libraries' byte type.
typedef uInt16	Rulbus::Word
	the libraries' word (2-Byte) type.
typedef uInt32	Rulbus::Quad
	the libraries' double word (4-Byte) type.
typedef char	Rulbus::Char
	the libraries' character type.
typedef int	Rulbus::Int
	the libraries' signed integral type.
typedef int16	Rulbus::Int16
	the libraries' 16-bit signed integral type.
typedef int32	Rulbus::Int32
	the libraries' 32-bit signed integral type.
typedef double	Rulbus::Real
	the libraries' real type.
typedef float32	Rulbus::Real32
	the libraries' 32-bit real type.
typedef float64	Rulbus::Real64
	the libraries' 64-bit real type.
typedef std::string	Rulbus::String
	the libraries' string type.
typedef std::exception	Rulbus::StdException
	the std::exception type.
typedef String	Rulbus::Name
	the Rulbus device name type.
typedef Int	Rulbus::Addr
	the Rulbus address type.
typedef Int	Rulbus::Rack
	the Rulbus rack number type.
typedef Real	Rulbus::Volt
	the voltage type.
typedef Real32	Rulbus::Volt32
	the 32-bit voltage type.
typedef Real	Rulbus::Time
	the time type.
typedef Real	Rulbus::Freq
	the frequency type.

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Define Documentation

#define DEBUG   DFLAG_NONE

DEBUG contains a bit-pattern that specifies which subjects must be included in the debugging: DFLAG_NONE include no debug subjects DFLAG_ALL include all debug subjects DFLAG_PRODUCTION include all but ensure debug subjects DFLAG_GENERAL debug subjects combined in one group DFLAG_INTERFACE report more details on Rulbus Interface errors DFLAG_BUSVIOLATION check for Rulbus address/data violations DFLAG_REQUIRE design-by-contract: require pre-condition. DFLAG_ENSURE design-by-contract: ensure post-condition. DFLAG_NEVER_GET_HERE design-by-contract: ensure never reached. Following Kernighan & Pike [1999], page 200, we use DEBUG in an if statement: if ( DEBUG & DFLAG_BUSVIOLATION ) // action... By using an if statement as opposed to a preprocessor #if line, the syntax of the debug code is also checked when the debug code is inactivated. If the (constant) condition evaluates to zero, the Borland C++ 5.6 compiler optimization process will change the test into an unconditional jump, so the debugging code incurs little execution overhead if not used. However the (unreachable) code for the if-statement is retained in the generated code. (Other compilers may remove the if-statement completely.) /* * debug.cpp - determine presence of debugging code. */ #define DFLAG_NONE 0x0000 #define DFLAG_GENERAL 0x0001 #define DEBUG DFLAG_NONE void debug( const char *msg ); int main() { if ( DEBUG & DFLAG_GENERAL ) { debug( "general debugging" ); } return 0; } Generates the following assembly code: .386p ifdef ??version if ??version GT 500H .mmx endif endif model flat ifndef ??version ?debug macro endm endif ?debug S "debug.cpp" ?debug T "debug.cpp" _TEXT segment dword public use32 'CODE' _TEXT ends _DATA segment dword public use32 'DATA' _DATA ends _BSS segment dword public use32 'BSS' _BSS ends DGROUP group _BSS,_DATA _TEXT segment dword public use32 'CODE' _main segment virtual @_main proc near ?live16385@0: ; ; int main() ; push ebp mov ebp,esp ; ; { ; if ( DEBUG & DFLAG_GENERAL ) ; @1: jmp short @2 ; ; { ; debug( "general debugging" ); ; push offset s@ call @@debug$qpxc pop ecx ; ; } ; ; return 0; ; @2: xor eax,eax ; ; } ; @4: @3: pop ebp ret @_main endp _main ends _TEXT ends _DATA segment dword public use32 'DATA' s@ label byte ; s@+0: db "general debugging",0 align 4 _DATA ends _TEXT segment dword public use32 'CODE' _TEXT ends @@debug$qpxc equ @debug$qpxc extrn @debug$qpxc:near ?debug D "debug.cpp" 12620 28747 end

#define DECLARE_CLASS (  tag   )

Value: class tag; \ typedef tag * tag ## Ptr; \ typedef const tag * tag ## Cptr; \ typedef tag & tag ## Ref; \ typedef const tag & tag ## Cref;

#define DECLARE_TYPE (  mydecl, mytype   )

Value: typedef mydecl mytype; \ typedef mytype * mytype ## Ptr; \ typedef const mytype * mytype ## Cptr; \ typedef mytype & mytype ## Ref; \ typedef const mytype & mytype ## Cref;

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