cplconv.cpp

国际海图标准S-57格式数据读取源码VC

#include "stdafx.h"
#include "CplConv.h"
#include "CplString.h"

static char **papszConfigOptions = NULL;

/************************************************************************/
/*                             CPLCalloc()                              */
/************************************************************************/

/**
 * Safe version of calloc().
 *
 * This function is like the C library calloc(), but raises a CE_Fatal
 * error with CPLError() if it fails to allocate the desired memory.  It
 * should be used for small memory allocations that are unlikely to fail
 * and for which the application is unwilling to test for out of memory
 * conditions.  It uses VSICalloc() to get the memory, so any hooking of
 * VSICalloc() will apply to CPLCalloc() as well.  CPLFree() or VSIFree()
 * can be used free memory allocated by CPLCalloc().
 *
 * @param nCount number of objects to allocate.
 * @param nSize size (in bytes) of object to allocate.
 * @return pointer to newly allocated memory, only NULL if nSize * nCount is
 * NULL.
 */

void *CPLCalloc( size_t nCount, size_t nSize )

{
    void        *pReturn;

    if( nSize * nCount == 0 )
        return NULL;
    
    pReturn = VSICalloc( nCount, nSize );
    if( pReturn == NULL )
    {
        CPLError( CE_Fatal, CPLE_OutOfMemory,
                  "CPLCalloc(): Out of memory allocating %d bytes.\n",
                  nSize * nCount );
    }

    return pReturn;
}

/************************************************************************/
/*                             CPLMalloc()                              */
/************************************************************************/

/**
 * Safe version of malloc().
 *
 * This function is like the C library malloc(), but raises a CE_Fatal
 * error with CPLError() if it fails to allocate the desired memory.  It
 * should be used for small memory allocations that are unlikely to fail
 * and for which the application is unwilling to test for out of memory
 * conditions.  It uses VSIMalloc() to get the memory, so any hooking of
 * VSIMalloc() will apply to CPLMalloc() as well.  CPLFree() or VSIFree()
 * can be used free memory allocated by CPLMalloc().
 *
 * @param nSize size (in bytes) of memory block to allocate.
 * @return pointer to newly allocated memory, only NULL if nSize is zero.
 */

void *CPLMalloc( size_t nSize )

{
    void        *pReturn;

    CPLVerifyConfiguration();

    if( nSize == 0 )
        return NULL;
    
    pReturn = VSIMalloc( nSize );
    if( pReturn == NULL )
    {
        CPLError( CE_Fatal, CPLE_OutOfMemory,
                  "CPLMalloc(): Out of memory allocating %d bytes.\n",
                  nSize );
    }

    return pReturn;
}

/************************************************************************/
/*                             CPLRealloc()                             */
/************************************************************************/

/**
 * Safe version of realloc().
 *
 * This function is like the C library realloc(), but raises a CE_Fatal
 * error with CPLError() if it fails to allocate the desired memory.  It
 * should be used for small memory allocations that are unlikely to fail
 * and for which the application is unwilling to test for out of memory
 * conditions.  It uses VSIRealloc() to get the memory, so any hooking of
 * VSIRealloc() will apply to CPLRealloc() as well.  CPLFree() or VSIFree()
 * can be used free memory allocated by CPLRealloc().
 *
 * It is also safe to pass NULL in as the existing memory block for
 * CPLRealloc(), in which case it uses VSIMalloc() to allocate a new block.
 *
 * @param pData existing memory block which should be copied to the new block.
 * @param nNewSize new size (in bytes) of memory block to allocate.
 * @return pointer to allocated memory, only NULL if nNewSize is zero.
 */


void * CPLRealloc( void * pData, size_t nNewSize )

{
    void        *pReturn;

    if ( nNewSize == 0 )
    {
        VSIFree(pData);
        return NULL;
    }

    if( pData == NULL )
        pReturn = VSIMalloc( nNewSize );
    else
        pReturn = VSIRealloc( pData, nNewSize );
    
    if( pReturn == NULL )
    {
        CPLError( CE_Fatal, CPLE_OutOfMemory,
                  "CPLRealloc(): Out of memory allocating %d bytes.\n",
                  nNewSize );
    }

    return pReturn;
}

/************************************************************************/
/*                             CPLStrdup()                              */
/************************************************************************/

/**
 * Safe version of strdup() function.
 *
 * This function is similar to the C library strdup() function, but if
 * the memory allocation fails it will issue a CE_Fatal error with
 * CPLError() instead of returning NULL.  It uses VSIStrdup(), so any
 * hooking of that function will apply to CPLStrdup() as well.  Memory
 * allocated with CPLStrdup() can be freed with CPLFree() or VSIFree().
 *
 * It is also safe to pass a NULL string into CPLStrdup().  CPLStrdup()
 * will allocate and return a zero length string (as opposed to a NULL
 * string).
 *
 * @param pszString input string to be duplicated.  May be NULL.
 * @return pointer to a newly allocated copy of the string.  Free with
 * CPLFree() or VSIFree().
 */

char *CPLStrdup( const char * pszString )

{
    char        *pszReturn;

    if( pszString == NULL )
        pszString = "";

    pszReturn = VSIStrdup( pszString );
        
    if( pszReturn == NULL )
    {
        CPLError( CE_Fatal, CPLE_OutOfMemory,
                  "CPLStrdup(): Out of memory allocating %d bytes.\n",
                  strlen(pszString) );
        
    }
    
    return( pszReturn );
}

/************************************************************************/
/*                              CPLFGets()                              */
/*                                                                      */
/*      Note: CR = \r = ASCII 13                                        */
/*            LF = \n = ASCII 10                                        */
/************************************************************************/

/**
 * Reads in at most one less than nBufferSize characters from the fp
 * stream and stores them into the buffer pointed to by pszBuffer.
 * Reading stops after an EOF or a newline. If a newline is read, it
 * is _not_ stored into the buffer. A '\0' is stored after the last
 * character in the buffer. All three types of newline terminators
 * recognized by the CPLFGets(): single '\r' and '\n' and '\r\n'
 * combination.
 *
 * @param pszBuffer pointer to the targeting character buffer.
 * @param nBufferSize maximum size of the string to read (not including
 * termonating '\0').
 * @param fp file pointer to read from.
 * @return pointer to the pszBuffer containing a string read
 * from the file or NULL if the error or end of file was encountered.
 */

char *CPLFGets( char *pszBuffer, int nBufferSize, FILE * fp )

{
    int nActuallyRead, nOriginalOffset;

    if ( nBufferSize == 0 || pszBuffer == NULL || fp == NULL )
	return NULL;

/* -------------------------------------------------------------------- */
/*      Let the OS level call read what it things is one line.  This    */
/*      will include the newline.  On windows, if the file happens      */
/*      to be in text mode, the CRLF will have been converted to        */
/*      just the newline (LF).  If it is in binary mode it may well     */
/*      have both.                                                      */
/* -------------------------------------------------------------------- */
    nOriginalOffset = VSIFTell( fp );
    if( VSIFGets( pszBuffer, nBufferSize, fp ) == NULL )
        return NULL;
    
    nActuallyRead = strlen(pszBuffer);
    if ( nActuallyRead == 0 )
	return NULL;

/* -------------------------------------------------------------------- */
/*      Trim off \n, \r or \r\n if it appears at the end.  We don't     */
/*      need to do any "seeking" since we want the newline eaten.       */
/* -------------------------------------------------------------------- */
    if( nActuallyRead > 1 
        && pszBuffer[nActuallyRead-1] == 10 
        && pszBuffer[nActuallyRead-2] == 13 )
    {
        pszBuffer[nActuallyRead-2] = '\0';
    }
    else if( pszBuffer[nActuallyRead-1] == 10 
             || pszBuffer[nActuallyRead-1] == 13 )
    {
        pszBuffer[nActuallyRead-1] = '\0';
    }

/* -------------------------------------------------------------------- */
/*      Search within the string for a \r (MacOS convention             */
/*      apparently), and if we find it we need to trim the string,      */
/*      and seek back.                                                  */
/* -------------------------------------------------------------------- */
    char *pszExtraNewline = strchr( pszBuffer, 13 );
    
    if( pszExtraNewline != NULL )
    {
        int chCheck;

        nActuallyRead = pszExtraNewline - pszBuffer + 1;
        
        *pszExtraNewline = '\0';
        VSIFSeek( fp, nOriginalOffset + nActuallyRead - 1, SEEK_SET );

        /* 
         * This hackery is necessary to try and find our correct
         * spot on win32 systems with text mode line translation going 
         * on.  Sometimes the fseek back overshoots, but it doesn't
         * "realize it" till a character has been read. Try to read till
         * we get to the right spot and get our CR. 
         */ 
        chCheck = fgetc( fp );
        while( (chCheck != 13 && chCheck != EOF)
               || VSIFTell(fp) < nOriginalOffset + nActuallyRead )
        {
            static int bWarned = FALSE;

            if( !bWarned )
            {
                bWarned = TRUE;
                CPLDebug( "CPL", "CPLFGets() correcting for DOS text mode translation seek problem." );
            }
            chCheck = fgetc( fp );
        }
    }

    return pszBuffer;
}

/************************************************************************/
/*                            CPLReadLine()                             */
/************************************************************************/

/**
 * Simplified line reading from text file.
 * 
 * Read a line of text from the given file handle, taking care
 * to capture CR and/or LF and strip off ... equivelent of
 * DKReadLine().  Pointer to an internal buffer is returned.
 * The application shouldn't free it, or depend on it's value
 * past the next call to CPLReadLine().
 * 
 * Note that CPLReadLine() uses VSIFGets(), so any hooking of VSI file
 * services should apply to CPLReadLine() as well.
 *
 * CPLReadLine() maintains an internal buffer, which will appear as a 
 * single block memory leak in some circumstances.  CPLReadLine() may 
 * be called with a NULL FILE * at any time to free this working buffer.
 *
 * @param fp file pointer opened with VSIFOpen().
 *
 * @return pointer to an internal buffer containing a line of text read
 * from the file or NULL if the end of file was encountered.
 */

const char *CPLReadLine( FILE * fp )

{
    static char *pszRLBuffer = NULL;
    static int  nRLBufferSize = 0;
    int         nReadSoFar = 0;

/* -------------------------------------------------------------------- */
/*      Cleanup case.                                                   */
/* -------------------------------------------------------------------- */
    if( fp == NULL )
    {
        CPLFree( pszRLBuffer );
        pszRLBuffer = NULL;
        nRLBufferSize = 0;
        return NULL;
    }

/* -------------------------------------------------------------------- */
/*      Loop reading chunks of the line till we get to the end of       */
/*      the line.                                                       */
/* -------------------------------------------------------------------- */
    do {
/* -------------------------------------------------------------------- */
/*      Grow the working buffer if we have it nearly full.  Fail out    */
/*      of read line if we can't reallocate it big enough (for          */
/*      instance for a _very large_ file with no newlines).             */
/* -------------------------------------------------------------------- */
        if( nRLBufferSize-nReadSoFar < 128 )
        {
            nRLBufferSize = nRLBufferSize*2 + 128;
            pszRLBuffer = (char *) VSIRealloc(pszRLBuffer, nRLBufferSize);
            if( pszRLBuffer == NULL )
            {
                nRLBufferSize = 0;
                return NULL;
            }
        }

/* -------------------------------------------------------------------- */
/*      Do the actual read.                                             */
/* -------------------------------------------------------------------- */
        if( CPLFGets( pszRLBuffer+nReadSoFar, nRLBufferSize-nReadSoFar, fp )
            == NULL )
        {
            CPLFree( pszRLBuffer );
            pszRLBuffer = NULL;
            nRLBufferSize = 0;

            return NULL;
        }

        nReadSoFar = strlen(pszRLBuffer);

    } while( nReadSoFar == nRLBufferSize - 1
             && pszRLBuffer[nRLBufferSize-2] != 13
             && pszRLBuffer[nRLBufferSize-2] != 10 );

    return( pszRLBuffer );
}

/************************************************************************/
/*                            CPLScanString()                           */
/************************************************************************/

/**
 * Scan up to a maximum number of characters from a given string,
 * allocate a buffer for a new string and fill it with scanned characters.
 *
 * @param pszString String containing characters to be scanned. It may be
 * terminated with a null character.
 *
 * @param nMaxLength The maximum number of character to read. Less
 * characters will be read if a null character is encountered.
 *
 * @param bTrimSpaces If TRUE, trim ending spaces from the input string.
 * Character considered as empty using isspace(3) function.
 *
 * @param bNormalize If TRUE, replace ':' symbol with the '_'. It is needed if
 * resulting string will be used in CPL dictionaries.
 * 
 * @return Pointer to the resulting string buffer. Caller responsible to free
 * this buffer with CPLFree().
 */

char *CPLScanString( char *pszString, int nMaxLength,
                     int bTrimSpaces, int bNormalize )
{
    char    *pszBuffer;

    if ( !pszString )
        return NULL;

    if ( !nMaxLength )
        return CPLStrdup( "" );