filesys_8h.html

MP3 Player Source Code

       
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<p>
Start the filing system and initialize all necessary subsystems. 
<p>
Init storage and file system. FAT16 and FAT32 are supported 
<p>
Definition at line <a class="el" href="filesys_8c-source.html#l00923">923</a> of file <a class="el" href="filesys_8c-source.html">filesys.c</a>.
<p>
References <a class="el" href="unionAddress.html#o1">Address::b</a>, <a class="el" href="buffer_8h-source.html#l00131">Address::B::b0</a>, <a class="el" href="buffer_8h-source.html#l00132">Address::B::b1</a>, <a class="el" href="buffer_8h-source.html#l00133">Address::B::b2</a>, <a class="el" href="buffer_8h-source.html#l00134">Address::B::b3</a>, <a class="el" href="buffer_8h-source.html#l00107">DiskBlock::Raw::buf</a>, <a class="el" href="filesys_8c-source.html#l00029">dataStart</a>, <a class="el" href="buffer_8c-source.html#l00010">diskSect</a>, <a class="el" href="filesys_8c-source.html#l00806">FatInitGlobals()</a>, <a class="el" href="filesys_8c-source.html#l00021">fatStart</a>, <a class="el" href="filesys_8c-source.html#l00062">freeSector</a>, <a class="el" href="storage_8c-source.html#l00043">InitStorage()</a>, <a class="el" href="buffer_8h-source.html#l00129">Address::l</a>, <a class="el" href="board_8h-source.html#l00262">Public</a>, <a class="el" href="unionDiskBlock.html#o1">DiskBlock::raw</a>, <a class="el" href="storage_8c-source.html#l00110">ReadDiskSector()</a>, <a class="el" href="filesys_8c-source.html#l00024">rootStart</a>, and <a class="el" href="buffer_8c-source.html#l00015">sectorAddress</a>.
<p>
Referenced by <a class="el" href="player_8c-source.html#l00733">main()</a>.
<p>
<pre class="fragment"><div>00923                                      {
00924   <span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> c;
00925   
00926   <span class="comment">/* Initialize variables to sane values in case of error exit. */</span>
00927   <a class="code" href="filesys_8c.html#a2">fatStart</a> = 0;
00928   <a class="code" href="filesys_8c.html#a3">rootStart</a> = 0;
00929   <a class="code" href="filesys_8c.html#a4">dataStart</a> = 0;
00930   <a class="code" href="filesys_8c.html#a10">freeSector</a> = 0;
00931 
00932   ConsoleWrite(<span class="stringliteral">"Init: Filesystem; supports: MBR, FAT16, FAT32\r"</span>);
00933 
00934   ConsoleWrite(<span class="stringliteral">"Trying to bring up storage...\r"</span>);
00935   <span class="comment">/* Initialize the storage system */</span>
00936   <span class="keywordflow">if</span> ((c=<a class="code" href="storage_8c.html#a1">InitStorage</a>())){
00937     ConsoleWrite(<span class="stringliteral">"Storage init returns error "</span>);
00938     ConsolePutUInt(c);
00939     ConsolePutChar(13);
00940     <span class="keywordflow">return</span> c; <span class="comment">/* Error in InitStorage */</span>
00941   }
00942 
00943   ConsoleWrite(<span class="stringliteral">"Storage ok.\rSector 0 read..."</span>);
00944 
00945   <span class="comment">/* Load MBR */</span>
00946   <a class="code" href="buffer_8c.html#a2">sectorAddress</a>.<a class="code" href="unionAddress.html#o0">l</a> = 0; <span class="comment">/* the first sector on disk */</span>
00947   <a class="code" href="storage_8h.html#a2">ReadDiskSector</a>(0);
00948 
00949   ConsoleWrite(<span class="stringliteral">"ok.\rSector signature..."</span>);
00950   
00951   <span class="comment">/* Ok, it should be a MBR sector. Let's verify */</span>
00952   <span class="keywordflow">if</span> (<a class="code" href="buffer_8c.html#a0">diskSect</a>.<a class="code" href="unionDiskBlock.html#o1">raw</a>.<a class="code" href="structDiskBlock_1_1Raw.html#o0">buf</a>[510] != 0x55)
00953     <span class="keywordflow">return</span> 8; <span class="comment">/* sector 0 is not MBR. */</span>
00954   <span class="keywordflow">if</span> (<a class="code" href="buffer_8c.html#a0">diskSect</a>.<a class="code" href="unionDiskBlock.html#o1">raw</a>.<a class="code" href="structDiskBlock_1_1Raw.html#o0">buf</a>[511] != 0xaa)
00955     <span class="keywordflow">return</span> 8; <span class="comment">/* sector 0 is not MBR. */</span>
00956 
00957   ConsoleWrite(<span class="stringliteral">"ok.\rPartition 1..."</span>);
00958 
00959   <span class="comment">/* This checks that partition 1 is active. Alter code to allow</span>
00960 <span class="comment">   * other partition configurations. */</span>
00961   <span class="keywordflow">if</span> (<a class="code" href="buffer_8c.html#a0">diskSect</a>.<a class="code" href="unionDiskBlock.html#o1">raw</a>.<a class="code" href="structDiskBlock_1_1Raw.html#o0">buf</a>[0x1be] == 0x80){
00962     <a class="code" href="buffer_8c.html#a2">sectorAddress</a>.<a class="code" href="unionAddress.html#o1">b</a>.<a class="code" href="structAddress_1_1B.html#o0">b0</a> = <a class="code" href="buffer_8c.html#a0">diskSect</a>.<a class="code" href="unionDiskBlock.html#o1">raw</a>.<a class="code" href="structDiskBlock_1_1Raw.html#o0">buf</a>[0x1c6];
00963     <a class="code" href="buffer_8c.html#a2">sectorAddress</a>.<a class="code" href="unionAddress.html#o1">b</a>.<a class="code" href="structAddress_1_1B.html#o1">b1</a> = <a class="code" href="buffer_8c.html#a0">diskSect</a>.<a class="code" href="unionDiskBlock.html#o1">raw</a>.<a class="code" href="structDiskBlock_1_1Raw.html#o0">buf</a>[0x1c7];
00964     <a class="code" href="buffer_8c.html#a2">sectorAddress</a>.<a class="code" href="unionAddress.html#o1">b</a>.<a class="code" href="structAddress_1_1B.html#o2">b2</a> = <a class="code" href="buffer_8c.html#a0">diskSect</a>.<a class="code" href="unionDiskBlock.html#o1">raw</a>.<a class="code" href="structDiskBlock_1_1Raw.html#o0">buf</a>[0x1c8];
00965     <a class="code" href="buffer_8c.html#a2">sectorAddress</a>.<a class="code" href="unionAddress.html#o1">b</a>.<a class="code" href="structAddress_1_1B.html#o3">b3</a> = <a class="code" href="buffer_8c.html#a0">diskSect</a>.<a class="code" href="unionDiskBlock.html#o1">raw</a>.<a class="code" href="structDiskBlock_1_1Raw.html#o0">buf</a>[0x1c9];
00966     ConsoleWrite (<span class="stringliteral">" active"</span>);
00967   }<span class="keywordflow">else</span>{
00968     <span class="comment">//-------- DEBUG: Uncomment if you want to explore the sector</span>
00969     <span class="comment">//DumpDiskSector();</span>
00970     <span class="comment">//while (!KEY_BUTTON);</span>
00971     <a class="code" href="buffer_8c.html#a2">sectorAddress</a>.<a class="code" href="unionAddress.html#o1">b</a>.<a class="code" href="structAddress_1_1B.html#o0">b0</a> = <a class="code" href="buffer_8c.html#a0">diskSect</a>.<a class="code" href="unionDiskBlock.html#o1">raw</a>.<a class="code" href="structDiskBlock_1_1Raw.html#o0">buf</a>[0x1c6];
00972     <a class="code" href="buffer_8c.html#a2">sectorAddress</a>.<a class="code" href="unionAddress.html#o1">b</a>.<a class="code" href="structAddress_1_1B.html#o1">b1</a> = <a class="code" href="buffer_8c.html#a0">diskSect</a>.<a class="code" href="unionDiskBlock.html#o1">raw</a>.<a class="code" href="structDiskBlock_1_1Raw.html#o0">buf</a>[0x1c7];
00973     <a class="code" href="buffer_8c.html#a2">sectorAddress</a>.<a class="code" href="unionAddress.html#o1">b</a>.<a class="code" href="structAddress_1_1B.html#o2">b2</a> = <a class="code" href="buffer_8c.html#a0">diskSect</a>.<a class="code" href="unionDiskBlock.html#o1">raw</a>.<a class="code" href="structDiskBlock_1_1Raw.html#o0">buf</a>[0x1c8];
00974     <a class="code" href="buffer_8c.html#a2">sectorAddress</a>.<a class="code" href="unionAddress.html#o1">b</a>.<a class="code" href="structAddress_1_1B.html#o3">b3</a> = <a class="code" href="buffer_8c.html#a0">diskSect</a>.<a class="code" href="unionDiskBlock.html#o1">raw</a>.<a class="code" href="structDiskBlock_1_1Raw.html#o0">buf</a>[0x1c9];
00975 
00976 
00977   }
00978     
00979     <span class="comment">//    return 9; /* No active partition*/</span>
00980 
00981 
00982   ConsoleWrite(<span class="stringliteral">" at sector "</span>);
00983   ConsolePutHex8(<a class="code" href="buffer_8c.html#a2">sectorAddress</a>.<a class="code" href="unionAddress.html#o1">b</a>.<a class="code" href="structAddress_1_1B.html#o3">b3</a>);
00984   ConsolePutHex8(<a class="code" href="buffer_8c.html#a2">sectorAddress</a>.<a class="code" href="unionAddress.html#o1">b</a>.<a class="code" href="structAddress_1_1B.html#o2">b2</a>);
00985   ConsolePutHex8(<a class="code" href="buffer_8c.html#a2">sectorAddress</a>.<a class="code" href="unionAddress.html#o1">b</a>.<a class="code" href="structAddress_1_1B.html#o1">b1</a>);
00986   ConsolePutHex8(<a class="code" href="buffer_8c.html#a2">sectorAddress</a>.<a class="code" href="unionAddress.html#o1">b</a>.<a class="code" href="structAddress_1_1B.html#o0">b0</a>);
00987   ConsolePutChar(<span class="charliteral">'\r'</span>);
00988 
00989 
00990   <span class="comment">/* Now leave MBR and load sector 0 of partition */</span>
00991   <span class="comment">//SeekDiskSectorToRead();</span>
00992   <span class="comment">//ReadDiskSector(); /* to global buffer */</span>
00993   
00994   <a class="code" href="storage_8h.html#a2">ReadDiskSector</a>(<a class="code" href="buffer_8c.html#a2">sectorAddress</a>.<a class="code" href="unionAddress.html#o0">l</a>);
00995 
00996   <span class="keywordflow">if</span> (<a class="code" href="filesys_8c.html#a23">FatInitGlobals</a>()){
00997     <span class="keywordflow">return</span> 0x0a; <span class="comment">/* FAT init failed */</span>
00998   }
00999 
01000   <span class="keywordflow">return</span> 0; <span class="comment">/* All ok return */</span>
01001 
01002 }
</div></pre>
<p>
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<a class="anchor" name="a8" doxytag="filesys.h::OpenFile" ></a><p>
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          <td class="md" nowrap valign="top"> unsigned char OpenFile           </td>
          <td class="md" valign="top">(&nbsp;</td>
          <td class="md" nowrap valign="top">unsigned int&nbsp;</td>
          <td class="mdname1" valign="top" nowrap> <em>fileNumber</em>          </td>
          <td class="md" valign="top">&nbsp;)&nbsp;</td>
          <td class="md" nowrap></td>
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<p>
Open a file for reading. 
<p>
Prepares the Filing System to read a data file from the storage. Files are referred to by their numbers, not file names. This makes the system generic, not necessarily needing a complex file system such as FAT. The way to assign numbers to files is implementation dependent. Returns 0 when ok, error code otherwise. <dl compact><dt><b>Parameters:</b></dt><dd>
  <table border="0" cellspacing="2" cellpadding="0">
    <tr><td></td><td valign=top><em>fileNumber</em>&nbsp;</td><td>number of file, starting from beginning of storage, to open.</td></tr>
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