ASSERTS.CPP

//-------------------------------------------------------------------- 
// Microsoft OLE DB Sample Provider 
// (C) Copyright 1994 - 1996 Microsoft Corporation.  All Rights Reserved. 
// 
// @doc 
// 
// @module ASSERTS.CPP | Simple Assertion Routines 
// 
// 
#include "headers.h" 
#include <time.h> 
#include "asserts.h" 
 
#ifdef DEBUG    // only compile for debug! 
 
//-------------------------------------------------------------------- 
// @func Variable argument formatter and Dump routine for messages 
// 
// @rdesc NONE 
// 
void OLEDB_Trace 
    ( 
    const char *format,     //@parm IN | Format String 
    ...                     //@parm IN | Variable Arg List 
    ) 
{ 
    char buff[300 ]; 
    int cBytesWritten; 
    va_list argptr; 
 
    // If this overflows, it will wipe out the return stack. 
    // However, we have a wonderful version that ensures no overwrite. 
    // Nice because we can't do anything about errors here. 
 
    va_start( argptr, format ); 
    cBytesWritten = _vsnprintf( buff, sizeof( buff ), format, argptr ); 
    va_end( argptr ); 
 
    // assert would report overflow first, recursively, but don't bother. 
    // Would be OK, since this assert could be proven 
    // not to overflow temp buffer in assert. 
    //assert( cBytesWritten < sizeof(buff) ); 
 
    OutputDebugString( buff ); 
} 
 
//-------------------------------------------------------------------- 
// @func This an internal assertion routine that dumps more information 
// than the normal assertion routines.. 
// 
// @rdesc NONE 
// 
void OLEDB_Assert 
    ( 
    LPSTR expression,   //@parm IN | Expression to assert on 
    LPSTR filename,     //@parm IN | Filname where assertion occurred 
    long linenum        //@parm IN | Line number where assertion occurred 
    ) 
{ 
    char          szbuff[350 ]; 
    int           cBytesWritten; 
    volatile int  fAbort; 
 
    // If this overflows, it will wipe out the return stack. 
    // However, we have a wonderful version that ensures no overwrite. 
    // Good thing, because we can't do much about overflows here anyway. 
    // (However, use of "%.nns" works well.) 
 
    cBytesWritten = _snprintf( szbuff, sizeof( szbuff ), 
        "Assertion error!\n  File '%.50s', line '%ld'\n  Expression '%.200s'\n", 
        filename, linenum, expression ); 
 
    TRACE( szbuff ); 
 
    // We're a DLL (therefore Windows), so may not have an output stream we can write to. 
    ::MessageBox( 
        NULL,   // HWND, which we don't have 
        szbuff, // Text 
        "Assertion Error",  // Title 
        MB_SYSTEMMODAL | MB_ICONHAND | MB_OK ); 
 
    // Break and let the user get a crack at it. 
    // You can set fAbort=0 to continue merrily along. 
    fAbort = 1; 
    if (fAbort)  
        { 
        abort();    // Raises SIGABRT 
        } 
} 
#endif