Commit db25f328 authored by Guido van Rossum's avatar Guido van Rossum

New versions straight from Jeffrey Ollie's web site

parent db9e20f4
/*
* -*- mode: c-mode; c-file-style: python -*-
*/
/* regexpr.c /* regexpr.c
* *
* Author: Tatu Ylonen <ylo@ngs.fi> * Author: Tatu Ylonen <ylo@ngs.fi>
...@@ -57,6 +61,12 @@ char *realloc(); ...@@ -57,6 +61,12 @@ char *realloc();
#endif /* __STDC__ */ #endif /* __STDC__ */
#endif /* THINK_C */ #endif /* THINK_C */
/* The original code blithely assumed that sizeof(short) == 2. Not
* always true. Original instances of "(short)x" were replaced by
* SHORT(x), where SHORT is #defined below. */
#define SHORT(x) ((x) & 0x8000 ? (x) - 0x10000 : (x))
/* The stack implementation is taken from an idea by Andrew Kuchling. /* The stack implementation is taken from an idea by Andrew Kuchling.
* It's a doubly linked list of arrays. The advantages of this over a * It's a doubly linked list of arrays. The advantages of this over a
* simple linked list are that the number of mallocs required are * simple linked list are that the number of mallocs required are
...@@ -113,35 +123,90 @@ typedef struct item_page_t ...@@ -113,35 +123,90 @@ typedef struct item_page_t
typedef struct match_state typedef struct match_state
{ {
/* The number of registers that have been pushed onto the stack
* since the last failure point. */
int count;
/* Used to control when registers need to be pushed onto the
* stack. */
int level;
/* The number of failure points on the stack. */
int point;
/* Storage for the registers. Each register consists of two
* pointers to characters. So register N is represented as
* start[N] and end[N]. The pointers must be converted to
* offsets from the beginning of the string before returning the
* registers to the calling program. */
char *start[NUM_REGISTERS];
char *end[NUM_REGISTERS];
/* Keeps track of whether a register has changed recently. */
int changed[NUM_REGISTERS];
/* Structure to encapsulate the stack. */ /* Structure to encapsulate the stack. */
struct struct
{ {
/* index into the curent page. If index == 0 and you need /* index into the curent page. If index == 0 and you need
* to pop and item, move to the previous page and set * to pop an item, move to the previous page and set index
* index = STACK_PAGE_SIZE - 1. Otherwise decrement index * = STACK_PAGE_SIZE - 1. Otherwise decrement index to
* to push a page. If index == STACK_PAGE_SIZE and you * push a page. If index == STACK_PAGE_SIZE and you need
* need to push a page move to the next page and set index * to push a page move to the next page and set index =
* = 0. If there is no new next page, allocate a new page * 0. If there is no new next page, allocate a new page
* and link it in. Otherwise, increment index to push a * and link it in. Otherwise, increment index to push a
* page. */ * page. */
int index; int index;
item_page_t *current; /* Pointer to the current page. */ item_page_t *current; /* Pointer to the current page. */
item_page_t first; /* First page is statically allocated. */ item_page_t first; /* First page is statically allocated. */
} stack; } stack;
char *start[NUM_REGISTERS];
char *end[NUM_REGISTERS];
int changed[NUM_REGISTERS];
/* The number of registers that have been pushed onto the stack
* since the last failure point. */
int count;
/* Used to control when registers need to be pushed onto the
* stack. */
int level;
/* The number of failure points on the stack. */
int point;
} match_state; } match_state;
/* Initialize a state object */
/* #define NEW_STATE(state) \ */
/* memset(&state, 0, (void *)(&state.stack) - (void *)(&state)); \ */
/* state.stack.current = &state.stack.first; \ */
/* state.stack.first.prev = NULL; \ */
/* state.stack.first.next = NULL; \ */
/* state.stack.index = 0; \ */
/* state.level = 1 */
#define NEW_STATE(state, nregs) \
{ \
int i; \
for (i = 0; i < nregs; i++) \
{ \
state.start[i] = NULL; \
state.end[i] = NULL; \
state.changed[i] = 0; \
} \
state.stack.current = &state.stack.first; \
state.stack.first.prev = NULL; \
state.stack.first.next = NULL; \
state.stack.index = 0; \
state.level = 1; \
state.count = 0; \
state.level = 0; \
state.point = 0; \
}
/* Free any memory that might have been malloc'd */
#define FREE_STATE(state) \
while(state.stack.first.next != NULL) \
{ \
state.stack.current = state.stack.first.next; \
state.stack.first.next = state.stack.current->next; \
free(state.stack.current); \
}
/* Discard the top 'count' stack items. */ /* Discard the top 'count' stack items. */
#define STACK_DISCARD(stack, count, on_error) \ #define STACK_DISCARD(stack, count, on_error) \
...@@ -226,24 +291,6 @@ else \ ...@@ -226,24 +291,6 @@ else \
#define STACK_EMPTY(stack) ((stack.index == 0) && \ #define STACK_EMPTY(stack) ((stack.index == 0) && \
(stack.current->prev == NULL)) (stack.current->prev == NULL))
/* Initialize a state object */
#define NEW_STATE(state) \
memset(&state, 0, sizeof(match_state)); \
state.stack.current = &state.stack.first; \
state.level = 1
/* Free any memory that might have been malloc'd */
#define FREE_STATE(state) \
while(state.stack.first.next != NULL) \
{ \
state.stack.current = state.stack.first.next; \
state.stack.first.next = state.stack.current->next; \
free(state.stack.current); \
}
/* Return the start of register 'reg' */ /* Return the start of register 'reg' */
#define GET_REG_START(state, reg) (state.start[reg]) #define GET_REG_START(state, reg) (state.start[reg])
...@@ -302,22 +349,6 @@ state.end[reg] = text ...@@ -302,22 +349,6 @@ state.end[reg] = text
/* Update the last failure point with a new position in the text. */ /* Update the last failure point with a new position in the text. */
/* #define UPDATE_FAILURE(state, xtext, on_error) \ */
/* { \ */
/* item_t *item; \ */
/* STACK_DISCARD(state.stack, state.count, on_error); \ */
/* STACK_TOP(state.stack, item, on_error); \ */
/* item->fail.text = xtext; \ */
/* state.count = 0; \ */
/* } */
/* #define UPDATE_FAILURE(state, xtext, on_error) \ */
/* { \ */
/* item_t *item; \ */
/* STACK_BACK(state.stack, item, state.count + 1, on_error); \ */
/* item->fail.text = xtext; \ */
/* } */
#define UPDATE_FAILURE(state, xtext, on_error) \ #define UPDATE_FAILURE(state, xtext, on_error) \
{ \ { \
item_t *item; \ item_t *item; \
...@@ -391,7 +422,8 @@ enum regexp_compiled_ops /* opcodes for compiled regexp */ ...@@ -391,7 +422,8 @@ enum regexp_compiled_ops /* opcodes for compiled regexp */
Cwordbound, /* match if at word boundary */ Cwordbound, /* match if at word boundary */
Cnotwordbound, /* match if not at word boundary */ Cnotwordbound, /* match if not at word boundary */
Csyntaxspec, /* matches syntax code (1 byte follows) */ Csyntaxspec, /* matches syntax code (1 byte follows) */
Cnotsyntaxspec /* matches if syntax code does not match (1 byte foll)*/ Cnotsyntaxspec, /* matches if syntax code does not match (1 byte foll)*/
Crepeat1
}; };
enum regexp_syntax_op /* syntax codes for plain and quoted characters */ enum regexp_syntax_op /* syntax codes for plain and quoted characters */
...@@ -581,6 +613,8 @@ static void re_compile_fastmap_aux(char *code, ...@@ -581,6 +613,8 @@ static void re_compile_fastmap_aux(char *code,
case Cwordbound: case Cwordbound:
case Cnotwordbound: case Cnotwordbound:
{ {
for (a = 0; a < 256; a++)
fastmap[a] = 1;
break; break;
} }
case Csyntaxspec: case Csyntaxspec:
...@@ -648,7 +682,7 @@ static void re_compile_fastmap_aux(char *code, ...@@ -648,7 +682,7 @@ static void re_compile_fastmap_aux(char *code,
{ {
a = (unsigned char)code[pos++]; a = (unsigned char)code[pos++];
a |= (unsigned char)code[pos++] << 8; a |= (unsigned char)code[pos++] << 8;
pos += (int)(short)a; pos += (int)SHORT(a);
if (visited[pos]) if (visited[pos])
{ {
/* argh... the regexp contains empty loops. This is not /* argh... the regexp contains empty loops. This is not
...@@ -664,10 +698,15 @@ static void re_compile_fastmap_aux(char *code, ...@@ -664,10 +698,15 @@ static void re_compile_fastmap_aux(char *code,
{ {
a = (unsigned char)code[pos++]; a = (unsigned char)code[pos++];
a |= (unsigned char)code[pos++] << 8; a |= (unsigned char)code[pos++] << 8;
a = pos + (int)(short)a; a = pos + (int)SHORT(a);
re_compile_fastmap_aux(code, a, visited, can_be_null, fastmap); re_compile_fastmap_aux(code, a, visited, can_be_null, fastmap);
break; break;
} }
case Crepeat1:
{
pos += 2;
break;
}
default: default:
{ {
abort(); /* probably some opcode is missing from this switch */ abort(); /* probably some opcode is missing from this switch */
...@@ -754,10 +793,11 @@ static int re_optimize_star_jump(regexp_t bufp, char *code) ...@@ -754,10 +793,11 @@ static int re_optimize_star_jump(regexp_t bufp, char *code)
char ch; char ch;
int a; int a;
int b; int b;
int num_instructions = 0;
a = (unsigned char)*code++; a = (unsigned char)*code++;
a |= (unsigned char)*code++ << 8; a |= (unsigned char)*code++ << 8;
a = (int)(short)a; a = (int)SHORT(a);
p1 = code + a + 3; /* skip the failure_jump */ p1 = code + a + 3; /* skip the failure_jump */
assert(p1[-3] == Cfailure_jump); assert(p1[-3] == Cfailure_jump);
...@@ -775,6 +815,7 @@ static int re_optimize_star_jump(regexp_t bufp, char *code) ...@@ -775,6 +815,7 @@ static int re_optimize_star_jump(regexp_t bufp, char *code)
/* loop until we find something that consumes a character */ /* loop until we find something that consumes a character */
loop_p1: loop_p1:
num_instructions++;
switch (*p1++) switch (*p1++)
{ {
case Cbol: case Cbol:
...@@ -824,6 +865,7 @@ static int re_optimize_star_jump(regexp_t bufp, char *code) ...@@ -824,6 +865,7 @@ static int re_optimize_star_jump(regexp_t bufp, char *code)
/* now we know that we can't backtrack. */ /* now we know that we can't backtrack. */
while (p1 != p2 - 3) while (p1 != p2 - 3)
{ {
num_instructions++;
switch (*p1++) switch (*p1++)
{ {
case Cend: case Cend:
...@@ -873,11 +915,22 @@ static int re_optimize_star_jump(regexp_t bufp, char *code) ...@@ -873,11 +915,22 @@ static int re_optimize_star_jump(regexp_t bufp, char *code)
} }
} }
make_update_jump:
code -= 3; code -= 3;
a += 3; /* jump to after the Cfailure_jump */ a += 3; /* jump to after the Cfailure_jump */
code[0] = Cupdate_failure_jump; code[0] = Cupdate_failure_jump;
code[1] = a & 0xff; code[1] = a & 0xff;
code[2] = a >> 8; code[2] = a >> 8;
if (num_instructions > 1)
return 1;
assert(num_instructions == 1);
/* if the only instruction matches a single character, we can do
* better
*/
p1 = code + 3 + a; /* start of sole instruction */
if (*p1 == Cset || *p1 == Cexact || *p1 == Canychar ||
*p1 == Csyntaxspec || *p1 == Cnotsyntaxspec)
code[0] = Crepeat1;
return 1; return 1;
make_normal_jump: make_normal_jump:
...@@ -939,6 +992,7 @@ static int re_optimize(regexp_t bufp) ...@@ -939,6 +992,7 @@ static int re_optimize(regexp_t bufp)
case Cjump: case Cjump:
case Cdummy_failure_jump: case Cdummy_failure_jump:
case Cfailure_jump: case Cfailure_jump:
case Crepeat1:
{ {
code += 2; code += 2;
break; break;
...@@ -1111,7 +1165,8 @@ char *re_compile_pattern(char *regex, int size, regexp_t bufp) ...@@ -1111,7 +1165,8 @@ char *re_compile_pattern(char *regex, int size, regexp_t bufp)
re_compile_initialize(); re_compile_initialize();
bufp->used = 0; bufp->used = 0;
bufp->fastmap_accurate = 0; bufp->fastmap_accurate = 0;
bufp->uses_registers = 0; bufp->uses_registers = 1;
bufp->num_registers = 1;
translate = bufp->translate; translate = bufp->translate;
pattern = bufp->buffer; pattern = bufp->buffer;
alloc = bufp->allocated; alloc = bufp->allocated;
...@@ -1289,6 +1344,7 @@ char *re_compile_pattern(char *regex, int size, regexp_t bufp) ...@@ -1289,6 +1344,7 @@ char *re_compile_pattern(char *regex, int size, regexp_t bufp)
STORE(Cstart_memory); STORE(Cstart_memory);
STORE(next_register); STORE(next_register);
open_registers[num_open_registers++] = next_register; open_registers[num_open_registers++] = next_register;
bufp->num_registers++;
next_register++; next_register++;
} }
paren_depth++; paren_depth++;
...@@ -1545,27 +1601,8 @@ int re_match(regexp_t bufp, ...@@ -1545,27 +1601,8 @@ int re_match(regexp_t bufp,
code = bufp->buffer; code = bufp->buffer;
translate = bufp->translate; translate = bufp->translate;
/* translated = NULL; */
/* if (bufp->translate) */
/* { */
/* char *t1; */
/* char *t2; */
/* translated = malloc(size); */ NEW_STATE(state, bufp->num_registers);
/* if (translated == NULL) */
/* goto error; */
/* t1 = string; */
/* t2 = translated; */
/* while(t1 < textend) */
/* *t2++ = bufp->translate[*t1++]; */
/* text = translated + pos; */
/* textstart = translated; */
/* textend = translated + size; */
/* } */
NEW_STATE(state);
continue_matching: continue_matching:
switch (*code++) switch (*code++)
...@@ -1587,7 +1624,7 @@ int re_match(regexp_t bufp, ...@@ -1587,7 +1624,7 @@ int re_match(regexp_t bufp,
} }
else else
{ {
for (a = 1; a < RE_NREGS; a++) for (a = 1; a < bufp->num_registers; a++)
{ {
if ((GET_REG_START(state, a) == NULL) || if ((GET_REG_START(state, a) == NULL) ||
(GET_REG_END(state, a) == NULL)) (GET_REG_END(state, a) == NULL))
...@@ -1599,10 +1636,13 @@ int re_match(regexp_t bufp, ...@@ -1599,10 +1636,13 @@ int re_match(regexp_t bufp,
old_regs->start[a] = GET_REG_START(state, a) - textstart; old_regs->start[a] = GET_REG_START(state, a) - textstart;
old_regs->end[a] = GET_REG_END(state, a) - textstart; old_regs->end[a] = GET_REG_END(state, a) - textstart;
} }
for (; a < RE_NREGS; a++)
{
old_regs->start[a] = -1;
old_regs->end[a] = -1;
}
} }
} }
/* if(translated) */
/* free(translated); */
FREE_STATE(state); FREE_STATE(state);
return match_end - pos; return match_end - pos;
} }
...@@ -1703,18 +1743,18 @@ int re_match(regexp_t bufp, ...@@ -1703,18 +1743,18 @@ int re_match(regexp_t bufp,
{ {
a = (unsigned char)*code++; a = (unsigned char)*code++;
a |= (unsigned char)*code++ << 8; a |= (unsigned char)*code++ << 8;
code += (int)(short)a; code += (int)SHORT(a);
goto continue_matching; goto continue_matching;
} }
case Cdummy_failure_jump: case Cdummy_failure_jump:
{ {
a = (unsigned char)*code++; a = (unsigned char)*code++;
a |= (unsigned char)*code++ << 8; a |= (unsigned char)*code++ << 8;
a = (int)(short)a; a = (int)SHORT(a);
assert(*code == Cfailure_jump); assert(*code == Cfailure_jump);
b = (unsigned char)code[1]; b = (unsigned char)code[1];
b |= (unsigned char)code[2] << 8; b |= (unsigned char)code[2] << 8;
PUSH_FAILURE(state, code + (int)(short)b + 3, NULL, goto error); PUSH_FAILURE(state, code + (int)SHORT(b) + 3, NULL, goto error);
code += a; code += a;
goto continue_matching; goto continue_matching;
} }
...@@ -1722,10 +1762,120 @@ int re_match(regexp_t bufp, ...@@ -1722,10 +1762,120 @@ int re_match(regexp_t bufp,
{ {
a = (unsigned char)*code++; a = (unsigned char)*code++;
a |= (unsigned char)*code++ << 8; a |= (unsigned char)*code++ << 8;
a = (int)(short)a; a = (int)SHORT(a);
PUSH_FAILURE(state, code + a, text, goto error); PUSH_FAILURE(state, code + a, text, goto error);
goto continue_matching; goto continue_matching;
} }
case Crepeat1:
{
char *pinst;
a = (unsigned char)*code++;
a |= (unsigned char)*code++ << 8;
a = (int)SHORT(a);
pinst = code + a;
/* pinst is sole instruction in loop, and it matches a
* single character. Since Crepeat1 was originally a
* Cupdate_failure_jump, we also know that backtracking is
* useless: so long as the single-character expression matches,
* it must be used. Also, in the case of +, we've already
* matched one character, so + can't fail: nothing here can
* cause a failure.
*/
switch (*pinst++)
{
case Cset:
{
if (translate)
{
while (text < textend)
{
ch = translate[(unsigned char)*text];
if (pinst[ch/8] & (1<<(ch & 7)))
text++;
else
break;
}
}
else
{
while (text < textend)
{
ch = (unsigned char)*text;
if (pinst[ch/8] & (1<<(ch & 7)))
text++;
else
break;
}
}
break;
}
case Cexact:
{
ch = (unsigned char)*pinst;
if (translate)
{
while (text < textend &&
translate[(unsigned char)*text] == ch)
text++;
}
else
{
while (text < textend && (unsigned char)*text == ch)
text++;
}
break;
}
case Canychar:
{
while (text < textend && (unsigned char)*text != '\n')
text++;
break;
}
case Csyntaxspec:
{
a = (unsigned char)*pinst;
if (translate)
{
while (text < textend &&
translate[SYNTAX(*text)] == a)
text++;
}
else
{
while (text < textend && SYNTAX(*text) == a)
text++;
}
break;
}
case Cnotsyntaxspec:
{
a = (unsigned char)*pinst;
if (translate)
{
while (text < textend &&
translate[SYNTAX(*text)] != a)
text++;
}
else
{
while (text < textend && SYNTAX(*text) != a)
text++;
}
break;
}
default:
{
abort();
/*NOTREACHED*/
}
}
/* due to the funky way + and * are compiled, the top failure-
* stack entry at this point is actually a success entry --
* update it & pop it
*/
UPDATE_FAILURE(state, text, goto error);
goto fail; /* i.e., succeed <wink/sigh> */
}
case Cbegbuf: case Cbegbuf:
{ {
if (text == textstart) if (text == textstart)
......
/*
* -*- mode: c-mode; c-file-style: python -*-
*/
#ifndef Py_REGEXPR_H #ifndef Py_REGEXPR_H
#define Py_REGEXPR_H #define Py_REGEXPR_H
#ifdef __cplusplus #ifdef __cplusplus
...@@ -5,22 +9,22 @@ extern "C" { ...@@ -5,22 +9,22 @@ extern "C" {
#endif #endif
/* /*
* regexpr.h
regexpr.h *
* Author: Tatu Ylonen <ylo@ngs.fi>
Author: Tatu Ylonen <ylo@ngs.fi> *
* Copyright (c) 1991 Tatu Ylonen, Espoo, Finland
Copyright (c) 1991 Tatu Ylonen, Espoo, Finland *
* Permission to use, copy, modify, distribute, and sell this software
Permission to use, copy, modify, distribute, and sell this software * and its documentation for any purpose is hereby granted without fee,
and its documentation for any purpose is hereby granted without fee, * provided that the above copyright notice appear in all copies. This
provided that the above copyright notice appear in all copies. This * software is provided "as is" without express or implied warranty.
software is provided "as is" without express or implied warranty. *
* Created: Thu Sep 26 17:15:36 1991 ylo
Created: Thu Sep 26 17:15:36 1991 ylo * Last modified: Mon Nov 4 15:49:46 1991 ylo
Last modified: Mon Nov 4 15:49:46 1991 ylo */
*/ /* $Id$ */
#ifndef REGEXPR_H #ifndef REGEXPR_H
#define REGEXPR_H #define REGEXPR_H
...@@ -37,6 +41,7 @@ typedef struct re_pattern_buffer ...@@ -37,6 +41,7 @@ typedef struct re_pattern_buffer
char fastmap_accurate; /* true if fastmap is valid */ char fastmap_accurate; /* true if fastmap is valid */
char can_be_null; /* true if can match empty string */ char can_be_null; /* true if can match empty string */
char uses_registers; /* registers are used and need to be initialized */ char uses_registers; /* registers are used and need to be initialized */
int num_registers; /* number of registers used */
char anchor; /* anchor: 0=none 1=begline 2=begbuf */ char anchor; /* anchor: 0=none 1=begline 2=begbuf */
} *regexp_t; } *regexp_t;
...@@ -77,52 +82,53 @@ typedef struct re_registers ...@@ -77,52 +82,53 @@ typedef struct re_registers
#ifdef HAVE_PROTOTYPES #ifdef HAVE_PROTOTYPES
extern int re_syntax; extern int re_syntax;
/* This is the actual syntax mask. It was added so that Python /* This is the actual syntax mask. It was added so that Python could do
could do syntax-dependent munging of patterns before compilation. */ * syntax-dependent munging of patterns before compilation. */
int re_set_syntax(int syntax); int re_set_syntax(int syntax);
/* This sets the syntax to use and returns the previous syntax. The /* This sets the syntax to use and returns the previous syntax. The
syntax is specified by a bit mask of the above defined bits. */ * syntax is specified by a bit mask of the above defined bits. */
char *re_compile_pattern(char *regex, int regex_size, regexp_t compiled); char *re_compile_pattern(char *regex, int regex_size, regexp_t compiled);
/* This compiles the regexp (given in regex and length in regex_size). /* This compiles the regexp (given in regex and length in regex_size).
This returns NULL if the regexp compiled successfully, and an error * This returns NULL if the regexp compiled successfully, and an error
message if an error was encountered. The buffer field must be * message if an error was encountered. The buffer field must be
initialized to a memory area allocated by malloc (or to NULL) before * initialized to a memory area allocated by malloc (or to NULL) before
use, and the allocated field must be set to its length (or 0 if buffer is * use, and the allocated field must be set to its length (or 0 if
NULL). Also, the translate field must be set to point to a valid * buffer is NULL). Also, the translate field must be set to point to a
translation table, or NULL if it is not used. */ * valid translation table, or NULL if it is not used. */
int re_match(regexp_t compiled, char *string, int size, int pos, int re_match(regexp_t compiled, char *string, int size, int pos,
regexp_registers_t old_regs); regexp_registers_t old_regs);
/* This tries to match the regexp against the string. This returns the /* This tries to match the regexp against the string. This returns the
length of the matched portion, or -1 if the pattern could not be * length of the matched portion, or -1 if the pattern could not be
matched and -2 if an error (such as failure stack overflow) is * matched and -2 if an error (such as failure stack overflow) is
encountered. */ * encountered. */
int re_search(regexp_t compiled, char *string, int size, int startpos, int re_search(regexp_t compiled, char *string, int size, int startpos,
int range, regexp_registers_t regs); int range, regexp_registers_t regs);
/* This rearches for a substring matching the regexp. This returns the first /* This rearches for a substring matching the regexp. This returns the
index at which a match is found. range specifies at how many positions to * first index at which a match is found. range specifies at how many
try matching; positive values indicate searching forwards, and negative * positions to try matching; positive values indicate searching
values indicate searching backwards. mstop specifies the offset beyond * forwards, and negative values indicate searching backwards. mstop
which a match must not go. This returns -1 if no match is found, and * specifies the offset beyond which a match must not go. This returns
-2 if an error (such as failure stack overflow) is encountered. */ * -1 if no match is found, and -2 if an error (such as failure stack
* overflow) is encountered. */
void re_compile_fastmap(regexp_t compiled); void re_compile_fastmap(regexp_t compiled);
/* This computes the fastmap for the regexp. For this to have any effect, /* This computes the fastmap for the regexp. For this to have any effect,
the calling program must have initialized the fastmap field to point * the calling program must have initialized the fastmap field to point
to an array of 256 characters. */ * to an array of 256 characters. */
char *re_comp(char *s); char *re_comp(char *s);
/* BSD 4.2 regex library routine re_comp. This compiles the regexp into /* BSD 4.2 regex library routine re_comp. This compiles the regexp into
an internal buffer. This returns NULL if the regexp was compiled * an internal buffer. This returns NULL if the regexp was compiled
successfully, and an error message if there was an error. */ * successfully, and an error message if there was an error. */
int re_exec(char *s); int re_exec(char *s);
/* BSD 4.2 regexp library routine re_exec. This returns true if the string /* BSD 4.2 regexp library routine re_exec. This returns true if the
matches the regular expression (that is, a matching part is found * string matches the regular expression (that is, a matching part is
anywhere in the string). */ * found anywhere in the string). */
#else /* HAVE_PROTOTYPES */ #else /* HAVE_PROTOTYPES */
......
/***********************************************************
Copyright 1991-1995 by Stichting Mathematisch Centrum, Amsterdam,
The Netherlands.
All Rights Reserved
Permission to use, copy, modify, and distribute this software and its
documentation for any purpose and without fee is hereby granted,
provided that the above copyright notice appear in all copies and that
both that copyright notice and this permission notice appear in
supporting documentation, and that the names of Stichting Mathematisch
Centrum or CWI or Corporation for National Research Initiatives or
CNRI not be used in advertising or publicity pertaining to
distribution of the software without specific, written prior
permission.
While CWI is the initial source for this software, a modified version
is made available by the Corporation for National Research Initiatives
(CNRI) at the Internet address ftp://ftp.python.org.
STICHTING MATHEMATISCH CENTRUM AND CNRI DISCLAIM ALL WARRANTIES WITH
REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH
CENTRUM OR CNRI BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL
DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
PERFORMANCE OF THIS SOFTWARE.
******************************************************************/
/* $Id$ */
/* Regular expression objects */
/* This uses Tatu Ylonen's copyleft-free reimplementation of
GNU regular expressions */
#include "Python.h"
#include <ctype.h>
#include "regexpr.h"
static PyObject *ReopError; /* Exception */
static PyObject *
makeresult(regs, num_regs)
struct re_registers *regs;
int num_regs;
{
PyObject *v;
int i;
static PyObject *filler = NULL;
if (filler == NULL) {
filler = Py_BuildValue("(ii)", -1, -1);
if (filler == NULL)
return NULL;
}
v = PyTuple_New(num_regs);
if (v == NULL)
return NULL;
for (i = 0; i < num_regs; i++) {
int lo = regs->start[i];
int hi = regs->end[i];
PyObject *w;
if (lo == -1 && hi == -1) {
w = filler;
Py_INCREF(w);
}
else
w = Py_BuildValue("(ii)", lo, hi);
if (w == NULL || PyTuple_SetItem(v, i, w) < 0) {
Py_DECREF(v);
return NULL;
}
}
return v;
}
static PyObject *
reop_match(self, args)
PyObject *self;
PyObject *args;
{
char *string;
int fastmaplen, stringlen;
int can_be_null, anchor, i;
int num_regs, flags, pos, result;
struct re_pattern_buffer bufp;
struct re_registers re_regs;
if (!PyArg_Parse(args, "(s#iiis#is#i)",
&(bufp.buffer), &(bufp.allocated),
&num_regs, &flags, &can_be_null,
&(bufp.fastmap), &fastmaplen,
&anchor,
&string, &stringlen,
&pos))
return NULL;
/* XXX sanity-check the input data */
bufp.used=bufp.allocated;
bufp.translate=NULL;
bufp.fastmap_accurate=1;
bufp.can_be_null=can_be_null;
bufp.uses_registers=1;
bufp.num_registers=num_regs;
bufp.anchor=anchor;
for(i=0; i<num_regs; i++) {re_regs.start[i]=-1; re_regs.end[i]=-1;}
result = re_match(&bufp,
string, stringlen, pos,
&re_regs);
if (result < -1) {
/* Failure like stack overflow */
PyErr_SetString(ReopError, "match failure");
return NULL;
}
return makeresult(&re_regs, num_regs);
}
static PyObject *
reop_search(self, args)
PyObject *self;
PyObject *args;
{
char *string;
int fastmaplen, stringlen;
int can_be_null, anchor, i;
int num_regs, flags, pos, result;
struct re_pattern_buffer bufp;
struct re_registers re_regs;
if (!PyArg_Parse(args, "(s#iiis#is#i)",
&(bufp.buffer), &(bufp.allocated),
&num_regs, &flags, &can_be_null,
&(bufp.fastmap), &fastmaplen,
&anchor,
&string, &stringlen,
&pos))
return NULL;
/* XXX sanity-check the input data */
bufp.used=bufp.allocated;
bufp.translate=NULL;
bufp.fastmap_accurate=1;
bufp.can_be_null=can_be_null;
bufp.uses_registers=1;
bufp.num_registers=1;
bufp.anchor=anchor;
for(i=0; i<num_regs; i++) {re_regs.start[i]=-1; re_regs.end[i]=-1;}
result = re_search(&bufp,
string, stringlen, pos, stringlen-pos,
&re_regs);
if (result < -1) {
/* Failure like stack overflow */
PyErr_SetString(ReopError, "match failure");
return NULL;
}
return makeresult(&re_regs, num_regs);
}
#if 0
/* Functions originally in the regsub module.
Added June 1, 1997.
*/
/* A cache of previously used patterns is maintained. Notice that if
you change the reop syntax flag, entries in the cache are
invalidated.
XXX Solution: use (syntax flag, pattern) as keys? Clear the cache
every so often, or once it gets past a certain size?
*/
static PyObject *cache_dict=NULL;
/* Accept an object; if it's a reop pattern, Py_INCREF it and return
it. If it's a string, a reop object is compiled and cached.
*/
static reopobject *
cached_compile(pattern)
PyObject *pattern;
{
reopobject *p2;
if (!PyString_Check(pattern))
{
/* It's not a string, so assume it's a compiled reop object */
/* XXX check that! */
Py_INCREF(pattern);
return (reopobject*)pattern;
}
if (cache_dict==NULL)
{
cache_dict=PyDict_New();
if (cache_dict==NULL)
{
return (reopobject*)NULL;
}
}
/* See if the pattern has already been cached; if so, return that
reop object */
p2=(reopobject*)PyDict_GetItem(cache_dict, pattern);
if (p2)
{
Py_INCREF(p2);
return (reopobject*)p2;
}
/* Compile the pattern and cache it */
p2=(reopobject*)newreopobject(pattern, NULL, pattern, NULL);
if (!p2) return p2;
PyDict_SetItem(cache_dict, pattern, (PyObject*)p2);
return p2;
}
static PyObject *
internal_split(args, retain)
PyObject *args;
int retain;
{
PyObject *newlist, *s;
reopobject *pattern;
int maxsplit=0, count=0, length, next=0, result;
int match_end=0; /* match_start is defined below */
char *start;
if (!PyArg_ParseTuple(args, "s#Oi", &start, &length, &pattern,
&maxsplit))
{
PyErr_Clear();
if (!PyArg_ParseTuple(args, "s#O", &start, &length, &pattern))
return NULL;
}
pattern=cached_compile((PyObject *)pattern);
if (!pattern) return NULL;
newlist=PyList_New(0);
if (!newlist) return NULL;
do
{
result = re_search(&pattern->re_patbuf,
start, length, next, length-next,
&pattern->re_regs);
if (result < -1)
{ /* Erk... an error happened during the reop search */
Py_DECREF(newlist);
PyErr_SetString(ReopError, "match failure");
return NULL;
}
if (next<=result)
{
int match_start=pattern->re_regs.start[0];
int oldmatch_end=match_end;
match_end=pattern->re_regs.end[0];
if (match_start==match_end)
{ /* A zero-length match; increment to the next position */
next=result+1;
match_end=oldmatch_end;
continue;
}
/* Append the string up to the start of the match */
s=PyString_FromStringAndSize(start+oldmatch_end, match_start-oldmatch_end);
if (!s)
{
Py_DECREF(newlist);
return NULL;
}
PyList_Append(newlist, s);
Py_DECREF(s);
if (retain)
{
/* Append a string containing whatever matched */
s=PyString_FromStringAndSize(start+match_start, match_end-match_start);
if (!s)
{
Py_DECREF(newlist);
return NULL;
}
PyList_Append(newlist, s);
Py_DECREF(s);
}
/* Update the pointer, and increment the count of splits */
next=match_end; count++;
}
} while (result!=-1 && !(maxsplit && maxsplit==count) &&
next<length);
s=PyString_FromStringAndSize(start+match_end, length-match_end);
if (!s)
{
Py_DECREF(newlist);
return NULL;
}
PyList_Append(newlist, s);
Py_DECREF(s);
Py_DECREF(pattern);
return newlist;
}
static PyObject *
reop_split(self, args)
PyObject *self;
PyObject *args;
{
return internal_split(args, 0);
}
static PyObject *
reop_splitx(self, args)
PyObject *self;
PyObject *args;
{
return internal_split(args, 1);
}
#endif
static struct PyMethodDef reop_global_methods[] = {
{"match", reop_match, 0},
{"search", reop_search, 0},
#if 0
{"split", reop_split, 0},
{"splitx", reop_splitx, 0},
#endif
{NULL, NULL} /* sentinel */
};
void
initreop()
{
PyObject *m, *d, *v;
int i;
char *s;
m = Py_InitModule("reop", reop_global_methods);
d = PyModule_GetDict(m);
/* Initialize reop.error exception */
v = ReopError = PyString_FromString("reop.error");
if (v == NULL || PyDict_SetItemString(d, "error", v) != 0)
goto finally;
/* Initialize reop.casefold constant */
if (!(v = PyString_FromStringAndSize((char *)NULL, 256)))
goto finally;
if (!(s = PyString_AsString(v)))
goto finally;
for (i = 0; i < 256; i++) {
if (isupper(i))
s[i] = tolower(i);
else
s[i] = i;
}
if (PyDict_SetItemString(d, "casefold", v) < 0)
goto finally;
Py_DECREF(v);
if (!PyErr_Occurred())
return;
finally:
Py_FatalError("can't initialize reop module");
}
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