UTFGRID: implement escaping of item and data values

mapserver.h

@@ -2158,6 +2158,7 @@ void msPopulateTextSymbolForLabelAndString(textSymbolObj *ts, labelObj *l, char
   MS_DLL_EXPORT int msEncodeChar(const char);
   MS_DLL_EXPORT char *msEncodeUrlExcept(const char*, const char);
   MS_DLL_EXPORT char *msEncodeUrl(const char*);
+  MS_DLL_EXPORT char *msEscapeJSonString(const char* pszJSonString);
   MS_DLL_EXPORT char *msEncodeHTMLEntities(const char *string);
   MS_DLL_EXPORT void msDecodeHTMLEntities(const char *string);
   MS_DLL_EXPORT int msIsXMLTagValid(const char *string);
@@ -2580,6 +2581,7 @@ void msPopulateTextSymbolForLabelAndString(textSymbolObj *ts, labelObj *l, char
   MS_DLL_EXPORT int msGetLabelStatus(mapObj *map, layerObj *layer, shapeObj *shape, labelObj *lbl);
   MS_DLL_EXPORT int msAdjustImage(rectObj rect, int *width, int *height);
   MS_DLL_EXPORT char *msEvalTextExpression(expressionObj *expr, shapeObj *shape);
+  MS_DLL_EXPORT char *msEvalTextExpressionJSonEscape(expressionObj *expr, shapeObj *shape);
   MS_DLL_EXPORT double msAdjustExtent(rectObj *rect, int width, int height);
   MS_DLL_EXPORT int msConstrainExtent(rectObj *bounds, rectObj *rect, double overlay);
   MS_DLL_EXPORT int *msGetLayersIndexByGroup(mapObj *map, char *groupname, int *nCount);

mapstring.c

@@ -1125,7 +1125,7 @@ char *msEncodeUrl(const char *data)
 
 char *msEncodeUrlExcept(const char *data, const char except)
 {
-  char *hex = "0123456789ABCDEF";
+  static const char *hex = "0123456789ABCDEF";
   const char *i;
   char  *j, *code;
   int   inc;
@@ -1155,6 +1155,77 @@ char *msEncodeUrlExcept(const char *data, const char except)
   return code;
 }
 
+/************************************************************************/
+/*                            msEscapeJSonString()                      */
+/************************************************************************/
+
+/* The input (and output) string are not supposed to start/end with double */
+/* quote characters. It is the responsibility of the caller to do that. */
+char* msEscapeJSonString(const char* pszJSonString)
+{
+    /* Worst case is one character to become \uABCD so 6 characters */
+    char* pszRet;
+    int i = 0, j = 0;
+    static const char* pszHex = "0123456789ABCDEF";
+
+    pszRet = (char*) msSmallMalloc(strlen(pszJSonString) * 6 + 1);
+    /* From http://www.json.org/ */
+    for(i = 0; pszJSonString[i] != '\0'; i++)
+    {
+        unsigned char ch = pszJSonString[i];
+        if( ch == '\b' )
+        {
+            pszRet[j++] = '\\';
+            pszRet[j++] = 'b';
+        }
+        else if( ch == '\f' )
+        {
+            pszRet[j++] = '\\';
+            pszRet[j++] = 'f';
+        }
+        else if( ch == '\n' )
+        {
+            pszRet[j++] = '\\';
+            pszRet[j++] = 'n';
+        }
+        else if( ch == '\r' )
+        {
+            pszRet[j++] = '\\';
+            pszRet[j++] = 'r';
+        }
+        else if( ch == '\t' )
+        {
+            pszRet[j++] = '\\';
+            pszRet[j++] = 't';
+        }
+        else if( ch < 32 )
+        {
+            pszRet[j++] = '\\';
+            pszRet[j++] = 'u';
+            pszRet[j++] = '0';
+            pszRet[j++] = '0';
+            pszRet[j++] = pszHex[ch / 16];
+            pszRet[j++] = pszHex[ch % 16];
+        }
+        else if( ch == '"' )
+        {
+            pszRet[j++] = '\\';
+            pszRet[j++] = '"';
+        }
+        else if( ch == '\\' )
+        {
+            pszRet[j++] = '\\';
+            pszRet[j++] = '\\';
+        }
+        else
+        {
+            pszRet[j++] = ch;
+        }
+    }
+    pszRet[j] = '\0';
+    return pszRet;
+}
+
 /* msEncodeHTMLEntities()
 **
 ** Return a copy of string after replacing some problematic chars with their

maputfgrid.cpp

@@ -267,7 +267,7 @@ band_type addToTable(UTFGridRenderer *r, shapeObj *p)
   utfvalue = encodeForRendering(utfvalue);
 
   /* Datas are added to the table */
-  r->data->table[r->data->counter].datavalues = msEvalTextExpression(&r->utflayer->utfdata, p);
+  r->data->table[r->data->counter].datavalues = msEvalTextExpressionJSonEscape(&r->utflayer->utfdata, p);
 
   /* If UTFITEM is set in the mapfiles we add its value to the table */
   if(r->useutfitem)
@@ -366,6 +366,7 @@ int utfgridSaveImage(imageObj *img, mapObj *map, FILE *fp, outputFormatObj *form
 {
   int row, col, i, imgheight, imgwidth;
   band_type pixelid;
+  char* pszEscaped;
 
   UTFGridRenderer *renderer = UTFGRID_RENDERER(img);
 
@@ -412,7 +413,11 @@ int utfgridSaveImage(imageObj *img, mapObj *map, FILE *fp, outputFormatObj *form
       fprintf(fp,",");
 
     if(renderer->useutfitem)
-      fprintf(fp,"\"%s\"", renderer->data->table[i].itemvalue);
+    {
+      pszEscaped = msEscapeJSonString(renderer->data->table[i].itemvalue);
+      fprintf(fp,"\"%s\"", pszEscaped);
+      msFree(pszEscaped);
+    }
     /* If no UTFITEM specified use the serial ID as the key */
     else
       fprintf(fp,"\"%i\"", renderer->data->table[i].serialid);
@@ -427,10 +432,15 @@ int utfgridSaveImage(imageObj *img, mapObj *map, FILE *fp, outputFormatObj *form
         fprintf(fp,",");
 
       if(renderer->useutfitem)
-        fprintf(fp,"\"%s\":", renderer->data->table[i].itemvalue);
+      {
+        pszEscaped = msEscapeJSonString(renderer->data->table[i].itemvalue);
+        fprintf(fp,"\"%s\":", pszEscaped);
+        msFree(pszEscaped);
+      }
       /* If no UTFITEM specified use the serial ID as the key */
       else
         fprintf(fp,"\"%i\":", renderer->data->table[i].serialid);
+
       fprintf(fp,"%s", renderer->data->table[i].datavalues);
     }
   }

maputil.c

@@ -611,7 +611,8 @@ int msShapeGetClass(layerObj *layer, mapObj *map, shapeObj *shape, int *classgro
   return(-1); /* no match */
 }
 
-char *msEvalTextExpression(expressionObj *expr, shapeObj *shape)
+static
+char *msEvalTextExpressionInternal(expressionObj *expr, shapeObj *shape, int bJSonEscape)
 {
   char *result=NULL;
 
@@ -620,6 +621,7 @@ char *msEvalTextExpression(expressionObj *expr, shapeObj *shape)
   switch(expr->type) {
     case(MS_STRING): {
       char *target=NULL;
+      char *pszEscaped;
       tokenListNodeObjPtr node=NULL;
       tokenListNodeObjPtr nextNode=NULL;
 
@@ -632,7 +634,12 @@ char *msEvalTextExpression(expressionObj *expr, shapeObj *shape)
           if(node->token == MS_TOKEN_BINDING_DOUBLE || node->token == MS_TOKEN_BINDING_INTEGER || node->token == MS_TOKEN_BINDING_STRING || node->token == MS_TOKEN_BINDING_TIME) {
             target = (char *) msSmallMalloc(strlen(node->tokenval.bindval.item) + 3);
             sprintf(target, "[%s]", node->tokenval.bindval.item);
-            result = msReplaceSubstring(result, target, shape->values[node->tokenval.bindval.index]);
+            if( bJSonEscape )
+                pszEscaped = msEscapeJSonString(shape->values[node->tokenval.bindval.index]);
+            else
+                pszEscaped = msStrdup(shape->values[node->tokenval.bindval.index]);
+            result = msReplaceSubstring(result, target, pszEscaped);
+            msFree(pszEscaped);
             msFree(target);
           }
           node = nextNode;
@@ -673,6 +680,16 @@ char *msEvalTextExpression(expressionObj *expr, shapeObj *shape)
   return result;
 }
 
+char *msEvalTextExpressionJSonEscape(expressionObj *expr, shapeObj *shape)
+{
+    return msEvalTextExpressionInternal(expr, shape, TRUE);
+}
+
+char *msEvalTextExpression(expressionObj *expr, shapeObj *shape)
+{
+    return msEvalTextExpressionInternal(expr, shape, FALSE);
+}
+
 char* msShapeGetLabelAnnotation(layerObj *layer, shapeObj *shape, labelObj *lbl) {
   assert(shape && lbl);
   if(lbl->text.string) {