/****************************************************************************** * * Project: ISO 8211 Access * Purpose: Implements the DDFField class. * Author: Frank Warmerdam, warmerdam@pobox.com * ****************************************************************************** * Copyright (c) 1999, Frank Warmerdam * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included * in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER * DEALINGS IN THE SOFTWARE. ****************************************************************************/ #include "cpl_port.h" #include "iso8211.h" #include #include #include #include "cpl_conv.h" CPL_CVSID("$Id: ddffield.cpp 7e07230bbff24eb333608de4dbd460b7312839d0 2017-12-11 19:08:47Z Even Rouault $") // Note, we implement no constructor for this class to make instantiation // cheaper. It is required that the Initialize() be called before anything // else. /************************************************************************/ /* Initialize() */ /************************************************************************/ void DDFField::Initialize( DDFFieldDefn *poDefnIn, const char * pachDataIn, int nDataSizeIn ) { pachData = pachDataIn; nDataSize = nDataSizeIn; poDefn = poDefnIn; } /************************************************************************/ /* Dump() */ /************************************************************************/ /** * Write out field contents to debugging file. * * A variety of information about this field, and all its * subfields is written to the given debugging file handle. Note that * field definition information (ala DDFFieldDefn) isn't written. * * @param fp The standard IO file handle to write to. i.e. stderr */ void DDFField::Dump( FILE * fp ) { int nMaxRepeat = 8; if( getenv("DDF_MAXDUMP") != nullptr ) nMaxRepeat = atoi(getenv("DDF_MAXDUMP")); fprintf( fp, " DDFField:\n" ); fprintf( fp, " Tag = `%s'\n", poDefn->GetName() ); fprintf( fp, " DataSize = %d\n", nDataSize ); fprintf( fp, " Data = `" ); for( int i = 0; i < std::min(nDataSize, 40); i++ ) { if( pachData[i] < 32 || pachData[i] > 126 ) fprintf( fp, "\\%02X", ((unsigned char *) pachData)[i] ); else fprintf( fp, "%c", pachData[i] ); } if( nDataSize > 40 ) fprintf( fp, "..." ); fprintf( fp, "'\n" ); /* -------------------------------------------------------------------- */ /* dump the data of the subfields. */ /* -------------------------------------------------------------------- */ int iOffset = 0; for( int nLoopCount = 0; nLoopCount < GetRepeatCount(); nLoopCount++ ) { if( nLoopCount > nMaxRepeat ) { fprintf( fp, " ...\n" ); break; } for( int i = 0; i < poDefn->GetSubfieldCount(); i++ ) { poDefn->GetSubfield(i)->DumpData( pachData + iOffset, nDataSize - iOffset, fp ); int nBytesConsumed = 0; poDefn->GetSubfield(i)->GetDataLength( pachData + iOffset, nDataSize - iOffset, &nBytesConsumed ); iOffset += nBytesConsumed; } } } /************************************************************************/ /* GetSubfieldData() */ /************************************************************************/ /** * Fetch raw data pointer for a particular subfield of this field. * * The passed DDFSubfieldDefn (poSFDefn) should be acquired from the * DDFFieldDefn corresponding with this field. This is normally done * once before reading any records. This method involves a series of * calls to DDFSubfield::GetDataLength() in order to track through the * DDFField data to that belonging to the requested subfield. This can * be relatively expensive.

* * @param poSFDefn The definition of the subfield for which the raw * data pointer is desired. * @param pnMaxBytes The maximum number of bytes that can be accessed from * the returned data pointer is placed in this int, unless it is NULL. * @param iSubfieldIndex The instance of this subfield to fetch. Use zero * (the default) for the first instance. * * @return A pointer into the DDFField's data that belongs to the subfield. * This returned pointer is invalidated by the next record read * (DDFRecord::ReadRecord()) and the returned pointer should not be freed * by the application. */ const char *DDFField::GetSubfieldData( DDFSubfieldDefn *poSFDefn, int *pnMaxBytes, int iSubfieldIndex ) { if( poSFDefn == nullptr ) return nullptr; int iOffset = 0; if( iSubfieldIndex > 0 && poDefn->GetFixedWidth() > 0 ) { iOffset = poDefn->GetFixedWidth() * iSubfieldIndex; iSubfieldIndex = 0; } while( iSubfieldIndex >= 0 ) { for( int iSF = 0; iSF < poDefn->GetSubfieldCount(); iSF++ ) { DDFSubfieldDefn * poThisSFDefn = poDefn->GetSubfield( iSF ); if( nDataSize < iOffset ) { CPLError(CE_Failure, CPLE_AppDefined, "Invalid data size for subfield %s of %s", poThisSFDefn->GetName(), poDefn->GetName()); return nullptr; } if( poThisSFDefn == poSFDefn && iSubfieldIndex == 0 ) { if( pnMaxBytes != nullptr ) *pnMaxBytes = nDataSize - iOffset; return pachData + iOffset; } int nBytesConsumed = 0; poThisSFDefn->GetDataLength( pachData+iOffset, nDataSize - iOffset, &nBytesConsumed); iOffset += nBytesConsumed; } iSubfieldIndex--; } // We didn't find our target subfield or instance! return nullptr; } /************************************************************************/ /* GetRepeatCount() */ /************************************************************************/ /** * How many times do the subfields of this record repeat? This * will always be one for non-repeating fields. * * @return The number of times that the subfields of this record occur * in this record. This will be one for non-repeating fields. * * @see 8211view example program * for a demonstration of handling repeated fields properly. */ int DDFField::GetRepeatCount() { if( !poDefn->IsRepeating() ) return 1; /* -------------------------------------------------------------------- */ /* The occurrence count depends on how many copies of this */ /* field's list of subfields can fit into the data space. */ /* -------------------------------------------------------------------- */ if( poDefn->GetFixedWidth() ) { return nDataSize / poDefn->GetFixedWidth(); } /* -------------------------------------------------------------------- */ /* Note that it may be legal to have repeating variable width */ /* subfields, but I don't have any samples, so I ignore it for */ /* now. */ /* */ /* The file data/cape_royal_AZ_DEM/1183XREF.DDF has a repeating */ /* variable length field, but the count is one, so it isn't */ /* much value for testing. */ /* -------------------------------------------------------------------- */ int iOffset = 0; int iRepeatCount = 1; while( true ) { const int iOffsetBefore = iOffset; for( int iSF = 0; iSF < poDefn->GetSubfieldCount(); iSF++ ) { DDFSubfieldDefn * poThisSFDefn = poDefn->GetSubfield( iSF ); int nBytesConsumed = 0; if( poThisSFDefn->GetWidth() > nDataSize - iOffset ) nBytesConsumed = poThisSFDefn->GetWidth(); else poThisSFDefn->GetDataLength( pachData+iOffset, nDataSize - iOffset, &nBytesConsumed); iOffset += nBytesConsumed; if( iOffset > nDataSize ) return iRepeatCount - 1; } if( iOffset == iOffsetBefore ) { // Should probably emit error return iRepeatCount - 1; } if( iOffset > nDataSize - 2 ) return iRepeatCount; iRepeatCount++; } } /************************************************************************/ /* GetInstanceData() */ /************************************************************************/ /** * Get field instance data and size. * * The returned data pointer and size values are suitable for use with * DDFRecord::SetFieldRaw(). * * @param nInstance a value from 0 to GetRepeatCount()-1. * @param pnInstanceSize a location to put the size (in bytes) of the * field instance data returned. This size will include the unit terminator * (if any), but not the field terminator. This size pointer may be NULL * if not needed. * * @return the data pointer, or NULL on error. */ const char *DDFField::GetInstanceData( int nInstance, int *pnInstanceSize ) { int nRepeatCount = GetRepeatCount(); if( nInstance < 0 || nInstance >= nRepeatCount ) return nullptr; /* -------------------------------------------------------------------- */ /* Special case for fields without subfields (like "0001"). We */ /* don't currently handle repeating simple fields. */ /* -------------------------------------------------------------------- */ if( poDefn->GetSubfieldCount() == 0 ) { const char *pachWrkData = GetData(); if( pnInstanceSize != nullptr ) *pnInstanceSize = GetDataSize(); return pachWrkData; } /* -------------------------------------------------------------------- */ /* Get a pointer to the start of the existing data for this */ /* iteration of the field. */ /* -------------------------------------------------------------------- */ int nBytesRemaining1 = 0; int nBytesRemaining2 = 0; DDFSubfieldDefn *poFirstSubfield = poDefn->GetSubfield(0); const char *pachWrkData = GetSubfieldData(poFirstSubfield, &nBytesRemaining1, nInstance); if( pachWrkData == nullptr ) return nullptr; /* -------------------------------------------------------------------- */ /* Figure out the size of the entire field instance, including */ /* unit terminators, but not any trailing field terminator. */ /* -------------------------------------------------------------------- */ if( pnInstanceSize != nullptr ) { DDFSubfieldDefn *poLastSubfield = poDefn->GetSubfield(poDefn->GetSubfieldCount()-1); const char *pachLastData = GetSubfieldData( poLastSubfield, &nBytesRemaining2, nInstance ); if( pachLastData == nullptr ) return nullptr; int nLastSubfieldWidth = 0; poLastSubfield->GetDataLength( pachLastData, nBytesRemaining2, &nLastSubfieldWidth ); *pnInstanceSize = nBytesRemaining1 - (nBytesRemaining2 - nLastSubfieldWidth); } return pachWrkData; }