fixed problem with 0x2d in Char Range (bug #420596) added regression test

* xmlregexp.c: fixed problem with 0x2d in Char Range (bug #420596)
* test/regexp/bug420596, result/regexp/bug420596: added regression
  test for this

svn path=/trunk/; revision=3594

ChangeLog

@@ -1,3 +1,9 @@
+Wed Mar 21 21:20:48 HKT 2007 William Brack <wbrack@mmm.com.hk>
+
+	* xmlregexp.c: fixed problem with 0x2d in Char Range (bug #420596)
+	* test/regexp/bug420596, result/regexp/bug420596: added regression
+	  test for this
+
 Wed Mar 21 14:23:08 HKT 2007 William Brack <wbrack@mmm.com.hk>
 
 	* HTMLparser.c: fixed memory access error on parsing of meta data

result/regexp/bug420596

@@ -0,0 +1,10 @@
+Regexp: (\+|-)(0[0-9]|1[0-1])
++01: Ok
+-01: Ok
++10: Ok
+-10: Ok
+Regexp: [+-](0[0-9]|1[0-1])
++01: Ok
+-01: Ok
++10: Ok
+-10: Ok

test/regexp/bug420596

@@ -0,0 +1,10 @@
+=>(\+|-)(0[0-9]|1[0-1])
++01
+-01
++10
+-10
+=>[+-](0[0-9]|1[0-1])
++01
+-01
++10
+-10

xmlregexp.c

@@ -54,6 +54,11 @@
 #define CUR_SCHAR(s, l) xmlStringCurrentChar(NULL, s, &l)
 #define NEXTL(l) ctxt->cur += l;
 #define XML_REG_STRING_SEPARATOR '|'
+/*
+ * Need PREV to check on a '-' within a Character Group. May only be used
+ * when it's guaranteed that cur is not at the beginning of ctxt->string!
+ */
+#define PREV (ctxt->cur[-1])
 
 /**
  * TODO:
@@ -4853,10 +4858,15 @@ xmlFAParseCharRange(xmlRegParserCtxtPtr ctxt) {
 	ERROR("Expecting a char range");
 	return;
     }
+    /*
+     * Since we are "inside" a range, we can assume ctxt->cur is past
+     * the start of ctxt->string, and PREV should be safe
+     */
+    if ((start == '-') && (NXT(1) != ']') && (PREV != '[') && (PREV != '^')) {
 	NEXTL(len);
-    if (start == '-') {
 	return;
     }
+    NEXTL(len);
     cur = CUR;
     if ((cur != '-') || (NXT(1) == ']')) {
         xmlRegAtomAddRange(ctxt, ctxt->atom, ctxt->neg,