os/kernelhwsrv/userlibandfileserver/fileserver/sfat/fat_config.cpp
author sl@SLION-WIN7.fritz.box
Fri, 15 Jun 2012 03:10:57 +0200
changeset 0 bde4ae8d615e
permissions -rw-r--r--
First public contribution.
     1 // Copyright (c) 1996-2009 Nokia Corporation and/or its subsidiary(-ies).
     2 // All rights reserved.
     3 // This component and the accompanying materials are made available
     4 // under the terms of the License "Eclipse Public License v1.0"
     5 // which accompanies this distribution, and is available
     6 // at the URL "http://www.eclipse.org/legal/epl-v10.html".
     7 //
     8 // Initial Contributors:
     9 // Nokia Corporation - initial contribution.
    10 //
    11 // Contributors:
    12 //
    13 // Description:
    14 // f32\sfat\fat_config.cpp
    15 // Implementation of the class that reads FAT filesystem configuration parameters from the estart.txt file, 
    16 // caches and provides access to them
    17 // 
    18 //
    19 
    20 /**
    21  @file
    22 */
    23 
    24 //!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    25 //!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    26 //!!
    27 //!! WARNING!! DO NOT edit this file !! '\sfat' component is obsolete and is not being used. '\sfat32'replaces it
    28 //!!
    29 //!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    30 //!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    31 
    32 #include <f32fsys.h>
    33 
    34 #include "common_constants.h"
    35 #include "sl_std.h"
    36 #include "fat_config.h"
    37 
    38 //########################################################################################################################
    39 //-- parameters that can be defined in estart.txt file under [Drive%] section
    40 
    41 //=======================================================================================================================
    42 //-- FAT volumes mounting related settings
    43 //=======================================================================================================================
    44 
    45 //-- if this parameter is not 0, ScanDrive will skip finalised volume. Applicable for FAT16/32
    46 //-- e.g:   FAT_ScanDrv_SkipFinalisedVolume 1
    47 _LIT8(KPN_ScanDrvSkipFinalisedVolume,"FAT_ScanDrv_SkipFinalisedVolume");  //-- parameter key name
    48 static const TUint32 KDef_ScanDrvSkipFinalisedVolume = 0; //-- parameter default value
    49 
    50 //-- if this parameter is not 0, enables asynchronous mounting FAT32 volumes. 
    51 //-- At present it means enabling/disabling FAT32 background scanning for free clusters. Applicable for FAT32 only
    52 //-- e.g:   FAT_FAT32_AsynchMount=0
    53 _LIT8(KPN_FAT32_AsynchMount, "FAT_FAT32_AsynchMount"); 
    54 static const TUint32 KDef_FAT32_AsynchMount = 1;
    55 
    56 //-- Using FSInfo sector data during FAT32 mount to find out number of free clusters etc.
    57 //-- e.g:   FAT_FAT32_UseFsInfo=1
    58 _LIT8(KPN_FAT32_UseFsInfoOnMount, "FAT_FAT32_UseFsInfo"); 
    59 static const TUint32 KDef_FAT32_UseFsInfoOnMount = 1;
    60 
    61 //-- Using FAT bit supercache for fast free cluster lookup
    62 //-- e.g:   FAT_FAT32_UseBitSupercache 0
    63 _LIT8(KPN_FAT32_UseFatBitSupercache, "FAT_FAT32_UseBitSupercache"); 
    64 static const TUint32 KDef_FAT32_UseFatBitSupercache = 1;
    65 
    66 
    67 //-- if this parameter is not 0, "clean shutdown mask" bit in FAT16[1] will be used during volume finalisation.
    68 //-- Otherwise, FAT16[1] will not be affected during finalisation
    69 //-- e.g:   KDef_FAT16_UseCleanShutDownBit 0
    70 _LIT8(KPN_FAT16_UseCleanShutDownBit,"FAT16_UseCleanShutDownBit");  //-- parameter key name
    71 static const TUint32 KDef_FAT16_UseCleanShutDownBit = 1;           //-- parameter default value
    72 
    73 
    74 //=======================================================================================================================
    75 //-- FAT directory cache settings
    76 //=======================================================================================================================
    77 //-- FAT_DirCache <CacheSizeKB>,<Log2(max page size)>
    78 //-- e.g:   FAT_DirCache 16,12
    79 _LIT8(KPN_FAT_DirCache, "FAT_DirCache"); 
    80 
    81 static const TUint32 KDef_KDirCacheSizeKB = 16;      //-- default value for the total directory cache size, kilobytes. 16K by default
    82 static const TUint32 KDef_MaxDirCachePageSzLog2 = 12;//-- default value for directory cache single page maximal size Log2, 2^12 (4K) by default
    83 
    84 
    85 //=======================================================================================================================
    86 //-- FAT cache settings
    87 //=======================================================================================================================
    88 
    89 //-- Fat16 fixed cache
    90 //-- FAT_FAT16FixedCache <Log2(read granularity)>,<Log2(Write granularity)> 
    91 //-- e.g:   FAT_FAT16FixedCache 12,9 
    92 _LIT8(KPN_FAT_FAT16FixedCache, "FAT_FAT16FixedCache"); 
    93 static const TUint32 KDef_FAT16_FixedCache_Read_Granularity_LOG2 = 12;  //-- read granularity  Log2, 4K
    94 static const TUint32 KDef_FAT16_FixedCache_Write_Granularity_LOG2 = 9;  //-- write granularity Log2, 512 bytes    
    95 
    96 
    97 //-- Fat32 LRU cache
    98 //-- FAT_FAT32LruCache <Size KB>,<Log2(read granularity)>,<Log2(Write granularity)> 
    99 //-- e.g:   FAT_FAT32LruCache 128,12,9
   100 _LIT8(KPN_FAT_FAT32LruCache, "FAT_FAT32LruCache"); 
   101 
   102 
   103 static const TUint32 KDef_FAT32_LruCache_SizeKB = 128;                  //-- LRU cache size, 128KB
   104 static const TUint32 KDef_FAT32_LruCache_Read_Granularity_LOG2 = 12;    //-- read granularity  Log2, 4K     
   105 static const TUint32 KDef_FAT32_LruCache_Write_Granularity_LOG2 = 9;    //-- write granularity Log2, 512 bytes      
   106 
   107 
   108 //=======================================================================================================================
   109 //-- FAT leaf directory cache settings
   110 //=======================================================================================================================
   111 //-- A leaf directory cache for Fat volumes
   112 _LIT8(KPN_FAT_LeafDirCache, "FAT_LeafDirCacheSize"); 
   113 static const TUint32 KDef_KLeafDirCacheSize = 1;    //-- default number of the most recently visited leaf dirs to be cached
   114 
   115 //=======================================================================================================================
   116 //-- New directory cache settings
   117 //=======================================================================================================================
   118 //-- New directory cache uses the global cache memory manager for dynamic size allocation
   119 _LIT8(KPN_FAT_DynamicDirCacheMin, "FAT_DirCacheSizeMin"); 
   120 _LIT8(KPN_FAT_DynamicDirCacheMax, "FAT_DirCacheSizeMax"); 
   121 static const TUint32 KDef_DynamicDirCacheMin = 128;     // default minimum fat dir cache size in KB
   122 static const TUint32 KDef_DynamicDirCacheMax = 128;     // default maximum fat dir cache size in KB
   123 //-- default value for directory cache single page maximal size Log2, 2^14 (16K) by default
   124 static const TUint32 KDef_MaxDynamicDirCachePageSzLog2 = 14;
   125 
   126 
   127 
   128 
   129 
   130 
   131 
   132 
   133 //########################################################################################################################
   134 
   135 
   136 
   137 //-----------------------------------------------------------------------------
   138 /**
   139     Extract a token from the comma-separated tokens string.
   140 
   141     @param  aSrc        source string descriptor
   142     @param  aTokenNo    token number to extract (the 1st token is number 0)
   143     @param  aToken      on success there will be extracted token
   144     
   145     @return ETrue on success and an extracted token in aToken
   146 */
   147 static TBool GetCSV_Token(const TDesC8& aSrc, TUint aTokenNo, TPtrC8& aToken)
   148     {
   149 
   150     const TChar chDelim = ','; //-- token delimiter, comma
   151     TInt nRes;
   152     
   153     //-- 1. find the beginning of the token we are looking for
   154     TPtrC8 ptrCurrToken(aSrc);
   155     for(TUint i=0; i<aTokenNo; ++i)
   156         {
   157         const TInt len = ptrCurrToken.Length();
   158 
   159         nRes = ptrCurrToken.Locate(chDelim);
   160         if(nRes == KErrNotFound)
   161             return EFalse; //-- did tot find the required token
   162 
   163         ptrCurrToken.Set(ptrCurrToken.Right(len-nRes-1));
   164         }
   165 
   166     //-- 2. set the end position of the token we found
   167     aToken.Set(ptrCurrToken);
   168 
   169     nRes = ptrCurrToken.Locate(chDelim);
   170     if(nRes != KErrNotFound)
   171         {
   172         aToken.Set(ptrCurrToken.Left(nRes));
   173         }
   174 
   175     return ETrue;
   176     }
   177 
   178 
   179 //-----------------------------------------------------------------------------
   180 /**
   181     Extract a token from the comma-separated tokens string and try to convert it into TInt
   182 
   183     @param  aSrc        source string descriptor
   184     @param  aTokenNo    token number to extract (the 1st token is number 0)
   185     @param  aVal        On success will contain the value represented by the token
   186 
   187     @return ETrue if the token is extracted and converted to TInt OK, in this case aVal contains value
   188 */
   189 static TBool GetIntTokenVal(const TDesC8& aSrc, TUint aTokenNo, TInt& aVal)
   190 {
   191     TPtrC8      ptrToken;
   192     TLex8       lex;
   193     TInt        val;
   194 
   195     if(!GetCSV_Token(aSrc, aTokenNo, ptrToken))
   196         return EFalse;
   197 
   198     lex.Assign(ptrToken);
   199     lex.SkipSpace();
   200     
   201     if(lex.Val(val) != KErrNone)
   202         return EFalse;
   203 
   204     aVal = val;
   205     return ETrue;
   206 }
   207 
   208 static TBool GetIntTokenVal(const TDesC8& aSrc, TUint aTokenNo, TUint16& aVal)
   209 {
   210     TInt  val;
   211     if(!GetIntTokenVal(aSrc, aTokenNo, val))
   212         return EFalse;
   213 
   214     aVal = (TUint16)val;
   215     return ETrue;
   216 }
   217 
   218 
   219 //-----------------------------------------------------------------------------
   220 TFatConfig::TFatConfig()
   221     {
   222     iInitialised = EFalse;
   223     }
   224 
   225 //-----------------------------------------------------------------------------
   226 
   227 /**
   228     reads FAT parameters from estart.txt file.
   229     @param  aDrvNumber a valid drive number
   230     @param  aForceRead if ETrue parameters will be forcedly re-read.
   231 */
   232 void TFatConfig::ReadConfig(TInt aDrvNumber, TBool aForceRead /*=EFalse*/)
   233     {
   234     if(aForceRead)
   235         iInitialised = EFalse;
   236 
   237     if(iInitialised)
   238         return;
   239 
   240     //__PRINT1(_L("#>- TFatConfig::ReadConfig() drive:%d\n"),aDrvNumber);
   241     ASSERT(aDrvNumber >= EDriveA && aDrvNumber <= EDriveZ);
   242     
   243     //-- make a section name, like "DriveX"
   244     TBuf8<32> section;
   245     section.Format(_L8("Drive%c"), 'A'+aDrvNumber);
   246     
   247     //-- read values from estart.txt and cache them
   248     iScanDrvSkipFinalisedVolume = ReadUint(section, KPN_ScanDrvSkipFinalisedVolume, KDef_ScanDrvSkipFinalisedVolume);
   249     iFAT32_AsynchMount          = ReadUint(section, KPN_FAT32_AsynchMount,          KDef_FAT32_AsynchMount);
   250     iFAT32_UseFSInfoOnMount     = ReadUint(section, KPN_FAT32_UseFsInfoOnMount,     KDef_FAT32_UseFsInfoOnMount);
   251     iFAT32_UseBitSupercache     = ReadUint(section, KPN_FAT32_UseFatBitSupercache,  KDef_FAT32_UseFatBitSupercache);
   252     iFAT16_UseCleanShutDownBit  = ReadUint(section, KPN_FAT16_UseCleanShutDownBit, KDef_FAT16_UseCleanShutDownBit);
   253 
   254     // If leaf dir cache is supported, read the configuration from estart.txt file
   255     iLeafDirCacheSize           = ReadUint(section, KPN_FAT_LeafDirCache,           KDef_KLeafDirCacheSize);
   256     ProcessDynamicDirCacheParams(section);  //-- read dynamic dir cache parameters;
   257 
   258     ProcessDirCacheParams(section); //-- read FAT directory cache parameters
   259     ProcessFatCacheParams(section); //-- read FAT cache parameters
   260 
   261     iInitialised = ETrue;
   262 
   263     DumpParameters(); //-- print out parameters in debug mode
   264     }
   265 
   266 
   267 //-----------------------------------------------------------------------------
   268 /** 
   269     process dynamic directory cache parameters 
   270     @param aSection section name, like "DriveX"
   271 */
   272 void TFatConfig::ProcessDynamicDirCacheParams(const TDesC8& aSection)
   273     {
   274     // we have to process the data in this file as the default values are all static variables, which means
   275     //  their scope is limited within this file only.
   276     iDynamicDirCacheMaxPageSizeLog2 = KDef_MaxDynamicDirCachePageSzLog2; 
   277     iDynamicDirCacheSizeMinKB = ReadUint(aSection, KPN_FAT_DynamicDirCacheMin, KDef_DynamicDirCacheMin);
   278     iDynamicDirCacheSizeMaxKB = ReadUint(aSection, KPN_FAT_DynamicDirCacheMax, KDef_DynamicDirCacheMax);
   279 
   280     // if less than default values, set to default values
   281     if (iDynamicDirCacheSizeMinKB < KDef_DynamicDirCacheMin)
   282         iDynamicDirCacheSizeMinKB = KDef_DynamicDirCacheMin;
   283     if (iDynamicDirCacheSizeMaxKB < KDef_DynamicDirCacheMax)
   284         iDynamicDirCacheSizeMaxKB = KDef_DynamicDirCacheMax;
   285 
   286     // validate settings for those values that the default values does not apply onto them
   287     __ASSERT_ALWAYS(iDynamicDirCacheSizeMinKB <= iDynamicDirCacheSizeMaxKB, Fault(EFatBadParameter));
   288     }
   289 
   290 /** 
   291     process directory cache parameters 
   292     @param aSection section name, like "DriveX"
   293 */
   294 void TFatConfig::ProcessDirCacheParams(const TDesC8& aSection)
   295     {
   296     TBuf8<128>  buf;
   297 
   298     //-- set default values.
   299     iDirCacheSizeKB = KDef_KDirCacheSizeKB;
   300     iDirCacheMaxPageSizeLog2 = KDef_MaxDirCachePageSzLog2;
   301 
   302     //-- read a string containing DirCache parameters
   303     //-- it looks like this: FAT_DirCache cacheSzKB, maxPageSzBytes
   304     if(!F32Properties::GetString(aSection, KPN_FAT_DirCache, buf))
   305         return;
   306     
   307     GetIntTokenVal(buf, 0, iDirCacheSizeKB);          //-- 1. extract directory cache size in KB. this is token 0
   308     GetIntTokenVal(buf, 1, iDirCacheMaxPageSizeLog2); //-- 2. extract directory cache max page size in bytes Log2. this is token 1  
   309     }
   310 
   311 //-----------------------------------------------------------------------------
   312 /** 
   313     process fat cache parameters 
   314     @param aSection section name, like "DriveX"
   315 */
   316 void TFatConfig::ProcessFatCacheParams(const TDesC8& aSection)
   317 {
   318     TBuf8<128>  buf;
   319     //-- set default values.
   320     iFat16FixedCacheReadGrLog2 = KDef_FAT16_FixedCache_Read_Granularity_LOG2;
   321     iFat16FixedCacheWriteGrLog2 = KDef_FAT16_FixedCache_Write_Granularity_LOG2;
   322 
   323     iFat32LRUCacheSizeKB = KDef_FAT32_LruCache_SizeKB;
   324     iFat32LRUCacheReadGrLog2 = KDef_FAT32_LruCache_Read_Granularity_LOG2;
   325     iFat32LRUCacheWriteGrLog2 = KDef_FAT32_LruCache_Write_Granularity_LOG2;
   326 
   327     //-- read a string containing FAT16 fixed cache parameters
   328     if(F32Properties::GetString(aSection, KPN_FAT_FAT16FixedCache, buf))
   329     {
   330         GetIntTokenVal(buf, 0, iFat16FixedCacheReadGrLog2);  //-- 1. extract Log2(FAT16 fixed cache read granularity)
   331         GetIntTokenVal(buf, 1, iFat16FixedCacheWriteGrLog2); //-- 2. extract Log2(FAT16 fixed cache write granularity)
   332     }
   333 
   334     //-- read a string containing FAT32 LRU cache parameters
   335     if(F32Properties::GetString(aSection, KPN_FAT_FAT32LruCache, buf))
   336     {
   337         GetIntTokenVal(buf, 0, iFat32LRUCacheSizeKB);        //-- 1. extract FAT32 LRU cache size, Kbytes
   338         GetIntTokenVal(buf, 1, iFat32LRUCacheReadGrLog2);    //-- 2. extract Log2(FAT32 LRU cache read granularity)
   339         GetIntTokenVal(buf, 2, iFat32LRUCacheWriteGrLog2);   //-- 3. extract Log2(FAT32 LRU cache write granularity)
   340     }
   341 }
   342 
   343 
   344 //-----------------------------------------------------------------------------
   345 /**
   346     Just a helper method. Reads TUint32 value from the estart.txt
   347     
   348     @param  aSection        section name, e.g. [DriveD]
   349     @param  aKeyName        Key name
   350     @param  aDefaultValue   Default value to return in parameter isn't found
   351     @return a value from config file or default aDefaultValue
   352 */
   353 TUint32 TFatConfig::ReadUint(const TDesC8& aSection, const TDesC8& aKeyName, TUint32 aDefaultValue) const
   354     {
   355     TInt32 val = aDefaultValue;
   356     // coverity[check_return] coverity[unchecked_value]
   357     F32Properties::GetInt(aSection, aKeyName, val);
   358 
   359     return val;
   360     }
   361 
   362 //-----------------------------------------------------------------------------
   363 /** Debug method, prints out the parameters*/
   364 void TFatConfig::DumpParameters() const
   365     {
   366 #ifdef _DEBUG
   367 
   368     ASSERT(iInitialised);
   369     __PRINT(_L("#>- TFatConfig parameters:\n"));
   370 
   371     DoDumpUintParam(KPN_ScanDrvSkipFinalisedVolume, iScanDrvSkipFinalisedVolume);
   372     DoDumpUintParam(KPN_FAT32_AsynchMount, iFAT32_AsynchMount);
   373     DoDumpUintParam(KPN_FAT32_UseFsInfoOnMount, iFAT32_UseFSInfoOnMount);
   374     DoDumpUintParam(KPN_FAT32_UseFatBitSupercache, iFAT32_UseBitSupercache);
   375     DoDumpUintParam(KPN_FAT16_UseCleanShutDownBit, iFAT16_UseCleanShutDownBit);
   376 
   377     DoDumpUintParam(_L8("FAT_DirCache Size, KB"), iDirCacheSizeKB);
   378     DoDumpUintParam(_L8("FAT_DirCache MaxPage Size Log2"), iDirCacheMaxPageSizeLog2);
   379 
   380     DoDumpUintParam(_L8("FAT_16Cache RdGr Log2"), iFat16FixedCacheReadGrLog2);
   381     DoDumpUintParam(_L8("FAT_16Cache WrGr Log2"), iFat16FixedCacheWriteGrLog2);
   382 
   383     DoDumpUintParam(_L8("FAT_32Cache Size, KB"),  iFat32LRUCacheSizeKB);
   384     DoDumpUintParam(_L8("FAT_32Cache RdGr Log2"), iFat32LRUCacheReadGrLog2);
   385     DoDumpUintParam(_L8("FAT_32Cache WrGr Log2"), iFat32LRUCacheWriteGrLog2);
   386 
   387     __PRINT(_L("#>------ end -------<#\n\n"));
   388 
   389 #endif
   390     }
   391 
   392 void TFatConfig::DoDumpUintParam(const TDesC8& aKeyName, TUint32 aParam) const
   393     {
   394 #ifdef _DEBUG
   395     TBuf<100> buf;
   396 
   397     buf.Copy(aKeyName);
   398     buf.Insert(0,_L("#>-  "));
   399     buf.AppendFormat(_L(": %d"), aParam);
   400     __PRINT(buf);
   401 #else
   402     (void)aKeyName; (void)aParam; //-- get rid of warning
   403 
   404 #endif
   405     }
   406 
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