maplayer.c

/******************************************************************************
 * $Id$
 *
 * Project:  MapServer
 * Purpose:  Implementation of most layerObj functions.
 * Author:   Steve Lime and the MapServer team.
 *
 ******************************************************************************
 * Copyright (c) 1996-2005 Regents of the University of Minnesota.
 *
 * 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 of this Software or works derived from this 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 "mapserver.h"
#include "maptime.h"
#include "mapogcfilter.h"
#include "mapthread.h"
#include "mapfile.h"

#include "mapparser.h"

#include <assert.h>

static int populateVirtualTable(layerVTableObj *vtable);

/*
** Iteminfo is a layer parameter that holds information necessary to retrieve an individual item for
** a particular source. It is an array built from a list of items. The type of iteminfo will vary by
** source. For shapefiles and OGR it is simply an array of integers where each value is an index for
** the item. For SDE it's a ESRI specific type that contains index and column type information. Two
** helper functions below initialize and free that structure member which is used locally by layer
** specific functions.
*/
int msLayerInitItemInfo(layerObj *layer)
{
  if ( ! layer->vtable) {
    int rv =  msInitializeVirtualTable(layer);
    if (rv != MS_SUCCESS)
      return rv;
  }
  return layer->vtable->LayerInitItemInfo(layer);
}

void msLayerFreeItemInfo(layerObj *layer)
{
  if ( ! layer->vtable) {
    int rv =  msInitializeVirtualTable(layer);
    if (rv != MS_SUCCESS)
      return;
  }
  layer->vtable->LayerFreeItemInfo(layer);

  /*
   * Layer expressions with attribute binding hold a numeric index pointing
   * to an iteminfo (node->tokenval.bindval.index). If iteminfo changes,
   * an expression may be no longer valid. (#5161)
   */
  msLayerFreeExpressions(layer);
}

int msLayerRestoreFromScaletokens(layerObj *layer)
{
  if(!layer->scaletokens || !layer->orig_st) {
    return MS_SUCCESS;
  }
  if(layer->orig_st->data) {
    msFree(layer->data);
    layer->data = layer->orig_st->data;
  }
  if(layer->orig_st->tileindex) {
    msFree(layer->tileindex);
    layer->tileindex = layer->orig_st->tileindex;
  }
  if(layer->orig_st->tileitem) {
    msFree(layer->tileitem);
    layer->tileitem = layer->orig_st->tileitem;
  }
  if(layer->orig_st->filter) {
    msLoadExpressionString(&(layer->filter),layer->orig_st->filter);
    msFree(layer->orig_st->filter);
  }
  if(layer->orig_st->filteritem) {
    msFree(layer->filteritem);
    layer->filteritem = layer->orig_st->filteritem;
  }
  if(layer->orig_st->n_processing) {
    int i;
    for(i=0;i<layer->orig_st->n_processing;i++) {
      msFree(layer->processing[layer->orig_st->processing_idx[i]]);
      layer->processing[layer->orig_st->processing_idx[i]] = layer->orig_st->processing[i];
    }
    msFree(layer->orig_st->processing);
    msFree(layer->orig_st->processing_idx);
  }
  msFree(layer->orig_st);
  layer->orig_st = NULL;
  return MS_SUCCESS; 
}

#define check_st_alloc(l) if(!l->orig_st) l->orig_st=msSmallCalloc(1,sizeof(originalScaleTokenStrings));
int msLayerApplyScaletokens(layerObj *layer, double scale)
{
  int i,p;
  if(!layer->scaletokens) {
    return MS_SUCCESS;
  }
  msLayerRestoreFromScaletokens(layer);
  for(i=0;i<layer->numscaletokens;i++) {
    scaleTokenObj *st = &layer->scaletokens[i];
    scaleTokenEntryObj *ste = NULL;
    if(scale<=0) {
       ste = &(st->tokens[0]);
      /* no scale defined, use first entry */
    } else {
      int tokenindex=0;
      while(tokenindex<st->n_entries) {
        ste = &(st->tokens[tokenindex]);
        if(scale < ste->maxscale && scale >= ste->minscale) break; /* current token is the correct one */
        tokenindex++;
        ste = NULL;
      }
    }
    assert(ste);
    if(layer->data && strstr(layer->data,st->name)) {
      if(layer->debug >= MS_DEBUGLEVEL_DEBUG) {
        msDebug("replacing scaletoken (%s) with (%s) in layer->data (%s) for scale=%f\n",
                st->name,ste->value,layer->name,scale);
      }
      check_st_alloc(layer);
      layer->orig_st->data = layer->data;
      layer->data = msStrdup(layer->data);
      layer->data = msReplaceSubstring(layer->data,st->name,ste->value);
    }
    if(layer->tileindex && strstr(layer->tileindex,st->name)) {
      if(layer->debug >= MS_DEBUGLEVEL_DEBUG) {
        msDebug("replacing scaletoken (%s) with (%s) in layer->tileindex (%s) for scale=%f\n",
                st->name,ste->value,layer->name,scale);
      }
      check_st_alloc(layer);
      layer->orig_st->tileindex = layer->tileindex;
      layer->tileindex = msStrdup(layer->tileindex);
      layer->tileindex = msReplaceSubstring(layer->tileindex,st->name,ste->value);
    }
    if(layer->tileitem && strstr(layer->tileitem,st->name)) {
      if(layer->debug >= MS_DEBUGLEVEL_DEBUG) {
        msDebug("replacing scaletoken (%s) with (%s) in layer->tileitem (%s) for scale=%f\n",
                st->name,ste->value,layer->name,scale);
      }
      check_st_alloc(layer);
      layer->orig_st->tileitem = layer->tileitem;
      layer->tileitem = msStrdup(layer->tileitem);
      layer->tileitem = msReplaceSubstring(layer->tileitem,st->name,ste->value);
    }
    if(layer->filteritem && strstr(layer->filteritem,st->name)) {
      if(layer->debug >= MS_DEBUGLEVEL_DEBUG) {
        msDebug("replacing scaletoken (%s) with (%s) in layer->filteritem (%s) for scale=%f\n",
                st->name,ste->value,layer->name,scale);
      }
      check_st_alloc(layer);
      layer->orig_st->filteritem = layer->filteritem;
      layer->filteritem = msStrdup(layer->filteritem);
      layer->filteritem = msReplaceSubstring(layer->filteritem,st->name,ste->value);
    }
    if(layer->filter.string && strstr(layer->filter.string,st->name)) {
      char *tmpval;
      if(layer->debug >= MS_DEBUGLEVEL_DEBUG) {
        msDebug("replacing scaletoken (%s) with (%s) in layer->filter (%s) for scale=%f\n",
                st->name,ste->value,layer->name,scale);
      }
      check_st_alloc(layer);
      layer->orig_st->filter = msStrdup(layer->filter.string);
      tmpval = msStrdup(layer->filter.string);
      tmpval = msReplaceSubstring(tmpval,st->name,ste->value);
      if(msLoadExpressionString(&(layer->filter),tmpval) == -1) return(MS_FAILURE); /* msLoadExpressionString() cleans up previously allocated expression */
      msFree(tmpval);
    }
    for(p=0;p<layer->numprocessing;p++) {
      if(strstr(layer->processing[p],st->name)) {
        check_st_alloc(layer);
        layer->orig_st->n_processing++;
        layer->orig_st->processing = msSmallRealloc(layer->orig_st->processing, layer->orig_st->n_processing * sizeof(char*));
        layer->orig_st->processing_idx = msSmallRealloc(layer->orig_st->processing_idx, layer->orig_st->n_processing * sizeof(int));
        layer->orig_st->processing[layer->orig_st->n_processing-1] = layer->processing[p];
        layer->orig_st->processing_idx[layer->orig_st->n_processing-1] = p;
        layer->processing[p] = msStrdup(layer->processing[p]);
        layer->processing[p] = msReplaceSubstring(layer->processing[p],st->name,ste->value);
      }
    }

  }
  return MS_SUCCESS;
}


/*
** Does exactly what it implies, readies a layer for processing.
*/
int msLayerOpen(layerObj *layer)
{
  int rv;

  /* RFC-86 Scale dependant token replacements*/
  rv = msLayerApplyScaletokens(layer,(layer->map)?layer->map->scaledenom:-1);
  if (rv != MS_SUCCESS) return rv;

  /* RFC-69 clustering support */
  if (layer->cluster.region)
    return msClusterLayerOpen(layer);

  if(layer->features && layer->connectiontype != MS_GRATICULE )
    layer->connectiontype = MS_INLINE;

  if(layer->tileindex && layer->connectiontype == MS_SHAPEFILE)
    layer->connectiontype = MS_TILED_SHAPEFILE;

  if(layer->type == MS_LAYER_RASTER && layer->connectiontype != MS_WMS
      && layer->connectiontype != MS_KERNELDENSITY)
    layer->connectiontype = MS_RASTER;

  if ( ! layer->vtable) {
    rv =  msInitializeVirtualTable(layer);
    if (rv != MS_SUCCESS)
      return rv;
  }
  return layer->vtable->LayerOpen(layer);
}

/*
** Returns MS_TRUE if layer has been opened using msLayerOpen(), MS_FALSE otherwise
*/
int msLayerIsOpen(layerObj *layer)
{
  if ( ! layer->vtable) {
    int rv =  msInitializeVirtualTable(layer);
    if (rv != MS_SUCCESS)
      return rv;
  }
  return layer->vtable->LayerIsOpen(layer);
}

/*
** Returns MS_TRUE is a layer supports the common expression/filter syntax (RFC 64) and MS_FALSE otherwise.
*/
int msLayerSupportsCommonFilters(layerObj *layer)
{
  if ( ! layer->vtable) {
    int rv =  msInitializeVirtualTable(layer);
    if (rv != MS_SUCCESS)
      return rv;
  }
  return layer->vtable->LayerSupportsCommonFilters(layer);
}

int msLayerTranslateFilter(layerObj *layer, expressionObj *filter, char *filteritem)
{
  if (!layer->vtable) {
    int rv =  msInitializeVirtualTable(layer);
    if (rv != MS_SUCCESS)
      return rv;
  }
  return layer->vtable->LayerTranslateFilter(layer, filter, filteritem);
}

/*
** Performs a spatial, and optionally an attribute based feature search. The function basically
** prepares things so that candidate features can be accessed by query or drawing functions. For
** OGR and shapefiles this sets an internal bit vector that indicates whether a particular feature
** is to processed. For SDE it executes an SQL statement on the SDE server. Once run the msLayerNextShape
** function should be called to actually access the shapes.
**
** Note that for shapefiles we apply any maxfeatures constraint at this point. That may be the only
** connection type where this is feasible.
*/
int msLayerWhichShapes(layerObj *layer, rectObj rect, int isQuery)
{
  if(!msLayerSupportsCommonFilters(layer))
    msLayerTranslateFilter(layer, &layer->filter, layer->filteritem);

  if ( ! layer->vtable) {
    int rv =  msInitializeVirtualTable(layer);
    if (rv != MS_SUCCESS)
      return rv;
  }
  return layer->vtable->LayerWhichShapes(layer, rect, isQuery);
}

/*
** Called after msWhichShapes has been called to actually retrieve shapes within a given area
** and matching a vendor specific filter (i.e. layer FILTER attribute).
**
** Shapefiles: NULL shapes (shapes with attributes but NO vertices are skipped)
*/
int msLayerNextShape(layerObj *layer, shapeObj *shape)
{
  int rv, filter_passed;
  
  if ( ! layer->vtable) {
    rv =  msInitializeVirtualTable(layer);
    if (rv != MS_SUCCESS)
      return rv;
  }

#ifdef USE_V8_MAPSCRIPT
  /* we need to force the GetItems for the geomtransform attributes */
  if(!layer->items &&
     layer->_geomtransform.type == MS_GEOMTRANSFORM_EXPRESSION &&
     strstr(layer->_geomtransform.string, "javascript"))
      msLayerGetItems(layer);
#endif

  /* At the end of switch case (default -> break; -> return MS_FAILURE),
   * was following TODO ITEM:
   *
   * TO DO! This is where dynamic joins will happen. Joined attributes will be
   * tagged on to the main attributes with the naming scheme [join name].[item name].
   * We need to leverage the iteminfo (I think) at this point 
   */

  /* RFC 91: MapServer-based filtering is done at a more general level. */
  do {
    rv = layer->vtable->LayerNextShape(layer, shape);
    if(rv != MS_SUCCESS) return rv;

    filter_passed = MS_TRUE;  /* By default accept ANY shape */
    
    /* attributes need to be iconv'd to UTF-8 before any filter logic is applied */
    if(layer->encoding) {
      rv = msLayerEncodeShapeAttributes(layer,shape);
      if(rv != MS_SUCCESS)
        return rv;
    }
    
    // if(layer->numitems > 0 && layer->iteminfo) {
      filter_passed = msEvalExpression(layer, shape, &(layer->filter), layer->filteritemindex);
    // }

    if(!filter_passed) msFreeShape(shape);
  } while(!filter_passed);

  /* RFC89 Apply Layer GeomTransform */
  if(layer->_geomtransform.type != MS_GEOMTRANSFORM_NONE && rv == MS_SUCCESS) {
    rv = msGeomTransformShape(layer->map, layer, shape);      
    if(rv != MS_SUCCESS)
      return rv;
  }

  
  return rv;
}

/*
** Used to retrieve a shape from a result set by index. Result sets are created by the various
** msQueryBy...() functions. The index is assigned by the data source.
*/
/* int msLayerResultsGetShape(layerObj *layer, shapeObj *shape, int tile, long record)
{
  if ( ! layer->vtable) {
    int rv =  msInitializeVirtualTable(layer);
    if (rv != MS_SUCCESS)
      return rv;
  }

  return layer->vtable->LayerResultsGetShape(layer, shape, tile, record);
} */

/*
** Used to retrieve a shape by index. All data sources must be capable of random access using
** a record number(s) of some sort.
*/
int msLayerGetShape(layerObj *layer, shapeObj *shape, resultObj *record)
{
  int rv;
  
  if( ! layer->vtable) {
    rv =  msInitializeVirtualTable(layer);
    if(rv != MS_SUCCESS)
      return rv;
  }

  /*
  ** TODO: This is where dynamic joins could happen. Joined attributes would be
  ** tagged on to the main attributes with the naming scheme [join name].[item name].
  */

  rv = layer->vtable->LayerGetShape(layer, shape, record);
  if(rv != MS_SUCCESS)
    return rv;
  
  /* RFC89 Apply Layer GeomTransform */
  if(layer->_geomtransform.type != MS_GEOMTRANSFORM_NONE && rv == MS_SUCCESS) {
    rv = msGeomTransformShape(layer->map, layer, shape); 
    if(rv != MS_SUCCESS)
      return rv;
  }

  if(layer->encoding) {
    rv = msLayerEncodeShapeAttributes(layer,shape);
    if(rv != MS_SUCCESS)
      return rv;
  }

  return rv;
}

/*
** Returns the number of shapes that match the potential filter and extent.
 * rectProjection is the projection in which rect is expressed, or can be NULL if
 * rect should be considered in the layer projection.
 * This should be equivalent to calling msLayerWhichShapes() and counting the
 * number of shapes returned by msLayerNextShape(), honouring layer->maxfeatures
 * limitation if layer->maxfeatures>=0, and honouring layer->startindex if
 * layer->startindex >= 1 and paging is enabled.
 * Returns -1 in case of failure.
 */
int msLayerGetShapeCount(layerObj *layer, rectObj rect, projectionObj *rectProjection)
{
  int rv;

  if( ! layer->vtable) {
    rv = msInitializeVirtualTable(layer);
    if(rv != MS_SUCCESS)
      return -1;
  }

  return layer->vtable->LayerGetShapeCount(layer, rect, rectProjection);
}


/*
** Closes resources used by a particular layer.
*/
void msLayerClose(layerObj *layer)
{
  /* no need for items once the layer is closed */
  msLayerFreeItemInfo(layer);
  if(layer->items) {
    msFreeCharArray(layer->items, layer->numitems);
    layer->items = NULL;
    layer->numitems = 0;
  }

  /* clear out items used as part of expressions (bug #2702) -- what about the layer filter? */
  msLayerFreeExpressions(layer);

  if (layer->vtable) {
    layer->vtable->LayerClose(layer);
  }
  msLayerRestoreFromScaletokens(layer);
}

/*
** Clear out items used as part of expressions.
*/
void msLayerFreeExpressions(layerObj *layer)
{
  int i,j,k;

  msFreeExpressionTokens(&(layer->filter));
  msFreeExpressionTokens(&(layer->cluster.group));
  msFreeExpressionTokens(&(layer->cluster.filter));
  for(i=0; i<layer->numclasses; i++) {
    msFreeExpressionTokens(&(layer->class[i]->expression));
    msFreeExpressionTokens(&(layer->class[i]->text));
    for(j=0; j<layer->class[i]->numstyles; j++)
      msFreeExpressionTokens(&(layer->class[i]->styles[j]->_geomtransform));
    for(k=0; k<layer->class[i]->numlabels; k++) {
      msFreeExpressionTokens(&(layer->class[i]->labels[k]->expression));
      msFreeExpressionTokens(&(layer->class[i]->labels[k]->text));
    }
  }
}

/*
** Retrieves a list of attributes available for this layer. Most sources also set the iteminfo array
** at this point. This function is used when processing query results to expose attributes to query
** templates. At that point all attributes are fair game.
*/
int msLayerGetItems(layerObj *layer)
{
  const char *itemNames;
  /* clean up any previously allocated instances */
  msLayerFreeItemInfo(layer);
  if(layer->items) {
    msFreeCharArray(layer->items, layer->numitems);
    layer->items = NULL;
    layer->numitems = 0;
  }

  if ( ! layer->vtable) {
    int rv =  msInitializeVirtualTable(layer);
    if (rv != MS_SUCCESS)
      return rv;
  }

  /* At the end of switch case (default -> break; -> return MS_FAILURE),
   * was following TODO ITEM:
   */
  /* TO DO! Need to add any joined itemd on to the core layer items, one long list!  */
  itemNames = msLayerGetProcessingKey( layer, "ITEMS" );
  if (itemNames) {
    layer->items = msStringSplit(itemNames, ',', &layer->numitems);
    /* populate the iteminfo array */
    return (msLayerInitItemInfo(layer));
  } else
    return layer->vtable->LayerGetItems(layer);
}

/*
** Returns extent of spatial coverage for a layer.
**
** If layer->extent is set then this value is used, otherwise the
** driver-specific implementation is called (this can be expensive).
**
** If layer is not already opened then it is opened and closed (so this
** function can be called on both opened or closed layers).
**
** Returns MS_SUCCESS/MS_FAILURE.
*/
int msLayerGetExtent(layerObj *layer, rectObj *extent)
{
  int need_to_close = MS_FALSE, status = MS_SUCCESS;

  if (MS_VALID_EXTENT(layer->extent)) {
    *extent = layer->extent;
    return MS_SUCCESS;
  }

  if (!msLayerIsOpen(layer)) {
    if (msLayerOpen(layer) != MS_SUCCESS)
      return MS_FAILURE;
    need_to_close = MS_TRUE;
  }

  if ( ! layer->vtable) {
    int rv =  msInitializeVirtualTable(layer);
    if (rv != MS_SUCCESS) {
      if (need_to_close)
        msLayerClose(layer);
      return rv;
    }
  }
  status = layer->vtable->LayerGetExtent(layer, extent);

  if (need_to_close)
    msLayerClose(layer);

  return(status);
}

int msLayerGetItemIndex(layerObj *layer, char *item)
{
  int i;

  for(i=0; i<layer->numitems; i++) {
    if(strcasecmp(layer->items[i], item) == 0) return(i);
  }

  return -1; /* item not found */
}

static int string2list(char **list, int *listsize, char *string)
{
  int i;

  for(i=0; i<(*listsize); i++) {
    if(strcasecmp(list[i], string) == 0) {
      /* printf("string2list (duplicate): %s %d\n", string, i); */
      return(i);
    }
  }

  list[i] = msStrdup(string);
  (*listsize)++;

  /* printf("string2list: %s %d\n", string, i); */

  return(i);
}

extern int msyylex(void);
extern int msyylex_destroy(void);

extern int msyystate;
extern char *msyystring; /* string to tokenize */

extern double msyynumber; /* token containers */
extern char *msyystring_buffer;

const char *msExpressionTokenToString(int token) {
  switch(token) {
    case '(': return "(";          
    case ')': return ")";
    case ',': return ",";
    case '+': return "+";
    case '-': return "-";
    case '/': return "/";
    case '*': return "*";
    case '%': return "%";

    case MS_TOKEN_LOGICAL_AND: return " and ";
    case MS_TOKEN_LOGICAL_OR: return " or ";
    case MS_TOKEN_LOGICAL_NOT: return " not ";

    case MS_TOKEN_COMPARISON_EQ: return " = ";
    case MS_TOKEN_COMPARISON_NE: return " != ";
    case MS_TOKEN_COMPARISON_GT: return " > ";
    case MS_TOKEN_COMPARISON_GE: return " >= ";
    case MS_TOKEN_COMPARISON_LT: return " < ";
    case MS_TOKEN_COMPARISON_LE: return " <= ";
    case MS_TOKEN_COMPARISON_IEQ: return "";
    case MS_TOKEN_COMPARISON_RE: return " ~ ";
    case MS_TOKEN_COMPARISON_IRE: return " ~* ";
    case MS_TOKEN_COMPARISON_IN: return " in ";
    case MS_TOKEN_COMPARISON_LIKE: return " like ";

    case MS_TOKEN_COMPARISON_INTERSECTS: return "intersects";
    case MS_TOKEN_COMPARISON_DISJOINT: return "disjoint";
    case MS_TOKEN_COMPARISON_TOUCHES: return "touches";
    case MS_TOKEN_COMPARISON_OVERLAPS: return "overlaps";
    case MS_TOKEN_COMPARISON_CROSSES: return "crosses";
    case MS_TOKEN_COMPARISON_WITHIN: return "within";
    case MS_TOKEN_COMPARISON_CONTAINS: return "contains";
    case MS_TOKEN_COMPARISON_EQUALS: return "equals";
    case MS_TOKEN_COMPARISON_BEYOND: return "beyond";
    case MS_TOKEN_COMPARISON_DWITHIN: return "dwithin";

    case MS_TOKEN_FUNCTION_LENGTH: return "length";
    case MS_TOKEN_FUNCTION_TOSTRING: return "tostring";
    case MS_TOKEN_FUNCTION_COMMIFY: return "commify";
    case MS_TOKEN_FUNCTION_AREA: return "area";
    case MS_TOKEN_FUNCTION_ROUND: return "round";
    case MS_TOKEN_FUNCTION_BUFFER: return "buffer";
    case MS_TOKEN_FUNCTION_DIFFERENCE: return "difference";
    case MS_TOKEN_FUNCTION_SIMPLIFY: return "simplify";
    // case MS_TOKEN_FUNCTION_SIMPLIFYPT:
    case MS_TOKEN_FUNCTION_GENERALIZE: return "generalize";
    default: return NULL;
  }
}

int msTokenizeExpression(expressionObj *expression, char **list, int *listsize)
{
  tokenListNodeObjPtr node;
  int token;

  /* TODO: make sure the constants can't somehow reference invalid expression types */
  /* if(expression->type != MS_EXPRESSION && expression->type != MS_GEOMTRANSFORM_EXPRESSION) return MS_SUCCESS; */

  msAcquireLock(TLOCK_PARSER);
  msyystate = MS_TOKENIZE_EXPRESSION;
  msyystring = expression->string; /* the thing we're tokenizing */

  while((token = msyylex()) != 0) { /* keep processing tokens until the end of the string (\0) */

    if((node = (tokenListNodeObjPtr) malloc(sizeof(tokenListNodeObj))) == NULL) {
      msSetError(MS_MEMERR, NULL, "msTokenizeExpression()");
      goto parse_error;
    }

    node->tokensrc = NULL;

    node->tailifhead = NULL;
    node->next = NULL;

    switch(token) {
      case MS_TOKEN_LITERAL_BOOLEAN:
      case MS_TOKEN_LITERAL_NUMBER:
        node->token = token;
        node->tokenval.dblval = msyynumber;
        break;
      case MS_TOKEN_LITERAL_STRING:
        node->token = token;
        node->tokenval.strval = msStrdup(msyystring_buffer);
        break;
      case MS_TOKEN_LITERAL_TIME:
        node->tokensrc = msStrdup(msyystring_buffer);
        node->token = token;
        msTimeInit(&(node->tokenval.tmval));
        if(msParseTime(msyystring_buffer, &(node->tokenval.tmval)) != MS_TRUE) {
          msSetError(MS_PARSEERR, "Parsing time value failed.", "msTokenizeExpression()");
          free(node);
          goto parse_error;
        }
        break;
      case MS_TOKEN_BINDING_DOUBLE: /* we've encountered an attribute (binding) reference */
      case MS_TOKEN_BINDING_INTEGER:
      case MS_TOKEN_BINDING_STRING:
      case MS_TOKEN_BINDING_TIME:
        node->token = token; /* binding type */
        node->tokenval.bindval.item = msStrdup(msyystring_buffer);
        if(list) node->tokenval.bindval.index = string2list(list, listsize, msyystring_buffer);
        break;
      case MS_TOKEN_BINDING_SHAPE:
        node->token = token;
        break;
      case MS_TOKEN_BINDING_MAP_CELLSIZE:
        node->token = token;
        break;
      case MS_TOKEN_BINDING_DATA_CELLSIZE:
        node->token = token;
        break;        
      case MS_TOKEN_FUNCTION_FROMTEXT: /* we want to process a shape from WKT once and not for every feature being evaluated */
        if((token = msyylex()) != 40) { /* ( */
          msSetError(MS_PARSEERR, "Parsing fromText function failed.", "msTokenizeExpression()");
          free(node);
          goto parse_error;
        }

        if((token = msyylex()) != MS_TOKEN_LITERAL_STRING) {
          msSetError(MS_PARSEERR, "Parsing fromText function failed.", "msTokenizeExpression()");
          free(node);
          goto parse_error;
        }

        node->token = MS_TOKEN_LITERAL_SHAPE;
        node->tokenval.shpval = msShapeFromWKT(msyystring_buffer);

        if(!node->tokenval.shpval) {
          msSetError(MS_PARSEERR, "Parsing fromText function failed, WKT processing failed.", "msTokenizeExpression()");
          free(node);
          goto parse_error;
        }

        /* todo: perhaps process optional args (e.g. projection) */

        if((token = msyylex()) != 41) { /* ) */
          msSetError(MS_PARSEERR, "Parsing fromText function failed.", "msTokenizeExpression()");
          msFreeShape(node->tokenval.shpval);
          free(node->tokenval.shpval);
          free(node);
          goto parse_error;
        }
        break;
      default:
        node->token = token; /* for everything else */
        break;
    }

    /* add node to token list */
    if(expression->tokens == NULL) {
      expression->tokens = node;
    } else {
      if(expression->tokens->tailifhead != NULL) /* this should never be NULL, but just in case */
        expression->tokens->tailifhead->next = node; /* put the node at the end of the list */
    }

    /* repoint the head of the list to the end  - our new element
       this causes a loop if we are at the head, be careful not to
       walk in a loop */
    expression->tokens->tailifhead = node;
  }

  expression->curtoken = expression->tokens; /* point at the first token */

  msReleaseLock(TLOCK_PARSER);
  return MS_SUCCESS;

parse_error:
  msReleaseLock(TLOCK_PARSER);
  return MS_FAILURE;
}


static void buildLayerItemList(layerObj *layer)
{
  int i, j, k, l;
  /*
  ** build layer item list, compute item indexes for explicity item references (e.g. classitem) or item bindings
  */

  /* layer items */
  if(layer->classitem) layer->classitemindex = string2list(layer->items, &(layer->numitems), layer->classitem);
  if(layer->filteritem) layer->filteritemindex = string2list(layer->items, &(layer->numitems), layer->filteritem);
  if(layer->styleitem && (strcasecmp(layer->styleitem, "AUTO") != 0) && (strncasecmp(layer->styleitem, "javascript://",13) != 0)) 
    layer->styleitemindex = string2list(layer->items, &(layer->numitems), layer->styleitem);
  if(layer->labelitem) layer->labelitemindex = string2list(layer->items, &(layer->numitems), layer->labelitem);
  if(layer->utfitem) layer->utfitemindex = string2list(layer->items, &(layer->numitems), layer->utfitem);

  /* layer classes */
  for(i=0; i<layer->numclasses; i++) {
    
    if(layer->class[i]->expression.type == MS_EXPRESSION) /* class expression */
      msTokenizeExpression(&(layer->class[i]->expression), layer->items, &(layer->numitems));

    /* class styles (items, bindings, geomtransform) */
    for(j=0; j<layer->class[i]->numstyles; j++) {
      if(layer->class[i]->styles[j]->rangeitem) 
        layer->class[i]->styles[j]->rangeitemindex = string2list(layer->items, &(layer->numitems), layer->class[i]->styles[j]->rangeitem);
      for(k=0; k<MS_STYLE_BINDING_LENGTH; k++) {
        if(layer->class[i]->styles[j]->bindings[k].item) 
          layer->class[i]->styles[j]->bindings[k].index = string2list(layer->items, &(layer->numitems), layer->class[i]->styles[j]->bindings[k].item);
        if (layer->class[i]->styles[j]->exprBindings[k].type == MS_EXPRESSION)
        {
          msTokenizeExpression(
              &(layer->class[i]->styles[j]->exprBindings[k]),
              layer->items, &(layer->numitems));
        }
      }
      if(layer->class[i]->styles[j]->_geomtransform.type == MS_GEOMTRANSFORM_EXPRESSION)
        msTokenizeExpression(&(layer->class[i]->styles[j]->_geomtransform), layer->items, &(layer->numitems));
    }

    /* class labels and label styles (items, bindings, geomtransform) */
    for(l=0; l<layer->class[i]->numlabels; l++) {
      for(j=0; j<layer->class[i]->labels[l]->numstyles; j++) {
        if(layer->class[i]->labels[l]->styles[j]->rangeitem) 
          layer->class[i]->labels[l]->styles[j]->rangeitemindex = string2list(layer->items, &(layer->numitems), layer->class[i]->labels[l]->styles[j]->rangeitem);
        for(k=0; k<MS_STYLE_BINDING_LENGTH; k++) {
          if(layer->class[i]->labels[l]->styles[j]->bindings[k].item) 
            layer->class[i]->labels[l]->styles[j]->bindings[k].index = string2list(layer->items, &(layer->numitems), layer->class[i]->labels[l]->styles[j]->bindings[k].item);
          if(layer->class[i]->labels[l]->styles[j]->_geomtransform.type == MS_GEOMTRANSFORM_EXPRESSION)
            msTokenizeExpression(&(layer->class[i]->labels[l]->styles[j]->_geomtransform), layer->items, &(layer->numitems));
        }
      }
      for(k=0; k<MS_LABEL_BINDING_LENGTH; k++) {
        if(layer->class[i]->labels[l]->bindings[k].item) 
          layer->class[i]->labels[l]->bindings[k].index = string2list(layer->items, &(layer->numitems), layer->class[i]->labels[l]->bindings[k].item);
        if (layer->class[i]->labels[l]->exprBindings[k].type == MS_EXPRESSION)
        {
          msTokenizeExpression(
              &(layer->class[i]->labels[l]->exprBindings[k]),
              layer->items, &(layer->numitems));
        }
      }

       /* label expression */
      if(layer->class[i]->labels[l]->expression.type == MS_EXPRESSION) msTokenizeExpression(&(layer->class[i]->labels[l]->expression), layer->items, &(layer->numitems));

      /* label text */
      if(layer->class[i]->labels[l]->text.type == MS_EXPRESSION || (layer->class[i]->labels[l]->text.string && strchr(layer->class[i]->labels[l]->text.string,'[') != NULL && strchr(layer->class[i]->labels[l]->text.string,']') != NULL))
        msTokenizeExpression(&(layer->class[i]->labels[l]->text), layer->items, &(layer->numitems));
    }

    /* class text */
    if(layer->class[i]->text.type == MS_EXPRESSION || (layer->class[i]->text.string && strchr(layer->class[i]->text.string,'[') != NULL && strchr(layer->class[i]->text.string,']') != NULL))
      msTokenizeExpression(&(layer->class[i]->text), layer->items, &(layer->numitems));
  }

  /* layer filter */
  if(layer->filter.type == MS_EXPRESSION) msTokenizeExpression(&(layer->filter), layer->items, &(layer->numitems));

  /* cluster expressions */
  if(layer->cluster.group.type == MS_EXPRESSION) msTokenizeExpression(&(layer->cluster.group), layer->items, &(layer->numitems));
  if(layer->cluster.filter.type == MS_EXPRESSION) msTokenizeExpression(&(layer->cluster.filter), layer->items, &(layer->numitems));

  /* utfdata */
  if(layer->utfdata.type == MS_EXPRESSION || (layer->utfdata.string && strchr(layer->utfdata.string,'[') != NULL && strchr(layer->utfdata.string,']') != NULL)) {
    msTokenizeExpression(&(layer->utfdata), layer->items, &(layer->numitems));
  }
}

/*
** This function builds a list of items necessary to draw or query a particular layer by
** examining the contents of the various xxxxitem parameters and expressions. That list is
** then used to set the iteminfo variable.
*/
int msLayerWhichItems(layerObj *layer, int get_all, const char *metadata)
{
  int i, j, k, l, rv;
  int nt=0;

  if (!layer->vtable) {
    rv =  msInitializeVirtualTable(layer);
    if (rv != MS_SUCCESS) return rv;
  }

  /* Cleanup any previous item selection */
  msLayerFreeItemInfo(layer);
  if(layer->items) {
    msFreeCharArray(layer->items, layer->numitems);
    layer->items = NULL;
    layer->numitems = 0;
  }

  /*
  ** need a count of potential items/attributes needed
  */

  /* layer level counts */
  layer->classitemindex = -1;
  layer->filteritemindex = -1;
  layer->styleitemindex = -1;
  layer->labelitemindex = -1;
  layer->utfitemindex = -1;

  if(layer->classitem) nt++;
  if(layer->filteritem) nt++;
  if(layer->styleitem &&
     (strcasecmp(layer->styleitem, "AUTO") != 0) &&
     (strncasecmp(layer->styleitem, "javascript://", 13) != 0)) nt++;
     
  if(layer->filter.type == MS_EXPRESSION)
    nt += msCountChars(layer->filter.string, '[');

  if(layer->cluster.group.type == MS_EXPRESSION)
    nt += msCountChars(layer->cluster.group.string, '[');

  if(layer->cluster.filter.type == MS_EXPRESSION)
    nt += msCountChars(layer->cluster.filter.string, '[');

  if(layer->labelitem) nt++;
  if(layer->utfitem) nt++;

  if(layer->_geomtransform.type == MS_GEOMTRANSFORM_EXPRESSION)
    msTokenizeExpression(&layer->_geomtransform, layer->items, &(layer->numitems));

  /* class level counts */
  for(i=0; i<layer->numclasses; i++) {

    for(j=0; j<layer->class[i]->numstyles; j++) {
      if(layer->class[i]->styles[j]->rangeitem) nt++;
      nt += layer->class[i]->styles[j]->numbindings;
      if(layer->class[i]->styles[j]->_geomtransform.type == MS_GEOMTRANSFORM_EXPRESSION)
        nt += msCountChars(layer->class[i]->styles[j]->_geomtransform.string, '[');
      for(k=0; k<MS_STYLE_BINDING_LENGTH; k++) {
        if (layer->class[i]->styles[j]->exprBindings[k].type == MS_EXPRESSION)
        {
          nt += msCountChars(layer->class[i]->styles[j]->exprBindings[k].string, '[');
        }
      }
    }

    if(layer->class[i]->expression.type == MS_EXPRESSION)
      nt += msCountChars(layer->class[i]->expression.string, '[');

    for(l=0; l<layer->class[i]->numlabels; l++) {
      nt += layer->class[i]->labels[l]->numbindings;
      for(j=0; j<layer->class[i]->labels[l]->numstyles; j++) {
        if(layer->class[i]->labels[l]->styles[j]->rangeitem) nt++;
        nt += layer->class[i]->labels[l]->styles[j]->numbindings;
        if(layer->class[i]->labels[l]->styles[j]->_geomtransform.type == MS_GEOMTRANSFORM_EXPRESSION)
          nt += msCountChars(layer->class[i]->labels[l]->styles[j]->_geomtransform.string, '[');
      }
      for(k=0; k<MS_LABEL_BINDING_LENGTH; k++) {
        if (layer->class[i]->labels[l]->exprBindings[k].type == MS_EXPRESSION)
        {
          nt += msCountChars(layer->class[i]->labels[l]->exprBindings[k].string, '[');
        }
      }

      if(layer->class[i]->labels[l]->expression.type == MS_EXPRESSION)
        nt += msCountChars(layer->class[i]->labels[l]->expression.string, '[');
      if(layer->class[i]->labels[l]->text.type == MS_EXPRESSION || (layer->class[i]->labels[l]->text.string && strchr(layer->class[i]->labels[l]->text.string,'[') != NULL && strchr(layer->class[i]->labels[l]->text.string,']') != NULL))
        nt += msCountChars(layer->class[i]->labels[l]->text.string, '[');
    }

    if(layer->class[i]->text.type == MS_EXPRESSION || (layer->class[i]->text.string && strchr(layer->class[i]->text.string,'[') != NULL && strchr(layer->class[i]->text.string,']') != NULL))
      nt += msCountChars(layer->class[i]->text.string, '[');
  }

  /* utfgrid count */
  if(layer->utfdata.type == MS_EXPRESSION || (layer->utfdata.string && strchr(layer->utfdata.string,'[') != NULL && strchr(layer->utfdata.string,']') != NULL))
    nt += msCountChars(layer->utfdata.string, '[');

  /*
  ** allocate space for the item list (worse case size)
  */

  /* always retrieve all items in some cases */
  if(layer->connectiontype == MS_INLINE ||
      (layer->map->outputformat && layer->map->outputformat->renderer == MS_RENDER_WITH_KML)) {
    get_all = MS_TRUE;
  }
  if( get_all ) {
    rv = msLayerGetItems(layer);
    if(nt > 0) /* need to realloc the array to accept the possible new items*/
      layer->items = (char **)msSmallRealloc(layer->items, sizeof(char *)*(layer->numitems + nt));
  } else {
    rv = layer->vtable->LayerCreateItems(layer, nt);
  }
  if(rv != MS_SUCCESS)
    return rv;

  buildLayerItemList(layer);

  if(metadata) {
    char **tokens;
    int n = 0;
    int j;
    int bFound = 0;

    tokens = msStringSplit(metadata, ',', &n);
    if(tokens) {
      for(i=0; i<n; i++) {
        bFound = 0;
        for(j=0; j<layer->numitems; j++) {
          if(strcasecmp(tokens[i], layer->items[j]) == 0) {
            bFound = 1;
            break;
          }
        }

        if(!bFound) {
          layer->numitems++;
          layer->items =  (char **)msSmallRealloc(layer->items, sizeof(char *)*(layer->numitems));
          layer->items[layer->numitems-1] = msStrdup(tokens[i]);
        }
      }
      msFreeCharArray(tokens, n);
    }

    /* If we didn't retrieve all items of the layer, then do it, so that the */
    /* order of the layer->items array is consistent with it. This is */
    /* important so that WFS DescribeFeatureType and GetFeature requests */
    /* return items in the same order */
    if( !get_all && layer->numitems ) {
        char** unsorted_items = layer->items;
        int numitems = layer->numitems;

        /* Retrieve all items */
        layer->items = NULL;
        layer->numitems = 0;
        rv = msLayerGetItems(layer);
        if( rv != MS_SUCCESS ) {
            msFreeCharArray(unsorted_items, numitems);
            return rv;
        }

        /* Sort unsorted_items in the order of layer->items */
        char** sorted_items = (char **)msSmallMalloc(sizeof(char*) * numitems);
        int num_sorted_items = 0;
        for( i = 0; i < layer->numitems; i++ )
        {
            if( layer->items[i] )
            {
                for( j = 0; j < numitems; j++ )
                {
                    if( unsorted_items[j] &&
                        strcasecmp(layer->items[i], unsorted_items[j]) == 0 )
                    {
                        sorted_items[num_sorted_items] = layer->items[i];
                        num_sorted_items ++;

                        layer->items[i] = NULL;
                        msFree(unsorted_items[j]);
                        unsorted_items[j] = NULL;
                        break;
                    }
                }
            }
        }

        /* Add items that are not returned by msLayerGetItems() (not sure if that can happen) */
        for( j = 0; j < numitems; j++ )
        {
            if( unsorted_items[j] )
            {
                sorted_items[num_sorted_items] = unsorted_items[j];
                num_sorted_items ++;
            }
        }

        if(layer->items) {
            msFreeCharArray(layer->items, layer->numitems);
        }
        msFreeCharArray(unsorted_items, numitems);

        layer->items = sorted_items;
        layer->numitems = numitems;

        /* Re-run buildLayerItemList() with the now correctly sorted items */
        buildLayerItemList(layer);
    }

  }

  /* populate the iteminfo array */
  if(layer->numitems == 0)
    return(MS_SUCCESS);

  return(msLayerInitItemInfo(layer));
}

/*
** A helper function to set the items to be retrieved with a particular shape. Unused at the moment but will be used
** from within MapScript. Should not need modification.
*/
int msLayerSetItems(layerObj *layer, char **items, int numitems)
{
  int i;
  /* Cleanup any previous item selection */
  msLayerFreeItemInfo(layer);
  if(layer->items) {
    msFreeCharArray(layer->items, layer->numitems);
    layer->items = NULL;
    layer->numitems = 0;
  }

  /* now allocate and set the layer item parameters  */
  layer->items = (char **)malloc(sizeof(char *)*numitems);
  MS_CHECK_ALLOC(layer->items, sizeof(char *)*numitems, MS_FAILURE);

  for(i=0; i<numitems; i++)
    layer->items[i] = msStrdup(items[i]);
  layer->numitems = numitems;

  /* populate the iteminfo array */
  return(msLayerInitItemInfo(layer));

  return(MS_SUCCESS);
}

/*
** Fills a classObj with style info from the specified shape.  This is used
** with STYLEITEM AUTO when rendering shapes.
** For optimal results, this should be called immediately after
** GetNextShape() or GetShape() so that the shape doesn't have to be read
** twice.
**
*/
int msLayerGetAutoStyle(mapObj *map, layerObj *layer, classObj *c, shapeObj* shape)
{
  if ( ! layer->vtable) {
    int rv =  msInitializeVirtualTable(layer);
    if (rv != MS_SUCCESS)
      return rv;
  }
  return layer->vtable->LayerGetAutoStyle(map, layer, c, shape);
}

/*
** Fills a classObj with style info from the specified attribute.  This is used
** with STYLEITEM "attribute" when rendering shapes.
**
*/
int msLayerGetFeatureStyle(mapObj *map, layerObj *layer, classObj *c, shapeObj* shape)
{
  char* stylestring = NULL;
  if (layer->styleitem && layer->styleitemindex >=0) {
    stylestring = msStrdup(shape->values[layer->styleitemindex]);
  }
  else if (strncasecmp(layer->styleitem,"javascript://",13) == 0) {
#ifdef USE_V8_MAPSCRIPT
    char *filename = layer->styleitem+13;

    if (!map->v8context) {
      msV8CreateContext(map);
      if (!map->v8context)
      {
        msSetError(MS_V8ERR, "Unable to create v8 context.", "msLayerGetFeatureStyle()");
        return MS_FAILURE;
      }
    }

    if (*filename == '\0') {
      msSetError(MS_V8ERR, "Invalid javascript filename: \"%s\".", "msLayerGetFeatureStyle()", layer->styleitem);
      return MS_FAILURE;
    }
    
    stylestring = msV8GetFeatureStyle(map, filename, layer, shape);
#else
      msSetError(MS_V8ERR, "V8 Javascript support is not available.", "msLayerGetFeatureStyle()");
      return MS_FAILURE;
#endif
  }
  else { /* unknown styleitem */
    return MS_FAILURE;
  }

  /* try to find out the current style format */
  if (!stylestring)
    return MS_FAILURE;

  if (strncasecmp(stylestring,"style",5) == 0) {
    resetClassStyle(c);
    c->layer = layer;
    if (msMaybeAllocateClassStyle(c, 0)) {
      free(stylestring);
      return(MS_FAILURE);
    }

    msUpdateStyleFromString(c->styles[0], stylestring, MS_FALSE);
    if(c->styles[0]->symbolname) {
      if((c->styles[0]->symbol =  msGetSymbolIndex(&(map->symbolset), c->styles[0]->symbolname, MS_TRUE)) == -1) {
        msSetError(MS_MISCERR, "Undefined symbol \"%s\" in class of layer %s.", "msLayerGetFeatureStyle()", 
                   c->styles[0]->symbolname, layer->name);
        free(stylestring);
        return MS_FAILURE;
      }
    }
  } else if (strncasecmp(stylestring,"class",5) == 0) {
    if (strcasestr(stylestring, " style ") != NULL) {
      /* reset style if stylestring contains style definitions */
      resetClassStyle(c);
      c->layer = layer;
    }
    msUpdateClassFromString(c, stylestring, MS_FALSE);
  } else if (strncasecmp(stylestring,"pen",3) == 0 || strncasecmp(stylestring,"brush",5) == 0 ||
             strncasecmp(stylestring,"symbol",6) == 0 || strncasecmp(stylestring,"label",5) == 0) {
    msOGRUpdateStyleFromString(map, layer, c, stylestring);
  } else {
    resetClassStyle(c);
  }

  free(stylestring);
  return MS_SUCCESS;
}


/*
Returns the number of inline feature of a layer
*/
int msLayerGetNumFeatures(layerObj *layer)
{
    int need_to_close = MS_FALSE, result = -1;

    if (!msLayerIsOpen(layer)) {
        if (msLayerOpen(layer) != MS_SUCCESS)
            return result;
        need_to_close = MS_TRUE;
    }

    if (!layer->vtable) {
        int rv = msInitializeVirtualTable(layer);
        if (rv != MS_SUCCESS)
            return result;
    }

    result = layer->vtable->LayerGetNumFeatures(layer);

    if (need_to_close)
        msLayerClose(layer);

    return(result);
}

void
msLayerSetProcessingKey( layerObj *layer, const char *key, const char *value)

{
  int len = strlen(key);
  int i;
  char *directive = NULL;

  if( value != NULL ) {
    directive = (char *) msSmallMalloc(strlen(key)+strlen(value)+2);
    sprintf( directive, "%s=%s", key, value );
  }

  for( i = 0; i < layer->numprocessing; i++ ) {
    if( strncasecmp( key, layer->processing[i], len ) == 0
        && layer->processing[i][len] == '=' ) {
      free( layer->processing[i] );

      /*
      ** Either replace the existing entry with a new one or
      ** clear the entry.
      */
      if( directive != NULL )
        layer->processing[i] = directive;
      else {
        layer->processing[i] = layer->processing[layer->numprocessing-1];
        layer->processing[layer->numprocessing-1] = NULL;
        layer->numprocessing--;
      }
      return;
    }
  }

  /* otherwise add the directive at the end. */

  if( directive != NULL ) {
    msLayerAddProcessing( layer, directive );
    free( directive );
  }
}

void msLayerSubstituteProcessing( layerObj *layer, const char *from, const char *to ) {
  int i;
  for( i = 0; i < layer->numprocessing; i++ ) {
    layer->processing[i] = msCaseReplaceSubstring(layer->processing[i], from, to);
  }
}

void msLayerAddProcessing( layerObj *layer, const char *directive )

{
  layer->numprocessing++;
  if( layer->numprocessing == 1 )
    layer->processing = (char **) msSmallMalloc(2*sizeof(char *));
  else
    layer->processing = (char **) msSmallRealloc(layer->processing, sizeof(char*) * (layer->numprocessing+1) );
  layer->processing[layer->numprocessing-1] = msStrdup(directive);
  layer->processing[layer->numprocessing] = NULL;
}

char *msLayerGetProcessing( layerObj *layer, int proc_index)
{
  if (proc_index < 0 || proc_index >= layer->numprocessing) {
    msSetError(MS_CHILDERR, "Invalid processing index.", "msLayerGetProcessing()");
    return NULL;
  } else {
    return layer->processing[proc_index];
  }
}

char *msLayerGetProcessingKey( layerObj *layer, const char *key )
{
  int i, len = strlen(key);

  for( i = 0; i < layer->numprocessing; i++ ) {
    if( strncasecmp(layer->processing[i],key,len) == 0
        && layer->processing[i][len] == '=' )
      return layer->processing[i] + len + 1;
  }

  return NULL;
}


/************************************************************************/
/*                       msLayerGetMaxFeaturesToDraw                    */
/*                                                                      */
/*      Check to see if maxfeaturestodraw is set as a metadata or an    */
/*      output format option. Used for vector layers to limit the       */
/*      number of fatures rendered.                                     */
/************************************************************************/
int msLayerGetMaxFeaturesToDraw(layerObj *layer, outputFormatObj *format)
{
  int nMaxFeatures = -1;
  const char *pszTmp = NULL;
  if (layer) {
    nMaxFeatures = layer->maxfeatures;
    pszTmp = msLookupHashTable(&layer->metadata, "maxfeaturestodraw");
    if (pszTmp)
      nMaxFeatures = atoi(pszTmp);
    else {
      pszTmp = msLookupHashTable(&layer->map->web.metadata, "maxfeaturestodraw");
      if (pszTmp)
        nMaxFeatures = atoi(pszTmp);
    }
  }
  if(format) {
    if (nMaxFeatures < 0)
      nMaxFeatures = atoi(msGetOutputFormatOption( format, "maxfeaturestodraw", "-1"));
  }

  return nMaxFeatures;

}
int msLayerClearProcessing( layerObj *layer )
{
  if (layer->numprocessing > 0) {
    msFreeCharArray( layer->processing, layer->numprocessing );
    layer->processing = NULL;
    layer->numprocessing = 0;
  }
  return layer->numprocessing;
}


int
makeTimeFilter(layerObj *lp,
               const char *timestring,
               const char *timefield,
               const int addtimebacktics)
{

  char **atimes, **tokens = NULL;
  int numtimes,i, ntmp = 0;
  char *pszBuffer = NULL;
  int bOnlyExistingFilter = 0;

  if (!lp || !timestring || !timefield)
    return MS_FALSE;

  /* parse the time string. We support dicrete times (eg 2004-09-21),  */
  /* multiple times (2004-09-21, 2004-09-22, ...) */
  /* and range(s) (2004-09-21/2004-09-25, 2004-09-27/2004-09-29) */

  if (strstr(timestring, ",") == NULL &&
      strstr(timestring, "/") == NULL) { /* discrete time */
    /*
    if(lp->filteritem) free(lp->filteritem);
    lp->filteritem = msStrdup(timefield);
    if (&lp->filter)
      msFreeExpression(&lp->filter);
    */

    /* if the filter is set and it's a sting type, concatenate it with
       the time. If not just free it */
     if (lp->filter.string && lp->filter.type == MS_STRING) {
      pszBuffer = msStringConcatenate(pszBuffer, "((");
      pszBuffer = msStringConcatenate(pszBuffer, lp->filter.string);
      pszBuffer = msStringConcatenate(pszBuffer, ") and ");
    } else {
      msFreeExpression(&lp->filter);
    }

    pszBuffer = msStringConcatenate(pszBuffer, "(");
    if (addtimebacktics)
      pszBuffer = msStringConcatenate(pszBuffer,  "`");

    if (addtimebacktics)
      pszBuffer = msStringConcatenate(pszBuffer, "[");
    pszBuffer = msStringConcatenate(pszBuffer, (char *)timefield);
    if (addtimebacktics)
      pszBuffer = msStringConcatenate(pszBuffer, "]");
    if (addtimebacktics)
      pszBuffer = msStringConcatenate(pszBuffer,  "`");


    pszBuffer = msStringConcatenate(pszBuffer, " = ");
    if (addtimebacktics)
      pszBuffer = msStringConcatenate(pszBuffer,  "`");
    else
      pszBuffer = msStringConcatenate(pszBuffer,  "'");

    pszBuffer = msStringConcatenate(pszBuffer, (char *)timestring);
    if (addtimebacktics)
      pszBuffer = msStringConcatenate(pszBuffer,  "`");
    else
      pszBuffer = msStringConcatenate(pszBuffer,  "'");

    pszBuffer = msStringConcatenate(pszBuffer, ")");

    /* if there was a filter, It was concatenate with an And ans should be closed*/
    if(lp->filter.string && lp->filter.type == MS_STRING) {
      pszBuffer = msStringConcatenate(pszBuffer, ")");
    }

    msLoadExpressionString(&lp->filter, pszBuffer);

    if (pszBuffer)
      msFree(pszBuffer);

    return MS_TRUE;
  }

  atimes = msStringSplit(timestring, ',', &numtimes);
  if (atimes == NULL || numtimes < 1) {
    msFreeCharArray(atimes,numtimes);
    return MS_FALSE;
  }

  if (lp->filter.string && lp->filter.type == MS_STRING) {
    pszBuffer = msStringConcatenate(pszBuffer, "((");
    pszBuffer = msStringConcatenate(pszBuffer, lp->filter.string);
    pszBuffer = msStringConcatenate(pszBuffer, ") and ");
    /*this flag is used to indicate that the buffer contains only the
      existing filter. It is set to 0 when time filter parts are
      added to the buffer */
    bOnlyExistingFilter = 1;
  } else
    msFreeExpression(&lp->filter);

  /* check to see if we have ranges by parsing the first entry */
  tokens = msStringSplit(atimes[0],  '/', &ntmp);
  if (ntmp == 2) { /* ranges */
    msFreeCharArray(tokens, ntmp);
    for (i=0; i<numtimes; i++) {
      tokens = msStringSplit(atimes[i],  '/', &ntmp);
      if (ntmp == 2) {
        if (pszBuffer && strlen(pszBuffer) > 0 && bOnlyExistingFilter == 0)
          pszBuffer = msStringConcatenate(pszBuffer, " OR ");
        else
          pszBuffer = msStringConcatenate(pszBuffer, "(");

        bOnlyExistingFilter = 0;

        pszBuffer = msStringConcatenate(pszBuffer, "(");
        if (addtimebacktics)
          pszBuffer = msStringConcatenate(pszBuffer,  "`");

        if (addtimebacktics)
          pszBuffer = msStringConcatenate(pszBuffer, "[");
        pszBuffer = msStringConcatenate(pszBuffer, (char *)timefield);
        if (addtimebacktics)
          pszBuffer = msStringConcatenate(pszBuffer, "]");

        if (addtimebacktics)
          pszBuffer = msStringConcatenate(pszBuffer,  "`");

        pszBuffer = msStringConcatenate(pszBuffer, " >= ");
        if (addtimebacktics)
          pszBuffer = msStringConcatenate(pszBuffer,  "`");
        else
          pszBuffer = msStringConcatenate(pszBuffer,  "'");

        pszBuffer = msStringConcatenate(pszBuffer, tokens[0]);
        if (addtimebacktics)
          pszBuffer = msStringConcatenate(pszBuffer,  "`");
        else
          pszBuffer = msStringConcatenate(pszBuffer,  "'");
        pszBuffer = msStringConcatenate(pszBuffer, " AND ");

        if (addtimebacktics)
          pszBuffer = msStringConcatenate(pszBuffer,  "`");

        if (addtimebacktics)
          pszBuffer = msStringConcatenate(pszBuffer, "[");
        pszBuffer = msStringConcatenate(pszBuffer, (char *)timefield);
        if (addtimebacktics)
          pszBuffer = msStringConcatenate(pszBuffer, "]");
        if (addtimebacktics)
          pszBuffer = msStringConcatenate(pszBuffer,  "`");

        pszBuffer = msStringConcatenate(pszBuffer, " <= ");

        if (addtimebacktics)
          pszBuffer = msStringConcatenate(pszBuffer,  "`");
        else
          pszBuffer = msStringConcatenate(pszBuffer,  "'");
        pszBuffer = msStringConcatenate(pszBuffer, tokens[1]);
        if (addtimebacktics)
          pszBuffer = msStringConcatenate(pszBuffer,  "`");
        else
          pszBuffer = msStringConcatenate(pszBuffer,  "'");
        pszBuffer = msStringConcatenate(pszBuffer, ")");
      }

      msFreeCharArray(tokens, ntmp);
    }
    if (pszBuffer && strlen(pszBuffer) > 0 && bOnlyExistingFilter == 0)
      pszBuffer = msStringConcatenate(pszBuffer, ")");
  } else if (ntmp == 1) { /* multiple times */
    msFreeCharArray(tokens, ntmp);
    pszBuffer = msStringConcatenate(pszBuffer, "(");
    for (i=0; i<numtimes; i++) {
      if (i > 0)
        pszBuffer = msStringConcatenate(pszBuffer, " OR ");

      pszBuffer = msStringConcatenate(pszBuffer, "(");
      if (addtimebacktics)
        pszBuffer = msStringConcatenate(pszBuffer, "`");

      if (addtimebacktics)
        pszBuffer = msStringConcatenate(pszBuffer, "[");
      pszBuffer = msStringConcatenate(pszBuffer, (char *)timefield);
      if (addtimebacktics)
        pszBuffer = msStringConcatenate(pszBuffer, "]");

      if (addtimebacktics)
        pszBuffer = msStringConcatenate(pszBuffer, "`");

      pszBuffer = msStringConcatenate(pszBuffer, " = ");

      if (addtimebacktics)
        pszBuffer = msStringConcatenate(pszBuffer, "`");
      else
        pszBuffer = msStringConcatenate(pszBuffer,  "'");
      pszBuffer = msStringConcatenate(pszBuffer, atimes[i]);
      if (addtimebacktics)
        pszBuffer = msStringConcatenate(pszBuffer,  "`");
      else
        pszBuffer = msStringConcatenate(pszBuffer,  "'");
      pszBuffer = msStringConcatenate(pszBuffer, ")");
    }
    pszBuffer = msStringConcatenate(pszBuffer, ")");
  } else {
    msFreeCharArray(tokens, ntmp);
    msFreeCharArray(atimes, numtimes);
    msFree(pszBuffer);
    return MS_FALSE;
  }

  msFreeCharArray(atimes, numtimes);

  /* load the string to the filter */
  if (pszBuffer && strlen(pszBuffer) > 0) {
    if(lp->filter.string && lp->filter.type == MS_STRING)
      pszBuffer = msStringConcatenate(pszBuffer, ")");
    /*
    if(lp->filteritem)
      free(lp->filteritem);
    lp->filteritem = msStrdup(timefield);
    */

    msLoadExpressionString(&lp->filter, pszBuffer);

  }
  msFree(pszBuffer);
  return MS_TRUE;
}

/**
  set the filter parameter for a time filter
**/

int msLayerSetTimeFilter(layerObj *lp, const char *timestring,
                         const char *timefield)
{
  if ( ! lp->vtable) {
    int rv =  msInitializeVirtualTable(lp);
    if (rv != MS_SUCCESS)
      return rv;
  }
  return lp->vtable->LayerSetTimeFilter(lp, timestring, timefield);
}

int
msLayerMakeBackticsTimeFilter(layerObj *lp, const char *timestring,
                              const char *timefield)
{
  return makeTimeFilter(lp, timestring, timefield, MS_TRUE);
}

int
msLayerMakePlainTimeFilter(layerObj *lp, const char *timestring,
                           const char *timefield)
{
  return makeTimeFilter(lp, timestring, timefield, MS_FALSE);
}


/*
 * Dummies / default actions for layers
 */
int LayerDefaultInitItemInfo(layerObj *layer)
{
  return MS_SUCCESS;
}

void LayerDefaultFreeItemInfo(layerObj *layer)
{
  return;
}

int LayerDefaultOpen(layerObj *layer)
{
  return MS_FAILURE;
}

int LayerDefaultIsOpen(layerObj *layer)
{
  return MS_FALSE;
}

int LayerDefaultWhichShapes(layerObj *layer, rectObj rect, int isQuery)
{
  return MS_SUCCESS;
}

int LayerDefaultNextShape(layerObj *layer, shapeObj *shape)
{
  return MS_FAILURE;
}

int LayerDefaultGetShape(layerObj *layer, shapeObj *shape, resultObj *record)
{
  return MS_FAILURE;
}

int LayerDefaultGetShapeCount(layerObj *layer, rectObj rect, projectionObj *rectProjection)
{
  int status;
  shapeObj shape, searchshape;
  int nShapeCount = 0;
  rectObj searchrect = rect;
  reprojectionObj* reprojector = NULL;

  msInitShape(&searchshape);
  msRectToPolygon(searchrect, &searchshape);

  if( rectProjection != NULL ) 
  {
    if(layer->project && msProjectionsDiffer(&(layer->projection), rectProjection))
      msProjectRect(rectProjection, &(layer->projection), &searchrect); /* project the searchrect to source coords */
    else
      layer->project = MS_FALSE;
  }

  status = msLayerWhichShapes(layer, searchrect, MS_TRUE) ;
  if( status == MS_FAILURE )
  {
    msFreeShape(&searchshape);
    return -1;
  }
  else if( status == MS_DONE )
  {
    msFreeShape(&searchshape);
    return 0;
  }

  msInitShape(&shape);
  while((status = msLayerNextShape(layer, &shape)) == MS_SUCCESS)
  {
    if( rectProjection != NULL ) 
    {
      if(layer->project && msProjectionsDiffer(&(layer->projection), rectProjection))
      {
        if( reprojector == NULL )
            reprojector = msProjectCreateReprojector(&(layer->projection), rectProjection);
        if( reprojector )
            msProjectShapeEx(reprojector, &shape);
      }
      else
        layer->project = MS_FALSE;

      if(msRectContained(&shape.bounds, &rect) == MS_TRUE) { /* if the whole shape is in, don't intersect */
        status = MS_TRUE;
      } else {
        switch(shape.type) { /* make sure shape actually intersects the qrect (ADD FUNCTIONS SPECIFIC TO RECTOBJ) */
          case MS_SHAPE_POINT:
            status = msIntersectMultipointPolygon(&shape, &searchshape);
            break;
          case MS_SHAPE_LINE:
            status = msIntersectPolylinePolygon(&shape, &searchshape);
            break;
          case MS_SHAPE_POLYGON:
            status = msIntersectPolygons(&shape, &searchshape);
            break;
          default:
            break;
        }
      }
    }
    else
      status = MS_TRUE;

    if( status == MS_TRUE )
      nShapeCount++ ;
    msFreeShape(&shape);
    if(layer->maxfeatures > 0 && layer->maxfeatures == nShapeCount)
      break;
  }

  msFreeShape(&searchshape);
  msProjectDestroyReprojector(reprojector);

  return nShapeCount;
}

int LayerDefaultClose(layerObj *layer)
{
  return MS_SUCCESS;
}

int LayerDefaultGetItems(layerObj *layer)
{
  return MS_SUCCESS; /* returning no items is legit */
}

int
msLayerApplyCondSQLFilterToLayer(FilterEncodingNode *psNode, mapObj *map,
                                 int iLayerIndex)
{
  return FLTLayerApplyCondSQLFilterToLayer(psNode, map, iLayerIndex);
}

int msLayerSupportsPaging(layerObj *layer)
{
  if (layer &&
      ((layer->connectiontype == MS_ORACLESPATIAL) ||
       (layer->connectiontype == MS_POSTGIS)) )
    return MS_TRUE;

  return MS_FALSE;
}

int msLayerApplyPlainFilterToLayer(FilterEncodingNode *psNode, mapObj *map, int iLayerIndex);

/*
 * msLayerSupportsSorting()
 *
 * Returns MS_TRUE if the layer supports sorting/ordering.
 */
int msLayerSupportsSorting(layerObj *layer)
{
  if (layer && (
    (layer->connectiontype == MS_OGR) || (layer->connectiontype == MS_POSTGIS) || (layer->connectiontype == MS_ORACLESPATIAL) || ((layer->connectiontype == MS_PLUGIN) && (strstr(layer->plugin_library,"msplugin_oracle") != NULL)) || ((layer->connectiontype == MS_PLUGIN) && (strstr(layer->plugin_library,"msplugin_mssql2008") != NULL))
               )
     )
    return MS_TRUE;

  return MS_FALSE;
}

/*
 * msLayerSetSort()
 *
 * Copy the sortBy clause passed as an argument into the layer sortBy member.
 */
void msLayerSetSort(layerObj *layer, const sortByClause* sortBy)
{
  int i;
  for(i=0;i<layer->sortBy.nProperties;i++)
    msFree(layer->sortBy.properties[i].item);
  msFree(layer->sortBy.properties);

  layer->sortBy.nProperties = sortBy->nProperties;
  layer->sortBy.properties = (sortByProperties*) msSmallMalloc(sortBy->nProperties * sizeof(sortByProperties));
  for(i=0;i<layer->sortBy.nProperties;i++) {
    layer->sortBy.properties[i].item = msStrdup(sortBy->properties[i].item);
    layer->sortBy.properties[i].sortOrder = sortBy->properties[i].sortOrder;
  }
 }

/*
 * msLayerBuildSQLOrderBy()
 *
 * Returns the content of a SQL ORDER BY clause from the sortBy member of
 * the layer. The string does not contain the "ORDER BY" keywords itself.
 */
char* msLayerBuildSQLOrderBy(layerObj *layer)
{
  char* strOrderBy = NULL;
  if( layer->sortBy.nProperties > 0 ) {
    int i;
    for(i=0;i<layer->sortBy.nProperties;i++) {
      char* escaped = msLayerEscapePropertyName(layer, layer->sortBy.properties[i].item);
      if( i > 0 )
        strOrderBy = msStringConcatenate(strOrderBy, ", ");
      strOrderBy = msStringConcatenate(strOrderBy, escaped);
      if( layer->sortBy.properties[i].sortOrder == SORT_DESC )
        strOrderBy = msStringConcatenate(strOrderBy, " DESC");
      msFree(escaped);
    }
  }
  return strOrderBy;
}

int
msLayerApplyPlainFilterToLayer(FilterEncodingNode *psNode, mapObj *map, int iLayerIndex)
{
  return FLTLayerApplyPlainFilterToLayer(psNode, map, iLayerIndex);
}

int msLayerGetPaging(layerObj *layer)
{
  if ( ! layer->vtable) {
    int rv =  msInitializeVirtualTable(layer);
    if (rv != MS_SUCCESS) {
      msSetError(MS_MISCERR, "Unable to initialize virtual table", "msLayerGetPaging()");
      return MS_FAILURE;
    }
  }
  return layer->vtable->LayerGetPaging(layer);
}

void msLayerEnablePaging(layerObj *layer, int value)
{
  if ( ! layer->vtable) {
    int rv =  msInitializeVirtualTable(layer);
    if (rv != MS_SUCCESS) {
      msSetError(MS_MISCERR, "Unable to initialize virtual table", "msLayerEnablePaging()");
      return;
    }
  }
  layer->vtable->LayerEnablePaging(layer, value);
}

int LayerDefaultGetExtent(layerObj *layer, rectObj *extent)
{
  return MS_FAILURE;
}

int LayerDefaultGetAutoStyle(mapObj *map, layerObj *layer, classObj *c, shapeObj *shape)
{
  msSetError(MS_MISCERR, "'STYLEITEM AUTO' not supported for this data source.", "msLayerGetAutoStyle()");
  return MS_FAILURE;
}

int LayerDefaultCloseConnection(layerObj *layer)
{
  return MS_SUCCESS;
}

int LayerDefaultCreateItems(layerObj *layer, const int nt)
{
  if (nt > 0) {
    layer->items = (char **)calloc(nt, sizeof(char *)); /* should be more than enough space */
    MS_CHECK_ALLOC(layer->items, sizeof(char *), MS_FAILURE);

    layer->numitems = 0;
  }
  return MS_SUCCESS;
}

int LayerDefaultGetNumFeatures(layerObj *layer)
{
    rectObj extent;
    int status;
    int result;
    shapeObj shape;

    /* calculate layer extent */
    if (!MS_VALID_EXTENT(layer->extent)) {
        if (msLayerGetExtent(layer, &extent) != MS_SUCCESS) {
            msSetError(MS_MISCERR, "Unable to get layer extent", "LayerDefaultGetNumFeatures()");
            return -1;
        }
    }
    else
        extent = layer->extent;

    /* Cleanup any previous item selection */
    msLayerFreeItemInfo(layer);
    if (layer->items) {
        msFreeCharArray(layer->items, layer->numitems);
        layer->items = NULL;
        layer->numitems = 0;
    }

    status = msLayerWhichShapes(layer, extent, MS_FALSE);
    if (status == MS_DONE) { /* no overlap */
        return 0;
    }
    else if (status != MS_SUCCESS) {
        return -1;
    }

    result = 0;
    while ((status = msLayerNextShape(layer, &shape)) == MS_SUCCESS) {
        ++result;
    }

    return result;
}

int LayerDefaultAutoProjection(layerObj *layer, projectionObj* projection)
{
  msSetError(MS_MISCERR, "This data driver does not implement AUTO projection support", "LayerDefaultAutoProjection()");
  return MS_FAILURE;
}

int LayerDefaultSupportsCommonFilters(layerObj *layer)
{
  return MS_FALSE;
}

int LayerDefaultTranslateFilter(layerObj *layer, expressionObj *filter, char *filteritem) 
{
  if(!filter->string) return MS_SUCCESS; /* nothing to do, not an error */

  msSetError(MS_MISCERR, "This data driver does not implement filter translation support", "LayerDefaultTranslateFilter()");
  return MS_FAILURE;
}

int msLayerDefaultGetPaging(layerObj *layer)
{
  return MS_FALSE;
}

void msLayerDefaultEnablePaging(layerObj *layer, int value)
{
  return;
}

/************************************************************************/
/*                          LayerDefaultEscapeSQLParam                  */
/*                                                                      */
/*      Default function used to escape strings and avoid sql           */
/*      injection. Specific drivers should redefine if an escaping      */
/*      function is available in the driver.                            */
/************************************************************************/
char *LayerDefaultEscapeSQLParam(layerObj *layer, const char* pszString)
{
  char *pszEscapedStr=NULL;
  if (pszString) {
    int nSrcLen;
    char c;
    int i=0, j=0;
    nSrcLen = (int)strlen(pszString);
    pszEscapedStr = (char*) msSmallMalloc( 2 * nSrcLen + 1);
    for(i = 0, j = 0; i < nSrcLen; i++) {
      c = pszString[i];
      if (c == '\'') {
        pszEscapedStr[j++] = '\'';
        pszEscapedStr[j++] = '\'';
      } else if (c == '\\') {
        pszEscapedStr[j++] = '\\';
        pszEscapedStr[j++] = '\\';
      } else
        pszEscapedStr[j++] = c;
    }
    pszEscapedStr[j] = 0;
  }
  return pszEscapedStr;
}

/************************************************************************/
/*                          LayerDefaultEscapePropertyName              */
/*                                                                      */
/*      Return the property name in a properly escaped and quoted form. */
/************************************************************************/
char *LayerDefaultEscapePropertyName(layerObj *layer, const char* pszString)
{
  char* pszEscapedStr=NULL;
  int i, j = 0;

  if (layer && pszString && strlen(pszString) > 0) {
    int nLength = strlen(pszString);

    pszEscapedStr = (char*) msSmallMalloc( 1 + 2 * nLength + 1 + 1);
    pszEscapedStr[j++] = '"';

    for (i=0; i<nLength; i++) {
      char c = pszString[i];
      if (c == '"') {
        pszEscapedStr[j++] = '"';
        pszEscapedStr[j++] ='"';
      } else if (c == '\\') {
        pszEscapedStr[j++] = '\\';
        pszEscapedStr[j++] = '\\';
      } else
        pszEscapedStr[j++] = c;
    }
    pszEscapedStr[j++] = '"';
    pszEscapedStr[j++] = 0;

  }
  return pszEscapedStr;
}


/*
 * msConnectLayer
 *
 * This will connect layer object to the new layer type.
 * Caller is responsible to close previous layer correctly.
 * For Internal types the library_str is ignored, for PLUGIN it's
 * define what plugin to use. Returns MS_FAILURE or MS_SUCCESS.
 */
int msConnectLayer(layerObj *layer,
                   const int connectiontype,
                   const char *library_str)
{
  layer->connectiontype = connectiontype;
  /* For internal types, library_str is ignored */
  if (connectiontype == MS_PLUGIN) {
    int rv;
    msFree(layer->plugin_library);
    msFree(layer->plugin_library_original);

    layer->plugin_library_original = msStrdup(library_str);
    rv = msBuildPluginLibraryPath(&layer->plugin_library,
                                  layer->plugin_library_original,
                                  layer->map);
    if (rv != MS_SUCCESS) {
      return rv;
    }
  }
  return msInitializeVirtualTable(layer) ;
}

static int populateVirtualTable(layerVTableObj *vtable)
{
  assert(vtable != NULL);

  vtable->LayerSupportsCommonFilters = LayerDefaultSupportsCommonFilters;
  vtable->LayerTranslateFilter = LayerDefaultTranslateFilter;

  vtable->LayerInitItemInfo = LayerDefaultInitItemInfo;
  vtable->LayerFreeItemInfo = LayerDefaultFreeItemInfo;
  vtable->LayerOpen = LayerDefaultOpen;
  vtable->LayerIsOpen = LayerDefaultIsOpen;
  vtable->LayerWhichShapes = LayerDefaultWhichShapes;

  vtable->LayerNextShape = LayerDefaultNextShape;
  /* vtable->LayerResultsGetShape = LayerDefaultResultsGetShape; */
  vtable->LayerGetShape = LayerDefaultGetShape;
  vtable->LayerGetShapeCount = LayerDefaultGetShapeCount;
  vtable->LayerClose = LayerDefaultClose;
  vtable->LayerGetItems = LayerDefaultGetItems;
  vtable->LayerGetExtent = LayerDefaultGetExtent;

  vtable->LayerGetAutoStyle = LayerDefaultGetAutoStyle;
  vtable->LayerCloseConnection = LayerDefaultCloseConnection;
  vtable->LayerSetTimeFilter = msLayerMakePlainTimeFilter;

  vtable->LayerApplyFilterToLayer = msLayerApplyPlainFilterToLayer;

  vtable->LayerCreateItems = LayerDefaultCreateItems;

  vtable->LayerGetNumFeatures = LayerDefaultGetNumFeatures;

  vtable->LayerGetAutoProjection = LayerDefaultAutoProjection;

  vtable->LayerEscapeSQLParam = LayerDefaultEscapeSQLParam;

  vtable->LayerEscapePropertyName = LayerDefaultEscapePropertyName;

  vtable->LayerEnablePaging = msLayerDefaultEnablePaging;
  vtable->LayerGetPaging = msLayerDefaultGetPaging;

  return MS_SUCCESS;
}

static int createVirtualTable(layerVTableObj **vtable)
{
  *vtable = malloc(sizeof(**vtable));
  MS_CHECK_ALLOC(*vtable, sizeof(**vtable), MS_FAILURE);

  return populateVirtualTable(*vtable);
}

static int destroyVirtualTable(layerVTableObj **vtable)
{
  memset(*vtable, 0, sizeof(**vtable));
  msFree(*vtable);
  *vtable = NULL;
  return MS_SUCCESS;
}

int msInitializeVirtualTable(layerObj *layer)
{
  if (layer->vtable) {
    destroyVirtualTable(&layer->vtable);
  }
  createVirtualTable(&layer->vtable);

  if(layer->features && layer->connectiontype != MS_GRATICULE )
    layer->connectiontype = MS_INLINE;

  if(layer->tileindex && layer->connectiontype == MS_SHAPEFILE)
    layer->connectiontype = MS_TILED_SHAPEFILE;

  if(layer->type == MS_LAYER_RASTER && layer->connectiontype != MS_WMS
      && layer->connectiontype != MS_KERNELDENSITY)
    layer->connectiontype = MS_RASTER;

  switch(layer->connectiontype) {
    case(MS_INLINE):
      return(msINLINELayerInitializeVirtualTable(layer));
      break;
    case(MS_SHAPEFILE):
      return(msSHPLayerInitializeVirtualTable(layer));
      break;
    case(MS_TILED_SHAPEFILE):
      return(msTiledSHPLayerInitializeVirtualTable(layer));
      break;
    case(MS_OGR):
      return(msOGRLayerInitializeVirtualTable(layer));
      break;
    case(MS_POSTGIS):
      return(msPostGISLayerInitializeVirtualTable(layer));
      break;
    case(MS_WMS):
      /* WMS should be treated as a raster layer */
      return(msRASTERLayerInitializeVirtualTable(layer));
      break;
    case(MS_KERNELDENSITY):
      /* KERNELDENSITY should be treated as a raster layer */
      return(msRASTERLayerInitializeVirtualTable(layer));
      break;
    case(MS_ORACLESPATIAL):
      return(msOracleSpatialLayerInitializeVirtualTable(layer));
      break;
    case(MS_WFS):
      return(msWFSLayerInitializeVirtualTable(layer));
      break;
    case(MS_GRATICULE):
      return(msGraticuleLayerInitializeVirtualTable(layer));
      break;
    case(MS_RASTER):
      return(msRASTERLayerInitializeVirtualTable(layer));
      break;
    case(MS_PLUGIN):
      return(msPluginLayerInitializeVirtualTable(layer));
      break;
    case(MS_UNION):
      return(msUnionLayerInitializeVirtualTable(layer));
      break;
    case(MS_UVRASTER):
      return(msUVRASTERLayerInitializeVirtualTable(layer));
      break;
    case(MS_CONTOUR):
      return(msContourLayerInitializeVirtualTable(layer));
      break;      
    default:
      msSetError(MS_MISCERR, "Unknown connectiontype, it was %d", "msInitializeVirtualTable()", layer->connectiontype);
      return MS_FAILURE;
      break;
  }

  /* not reached */
  return MS_FAILURE;
}

/*
 * INLINE: Virtual table functions
 */

typedef struct {
  rectObj searchrect;
  int is_relative; /* relative coordinates? */
}
msINLINELayerInfo;

int msINLINELayerIsOpen(layerObj *layer)
{
  if (layer->layerinfo)
    return(MS_TRUE);
  else
    return(MS_FALSE);
}

msINLINELayerInfo *msINLINECreateLayerInfo(void)
{
  msINLINELayerInfo *layerinfo = msSmallMalloc(sizeof(msINLINELayerInfo));
  layerinfo->searchrect.minx = -1.0;
  layerinfo->searchrect.miny = -1.0;
  layerinfo->searchrect.maxx = -1.0;
  layerinfo->searchrect.maxy = -1.0;
  layerinfo->is_relative = MS_FALSE;
  return layerinfo;  
}

int msINLINELayerOpen(layerObj *layer)
{
  msINLINELayerInfo  *layerinfo;

  if (layer->layerinfo) {
    if (layer->debug) {
      msDebug("msINLINELayerOpen: Layer is already open!\n");
    }
    return MS_SUCCESS;  /* already open */
  }
  
  /*
  ** Initialize the layerinfo
  **/
  layerinfo = msINLINECreateLayerInfo();
  
  layer->currentfeature = layer->features; /* point to the begining of the feature list */

  layer->layerinfo = (void*)layerinfo;
  
  return(MS_SUCCESS);
}

int msINLINELayerClose(layerObj *layer)
{
  if (layer->layerinfo) {
    free(layer->layerinfo);
    layer->layerinfo = NULL;
  }

  return MS_SUCCESS;
}

int msINLINELayerWhichShapes(layerObj *layer, rectObj rect, int isQuery)
{
  msINLINELayerInfo *layerinfo = NULL;  
  layerinfo = (msINLINELayerInfo*) layer->layerinfo;

  layerinfo->searchrect = rect;
  layerinfo->is_relative = (layer->transform != MS_FALSE && layer->transform != MS_TRUE);
  
  return MS_SUCCESS;
}

/* Author: Cristoph Spoerri and Sean Gillies */
int msINLINELayerGetShape(layerObj *layer, shapeObj *shape, resultObj *record)
{
  int i=0;
  featureListNodeObjPtr current;

  int shapeindex = record->shapeindex; /* only index necessary */

  current = layer->features;
  while (current!=NULL && i!=shapeindex) {
    i++;
    current = current->next;
  }
  if (current == NULL) {
    msSetError(MS_SHPERR, "No inline feature with this index.", "msINLINELayerGetShape()");
    return MS_FAILURE;
  }

  if (msCopyShape(&(current->shape), shape) != MS_SUCCESS) {
    msSetError(MS_SHPERR, "Cannot retrieve inline shape. There some problem with the shape", "msINLINELayerGetShape()");
    return MS_FAILURE;
  }
  /* check for the expected size of the values array */
  if (layer->numitems > shape->numvalues) {
    shape->values = (char **)msSmallRealloc(shape->values, sizeof(char *)*(layer->numitems));
    for (i = shape->numvalues; i < layer->numitems; i++)
      shape->values[i] = msStrdup("");
  }
  msComputeBounds(shape);
  return MS_SUCCESS;
}

int msINLINELayerNextShape(layerObj *layer, shapeObj *shape)
{
  msINLINELayerInfo *layerinfo = NULL;  
  shapeObj * s;
  
  layerinfo = (msINLINELayerInfo*) layer->layerinfo;
  
  while (1) {

    if( ! (layer->currentfeature)) {
      /* out of features */
      return(MS_DONE);
    }

    s = &(layer->currentfeature->shape);
    layer->currentfeature = layer->currentfeature->next;
    msComputeBounds(s);

    if (layerinfo->is_relative || msRectOverlap(&s->bounds, &layerinfo->searchrect)) {
   
      msCopyShape(s, shape);

      /* check for the expected size of the values array */
      if (layer->numitems > shape->numvalues) {
        int i;
        shape->values = (char **)msSmallRealloc(shape->values, sizeof(char *)*(layer->numitems));
        for (i = shape->numvalues; i < layer->numitems; i++)
          shape->values[i] = msStrdup("");
        shape->numvalues = layer->numitems;
      }

      break;
    }
    
  }

  return(MS_SUCCESS);
}

int msINLINELayerGetNumFeatures(layerObj *layer)
{
  int i = 0;
  featureListNodeObjPtr current;

  current = layer->features;
  while (current != NULL) {
    i++;
    current = current->next;
  }
  return i;
}



/*
Returns an escaped string
*/
char  *msLayerEscapeSQLParam(layerObj *layer, const char*pszString)
{
  if ( ! layer->vtable) {
    int rv =  msInitializeVirtualTable(layer);
    if (rv != MS_SUCCESS)
      return "";
  }
  return layer->vtable->LayerEscapeSQLParam(layer, pszString);
}

char  *msLayerEscapePropertyName(layerObj *layer, const char*pszString)
{
  if ( ! layer->vtable) {
    int rv =  msInitializeVirtualTable(layer);
    if (rv != MS_SUCCESS)
      return "";
  }
  return layer->vtable->LayerEscapePropertyName(layer, pszString);
}


int
msINLINELayerInitializeVirtualTable(layerObj *layer)
{
  assert(layer != NULL);
  assert(layer->vtable != NULL);

  /* layer->vtable->LayerInitItemInfo, use default */
  /* layer->vtable->LayerFreeItemInfo, use default */
  layer->vtable->LayerOpen = msINLINELayerOpen;
  layer->vtable->LayerIsOpen = msINLINELayerIsOpen;
  layer->vtable->LayerWhichShapes = msINLINELayerWhichShapes;
  layer->vtable->LayerNextShape = msINLINELayerNextShape;
  /* layer->vtable->LayerGetShapeCount, use default */
  layer->vtable->LayerGetShape = msINLINELayerGetShape;
  layer->vtable->LayerClose = msINLINELayerClose;
  /* layer->vtable->LayerGetItems, use default */

  /*
   * Original code contained following
   * TODO: need to compute extents
   */
  /* layer->vtable->LayerGetExtent, use default */

  /* layer->vtable->LayerGetAutoStyle, use default */
  /* layer->vtable->LayerCloseConnection, use default */
  layer->vtable->LayerSetTimeFilter = msLayerMakeBackticsTimeFilter;

  /* layer->vtable->LayerApplyFilterToLayer, use default */

  /* layer->vtable->LayerCreateItems, use default */
  layer->vtable->LayerGetNumFeatures = msINLINELayerGetNumFeatures;

  /*layer->vtable->LayerEscapeSQLParam, use default*/
  /*layer->vtable->LayerEscapePropertyName, use default*/

  /* layer->vtable->LayerEnablePaging, use default */
  /* layer->vtable->LayerGetPaging, use default */

  return MS_SUCCESS;
}