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C:/temp/src/j2k/Beta/JString.c

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#ifndef __J2K__JSTRING_C__
#define __J2K__JSTRING_C__

/*
http://www.cygnus.com/~manfredh/libgxx/libg++-2.8.1.3.tar.gz
http://www.europe.redhat.com/documentation/HOWTO/C++Programming-HOWTO-15.php3
http://www.mike95.com/c_plusplus/classes/JString/

This new version of JString 
is an enhanced and more optimized version 
based on libg++ 2.8.1.3 string algorithm
which is also LGPL licensed.

Copyright (C) 1988 Free Software Foundation - LGPL licensed.
written by Doug Lea (dl@rocky.oswego.edu)

Refer to license.txt for the complete LGPL license documentation.
*/

#include <j2k/Fred/fast_alloc.c>

 /* Internal String representations */
typedef struct _JString_t   
{
  size_t   bufferSize;   /* Allocated Buffer Space                         */
  size_t   length;       /* The Actual String Length                       */
  short    nbRefs;       /* Reference Counter                              */
  char     lock;         /* Lock, if direct access (CString compatibility) */

  char     data[1];      /* The string is at least '\0', so one null byte  */
                         /* It must be allocated/expanded via realloc()    */
} JString_t;


typedef struct _JSubString_t
{
  size_t         pos;    /* Starting position of the string in rep         */
  size_t         len;    /* Length of the substring                        */
  JString_t*     str;    /* The String I'm a substring of                  */
 _JSubString_t*  next;   /* For a link-list of JString parts...            */

} JSubString_t;

#define JSTRING_SIZE     ( sizeof( JString_t    ) )
#define JSUBSTRING_SIZE  ( sizeof( JSubString_t ) )

#define JSTRING_INIT     { 0, 0, 1, 0, { 0 } }
#define JSUBSTRING_INIT  { 0, 0, 0, 0 }


/* Primitive operations on JString_t -- nearly all JString functions use those. */

JString_t* JString_malloc( register size_t  buffer_size )
{
  buffer_size += sizeof( JString_t );
  return (JString_t*)fast_malloc( buffer_size );
}

JString_t* JString_calloc( register size_t  buffer_size )
{
  buffer_size += sizeof( JString_t );
  JString_t* s = (JString_t*)fast_malloc( buffer_size );
  memset( s, 0, buffer_size );
  s->nbRefs = 1;
  return s;
}

void JString_free( JString_t* this )
{
  /* delete if not used and unlock */
  if( --this->nbRefs <= 0  &&  this->lock == 0 )
  {
    free( this );
  }
}

/* GOTCHA: We assume length is passed as: strlen( str ) if unknown */
JString_t* JString_create( const char* str, register size_t length, register size_t  buffer_size )
{
  /* Make sure the buffer size is at least the length */
  if ( buffer_size < length ) 
  {
    buffer_size = length;
  }

  JString_t* s = JString_calloc( buffer_size );

  if ( str != NULL )
  {
    memcpy( s->data, str, length );
  }

  return s;
}

JString_t* JString_safe_create( const char* str )
{
  return JString_create( str, strlen( str ), 80 ); 
}

#endif

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