If I would be a virus writer, I would definitely open at least one db (virus
master copy:) with exclusive mode right after reset, thus making it
unreadable, (DmOpenDatabase will fail). Sure I would need to store the dbref
somewhere:).
I have seen some system databases also use the exclusive open mode.
The only way to read such databases is to perform a "no-notify" reset.
Best regards,
Miro Pomsar
----- Original Message -----
From: "Robert Moynihan" <[EMAIL PROTECTED]>
To: "Palm Developer Forum" <[email protected]>
Sent: Wednesday, April 13, 2005 01:22
Subject: Re: reading stored memory
> Scott Erickson wrote:
>
> >Bob,
> > Here is what I got at this point. Is this pretty much what I need to
do
> >to read through all dbs on the device?
> >
> >
>
> Here's a function that I use to build a list of databases in one of my
> apps. I haven't really typed this out all that well, but it should give
> some ideas.
>
> First I initialize the 2 variables, then call BuildDBList() with the
> type of db that I am looking for. Note that this ONLY looks for dbs
> created by my app, so the CreatorID is hardcoded as RPNAppID. Using
> NULL here would search for all creators. Once the list has been created
> in memory, it is really easy to refer to it; see the bit of code at the
> bottom.
>
> //these are globals that I can access from any part of my app
> MemHandle dbListH=NULL;
> UInt16 gLockCount=0;
>
> //this defines the structure for dbList
> typedef struct {
> UInt16 card;
> LocalID currentDB;
> UInt16 other;
> } myDbListType;
>
> //this function builds the list. I do this once, and only again when I
> detect that a change has been made.
> void BuildDBList(UInt32 type)
> //type could be NULL if you want to search for ALL types.
> {
> DmSearchStateType state;
> Boolean latestVer=false; //this is usually false for apps
> UInt16 card;
> LocalID currentDB=0;
> UInt16 attributesP;
> UInt16 count=0;
> UInt16 maxCount=10;
> Err Error;
> Char dbName[32];
> LocalID appInfoIDP;
> Char *ch=(void*)&type;
> myDbListType *dbListP;
>
> //initialize memory for dblist
> if (dbListH){
> MemHandleFree(dbListH);
> dbListH=NULL;
> }
> dbListH=MemHandleNew(maxCount*sizeof(myDbListType));
> dbListP=myMemHandleLock(dbListH);
>
> Error = DmGetNextDatabaseByTypeCreator(true, &state, type, RPNAppID,
> latestVer, &card, ¤tDB);
> //Build list of names
> while (!Error && currentDB && count<256) {
> Error = DmDatabaseInfo(card, currentDB,
> dbName,&attributesP,NULL,NULL,NULL,NULL,NULL,&appInfoIDP,NULL,NULL,NULL);
> if (StrNCompare(ch+1,dbName+4,3)==0){
> //grow the list if necessary
> if (count==maxCount){
> Err err;
> maxCount+=10;
> myMemPtrUnlock(dbListP);
>
err=MemHandleResize(dbListH,maxCount*sizeof(myDbListType));
> dbListP=myMemHandleLock(dbListH);
> if (err){
> maxCount-=10;
> break;
> }
> }
> //add entry to dbList
> dbListP[count].card=card;
> dbListP[count].currentDB=currentDB;
> if (type=='BPgm'){
> DmOpenRef db;
> UInt16 key;
> db=DmOpenDatabase(card,currentDB,dmModeReadOnly);
> GetProgHeader(db, NULL, &key, NULL);
> DmCloseDatabase(db);
> dbListP[count].other=key;
> }
> else
> dbListP[count].other=0;
> count++;
> }
> Error = DmGetNextDatabaseByTypeCreator(false, &state, type,
> RPNAppID, latestVer, &card, ¤tDB);
> }
> dbListCount=count;
> SysQSort (dbListP, count, sizeof(myDbListType), myCompareDBNames, 0);
> myMemPtrUnlock(dbListP);
> }
>
>
> The list is a list of card numbers and localIDs for databases. With
> this list in place it is easy to populate a popup list, for instance.
> If I wanted to find the name of the databases in my list I would do
> something like this...
> {
> myDbListType *dbListP;
> UInt16 dbIndex=index; //this is the index of the list
> member that I am interested in
> char name[32];
>
> dbListP=myMemHandleLock(dbListH);
> DmDatabaseInfo(dbListP[dbIndex].card,
> dbListP[dbIndex].currentDB,
> name,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL);
> myMemPtrUnlock(dbListP);
> }
>
> When you are done with the list just do MemHandleFree(dbListH) and set
> dbListCount to 0.
>
> Bob.
>
>
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