Preparation code for future (*MARK) support.

git-svn-id: svn://vcs.exim.org/pcre/code/trunk@501 2f5784b3-3f2a-0410-8824-cb99058d5e15

2 files changed, 23 insertions, 11 deletions

diff --git a/ChangeLog b/ChangeLog
index f14172c..20ee4dc 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -45,6 +45,12 @@ Version 8.02 01-Mar-2010
     was called as a "subroutine", or in an assertion. Perl 5.11 documents that 
     \K is "not well defined" if used in an assertion. PCRE now accepts it if 
     the assertion is positive, but not if it is negative. 
+    
+12. Change 11 fortuitously reduced the size of the stack frame used in the
+    "match()" function of pcre_exec.c by one pointer. Forthcoming 
+    implementation of support for (*MARK) will need an extra pointer on the 
+    stack; I have reserved it now, so that the stack frame size does not
+    decrease.
 
 
 Version 8.01 19-Jan-2010
diff --git a/pcre_exec.c b/pcre_exec.c
index 2734723..0f3176a 100644
--- a/pcre_exec.c
+++ b/pcre_exec.c
@@ -249,7 +249,7 @@ enum { RM1=1, RM2,  RM3,  RM4,  RM5,  RM6,  RM7,  RM8,  RM9,  RM10,
 
 /* These versions of the macros use the stack, as normal. There are debugging
 versions and production versions. Note that the "rw" argument of RMATCH isn't
-actuall used in this definition. */
+actually used in this definition. */
 
 #ifndef NO_RECURSE
 #define REGISTER register
@@ -258,7 +258,7 @@ actuall used in this definition. */
 #define RMATCH(ra,rb,rc,rd,re,rf,rg,rw) \
   { \
   printf("match() called in line %d\n", __LINE__); \
-  rrc = match(ra,rb,mstart,rc,rd,re,rf,rg,rdepth+1); \
+  rrc = match(ra,rb,mstart,markptr,rc,rd,re,rf,rg,rdepth+1); \
   printf("to line %d\n", __LINE__); \
   }
 #define RRETURN(ra) \
@@ -268,7 +268,7 @@ actuall used in this definition. */
   }
 #else
 #define RMATCH(ra,rb,rc,rd,re,rf,rg,rw) \
-  rrc = match(ra,rb,mstart,rc,rd,re,rf,rg,rdepth+1)
+  rrc = match(ra,rb,mstart,markptr,rc,rd,re,rf,rg,rdepth+1)
 #define RRETURN(ra) return ra
 #endif
 
@@ -288,6 +288,7 @@ argument of match(), which never changes. */
   newframe->Xeptr = ra;\
   newframe->Xecode = rb;\
   newframe->Xmstart = mstart;\
+  newframe->Xmarkptr = markptr;\
   newframe->Xoffset_top = rc;\
   newframe->Xims = re;\
   newframe->Xeptrb = rf;\
@@ -325,6 +326,7 @@ typedef struct heapframe {
   USPTR Xeptr;
   const uschar *Xecode;
   USPTR Xmstart;
+  USPTR Xmarkptr;
   int Xoffset_top;
   long int Xims;
   eptrblock *Xeptrb;
@@ -432,6 +434,7 @@ Arguments:
    ecode       pointer to current position in compiled code
    mstart      pointer to the current match start position (can be modified
                  by encountering \K)
+   markptr     pointer to the most recent MARK name, or NULL
    offset_top  current top pointer
    md          pointer to "static" info for the match
    ims         current /i, /m, and /s options
@@ -450,9 +453,9 @@ Returns:       MATCH_MATCH if matched            )  these values are >= 0
 */
 
 static int
-match(REGISTER USPTR eptr, REGISTER const uschar *ecode, USPTR mstart,
-  int offset_top, match_data *md, unsigned long int ims, eptrblock *eptrb,
-  int flags, unsigned int rdepth)
+match(REGISTER USPTR eptr, REGISTER const uschar *ecode, USPTR mstart, USPTR
+  markptr, int offset_top, match_data *md, unsigned long int ims,
+  eptrblock *eptrb, int flags, unsigned int rdepth)
 {
 /* These variables do not need to be preserved over recursion in this function,
 so they can be ordinary variables in all cases. Mark some of them with
@@ -480,6 +483,7 @@ frame->Xprevframe = NULL;            /* Marks the top level */
 frame->Xeptr = eptr;
 frame->Xecode = ecode;
 frame->Xmstart = mstart;
+frame->Xmarkptr = markptr;
 frame->Xoffset_top = offset_top;
 frame->Xims = ims;
 frame->Xeptrb = eptrb;
@@ -495,6 +499,7 @@ HEAP_RECURSE:
 #define eptr               frame->Xeptr
 #define ecode              frame->Xecode
 #define mstart             frame->Xmstart
+#define markptr            frame->Xmarkptr
 #define offset_top         frame->Xoffset_top
 #define ims                frame->Xims
 #define eptrb              frame->Xeptrb
@@ -1113,11 +1118,11 @@ for (;;)
       {
       RMATCH(eptr, ecode + 1 + LINK_SIZE, offset_top, md, ims, NULL, 0,
         RM4);
-      if (rrc == MATCH_MATCH) 
+      if (rrc == MATCH_MATCH)
         {
         mstart = md->start_match_ptr;   /* In case \K reset it */
         break;
-        } 
+        }
       if (rrc != MATCH_NOMATCH && rrc != MATCH_THEN) RRETURN(rrc);
       ecode += GET(ecode, 1);
       }
@@ -1327,11 +1332,11 @@ for (;;)
     do
       {
       RMATCH(eptr, ecode + 1 + LINK_SIZE, offset_top, md, ims, eptrb, 0, RM7);
-      if (rrc == MATCH_MATCH) 
+      if (rrc == MATCH_MATCH)
         {
         mstart = md->start_match_ptr;
         break;
-        } 
+        }
       if (rrc != MATCH_NOMATCH && rrc != MATCH_THEN) RRETURN(rrc);
       ecode += GET(ecode,1);
       }
@@ -5658,7 +5663,8 @@ for(;;)
   md->start_match_ptr = start_match;
   md->start_used_ptr = start_match;
   md->match_call_count = 0;
-  rc = match(start_match, md->start_code, start_match, 2, md, ims, NULL, 0, 0);
+  rc = match(start_match, md->start_code, start_match, NULL, 2, md, ims, NULL,
+    0, 0);
   if (md->hitend && start_partial == NULL) start_partial = md->start_used_ptr;
 
   switch(rc)