Fix incorrect error for patterns like /(?2)[]a()b](abc)/

git-svn-id: svn://vcs.exim.org/pcre/code/trunk@340 2f5784b3-3f2a-0410-8824-cb99058d5e15

4 files changed, 94 insertions, 1 deletions

diff --git a/ChangeLog b/ChangeLog
index 8199744..5b55099 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -62,6 +62,15 @@ Version 7.7 05-Mar-08
     (a) A lone ] character is dis-allowed (Perl treats it as data).
     (b) A back reference to an unmatched subpattern matches an empty string 
         (Perl fails the current match path).
+        
+14. A pattern such as /(?2)[]a()b](abc)/ which had a forward reference to a 
+    non-existent subpattern following a character class starting with ']' and
+    containing () gave an internal compiling error instead of "reference to
+    non-existent subpattern". Fortunately, when the pattern did exist, the
+    compiled code was correct. (When scanning forwards to check for the 
+    existencd of the subpattern, it was treating the data ']' as terminating
+    the class, so got the count wrong. When actually compiling, the reference 
+    was subsequently set up correctly.)
 
 
 Version 7.6 28-Jan-08
diff --git a/pcre_compile.c b/pcre_compile.c
index 9b10356..81a76b2 100644
--- a/pcre_compile.c
+++ b/pcre_compile.c
@@ -1008,10 +1008,33 @@ for (; *ptr != 0; ptr++)
     continue;
     }
 
-  /* Skip over character classes */
+  /* Skip over character classes; this logic must be similar to the way they
+  are handled for real. If the first character is '^', skip it. Also, if the
+  first few characters (either before or after ^) are \Q\E or \E we skip them
+  too. This makes for compatibility with Perl. */
 
   if (*ptr == '[')
     {
+    BOOL negate_class = FALSE;
+    for (;;)
+      {
+      int c = *(++ptr);
+      if (c == '\\')
+        {
+        if (ptr[1] == 'E') ptr++;
+          else if (strncmp((const char *)ptr+1, "Q\\E", 3) == 0) ptr += 3;
+            else break;
+        }
+      else if (!negate_class && c == '^')
+        negate_class = TRUE;
+      else break;
+      }
+
+    /* If the next character is ']', it is a data character that must be
+    skipped. */
+    
+    if (ptr[1] == ']') ptr++;  
+ 
     while (*(++ptr) != ']')
       {
       if (*ptr == 0) return -1;
diff --git a/testdata/testinput2 b/testdata/testinput2
index 52d4ef8..6c29b39 100644
--- a/testdata/testinput2
+++ b/testdata/testinput2
@@ -2667,4 +2667,29 @@ a random value. /Ix
 /TA]/<JS>
     The ACTA] comes 
 
+/(?2)[]a()b](abc)/
+    abcbabc
+
+/(?2)[^]a()b](abc)/
+    abcbabc
+
+/(?1)[]a()b](abc)/
+    abcbabc
+    ** Failers 
+    abcXabc
+
+/(?1)[^]a()b](abc)/
+    abcXabc
+    ** Failers 
+    abcbabc
+
+/(?2)[]a()b](abc)(xyz)/
+    xyzbabcxyz
+
+/(?&N)[]a(?<N>)](?<M>abc)/
+   abc<abc
+
+/(?&N)[]a(?<N>)](abc)/
+   abc<abc
+
 / End of testinput2 /
diff --git a/testdata/testoutput2 b/testdata/testoutput2
index 783e383..a2b9b8b 100644
--- a/testdata/testoutput2
+++ b/testdata/testoutput2
@@ -9545,4 +9545,40 @@ No match
 /TA]/<JS>
 Failed: ] is an invalid data character in JavaScript compatibility mode at offset 2
 
+/(?2)[]a()b](abc)/
+Failed: reference to non-existent subpattern at offset 3
+
+/(?2)[^]a()b](abc)/
+Failed: reference to non-existent subpattern at offset 3
+
+/(?1)[]a()b](abc)/
+    abcbabc
+ 0: abcbabc
+ 1: abc
+    ** Failers 
+No match
+    abcXabc
+No match
+
+/(?1)[^]a()b](abc)/
+    abcXabc
+ 0: abcXabc
+ 1: abc
+    ** Failers 
+No match
+    abcbabc
+No match
+
+/(?2)[]a()b](abc)(xyz)/
+    xyzbabcxyz
+ 0: xyzbabcxyz
+ 1: abc
+ 2: xyz
+
+/(?&N)[]a(?<N>)](?<M>abc)/
+Failed: reference to non-existent subpattern at offset 4
+
+/(?&N)[]a(?<N>)](abc)/
+Failed: reference to non-existent subpattern at offset 4
+
 / End of testinput2 /