Prob reading uint32 from db

[Ray Marron]

I added a UInt32 value in my Palm app's database to act as a timestamp that
gets its value from TimGetSeconds() just before the record is saved.  When I
read this value back out, it is always a much smaller value.  I'm sure I'm
messing it up during the save or retrieval.  Can somebody take a look at my
code and see if you can notice anything I'm doing wrong?  This is my first
Palm app, and most of my save/load code was taken from CW and book examples.
If there is some code you would like to see that I haven't included, just
request it.

For example, if I save a record with a timestamp of 3128320727 (the morning
of 2003-02-17), it gets read back as 1985899456 (sometime in 1966!).  There
doesn't seem to be a constant difference between the saved/read values, but
the difference is always ~1.141 billion.

Pasted from my app's header file:

typedef struct FuelsDBType
{
 char ttype;
 UInt32 seconds;  // Timestamp
 char tailno[9];
 char amount[11];
} FuelsDBType;

typedef FuelsDBType* FuelsDBPtr;

#define FDB_TTYPE_START    0
#define FDB_TTYPE_SIZE     sizeof(char)
#define FDB_SECONDS_START  (FDB_TTYPE_START + FDB_TTYPE_SIZE)
#define FDB_SECONDS_SIZE   sizeof(UInt32)
#define FDB_TAILNO_START   (FDB_SECONDS_START + FDB_SECONDS_SIZE)
#define FDB_TAILNO_SIZE    9
#define FDB_AMOUNT_START   (FDB_TAILNO_START + FDB_TAILNO_SIZE)
#define FDB_AMOUNT_SIZE    11

#define FDB_RECSIZE     (FDB_AMOUNT_START + FDB_AMOUNT_SIZE)

The seconds value was formerly at the end of the struct. I moved it up
behind ttype in case my string saving was buggy but it didn't change
anything.

>From my app's database.c:

Err AddToDatabase(FuelsDBPtr recordP)
{
 Err error = errNone;
 UInt16 recIndex = dmMaxRecordIndex;
 MemHandle recH;
 MemPtr recP;

 recH = DmNewRecord(gDB, &recIndex, FDB_RECSIZE);
 if (recH) {
  recP = MemHandleLock(recH);
  DmWrite(recP, FDB_TTYPE_START, &recordP->ttype,
          FDB_TTYPE_SIZE);
  DmWrite(recP, FDB_SECONDS_START, &recordP->seconds,
          FDB_SECONDS_SIZE);
  DmWrite(recP, FDB_TAILNO_START, recordP->tailno,
          FDB_TAILNO_SIZE);
  DmWrite(recP, FDB_AMOUNT_START, recordP->amount,
          FDB_AMOUNT_SIZE);
  error = DmReleaseRecord(gDB, recIndex, true);
  MemHandleUnlock(recH);
 }

 if (error == errNone)
  return 0;
 else
  return DmGetLastErr();
}


Err GetFromDatabase(FuelsDBPtr recordP, UInt32 cursor)
{
    MemHandle recH;
    FuelsDBPtr recP;
    Err error = 0;

    recH = DmQueryRecord(gDB, cursor);
    if (recH)
    {
        recP = (FuelsDBPtr)MemHandleLock(recH);
        recordP->ttype = recP->ttype;
        recordP->seconds = recP->seconds;
        StrCopy(recordP->tailno, recP->tailno);
        StrCopy(recordP->amount, recP->amount);
        MemHandleUnlock(recH);
    }
    else
     error = DmGetLastErr();
    return error;
}

Thanks for your help!

--
Ray Marron



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