/*
 * Secret Labs' Regular Expression Engine
 *
 * regular expression matching engine
 *
 * Copyright (c) 1997-2001 by Secret Labs AB. All rights reserved.
 *
 * See the _sre.c file for information on usage and redistribution.
 */

#ifndef SRE_INCLUDED
#define SRE_INCLUDED

#include "sre_constants.h"

/* size of a code word (must be unsigned short or larger, and
 large enough to hold a UCS4 character) */
#define SRE_CODE Py_UCS4
#if SIZEOF_SIZE_T > 4
# define SRE_MAXREPEAT (~(SRE_CODE)0)
# define SRE_MAXGROUPS ((~(SRE_CODE)0) / 2)
#else
# define SRE_MAXREPEAT ((SRE_CODE)PY_SSIZE_T_MAX)
# define SRE_MAXGROUPS ((SRE_CODE)PY_SSIZE_T_MAX / SIZEOF_SIZE_T / 2)
#endif

typedef struct {
 PyObject_VAR_HEAD
 Py_ssize_t groups; /* must be first! */
 PyObject* groupindex; /* dict */
 PyObject* indexgroup; /* tuple */
 /* compatibility */
 PyObject* pattern; /* pattern source (or None) */
 int flags; /* flags used when compiling pattern source */
 PyObject *weakreflist; /* List of weak references */
 int isbytes; /* pattern type (1 - bytes, 0 - string, -1 - None) */
 /* pattern code */
 Py_ssize_t codesize;
 SRE_CODE code[1];
} PatternObject;

#define PatternObject_GetCode(o) (((PatternObject*)(o))->code)

typedef struct {
 PyObject_VAR_HEAD
 PyObject* string; /* link to the target string (must be first) */
 PyObject* regs; /* cached list of matching spans */
 PatternObject* pattern; /* link to the regex (pattern) object */
 Py_ssize_t pos, endpos; /* current target slice */
 Py_ssize_t lastindex; /* last index marker seen by the engine (-1 if none) */
 Py_ssize_t groups; /* number of groups (start/end marks) */
 Py_ssize_t mark[1];
} MatchObject;

typedef struct SRE_REPEAT_T {
 Py_ssize_t count;
 SRE_CODE* pattern; /* points to REPEAT operator arguments */
 void* last_ptr; /* helper to check for infinite loops */
 struct SRE_REPEAT_T *prev; /* points to previous repeat context */
} SRE_REPEAT;

typedef struct {
 /* string pointers */
 void* ptr; /* current position (also end of current slice) */
 void* beginning; /* start of original string */
 void* start; /* start of current slice */
 void* end; /* end of original string */
 /* attributes for the match object */
 PyObject* string;
 Py_buffer buffer;
 Py_ssize_t pos, endpos;
 int isbytes;
 int charsize; /* character size */
 /* registers */
 Py_ssize_t lastindex;
 Py_ssize_t lastmark;
 void** mark;
 int match_all;
 int must_advance;
 /* dynamically allocated stuff */
 char* data_stack;
 size_t data_stack_size;
 size_t data_stack_base;
 /* current repeat context */
 SRE_REPEAT *repeat;
} SRE_STATE;

typedef struct {
 PyObject_HEAD
 PyObject* pattern;
 SRE_STATE state;
} ScannerObject;

#endif