symbian-qemu-0.9.1-12/python-2.6.1/Modules/_sre.c
changeset 1 2fb8b9db1c86
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/symbian-qemu-0.9.1-12/python-2.6.1/Modules/_sre.c	Fri Jul 31 15:01:17 2009 +0100
@@ -0,0 +1,3904 @@
+/*
+ * Secret Labs' Regular Expression Engine
+ *
+ * regular expression matching engine
+ *
+ * partial history:
+ * 1999-10-24 fl  created (based on existing template matcher code)
+ * 2000-03-06 fl  first alpha, sort of
+ * 2000-08-01 fl  fixes for 1.6b1
+ * 2000-08-07 fl  use PyOS_CheckStack() if available
+ * 2000-09-20 fl  added expand method
+ * 2001-03-20 fl  lots of fixes for 2.1b2
+ * 2001-04-15 fl  export copyright as Python attribute, not global
+ * 2001-04-28 fl  added __copy__ methods (work in progress)
+ * 2001-05-14 fl  fixes for 1.5.2 compatibility
+ * 2001-07-01 fl  added BIGCHARSET support (from Martin von Loewis)
+ * 2001-10-18 fl  fixed group reset issue (from Matthew Mueller)
+ * 2001-10-20 fl  added split primitive; reenable unicode for 1.6/2.0/2.1
+ * 2001-10-21 fl  added sub/subn primitive
+ * 2001-10-24 fl  added finditer primitive (for 2.2 only)
+ * 2001-12-07 fl  fixed memory leak in sub/subn (Guido van Rossum)
+ * 2002-11-09 fl  fixed empty sub/subn return type
+ * 2003-04-18 mvl fully support 4-byte codes
+ * 2003-10-17 gn  implemented non recursive scheme
+ *
+ * Copyright (c) 1997-2001 by Secret Labs AB.  All rights reserved.
+ *
+ * This version of the SRE library can be redistributed under CNRI's
+ * Python 1.6 license.  For any other use, please contact Secret Labs
+ * AB (info@pythonware.com).
+ *
+ * Portions of this engine have been developed in cooperation with
+ * CNRI.  Hewlett-Packard provided funding for 1.6 integration and
+ * other compatibility work.
+ */
+
+#ifndef SRE_RECURSIVE
+
+static char copyright[] =
+    " SRE 2.2.2 Copyright (c) 1997-2002 by Secret Labs AB ";
+
+#define PY_SSIZE_T_CLEAN
+
+#include "Python.h"
+#include "structmember.h" /* offsetof */
+
+#include "sre.h"
+
+#include <ctype.h>
+
+/* name of this module, minus the leading underscore */
+#if !defined(SRE_MODULE)
+#define SRE_MODULE "sre"
+#endif
+
+#define SRE_PY_MODULE "re"
+
+/* defining this one enables tracing */
+#undef VERBOSE
+
+#if PY_VERSION_HEX >= 0x01060000
+#if PY_VERSION_HEX  < 0x02020000 || defined(Py_USING_UNICODE)
+/* defining this enables unicode support (default under 1.6a1 and later) */
+#define HAVE_UNICODE
+#endif
+#endif
+
+/* -------------------------------------------------------------------- */
+/* optional features */
+
+/* enables fast searching */
+#define USE_FAST_SEARCH
+
+/* enables aggressive inlining (always on for Visual C) */
+#undef USE_INLINE
+
+/* enables copy/deepcopy handling (work in progress) */
+#undef USE_BUILTIN_COPY
+
+#if PY_VERSION_HEX < 0x01060000
+#define PyObject_DEL(op) PyMem_DEL((op))
+#endif
+
+/* -------------------------------------------------------------------- */
+
+#if defined(_MSC_VER)
+#pragma optimize("agtw", on) /* doesn't seem to make much difference... */
+#pragma warning(disable: 4710) /* who cares if functions are not inlined ;-) */
+/* fastest possible local call under MSVC */
+#define LOCAL(type) static __inline type __fastcall
+#elif defined(USE_INLINE)
+#define LOCAL(type) static inline type
+#else
+#define LOCAL(type) static type
+#endif
+
+/* error codes */
+#define SRE_ERROR_ILLEGAL -1 /* illegal opcode */
+#define SRE_ERROR_STATE -2 /* illegal state */
+#define SRE_ERROR_RECURSION_LIMIT -3 /* runaway recursion */
+#define SRE_ERROR_MEMORY -9 /* out of memory */
+#define SRE_ERROR_INTERRUPTED -10 /* signal handler raised exception */
+
+#if defined(VERBOSE)
+#define TRACE(v) printf v
+#else
+#define TRACE(v)
+#endif
+
+/* -------------------------------------------------------------------- */
+/* search engine state */
+
+/* default character predicates (run sre_chars.py to regenerate tables) */
+
+#define SRE_DIGIT_MASK 1
+#define SRE_SPACE_MASK 2
+#define SRE_LINEBREAK_MASK 4
+#define SRE_ALNUM_MASK 8
+#define SRE_WORD_MASK 16
+
+/* FIXME: this assumes ASCII.  create tables in init_sre() instead */
+
+static char sre_char_info[128] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 6, 2,
+2, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0,
+0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 25, 25, 25, 25, 25, 25, 25, 25,
+25, 25, 0, 0, 0, 0, 0, 0, 0, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
+24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 0, 0,
+0, 0, 16, 0, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
+24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 0, 0, 0, 0, 0 };
+
+static char sre_char_lower[128] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
+10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26,
+27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43,
+44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60,
+61, 62, 63, 64, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107,
+108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121,
+122, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105,
+106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119,
+120, 121, 122, 123, 124, 125, 126, 127 };
+
+#define SRE_IS_DIGIT(ch)\
+    ((ch) < 128 ? (sre_char_info[(ch)] & SRE_DIGIT_MASK) : 0)
+#define SRE_IS_SPACE(ch)\
+    ((ch) < 128 ? (sre_char_info[(ch)] & SRE_SPACE_MASK) : 0)
+#define SRE_IS_LINEBREAK(ch)\
+    ((ch) < 128 ? (sre_char_info[(ch)] & SRE_LINEBREAK_MASK) : 0)
+#define SRE_IS_ALNUM(ch)\
+    ((ch) < 128 ? (sre_char_info[(ch)] & SRE_ALNUM_MASK) : 0)
+#define SRE_IS_WORD(ch)\
+    ((ch) < 128 ? (sre_char_info[(ch)] & SRE_WORD_MASK) : 0)
+
+static unsigned int sre_lower(unsigned int ch)
+{
+    return ((ch) < 128 ? (unsigned int)sre_char_lower[ch] : ch);
+}
+
+/* locale-specific character predicates */
+/* !(c & ~N) == (c < N+1) for any unsigned c, this avoids
+ * warnings when c's type supports only numbers < N+1 */
+#define SRE_LOC_IS_DIGIT(ch) (!((ch) & ~255) ? isdigit((ch)) : 0)
+#define SRE_LOC_IS_SPACE(ch) (!((ch) & ~255) ? isspace((ch)) : 0)
+#define SRE_LOC_IS_LINEBREAK(ch) ((ch) == '\n')
+#define SRE_LOC_IS_ALNUM(ch) (!((ch) & ~255) ? isalnum((ch)) : 0)
+#define SRE_LOC_IS_WORD(ch) (SRE_LOC_IS_ALNUM((ch)) || (ch) == '_')
+
+static unsigned int sre_lower_locale(unsigned int ch)
+{
+    return ((ch) < 256 ? (unsigned int)tolower((ch)) : ch);
+}
+
+/* unicode-specific character predicates */
+
+#if defined(HAVE_UNICODE)
+
+#define SRE_UNI_IS_DIGIT(ch) Py_UNICODE_ISDIGIT((Py_UNICODE)(ch))
+#define SRE_UNI_IS_SPACE(ch) Py_UNICODE_ISSPACE((Py_UNICODE)(ch))
+#define SRE_UNI_IS_LINEBREAK(ch) Py_UNICODE_ISLINEBREAK((Py_UNICODE)(ch))
+#define SRE_UNI_IS_ALNUM(ch) Py_UNICODE_ISALNUM((Py_UNICODE)(ch))
+#define SRE_UNI_IS_WORD(ch) (SRE_UNI_IS_ALNUM((ch)) || (ch) == '_')
+
+static unsigned int sre_lower_unicode(unsigned int ch)
+{
+    return (unsigned int) Py_UNICODE_TOLOWER((Py_UNICODE)(ch));
+}
+
+#endif
+
+LOCAL(int)
+sre_category(SRE_CODE category, unsigned int ch)
+{
+    switch (category) {
+
+    case SRE_CATEGORY_DIGIT:
+        return SRE_IS_DIGIT(ch);
+    case SRE_CATEGORY_NOT_DIGIT:
+        return !SRE_IS_DIGIT(ch);
+    case SRE_CATEGORY_SPACE:
+        return SRE_IS_SPACE(ch);
+    case SRE_CATEGORY_NOT_SPACE:
+        return !SRE_IS_SPACE(ch);
+    case SRE_CATEGORY_WORD:
+        return SRE_IS_WORD(ch);
+    case SRE_CATEGORY_NOT_WORD:
+        return !SRE_IS_WORD(ch);
+    case SRE_CATEGORY_LINEBREAK:
+        return SRE_IS_LINEBREAK(ch);
+    case SRE_CATEGORY_NOT_LINEBREAK:
+        return !SRE_IS_LINEBREAK(ch);
+
+    case SRE_CATEGORY_LOC_WORD:
+        return SRE_LOC_IS_WORD(ch);
+    case SRE_CATEGORY_LOC_NOT_WORD:
+        return !SRE_LOC_IS_WORD(ch);
+
+#if defined(HAVE_UNICODE)
+    case SRE_CATEGORY_UNI_DIGIT:
+        return SRE_UNI_IS_DIGIT(ch);
+    case SRE_CATEGORY_UNI_NOT_DIGIT:
+        return !SRE_UNI_IS_DIGIT(ch);
+    case SRE_CATEGORY_UNI_SPACE:
+        return SRE_UNI_IS_SPACE(ch);
+    case SRE_CATEGORY_UNI_NOT_SPACE:
+        return !SRE_UNI_IS_SPACE(ch);
+    case SRE_CATEGORY_UNI_WORD:
+        return SRE_UNI_IS_WORD(ch);
+    case SRE_CATEGORY_UNI_NOT_WORD:
+        return !SRE_UNI_IS_WORD(ch);
+    case SRE_CATEGORY_UNI_LINEBREAK:
+        return SRE_UNI_IS_LINEBREAK(ch);
+    case SRE_CATEGORY_UNI_NOT_LINEBREAK:
+        return !SRE_UNI_IS_LINEBREAK(ch);
+#else
+    case SRE_CATEGORY_UNI_DIGIT:
+        return SRE_IS_DIGIT(ch);
+    case SRE_CATEGORY_UNI_NOT_DIGIT:
+        return !SRE_IS_DIGIT(ch);
+    case SRE_CATEGORY_UNI_SPACE:
+        return SRE_IS_SPACE(ch);
+    case SRE_CATEGORY_UNI_NOT_SPACE:
+        return !SRE_IS_SPACE(ch);
+    case SRE_CATEGORY_UNI_WORD:
+        return SRE_LOC_IS_WORD(ch);
+    case SRE_CATEGORY_UNI_NOT_WORD:
+        return !SRE_LOC_IS_WORD(ch);
+    case SRE_CATEGORY_UNI_LINEBREAK:
+        return SRE_IS_LINEBREAK(ch);
+    case SRE_CATEGORY_UNI_NOT_LINEBREAK:
+        return !SRE_IS_LINEBREAK(ch);
+#endif
+    }
+    return 0;
+}
+
+/* helpers */
+
+static void
+data_stack_dealloc(SRE_STATE* state)
+{
+    if (state->data_stack) {
+        PyMem_FREE(state->data_stack);
+        state->data_stack = NULL;
+    }
+    state->data_stack_size = state->data_stack_base = 0;
+}
+
+static int
+data_stack_grow(SRE_STATE* state, Py_ssize_t size)
+{
+    Py_ssize_t minsize, cursize;
+    minsize = state->data_stack_base+size;
+    cursize = state->data_stack_size;
+    if (cursize < minsize) {
+        void* stack;
+        cursize = minsize+minsize/4+1024;
+        TRACE(("allocate/grow stack %d\n", cursize));
+        stack = PyMem_REALLOC(state->data_stack, cursize);
+        if (!stack) {
+            data_stack_dealloc(state);
+            return SRE_ERROR_MEMORY;
+        }
+        state->data_stack = (char *)stack;
+        state->data_stack_size = cursize;
+    }
+    return 0;
+}
+
+/* generate 8-bit version */
+
+#define SRE_CHAR unsigned char
+#define SRE_AT sre_at
+#define SRE_COUNT sre_count
+#define SRE_CHARSET sre_charset
+#define SRE_INFO sre_info
+#define SRE_MATCH sre_match
+#define SRE_MATCH_CONTEXT sre_match_context
+#define SRE_SEARCH sre_search
+#define SRE_LITERAL_TEMPLATE sre_literal_template
+
+#if defined(HAVE_UNICODE)
+
+#define SRE_RECURSIVE
+#include "_sre.c"
+#undef SRE_RECURSIVE
+
+#undef SRE_LITERAL_TEMPLATE
+#undef SRE_SEARCH
+#undef SRE_MATCH
+#undef SRE_MATCH_CONTEXT
+#undef SRE_INFO
+#undef SRE_CHARSET
+#undef SRE_COUNT
+#undef SRE_AT
+#undef SRE_CHAR
+
+/* generate 16-bit unicode version */
+
+#define SRE_CHAR Py_UNICODE
+#define SRE_AT sre_uat
+#define SRE_COUNT sre_ucount
+#define SRE_CHARSET sre_ucharset
+#define SRE_INFO sre_uinfo
+#define SRE_MATCH sre_umatch
+#define SRE_MATCH_CONTEXT sre_umatch_context
+#define SRE_SEARCH sre_usearch
+#define SRE_LITERAL_TEMPLATE sre_uliteral_template
+#endif
+
+#endif /* SRE_RECURSIVE */
+
+/* -------------------------------------------------------------------- */
+/* String matching engine */
+
+/* the following section is compiled twice, with different character
+   settings */
+
+LOCAL(int)
+SRE_AT(SRE_STATE* state, SRE_CHAR* ptr, SRE_CODE at)
+{
+    /* check if pointer is at given position */
+
+    Py_ssize_t thisp, thatp;
+
+    switch (at) {
+
+    case SRE_AT_BEGINNING:
+    case SRE_AT_BEGINNING_STRING:
+        return ((void*) ptr == state->beginning);
+
+    case SRE_AT_BEGINNING_LINE:
+        return ((void*) ptr == state->beginning ||
+                SRE_IS_LINEBREAK((int) ptr[-1]));
+
+    case SRE_AT_END:
+        return (((void*) (ptr+1) == state->end &&
+                 SRE_IS_LINEBREAK((int) ptr[0])) ||
+                ((void*) ptr == state->end));
+
+    case SRE_AT_END_LINE:
+        return ((void*) ptr == state->end ||
+                SRE_IS_LINEBREAK((int) ptr[0]));
+
+    case SRE_AT_END_STRING:
+        return ((void*) ptr == state->end);
+
+    case SRE_AT_BOUNDARY:
+        if (state->beginning == state->end)
+            return 0;
+        thatp = ((void*) ptr > state->beginning) ?
+            SRE_IS_WORD((int) ptr[-1]) : 0;
+        thisp = ((void*) ptr < state->end) ?
+            SRE_IS_WORD((int) ptr[0]) : 0;
+        return thisp != thatp;
+
+    case SRE_AT_NON_BOUNDARY:
+        if (state->beginning == state->end)
+            return 0;
+        thatp = ((void*) ptr > state->beginning) ?
+            SRE_IS_WORD((int) ptr[-1]) : 0;
+        thisp = ((void*) ptr < state->end) ?
+            SRE_IS_WORD((int) ptr[0]) : 0;
+        return thisp == thatp;
+
+    case SRE_AT_LOC_BOUNDARY:
+        if (state->beginning == state->end)
+            return 0;
+        thatp = ((void*) ptr > state->beginning) ?
+            SRE_LOC_IS_WORD((int) ptr[-1]) : 0;
+        thisp = ((void*) ptr < state->end) ?
+            SRE_LOC_IS_WORD((int) ptr[0]) : 0;
+        return thisp != thatp;
+
+    case SRE_AT_LOC_NON_BOUNDARY:
+        if (state->beginning == state->end)
+            return 0;
+        thatp = ((void*) ptr > state->beginning) ?
+            SRE_LOC_IS_WORD((int) ptr[-1]) : 0;
+        thisp = ((void*) ptr < state->end) ?
+            SRE_LOC_IS_WORD((int) ptr[0]) : 0;
+        return thisp == thatp;
+
+#if defined(HAVE_UNICODE)
+    case SRE_AT_UNI_BOUNDARY:
+        if (state->beginning == state->end)
+            return 0;
+        thatp = ((void*) ptr > state->beginning) ?
+            SRE_UNI_IS_WORD((int) ptr[-1]) : 0;
+        thisp = ((void*) ptr < state->end) ?
+            SRE_UNI_IS_WORD((int) ptr[0]) : 0;
+        return thisp != thatp;
+
+    case SRE_AT_UNI_NON_BOUNDARY:
+        if (state->beginning == state->end)
+            return 0;
+        thatp = ((void*) ptr > state->beginning) ?
+            SRE_UNI_IS_WORD((int) ptr[-1]) : 0;
+        thisp = ((void*) ptr < state->end) ?
+            SRE_UNI_IS_WORD((int) ptr[0]) : 0;
+        return thisp == thatp;
+#endif
+
+    }
+
+    return 0;
+}
+
+LOCAL(int)
+SRE_CHARSET(SRE_CODE* set, SRE_CODE ch)
+{
+    /* check if character is a member of the given set */
+
+    int ok = 1;
+
+    for (;;) {
+        switch (*set++) {
+
+        case SRE_OP_FAILURE:
+            return !ok;
+
+        case SRE_OP_LITERAL:
+            /* <LITERAL> <code> */
+            if (ch == set[0])
+                return ok;
+            set++;
+            break;
+
+        case SRE_OP_CATEGORY:
+            /* <CATEGORY> <code> */
+            if (sre_category(set[0], (int) ch))
+                return ok;
+            set += 1;
+            break;
+
+        case SRE_OP_CHARSET:
+            if (sizeof(SRE_CODE) == 2) {
+                /* <CHARSET> <bitmap> (16 bits per code word) */
+                if (ch < 256 && (set[ch >> 4] & (1 << (ch & 15))))
+                    return ok;
+                set += 16;
+            }
+            else {
+                /* <CHARSET> <bitmap> (32 bits per code word) */
+                if (ch < 256 && (set[ch >> 5] & (1 << (ch & 31))))
+                    return ok;
+                set += 8;
+            }
+            break;
+
+        case SRE_OP_RANGE:
+            /* <RANGE> <lower> <upper> */
+            if (set[0] <= ch && ch <= set[1])
+                return ok;
+            set += 2;
+            break;
+
+        case SRE_OP_NEGATE:
+            ok = !ok;
+            break;
+
+        case SRE_OP_BIGCHARSET:
+            /* <BIGCHARSET> <blockcount> <256 blockindices> <blocks> */
+        {
+            Py_ssize_t count, block;
+            count = *(set++);
+
+            if (sizeof(SRE_CODE) == 2) {
+                block = ((unsigned char*)set)[ch >> 8];
+                set += 128;
+                if (set[block*16 + ((ch & 255)>>4)] & (1 << (ch & 15)))
+                    return ok;
+                set += count*16;
+            }
+            else {
+                /* !(c & ~N) == (c < N+1) for any unsigned c, this avoids
+                 * warnings when c's type supports only numbers < N+1 */
+                if (!(ch & ~65535))
+                    block = ((unsigned char*)set)[ch >> 8];
+                else
+                    block = -1;
+                set += 64;
+                if (block >=0 &&
+                    (set[block*8 + ((ch & 255)>>5)] & (1 << (ch & 31))))
+                    return ok;
+                set += count*8;
+            }
+            break;
+        }
+
+        default:
+            /* internal error -- there's not much we can do about it
+               here, so let's just pretend it didn't match... */
+            return 0;
+        }
+    }
+}
+
+LOCAL(Py_ssize_t) SRE_MATCH(SRE_STATE* state, SRE_CODE* pattern);
+
+LOCAL(Py_ssize_t)
+SRE_COUNT(SRE_STATE* state, SRE_CODE* pattern, Py_ssize_t maxcount)
+{
+    SRE_CODE chr;
+    SRE_CHAR* ptr = (SRE_CHAR *)state->ptr;
+    SRE_CHAR* end = (SRE_CHAR *)state->end;
+    Py_ssize_t i;
+
+    /* adjust end */
+    if (maxcount < end - ptr && maxcount != 65535)
+        end = ptr + maxcount;
+
+    switch (pattern[0]) {
+
+    case SRE_OP_IN:
+        /* repeated set */
+        TRACE(("|%p|%p|COUNT IN\n", pattern, ptr));
+        while (ptr < end && SRE_CHARSET(pattern + 2, *ptr))
+            ptr++;
+        break;
+
+    case SRE_OP_ANY:
+        /* repeated dot wildcard. */
+        TRACE(("|%p|%p|COUNT ANY\n", pattern, ptr));
+        while (ptr < end && !SRE_IS_LINEBREAK(*ptr))
+            ptr++;
+        break;
+
+    case SRE_OP_ANY_ALL:
+        /* repeated dot wildcard.  skip to the end of the target
+           string, and backtrack from there */
+        TRACE(("|%p|%p|COUNT ANY_ALL\n", pattern, ptr));
+        ptr = end;
+        break;
+
+    case SRE_OP_LITERAL:
+        /* repeated literal */
+        chr = pattern[1];
+        TRACE(("|%p|%p|COUNT LITERAL %d\n", pattern, ptr, chr));
+        while (ptr < end && (SRE_CODE) *ptr == chr)
+            ptr++;
+        break;
+
+    case SRE_OP_LITERAL_IGNORE:
+        /* repeated literal */
+        chr = pattern[1];
+        TRACE(("|%p|%p|COUNT LITERAL_IGNORE %d\n", pattern, ptr, chr));
+        while (ptr < end && (SRE_CODE) state->lower(*ptr) == chr)
+            ptr++;
+        break;
+
+    case SRE_OP_NOT_LITERAL:
+        /* repeated non-literal */
+        chr = pattern[1];
+        TRACE(("|%p|%p|COUNT NOT_LITERAL %d\n", pattern, ptr, chr));
+        while (ptr < end && (SRE_CODE) *ptr != chr)
+            ptr++;
+        break;
+
+    case SRE_OP_NOT_LITERAL_IGNORE:
+        /* repeated non-literal */
+        chr = pattern[1];
+        TRACE(("|%p|%p|COUNT NOT_LITERAL_IGNORE %d\n", pattern, ptr, chr));
+        while (ptr < end && (SRE_CODE) state->lower(*ptr) != chr)
+            ptr++;
+        break;
+
+    default:
+        /* repeated single character pattern */
+        TRACE(("|%p|%p|COUNT SUBPATTERN\n", pattern, ptr));
+        while ((SRE_CHAR*) state->ptr < end) {
+            i = SRE_MATCH(state, pattern);
+            if (i < 0)
+                return i;
+            if (!i)
+                break;
+        }
+        TRACE(("|%p|%p|COUNT %d\n", pattern, ptr,
+               (SRE_CHAR*) state->ptr - ptr));
+        return (SRE_CHAR*) state->ptr - ptr;
+    }
+
+    TRACE(("|%p|%p|COUNT %d\n", pattern, ptr, ptr - (SRE_CHAR*) state->ptr));
+    return ptr - (SRE_CHAR*) state->ptr;
+}
+
+#if 0 /* not used in this release */
+LOCAL(int)
+SRE_INFO(SRE_STATE* state, SRE_CODE* pattern)
+{
+    /* check if an SRE_OP_INFO block matches at the current position.
+       returns the number of SRE_CODE objects to skip if successful, 0
+       if no match */
+
+    SRE_CHAR* end = state->end;
+    SRE_CHAR* ptr = state->ptr;
+    Py_ssize_t i;
+
+    /* check minimal length */
+    if (pattern[3] && (end - ptr) < pattern[3])
+        return 0;
+
+    /* check known prefix */
+    if (pattern[2] & SRE_INFO_PREFIX && pattern[5] > 1) {
+        /* <length> <skip> <prefix data> <overlap data> */
+        for (i = 0; i < pattern[5]; i++)
+            if ((SRE_CODE) ptr[i] != pattern[7 + i])
+                return 0;
+        return pattern[0] + 2 * pattern[6];
+    }
+    return pattern[0];
+}
+#endif
+
+/* The macros below should be used to protect recursive SRE_MATCH()
+ * calls that *failed* and do *not* return immediately (IOW, those
+ * that will backtrack). Explaining:
+ *
+ * - Recursive SRE_MATCH() returned true: that's usually a success
+ *   (besides atypical cases like ASSERT_NOT), therefore there's no
+ *   reason to restore lastmark;
+ *
+ * - Recursive SRE_MATCH() returned false but the current SRE_MATCH()
+ *   is returning to the caller: If the current SRE_MATCH() is the
+ *   top function of the recursion, returning false will be a matching
+ *   failure, and it doesn't matter where lastmark is pointing to.
+ *   If it's *not* the top function, it will be a recursive SRE_MATCH()
+ *   failure by itself, and the calling SRE_MATCH() will have to deal
+ *   with the failure by the same rules explained here (it will restore
+ *   lastmark by itself if necessary);
+ *
+ * - Recursive SRE_MATCH() returned false, and will continue the
+ *   outside 'for' loop: must be protected when breaking, since the next
+ *   OP could potentially depend on lastmark;
+ *
+ * - Recursive SRE_MATCH() returned false, and will be called again
+ *   inside a local for/while loop: must be protected between each
+ *   loop iteration, since the recursive SRE_MATCH() could do anything,
+ *   and could potentially depend on lastmark.
+ *
+ * For more information, check the discussion at SF patch #712900.
+ */
+#define LASTMARK_SAVE()     \
+    do { \
+        ctx->lastmark = state->lastmark; \
+        ctx->lastindex = state->lastindex; \
+    } while (0)
+#define LASTMARK_RESTORE()  \
+    do { \
+        state->lastmark = ctx->lastmark; \
+        state->lastindex = ctx->lastindex; \
+    } while (0)
+
+#define RETURN_ERROR(i) do { return i; } while(0)
+#define RETURN_FAILURE do { ret = 0; goto exit; } while(0)
+#define RETURN_SUCCESS do { ret = 1; goto exit; } while(0)
+
+#define RETURN_ON_ERROR(i) \
+    do { if (i < 0) RETURN_ERROR(i); } while (0)
+#define RETURN_ON_SUCCESS(i) \
+    do { RETURN_ON_ERROR(i); if (i > 0) RETURN_SUCCESS; } while (0)
+#define RETURN_ON_FAILURE(i) \
+    do { RETURN_ON_ERROR(i); if (i == 0) RETURN_FAILURE; } while (0)
+
+#define SFY(x) #x
+
+#define DATA_STACK_ALLOC(state, type, ptr) \
+do { \
+    alloc_pos = state->data_stack_base; \
+    TRACE(("allocating %s in %d (%d)\n", \
+           SFY(type), alloc_pos, sizeof(type))); \
+    if (state->data_stack_size < alloc_pos+sizeof(type)) { \
+        int j = data_stack_grow(state, sizeof(type)); \
+        if (j < 0) return j; \
+        if (ctx_pos != -1) \
+            DATA_STACK_LOOKUP_AT(state, SRE_MATCH_CONTEXT, ctx, ctx_pos); \
+    } \
+    ptr = (type*)(state->data_stack+alloc_pos); \
+    state->data_stack_base += sizeof(type); \
+} while (0)
+
+#define DATA_STACK_LOOKUP_AT(state, type, ptr, pos) \
+do { \
+    TRACE(("looking up %s at %d\n", SFY(type), pos)); \
+    ptr = (type*)(state->data_stack+pos); \
+} while (0)
+
+#define DATA_STACK_PUSH(state, data, size) \
+do { \
+    TRACE(("copy data in %p to %d (%d)\n", \
+           data, state->data_stack_base, size)); \
+    if (state->data_stack_size < state->data_stack_base+size) { \
+        int j = data_stack_grow(state, size); \
+        if (j < 0) return j; \
+        if (ctx_pos != -1) \
+            DATA_STACK_LOOKUP_AT(state, SRE_MATCH_CONTEXT, ctx, ctx_pos); \
+    } \
+    memcpy(state->data_stack+state->data_stack_base, data, size); \
+    state->data_stack_base += size; \
+} while (0)
+
+#define DATA_STACK_POP(state, data, size, discard) \
+do { \
+    TRACE(("copy data to %p from %d (%d)\n", \
+           data, state->data_stack_base-size, size)); \
+    memcpy(data, state->data_stack+state->data_stack_base-size, size); \
+    if (discard) \
+        state->data_stack_base -= size; \
+} while (0)
+
+#define DATA_STACK_POP_DISCARD(state, size) \
+do { \
+    TRACE(("discard data from %d (%d)\n", \
+           state->data_stack_base-size, size)); \
+    state->data_stack_base -= size; \
+} while(0)
+
+#define DATA_PUSH(x) \
+    DATA_STACK_PUSH(state, (x), sizeof(*(x)))
+#define DATA_POP(x) \
+    DATA_STACK_POP(state, (x), sizeof(*(x)), 1)
+#define DATA_POP_DISCARD(x) \
+    DATA_STACK_POP_DISCARD(state, sizeof(*(x)))
+#define DATA_ALLOC(t,p) \
+    DATA_STACK_ALLOC(state, t, p)
+#define DATA_LOOKUP_AT(t,p,pos) \
+    DATA_STACK_LOOKUP_AT(state,t,p,pos)
+
+#define MARK_PUSH(lastmark) \
+    do if (lastmark > 0) { \
+        i = lastmark; /* ctx->lastmark may change if reallocated */ \
+        DATA_STACK_PUSH(state, state->mark, (i+1)*sizeof(void*)); \
+    } while (0)
+#define MARK_POP(lastmark) \
+    do if (lastmark > 0) { \
+        DATA_STACK_POP(state, state->mark, (lastmark+1)*sizeof(void*), 1); \
+    } while (0)
+#define MARK_POP_KEEP(lastmark) \
+    do if (lastmark > 0) { \
+        DATA_STACK_POP(state, state->mark, (lastmark+1)*sizeof(void*), 0); \
+    } while (0)
+#define MARK_POP_DISCARD(lastmark) \
+    do if (lastmark > 0) { \
+        DATA_STACK_POP_DISCARD(state, (lastmark+1)*sizeof(void*)); \
+    } while (0)
+
+#define JUMP_NONE            0
+#define JUMP_MAX_UNTIL_1     1
+#define JUMP_MAX_UNTIL_2     2
+#define JUMP_MAX_UNTIL_3     3
+#define JUMP_MIN_UNTIL_1     4
+#define JUMP_MIN_UNTIL_2     5
+#define JUMP_MIN_UNTIL_3     6
+#define JUMP_REPEAT          7
+#define JUMP_REPEAT_ONE_1    8
+#define JUMP_REPEAT_ONE_2    9
+#define JUMP_MIN_REPEAT_ONE  10
+#define JUMP_BRANCH          11
+#define JUMP_ASSERT          12
+#define JUMP_ASSERT_NOT      13
+
+#define DO_JUMP(jumpvalue, jumplabel, nextpattern) \
+    DATA_ALLOC(SRE_MATCH_CONTEXT, nextctx); \
+    nextctx->last_ctx_pos = ctx_pos; \
+    nextctx->jump = jumpvalue; \
+    nextctx->pattern = nextpattern; \
+    ctx_pos = alloc_pos; \
+    ctx = nextctx; \
+    goto entrance; \
+    jumplabel: \
+    while (0) /* gcc doesn't like labels at end of scopes */ \
+
+typedef struct {
+    Py_ssize_t last_ctx_pos;
+    Py_ssize_t jump;
+    SRE_CHAR* ptr;
+    SRE_CODE* pattern;
+    Py_ssize_t count;
+    Py_ssize_t lastmark;
+    Py_ssize_t lastindex;
+    union {
+        SRE_CODE chr;
+        SRE_REPEAT* rep;
+    } u;
+} SRE_MATCH_CONTEXT;
+
+/* check if string matches the given pattern.  returns <0 for
+   error, 0 for failure, and 1 for success */
+LOCAL(Py_ssize_t)
+SRE_MATCH(SRE_STATE* state, SRE_CODE* pattern)
+{
+    SRE_CHAR* end = (SRE_CHAR *)state->end;
+    Py_ssize_t alloc_pos, ctx_pos = -1;
+    Py_ssize_t i, ret = 0;
+    Py_ssize_t jump;
+    unsigned int sigcount=0;
+
+    SRE_MATCH_CONTEXT* ctx;
+    SRE_MATCH_CONTEXT* nextctx;
+
+    TRACE(("|%p|%p|ENTER\n", pattern, state->ptr));
+
+    DATA_ALLOC(SRE_MATCH_CONTEXT, ctx);
+    ctx->last_ctx_pos = -1;
+    ctx->jump = JUMP_NONE;
+    ctx->pattern = pattern;
+    ctx_pos = alloc_pos;
+
+entrance:
+
+    ctx->ptr = (SRE_CHAR *)state->ptr;
+
+    if (ctx->pattern[0] == SRE_OP_INFO) {
+        /* optimization info block */
+        /* <INFO> <1=skip> <2=flags> <3=min> ... */
+        if (ctx->pattern[3] && (end - ctx->ptr) < ctx->pattern[3]) {
+            TRACE(("reject (got %d chars, need %d)\n",
+                   (end - ctx->ptr), ctx->pattern[3]));
+            RETURN_FAILURE;
+        }
+        ctx->pattern += ctx->pattern[1] + 1;
+    }
+
+    for (;;) {
+        ++sigcount;
+        if ((0 == (sigcount & 0xfff)) && PyErr_CheckSignals())
+            RETURN_ERROR(SRE_ERROR_INTERRUPTED);
+
+        switch (*ctx->pattern++) {
+
+        case SRE_OP_MARK:
+            /* set mark */
+            /* <MARK> <gid> */
+            TRACE(("|%p|%p|MARK %d\n", ctx->pattern,
+                   ctx->ptr, ctx->pattern[0]));
+            i = ctx->pattern[0];
+            if (i & 1)
+                state->lastindex = i/2 + 1;
+            if (i > state->lastmark) {
+                /* state->lastmark is the highest valid index in the
+                   state->mark array.  If it is increased by more than 1,
+                   the intervening marks must be set to NULL to signal
+                   that these marks have not been encountered. */
+                Py_ssize_t j = state->lastmark + 1;
+                while (j < i)
+                    state->mark[j++] = NULL;
+                state->lastmark = i;
+            }
+            state->mark[i] = ctx->ptr;
+            ctx->pattern++;
+            break;
+
+        case SRE_OP_LITERAL:
+            /* match literal string */
+            /* <LITERAL> <code> */
+            TRACE(("|%p|%p|LITERAL %d\n", ctx->pattern,
+                   ctx->ptr, *ctx->pattern));
+            if (ctx->ptr >= end || (SRE_CODE) ctx->ptr[0] != ctx->pattern[0])
+                RETURN_FAILURE;
+            ctx->pattern++;
+            ctx->ptr++;
+            break;
+
+        case SRE_OP_NOT_LITERAL:
+            /* match anything that is not literal character */
+            /* <NOT_LITERAL> <code> */
+            TRACE(("|%p|%p|NOT_LITERAL %d\n", ctx->pattern,
+                   ctx->ptr, *ctx->pattern));
+            if (ctx->ptr >= end || (SRE_CODE) ctx->ptr[0] == ctx->pattern[0])
+                RETURN_FAILURE;
+            ctx->pattern++;
+            ctx->ptr++;
+            break;
+
+        case SRE_OP_SUCCESS:
+            /* end of pattern */
+            TRACE(("|%p|%p|SUCCESS\n", ctx->pattern, ctx->ptr));
+            state->ptr = ctx->ptr;
+            RETURN_SUCCESS;
+
+        case SRE_OP_AT:
+            /* match at given position */
+            /* <AT> <code> */
+            TRACE(("|%p|%p|AT %d\n", ctx->pattern, ctx->ptr, *ctx->pattern));
+            if (!SRE_AT(state, ctx->ptr, *ctx->pattern))
+                RETURN_FAILURE;
+            ctx->pattern++;
+            break;
+
+        case SRE_OP_CATEGORY:
+            /* match at given category */
+            /* <CATEGORY> <code> */
+            TRACE(("|%p|%p|CATEGORY %d\n", ctx->pattern,
+                   ctx->ptr, *ctx->pattern));
+            if (ctx->ptr >= end || !sre_category(ctx->pattern[0], ctx->ptr[0]))
+                RETURN_FAILURE;
+            ctx->pattern++;
+            ctx->ptr++;
+            break;
+
+        case SRE_OP_ANY:
+            /* match anything (except a newline) */
+            /* <ANY> */
+            TRACE(("|%p|%p|ANY\n", ctx->pattern, ctx->ptr));
+            if (ctx->ptr >= end || SRE_IS_LINEBREAK(ctx->ptr[0]))
+                RETURN_FAILURE;
+            ctx->ptr++;
+            break;
+
+        case SRE_OP_ANY_ALL:
+            /* match anything */
+            /* <ANY_ALL> */
+            TRACE(("|%p|%p|ANY_ALL\n", ctx->pattern, ctx->ptr));
+            if (ctx->ptr >= end)
+                RETURN_FAILURE;
+            ctx->ptr++;
+            break;
+
+        case SRE_OP_IN:
+            /* match set member (or non_member) */
+            /* <IN> <skip> <set> */
+            TRACE(("|%p|%p|IN\n", ctx->pattern, ctx->ptr));
+            if (ctx->ptr >= end || !SRE_CHARSET(ctx->pattern + 1, *ctx->ptr))
+                RETURN_FAILURE;
+            ctx->pattern += ctx->pattern[0];
+            ctx->ptr++;
+            break;
+
+        case SRE_OP_LITERAL_IGNORE:
+            TRACE(("|%p|%p|LITERAL_IGNORE %d\n",
+                   ctx->pattern, ctx->ptr, ctx->pattern[0]));
+            if (ctx->ptr >= end ||
+                state->lower(*ctx->ptr) != state->lower(*ctx->pattern))
+                RETURN_FAILURE;
+            ctx->pattern++;
+            ctx->ptr++;
+            break;
+
+        case SRE_OP_NOT_LITERAL_IGNORE:
+            TRACE(("|%p|%p|NOT_LITERAL_IGNORE %d\n",
+                   ctx->pattern, ctx->ptr, *ctx->pattern));
+            if (ctx->ptr >= end ||
+                state->lower(*ctx->ptr) == state->lower(*ctx->pattern))
+                RETURN_FAILURE;
+            ctx->pattern++;
+            ctx->ptr++;
+            break;
+
+        case SRE_OP_IN_IGNORE:
+            TRACE(("|%p|%p|IN_IGNORE\n", ctx->pattern, ctx->ptr));
+            if (ctx->ptr >= end
+                || !SRE_CHARSET(ctx->pattern+1,
+                                (SRE_CODE)state->lower(*ctx->ptr)))
+                RETURN_FAILURE;
+            ctx->pattern += ctx->pattern[0];
+            ctx->ptr++;
+            break;
+
+        case SRE_OP_JUMP:
+        case SRE_OP_INFO:
+            /* jump forward */
+            /* <JUMP> <offset> */
+            TRACE(("|%p|%p|JUMP %d\n", ctx->pattern,
+                   ctx->ptr, ctx->pattern[0]));
+            ctx->pattern += ctx->pattern[0];
+            break;
+
+        case SRE_OP_BRANCH:
+            /* alternation */
+            /* <BRANCH> <0=skip> code <JUMP> ... <NULL> */
+            TRACE(("|%p|%p|BRANCH\n", ctx->pattern, ctx->ptr));
+            LASTMARK_SAVE();
+            ctx->u.rep = state->repeat;
+            if (ctx->u.rep)
+                MARK_PUSH(ctx->lastmark);
+            for (; ctx->pattern[0]; ctx->pattern += ctx->pattern[0]) {
+                if (ctx->pattern[1] == SRE_OP_LITERAL &&
+                    (ctx->ptr >= end ||
+                     (SRE_CODE) *ctx->ptr != ctx->pattern[2]))
+                    continue;
+                if (ctx->pattern[1] == SRE_OP_IN &&
+                    (ctx->ptr >= end ||
+                     !SRE_CHARSET(ctx->pattern + 3, (SRE_CODE) *ctx->ptr)))
+                    continue;
+                state->ptr = ctx->ptr;
+                DO_JUMP(JUMP_BRANCH, jump_branch, ctx->pattern+1);
+                if (ret) {
+                    if (ctx->u.rep)
+                        MARK_POP_DISCARD(ctx->lastmark);
+                    RETURN_ON_ERROR(ret);
+                    RETURN_SUCCESS;
+                }
+                if (ctx->u.rep)
+                    MARK_POP_KEEP(ctx->lastmark);
+                LASTMARK_RESTORE();
+            }
+            if (ctx->u.rep)
+                MARK_POP_DISCARD(ctx->lastmark);
+            RETURN_FAILURE;
+
+        case SRE_OP_REPEAT_ONE:
+            /* match repeated sequence (maximizing regexp) */
+
+            /* this operator only works if the repeated item is
+               exactly one character wide, and we're not already
+               collecting backtracking points.  for other cases,
+               use the MAX_REPEAT operator */
+
+            /* <REPEAT_ONE> <skip> <1=min> <2=max> item <SUCCESS> tail */
+
+            TRACE(("|%p|%p|REPEAT_ONE %d %d\n", ctx->pattern, ctx->ptr,
+                   ctx->pattern[1], ctx->pattern[2]));
+
+            if (ctx->ptr + ctx->pattern[1] > end)
+                RETURN_FAILURE; /* cannot match */
+
+            state->ptr = ctx->ptr;
+
+            ret = SRE_COUNT(state, ctx->pattern+3, ctx->pattern[2]);
+            RETURN_ON_ERROR(ret);
+            DATA_LOOKUP_AT(SRE_MATCH_CONTEXT, ctx, ctx_pos);
+            ctx->count = ret;
+            ctx->ptr += ctx->count;
+
+            /* when we arrive here, count contains the number of
+               matches, and ctx->ptr points to the tail of the target
+               string.  check if the rest of the pattern matches,
+               and backtrack if not. */
+
+            if (ctx->count < (Py_ssize_t) ctx->pattern[1])
+                RETURN_FAILURE;
+
+            if (ctx->pattern[ctx->pattern[0]] == SRE_OP_SUCCESS) {
+                /* tail is empty.  we're finished */
+                state->ptr = ctx->ptr;
+                RETURN_SUCCESS;
+            }
+
+            LASTMARK_SAVE();
+
+            if (ctx->pattern[ctx->pattern[0]] == SRE_OP_LITERAL) {
+                /* tail starts with a literal. skip positions where
+                   the rest of the pattern cannot possibly match */
+                ctx->u.chr = ctx->pattern[ctx->pattern[0]+1];
+                for (;;) {
+                    while (ctx->count >= (Py_ssize_t) ctx->pattern[1] &&
+                           (ctx->ptr >= end || *ctx->ptr != ctx->u.chr)) {
+                        ctx->ptr--;
+                        ctx->count--;
+                    }
+                    if (ctx->count < (Py_ssize_t) ctx->pattern[1])
+                        break;
+                    state->ptr = ctx->ptr;
+                    DO_JUMP(JUMP_REPEAT_ONE_1, jump_repeat_one_1,
+                            ctx->pattern+ctx->pattern[0]);
+                    if (ret) {
+                        RETURN_ON_ERROR(ret);
+                        RETURN_SUCCESS;
+                    }
+
+                    LASTMARK_RESTORE();
+
+                    ctx->ptr--;
+                    ctx->count--;
+                }
+
+            } else {
+                /* general case */
+                while (ctx->count >= (Py_ssize_t) ctx->pattern[1]) {
+                    state->ptr = ctx->ptr;
+                    DO_JUMP(JUMP_REPEAT_ONE_2, jump_repeat_one_2,
+                            ctx->pattern+ctx->pattern[0]);
+                    if (ret) {
+                        RETURN_ON_ERROR(ret);
+                        RETURN_SUCCESS;
+                    }
+                    ctx->ptr--;
+                    ctx->count--;
+                    LASTMARK_RESTORE();
+                }
+            }
+            RETURN_FAILURE;
+
+        case SRE_OP_MIN_REPEAT_ONE:
+            /* match repeated sequence (minimizing regexp) */
+
+            /* this operator only works if the repeated item is
+               exactly one character wide, and we're not already
+               collecting backtracking points.  for other cases,
+               use the MIN_REPEAT operator */
+
+            /* <MIN_REPEAT_ONE> <skip> <1=min> <2=max> item <SUCCESS> tail */
+
+            TRACE(("|%p|%p|MIN_REPEAT_ONE %d %d\n", ctx->pattern, ctx->ptr,
+                   ctx->pattern[1], ctx->pattern[2]));
+
+            if (ctx->ptr + ctx->pattern[1] > end)
+                RETURN_FAILURE; /* cannot match */
+
+            state->ptr = ctx->ptr;
+
+            if (ctx->pattern[1] == 0)
+                ctx->count = 0;
+            else {
+                /* count using pattern min as the maximum */
+                ret = SRE_COUNT(state, ctx->pattern+3, ctx->pattern[1]);
+                RETURN_ON_ERROR(ret);
+                DATA_LOOKUP_AT(SRE_MATCH_CONTEXT, ctx, ctx_pos);
+                if (ret < (Py_ssize_t) ctx->pattern[1])
+                    /* didn't match minimum number of times */
+                    RETURN_FAILURE;
+                /* advance past minimum matches of repeat */
+                ctx->count = ret;
+                ctx->ptr += ctx->count;
+            }
+
+            if (ctx->pattern[ctx->pattern[0]] == SRE_OP_SUCCESS) {
+                /* tail is empty.  we're finished */
+                state->ptr = ctx->ptr;
+                RETURN_SUCCESS;
+
+            } else {
+                /* general case */
+                LASTMARK_SAVE();
+                while ((Py_ssize_t)ctx->pattern[2] == 65535
+                       || ctx->count <= (Py_ssize_t)ctx->pattern[2]) {
+                    state->ptr = ctx->ptr;
+                    DO_JUMP(JUMP_MIN_REPEAT_ONE,jump_min_repeat_one,
+                            ctx->pattern+ctx->pattern[0]);
+                    if (ret) {
+                        RETURN_ON_ERROR(ret);
+                        RETURN_SUCCESS;
+                    }
+                    state->ptr = ctx->ptr;
+                    ret = SRE_COUNT(state, ctx->pattern+3, 1);
+                    RETURN_ON_ERROR(ret);
+                    DATA_LOOKUP_AT(SRE_MATCH_CONTEXT, ctx, ctx_pos);
+                    if (ret == 0)
+                        break;
+                    assert(ret == 1);
+                    ctx->ptr++;
+                    ctx->count++;
+                    LASTMARK_RESTORE();
+                }
+            }
+            RETURN_FAILURE;
+
+        case SRE_OP_REPEAT:
+            /* create repeat context.  all the hard work is done
+               by the UNTIL operator (MAX_UNTIL, MIN_UNTIL) */
+            /* <REPEAT> <skip> <1=min> <2=max> item <UNTIL> tail */
+            TRACE(("|%p|%p|REPEAT %d %d\n", ctx->pattern, ctx->ptr,
+                   ctx->pattern[1], ctx->pattern[2]));
+
+            /* install new repeat context */
+            ctx->u.rep = (SRE_REPEAT*) PyObject_MALLOC(sizeof(*ctx->u.rep));
+            if (!ctx->u.rep) {
+                PyErr_NoMemory();
+                RETURN_FAILURE;
+            }
+            ctx->u.rep->count = -1;
+            ctx->u.rep->pattern = ctx->pattern;
+            ctx->u.rep->prev = state->repeat;
+            ctx->u.rep->last_ptr = NULL;
+            state->repeat = ctx->u.rep;
+
+            state->ptr = ctx->ptr;
+            DO_JUMP(JUMP_REPEAT, jump_repeat, ctx->pattern+ctx->pattern[0]);
+            state->repeat = ctx->u.rep->prev;
+            PyObject_FREE(ctx->u.rep);
+
+            if (ret) {
+                RETURN_ON_ERROR(ret);
+                RETURN_SUCCESS;
+            }
+            RETURN_FAILURE;
+
+        case SRE_OP_MAX_UNTIL:
+            /* maximizing repeat */
+            /* <REPEAT> <skip> <1=min> <2=max> item <MAX_UNTIL> tail */
+
+            /* FIXME: we probably need to deal with zero-width
+               matches in here... */
+
+            ctx->u.rep = state->repeat;
+            if (!ctx->u.rep)
+                RETURN_ERROR(SRE_ERROR_STATE);
+
+            state->ptr = ctx->ptr;
+
+            ctx->count = ctx->u.rep->count+1;
+
+            TRACE(("|%p|%p|MAX_UNTIL %d\n", ctx->pattern,
+                   ctx->ptr, ctx->count));
+
+            if (ctx->count < ctx->u.rep->pattern[1]) {
+                /* not enough matches */
+                ctx->u.rep->count = ctx->count;
+                DO_JUMP(JUMP_MAX_UNTIL_1, jump_max_until_1,
+                        ctx->u.rep->pattern+3);
+                if (ret) {
+                    RETURN_ON_ERROR(ret);
+                    RETURN_SUCCESS;
+                }
+                ctx->u.rep->count = ctx->count-1;
+                state->ptr = ctx->ptr;
+                RETURN_FAILURE;
+            }
+
+            if ((ctx->count < ctx->u.rep->pattern[2] ||
+                ctx->u.rep->pattern[2] == 65535) &&
+                state->ptr != ctx->u.rep->last_ptr) {
+                /* we may have enough matches, but if we can
+                   match another item, do so */
+                ctx->u.rep->count = ctx->count;
+                LASTMARK_SAVE();
+                MARK_PUSH(ctx->lastmark);
+                /* zero-width match protection */
+                DATA_PUSH(&ctx->u.rep->last_ptr);
+                ctx->u.rep->last_ptr = state->ptr;
+                DO_JUMP(JUMP_MAX_UNTIL_2, jump_max_until_2,
+                        ctx->u.rep->pattern+3);
+                DATA_POP(&ctx->u.rep->last_ptr);
+                if (ret) {
+                    MARK_POP_DISCARD(ctx->lastmark);
+                    RETURN_ON_ERROR(ret);
+                    RETURN_SUCCESS;
+                }
+                MARK_POP(ctx->lastmark);
+                LASTMARK_RESTORE();
+                ctx->u.rep->count = ctx->count-1;
+                state->ptr = ctx->ptr;
+            }
+
+            /* cannot match more repeated items here.  make sure the
+               tail matches */
+            state->repeat = ctx->u.rep->prev;
+            DO_JUMP(JUMP_MAX_UNTIL_3, jump_max_until_3, ctx->pattern);
+            RETURN_ON_SUCCESS(ret);
+            state->repeat = ctx->u.rep;
+            state->ptr = ctx->ptr;
+            RETURN_FAILURE;
+
+        case SRE_OP_MIN_UNTIL:
+            /* minimizing repeat */
+            /* <REPEAT> <skip> <1=min> <2=max> item <MIN_UNTIL> tail */
+
+            ctx->u.rep = state->repeat;
+            if (!ctx->u.rep)
+                RETURN_ERROR(SRE_ERROR_STATE);
+
+            state->ptr = ctx->ptr;
+
+            ctx->count = ctx->u.rep->count+1;
+
+            TRACE(("|%p|%p|MIN_UNTIL %d %p\n", ctx->pattern,
+                   ctx->ptr, ctx->count, ctx->u.rep->pattern));
+
+            if (ctx->count < ctx->u.rep->pattern[1]) {
+                /* not enough matches */
+                ctx->u.rep->count = ctx->count;
+                DO_JUMP(JUMP_MIN_UNTIL_1, jump_min_until_1,
+                        ctx->u.rep->pattern+3);
+                if (ret) {
+                    RETURN_ON_ERROR(ret);
+                    RETURN_SUCCESS;
+                }
+                ctx->u.rep->count = ctx->count-1;
+                state->ptr = ctx->ptr;
+                RETURN_FAILURE;
+            }
+
+            LASTMARK_SAVE();
+
+            /* see if the tail matches */
+            state->repeat = ctx->u.rep->prev;
+            DO_JUMP(JUMP_MIN_UNTIL_2, jump_min_until_2, ctx->pattern);
+            if (ret) {
+                RETURN_ON_ERROR(ret);
+                RETURN_SUCCESS;
+            }
+
+            state->repeat = ctx->u.rep;
+            state->ptr = ctx->ptr;
+
+            LASTMARK_RESTORE();
+
+            if (ctx->count >= ctx->u.rep->pattern[2]
+                && ctx->u.rep->pattern[2] != 65535)
+                RETURN_FAILURE;
+
+            ctx->u.rep->count = ctx->count;
+            DO_JUMP(JUMP_MIN_UNTIL_3,jump_min_until_3,
+                    ctx->u.rep->pattern+3);
+            if (ret) {
+                RETURN_ON_ERROR(ret);
+                RETURN_SUCCESS;
+            }
+            ctx->u.rep->count = ctx->count-1;
+            state->ptr = ctx->ptr;
+            RETURN_FAILURE;
+
+        case SRE_OP_GROUPREF:
+            /* match backreference */
+            TRACE(("|%p|%p|GROUPREF %d\n", ctx->pattern,
+                   ctx->ptr, ctx->pattern[0]));
+            i = ctx->pattern[0];
+            {
+                Py_ssize_t groupref = i+i;
+                if (groupref >= state->lastmark) {
+                    RETURN_FAILURE;
+                } else {
+                    SRE_CHAR* p = (SRE_CHAR*) state->mark[groupref];
+                    SRE_CHAR* e = (SRE_CHAR*) state->mark[groupref+1];
+                    if (!p || !e || e < p)
+                        RETURN_FAILURE;
+                    while (p < e) {
+                        if (ctx->ptr >= end || *ctx->ptr != *p)
+                            RETURN_FAILURE;
+                        p++; ctx->ptr++;
+                    }
+                }
+            }
+            ctx->pattern++;
+            break;
+
+        case SRE_OP_GROUPREF_IGNORE:
+            /* match backreference */
+            TRACE(("|%p|%p|GROUPREF_IGNORE %d\n", ctx->pattern,
+                   ctx->ptr, ctx->pattern[0]));
+            i = ctx->pattern[0];
+            {
+                Py_ssize_t groupref = i+i;
+                if (groupref >= state->lastmark) {
+                    RETURN_FAILURE;
+                } else {
+                    SRE_CHAR* p = (SRE_CHAR*) state->mark[groupref];
+                    SRE_CHAR* e = (SRE_CHAR*) state->mark[groupref+1];
+                    if (!p || !e || e < p)
+                        RETURN_FAILURE;
+                    while (p < e) {
+                        if (ctx->ptr >= end ||
+                            state->lower(*ctx->ptr) != state->lower(*p))
+                            RETURN_FAILURE;
+                        p++; ctx->ptr++;
+                    }
+                }
+            }
+            ctx->pattern++;
+            break;
+
+        case SRE_OP_GROUPREF_EXISTS:
+            TRACE(("|%p|%p|GROUPREF_EXISTS %d\n", ctx->pattern,
+                   ctx->ptr, ctx->pattern[0]));
+            /* <GROUPREF_EXISTS> <group> <skip> codeyes <JUMP> codeno ... */
+            i = ctx->pattern[0];
+            {
+                Py_ssize_t groupref = i+i;
+                if (groupref >= state->lastmark) {
+                    ctx->pattern += ctx->pattern[1];
+                    break;
+                } else {
+                    SRE_CHAR* p = (SRE_CHAR*) state->mark[groupref];
+                    SRE_CHAR* e = (SRE_CHAR*) state->mark[groupref+1];
+                    if (!p || !e || e < p) {
+                        ctx->pattern += ctx->pattern[1];
+                        break;
+                    }
+                }
+            }
+            ctx->pattern += 2;
+            break;
+
+        case SRE_OP_ASSERT:
+            /* assert subpattern */
+            /* <ASSERT> <skip> <back> <pattern> */
+            TRACE(("|%p|%p|ASSERT %d\n", ctx->pattern,
+                   ctx->ptr, ctx->pattern[1]));
+            state->ptr = ctx->ptr - ctx->pattern[1];
+            if (state->ptr < state->beginning)
+                RETURN_FAILURE;
+            DO_JUMP(JUMP_ASSERT, jump_assert, ctx->pattern+2);
+            RETURN_ON_FAILURE(ret);
+            ctx->pattern += ctx->pattern[0];
+            break;
+
+        case SRE_OP_ASSERT_NOT:
+            /* assert not subpattern */
+            /* <ASSERT_NOT> <skip> <back> <pattern> */
+            TRACE(("|%p|%p|ASSERT_NOT %d\n", ctx->pattern,
+                   ctx->ptr, ctx->pattern[1]));
+            state->ptr = ctx->ptr - ctx->pattern[1];
+            if (state->ptr >= state->beginning) {
+                DO_JUMP(JUMP_ASSERT_NOT, jump_assert_not, ctx->pattern+2);
+                if (ret) {
+                    RETURN_ON_ERROR(ret);
+                    RETURN_FAILURE;
+                }
+            }
+            ctx->pattern += ctx->pattern[0];
+            break;
+
+        case SRE_OP_FAILURE:
+            /* immediate failure */
+            TRACE(("|%p|%p|FAILURE\n", ctx->pattern, ctx->ptr));
+            RETURN_FAILURE;
+
+        default:
+            TRACE(("|%p|%p|UNKNOWN %d\n", ctx->pattern, ctx->ptr,
+                   ctx->pattern[-1]));
+            RETURN_ERROR(SRE_ERROR_ILLEGAL);
+        }
+    }
+
+exit:
+    ctx_pos = ctx->last_ctx_pos;
+    jump = ctx->jump;
+    DATA_POP_DISCARD(ctx);
+    if (ctx_pos == -1)
+        return ret;
+    DATA_LOOKUP_AT(SRE_MATCH_CONTEXT, ctx, ctx_pos);
+
+    switch (jump) {
+        case JUMP_MAX_UNTIL_2:
+            TRACE(("|%p|%p|JUMP_MAX_UNTIL_2\n", ctx->pattern, ctx->ptr));
+            goto jump_max_until_2;
+        case JUMP_MAX_UNTIL_3:
+            TRACE(("|%p|%p|JUMP_MAX_UNTIL_3\n", ctx->pattern, ctx->ptr));
+            goto jump_max_until_3;
+        case JUMP_MIN_UNTIL_2:
+            TRACE(("|%p|%p|JUMP_MIN_UNTIL_2\n", ctx->pattern, ctx->ptr));
+            goto jump_min_until_2;
+        case JUMP_MIN_UNTIL_3:
+            TRACE(("|%p|%p|JUMP_MIN_UNTIL_3\n", ctx->pattern, ctx->ptr));
+            goto jump_min_until_3;
+        case JUMP_BRANCH:
+            TRACE(("|%p|%p|JUMP_BRANCH\n", ctx->pattern, ctx->ptr));
+            goto jump_branch;
+        case JUMP_MAX_UNTIL_1:
+            TRACE(("|%p|%p|JUMP_MAX_UNTIL_1\n", ctx->pattern, ctx->ptr));
+            goto jump_max_until_1;
+        case JUMP_MIN_UNTIL_1:
+            TRACE(("|%p|%p|JUMP_MIN_UNTIL_1\n", ctx->pattern, ctx->ptr));
+            goto jump_min_until_1;
+        case JUMP_REPEAT:
+            TRACE(("|%p|%p|JUMP_REPEAT\n", ctx->pattern, ctx->ptr));
+            goto jump_repeat;
+        case JUMP_REPEAT_ONE_1:
+            TRACE(("|%p|%p|JUMP_REPEAT_ONE_1\n", ctx->pattern, ctx->ptr));
+            goto jump_repeat_one_1;
+        case JUMP_REPEAT_ONE_2:
+            TRACE(("|%p|%p|JUMP_REPEAT_ONE_2\n", ctx->pattern, ctx->ptr));
+            goto jump_repeat_one_2;
+        case JUMP_MIN_REPEAT_ONE:
+            TRACE(("|%p|%p|JUMP_MIN_REPEAT_ONE\n", ctx->pattern, ctx->ptr));
+            goto jump_min_repeat_one;
+        case JUMP_ASSERT:
+            TRACE(("|%p|%p|JUMP_ASSERT\n", ctx->pattern, ctx->ptr));
+            goto jump_assert;
+        case JUMP_ASSERT_NOT:
+            TRACE(("|%p|%p|JUMP_ASSERT_NOT\n", ctx->pattern, ctx->ptr));
+            goto jump_assert_not;
+        case JUMP_NONE:
+            TRACE(("|%p|%p|RETURN %d\n", ctx->pattern, ctx->ptr, ret));
+            break;
+    }
+
+    return ret; /* should never get here */
+}
+
+LOCAL(Py_ssize_t)
+SRE_SEARCH(SRE_STATE* state, SRE_CODE* pattern)
+{
+    SRE_CHAR* ptr = (SRE_CHAR *)state->start;
+    SRE_CHAR* end = (SRE_CHAR *)state->end;
+    Py_ssize_t status = 0;
+    Py_ssize_t prefix_len = 0;
+    Py_ssize_t prefix_skip = 0;
+    SRE_CODE* prefix = NULL;
+    SRE_CODE* charset = NULL;
+    SRE_CODE* overlap = NULL;
+    int flags = 0;
+
+    if (pattern[0] == SRE_OP_INFO) {
+        /* optimization info block */
+        /* <INFO> <1=skip> <2=flags> <3=min> <4=max> <5=prefix info>  */
+
+        flags = pattern[2];
+
+        if (pattern[3] > 1) {
+            /* adjust end point (but make sure we leave at least one
+               character in there, so literal search will work) */
+            end -= pattern[3]-1;
+            if (end <= ptr)
+                end = ptr+1;
+        }
+
+        if (flags & SRE_INFO_PREFIX) {
+            /* pattern starts with a known prefix */
+            /* <length> <skip> <prefix data> <overlap data> */
+            prefix_len = pattern[5];
+            prefix_skip = pattern[6];
+            prefix = pattern + 7;
+            overlap = prefix + prefix_len - 1;
+        } else if (flags & SRE_INFO_CHARSET)
+            /* pattern starts with a character from a known set */
+            /* <charset> */
+            charset = pattern + 5;
+
+        pattern += 1 + pattern[1];
+    }
+
+    TRACE(("prefix = %p %d %d\n", prefix, prefix_len, prefix_skip));
+    TRACE(("charset = %p\n", charset));
+
+#if defined(USE_FAST_SEARCH)
+    if (prefix_len > 1) {
+        /* pattern starts with a known prefix.  use the overlap
+           table to skip forward as fast as we possibly can */
+        Py_ssize_t i = 0;
+        end = (SRE_CHAR *)state->end;
+        while (ptr < end) {
+            for (;;) {
+                if ((SRE_CODE) ptr[0] != prefix[i]) {
+                    if (!i)
+                        break;
+                    else
+                        i = overlap[i];
+                } else {
+                    if (++i == prefix_len) {
+                        /* found a potential match */
+                        TRACE(("|%p|%p|SEARCH SCAN\n", pattern, ptr));
+                        state->start = ptr + 1 - prefix_len;
+                        state->ptr = ptr + 1 - prefix_len + prefix_skip;
+                        if (flags & SRE_INFO_LITERAL)
+                            return 1; /* we got all of it */
+                        status = SRE_MATCH(state, pattern + 2*prefix_skip);
+                        if (status != 0)
+                            return status;
+                        /* close but no cigar -- try again */
+                        i = overlap[i];
+                    }
+                    break;
+                }
+            }
+            ptr++;
+        }
+        return 0;
+    }
+#endif
+
+    if (pattern[0] == SRE_OP_LITERAL) {
+        /* pattern starts with a literal character.  this is used
+           for short prefixes, and if fast search is disabled */
+        SRE_CODE chr = pattern[1];
+        end = (SRE_CHAR *)state->end;
+        for (;;) {
+            while (ptr < end && (SRE_CODE) ptr[0] != chr)
+                ptr++;
+            if (ptr >= end)
+                return 0;
+            TRACE(("|%p|%p|SEARCH LITERAL\n", pattern, ptr));
+            state->start = ptr;
+            state->ptr = ++ptr;
+            if (flags & SRE_INFO_LITERAL)
+                return 1; /* we got all of it */
+            status = SRE_MATCH(state, pattern + 2);
+            if (status != 0)
+                break;
+        }
+    } else if (charset) {
+        /* pattern starts with a character from a known set */
+        end = (SRE_CHAR *)state->end;
+        for (;;) {
+            while (ptr < end && !SRE_CHARSET(charset, ptr[0]))
+                ptr++;
+            if (ptr >= end)
+                return 0;
+            TRACE(("|%p|%p|SEARCH CHARSET\n", pattern, ptr));
+            state->start = ptr;
+            state->ptr = ptr;
+            status = SRE_MATCH(state, pattern);
+            if (status != 0)
+                break;
+            ptr++;
+        }
+    } else
+        /* general case */
+        while (ptr <= end) {
+            TRACE(("|%p|%p|SEARCH\n", pattern, ptr));
+            state->start = state->ptr = ptr++;
+            status = SRE_MATCH(state, pattern);
+            if (status != 0)
+                break;
+        }
+
+    return status;
+}
+
+LOCAL(int)
+SRE_LITERAL_TEMPLATE(SRE_CHAR* ptr, Py_ssize_t len)
+{
+    /* check if given string is a literal template (i.e. no escapes) */
+    while (len-- > 0)
+        if (*ptr++ == '\\')
+            return 0;
+    return 1;
+}
+
+#if !defined(SRE_RECURSIVE)
+
+/* -------------------------------------------------------------------- */
+/* factories and destructors */
+
+/* see sre.h for object declarations */
+static PyObject*pattern_new_match(PatternObject*, SRE_STATE*, int);
+static PyObject*pattern_scanner(PatternObject*, PyObject*);
+
+static PyObject *
+sre_codesize(PyObject* self, PyObject *unused)
+{
+    return Py_BuildValue("l", sizeof(SRE_CODE));
+}
+
+static PyObject *
+sre_getlower(PyObject* self, PyObject* args)
+{
+    int character, flags;
+    if (!PyArg_ParseTuple(args, "ii", &character, &flags))
+        return NULL;
+    if (flags & SRE_FLAG_LOCALE)
+        return Py_BuildValue("i", sre_lower_locale(character));
+    if (flags & SRE_FLAG_UNICODE)
+#if defined(HAVE_UNICODE)
+        return Py_BuildValue("i", sre_lower_unicode(character));
+#else
+        return Py_BuildValue("i", sre_lower_locale(character));
+#endif
+    return Py_BuildValue("i", sre_lower(character));
+}
+
+LOCAL(void)
+state_reset(SRE_STATE* state)
+{
+    /* FIXME: dynamic! */
+    /*memset(state->mark, 0, sizeof(*state->mark) * SRE_MARK_SIZE);*/
+
+    state->lastmark = -1;
+    state->lastindex = -1;
+
+    state->repeat = NULL;
+
+    data_stack_dealloc(state);
+}
+
+static void*
+getstring(PyObject* string, Py_ssize_t* p_length, int* p_charsize)
+{
+    /* given a python object, return a data pointer, a length (in
+       characters), and a character size.  return NULL if the object
+       is not a string (or not compatible) */
+
+    PyBufferProcs *buffer;
+    Py_ssize_t size, bytes;
+    int charsize;
+    void* ptr;
+
+#if defined(HAVE_UNICODE)
+    if (PyUnicode_Check(string)) {
+        /* unicode strings doesn't always support the buffer interface */
+        ptr = (void*) PyUnicode_AS_DATA(string);
+        bytes = PyUnicode_GET_DATA_SIZE(string);
+        size = PyUnicode_GET_SIZE(string);
+        charsize = sizeof(Py_UNICODE);
+
+    } else {
+#endif
+
+    /* get pointer to string buffer */
+    buffer = Py_TYPE(string)->tp_as_buffer;
+    if (!buffer || !buffer->bf_getreadbuffer || !buffer->bf_getsegcount ||
+        buffer->bf_getsegcount(string, NULL) != 1) {
+        PyErr_SetString(PyExc_TypeError, "expected string or buffer");
+        return NULL;
+    }
+
+    /* determine buffer size */
+    bytes = buffer->bf_getreadbuffer(string, 0, &ptr);
+    if (bytes < 0) {
+        PyErr_SetString(PyExc_TypeError, "buffer has negative size");
+        return NULL;
+    }
+
+    /* determine character size */
+#if PY_VERSION_HEX >= 0x01060000
+    size = PyObject_Size(string);
+#else
+    size = PyObject_Length(string);
+#endif
+
+    if (PyString_Check(string) || bytes == size)
+        charsize = 1;
+#if defined(HAVE_UNICODE)
+    else if (bytes == (Py_ssize_t) (size * sizeof(Py_UNICODE)))
+        charsize = sizeof(Py_UNICODE);
+#endif
+    else {
+        PyErr_SetString(PyExc_TypeError, "buffer size mismatch");
+        return NULL;
+    }
+
+#if defined(HAVE_UNICODE)
+    }
+#endif
+
+    *p_length = size;
+    *p_charsize = charsize;
+
+    return ptr;
+}
+
+LOCAL(PyObject*)
+state_init(SRE_STATE* state, PatternObject* pattern, PyObject* string,
+           Py_ssize_t start, Py_ssize_t end)
+{
+    /* prepare state object */
+
+    Py_ssize_t length;
+    int charsize;
+    void* ptr;
+
+    memset(state, 0, sizeof(SRE_STATE));
+
+    state->lastmark = -1;
+    state->lastindex = -1;
+
+    ptr = getstring(string, &length, &charsize);
+    if (!ptr)
+        return NULL;
+
+    /* adjust boundaries */
+    if (start < 0)
+        start = 0;
+    else if (start > length)
+        start = length;
+
+    if (end < 0)
+        end = 0;
+    else if (end > length)
+        end = length;
+
+    state->charsize = charsize;
+
+    state->beginning = ptr;
+
+    state->start = (void*) ((char*) ptr + start * state->charsize);
+    state->end = (void*) ((char*) ptr + end * state->charsize);
+
+    Py_INCREF(string);
+    state->string = string;
+    state->pos = start;
+    state->endpos = end;
+
+    if (pattern->flags & SRE_FLAG_LOCALE)
+        state->lower = sre_lower_locale;
+    else if (pattern->flags & SRE_FLAG_UNICODE)
+#if defined(HAVE_UNICODE)
+        state->lower = sre_lower_unicode;
+#else
+        state->lower = sre_lower_locale;
+#endif
+    else
+        state->lower = sre_lower;
+
+    return string;
+}
+
+LOCAL(void)
+state_fini(SRE_STATE* state)
+{
+    Py_XDECREF(state->string);
+    data_stack_dealloc(state);
+}
+
+/* calculate offset from start of string */
+#define STATE_OFFSET(state, member)\
+    (((char*)(member) - (char*)(state)->beginning) / (state)->charsize)
+
+LOCAL(PyObject*)
+state_getslice(SRE_STATE* state, Py_ssize_t index, PyObject* string, int empty)
+{
+    Py_ssize_t i, j;
+
+    index = (index - 1) * 2;
+
+    if (string == Py_None || index >= state->lastmark || !state->mark[index] || !state->mark[index+1]) {
+        if (empty)
+            /* want empty string */
+            i = j = 0;
+        else {
+            Py_INCREF(Py_None);
+            return Py_None;
+        }
+    } else {
+        i = STATE_OFFSET(state, state->mark[index]);
+        j = STATE_OFFSET(state, state->mark[index+1]);
+    }
+
+    return PySequence_GetSlice(string, i, j);
+}
+
+static void
+pattern_error(int status)
+{
+    switch (status) {
+    case SRE_ERROR_RECURSION_LIMIT:
+        PyErr_SetString(
+            PyExc_RuntimeError,
+            "maximum recursion limit exceeded"
+            );
+        break;
+    case SRE_ERROR_MEMORY:
+        PyErr_NoMemory();
+        break;
+    case SRE_ERROR_INTERRUPTED:
+    /* An exception has already been raised, so let it fly */
+        break;
+    default:
+        /* other error codes indicate compiler/engine bugs */
+        PyErr_SetString(
+            PyExc_RuntimeError,
+            "internal error in regular expression engine"
+            );
+    }
+}
+
+static void
+pattern_dealloc(PatternObject* self)
+{
+    if (self->weakreflist != NULL)
+        PyObject_ClearWeakRefs((PyObject *) self);
+    Py_XDECREF(self->pattern);
+    Py_XDECREF(self->groupindex);
+    Py_XDECREF(self->indexgroup);
+    PyObject_DEL(self);
+}
+
+static PyObject*
+pattern_match(PatternObject* self, PyObject* args, PyObject* kw)
+{
+    SRE_STATE state;
+    int status;
+
+    PyObject* string;
+    Py_ssize_t start = 0;
+    Py_ssize_t end = PY_SSIZE_T_MAX;
+    static char* kwlist[] = { "pattern", "pos", "endpos", NULL };
+    if (!PyArg_ParseTupleAndKeywords(args, kw, "O|nn:match", kwlist,
+                                     &string, &start, &end))
+        return NULL;
+
+    string = state_init(&state, self, string, start, end);
+    if (!string)
+        return NULL;
+
+    state.ptr = state.start;
+
+    TRACE(("|%p|%p|MATCH\n", PatternObject_GetCode(self), state.ptr));
+
+    if (state.charsize == 1) {
+        status = sre_match(&state, PatternObject_GetCode(self));
+    } else {
+#if defined(HAVE_UNICODE)
+        status = sre_umatch(&state, PatternObject_GetCode(self));
+#endif
+    }
+
+    TRACE(("|%p|%p|END\n", PatternObject_GetCode(self), state.ptr));
+    if (PyErr_Occurred())
+        return NULL;
+
+    state_fini(&state);
+
+    return pattern_new_match(self, &state, status);
+}
+
+static PyObject*
+pattern_search(PatternObject* self, PyObject* args, PyObject* kw)
+{
+    SRE_STATE state;
+    int status;
+
+    PyObject* string;
+    Py_ssize_t start = 0;
+    Py_ssize_t end = PY_SSIZE_T_MAX;
+    static char* kwlist[] = { "pattern", "pos", "endpos", NULL };
+    if (!PyArg_ParseTupleAndKeywords(args, kw, "O|nn:search", kwlist,
+                                     &string, &start, &end))
+        return NULL;
+
+    string = state_init(&state, self, string, start, end);
+    if (!string)
+        return NULL;
+
+    TRACE(("|%p|%p|SEARCH\n", PatternObject_GetCode(self), state.ptr));
+
+    if (state.charsize == 1) {
+        status = sre_search(&state, PatternObject_GetCode(self));
+    } else {
+#if defined(HAVE_UNICODE)
+        status = sre_usearch(&state, PatternObject_GetCode(self));
+#endif
+    }
+
+    TRACE(("|%p|%p|END\n", PatternObject_GetCode(self), state.ptr));
+
+    state_fini(&state);
+
+    if (PyErr_Occurred())
+        return NULL;
+
+    return pattern_new_match(self, &state, status);
+}
+
+static PyObject*
+call(char* module, char* function, PyObject* args)
+{
+    PyObject* name;
+    PyObject* mod;
+    PyObject* func;
+    PyObject* result;
+
+    if (!args)
+        return NULL;
+    name = PyString_FromString(module);
+    if (!name)
+        return NULL;
+    mod = PyImport_Import(name);
+    Py_DECREF(name);
+    if (!mod)
+        return NULL;
+    func = PyObject_GetAttrString(mod, function);
+    Py_DECREF(mod);
+    if (!func)
+        return NULL;
+    result = PyObject_CallObject(func, args);
+    Py_DECREF(func);
+    Py_DECREF(args);
+    return result;
+}
+
+#ifdef USE_BUILTIN_COPY
+static int
+deepcopy(PyObject** object, PyObject* memo)
+{
+    PyObject* copy;
+
+    copy = call(
+        "copy", "deepcopy",
+        PyTuple_Pack(2, *object, memo)
+        );
+    if (!copy)
+        return 0;
+
+    Py_DECREF(*object);
+    *object = copy;
+
+    return 1; /* success */
+}
+#endif
+
+static PyObject*
+join_list(PyObject* list, PyObject* string)
+{
+    /* join list elements */
+
+    PyObject* joiner;
+#if PY_VERSION_HEX >= 0x01060000
+    PyObject* function;
+    PyObject* args;
+#endif
+    PyObject* result;
+
+    joiner = PySequence_GetSlice(string, 0, 0);
+    if (!joiner)
+        return NULL;
+
+    if (PyList_GET_SIZE(list) == 0) {
+        Py_DECREF(list);
+        return joiner;
+    }
+
+#if PY_VERSION_HEX >= 0x01060000
+    function = PyObject_GetAttrString(joiner, "join");
+    if (!function) {
+        Py_DECREF(joiner);
+        return NULL;
+    }
+    args = PyTuple_New(1);
+    if (!args) {
+        Py_DECREF(function);
+        Py_DECREF(joiner);
+        return NULL;
+    }
+    PyTuple_SET_ITEM(args, 0, list);
+    result = PyObject_CallObject(function, args);
+    Py_DECREF(args); /* also removes list */
+    Py_DECREF(function);
+#else
+    result = call(
+        "string", "join",
+        PyTuple_Pack(2, list, joiner)
+        );
+#endif
+    Py_DECREF(joiner);
+
+    return result;
+}
+
+static PyObject*
+pattern_findall(PatternObject* self, PyObject* args, PyObject* kw)
+{
+    SRE_STATE state;
+    PyObject* list;
+    int status;
+    Py_ssize_t i, b, e;
+
+    PyObject* string;
+    Py_ssize_t start = 0;
+    Py_ssize_t end = PY_SSIZE_T_MAX;
+    static char* kwlist[] = { "source", "pos", "endpos", NULL };
+    if (!PyArg_ParseTupleAndKeywords(args, kw, "O|nn:findall", kwlist,
+                                     &string, &start, &end))
+        return NULL;
+
+    string = state_init(&state, self, string, start, end);
+    if (!string)
+        return NULL;
+
+    list = PyList_New(0);
+    if (!list) {
+        state_fini(&state);
+        return NULL;
+    }
+
+    while (state.start <= state.end) {
+
+        PyObject* item;
+
+        state_reset(&state);
+
+        state.ptr = state.start;
+
+        if (state.charsize == 1) {
+            status = sre_search(&state, PatternObject_GetCode(self));
+        } else {
+#if defined(HAVE_UNICODE)
+            status = sre_usearch(&state, PatternObject_GetCode(self));
+#endif
+        }
+
+	if (PyErr_Occurred())
+	    goto error;
+
+        if (status <= 0) {
+            if (status == 0)
+                break;
+            pattern_error(status);
+            goto error;
+        }
+
+        /* don't bother to build a match object */
+        switch (self->groups) {
+        case 0:
+            b = STATE_OFFSET(&state, state.start);
+            e = STATE_OFFSET(&state, state.ptr);
+            item = PySequence_GetSlice(string, b, e);
+            if (!item)
+                goto error;
+            break;
+        case 1:
+            item = state_getslice(&state, 1, string, 1);
+            if (!item)
+                goto error;
+            break;
+        default:
+            item = PyTuple_New(self->groups);
+            if (!item)
+                goto error;
+            for (i = 0; i < self->groups; i++) {
+                PyObject* o = state_getslice(&state, i+1, string, 1);
+                if (!o) {
+                    Py_DECREF(item);
+                    goto error;
+                }
+                PyTuple_SET_ITEM(item, i, o);
+            }
+            break;
+        }
+
+        status = PyList_Append(list, item);
+        Py_DECREF(item);
+        if (status < 0)
+            goto error;
+
+        if (state.ptr == state.start)
+            state.start = (void*) ((char*) state.ptr + state.charsize);
+        else
+            state.start = state.ptr;
+
+    }
+
+    state_fini(&state);
+    return list;
+
+error:
+    Py_DECREF(list);
+    state_fini(&state);
+    return NULL;
+
+}
+
+#if PY_VERSION_HEX >= 0x02020000
+static PyObject*
+pattern_finditer(PatternObject* pattern, PyObject* args)
+{
+    PyObject* scanner;
+    PyObject* search;
+    PyObject* iterator;
+
+    scanner = pattern_scanner(pattern, args);
+    if (!scanner)
+        return NULL;
+
+    search = PyObject_GetAttrString(scanner, "search");
+    Py_DECREF(scanner);
+    if (!search)
+        return NULL;
+
+    iterator = PyCallIter_New(search, Py_None);
+    Py_DECREF(search);
+
+    return iterator;
+}
+#endif
+
+static PyObject*
+pattern_split(PatternObject* self, PyObject* args, PyObject* kw)
+{
+    SRE_STATE state;
+    PyObject* list;
+    PyObject* item;
+    int status;
+    Py_ssize_t n;
+    Py_ssize_t i;
+    void* last;
+
+    PyObject* string;
+    Py_ssize_t maxsplit = 0;
+    static char* kwlist[] = { "source", "maxsplit", NULL };
+    if (!PyArg_ParseTupleAndKeywords(args, kw, "O|n:split", kwlist,
+                                     &string, &maxsplit))
+        return NULL;
+
+    string = state_init(&state, self, string, 0, PY_SSIZE_T_MAX);
+    if (!string)
+        return NULL;
+
+    list = PyList_New(0);
+    if (!list) {
+        state_fini(&state);
+        return NULL;
+    }
+
+    n = 0;
+    last = state.start;
+
+    while (!maxsplit || n < maxsplit) {
+
+        state_reset(&state);
+
+        state.ptr = state.start;
+
+        if (state.charsize == 1) {
+            status = sre_search(&state, PatternObject_GetCode(self));
+        } else {
+#if defined(HAVE_UNICODE)
+            status = sre_usearch(&state, PatternObject_GetCode(self));
+#endif
+        }
+
+	if (PyErr_Occurred())
+	    goto error;
+
+        if (status <= 0) {
+            if (status == 0)
+                break;
+            pattern_error(status);
+            goto error;
+        }
+
+        if (state.start == state.ptr) {
+            if (last == state.end)
+                break;
+            /* skip one character */
+            state.start = (void*) ((char*) state.ptr + state.charsize);
+            continue;
+        }
+
+        /* get segment before this match */
+        item = PySequence_GetSlice(
+            string, STATE_OFFSET(&state, last),
+            STATE_OFFSET(&state, state.start)
+            );
+        if (!item)
+            goto error;
+        status = PyList_Append(list, item);
+        Py_DECREF(item);
+        if (status < 0)
+            goto error;
+
+        /* add groups (if any) */
+        for (i = 0; i < self->groups; i++) {
+            item = state_getslice(&state, i+1, string, 0);
+            if (!item)
+                goto error;
+            status = PyList_Append(list, item);
+            Py_DECREF(item);
+            if (status < 0)
+                goto error;
+        }
+
+        n = n + 1;
+
+        last = state.start = state.ptr;
+
+    }
+
+    /* get segment following last match (even if empty) */
+    item = PySequence_GetSlice(
+        string, STATE_OFFSET(&state, last), state.endpos
+        );
+    if (!item)
+        goto error;
+    status = PyList_Append(list, item);
+    Py_DECREF(item);
+    if (status < 0)
+        goto error;
+
+    state_fini(&state);
+    return list;
+
+error:
+    Py_DECREF(list);
+    state_fini(&state);
+    return NULL;
+
+}
+
+static PyObject*
+pattern_subx(PatternObject* self, PyObject* ptemplate, PyObject* string,
+             Py_ssize_t count, Py_ssize_t subn)
+{
+    SRE_STATE state;
+    PyObject* list;
+    PyObject* item;
+    PyObject* filter;
+    PyObject* args;
+    PyObject* match;
+    void* ptr;
+    int status;
+    Py_ssize_t n;
+    Py_ssize_t i, b, e;
+    int bint;
+    int filter_is_callable;
+
+    if (PyCallable_Check(ptemplate)) {
+        /* sub/subn takes either a function or a template */
+        filter = ptemplate;
+        Py_INCREF(filter);
+        filter_is_callable = 1;
+    } else {
+        /* if not callable, check if it's a literal string */
+        int literal;
+        ptr = getstring(ptemplate, &n, &bint);
+        b = bint;
+        if (ptr) {
+            if (b == 1) {
+		    literal = sre_literal_template((unsigned char *)ptr, n);
+            } else {
+#if defined(HAVE_UNICODE)
+		    literal = sre_uliteral_template((Py_UNICODE *)ptr, n);
+#endif
+            }
+        } else {
+            PyErr_Clear();
+            literal = 0;
+        }
+        if (literal) {
+            filter = ptemplate;
+            Py_INCREF(filter);
+            filter_is_callable = 0;
+        } else {
+            /* not a literal; hand it over to the template compiler */
+            filter = call(
+                SRE_PY_MODULE, "_subx",
+                PyTuple_Pack(2, self, ptemplate)
+                );
+            if (!filter)
+                return NULL;
+            filter_is_callable = PyCallable_Check(filter);
+        }
+    }
+
+    string = state_init(&state, self, string, 0, PY_SSIZE_T_MAX);
+    if (!string) {
+        Py_DECREF(filter);
+        return NULL;
+    }
+
+    list = PyList_New(0);
+    if (!list) {
+        Py_DECREF(filter);
+        state_fini(&state);
+        return NULL;
+    }
+
+    n = i = 0;
+
+    while (!count || n < count) {
+
+        state_reset(&state);
+
+        state.ptr = state.start;
+
+        if (state.charsize == 1) {
+            status = sre_search(&state, PatternObject_GetCode(self));
+        } else {
+#if defined(HAVE_UNICODE)
+            status = sre_usearch(&state, PatternObject_GetCode(self));
+#endif
+        }
+
+	if (PyErr_Occurred())
+	    goto error;
+
+        if (status <= 0) {
+            if (status == 0)
+                break;
+            pattern_error(status);
+            goto error;
+        }
+
+        b = STATE_OFFSET(&state, state.start);
+        e = STATE_OFFSET(&state, state.ptr);
+
+        if (i < b) {
+            /* get segment before this match */
+            item = PySequence_GetSlice(string, i, b);
+            if (!item)
+                goto error;
+            status = PyList_Append(list, item);
+            Py_DECREF(item);
+            if (status < 0)
+                goto error;
+
+        } else if (i == b && i == e && n > 0)
+            /* ignore empty match on latest position */
+            goto next;
+
+        if (filter_is_callable) {
+            /* pass match object through filter */
+            match = pattern_new_match(self, &state, 1);
+            if (!match)
+                goto error;
+            args = PyTuple_Pack(1, match);
+            if (!args) {
+                Py_DECREF(match);
+                goto error;
+            }
+            item = PyObject_CallObject(filter, args);
+            Py_DECREF(args);
+            Py_DECREF(match);
+            if (!item)
+                goto error;
+        } else {
+            /* filter is literal string */
+            item = filter;
+            Py_INCREF(item);
+        }
+
+        /* add to list */
+        if (item != Py_None) {
+            status = PyList_Append(list, item);
+            Py_DECREF(item);
+            if (status < 0)
+                goto error;
+        }
+
+        i = e;
+        n = n + 1;
+
+next:
+        /* move on */
+        if (state.ptr == state.start)
+            state.start = (void*) ((char*) state.ptr + state.charsize);
+        else
+            state.start = state.ptr;
+
+    }
+
+    /* get segment following last match */
+    if (i < state.endpos) {
+        item = PySequence_GetSlice(string, i, state.endpos);
+        if (!item)
+            goto error;
+        status = PyList_Append(list, item);
+        Py_DECREF(item);
+        if (status < 0)
+            goto error;
+    }
+
+    state_fini(&state);
+
+    Py_DECREF(filter);
+
+    /* convert list to single string (also removes list) */
+    item = join_list(list, string);
+
+    if (!item)
+        return NULL;
+
+    if (subn)
+        return Py_BuildValue("Ni", item, n);
+
+    return item;
+
+error:
+    Py_DECREF(list);
+    state_fini(&state);
+    Py_DECREF(filter);
+    return NULL;
+
+}
+
+static PyObject*
+pattern_sub(PatternObject* self, PyObject* args, PyObject* kw)
+{
+    PyObject* ptemplate;
+    PyObject* string;
+    Py_ssize_t count = 0;
+    static char* kwlist[] = { "repl", "string", "count", NULL };
+    if (!PyArg_ParseTupleAndKeywords(args, kw, "OO|n:sub", kwlist,
+                                     &ptemplate, &string, &count))
+        return NULL;
+
+    return pattern_subx(self, ptemplate, string, count, 0);
+}
+
+static PyObject*
+pattern_subn(PatternObject* self, PyObject* args, PyObject* kw)
+{
+    PyObject* ptemplate;
+    PyObject* string;
+    Py_ssize_t count = 0;
+    static char* kwlist[] = { "repl", "string", "count", NULL };
+    if (!PyArg_ParseTupleAndKeywords(args, kw, "OO|n:subn", kwlist,
+                                     &ptemplate, &string, &count))
+        return NULL;
+
+    return pattern_subx(self, ptemplate, string, count, 1);
+}
+
+static PyObject*
+pattern_copy(PatternObject* self, PyObject *unused)
+{
+#ifdef USE_BUILTIN_COPY
+    PatternObject* copy;
+    int offset;
+
+    copy = PyObject_NEW_VAR(PatternObject, &Pattern_Type, self->codesize);
+    if (!copy)
+        return NULL;
+
+    offset = offsetof(PatternObject, groups);
+
+    Py_XINCREF(self->groupindex);
+    Py_XINCREF(self->indexgroup);
+    Py_XINCREF(self->pattern);
+
+    memcpy((char*) copy + offset, (char*) self + offset,
+           sizeof(PatternObject) + self->codesize * sizeof(SRE_CODE) - offset);
+    copy->weakreflist = NULL;
+
+    return (PyObject*) copy;
+#else
+    PyErr_SetString(PyExc_TypeError, "cannot copy this pattern object");
+    return NULL;
+#endif
+}
+
+static PyObject*
+pattern_deepcopy(PatternObject* self, PyObject* memo)
+{
+#ifdef USE_BUILTIN_COPY
+    PatternObject* copy;
+
+    copy = (PatternObject*) pattern_copy(self);
+    if (!copy)
+        return NULL;
+
+    if (!deepcopy(&copy->groupindex, memo) ||
+        !deepcopy(&copy->indexgroup, memo) ||
+        !deepcopy(&copy->pattern, memo)) {
+        Py_DECREF(copy);
+        return NULL;
+    }
+
+#else
+    PyErr_SetString(PyExc_TypeError, "cannot deepcopy this pattern object");
+    return NULL;
+#endif
+}
+
+PyDoc_STRVAR(pattern_match_doc,
+"match(string[, pos[, endpos]]) --> match object or None.\n\
+    Matches zero or more characters at the beginning of the string");
+
+PyDoc_STRVAR(pattern_search_doc,
+"search(string[, pos[, endpos]]) --> match object or None.\n\
+    Scan through string looking for a match, and return a corresponding\n\
+    MatchObject instance. Return None if no position in the string matches.");
+
+PyDoc_STRVAR(pattern_split_doc,
+"split(string[, maxsplit = 0])  --> list.\n\
+    Split string by the occurrences of pattern.");
+
+PyDoc_STRVAR(pattern_findall_doc,
+"findall(string[, pos[, endpos]]) --> list.\n\
+   Return a list of all non-overlapping matches of pattern in string.");
+
+PyDoc_STRVAR(pattern_finditer_doc,
+"finditer(string[, pos[, endpos]]) --> iterator.\n\
+    Return an iterator over all non-overlapping matches for the \n\
+    RE pattern in string. For each match, the iterator returns a\n\
+    match object.");
+
+PyDoc_STRVAR(pattern_sub_doc,
+"sub(repl, string[, count = 0]) --> newstring\n\
+    Return the string obtained by replacing the leftmost non-overlapping\n\
+    occurrences of pattern in string by the replacement repl.");
+
+PyDoc_STRVAR(pattern_subn_doc,
+"subn(repl, string[, count = 0]) --> (newstring, number of subs)\n\
+    Return the tuple (new_string, number_of_subs_made) found by replacing\n\
+    the leftmost non-overlapping occurrences of pattern with the\n\
+    replacement repl.");
+
+PyDoc_STRVAR(pattern_doc, "Compiled regular expression objects");
+
+static PyMethodDef pattern_methods[] = {
+    {"match", (PyCFunction) pattern_match, METH_VARARGS|METH_KEYWORDS,
+	pattern_match_doc},
+    {"search", (PyCFunction) pattern_search, METH_VARARGS|METH_KEYWORDS,
+	pattern_search_doc},
+    {"sub", (PyCFunction) pattern_sub, METH_VARARGS|METH_KEYWORDS,
+	pattern_sub_doc},
+    {"subn", (PyCFunction) pattern_subn, METH_VARARGS|METH_KEYWORDS,
+	pattern_subn_doc},
+    {"split", (PyCFunction) pattern_split, METH_VARARGS|METH_KEYWORDS,
+	pattern_split_doc},
+    {"findall", (PyCFunction) pattern_findall, METH_VARARGS|METH_KEYWORDS,
+	pattern_findall_doc},
+#if PY_VERSION_HEX >= 0x02020000
+    {"finditer", (PyCFunction) pattern_finditer, METH_VARARGS,
+	pattern_finditer_doc},
+#endif
+    {"scanner", (PyCFunction) pattern_scanner, METH_VARARGS},
+    {"__copy__", (PyCFunction) pattern_copy, METH_NOARGS},
+    {"__deepcopy__", (PyCFunction) pattern_deepcopy, METH_O},
+    {NULL, NULL}
+};
+
+static PyObject*
+pattern_getattr(PatternObject* self, char* name)
+{
+    PyObject* res;
+
+    res = Py_FindMethod(pattern_methods, (PyObject*) self, name);
+
+    if (res)
+        return res;
+
+    PyErr_Clear();
+
+    /* attributes */
+    if (!strcmp(name, "pattern")) {
+        Py_INCREF(self->pattern);
+        return self->pattern;
+    }
+
+    if (!strcmp(name, "flags"))
+        return Py_BuildValue("i", self->flags);
+
+    if (!strcmp(name, "groups"))
+        return Py_BuildValue("i", self->groups);
+
+    if (!strcmp(name, "groupindex") && self->groupindex) {
+        Py_INCREF(self->groupindex);
+        return self->groupindex;
+    }
+
+    PyErr_SetString(PyExc_AttributeError, name);
+    return NULL;
+}
+
+statichere PyTypeObject Pattern_Type = {
+    PyObject_HEAD_INIT(NULL)
+    0, "_" SRE_MODULE ".SRE_Pattern",
+    sizeof(PatternObject), sizeof(SRE_CODE),
+    (destructor)pattern_dealloc, /*tp_dealloc*/
+    0, /*tp_print*/
+    (getattrfunc)pattern_getattr, /*tp_getattr*/
+    0,					/* tp_setattr */
+    0,					/* tp_compare */
+    0,					/* tp_repr */
+    0,					/* tp_as_number */
+    0,					/* tp_as_sequence */
+    0,					/* tp_as_mapping */
+    0,					/* tp_hash */
+    0,					/* tp_call */
+    0,					/* tp_str */
+    0,					/* tp_getattro */
+    0,					/* tp_setattro */
+    0,					/* tp_as_buffer */
+    Py_TPFLAGS_HAVE_WEAKREFS,		/* tp_flags */
+    pattern_doc,			/* tp_doc */
+    0,					/* tp_traverse */
+    0,					/* tp_clear */
+    0,					/* tp_richcompare */
+    offsetof(PatternObject, weakreflist),	/* tp_weaklistoffset */
+};
+
+static int _validate(PatternObject *self); /* Forward */
+
+static PyObject *
+_compile(PyObject* self_, PyObject* args)
+{
+    /* "compile" pattern descriptor to pattern object */
+
+    PatternObject* self;
+    Py_ssize_t i, n;
+
+    PyObject* pattern;
+    int flags = 0;
+    PyObject* code;
+    Py_ssize_t groups = 0;
+    PyObject* groupindex = NULL;
+    PyObject* indexgroup = NULL;
+    if (!PyArg_ParseTuple(args, "OiO!|nOO", &pattern, &flags,
+                          &PyList_Type, &code, &groups,
+                          &groupindex, &indexgroup))
+        return NULL;
+
+    n = PyList_GET_SIZE(code);
+    /* coverity[ampersand_in_size] */
+    self = PyObject_NEW_VAR(PatternObject, &Pattern_Type, n);
+    if (!self)
+        return NULL;
+
+    self->codesize = n;
+
+    for (i = 0; i < n; i++) {
+        PyObject *o = PyList_GET_ITEM(code, i);
+        unsigned long value = PyInt_Check(o) ? (unsigned long)PyInt_AsLong(o)
+                                              : PyLong_AsUnsignedLong(o);
+        self->code[i] = (SRE_CODE) value;
+        if ((unsigned long) self->code[i] != value) {
+            PyErr_SetString(PyExc_OverflowError,
+                            "regular expression code size limit exceeded");
+            break;
+        }
+    }
+
+    if (PyErr_Occurred()) {
+        PyObject_DEL(self);
+        return NULL;
+    }
+
+    Py_INCREF(pattern);
+    self->pattern = pattern;
+
+    self->flags = flags;
+
+    self->groups = groups;
+
+    Py_XINCREF(groupindex);
+    self->groupindex = groupindex;
+
+    Py_XINCREF(indexgroup);
+    self->indexgroup = indexgroup;
+
+    self->weakreflist = NULL;
+
+    if (!_validate(self)) {
+        Py_DECREF(self);
+        return NULL;
+    }
+
+    return (PyObject*) self;
+}
+
+/* -------------------------------------------------------------------- */
+/* Code validation */
+
+/* To learn more about this code, have a look at the _compile() function in
+   Lib/sre_compile.py.  The validation functions below checks the code array
+   for conformance with the code patterns generated there.
+
+   The nice thing about the generated code is that it is position-independent:
+   all jumps are relative jumps forward.  Also, jumps don't cross each other:
+   the target of a later jump is always earlier than the target of an earlier
+   jump.  IOW, this is okay:
+
+   J---------J-------T--------T
+    \         \_____/        /
+     \______________________/
+
+   but this is not:
+
+   J---------J-------T--------T
+    \_________\_____/        /
+               \____________/
+
+   It also helps that SRE_CODE is always an unsigned type, either 2 bytes or 4
+   bytes wide (the latter if Python is compiled for "wide" unicode support).
+*/
+
+/* Defining this one enables tracing of the validator */
+#undef VVERBOSE
+
+/* Trace macro for the validator */
+#if defined(VVERBOSE)
+#define VTRACE(v) printf v
+#else
+#define VTRACE(v)
+#endif
+
+/* Report failure */
+#define FAIL do { VTRACE(("FAIL: %d\n", __LINE__)); return 0; } while (0)
+
+/* Extract opcode, argument, or skip count from code array */
+#define GET_OP                                          \
+    do {                                                \
+        VTRACE(("%p: ", code));                         \
+        if (code >= end) FAIL;                          \
+        op = *code++;                                   \
+        VTRACE(("%lu (op)\n", (unsigned long)op));      \
+    } while (0)
+#define GET_ARG                                         \
+    do {                                                \
+        VTRACE(("%p= ", code));                         \
+        if (code >= end) FAIL;                          \
+        arg = *code++;                                  \
+        VTRACE(("%lu (arg)\n", (unsigned long)arg));    \
+    } while (0)
+#define GET_SKIP_ADJ(adj)                               \
+    do {                                                \
+        VTRACE(("%p= ", code));                         \
+        if (code >= end) FAIL;                          \
+        skip = *code;                                   \
+        VTRACE(("%lu (skip to %p)\n",                   \
+               (unsigned long)skip, code+skip));        \
+        if (code+skip-adj < code || code+skip-adj > end)\
+            FAIL;                                       \
+        code++;                                         \
+    } while (0)
+#define GET_SKIP GET_SKIP_ADJ(0)
+
+static int
+_validate_charset(SRE_CODE *code, SRE_CODE *end)
+{
+    /* Some variables are manipulated by the macros above */
+    SRE_CODE op;
+    SRE_CODE arg;
+    SRE_CODE offset;
+    int i;
+
+    while (code < end) {
+        GET_OP;
+        switch (op) {
+
+        case SRE_OP_NEGATE:
+            break;
+
+        case SRE_OP_LITERAL:
+            GET_ARG;
+            break;
+
+        case SRE_OP_RANGE:
+            GET_ARG;
+            GET_ARG;
+            break;
+
+        case SRE_OP_CHARSET:
+            offset = 32/sizeof(SRE_CODE); /* 32-byte bitmap */
+            if (code+offset < code || code+offset > end)
+                FAIL;
+            code += offset;
+            break;
+
+        case SRE_OP_BIGCHARSET:
+            GET_ARG; /* Number of blocks */
+            offset = 256/sizeof(SRE_CODE); /* 256-byte table */
+            if (code+offset < code || code+offset > end)
+                FAIL;
+            /* Make sure that each byte points to a valid block */
+            for (i = 0; i < 256; i++) {
+                if (((unsigned char *)code)[i] >= arg)
+                    FAIL;
+            }
+            code += offset;
+            offset = arg * 32/sizeof(SRE_CODE); /* 32-byte bitmap times arg */
+            if (code+offset < code || code+offset > end)
+                FAIL;
+            code += offset;
+            break;
+
+        case SRE_OP_CATEGORY:
+            GET_ARG;
+            switch (arg) {
+            case SRE_CATEGORY_DIGIT:
+            case SRE_CATEGORY_NOT_DIGIT:
+            case SRE_CATEGORY_SPACE:
+            case SRE_CATEGORY_NOT_SPACE:
+            case SRE_CATEGORY_WORD:
+            case SRE_CATEGORY_NOT_WORD:
+            case SRE_CATEGORY_LINEBREAK:
+            case SRE_CATEGORY_NOT_LINEBREAK:
+            case SRE_CATEGORY_LOC_WORD:
+            case SRE_CATEGORY_LOC_NOT_WORD:
+            case SRE_CATEGORY_UNI_DIGIT:
+            case SRE_CATEGORY_UNI_NOT_DIGIT:
+            case SRE_CATEGORY_UNI_SPACE:
+            case SRE_CATEGORY_UNI_NOT_SPACE:
+            case SRE_CATEGORY_UNI_WORD:
+            case SRE_CATEGORY_UNI_NOT_WORD:
+            case SRE_CATEGORY_UNI_LINEBREAK:
+            case SRE_CATEGORY_UNI_NOT_LINEBREAK:
+                break;
+            default:
+                FAIL;
+            }
+            break;
+
+        default:
+            FAIL;
+
+        }
+    }
+
+    return 1;
+}
+
+static int
+_validate_inner(SRE_CODE *code, SRE_CODE *end, Py_ssize_t groups)
+{
+    /* Some variables are manipulated by the macros above */
+    SRE_CODE op;
+    SRE_CODE arg;
+    SRE_CODE skip;
+
+    VTRACE(("code=%p, end=%p\n", code, end));
+
+    if (code > end)
+        FAIL;
+
+    while (code < end) {
+        GET_OP;
+        switch (op) {
+
+        case SRE_OP_MARK:
+            /* We don't check whether marks are properly nested; the
+               sre_match() code is robust even if they don't, and the worst
+               you can get is nonsensical match results. */
+            GET_ARG;
+            if (arg > 2*groups+1) {
+                VTRACE(("arg=%d, groups=%d\n", (int)arg, (int)groups));
+                FAIL;
+            }
+            break;
+
+        case SRE_OP_LITERAL:
+        case SRE_OP_NOT_LITERAL:
+        case SRE_OP_LITERAL_IGNORE:
+        case SRE_OP_NOT_LITERAL_IGNORE:
+            GET_ARG;
+            /* The arg is just a character, nothing to check */
+            break;
+
+        case SRE_OP_SUCCESS:
+        case SRE_OP_FAILURE:
+            /* Nothing to check; these normally end the matching process */
+            break;
+
+        case SRE_OP_AT:
+            GET_ARG;
+            switch (arg) {
+            case SRE_AT_BEGINNING:
+            case SRE_AT_BEGINNING_STRING:
+            case SRE_AT_BEGINNING_LINE:
+            case SRE_AT_END:
+            case SRE_AT_END_LINE:
+            case SRE_AT_END_STRING:
+            case SRE_AT_BOUNDARY:
+            case SRE_AT_NON_BOUNDARY:
+            case SRE_AT_LOC_BOUNDARY:
+            case SRE_AT_LOC_NON_BOUNDARY:
+            case SRE_AT_UNI_BOUNDARY:
+            case SRE_AT_UNI_NON_BOUNDARY:
+                break;
+            default:
+                FAIL;
+            }
+            break;
+
+        case SRE_OP_ANY:
+        case SRE_OP_ANY_ALL:
+            /* These have no operands */
+            break;
+
+        case SRE_OP_IN:
+        case SRE_OP_IN_IGNORE:
+            GET_SKIP;
+            /* Stop 1 before the end; we check the FAILURE below */
+            if (!_validate_charset(code, code+skip-2))
+                FAIL;
+            if (code[skip-2] != SRE_OP_FAILURE)
+                FAIL;
+            code += skip-1;
+            break;
+
+        case SRE_OP_INFO:
+            {
+                /* A minimal info field is
+                   <INFO> <1=skip> <2=flags> <3=min> <4=max>;
+                   If SRE_INFO_PREFIX or SRE_INFO_CHARSET is in the flags,
+                   more follows. */
+                SRE_CODE flags, min, max, i;
+                SRE_CODE *newcode;
+                GET_SKIP;
+                newcode = code+skip-1;
+                GET_ARG; flags = arg;
+                GET_ARG; min = arg;
+                GET_ARG; max = arg;
+                /* Check that only valid flags are present */
+                if ((flags & ~(SRE_INFO_PREFIX |
+                               SRE_INFO_LITERAL |
+                               SRE_INFO_CHARSET)) != 0)
+                    FAIL;
+                /* PREFIX and CHARSET are mutually exclusive */
+                if ((flags & SRE_INFO_PREFIX) &&
+                    (flags & SRE_INFO_CHARSET))
+                    FAIL;
+                /* LITERAL implies PREFIX */
+                if ((flags & SRE_INFO_LITERAL) &&
+                    !(flags & SRE_INFO_PREFIX))
+                    FAIL;
+                /* Validate the prefix */
+                if (flags & SRE_INFO_PREFIX) {
+                    SRE_CODE prefix_len, prefix_skip;
+                    GET_ARG; prefix_len = arg;
+                    GET_ARG; prefix_skip = arg;
+                    /* Here comes the prefix string */
+                    if (code+prefix_len < code || code+prefix_len > newcode)
+                        FAIL;
+                    code += prefix_len;
+                    /* And here comes the overlap table */
+                    if (code+prefix_len < code || code+prefix_len > newcode)
+                        FAIL;
+                    /* Each overlap value should be < prefix_len */
+                    for (i = 0; i < prefix_len; i++) {
+                        if (code[i] >= prefix_len)
+                            FAIL;
+                    }
+                    code += prefix_len;
+                }
+                /* Validate the charset */
+                if (flags & SRE_INFO_CHARSET) {
+                    if (!_validate_charset(code, newcode-1))
+                        FAIL;
+                    if (newcode[-1] != SRE_OP_FAILURE)
+                        FAIL;
+                    code = newcode;
+                }
+                else if (code != newcode) {
+                  VTRACE(("code=%p, newcode=%p\n", code, newcode));
+                    FAIL;
+                }
+            }
+            break;
+
+        case SRE_OP_BRANCH:
+            {
+                SRE_CODE *target = NULL;
+                for (;;) {
+                    GET_SKIP;
+                    if (skip == 0)
+                        break;
+                    /* Stop 2 before the end; we check the JUMP below */
+                    if (!_validate_inner(code, code+skip-3, groups))
+                        FAIL;
+                    code += skip-3;
+                    /* Check that it ends with a JUMP, and that each JUMP
+                       has the same target */
+                    GET_OP;
+                    if (op != SRE_OP_JUMP)
+                        FAIL;
+                    GET_SKIP;
+                    if (target == NULL)
+                        target = code+skip-1;
+                    else if (code+skip-1 != target)
+                        FAIL;
+                }
+            }
+            break;
+
+        case SRE_OP_REPEAT_ONE:
+        case SRE_OP_MIN_REPEAT_ONE:
+            {
+                SRE_CODE min, max;
+                GET_SKIP;
+                GET_ARG; min = arg;
+                GET_ARG; max = arg;
+                if (min > max)
+                    FAIL;
+#ifdef Py_UNICODE_WIDE
+                if (max > 65535)
+                    FAIL;
+#endif
+                if (!_validate_inner(code, code+skip-4, groups))
+                    FAIL;
+                code += skip-4;
+                GET_OP;
+                if (op != SRE_OP_SUCCESS)
+                    FAIL;
+            }
+            break;
+
+        case SRE_OP_REPEAT:
+            {
+                SRE_CODE min, max;
+                GET_SKIP;
+                GET_ARG; min = arg;
+                GET_ARG; max = arg;
+                if (min > max)
+                    FAIL;
+#ifdef Py_UNICODE_WIDE
+                if (max > 65535)
+                    FAIL;
+#endif
+                if (!_validate_inner(code, code+skip-3, groups))
+                    FAIL;
+                code += skip-3;
+                GET_OP;
+                if (op != SRE_OP_MAX_UNTIL && op != SRE_OP_MIN_UNTIL)
+                    FAIL;
+            }
+            break;
+
+        case SRE_OP_GROUPREF:
+        case SRE_OP_GROUPREF_IGNORE:
+            GET_ARG;
+            if (arg >= groups)
+                FAIL;
+            break;
+
+        case SRE_OP_GROUPREF_EXISTS:
+            /* The regex syntax for this is: '(?(group)then|else)', where
+               'group' is either an integer group number or a group name,
+               'then' and 'else' are sub-regexes, and 'else' is optional. */
+            GET_ARG;
+            if (arg >= groups)
+                FAIL;
+            GET_SKIP_ADJ(1);
+            code--; /* The skip is relative to the first arg! */
+            /* There are two possibilities here: if there is both a 'then'
+               part and an 'else' part, the generated code looks like:
+
+               GROUPREF_EXISTS
+               <group>
+               <skipyes>
+               ...then part...
+               JUMP
+               <skipno>
+               (<skipyes> jumps here)
+               ...else part...
+               (<skipno> jumps here)
+
+               If there is only a 'then' part, it looks like:
+
+               GROUPREF_EXISTS
+               <group>
+               <skip>
+               ...then part...
+               (<skip> jumps here)
+
+               There is no direct way to decide which it is, and we don't want
+               to allow arbitrary jumps anywhere in the code; so we just look
+               for a JUMP opcode preceding our skip target.
+            */
+            if (skip >= 3 && code+skip-3 >= code &&
+                code[skip-3] == SRE_OP_JUMP)
+            {
+                VTRACE(("both then and else parts present\n"));
+                if (!_validate_inner(code+1, code+skip-3, groups))
+                    FAIL;
+                code += skip-2; /* Position after JUMP, at <skipno> */
+                GET_SKIP;
+                if (!_validate_inner(code, code+skip-1, groups))
+                    FAIL;
+                code += skip-1;
+            }
+            else {
+                VTRACE(("only a then part present\n"));
+                if (!_validate_inner(code+1, code+skip-1, groups))
+                    FAIL;
+                code += skip-1;
+            }
+            break;
+
+        case SRE_OP_ASSERT:
+        case SRE_OP_ASSERT_NOT:
+            GET_SKIP;
+            GET_ARG; /* 0 for lookahead, width for lookbehind */
+            code--; /* Back up over arg to simplify math below */
+            if (arg & 0x80000000)
+                FAIL; /* Width too large */
+            /* Stop 1 before the end; we check the SUCCESS below */
+            if (!_validate_inner(code+1, code+skip-2, groups))
+                FAIL;
+            code += skip-2;
+            GET_OP;
+            if (op != SRE_OP_SUCCESS)
+                FAIL;
+            break;
+
+        default:
+            FAIL;
+
+        }
+    }
+
+    VTRACE(("okay\n"));
+    return 1;
+}
+
+static int
+_validate_outer(SRE_CODE *code, SRE_CODE *end, Py_ssize_t groups)
+{
+    if (groups < 0 || groups > 100 || code >= end || end[-1] != SRE_OP_SUCCESS)
+        FAIL;
+    if (groups == 0)  /* fix for simplejson */
+        groups = 100; /* 100 groups should always be safe */
+    return _validate_inner(code, end-1, groups);
+}
+
+static int
+_validate(PatternObject *self)
+{
+    if (!_validate_outer(self->code, self->code+self->codesize, self->groups))
+    {
+        PyErr_SetString(PyExc_RuntimeError, "invalid SRE code");
+        return 0;
+    }
+    else
+        VTRACE(("Success!\n"));
+    return 1;
+}
+
+/* -------------------------------------------------------------------- */
+/* match methods */
+
+static void
+match_dealloc(MatchObject* self)
+{
+    Py_XDECREF(self->regs);
+    Py_XDECREF(self->string);
+    Py_DECREF(self->pattern);
+    PyObject_DEL(self);
+}
+
+static PyObject*
+match_getslice_by_index(MatchObject* self, Py_ssize_t index, PyObject* def)
+{
+    if (index < 0 || index >= self->groups) {
+        /* raise IndexError if we were given a bad group number */
+        PyErr_SetString(
+            PyExc_IndexError,
+            "no such group"
+            );
+        return NULL;
+    }
+
+    index *= 2;
+
+    if (self->string == Py_None || self->mark[index] < 0) {
+        /* return default value if the string or group is undefined */
+        Py_INCREF(def);
+        return def;
+    }
+
+    return PySequence_GetSlice(
+        self->string, self->mark[index], self->mark[index+1]
+        );
+}
+
+static Py_ssize_t
+match_getindex(MatchObject* self, PyObject* index)
+{
+    Py_ssize_t i;
+
+    if (PyInt_Check(index))
+        return PyInt_AsSsize_t(index);
+
+    i = -1;
+
+    if (self->pattern->groupindex) {
+        index = PyObject_GetItem(self->pattern->groupindex, index);
+        if (index) {
+            if (PyInt_Check(index) || PyLong_Check(index))
+                i = PyInt_AsSsize_t(index);
+            Py_DECREF(index);
+        } else
+            PyErr_Clear();
+    }
+
+    return i;
+}
+
+static PyObject*
+match_getslice(MatchObject* self, PyObject* index, PyObject* def)
+{
+    return match_getslice_by_index(self, match_getindex(self, index), def);
+}
+
+static PyObject*
+match_expand(MatchObject* self, PyObject* ptemplate)
+{
+    /* delegate to Python code */
+    return call(
+        SRE_PY_MODULE, "_expand",
+        PyTuple_Pack(3, self->pattern, self, ptemplate)
+        );
+}
+
+static PyObject*
+match_group(MatchObject* self, PyObject* args)
+{
+    PyObject* result;
+    Py_ssize_t i, size;
+
+    size = PyTuple_GET_SIZE(args);
+
+    switch (size) {
+    case 0:
+        result = match_getslice(self, Py_False, Py_None);
+        break;
+    case 1:
+        result = match_getslice(self, PyTuple_GET_ITEM(args, 0), Py_None);
+        break;
+    default:
+        /* fetch multiple items */
+        result = PyTuple_New(size);
+        if (!result)
+            return NULL;
+        for (i = 0; i < size; i++) {
+            PyObject* item = match_getslice(
+                self, PyTuple_GET_ITEM(args, i), Py_None
+                );
+            if (!item) {
+                Py_DECREF(result);
+                return NULL;
+            }
+            PyTuple_SET_ITEM(result, i, item);
+        }
+        break;
+    }
+    return result;
+}
+
+static PyObject*
+match_groups(MatchObject* self, PyObject* args, PyObject* kw)
+{
+    PyObject* result;
+    Py_ssize_t index;
+
+    PyObject* def = Py_None;
+    static char* kwlist[] = { "default", NULL };
+    if (!PyArg_ParseTupleAndKeywords(args, kw, "|O:groups", kwlist, &def))
+        return NULL;
+
+    result = PyTuple_New(self->groups-1);
+    if (!result)
+        return NULL;
+
+    for (index = 1; index < self->groups; index++) {
+        PyObject* item;
+        item = match_getslice_by_index(self, index, def);
+        if (!item) {
+            Py_DECREF(result);
+            return NULL;
+        }
+        PyTuple_SET_ITEM(result, index-1, item);
+    }
+
+    return result;
+}
+
+static PyObject*
+match_groupdict(MatchObject* self, PyObject* args, PyObject* kw)
+{
+    PyObject* result;
+    PyObject* keys;
+    Py_ssize_t index;
+
+    PyObject* def = Py_None;
+    static char* kwlist[] = { "default", NULL };
+    if (!PyArg_ParseTupleAndKeywords(args, kw, "|O:groupdict", kwlist, &def))
+        return NULL;
+
+    result = PyDict_New();
+    if (!result || !self->pattern->groupindex)
+        return result;
+
+    keys = PyMapping_Keys(self->pattern->groupindex);
+    if (!keys)
+        goto failed;
+
+    for (index = 0; index < PyList_GET_SIZE(keys); index++) {
+        int status;
+        PyObject* key;
+        PyObject* value;
+        key = PyList_GET_ITEM(keys, index);
+        if (!key)
+            goto failed;
+        value = match_getslice(self, key, def);
+        if (!value) {
+            Py_DECREF(key);
+            goto failed;
+        }
+        status = PyDict_SetItem(result, key, value);
+        Py_DECREF(value);
+        if (status < 0)
+            goto failed;
+    }
+
+    Py_DECREF(keys);
+
+    return result;
+
+failed:
+    Py_XDECREF(keys);
+    Py_DECREF(result);
+    return NULL;
+}
+
+static PyObject*
+match_start(MatchObject* self, PyObject* args)
+{
+    Py_ssize_t index;
+
+    PyObject* index_ = Py_False; /* zero */
+    if (!PyArg_UnpackTuple(args, "start", 0, 1, &index_))
+        return NULL;
+
+    index = match_getindex(self, index_);
+
+    if (index < 0 || index >= self->groups) {
+        PyErr_SetString(
+            PyExc_IndexError,
+            "no such group"
+            );
+        return NULL;
+    }
+
+    /* mark is -1 if group is undefined */
+    return Py_BuildValue("i", self->mark[index*2]);
+}
+
+static PyObject*
+match_end(MatchObject* self, PyObject* args)
+{
+    Py_ssize_t index;
+
+    PyObject* index_ = Py_False; /* zero */
+    if (!PyArg_UnpackTuple(args, "end", 0, 1, &index_))
+        return NULL;
+
+    index = match_getindex(self, index_);
+
+    if (index < 0 || index >= self->groups) {
+        PyErr_SetString(
+            PyExc_IndexError,
+            "no such group"
+            );
+        return NULL;
+    }
+
+    /* mark is -1 if group is undefined */
+    return Py_BuildValue("i", self->mark[index*2+1]);
+}
+
+LOCAL(PyObject*)
+_pair(Py_ssize_t i1, Py_ssize_t i2)
+{
+    PyObject* pair;
+    PyObject* item;
+
+    pair = PyTuple_New(2);
+    if (!pair)
+        return NULL;
+
+    item = PyInt_FromSsize_t(i1);
+    if (!item)
+        goto error;
+    PyTuple_SET_ITEM(pair, 0, item);
+
+    item = PyInt_FromSsize_t(i2);
+    if (!item)
+        goto error;
+    PyTuple_SET_ITEM(pair, 1, item);
+
+    return pair;
+
+  error:
+    Py_DECREF(pair);
+    return NULL;
+}
+
+static PyObject*
+match_span(MatchObject* self, PyObject* args)
+{
+    Py_ssize_t index;
+
+    PyObject* index_ = Py_False; /* zero */
+    if (!PyArg_UnpackTuple(args, "span", 0, 1, &index_))
+        return NULL;
+
+    index = match_getindex(self, index_);
+
+    if (index < 0 || index >= self->groups) {
+        PyErr_SetString(
+            PyExc_IndexError,
+            "no such group"
+            );
+        return NULL;
+    }
+
+    /* marks are -1 if group is undefined */
+    return _pair(self->mark[index*2], self->mark[index*2+1]);
+}
+
+static PyObject*
+match_regs(MatchObject* self)
+{
+    PyObject* regs;
+    PyObject* item;
+    Py_ssize_t index;
+
+    regs = PyTuple_New(self->groups);
+    if (!regs)
+        return NULL;
+
+    for (index = 0; index < self->groups; index++) {
+        item = _pair(self->mark[index*2], self->mark[index*2+1]);
+        if (!item) {
+            Py_DECREF(regs);
+            return NULL;
+        }
+        PyTuple_SET_ITEM(regs, index, item);
+    }
+
+    Py_INCREF(regs);
+    self->regs = regs;
+
+    return regs;
+}
+
+static PyObject*
+match_copy(MatchObject* self, PyObject *unused)
+{
+#ifdef USE_BUILTIN_COPY
+    MatchObject* copy;
+    Py_ssize_t slots, offset;
+
+    slots = 2 * (self->pattern->groups+1);
+
+    copy = PyObject_NEW_VAR(MatchObject, &Match_Type, slots);
+    if (!copy)
+        return NULL;
+
+    /* this value a constant, but any compiler should be able to
+       figure that out all by itself */
+    offset = offsetof(MatchObject, string);
+
+    Py_XINCREF(self->pattern);
+    Py_XINCREF(self->string);
+    Py_XINCREF(self->regs);
+
+    memcpy((char*) copy + offset, (char*) self + offset,
+           sizeof(MatchObject) + slots * sizeof(Py_ssize_t) - offset);
+
+    return (PyObject*) copy;
+#else
+    PyErr_SetString(PyExc_TypeError, "cannot copy this match object");
+    return NULL;
+#endif
+}
+
+static PyObject*
+match_deepcopy(MatchObject* self, PyObject* memo)
+{
+#ifdef USE_BUILTIN_COPY
+    MatchObject* copy;
+
+    copy = (MatchObject*) match_copy(self);
+    if (!copy)
+        return NULL;
+
+    if (!deepcopy((PyObject**) &copy->pattern, memo) ||
+        !deepcopy(&copy->string, memo) ||
+        !deepcopy(&copy->regs, memo)) {
+        Py_DECREF(copy);
+        return NULL;
+    }
+
+#else
+    PyErr_SetString(PyExc_TypeError, "cannot deepcopy this match object");
+    return NULL;
+#endif
+}
+
+static PyMethodDef match_methods[] = {
+    {"group", (PyCFunction) match_group, METH_VARARGS},
+    {"start", (PyCFunction) match_start, METH_VARARGS},
+    {"end", (PyCFunction) match_end, METH_VARARGS},
+    {"span", (PyCFunction) match_span, METH_VARARGS},
+    {"groups", (PyCFunction) match_groups, METH_VARARGS|METH_KEYWORDS},
+    {"groupdict", (PyCFunction) match_groupdict, METH_VARARGS|METH_KEYWORDS},
+    {"expand", (PyCFunction) match_expand, METH_O},
+    {"__copy__", (PyCFunction) match_copy, METH_NOARGS},
+    {"__deepcopy__", (PyCFunction) match_deepcopy, METH_O},
+    {NULL, NULL}
+};
+
+static PyObject*
+match_getattr(MatchObject* self, char* name)
+{
+    PyObject* res;
+
+    res = Py_FindMethod(match_methods, (PyObject*) self, name);
+    if (res)
+        return res;
+
+    PyErr_Clear();
+
+    if (!strcmp(name, "lastindex")) {
+        if (self->lastindex >= 0)
+            return Py_BuildValue("i", self->lastindex);
+        Py_INCREF(Py_None);
+        return Py_None;
+    }
+
+    if (!strcmp(name, "lastgroup")) {
+        if (self->pattern->indexgroup && self->lastindex >= 0) {
+            PyObject* result = PySequence_GetItem(
+                self->pattern->indexgroup, self->lastindex
+                );
+            if (result)
+                return result;
+            PyErr_Clear();
+        }
+        Py_INCREF(Py_None);
+        return Py_None;
+    }
+
+    if (!strcmp(name, "string")) {
+        if (self->string) {
+            Py_INCREF(self->string);
+            return self->string;
+        } else {
+            Py_INCREF(Py_None);
+            return Py_None;
+        }
+    }
+
+    if (!strcmp(name, "regs")) {
+        if (self->regs) {
+            Py_INCREF(self->regs);
+            return self->regs;
+        } else
+            return match_regs(self);
+    }
+
+    if (!strcmp(name, "re")) {
+        Py_INCREF(self->pattern);
+        return (PyObject*) self->pattern;
+    }
+
+    if (!strcmp(name, "pos"))
+        return Py_BuildValue("i", self->pos);
+
+    if (!strcmp(name, "endpos"))
+        return Py_BuildValue("i", self->endpos);
+
+    PyErr_SetString(PyExc_AttributeError, name);
+    return NULL;
+}
+
+/* FIXME: implement setattr("string", None) as a special case (to
+   detach the associated string, if any */
+
+statichere PyTypeObject Match_Type = {
+    PyObject_HEAD_INIT(NULL)
+    0, "_" SRE_MODULE ".SRE_Match",
+    sizeof(MatchObject), sizeof(Py_ssize_t),
+    (destructor)match_dealloc, /*tp_dealloc*/
+    0, /*tp_print*/
+    (getattrfunc)match_getattr /*tp_getattr*/
+};
+
+static PyObject*
+pattern_new_match(PatternObject* pattern, SRE_STATE* state, int status)
+{
+    /* create match object (from state object) */
+
+    MatchObject* match;
+    Py_ssize_t i, j;
+    char* base;
+    int n;
+
+    if (status > 0) {
+
+        /* create match object (with room for extra group marks) */
+        /* coverity[ampersand_in_size] */
+        match = PyObject_NEW_VAR(MatchObject, &Match_Type,
+                                 2*(pattern->groups+1));
+        if (!match)
+            return NULL;
+
+        Py_INCREF(pattern);
+        match->pattern = pattern;
+
+        Py_INCREF(state->string);
+        match->string = state->string;
+
+        match->regs = NULL;
+        match->groups = pattern->groups+1;
+
+        /* fill in group slices */
+
+        base = (char*) state->beginning;
+        n = state->charsize;
+
+        match->mark[0] = ((char*) state->start - base) / n;
+        match->mark[1] = ((char*) state->ptr - base) / n;
+
+        for (i = j = 0; i < pattern->groups; i++, j+=2)
+            if (j+1 <= state->lastmark && state->mark[j] && state->mark[j+1]) {
+                match->mark[j+2] = ((char*) state->mark[j] - base) / n;
+                match->mark[j+3] = ((char*) state->mark[j+1] - base) / n;
+            } else
+                match->mark[j+2] = match->mark[j+3] = -1; /* undefined */
+
+        match->pos = state->pos;
+        match->endpos = state->endpos;
+
+        match->lastindex = state->lastindex;
+
+        return (PyObject*) match;
+
+    } else if (status == 0) {
+
+        /* no match */
+        Py_INCREF(Py_None);
+        return Py_None;
+
+    }
+
+    /* internal error */
+    pattern_error(status);
+    return NULL;
+}
+
+
+/* -------------------------------------------------------------------- */
+/* scanner methods (experimental) */
+
+static void
+scanner_dealloc(ScannerObject* self)
+{
+    state_fini(&self->state);
+    Py_DECREF(self->pattern);
+    PyObject_DEL(self);
+}
+
+static PyObject*
+scanner_match(ScannerObject* self, PyObject *unused)
+{
+    SRE_STATE* state = &self->state;
+    PyObject* match;
+    int status;
+
+    state_reset(state);
+
+    state->ptr = state->start;
+
+    if (state->charsize == 1) {
+        status = sre_match(state, PatternObject_GetCode(self->pattern));
+    } else {
+#if defined(HAVE_UNICODE)
+        status = sre_umatch(state, PatternObject_GetCode(self->pattern));
+#endif
+    }
+    if (PyErr_Occurred())
+        return NULL;
+
+    match = pattern_new_match((PatternObject*) self->pattern,
+                               state, status);
+
+    if (status == 0 || state->ptr == state->start)
+        state->start = (void*) ((char*) state->ptr + state->charsize);
+    else
+        state->start = state->ptr;
+
+    return match;
+}
+
+
+static PyObject*
+scanner_search(ScannerObject* self, PyObject *unused)
+{
+    SRE_STATE* state = &self->state;
+    PyObject* match;
+    int status;
+
+    state_reset(state);
+
+    state->ptr = state->start;
+
+    if (state->charsize == 1) {
+        status = sre_search(state, PatternObject_GetCode(self->pattern));
+    } else {
+#if defined(HAVE_UNICODE)
+        status = sre_usearch(state, PatternObject_GetCode(self->pattern));
+#endif
+    }
+    if (PyErr_Occurred())
+        return NULL;
+
+    match = pattern_new_match((PatternObject*) self->pattern,
+                               state, status);
+
+    if (status == 0 || state->ptr == state->start)
+        state->start = (void*) ((char*) state->ptr + state->charsize);
+    else
+        state->start = state->ptr;
+
+    return match;
+}
+
+static PyMethodDef scanner_methods[] = {
+    {"match", (PyCFunction) scanner_match, METH_NOARGS},
+    {"search", (PyCFunction) scanner_search, METH_NOARGS},
+    {NULL, NULL}
+};
+
+static PyObject*
+scanner_getattr(ScannerObject* self, char* name)
+{
+    PyObject* res;
+
+    res = Py_FindMethod(scanner_methods, (PyObject*) self, name);
+    if (res)
+        return res;
+
+    PyErr_Clear();
+
+    /* attributes */
+    if (!strcmp(name, "pattern")) {
+        Py_INCREF(self->pattern);
+        return self->pattern;
+    }
+
+    PyErr_SetString(PyExc_AttributeError, name);
+    return NULL;
+}
+
+statichere PyTypeObject Scanner_Type = {
+    PyObject_HEAD_INIT(NULL)
+    0, "_" SRE_MODULE ".SRE_Scanner",
+    sizeof(ScannerObject), 0,
+    (destructor)scanner_dealloc, /*tp_dealloc*/
+    0, /*tp_print*/
+    (getattrfunc)scanner_getattr, /*tp_getattr*/
+};
+
+static PyObject*
+pattern_scanner(PatternObject* pattern, PyObject* args)
+{
+    /* create search state object */
+
+    ScannerObject* self;
+
+    PyObject* string;
+    Py_ssize_t start = 0;
+    Py_ssize_t end = PY_SSIZE_T_MAX;
+    if (!PyArg_ParseTuple(args, "O|nn:scanner", &string, &start, &end))
+        return NULL;
+
+    /* create scanner object */
+    self = PyObject_NEW(ScannerObject, &Scanner_Type);
+    if (!self)
+        return NULL;
+
+    string = state_init(&self->state, pattern, string, start, end);
+    if (!string) {
+        PyObject_DEL(self);
+        return NULL;
+    }
+
+    Py_INCREF(pattern);
+    self->pattern = (PyObject*) pattern;
+
+    return (PyObject*) self;
+}
+
+static PyMethodDef _functions[] = {
+    {"compile", _compile, METH_VARARGS},
+    {"getcodesize", sre_codesize, METH_NOARGS},
+    {"getlower", sre_getlower, METH_VARARGS},
+    {NULL, NULL}
+};
+
+#if PY_VERSION_HEX < 0x02030000
+DL_EXPORT(void) init_sre(void)
+#else
+PyMODINIT_FUNC init_sre(void)
+#endif
+{
+    PyObject* m;
+    PyObject* d;
+    PyObject* x;
+
+    /* Patch object types */
+    Pattern_Type.ob_type = Match_Type.ob_type =
+        Scanner_Type.ob_type = &PyType_Type;
+
+    m = Py_InitModule("_" SRE_MODULE, _functions);
+    if (m == NULL)
+    	return;
+    d = PyModule_GetDict(m);
+
+    x = PyInt_FromLong(SRE_MAGIC);
+    if (x) {
+        PyDict_SetItemString(d, "MAGIC", x);
+        Py_DECREF(x);
+    }
+
+    x = PyInt_FromLong(sizeof(SRE_CODE));
+    if (x) {
+        PyDict_SetItemString(d, "CODESIZE", x);
+        Py_DECREF(x);
+    }
+
+    x = PyString_FromString(copyright);
+    if (x) {
+        PyDict_SetItemString(d, "copyright", x);
+        Py_DECREF(x);
+    }
+}
+
+#endif /* !defined(SRE_RECURSIVE) */
+
+/* vim:ts=4:sw=4:et
+*/