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/*
* 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.
*/
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"
#define SRE_CODE_BITS (8 * sizeof(SRE_CODE))
#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
/* -------------------------------------------------------------------- */
/* optional features */
/* enables fast searching */
#define USE_FAST_SEARCH
/* enables copy/deepcopy handling (work in progress) */
#undef USE_BUILTIN_COPY
/* -------------------------------------------------------------------- */
#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_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 */
#define SRE_UNI_IS_DIGIT(ch) Py_UNICODE_ISDECIMAL(ch)
#define SRE_UNI_IS_SPACE(ch) Py_UNICODE_ISSPACE(ch)
#define SRE_UNI_IS_LINEBREAK(ch) Py_UNICODE_ISLINEBREAK(ch)
#define SRE_UNI_IS_ALNUM(ch) Py_UNICODE_ISALNUM(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(ch);
}
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);
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);
}
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 %" PY_FORMAT_SIZE_T "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 Py_UCS1
#define SIZEOF_SRE_CHAR 1
#define SRE(F) sre_ucs1_##F
#include "sre_lib.h"
/* generate 16-bit unicode version */
#define SRE_CHAR Py_UCS2
#define SIZEOF_SRE_CHAR 2
#define SRE(F) sre_ucs2_##F
#include "sre_lib.h"
/* generate 32-bit unicode version */
#define SRE_CHAR Py_UCS4
#define SIZEOF_SRE_CHAR 4
#define SRE(F) sre_ucs4_##F
#include "sre_lib.h"
/* -------------------------------------------------------------------- */
/* factories and destructors */
/* see sre.h for object declarations */
static PyObject*pattern_new_match(PatternObject*, SRE_STATE*, int);
static PyObject*pattern_scanner(PatternObject*, PyObject*, PyObject* kw);
static PyObject *
sre_codesize(PyObject* self, PyObject *unused)
{
return PyLong_FromSize_t(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)
return Py_BuildValue("i", sre_lower_unicode(character));
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_isbytes, int* p_charsize,
Py_buffer *view)
{
/* 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) */
/* Unicode objects do not support the buffer API. So, get the data
directly instead. */
if (PyUnicode_Check(string)) {
if (PyUnicode_READY(string) == -1)
return NULL;
*p_length = PyUnicode_GET_LENGTH(string);
*p_charsize = PyUnicode_KIND(string);
*p_isbytes = 0;
return PyUnicode_DATA(string);
}
/* get pointer to byte string buffer */
if (PyObject_GetBuffer(string, view, PyBUF_SIMPLE) != 0) {
PyErr_SetString(PyExc_TypeError, "expected string or buffer");
return NULL;
}
*p_length = view->len;
*p_charsize = 1;
*p_isbytes = 1;
if (view->buf == NULL) {
PyErr_SetString(PyExc_ValueError, "Buffer is NULL");
PyBuffer_Release(view);
view->buf = NULL;
return NULL;
}
return view->buf;
}
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 isbytes, charsize;
void* ptr;
memset(state, 0, sizeof(SRE_STATE));
state->lastmark = -1;
state->lastindex = -1;
state->buffer.buf = NULL;
ptr = getstring(string, &length, &isbytes, &charsize, &state->buffer);
if (!ptr)
goto err;
if (isbytes && pattern->isbytes == 0) {
PyErr_SetString(PyExc_TypeError,
"can't use a string pattern on a bytes-like object");
goto err;
}
if (!isbytes && pattern->isbytes > 0) {
PyErr_SetString(PyExc_TypeError,
"can't use a bytes pattern on a string-like object");
goto err;
}
/* 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->isbytes = isbytes;
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)
state->lower = sre_lower_unicode;
else
state->lower = sre_lower;
return string;
err:
if (state->buffer.buf)
PyBuffer_Release(&state->buffer);
return NULL;
}
LOCAL(void)
state_fini(SRE_STATE* state)
{
if (state->buffer.buf)
PyBuffer_Release(&state->buffer);
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*)
getslice(int isbytes, const void *ptr,
PyObject* string, Py_ssize_t start, Py_ssize_t end)
{
if (isbytes) {
if (PyBytes_CheckExact(string) &&
start == 0 && end == PyBytes_GET_SIZE(string)) {
Py_INCREF(string);
return string;
}
return PyBytes_FromStringAndSize(
(const char *)ptr + start, end - start);
}
else {
return PyUnicode_Substring(string, start, end);
}
}
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 getslice(state->isbytes, state->beginning, 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);
}
LOCAL(Py_ssize_t)
sre_match(SRE_STATE* state, SRE_CODE* pattern)
{
if (state->charsize == 1)
return sre_ucs1_match(state, pattern);
if (state->charsize == 2)
return sre_ucs2_match(state, pattern);
assert(state->charsize == 4);
return sre_ucs4_match(state, pattern);
}
LOCAL(Py_ssize_t)
sre_search(SRE_STATE* state, SRE_CODE* pattern)
{
if (state->charsize == 1)
return sre_ucs1_search(state, pattern);
if (state->charsize == 2)
return sre_ucs2_search(state, pattern);
assert(state->charsize == 4);
return sre_ucs4_search(state, pattern);
}
static PyObject*
pattern_match(PatternObject* self, PyObject* args, PyObject* kw)
{
SRE_STATE state;
Py_ssize_t 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));
status = sre_match(&state, PatternObject_GetCode(self));
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));
status = sre_search(&state, PatternObject_GetCode(self));
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 = PyUnicode_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*
pattern_findall(PatternObject* self, PyObject* args, PyObject* kw)
{
SRE_STATE state;
PyObject* list;
Py_ssize_t 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;
status = sre_search(&state, PatternObject_GetCode(self));
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 = getslice(state.isbytes, state.beginning,
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;
}
static PyObject*
pattern_finditer(PatternObject* pattern, PyObject* args, PyObject* kw)
{
PyObject* scanner;
PyObject* search;
PyObject* iterator;
scanner = pattern_scanner(pattern, args, kw);
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;
}
static PyObject*
pattern_split(PatternObject* self, PyObject* args, PyObject* kw)
{
SRE_STATE state;
PyObject* list;
PyObject* item;
Py_ssize_t 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;
status = sre_search(&state, PatternObject_GetCode(self));
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 = getslice(state.isbytes, state.beginning,
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 = getslice(state.isbytes, state.beginning,
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* joiner;
PyObject* item;
PyObject* filter;
PyObject* args;
PyObject* match;
void* ptr;
Py_ssize_t status;
Py_ssize_t n;
Py_ssize_t i, b, e;
int isbytes, charsize;
int filter_is_callable;
Py_buffer view;
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;
view.buf = NULL;
ptr = getstring(ptemplate, &n, &isbytes, &charsize, &view);
b = charsize;
if (ptr) {
if (charsize == 1)
literal = memchr(ptr, '\\', n) == NULL;
else
literal = PyUnicode_FindChar(ptemplate, '\\', 0, n, 1) == -1;
} else {
PyErr_Clear();
literal = 0;
}
if (view.buf)
PyBuffer_Release(&view);
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;
status = sre_search(&state, PatternObject_GetCode(self));
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 = getslice(state.isbytes, state.beginning,
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 = getslice(state.isbytes, state.beginning,
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) */
joiner = getslice(state.isbytes, state.beginning, string, 0, 0);
if (!joiner) {
Py_DECREF(list);
return NULL;
}
if (PyList_GET_SIZE(list) == 0) {
Py_DECREF(list);
item = joiner;
}
else {
if (state.isbytes)
item = _PyBytes_Join(joiner, list);
else
item = PyUnicode_Join(joiner, list);
Py_DECREF(joiner);
Py_DECREF(list);
if (!item)
return NULL;
}
if (subn)
return Py_BuildValue("Nn", 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\
match object 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},
{"finditer", (PyCFunction) pattern_finditer, METH_VARARGS|METH_KEYWORDS,
pattern_finditer_doc},
{"scanner", (PyCFunction) pattern_scanner, METH_VARARGS|METH_KEYWORDS},
{"__copy__", (PyCFunction) pattern_copy, METH_NOARGS},
{"__deepcopy__", (PyCFunction) pattern_deepcopy, METH_O},
{NULL, NULL}
};
#define PAT_OFF(x) offsetof(PatternObject, x)
static PyMemberDef pattern_members[] = {
{"pattern", T_OBJECT, PAT_OFF(pattern), READONLY},
{"flags", T_INT, PAT_OFF(flags), READONLY},
{"groups", T_PYSSIZET, PAT_OFF(groups), READONLY},
{"groupindex", T_OBJECT, PAT_OFF(groupindex), READONLY},
{NULL} /* Sentinel */
};
static PyTypeObject Pattern_Type = {
PyVarObject_HEAD_INIT(NULL, 0)
"_" SRE_MODULE ".SRE_Pattern",
sizeof(PatternObject), sizeof(SRE_CODE),
(destructor)pattern_dealloc, /* tp_dealloc */
0, /* tp_print */
0, /* tp_getattr */
0, /* tp_setattr */
0, /* tp_reserved */
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_DEFAULT, /* tp_flags */
pattern_doc, /* tp_doc */
0, /* tp_traverse */
0, /* tp_clear */
0, /* tp_richcompare */
offsetof(PatternObject, weakreflist), /* tp_weaklistoffset */
0, /* tp_iter */
0, /* tp_iternext */
pattern_methods, /* tp_methods */
pattern_members, /* tp_members */
};
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->weakreflist = NULL;
self->pattern = NULL;
self->groupindex = NULL;
self->indexgroup = NULL;
self->codesize = n;
for (i = 0; i < n; i++) {
PyObject *o = PyList_GET_ITEM(code, i);
unsigned long value = 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()) {
Py_DECREF(self);
return NULL;
}
if (pattern == Py_None) {
self->isbytes = -1;
}
else {
Py_ssize_t p_length;
int charsize;
Py_buffer view;
view.buf = NULL;
if (!getstring(pattern, &p_length, &self->isbytes,
&charsize, &view)) {
Py_DECREF(self);
return NULL;
}
if (view.buf)
PyBuffer_Release(&view);
}
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.
*/
/* 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) do {} while(0) /* do nothing */
#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 (skip-adj > (Py_uintptr_t)(end - code)) \
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 = 256/SRE_CODE_BITS; /* 256-bit bitmap */
if (offset > (Py_uintptr_t)(end - code))
FAIL;
code += offset;
break;
case SRE_OP_BIGCHARSET:
GET_ARG; /* Number of blocks */
offset = 256/sizeof(SRE_CODE); /* 256-byte table */
if (offset > (Py_uintptr_t)(end - code))
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 * (256/SRE_CODE_BITS); /* 256-bit bitmap times arg */
if (offset > (Py_uintptr_t)(end - code))
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 * (size_t)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, i;
SRE_CODE *newcode;
GET_SKIP;
newcode = code+skip-1;
GET_ARG; flags = arg;
GET_ARG;
GET_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;
GET_ARG; prefix_len = arg;
GET_ARG;
/* Here comes the prefix string */
if (prefix_len > (Py_uintptr_t)(newcode - code))
FAIL;
code += prefix_len;
/* And here comes the overlap table */
if (prefix_len > (Py_uintptr_t)(newcode - code))
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;
if (max > SRE_MAXREPEAT)
FAIL;
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;
if (max > SRE_MAXREPEAT)
FAIL;
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 >= (size_t)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 >= (size_t)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 && skip-3 < (Py_uintptr_t)(end - 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)
{
Py_ssize_t length;
int isbytes, charsize;
Py_buffer view;
PyObject *result;
void* ptr;
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;
}
ptr = getstring(self->string, &length, &isbytes, &charsize, &view);
if (ptr == NULL)
return NULL;
result = getslice(isbytes, ptr,
self->string, self->mark[index], self->mark[index+1]);
if (isbytes && view.buf != NULL)
PyBuffer_Release(&view);
return result;
}
static Py_ssize_t
match_getindex(MatchObject* self, PyObject* index)
{
Py_ssize_t i;
if (index == NULL)
/* Default value */
return 0;
if (PyLong_Check(index))
return PyLong_AsSsize_t(index);
i = -1;
if (self->pattern->groupindex) {
index = PyObject_GetItem(self->pattern->groupindex, index);
if (index) {
if (PyLong_Check(index))
i = PyLong_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_ = NULL;
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 PyLong_FromSsize_t(self->mark[index*2]);
}
static PyObject*
match_end(MatchObject* self, PyObject* args)
{
Py_ssize_t index;
PyObject* index_ = NULL;
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 PyLong_FromSsize_t(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 = PyLong_FromSsize_t(i1);
if (!item)
goto error;
PyTuple_SET_ITEM(pair, 0, item);
item = PyLong_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_ = NULL;
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
}
PyDoc_STRVAR(match_doc,
"The result of re.match() and re.search().\n\
Match objects always have a boolean value of True.");
PyDoc_STRVAR(match_group_doc,
"group([group1, ...]) -> str or tuple.\n\
Return subgroup(s) of the match by indices or names.\n\
For 0 returns the entire match.");
PyDoc_STRVAR(match_start_doc,
"start([group=0]) -> int.\n\
Return index of the start of the substring matched by group.");
PyDoc_STRVAR(match_end_doc,
"end([group=0]) -> int.\n\
Return index of the end of the substring matched by group.");
PyDoc_STRVAR(match_span_doc,
"span([group]) -> tuple.\n\
For MatchObject m, return the 2-tuple (m.start(group), m.end(group)).");
PyDoc_STRVAR(match_groups_doc,
"groups([default=None]) -> tuple.\n\
Return a tuple containing all the subgroups of the match, from 1.\n\
The default argument is used for groups\n\
that did not participate in the match");
PyDoc_STRVAR(match_groupdict_doc,
"groupdict([default=None]) -> dict.\n\
Return a dictionary containing all the named subgroups of the match,\n\
keyed by the subgroup name. The default argument is used for groups\n\
that did not participate in the match");
PyDoc_STRVAR(match_expand_doc,
"expand(template) -> str.\n\
Return the string obtained by doing backslash substitution\n\
on the string template, as done by the sub() method.");
static PyMethodDef match_methods[] = {
{"group", (PyCFunction) match_group, METH_VARARGS, match_group_doc},
{"start", (PyCFunction) match_start, METH_VARARGS, match_start_doc},
{"end", (PyCFunction) match_end, METH_VARARGS, match_end_doc},
{"span", (PyCFunction) match_span, METH_VARARGS, match_span_doc},
{"groups", (PyCFunction) match_groups, METH_VARARGS|METH_KEYWORDS,
match_groups_doc},
{"groupdict", (PyCFunction) match_groupdict, METH_VARARGS|METH_KEYWORDS,
match_groupdict_doc},
{"expand", (PyCFunction) match_expand, METH_O, match_expand_doc},
{"__copy__", (PyCFunction) match_copy, METH_NOARGS},
{"__deepcopy__", (PyCFunction) match_deepcopy, METH_O},
{NULL, NULL}
};
static PyObject *
match_lastindex_get(MatchObject *self)
{
if (self->lastindex >= 0)
return PyLong_FromSsize_t(self->lastindex);
Py_INCREF(Py_None);
return Py_None;
}
static PyObject *
match_lastgroup_get(MatchObject *self)
{
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;
}
static PyObject *
match_regs_get(MatchObject *self)
{
if (self->regs) {
Py_INCREF(self->regs);
return self->regs;
} else
return match_regs(self);
}
static PyObject *
match_repr(MatchObject *self)
{
PyObject *result;
PyObject *group0 = match_getslice_by_index(self, 0, Py_None);
if (group0 == NULL)
return NULL;
result = PyUnicode_FromFormat(
"<%s object; span=(%d, %d), match=%.50R>",
Py_TYPE(self)->tp_name,
self->mark[0], self->mark[1], group0);
Py_DECREF(group0);
return result;
}
static PyGetSetDef match_getset[] = {
{"lastindex", (getter)match_lastindex_get, (setter)NULL},
{"lastgroup", (getter)match_lastgroup_get, (setter)NULL},
{"regs", (getter)match_regs_get, (setter)NULL},
{NULL}
};
#define MATCH_OFF(x) offsetof(MatchObject, x)
static PyMemberDef match_members[] = {
{"string", T_OBJECT, MATCH_OFF(string), READONLY},
{"re", T_OBJECT, MATCH_OFF(pattern), READONLY},
{"pos", T_PYSSIZET, MATCH_OFF(pos), READONLY},
{"endpos", T_PYSSIZET, MATCH_OFF(endpos), READONLY},
{NULL}
};
/* FIXME: implement setattr("string", None) as a special case (to
detach the associated string, if any */
static PyTypeObject Match_Type = {
PyVarObject_HEAD_INIT(NULL,0)
"_" SRE_MODULE ".SRE_Match",
sizeof(MatchObject), sizeof(Py_ssize_t),
(destructor)match_dealloc, /* tp_dealloc */
0, /* tp_print */
0, /* tp_getattr */
0, /* tp_setattr */
0, /* tp_reserved */
(reprfunc)match_repr, /* 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_DEFAULT, /* tp_flags */
match_doc, /* tp_doc */
0, /* tp_traverse */
0, /* tp_clear */
0, /* tp_richcompare */
0, /* tp_weaklistoffset */
0, /* tp_iter */
0, /* tp_iternext */
match_methods, /* tp_methods */
match_members, /* tp_members */
match_getset, /* tp_getset */
};
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_XDECREF(self->pattern);
PyObject_DEL(self);
}
static PyObject*
scanner_match(ScannerObject* self, PyObject *unused)
{
SRE_STATE* state = &self->state;
PyObject* match;
Py_ssize_t status;
state_reset(state);
state->ptr = state->start;
status = sre_match(state, PatternObject_GetCode(self->pattern));
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;
Py_ssize_t status;
state_reset(state);
state->ptr = state->start;
status = sre_search(state, PatternObject_GetCode(self->pattern));
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}
};
#define SCAN_OFF(x) offsetof(ScannerObject, x)
static PyMemberDef scanner_members[] = {
{"pattern", T_OBJECT, SCAN_OFF(pattern), READONLY},
{NULL} /* Sentinel */
};
static PyTypeObject Scanner_Type = {
PyVarObject_HEAD_INIT(NULL, 0)
"_" SRE_MODULE ".SRE_Scanner",
sizeof(ScannerObject), 0,
(destructor)scanner_dealloc,/* tp_dealloc */
0, /* tp_print */
0, /* tp_getattr */
0, /* tp_setattr */
0, /* tp_reserved */
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_DEFAULT, /* tp_flags */
0, /* tp_doc */
0, /* tp_traverse */
0, /* tp_clear */
0, /* tp_richcompare */
0, /* tp_weaklistoffset */
0, /* tp_iter */
0, /* tp_iternext */
scanner_methods, /* tp_methods */
scanner_members, /* tp_members */
0, /* tp_getset */
};
static PyObject*
pattern_scanner(PatternObject* pattern, PyObject* args, PyObject* kw)
{
/* create search state object */
ScannerObject* self;
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:scanner", kwlist,
&string, &start, &end))
return NULL;
/* create scanner object */
self = PyObject_NEW(ScannerObject, &Scanner_Type);
if (!self)
return NULL;
self->pattern = NULL;
string = state_init(&self->state, pattern, string, start, end);
if (!string) {
Py_DECREF(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}
};
static struct PyModuleDef sremodule = {
PyModuleDef_HEAD_INIT,
"_" SRE_MODULE,
NULL,
-1,
_functions,
NULL,
NULL,
NULL,
NULL
};
PyMODINIT_FUNC PyInit__sre(void)
{
PyObject* m;
PyObject* d;
PyObject* x;
/* Patch object types */
if (PyType_Ready(&Pattern_Type) || PyType_Ready(&Match_Type) ||
PyType_Ready(&Scanner_Type))
return NULL;
m = PyModule_Create(&sremodule);
if (m == NULL)
return NULL;
d = PyModule_GetDict(m);
x = PyLong_FromLong(SRE_MAGIC);
if (x) {
PyDict_SetItemString(d, "MAGIC", x);
Py_DECREF(x);
}
x = PyLong_FromLong(sizeof(SRE_CODE));
if (x) {
PyDict_SetItemString(d, "CODESIZE", x);
Py_DECREF(x);
}
x = PyLong_FromUnsignedLong(SRE_MAXREPEAT);
if (x) {
PyDict_SetItemString(d, "MAXREPEAT", x);
Py_DECREF(x);
}
x = PyUnicode_FromString(copyright);
if (x) {
PyDict_SetItemString(d, "copyright", x);
Py_DECREF(x);
}
return m;
}
/* vim:ts=4:sw=4:et
*/
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