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Subject: Re: Bug/glitch in Nalimov Code (and in Wilhelm)?

Author: Robert Hyatt

Date: 10:57:03 05/10/04

Go up one level in this thread


On May 09, 2004 at 22:23:47, Eugene Nalimov wrote:

>On May 09, 2004 at 03:58:05, Dieter Buerssner wrote:
>
>>I tried to update to newer Nalimov code (with support of the split TBs). Seemed
>>all easy, but then the program crashed. I had downloaded krppkr and kqppkq to
>>test. For some reason, I forgot to download the kqqpkq.0.nbb/nbw.emd files.
>>After the crash, I tried to check integrity with Wilhelm. It did not complain
>>about the missing files - just said installed/integer.
>>
>>In the actual Nalimov code, one error condition seems to be missing.
>>
>>/* Probe TB - lower level (not exportable) function */
>>
>>static int TB_FASTCALL TbtProbeTable(int iTb, color side, unsigned indChunk,
>>                                     unsigned indInChunk)
>>{
>>  [...]
>>  /* Now read it from the disk */
>>  FILE     *fp;
>>  size_t    cb;
>>
>>/* First, check: is necessary file opened?
>>   As files are not thread-safe, lock file */
>>  Lock(ptbd->m_rglockFiles[side]);
>>  if (ptbd->m_fSplit) {
>>    iExtent = indChunk >> (31 - LOG2_TB_CB_CACHE_CHUNK);
>>    iPhysicalChunk = indChunk - (iExtent << (31 - LOG2_TB_CB_CACHE_CHUNK));
>>  } else {
>>    iExtent = 0;
>>    iPhysicalChunk = indChunk;
>>  }
>>  fp = ptbd->m_rgfpFiles[side][iExtent];
>>  if (NULL == fp) {
>>/* Not - try to open it */
>>    pszFileName = ptbd->m_rgpchFileName[side][iExtent];
>>    if (NULL != pszFileName) {
>>    [carefully tries to open the file with all sort of error checks]
>>    }
>>
>>    [But an else case is missing, and later code assumes, that fp is initialized
>>correctly. At least this is my understanding of the code. ]
>>  }
>>  [Now using fp, which might be NULL]
>>
>>Regards,
>>Dieter
>
>Add "else goto ERROR_LABEL;". I believe that is enough.
>
>Will add it to the new code I Bob will release soon.
>
>Thanks,
>Eugene


I added it to the code I have already...

Bob




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