fat_8c-source.html

方便飞利浦arm7tdmi 处理器lpc2100开发的C函数库 Procyon ARMlib-LPC2100 C-Language Function Library for Philips LPC21

00324                     <span class="keywordflow">if</span>(entrycount == entry)     
00325                     {
00326                         <span class="comment">// desired entry has been found, break out</span>
00327                         gotEntry = 1;
00328                         <span class="keywordflow">break</span>;
00329                     }
00330                     <span class="comment">// otherwise</span>
00331                     entrycount++;           <span class="comment">// increment entry counter      </span>
00332                 }
00333             }
00334         }
00335         <span class="comment">// next directory entry</span>
00336         de++;
00337         <span class="comment">// next index</span>
00338         index++;
00339     }
00340     
00341     <span class="comment">// we have a file/dir to return</span>
00342     <span class="comment">// store file/dir starting cluster (start of data)</span>
00343     FileInfo.StartCluster = (<span class="keywordtype">unsigned</span> <span class="keywordtype">long</span>) ((<span class="keywordtype">unsigned</span> <span class="keywordtype">long</span>)de-&gt;deHighClust &lt;&lt; 16) + de-&gt;deStartCluster;
00344     <span class="comment">// store file/dir size</span>
00345     <span class="comment">// (note: size field for subdirectory entries is always zero)</span>
00346     FileInfo.Size = de-&gt;deFileSize;
00347     <span class="comment">// store file/dir attributes</span>
00348     FileInfo.Attr = de-&gt;deAttributes;
00349     <span class="comment">// store file/dir creation time</span>
00350     FileInfo.CreateTime = de-&gt;deCTime[0] | de-&gt;deCTime[1]&lt;&lt;8;
00351     <span class="comment">// store file/dir creation date</span>
00352     FileInfo.CreateTime = de-&gt;deCDate[0] | de-&gt;deCDate[1]&lt;&lt;8;
00353 
00354     <span class="keywordflow">return</span> gotEntry;
00355 }
00356 
00357 <span class="comment"></span>
00358 <span class="comment">///////////////////////////////////////////////////////////////////////////////////</span>
00359 <span class="comment"></span><span class="comment">/*</span>
00360 <span class="comment">    index = 16; // crank it up</span>
00361 <span class="comment">    do </span>
00362 <span class="comment">    {</span>
00363 <span class="comment">        if(index == 16) // time for next sector ?</span>
00364 <span class="comment">        {</span>
00365 <span class="comment">            ataReadSectors( DRIVE0, sector++, 1, SectorBuffer);</span>
00366 <span class="comment">            de = (struct direntry *) SectorBuffer;</span>
00367 <span class="comment">            index = 0;</span>
00368 <span class="comment">        }</span>
00369 <span class="comment">        </span>
00370 <span class="comment">        // check if this is a deleted entry slot</span>
00371 <span class="comment">        if(de-&gt;deName[0] != 0xE5)</span>
00372 <span class="comment">        {</span>
00373 <span class="comment">            // a valid entry</span>
00374 <span class="comment">            // is it a part of a long file/dir name?</span>
00375 <span class="comment">            if(de-&gt;deAttributes == ATTR_LONG_FILENAME)</span>
00376 <span class="comment">            {</span>
00377 <span class="comment">                // we have a long name entry</span>
00378 <span class="comment">                // cast this directory entry as a "windows" (LFN: LongFileName) entry</span>
00379 <span class="comment">                we = (struct winentry *) de;</span>
00380 <span class="comment">                </span>
00381 <span class="comment">                b = WIN_ENTRY_CHARS*( (we-&gt;weCnt-1) &amp; 0x0f);        // index into string</span>
00382 <span class="comment">                fnbPtr = &amp;FileNameBuffer[b];</span>
00383 <span class="comment">                for (i=0;i&lt;5;i++)   *fnbPtr++ = we-&gt;wePart1[i*2];   // copy first part</span>
00384 <span class="comment">                for (i=0;i&lt;6;i++)   *fnbPtr++ = we-&gt;wePart2[i*2];   // second part</span>
00385 <span class="comment">                for (i=0;i&lt;2;i++)   *fnbPtr++ = we-&gt;wePart3[i*2];   // and third part</span>
00386 <span class="comment">                if (we-&gt;weCnt &amp; 0x40) *fnbPtr = 0;                  // in case dirnamelength is multiple of 13</span>
00387 <span class="comment">                if ((we-&gt;weCnt &amp; 0x0f) == 1) hasBuffer = 1;     // mark that we have a long entry</span>
00388 <span class="comment">            }</span>
00389 <span class="comment">            else</span>
00390 <span class="comment">            {</span>
00391 <span class="comment">                // we have a short name entry</span>
00392 <span class="comment">                </span>
00393 <span class="comment">                // check if this is the end of a multi-part long name entry</span>
00394 <span class="comment">                if(hasBuffer)</span>
00395 <span class="comment">                {</span>
00396 <span class="comment">                    // a long entry name has been collected</span>
00397 <span class="comment">                    if(entrycount == entry)     </span>
00398 <span class="comment">                    {</span>
00399 <span class="comment">                        // desired entry has been found, break out</span>
00400 <span class="comment">                        break;</span>
00401 <span class="comment">                    }</span>
00402 <span class="comment">                    </span>
00403 <span class="comment">                    hasBuffer = 0;  // clear buffer </span>
00404 <span class="comment">                    entrycount++;   // increment entry counter      </span>
00405 <span class="comment">                }</span>
00406 <span class="comment">                else</span>
00407 <span class="comment">                {</span>
00408 <span class="comment">                    // entry is a short name (8.3 format)</span>
00409 <span class="comment">                    fnbPtr = FileNameBuffer;</span>
00410 <span class="comment">                    for (i=0;i&lt;8;i++)   *fnbPtr++ = de-&gt;deName[i];      // copy name</span>
00411 <span class="comment">                    *fnbPtr++ = '.';                                    // insert '.'</span>
00412 <span class="comment">                    for (i=0;i&lt;3;i++)   *fnbPtr++ = de-&gt;deExtension[i]; // copy extension</span>
00413 <span class="comment">                    *fnbPtr = 0;                                        // null-terminate</span>
00414 <span class="comment"></span>
00415 <span class="comment">                    if(entrycount == entry)     </span>
00416 <span class="comment">                    {</span>
00417 <span class="comment">                        // desired entry has been found, break out</span>
00418 <span class="comment">                        hasBuffer = 1;</span>
00419 <span class="comment">                        break;</span>
00420 <span class="comment">                    }</span>
00421 <span class="comment">                    entrycount++;   // increment entry counter      </span>
00422 <span class="comment">                }</span>
00423 <span class="comment">            }</span>
00424 <span class="comment">        }</span>
00425 <span class="comment">        // next directory entry</span>
00426 <span class="comment">        de++;</span>
00427 <span class="comment">        // next index</span>
00428 <span class="comment">        index++;</span>
00429 <span class="comment">    } while (*(de-&gt;deName) || index == 16); // 0 in de-&gt;deName[0] if no more entries</span>
00430 <span class="comment">*/</span>
00431 <span class="comment"></span>
00432 <span class="comment">///////////////////////////////////////////////////////////////////////////////////</span>
00433 <span class="comment"></span>
00434                     <span class="comment">// is it a directory ?</span>
00435 <span class="comment">/*                  if(de-&gt;deAttributes == ATTR_DIRECTORY)</span>
00436 <span class="comment">                    {</span>
00437 <span class="comment">                        unsigned long save = FirstDirCluster;</span>
00438 <span class="comment">                        unsigned int save2 = baseentry;</span>
00439 <span class="comment">                        unsigned long rval;</span>
00440 <span class="comment">                        </span>
00441 <span class="comment">                        strcpy(DirNameBuffer,FileNameBuffer);</span>
00442 <span class="comment">                        strcat(DirNameBuffer,"/");</span>
00443 <span class="comment"></span>
00444 <span class="comment">//                      rprintfStr(FileNameBuffer); rprintfStr("/"); //EOL();</span>
00445 <span class="comment"></span>
00446 <span class="comment">                        // call recursively</span>
00447 <span class="comment">                        FirstDirCluster = ((unsigned long)de-&gt;deHighClust &lt;&lt; 16) + de-&gt;deStartCluster;</span>
00448 <span class="comment">                        rval = fatGetDirEntry(entry,1);</span>
00449 <span class="comment">                        FirstDirCluster = save;</span>
00450 <span class="comment">                        baseentry = save2;</span>
00451 <span class="comment">                        if (rval)</span>
00452 <span class="comment">                            return rval;</span>
00453 <span class="comment">                        else    </span>
00454 <span class="comment">                        {</span>
00455 <span class="comment">                            // reload original sector</span>
00456 <span class="comment">                            ataReadSectors( DRIVE0, sector-1, 1, SectorBuffer);</span>
00457 <span class="comment">                            entrycount--;           // decrement entry counter      </span>
00458 <span class="comment">                            *DirNameBuffer = 0;</span>
00459 <span class="comment">                        }</span>
00460 <span class="comment">                    }</span>
00461 <span class="comment">                    else // normal file entry</span>
00462 <span class="comment">*/</span><span class="comment"></span>
00463 <span class="comment">//////////////////////////////////////////////////////////////////////////////////</span>
00464 <span class="comment"></span>
00465 <span class="comment">// change directory into </span>
00466 <span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> fatChangeDirectory(<span class="keywordtype">unsigned</span> <span class="keywordtype">short</span> entry)
00467 {
00468     <span class="comment">// get the requested directory entry</span>
00469     <span class="keywordflow">if</span>( fatGetDirEntry(entry) )
00470     {
00471         <span class="comment">// make sure the entry is a directory</span>
00472         <span class="keywordflow">if</span>(FileInfo.Attr &amp; ATTR_DIRECTORY)
00473         {
00474             <span class="comment">// change directories into this directory</span>
00475             <span class="comment">// check to see if we are changing back to root directory</span>
00476             <span class="keywordflow">if</span>(FileInfo.StartCluster)
00477             {
00478                 <span class="comment">// standard change directory</span>
00479                 CurrentDirStartCluster = FileInfo.StartCluster;
00480             }
00481             <span class="keywordflow">else</span>
00482             {
00483                 <span class="comment">// if startCluster pointer is zero,</span>
00484                 <span class="comment">// a change to the root directory is intended</span>
00485                 <span class="comment">// change directory to root</span>
00486                 CurrentDirStartCluster = RootDirStartCluster;
00487             }
00488             <span class="comment">// TODO: handle pathname properly for going up a directory</span>