Mac-Source 1994 July/Mac-Source_July_1994.iso/C and C++/Entertainment/MacMud/Sockets/dnr.c

C/C++ Source or Header | 1993-03-17 | 4.6 KB | 210 lines | [TEXT/MPS ]

/*     DNR.c - DNR library for MPW

    (c) Copyright 1988 by Apple Computer.  All rights reserved

*/

#include <Resources.h>
#include <Files.h>
#include <OSUtils.h>
#include <Memory.h>
#include <Errors.h>
#include <Traps.h>
#include <GestaltEqu.h>
#include <Folders.h>
#include <ToolUtils.h>

#define OPENRESOLVER    1
#define CLOSERESOLVER    2
#define STRTOADDR        3
#define    ADDRTOSTR        4
#define    ENUMCACHE        5
#define ADDRTONAME        6

Handle codeHndl = nil;

typedef OSErr (*OSErrProcPtr)();
OSErrProcPtr dnr = nil;

TrapType GetTrapType(theTrap)
unsigned long theTrap;
{
    if (BitAnd(theTrap, 0x0800) > 0)
        return(ToolTrap);
    else
        return(OSTrap);
}

Boolean TrapAvailable1(trap)
unsigned long trap;
{
    TrapType trapType = ToolTrap;
    unsigned long numToolBoxTraps;

    if (NGetTrapAddress(_InitGraf, ToolTrap) == NGetTrapAddress(0xAA6E, ToolTrap))
        numToolBoxTraps = 0x200;
    else
        numToolBoxTraps = 0x400;

    trapType = GetTrapType(trap);
    if (trapType = ToolTrap) {
        trap = BitAnd(trap, 0x07FF);
        if (trap > numToolBoxTraps)
            trap = _Unimplemented;
    }
    return(NGetTrapAddress(trap, trapType) != NGetTrapAddress(_Unimplemented, ToolTrap));
}

short GetCPanelFolder()
{
    short vRefNum = 0;
    long dirID = 0;
    SysEnvRec info;
    Boolean hasFolderMgr, hasGestalt = false;
    long feature;
    short wdRef;

    dirID = 0;
    if (TrapAvailable1(_Gestalt)) if (Gestalt(gestaltFindFolderAttr, &feature) == noErr) hasFolderMgr = true;
    if (!hasFolderMgr) {
        SysEnvirons(1, &info);
        return(info.sysVRefNum);
    }
    else {
        if (FindFolder(kOnSystemDisk, kControlPanelFolderType, kDontCreateFolder, &vRefNum, &dirID) != noErr) return(0);
        if (OpenWD(vRefNum, dirID, 'dnrp', &wdRef) == noErr)
            return(wdRef);
        else
            return(0);
    }
}

/* OpenOurRF is called to open the MacTCP driver resources */

short OpenOurRF()
{
    ParamBlockRec fi;
    Str255 filename;
    short vRefNum;

    vRefNum = GetCPanelFolder();
    fi.fileParam.ioCompletion = nil;
    fi.fileParam.ioNamePtr = &filename;
    fi.fileParam.ioVRefNum = vRefNum;
    fi.fileParam.ioFDirIndex = 1;

    while (PBGetFInfo(&fi, false) == noErr) {
        /* scan system folder for driver resource files of specific type & creator */
        if (fi.fileParam.ioFlFndrInfo.fdType == 'cdev' &&
            fi.fileParam.ioFlFndrInfo.fdCreator == 'ztcp') {
            /* found the MacTCP driver file */
            return(OpenRFPerm(&filename, vRefNum, fsRdPerm));
        }
        /* check next file in system folder */
        fi.fileParam.ioFDirIndex++;
    }
    return(-1);
}

OSErr OpenResolver(fileName)
char *fileName;
{
    short refnum;
    OSErr rc;
    long feature = 0;
    Boolean hasTimeMgr = false;

    if (dnr != nil)
        /* resolver already loaded in */
        return(noErr);

    /* open the MacTCP driver to get DNR resources. Search for it based on
       creator & type rather than simply file name */
    refnum = OpenOurRF();

    /* ignore failures since the resource may have been installed in the
       System file if running on a Mac 512Ke */

    /* load in the DNR resource package */
    codeHndl = GetIndResource('dnrp', 1);

    if (codeHndl == nil) {
        /* can't open DNR */
        return(ResError());
    }

    DetachResource(codeHndl);
    if (refnum != -1) {
        CloseWD(refnum);
        CloseResFile(refnum);
    }

    /* lock the DNR resource since it cannot be reloated while opened */
    HLock(codeHndl);
    dnr = (OSErrProcPtr) *codeHndl;

    /* call open resolver */
    rc = (*dnr)(OPENRESOLVER, fileName);
    if (rc != noErr) {
        /* problem with open resolver, flush it */
        HUnlock(codeHndl);
        DisposHandle(codeHndl);
        dnr = nil;
    }

    /* check is the extended time manager is available */
    if (TrapAvailable1(_Gestalt)) if (Gestalt(gestaltTimeMgrVersion, &feature) == noErr) hasTimeMgr = true;
    if (hasTimeMgr) {
        if ((feature == gestaltExtendedTimeMgr) || (feature == gestaltRevisedTimeMgr))
            rc == noErr;
        else rc == 1;
    }

    return(rc);
}

OSErr CloseResolver()
{
    if (dnr == nil)
        /* resolver not loaded error */
        return(notOpenErr);

    /* call close resolver */
    (void) (*dnr)(CLOSERESOLVER);

    /* release the DNR resource package */
    HUnlock(codeHndl);
    DisposHandle(codeHndl);
    dnr = nil;
    return(noErr);
}

OSErr StrToAddr(hostName, rtnStruct, resultproc, userDataPtr)
char *hostName;
struct hostInfo *rtnStruct;
long resultproc;
char *userDataPtr;
{
    return((*dnr)(STRTOADDR, hostName, rtnStruct, resultproc, userDataPtr));
}

void AddrToStr(addr, addrStr)
unsigned long addr;
char *addrStr;
{
    (*dnr)(ADDRTOSTR, addr, addrStr);
}

OSErr AddrToName(addr, rtnStruct, resultproc, userDataPtr)
unsigned long addr;
struct hostInfo *rtnStruct;
long resultproc;
char *userDataPtr;
{
    if (dnr == nil)
        /* resolver not loaded error */
        return(notOpenErr);

    return((*dnr)(ADDRTONAME, addr, rtnStruct, resultproc, userDataPtr));
}