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<hr><h1>gdalrasterblock.cpp</h1><div class="fragment"><pre>00001 <font class="comment">/******************************************************************************</font>
00002 <font class="comment"> * Copyright (c) 1998, Frank Warmerdam</font>
00003 <font class="comment"> *</font>
00004 <font class="comment"> * Permission is hereby granted, free of charge, to any person obtaining a</font>
00005 <font class="comment"> * copy of this software and associated documentation files (the "Software"),</font>
00006 <font class="comment"> * to deal in the Software without restriction, including without limitation</font>
00007 <font class="comment"> * the rights to use, copy, modify, merge, publish, distribute, sublicense,</font>
00008 <font class="comment"> * and/or sell copies of the Software, and to permit persons to whom the</font>
00009 <font class="comment"> * Software is furnished to do so, subject to the following conditions:</font>
00010 <font class="comment"> *</font>
00011 <font class="comment"> * The above copyright notice and this permission notice shall be included</font>
00012 <font class="comment"> * in all copies or substantial portions of the Software.</font>
00013 <font class="comment"> *</font>
00014 <font class="comment"> * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS</font>
00015 <font class="comment"> * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,</font>
00016 <font class="comment"> * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL</font>
00017 <font class="comment"> * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER</font>
00018 <font class="comment"> * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING</font>
00019 <font class="comment"> * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER</font>
00020 <font class="comment"> * DEALINGS IN THE SOFTWARE.</font>
00021 <font class="comment"> ******************************************************************************</font>
00022 <font class="comment"> *</font>
00023 <font class="comment"> * gdalrasterblock.cpp</font>
00024 <font class="comment"> *</font>
00025 <font class="comment"> * The GDALRasterBlock class.</font>
00026 <font class="comment"> *</font>
00027 <font class="comment"> * </font>
00028 <font class="comment"> * $Log: gdalrasterblock_cpp-source.html,v $
00028 <font class="comment"> * Revision 1.13 2002/12/21 19:13:13 warmerda
00028 <font class="comment"> * updated
00028 <font class="comment"> *</font>
00029 <font class="comment"> * Revision 1.8 2002/07/09 20:33:12 warmerda</font>
00030 <font class="comment"> * expand tabs</font>
00031 <font class="comment"> *</font>
00032 <font class="comment"> * Revision 1.7 2001/09/27 16:33:41 warmerda</font>
00033 <font class="comment"> * fixed problems with blocks larger than 2GB/8</font>
00034 <font class="comment"> *</font>
00035 <font class="comment"> * Revision 1.6 2001/07/18 04:04:30 warmerda</font>
00036 <font class="comment"> * added CPL_CVSID</font>
00037 <font class="comment"> *</font>
00038 <font class="comment"> * Revision 1.5 2001/06/22 21:00:06 warmerda</font>
00039 <font class="comment"> * fixed support for caching override by environment variable</font>
00040 <font class="comment"> *</font>
00041 <font class="comment"> * Revision 1.4 2001/06/22 20:09:13 warmerda</font>
00042 <font class="comment"> * added GDAL_CACHEMAX environment variable support</font>
00043 <font class="comment"> *</font>
00044 <font class="comment"> * Revision 1.3 2000/03/31 13:42:49 warmerda</font>
00045 <font class="comment"> * added debugging code</font>
00046 <font class="comment"> *</font>
00047 <font class="comment"> * Revision 1.2 2000/03/24 00:09:05 warmerda</font>
00048 <font class="comment"> * rewrote cache management</font>
00049 <font class="comment"> *</font>
00050 <font class="comment"> * Revision 1.1 1998/12/31 18:52:58 warmerda</font>
00051 <font class="comment"> * New</font>
00052 <font class="comment"> *</font>
00053 <font class="comment"> */</font>
00054
00055 <font class="preprocessor">#include "gdal_priv.h"</font>
00056
00057 CPL_CVSID(<font class="stringliteral">"$Id: gdalrasterblock_cpp-source.html,v 1.13 2002/12/21 19:13:13 warmerda Exp $"</font>);
00058
00059 <font class="keyword">static</font> <font class="keywordtype">int</font> nTileAgeTicker = 0;
00060 <font class="keyword">static</font> <font class="keywordtype">int</font> bCacheMaxInitialized = FALSE;
00061 <font class="keyword">static</font> <font class="keywordtype">int</font> nCacheMax = 5 * 1024*1024;
00062 <font class="keyword">static</font> <font class="keywordtype">int</font> nCacheUsed = 0;
00063
00064 <font class="keyword">static</font> <a class="code" href="class_GDALRasterBlock.html">GDALRasterBlock</a> *poOldest = NULL; <font class="comment">/* tail */</font>
00065 <font class="keyword">static</font> <a class="code" href="class_GDALRasterBlock.html">GDALRasterBlock</a> *poNewest = NULL; <font class="comment">/* head */</font>
00066
00067
00068 <font class="comment">/************************************************************************/</font>
00069 <font class="comment">/* GDALSetCacheMax() */</font>
00070 <font class="comment">/************************************************************************/</font>
00071
00072 <font class="keywordtype">void</font> GDALSetCacheMax( <font class="keywordtype">int</font> nNewSize )<font class="keyword"></font>
00073 <font class="keyword"></font>
00074 <font class="keyword"></font>{
00075 nCacheMax = nNewSize;
00076 <font class="keywordflow">if</font>( nCacheUsed > nCacheMax )
00077 GDALFlushCacheBlock();
00078 }
00079
00080 <font class="comment">/************************************************************************/</font>
00081 <font class="comment">/* GDALGetCacheMax() */</font>
00082 <font class="comment">/************************************************************************/</font>
00083
00084 <font class="keywordtype">int</font> GDALGetCacheMax()<font class="keyword"></font>
00085 <font class="keyword"></font>{
00086 <font class="keywordflow">if</font>( !bCacheMaxInitialized )
00087 {
00088 <font class="keywordflow">if</font>( getenv(<font class="stringliteral">"GDAL_CACHEMAX"</font>) != NULL )
00089 {
00090 nCacheMax = atoi(getenv(<font class="stringliteral">"GDAL_CACHEMAX"</font>));
00091 <font class="keywordflow">if</font>( nCacheMax < 1000 )
00092 nCacheMax *= 1024 * 1024;
00093 }
00094 bCacheMaxInitialized = TRUE;
00095 }
00096
00097 <font class="keywordflow">return</font> nCacheMax;
00098 }
00099
00100 <font class="comment">/************************************************************************/</font>
00101 <font class="comment">/* GDALGetCacheUsed() */</font>
00102 <font class="comment">/************************************************************************/</font>
00103
00104 <font class="keywordtype">int</font> GDALGetCacheUsed()<font class="keyword"></font>
00105 <font class="keyword"></font>{
00106 <font class="keywordflow">return</font> nCacheUsed;
00107 }
00108
00109 <font class="comment">/************************************************************************/</font>
00110 <font class="comment">/* GDALFlushCacheBlock() */</font>
00111 <font class="comment">/* */</font>
00112 <font class="comment">/* The workhorse of cache management! */</font>
00113 <font class="comment">/************************************************************************/</font>
00114
00115 <font class="keywordtype">int</font> GDALFlushCacheBlock()<font class="keyword"></font>
00116 <font class="keyword"></font>
00117 <font class="keyword"></font>{
00118 <font class="keywordflow">if</font>( poOldest == NULL )
00119 <font class="keywordflow">return</font> FALSE;
00120 poOldest->GetBand()->FlushBlock( poOldest->GetXOff(),
00121 poOldest->GetYOff() );
00122
00123 <font class="keywordflow">return</font> TRUE;
00124 }
00125
00126 <font class="comment">/************************************************************************/</font>
00127 <font class="comment">/* GDALRasterBand() */</font>
00128 <font class="comment">/************************************************************************/</font>
00129
00130 GDALRasterBlock::GDALRasterBlock( <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> *poBandIn,
00131 <font class="keywordtype">int</font> nXOffIn, <font class="keywordtype">int</font> nYOffIn )<font class="keyword"></font>
00132 <font class="keyword"></font>
00133 <font class="keyword"></font>{
00134 poBand = poBandIn;
00135
00136 poBand-><a class="code" href="class_GDALRasterBand.html#a7">GetBlockSize</a>( &nXSize, &nYSize );
00137 eType = poBand-><a class="code" href="class_GDALRasterBand.html#a6">GetRasterDataType</a>();
00138 pData = NULL;
00139 bDirty = FALSE;
00140
00141 poNext = poPrevious = NULL;
00142
00143 nXOff = nXOffIn;
00144 nYOff = nYOffIn;
00145 }
00146
00147 <font class="comment">/************************************************************************/</font>
00148 <font class="comment">/* ~GDALRasterBlock() */</font>
00149 <font class="comment">/************************************************************************/</font>
00150
00151 GDALRasterBlock::~GDALRasterBlock()<font class="keyword"></font>
00152 <font class="keyword"></font>
00153 <font class="keyword"></font>{
00154 <font class="keywordflow">if</font>( pData != NULL )
00155 {
00156 <font class="keywordtype">int</font> nSizeInBytes;
00157
00158 VSIFree( pData );
00159
00160 nSizeInBytes = (nXSize * nYSize * GDALGetDataTypeSize(eType)+7)/8;
00161 nCacheUsed -= nSizeInBytes;
00162 }
00163
00164 <font class="keywordflow">if</font>( poOldest == <font class="keyword">this</font> )
00165 poOldest = poPrevious;
00166
00167 <font class="keywordflow">if</font>( poNewest == <font class="keyword">this</font> )
00168 {
00169 poNewest = poNext;
00170 }
00171
00172 <font class="keywordflow">if</font>( poPrevious != NULL )
00173 poPrevious->poNext = poNext;
00174
00175 <font class="keywordflow">if</font>( poNext != NULL )
00176 poNext->poPrevious = poPrevious;
00177
00178 <font class="preprocessor">#ifdef ENABLE_DEBUG</font>
00179 <font class="preprocessor"></font> Verify();
00180 <font class="preprocessor">#endif</font>
00181 <font class="preprocessor"></font>
00182 nAge = -1;
00183 }
00184
00185 <font class="comment">/************************************************************************/</font>
00186 <font class="comment">/* Verify() */</font>
00187 <font class="comment">/************************************************************************/</font>
00188
00189 <font class="keywordtype">void</font> GDALRasterBlock::Verify()<font class="keyword"></font>
00190 <font class="keyword"></font>
00191 <font class="keyword"></font>{
00192 CPLAssert( (poNewest == NULL && poOldest == NULL)
00193 || (poNewest != NULL && poOldest != NULL) );
00194
00195 <font class="keywordflow">if</font>( poNewest != NULL )
00196 {
00197 CPLAssert( poNewest->poPrevious == NULL );
00198 CPLAssert( poOldest->poNext == NULL );
00199
00200
00201 <font class="keywordflow">for</font>( <a class="code" href="class_GDALRasterBlock.html">GDALRasterBlock</a> *poBlock = poNewest;
00202 poBlock != NULL;
00203 poBlock = poBlock->poNext )
00204 {
00205 <font class="keywordflow">if</font>( poBlock->poPrevious )
00206 {
00207 CPLAssert( poBlock->poPrevious->poNext == poBlock );
00208 }
00209
00210 <font class="keywordflow">if</font>( poBlock->poNext )
00211 {
00212 CPLAssert( poBlock->poNext->poPrevious == poBlock );
00213 }
00214 }
00215 }
00216 }
00217
00218 <font class="comment">/************************************************************************/</font>
00219 <font class="comment">/* Write() */</font>
00220 <font class="comment">/************************************************************************/</font>
00221
00222 CPLErr GDALRasterBlock::Write()<font class="keyword"></font>
00223 <font class="keyword"></font>
00224 <font class="keyword"></font>{
00225 <font class="keywordflow">if</font>( !GetDirty() )
00226 <font class="keywordflow">return</font> CE_None;
00227
00228 <font class="keywordflow">if</font>( poBand == NULL )
00229 <font class="keywordflow">return</font> CE_Failure;
00230
00231 MarkClean();
00232
00233 <font class="keywordflow">return</font> poBand-><a class="code" href="class_GDALRasterBand.html#b1">IWriteBlock</a>( nXOff, nYOff, pData );
00234 }
00235
00236 <font class="comment">/************************************************************************/</font>
00237 <font class="comment">/* Touch() */</font>
00238 <font class="comment">/************************************************************************/</font>
00239
00240 <font class="keywordtype">void</font> GDALRasterBlock::Touch()<font class="keyword"></font>
00241 <font class="keyword"></font>
00242 <font class="keyword"></font>{
00243 nAge = nTileAgeTicker++;
00244
00245 <font class="keywordflow">if</font>( poNewest == <font class="keyword">this</font> )
00246 <font class="keywordflow">return</font>;
00247
00248 <font class="keywordflow">if</font>( poOldest == <font class="keyword">this</font> )
00249 poOldest = this->poPrevious;
00250
00251 <font class="keywordflow">if</font>( poPrevious != NULL )
00252 poPrevious->poNext = poNext;
00253
00254 <font class="keywordflow">if</font>( poNext != NULL )
00255 poNext->poPrevious = poPrevious;
00256
00257 poPrevious = NULL;
00258 poNext = poNewest;
00259
00260 <font class="keywordflow">if</font>( poNewest != NULL )
00261 {
00262 CPLAssert( poNewest->poPrevious == NULL );
00263 poNewest->poPrevious = <font class="keyword">this</font>;
00264 }
00265 poNewest = <font class="keyword">this</font>;
00266
00267 <font class="keywordflow">if</font>( poOldest == NULL )
00268 {
00269 CPLAssert( poPrevious == NULL && poNext == NULL );
00270 poOldest = <font class="keyword">this</font>;
00271 }
00272 <font class="preprocessor">#ifdef ENABLE_DEBUG</font>
00273 <font class="preprocessor"></font> Verify();
00274 <font class="preprocessor">#endif</font>
00275 <font class="preprocessor"></font>}
00276
00277 <font class="comment">/************************************************************************/</font>
00278 <font class="comment">/* Internalize() */</font>
00279 <font class="comment">/************************************************************************/</font>
00280
00281 CPLErr GDALRasterBlock::Internalize()<font class="keyword"></font>
00282 <font class="keyword"></font>
00283 <font class="keyword"></font>{
00284 <font class="keywordtype">void</font> *pNewData;
00285 <font class="keywordtype">int</font> nSizeInBytes;
00286 <font class="keywordtype">int</font> nCurCacheMax = GDALGetCacheMax();
00287
00288 nSizeInBytes = nXSize * nYSize * (GDALGetDataTypeSize(eType) / 8);
00289
00290 pNewData = VSIMalloc( nSizeInBytes );
00291 <font class="keywordflow">if</font>( pNewData == NULL )
00292 <font class="keywordflow">return</font>( CE_Failure );
00293
00294 <font class="keywordflow">if</font>( pData != NULL )
00295 memcpy( pNewData, pData, nSizeInBytes );
00296
00297 pData = pNewData;
00298
00299 <font class="comment">/* -------------------------------------------------------------------- */</font>
00300 <font class="comment">/* Flush old blocks if we are nearing our memory limit. */</font>
00301 <font class="comment">/* -------------------------------------------------------------------- */</font>
00302 nCacheUsed += nSizeInBytes;
00303 <font class="keywordflow">while</font>( nCacheUsed > nCurCacheMax )
00304 {
00305 <font class="keywordtype">int</font> nOldCacheUsed = nCacheUsed;
00306
00307 GDALFlushCacheBlock();
00308
00309 <font class="keywordflow">if</font>( nCacheUsed == nOldCacheUsed )
00310 {
00311 <font class="keyword">static</font> <font class="keywordtype">int</font> bReported = FALSE;
00312
00313 <font class="keywordflow">if</font>( !bReported )
00314 {
00315 bReported = TRUE;
00316 }
00317 <font class="keywordflow">break</font>;
00318 }
00319 }
00320
00321 <font class="comment">/* -------------------------------------------------------------------- */</font>
00322 <font class="comment">/* Add this block to the list. */</font>
00323 <font class="comment">/* -------------------------------------------------------------------- */</font>
00324 Touch();
00325 <font class="keywordflow">return</font>( CE_None );
00326 }
00327
00328 <font class="comment">/************************************************************************/</font>
00329 <font class="comment">/* MarkDirty() */</font>
00330 <font class="comment">/************************************************************************/</font>
00331
00332 <font class="keywordtype">void</font> GDALRasterBlock::MarkDirty()<font class="keyword"></font>
00333 <font class="keyword"></font>
00334 <font class="keyword"></font>{
00335 bDirty = TRUE;
00336 }
00337
00338
00339 <font class="comment">/************************************************************************/</font>
00340 <font class="comment">/* MarkClean() */</font>
00341 <font class="comment">/************************************************************************/</font>
00342
00343 <font class="keywordtype">void</font> GDALRasterBlock::MarkClean()<font class="keyword"></font>
00344 <font class="keyword"></font>
00345 <font class="keyword"></font>{
00346 bDirty = FALSE;
00347 }
00348
00349
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