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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 1.10 2002/04/16 13:11:49 warmerda
00028 <font class="comment"> * updated
00028 <font class="comment"> *</font>
00029 <font class="comment"> * Revision 1.7 2001/09/27 16:33:41 warmerda</font>
00030 <font class="comment"> * fixed problems with blocks larger than 2GB/8</font>
00031 <font class="comment"> *</font>
00032 <font class="comment"> * Revision 1.6 2001/07/18 04:04:30 warmerda</font>
00033 <font class="comment"> * added CPL_CVSID</font>
00034 <font class="comment"> *</font>
00035 <font class="comment"> * Revision 1.5 2001/06/22 21:00:06 warmerda</font>
00036 <font class="comment"> * fixed support for caching override by environment variable</font>
00037 <font class="comment"> *</font>
00038 <font class="comment"> * Revision 1.4 2001/06/22 20:09:13 warmerda</font>
00039 <font class="comment"> * added GDAL_CACHEMAX environment variable support</font>
00040 <font class="comment"> *</font>
00041 <font class="comment"> * Revision 1.3 2000/03/31 13:42:49 warmerda</font>
00042 <font class="comment"> * added debugging code</font>
00043 <font class="comment"> *</font>
00044 <font class="comment"> * Revision 1.2 2000/03/24 00:09:05 warmerda</font>
00045 <font class="comment"> * rewrote cache management</font>
00046 <font class="comment"> *</font>
00047 <font class="comment"> * Revision 1.1 1998/12/31 18:52:58 warmerda</font>
00048 <font class="comment"> * New</font>
00049 <font class="comment"> *</font>
00050 <font class="comment"> */</font>
00051
00052 <font class="preprocessor">#include "gdal_priv.h"</font>
00053
00054 CPL_CVSID(<font class="stringliteral">"$Id: gdalrasterblock_cpp-source.html,v 1.10 2002/04/16 13:11:49 warmerda Exp $"</font>);
00055
00056 <font class="keyword">static</font> <font class="keywordtype">int</font> nTileAgeTicker = 0;
00057 <font class="keyword">static</font> <font class="keywordtype">int</font> bCacheMaxInitialized = FALSE;
00058 <font class="keyword">static</font> <font class="keywordtype">int</font> nCacheMax = 5 * 1024*1024;
00059 <font class="keyword">static</font> <font class="keywordtype">int</font> nCacheUsed = 0;
00060
00061 <font class="keyword">static</font> <a class="code" href="class_GDALRasterBlock.html">GDALRasterBlock</a> *poOldest = NULL; <font class="comment">/* tail */</font>
00062 <font class="keyword">static</font> <a class="code" href="class_GDALRasterBlock.html">GDALRasterBlock</a> *poNewest = NULL; <font class="comment">/* head */</font>
00063
00064
00065 <font class="comment">/************************************************************************/</font>
00066 <font class="comment">/* GDALSetCacheMax() */</font>
00067 <font class="comment">/************************************************************************/</font>
00068
00069 <font class="keywordtype">void</font> GDALSetCacheMax( <font class="keywordtype">int</font> nNewSize )<font class="keyword"></font>
00070 <font class="keyword"></font>
00071 <font class="keyword"></font>{
00072 nCacheMax = nNewSize;
00073 <font class="keywordflow">if</font>( nCacheUsed > nCacheMax )
00074 GDALFlushCacheBlock();
00075 }
00076
00077 <font class="comment">/************************************************************************/</font>
00078 <font class="comment">/* GDALGetCacheMax() */</font>
00079 <font class="comment">/************************************************************************/</font>
00080
00081 <font class="keywordtype">int</font> GDALGetCacheMax()<font class="keyword"></font>
00082 <font class="keyword"></font>{
00083 <font class="keywordflow">if</font>( !bCacheMaxInitialized )
00084 {
00085 <font class="keywordflow">if</font>( getenv(<font class="stringliteral">"GDAL_CACHEMAX"</font>) != NULL )
00086 {
00087 nCacheMax = atoi(getenv(<font class="stringliteral">"GDAL_CACHEMAX"</font>));
00088 <font class="keywordflow">if</font>( nCacheMax < 1000 )
00089 nCacheMax *= 1024 * 1024;
00090 }
00091 bCacheMaxInitialized = TRUE;
00092 }
00093
00094 <font class="keywordflow">return</font> nCacheMax;
00095 }
00096
00097 <font class="comment">/************************************************************************/</font>
00098 <font class="comment">/* GDALGetCacheUsed() */</font>
00099 <font class="comment">/************************************************************************/</font>
00100
00101 <font class="keywordtype">int</font> GDALGetCacheUsed()<font class="keyword"></font>
00102 <font class="keyword"></font>{
00103 <font class="keywordflow">return</font> nCacheUsed;
00104 }
00105
00106 <font class="comment">/************************************************************************/</font>
00107 <font class="comment">/* GDALFlushCacheBlock() */</font>
00108 <font class="comment">/* */</font>
00109 <font class="comment">/* The workhorse of cache management! */</font>
00110 <font class="comment">/************************************************************************/</font>
00111
00112 <font class="keywordtype">int</font> GDALFlushCacheBlock()<font class="keyword"></font>
00113 <font class="keyword"></font>
00114 <font class="keyword"></font>{
00115 <font class="keywordflow">if</font>( poOldest == NULL )
00116 <font class="keywordflow">return</font> FALSE;
00117 poOldest->GetBand()->FlushBlock( poOldest->GetXOff(),
00118 poOldest->GetYOff() );
00119
00120 <font class="keywordflow">return</font> TRUE;
00121 }
00122
00123 <font class="comment">/************************************************************************/</font>
00124 <font class="comment">/* GDALRasterBand() */</font>
00125 <font class="comment">/************************************************************************/</font>
00126
00127 GDALRasterBlock::GDALRasterBlock( <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> *poBandIn,
00128 <font class="keywordtype">int</font> nXOffIn, <font class="keywordtype">int</font> nYOffIn )<font class="keyword"></font>
00129 <font class="keyword"></font>
00130 <font class="keyword"></font>{
00131 poBand = poBandIn;
00132
00133 poBand-><a class="code" href="class_GDALRasterBand.html#a6">GetBlockSize</a>( &nXSize, &nYSize );
00134 eType = poBand-><a class="code" href="class_GDALRasterBand.html#a5">GetRasterDataType</a>();
00135 pData = NULL;
00136 bDirty = FALSE;
00137
00138 poNext = poPrevious = NULL;
00139
00140 nXOff = nXOffIn;
00141 nYOff = nYOffIn;
00142 }
00143
00144 <font class="comment">/************************************************************************/</font>
00145 <font class="comment">/* ~GDALRasterBlock() */</font>
00146 <font class="comment">/************************************************************************/</font>
00147
00148 GDALRasterBlock::~GDALRasterBlock()<font class="keyword"></font>
00149 <font class="keyword"></font>
00150 <font class="keyword"></font>{
00151 <font class="keywordflow">if</font>( pData != NULL )
00152 {
00153 <font class="keywordtype">int</font> nSizeInBytes;
00154
00155 VSIFree( pData );
00156
00157 nSizeInBytes = (nXSize * nYSize * GDALGetDataTypeSize(eType)+7)/8;
00158 nCacheUsed -= nSizeInBytes;
00159 }
00160
00161 <font class="keywordflow">if</font>( poOldest == <font class="keyword">this</font> )
00162 poOldest = poPrevious;
00163
00164 <font class="keywordflow">if</font>( poNewest == <font class="keyword">this</font> )
00165 {
00166 poNewest = poNext;
00167 }
00168
00169 <font class="keywordflow">if</font>( poPrevious != NULL )
00170 poPrevious->poNext = poNext;
00171
00172 <font class="keywordflow">if</font>( poNext != NULL )
00173 poNext->poPrevious = poPrevious;
00174
00175 <font class="preprocessor">#ifdef ENABLE_DEBUG</font>
00176 <font class="preprocessor"></font> Verify();
00177 <font class="preprocessor">#endif</font>
00178 <font class="preprocessor"></font>
00179 nAge = -1;
00180 }
00181
00182 <font class="comment">/************************************************************************/</font>
00183 <font class="comment">/* Verify() */</font>
00184 <font class="comment">/************************************************************************/</font>
00185
00186 <font class="keywordtype">void</font> GDALRasterBlock::Verify()<font class="keyword"></font>
00187 <font class="keyword"></font>
00188 <font class="keyword"></font>{
00189 CPLAssert( (poNewest == NULL && poOldest == NULL)
00190 || (poNewest != NULL && poOldest != NULL) );
00191
00192 <font class="keywordflow">if</font>( poNewest != NULL )
00193 {
00194 CPLAssert( poNewest->poPrevious == NULL );
00195 CPLAssert( poOldest->poNext == NULL );
00196
00197
00198 <font class="keywordflow">for</font>( <a class="code" href="class_GDALRasterBlock.html">GDALRasterBlock</a> *poBlock = poNewest;
00199 poBlock != NULL;
00200 poBlock = poBlock->poNext )
00201 {
00202 <font class="keywordflow">if</font>( poBlock->poPrevious )
00203 {
00204 CPLAssert( poBlock->poPrevious->poNext == poBlock );
00205 }
00206
00207 <font class="keywordflow">if</font>( poBlock->poNext )
00208 {
00209 CPLAssert( poBlock->poNext->poPrevious == poBlock );
00210 }
00211 }
00212 }
00213 }
00214
00215 <font class="comment">/************************************************************************/</font>
00216 <font class="comment">/* Write() */</font>
00217 <font class="comment">/************************************************************************/</font>
00218
00219 CPLErr GDALRasterBlock::Write()<font class="keyword"></font>
00220 <font class="keyword"></font>
00221 <font class="keyword"></font>{
00222 <font class="keywordflow">if</font>( !GetDirty() )
00223 <font class="keywordflow">return</font> CE_None;
00224
00225 <font class="keywordflow">if</font>( poBand == NULL )
00226 <font class="keywordflow">return</font> CE_Failure;
00227
00228 MarkClean();
00229
00230 <font class="keywordflow">return</font> poBand-><a class="code" href="class_GDALRasterBand.html#b1">IWriteBlock</a>( nXOff, nYOff, pData );
00231 }
00232
00233 <font class="comment">/************************************************************************/</font>
00234 <font class="comment">/* Touch() */</font>
00235 <font class="comment">/************************************************************************/</font>
00236
00237 <font class="keywordtype">void</font> GDALRasterBlock::Touch()<font class="keyword"></font>
00238 <font class="keyword"></font>
00239 <font class="keyword"></font>{
00240 nAge = nTileAgeTicker++;
00241
00242 <font class="keywordflow">if</font>( poNewest == <font class="keyword">this</font> )
00243 <font class="keywordflow">return</font>;
00244
00245 <font class="keywordflow">if</font>( poOldest == <font class="keyword">this</font> )
00246 poOldest = this->poPrevious;
00247
00248 <font class="keywordflow">if</font>( poPrevious != NULL )
00249 poPrevious->poNext = poNext;
00250
00251 <font class="keywordflow">if</font>( poNext != NULL )
00252 poNext->poPrevious = poPrevious;
00253
00254 poPrevious = NULL;
00255 poNext = poNewest;
00256
00257 <font class="keywordflow">if</font>( poNewest != NULL )
00258 {
00259 CPLAssert( poNewest->poPrevious == NULL );
00260 poNewest->poPrevious = <font class="keyword">this</font>;
00261 }
00262 poNewest = <font class="keyword">this</font>;
00263
00264 <font class="keywordflow">if</font>( poOldest == NULL )
00265 {
00266 CPLAssert( poPrevious == NULL && poNext == NULL );
00267 poOldest = <font class="keyword">this</font>;
00268 }
00269 <font class="preprocessor">#ifdef ENABLE_DEBUG</font>
00270 <font class="preprocessor"></font> Verify();
00271 <font class="preprocessor">#endif</font>
00272 <font class="preprocessor"></font>}
00273
00274 <font class="comment">/************************************************************************/</font>
00275 <font class="comment">/* Internalize() */</font>
00276 <font class="comment">/************************************************************************/</font>
00277
00278 CPLErr GDALRasterBlock::Internalize()<font class="keyword"></font>
00279 <font class="keyword"></font>
00280 <font class="keyword"></font>{
00281 <font class="keywordtype">void</font> *pNewData;
00282 <font class="keywordtype">int</font> nSizeInBytes;
00283 <font class="keywordtype">int</font> nCurCacheMax = GDALGetCacheMax();
00284
00285 nSizeInBytes = nXSize * nYSize * (GDALGetDataTypeSize(eType) / 8);
00286
00287 pNewData = VSIMalloc( nSizeInBytes );
00288 <font class="keywordflow">if</font>( pNewData == NULL )
00289 <font class="keywordflow">return</font>( CE_Failure );
00290
00291 <font class="keywordflow">if</font>( pData != NULL )
00292 memcpy( pNewData, pData, nSizeInBytes );
00293
00294 pData = pNewData;
00295
00296 <font class="comment">/* -------------------------------------------------------------------- */</font>
00297 <font class="comment">/* Flush old blocks if we are nearing our memory limit. */</font>
00298 <font class="comment">/* -------------------------------------------------------------------- */</font>
00299 nCacheUsed += nSizeInBytes;
00300 <font class="keywordflow">while</font>( nCacheUsed > nCurCacheMax )
00301 {
00302 <font class="keywordtype">int</font> nOldCacheUsed = nCacheUsed;
00303
00304 GDALFlushCacheBlock();
00305
00306 <font class="keywordflow">if</font>( nCacheUsed == nOldCacheUsed )
00307 {
00308 <font class="keyword">static</font> <font class="keywordtype">int</font> bReported = FALSE;
00309
00310 <font class="keywordflow">if</font>( !bReported )
00311 {
00312 bReported = TRUE;
00313 }
00314 <font class="keywordflow">break</font>;
00315 }
00316 }
00317
00318 <font class="comment">/* -------------------------------------------------------------------- */</font>
00319 <font class="comment">/* Add this block to the list. */</font>
00320 <font class="comment">/* -------------------------------------------------------------------- */</font>
00321 Touch();
00322 <font class="keywordflow">return</font>( CE_None );
00323 }
00324
00325 <font class="comment">/************************************************************************/</font>
00326 <font class="comment">/* MarkDirty() */</font>
00327 <font class="comment">/************************************************************************/</font>
00328
00329 <font class="keywordtype">void</font> GDALRasterBlock::MarkDirty()<font class="keyword"></font>
00330 <font class="keyword"></font>
00331 <font class="keyword"></font>{
00332 bDirty = TRUE;
00333 }
00334
00335
00336 <font class="comment">/************************************************************************/</font>
00337 <font class="comment">/* MarkClean() */</font>
00338 <font class="comment">/************************************************************************/</font>
00339
00340 <font class="keywordtype">void</font> GDALRasterBlock::MarkClean()<font class="keyword"></font>
00341 <font class="keyword"></font>
00342 <font class="keyword"></font>{
00343 bDirty = FALSE;
00344 }
00345
00346
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