Bug#461618: Acknowledgement (In SAX-like parsers, character entities should be presented as normal characters)

[Stijn van Drongelen]

tags 461618 +patch
thanks

A patch fixing this issue is attached. It basically encodes the UCS-4
entity code as UTF-8. It certainly looks a bit hacky, but at least it
seems to do the job properly.

Before this patch, the WBXML code for "ENTITY 160" (01 81 20)
translated to the string " ". After this patch, it translated to
character codes C2 A0, which is UTF-8 for the non-breaking space (in
UCS-4: 00 00 00 A0). The charachters-handler of the parser will only
recieve UTF-8 strings, like it should.

Sincerely,

Stijn van Drongelen

diff --git a/src/wbxml_parser.c b/src/wbxml_parser.c
index c022e00..bea2062 100644
--- a/src/wbxml_parser.c
+++ b/src/wbxml_parser.c
@@ -43,6 +43,7 @@
  */
 
 #include "wbxml.h"
+#include <assert.h>
 
 
 /* Memory management related defines */
@@ -56,10 +57,6 @@
 /** For unknown Tag Name or Attribute Name (in Best Effort Mode) */
 #define WBXML_PARSER_UNKNOWN_STRING ((WB_UTINY *)"unknown")
 
-/** If you want to modify this define, change the 'entcode' variable length in parse_entity() too please */
-#define WBXML_PARSER_MAX_ENTITY_CODE 999999
-
-
 /**
  * @brief The WBXML Application Token types
  */
@@ -1661,7 +1658,6 @@ static WBXMLError parse_extension(WBXMLParser *parser, WBXMLTokenType code_space
  */
 static WBXMLError parse_entity(WBXMLParser *parser, WBXMLBuffer **result)
 {
-    WB_TINY    entity[10];
     WB_ULONG   code   = 0;
     WBXMLError ret    = WBXML_OK;
   
@@ -1674,23 +1670,44 @@ static WBXMLError parse_entity(WBXMLParser *parser, WBXMLBuffer **result)
         return ret;
     }
   
-    /* Build Entity */
-    if ( code > WBXML_PARSER_MAX_ENTITY_CODE )  {
-        return WBXML_ERROR_ENTITY_CODE_OVERFLOW;
-    }
-  
-    /**
-     * WARNING: If you change the entity variable length (10 chars), change too
-     *          'WBXML_PARSER_MAX_ENTITY_CODE' defined in this file !
+    /*
+     * Convert the UCS-4 code to a UTF-8 encoded string.
      */
-    sprintf(entity, "&#%u;", code);
 
-    /* Create result buffer */
-    if ( (*result = wbxml_buffer_create_from_cstr(entity)) == NULL ) {
-        return WBXML_ERROR_NOT_ENOUGH_MEMORY;
+    assert(code < 0x80000000);
+
+    if (code < 0x80)
+    {
+        /* For codes under 0x80, we don't need any fancy formatting. */
+        WB_TINY entity[2] = {(WB_TINY)code, 0};
+
+        /* Create result buffer */
+        if ( (*result = wbxml_buffer_create_from_cstr(entity)) == NULL ) {
+            return WBXML_ERROR_NOT_ENOUGH_MEMORY;
+        }
+      
+        return WBXML_OK;
+    }
+    else
+    {
+        WB_TINY masks[5] = {0xFC, 0xF8, 0xF0, 0xE0, 0xC0};
+        WB_TINY entity[7] = {0, 0, 0, 0, 0, 0, 0};
+
+        int index = 5;
+        while (code >= 0x40)
+        {
+            entity[index] = 0x80 | (code & 0x3F);
+            code >>= 6; index--;
+        }
+        entity[index] = masks[index] | code;
+
+        /* Create result buffer */
+        if ( (*result = wbxml_buffer_create_from_cstr(entity + index)) == NULL ) {
+            return WBXML_ERROR_NOT_ENOUGH_MEMORY;
+        }
+      
+        return WBXML_OK;        
     }
-  
-  return WBXML_OK;
 }