www.pudn.com > snmp.rar > mem.c

/*++ 
 
Copyright (c) 1992-1997  Microsoft Corporation 
 
Module Name: 
 
    mem.c 
 
Abstract: 
 
    Contains memory allocation routines. 
 
        SnmpUtilMemAlloc 
        SnmpUtilMemReAlloc 
        SnmpUtilMemFree 
 
Environment: 
 
    User Mode - Win32 
 
Revision History: 
 
--*/ 
 
/////////////////////////////////////////////////////////////////////////////// 
//                                                                           // 
// Include files                                                             // 
//                                                                           // 
/////////////////////////////////////////////////////////////////////////////// 
 
#include  
#include  
 
 
/////////////////////////////////////////////////////////////////////////////// 
//                                                                           // 
// Global Variables                                                          // 
//                                                                           // 
/////////////////////////////////////////////////////////////////////////////// 
 
UINT g_nBytesTotal = 0; 
 
 
/////////////////////////////////////////////////////////////////////////////// 
//                                                                           // 
// Public Procedures                                                         // 
//                                                                           // 
/////////////////////////////////////////////////////////////////////////////// 
 
VOID 
SNMP_FUNC_TYPE 
SnmpUtilMemFree( 
    LPVOID pMem 
    ) 
 
/*++ 
 
Routine Description: 
 
    Releases memory used by SNMP entities. 
 
Arguments: 
 
    pMem - pointer to memory to release. 
 
Return Values: 
 
    None. 
 
--*/ 
 
{ 
    // validate 
    if (pMem != NULL) { 
 
#if defined(DBG) && defined(_SNMPDLL_) 
 
        // substract memory from global count 
        g_nBytesTotal -= (UINT)GlobalSize((HGLOBAL)pMem); 
 
        SNMPDBG(( 
            SNMP_LOG_VERBOSE, 
            "SNMP: MEM: releasing 0x%08lx (%d bytes, %d total).\n", 
            pMem, GlobalSize((HGLOBAL)pMem), g_nBytesTotal 
            )); 
 
#endif 
 
        // release memory 
        GlobalFree((HGLOBAL)pMem); 
    } 
} 
 
 
LPVOID 
SNMP_FUNC_TYPE 
SnmpUtilMemAlloc( 
    UINT nBytes 
    ) 
 
/*++ 
 
Routine Description: 
 
    Allocates memory used by SNMP entities. 
 
Arguments: 
 
    nBytes - number of bytes to allocate. 
 
Return Values: 
 
    Returns pointer to memory. 
 
--*/ 
 
{ 
    LPVOID pMem; 
 
    // attempt to allocate memory from process heap 
    pMem = GlobalAlloc(GMEM_FIXED|GMEM_ZEROINIT, (DWORD)nBytes); 
 
#if defined(DBG) && defined(_SNMPDLL_) 
 
    // add allocated memory to global count if successful 
    g_nBytesTotal += (UINT)((pMem != NULL) ? GlobalSize((HGLOBAL)pMem) : 0); 
 
    SNMPDBG(( 
        SNMP_LOG_VERBOSE, 
        "SNMP: MEM: allocated 0x%08lx (%d bytes, %d total).\n", 
        pMem, (pMem != NULL) ? GlobalSize((HGLOBAL)pMem) : 0, g_nBytesTotal 
        )); 
 
#endif 
 
    return pMem; 
} 
 
 
LPVOID 
SNMP_FUNC_TYPE 
SnmpUtilMemReAlloc( 
    LPVOID pMem, 
    UINT   nBytes 
    ) 
 
/*++ 
 
Routine Description: 
 
    Reallocates memory used by SNMP entities. 
 
Arguments: 
 
    pMem - pointer to memory to reallocate. 
 
    nBytes - number of bytes to allocate. 
 
Return Values: 
 
    Returns pointer to memory. 
 
--*/ 
 
{ 
    LPVOID pNew; 
 
    // validate 
    if (pMem == NULL) { 
 
        // forward to alloc routine 
        pNew = SnmpUtilMemAlloc(nBytes); 
 
    } else { 
 
#if defined(DBG) && defined(_SNMPDLL_) 
 
        SNMPDBG(( 
            SNMP_LOG_VERBOSE, 
            "SNMP: MEM: expanding 0x%08lx (%d bytes) to %d bytes.\n", 
            pMem, GlobalSize((HGLOBAL)pMem), nBytes 
            )); 
 
        // substract current memory from total 
        g_nBytesTotal -= (UINT)GlobalSize((HGLOBAL)pMem); 
 
#endif 
 
        // reallocate memory 
        pNew = GlobalReAlloc( 
                    (HGLOBAL)pMem, 
                    (DWORD)nBytes, 
                    GMEM_MOVEABLE | 
                    GMEM_ZEROINIT 
                    ); 
 
#if defined(DBG) && defined(_SNMPDLL_) 
 
        // add new memory to total count 
        g_nBytesTotal += (UINT)((pNew != NULL) ? GlobalSize((HGLOBAL)pNew) : 0); 
 
        SNMPDBG(( 
            SNMP_LOG_VERBOSE, 
            "SNMP: MEM: allocated 0x%08lx (%d bytes, %d total).\n", 
            pNew, (pNew != NULL) ? GlobalSize((HGLOBAL)pNew) : 0, g_nBytesTotal 
            )); 
 
#endif 
 
    } 
 
    return pNew; 
}