Fix options set and reset at top level bug.

git-svn-id: svn://vcs.exim.org/pcre/code/trunk@472 2f5784b3-3f2a-0410-8824-cb99058d5e15

6 files changed, 98 insertions, 2 deletions

diff --git a/ChangeLog b/ChangeLog
index 749a674..d7adfca 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -8,6 +8,13 @@ Version 8.01 11-Dec-09
     particular, this includes all (DEFINE) patterns), a call to pcre_study() 
     computed the wrong minimum data length (which is of course zero for such 
     subpatterns).
+    
+2.  For patterns such as (?i)a(?-i)b|c where an option setting at the start of 
+    the pattern is reset in the first branch, pcre_compile() failed with
+    "internal error: code overflow at offset...". This happened only when
+    the reset was to the original external option setting. (An optimization 
+    abstracts leading options settings into an external setting, which was the 
+    cause of this.)
 
 
 Version 8.00 19-Oct-09
diff --git a/pcre_compile.c b/pcre_compile.c
index c360c43..0605a6e 100644
--- a/pcre_compile.c
+++ b/pcre_compile.c
@@ -5248,7 +5248,7 @@ we set the flag only if there is a literal "\r" or "\n" in the class. */
             {
             cd->external_options = newoptions;
             }
-         else
+          else
             {
             if ((options & PCRE_IMS) != (newoptions & PCRE_IMS))
               {
@@ -5783,6 +5783,7 @@ int branchfirstbyte, branchreqbyte;
 int length;
 int orig_bracount;
 int max_bracount;
+int old_external_options = cd->external_options;
 branch_chain bc;
 
 bc.outer = bcptr;
@@ -5859,6 +5860,15 @@ for (;;)
     return FALSE;
     }
 
+  /* If the external options have changed during this branch, it means that we
+  are at the top level, and a leading option setting has been encountered. We
+  need to re-set the original option values to take account of this so that,
+  during the pre-compile phase, we know to allow for a re-set at the start of
+  subsequent branches. */
+
+  if (old_external_options != cd->external_options)
+    oldims = cd->external_options & PCRE_IMS;
+
   /* Keep the highest bracket count in case (?| was used and some branch
   has fewer than the rest. */
 
@@ -5969,7 +5979,7 @@ for (;;)
     PUT(code, 1, code - start_bracket);
     code += 1 + LINK_SIZE;
 
-    /* Resetting option if needed */
+    /* Reset options if needed. */
 
     if ((options & PCRE_IMS) != oldims && *ptr == CHAR_RIGHT_PARENTHESIS)
       {
diff --git a/testdata/testinput1 b/testdata/testinput1
index 6cacbb5..48cc5a9 100644
--- a/testdata/testinput1
+++ b/testdata/testinput1
@@ -4067,4 +4067,11 @@
 /^%((?(?=[a])[^%])|b)*%$/
     %ab%
 
+/(?i)a(?-i)b|c/
+    XabX
+    XAbX
+    CcC 
+    ** Failers
+    XABX   
+
 /-- End of testinput1 --/
diff --git a/testdata/testinput2 b/testdata/testinput2
index c49b94f..8e1a5e8 100644
--- a/testdata/testinput2
+++ b/testdata/testinput2
@@ -3175,4 +3175,15 @@ a random value. /Ix
 /()i(?(1)a)/SI 
     ia
 
+/(?i)a(?-i)b|c/BZ
+    XabX
+    XAbX
+    CcC 
+    ** Failers
+    XABX   
+
+/(?i)a(?s)b|c/BZ
+
+/(?i)a(?s-i)b|c/BZ
+
 /-- End of testinput2 --/
diff --git a/testdata/testoutput1 b/testdata/testoutput1
index a2a6dd4..6c28602 100644
--- a/testdata/testoutput1
+++ b/testdata/testoutput1
@@ -6649,4 +6649,16 @@ No match
  0: %ab%
  1: 
 
+/(?i)a(?-i)b|c/
+    XabX
+ 0: ab
+    XAbX
+ 0: Ab
+    CcC 
+ 0: c
+    ** Failers
+No match
+    XABX   
+No match
+
 /-- End of testinput1 --/
diff --git a/testdata/testoutput2 b/testdata/testoutput2
index be968da..83aef94 100644
--- a/testdata/testoutput2
+++ b/testdata/testoutput2
@@ -10486,4 +10486,53 @@ Starting byte set: i
  0: ia
  1: 
 
+/(?i)a(?-i)b|c/BZ
+------------------------------------------------------------------
+        Bra
+     NC a
+     00 Opt
+        b
+        Alt
+     00 Opt
+        c
+        Ket
+        End
+------------------------------------------------------------------
+    XabX
+ 0: ab
+    XAbX
+ 0: Ab
+    CcC 
+ 0: c
+    ** Failers
+No match
+    XABX   
+No match
+
+/(?i)a(?s)b|c/BZ
+------------------------------------------------------------------
+        Bra
+     NC a
+     05 Opt
+     NC b
+        Alt
+     05 Opt
+     NC c
+        Ket
+        End
+------------------------------------------------------------------
+
+/(?i)a(?s-i)b|c/BZ
+------------------------------------------------------------------
+        Bra
+     NC a
+     04 Opt
+        b
+        Alt
+     04 Opt
+        c
+        Ket
+        End
+------------------------------------------------------------------
+
 /-- End of testinput2 --/