cyg_ass.h

该工程是从ecos嵌入式系统下移植过来的一个小型的fat16文件系统

#ifndef CYGONCE_INFRA_CYG_ASS_H
#define CYGONCE_INFRA_CYG_ASS_H

//==========================================================================
//
//      assert.h
//
//      Macros and prototypes for the assert system
//
//==========================================================================
//####ECOSGPLCOPYRIGHTBEGIN####
// -------------------------------------------
// This file is part of eCos, the Embedded Configurable Operating System.
// Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.
//
// eCos is free software; you can redistribute it and/or modify it under
// the terms of the GNU General Public License as published by the Free
// Software Foundation; either version 2 or (at your option) any later version.
//
// eCos is distributed in the hope that it will be useful, but WITHOUT ANY
// WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
// for more details.
//
// You should have received a copy of the GNU General Public License along
// with eCos; if not, write to the Free Software Foundation, Inc.,
// 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
//
// As a special exception, if other files instantiate templates or use macros
// or inline functions from this file, or you compile this file and link it
// with other works to produce a work based on this file, this file does not
// by itself cause the resulting work to be covered by the GNU General Public
// License. However the source code for this file must still be made available
// in accordance with section (3) of the GNU General Public License.
//
// This exception does not invalidate any other reasons why a work based on
// this file might be covered by the GNU General Public License.
//
// Alternative licenses for eCos may be arranged by contacting Red Hat, Inc.
// at http://sources.redhat.com/ecos/ecos-license/
// -------------------------------------------
//####ECOSGPLCOPYRIGHTEND####
//==========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s):   nickg from an original by hmt
// Contributors:        nickg
// Date:        1997-09-08
// Purpose:     Use asserts to avoid writing duff code.
// Description: Runtime tests that compile to nothing in
//              release versions of the code, to allow
//              as-you-go testing of alternate builds.
// Usage:       #include <cyg/infra/cyg_ass.h>
//              ...
//              CYG_ASSERT( pcount > 0, "Number of probes should be > 0!" );
//
//      which can result, for example, in a message of the form:
//      ASSERT FAILED: probemgr.cxx:1340, scan_probes() :
//                     number of probes should be > 0!
//      if the boolean "pcount > 0" is false.
//
//####DESCRIPTIONEND####
//
//==========================================================================


#include "cyg_type.h"         // for CYGBLD_ATTRIB_NORET

// -------------------------------------------------------------------------
// If we do not have a function name macro, define it ourselves

#ifndef CYGDBG_INFRA_DEBUG_FUNCTION_PSEUDOMACRO
                                        // __PRETTY_FUNCTION__ does not work
# ifndef __PRETTY_FUNCTION__            // And it is not already defined
#  define __PRETTY_FUNCTION__ NULL
# endif
#endif

// -------------------------------------------------------------------------
// This is executed to deal with failure - breakpoint it first!
// It is declared as a weak symbol to allow user code to override the
// definition.

externC void
cyg_assert_fail( const char* /* psz_func */, const char* /* psz_file */,
                 cyg_uint32 /* linenum */, const char* /* psz_msg */ )  __THROW
    CYGBLD_ATTRIB_NORET CYGBLD_ATTRIB_WEAK;

externC void
cyg_assert_msg( const char *psz_func, const char *psz_file,
                cyg_uint32 linenum, const char *psz_msg ) __THROW;

// -------------------------------------------------------------------------

#ifdef CYGDBG_USE_ASSERTS

// -------------------------------------------------------------------------
// We define macros and appropriate prototypes for the assert/fail
// system.  These are:
//      CYG_FAIL        - unconditional panic
//      CYG_ASSERT      - panic if boolean expression is false
//      CYG_ASSERTC     - compact version of CYG_ASSERT

# ifdef CYGDBG_INFRA_DEBUG_ASSERT_MESSAGE
#  define CYG_ASSERT_DOCALL( _msg_ )                                      \
        CYG_MACRO_START                                                   \
        /* Make sure we always get a pretty-printed message */            \
        cyg_assert_msg( __PRETTY_FUNCTION__, __FILE__, __LINE__, _msg_ ); \
        cyg_assert_fail( __PRETTY_FUNCTION__, __FILE__, __LINE__, _msg_ );\
        CYG_MACRO_END
# else
#   define CYG_ASSERT_DOCALL( _msg_ )    \
        CYG_MACRO_START                 \
        const char* _tmp1_ = _msg_;     \
        _tmp1_ = _tmp1_;                \
        cyg_assert_fail( __PRETTY_FUNCTION__, __FILE__, __LINE__, NULL ); \
        CYG_MACRO_END
# endif

// unconditional failure; use like panic(), coredump() &c.
# define CYG_FAIL( _msg_ )              \
        CYG_MACRO_START                 \
        CYG_ASSERT_DOCALL( _msg_ );      \
        CYG_MACRO_END

// conditioned assert; if the condition is false, fail.
# define CYG_ASSERT( _bool_, _msg_ )    \
        CYG_MACRO_START                 \
        if ( ! ( _bool_ ) )             \
            CYG_ASSERT_DOCALL( _msg_ );  \
        CYG_MACRO_END

# define CYG_ASSERTC( _bool_ )          \
       CYG_MACRO_START                  \
       if ( ! ( _bool_ ) )              \
           CYG_ASSERT_DOCALL( #_bool_ );\
       CYG_MACRO_END

#else // ! CYGDBG_USE_ASSERTS

// -------------------------------------------------------------------------
// No asserts: we define empty statements for assert & fail.

# define CYG_FAIL( _msg_ )           CYG_EMPTY_STATEMENT
# define CYG_ASSERT( _bool_, _msg_ ) CYG_EMPTY_STATEMENT
# define CYG_ASSERTC( _bool_ )       CYG_EMPTY_STATEMENT

#endif // ! CYGDBG_USE_ASSERTS

// -------------------------------------------------------------------------
// Pointer integrity checks.
// These check not only for NULL pointer, but can also check for pointers
// that are outside to defined memory areas of the platform or executable.
// We differentiate between data and function pointers, so that we can cope
// with different formats, and so we can check them against different memory
// regions.

externC cyg_bool cyg_check_data_ptr(const void *ptr);
externC cyg_bool cyg_check_func_ptr(const void (*ptr)(void));

#ifdef CYGDBG_USE_ASSERTS

# define CYG_CHECK_DATA_PTR( _ptr_, _msg_ )             \
        CYG_MACRO_START                                 \
        if( !cyg_check_data_ptr((const void *)(_ptr_)))       \
           CYG_ASSERT_DOCALL( _msg_ );                   \
        CYG_MACRO_END

# define CYG_CHECK_FUNC_PTR( _ptr_, _msg_ )             \
        CYG_MACRO_START                                 \
        if( !cyg_check_func_ptr((const void (*)(void))(_ptr_))) \
           CYG_ASSERT_DOCALL( _msg_ );                   \
        CYG_MACRO_END
        
# define CYG_CHECK_DATA_PTRC( _ptr_ )                   \
         CYG_MACRO_START                                \
         if ( !cyg_check_data_ptr((const void *)(_ptr_)))     \
             CYG_ASSERT_DOCALL("data pointer (" #_ptr_ ") is valid");\
         CYG_MACRO_END

# define CYG_CHECK_FUNC_PTRC( _ptr_ )                       \
         CYG_MACRO_START                                    \
         if ( !cyg_check_func_ptr((const void (*)(void))(_ptr_))) \
             CYG_ASSERT_DOCALL("function pointer (" #_ptr_ ") is valid"); \
         CYG_MACRO_END

#else // CYGDBG_USE_ASSERTS

# define CYG_CHECK_DATA_PTR( _ptr_, _msg_ ) CYG_EMPTY_STATEMENT
# define CYG_CHECK_FUNC_PTR( _ptr_, _msg_ ) CYG_EMPTY_STATEMENT
# define CYG_CHECK_DATA_PTRC( _ptr_ )       CYG_EMPTY_STATEMENT
# define CYG_CHECK_FUNC_PTRC( _ptr_ )       CYG_EMPTY_STATEMENT

#endif // CYGDBG_USE_ASSERTS
            
// -------------------------------------------------------------------------
// Unconditional definitions:

// Check an object for validity by calling its own checker.
// Usage:
//   ClassThing *p = &classobject;
//   CYG_ASSERTCLASS( p, "Object at p is broken!" );

// this enum gives some options as to how keenly to test; avoids cluttering
// the member function declaration if the implementor wants to do more
// zealous tests themselves.

enum cyg_assert_class_zeal {
  cyg_system_test       = -1,
  cyg_none              = 0,
  cyg_trivial,
  cyg_quick,
  cyg_thorough,
  cyg_extreme
};

// -------------------------------------------------------------------------
// Define macros for checking classes:
//
//      CYG_ASSERT_CLASS        - do proforma check on a class pointer
//      CYG_ASSERT_CLASSO       - do proforma check on a class object
//      CYG_ASSERT_ZERO_OR_CLASS- a class pointer is NULL or valid
//      CYG_ASSERT_THIS         - "this" is valid
//      + 3 compact variants and two aliases for backwards compatibility.
//
// All of these end up going via CYG_ASSERT(), which will be an empty
// statement if CYGDBG_USE_ASSERTS is disabled. There is no need to
// test CYGDBG_USE_ASSERTS again here.
//
// The idiom required is that a class have a member function called
// "bool check_this( cyg_assert_class_zeal ) const" that returns true
// iff the object is OK.  This need not be conditionally compiled against
// CYGDBG_USE_ASSERTS but it can be if only this macro is used to
// invoke it.  Alternatively it can be invoked by hand with other
// choices from the above enum.

// Assert the checker function of an object by pointer, or in hand.

#ifdef __cplusplus

# ifndef CYG_ASSERT_CLASS_ZEAL
#  define CYG_ASSERT_CLASS_ZEAL (cyg_quick) // can be redefined locally
# endif

# define CYG_ASSERT_CLASS( _pobj_, _msg_ ) \
    CYG_ASSERT( ((0 != (_pobj_)) &&        \
                 (_pobj_)->check_this( CYG_ASSERT_CLASS_ZEAL )), _msg_ )

# define CYG_ASSERTCLASS( _pobj_,_msg_) \
    CYG_ASSERT_CLASS( (_pobj_), _msg_ )

# define CYG_ASSERT_CLASSO( _obj_, _msg_ ) \
    CYG_ASSERT( (_obj_).check_this( CYG_ASSERT_CLASS_ZEAL ), _msg_ )

# define CYG_ASSERTCLASSO( _obj_, _msg_ ) \
    CYG_ASSERT_CLASSO( (_obj_), _msg_ )

# define CYG_ASSERT_ZERO_OR_CLASS( _pobj_, _msg_ ) \
    CYG_ASSERT( ((0 == (_pobj_)) ||                \
                 (_pobj_)->check_this( CYG_ASSERT_CLASS_ZEAL )), _msg_ )

# define CYG_ASSERT_THIS( _msg_ ) \
    CYG_ASSERT( this->check_this( CYG_ASSERT_CLASS_ZEAL ), _msg_ )

# define CYG_ASSERT_CLASSC( _pobj_ ) \
    CYG_ASSERT_CLASS( (_pobj_), "class pointer (" #_pobj_ ") is valid" )

# define CYG_ASSERT_CLASSOC( _obj_ ) \
    CYG_ASSERT_CLASSO( (_obj_), "object (" #_obj_ ") is valid" )

# define CYG_ASSERT_ZERO_OR_CLASSC( _pobj_ ) \
    CYG_ASSERT_ZERO_OR_CLASS((_pobj_),       \
        "class pointer (" #_pobj_ ") is zero or valid")

# define CYG_ASSERT_THISC( ) \
    CYG_ASSERT_THIS( "\"this\" pointer is valid" )
    
#define CYGDBG_DEFINE_CHECK_THIS \
    cyg_bool check_this( cyg_assert_class_zeal zeal ) const;

#endif // __cplusplus

// -------------------------------------------------------------------------
// Some alternative names for basic assertions that we can disable
// individually.
//
//      CYG_PRECONDITION        - argument checking etc
//      CYG_POSTCONDITION       - results etc
//      CYG_LOOP_INVARIANT      - for putting in loops
//
// C++ programmers have class-related variants of all of these.

#ifdef CYGDBG_INFRA_DEBUG_PRECONDITIONS
# define CYG_PRECONDITION( _bool_ , _msg_ ) CYG_ASSERT( _bool_, _msg_ )
# define CYG_PRECONDITIONC( _bool_ ) \
    CYG_ASSERT( _bool_, "precondition " #_bool_)
#else
# define CYG_PRECONDITION( _bool_ , _msg_ ) CYG_EMPTY_STATEMENT
# define CYG_PRECONDITIONC( _bool_ )        CYG_EMPTY_STATEMENT
#endif

#ifdef CYGDBG_INFRA_DEBUG_POSTCONDITIONS
# define CYG_POSTCONDITION( _bool_ , _msg_ ) CYG_ASSERT( _bool_, _msg_ )
# define CYG_POSTCONDITIONC( _bool_ ) \
    CYG_ASSERT( _bool_, "postcondition " #_bool_)
#else
# define CYG_POSTCONDITION( _bool_ , _msg_ ) CYG_EMPTY_STATEMENT
# define CYG_POSTCONDITIONC( _bool_ )        CYG_EMPTY_STATEMENT
#endif