856 lines
20 KiB
C
856 lines
20 KiB
C
|
/****************************************************************
|
||
|
Copyright (C) Lucent Technologies 1997
|
||
|
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 the copyright notice and this
|
||
|
permission notice and warranty disclaimer appear in supporting
|
||
|
documentation, and that the name Lucent Technologies or any of
|
||
|
its entities not be used in advertising or publicity pertaining
|
||
|
to distribution of the software without specific, written prior
|
||
|
permission.
|
||
|
|
||
|
LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
|
||
|
INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
|
||
|
IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES 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.
|
||
|
****************************************************************/
|
||
|
|
||
|
/* lasciate ogne speranza, voi ch'entrate. */
|
||
|
|
||
|
#define DEBUG
|
||
|
|
||
|
#include <ctype.h>
|
||
|
#include <stdio.h>
|
||
|
#include <string.h>
|
||
|
#include <stdlib.h>
|
||
|
#include "awk.h"
|
||
|
#include "ytab.h"
|
||
|
|
||
|
#define HAT (NCHARS-2) /* matches ^ in regular expr */
|
||
|
/* NCHARS is 2**n */
|
||
|
#define MAXLIN 22
|
||
|
|
||
|
#define type(v) (v)->nobj /* badly overloaded here */
|
||
|
#define info(v) (v)->ntype /* badly overloaded here */
|
||
|
#define left(v) (v)->narg[0]
|
||
|
#define right(v) (v)->narg[1]
|
||
|
#define parent(v) (v)->nnext
|
||
|
|
||
|
#define LEAF case CCL: case NCCL: case CHAR: case DOT: case FINAL: case ALL:
|
||
|
#define UNARY case STAR: case PLUS: case QUEST:
|
||
|
|
||
|
/* encoding in tree Nodes:
|
||
|
leaf (CCL, NCCL, CHAR, DOT, FINAL, ALL):
|
||
|
left is index, right contains value or pointer to value
|
||
|
unary (STAR, PLUS, QUEST): left is child, right is null
|
||
|
binary (CAT, OR): left and right are children
|
||
|
parent contains pointer to parent
|
||
|
*/
|
||
|
|
||
|
|
||
|
int *setvec;
|
||
|
int *tmpset;
|
||
|
int maxsetvec = 0;
|
||
|
|
||
|
int rtok; /* next token in current re */
|
||
|
int rlxval;
|
||
|
static uschar *rlxstr;
|
||
|
static uschar *prestr; /* current position in current re */
|
||
|
static uschar *lastre; /* origin of last re */
|
||
|
|
||
|
static int setcnt;
|
||
|
static int poscnt;
|
||
|
|
||
|
char *patbeg;
|
||
|
int patlen;
|
||
|
|
||
|
#define NFA 20 /* cache this many dynamic fa's */
|
||
|
fa *fatab[NFA];
|
||
|
int nfatab = 0; /* entries in fatab */
|
||
|
|
||
|
fa *makedfa(char *s, int anchor) /* returns dfa for reg expr s */
|
||
|
{
|
||
|
int i, use, nuse;
|
||
|
fa *pfa;
|
||
|
static int now = 1;
|
||
|
|
||
|
if (setvec == 0) { /* first time through any RE */
|
||
|
maxsetvec = MAXLIN;
|
||
|
setvec = (int *) malloc(maxsetvec * sizeof(int));
|
||
|
tmpset = (int *) malloc(maxsetvec * sizeof(int));
|
||
|
if (setvec == 0 || tmpset == 0)
|
||
|
overflo("out of space initializing makedfa");
|
||
|
}
|
||
|
|
||
|
if (compile_time) /* a constant for sure */
|
||
|
return mkdfa(s, anchor);
|
||
|
for (i = 0; i < nfatab; i++) /* is it there already? */
|
||
|
if (fatab[i]->anchor == anchor
|
||
|
&& strcmp(fatab[i]->restr, s) == 0) {
|
||
|
fatab[i]->use = now++;
|
||
|
return fatab[i];
|
||
|
}
|
||
|
pfa = mkdfa(s, anchor);
|
||
|
if (nfatab < NFA) { /* room for another */
|
||
|
fatab[nfatab] = pfa;
|
||
|
fatab[nfatab]->use = now++;
|
||
|
nfatab++;
|
||
|
return pfa;
|
||
|
}
|
||
|
use = fatab[0]->use; /* replace least-recently used */
|
||
|
nuse = 0;
|
||
|
for (i = 1; i < nfatab; i++)
|
||
|
if (fatab[i]->use < use) {
|
||
|
use = fatab[i]->use;
|
||
|
nuse = i;
|
||
|
}
|
||
|
freefa(fatab[nuse]);
|
||
|
fatab[nuse] = pfa;
|
||
|
pfa->use = now++;
|
||
|
return pfa;
|
||
|
}
|
||
|
|
||
|
fa *mkdfa(char *s, int anchor) /* does the real work of making a dfa */
|
||
|
/* anchor = 1 for anchored matches, else 0 */
|
||
|
{
|
||
|
Node *p, *p1;
|
||
|
fa *f;
|
||
|
|
||
|
p = reparse(s);
|
||
|
p1 = op2(CAT, op2(STAR, op2(ALL, NIL, NIL), NIL), p);
|
||
|
/* put ALL STAR in front of reg. exp. */
|
||
|
p1 = op2(CAT, p1, op2(FINAL, NIL, NIL));
|
||
|
/* put FINAL after reg. exp. */
|
||
|
|
||
|
poscnt = 0;
|
||
|
penter(p1); /* enter parent pointers and leaf indices */
|
||
|
if ((f = (fa *) calloc(1, sizeof(fa) + poscnt*sizeof(rrow))) == NULL)
|
||
|
overflo("out of space for fa");
|
||
|
f->accept = poscnt-1; /* penter has computed number of positions in re */
|
||
|
cfoll(f, p1); /* set up follow sets */
|
||
|
freetr(p1);
|
||
|
if ((f->posns[0] = (int *) calloc(1, *(f->re[0].lfollow)*sizeof(int))) == NULL)
|
||
|
overflo("out of space in makedfa");
|
||
|
if ((f->posns[1] = (int *) calloc(1, sizeof(int))) == NULL)
|
||
|
overflo("out of space in makedfa");
|
||
|
*f->posns[1] = 0;
|
||
|
f->initstat = makeinit(f, anchor);
|
||
|
f->anchor = anchor;
|
||
|
f->restr = (uschar *) tostring(s);
|
||
|
return f;
|
||
|
}
|
||
|
|
||
|
int makeinit(fa *f, int anchor)
|
||
|
{
|
||
|
int i, k;
|
||
|
|
||
|
f->curstat = 2;
|
||
|
f->out[2] = 0;
|
||
|
f->reset = 0;
|
||
|
k = *(f->re[0].lfollow);
|
||
|
xfree(f->posns[2]);
|
||
|
if ((f->posns[2] = (int *) calloc(1, (k+1)*sizeof(int))) == NULL)
|
||
|
overflo("out of space in makeinit");
|
||
|
for (i=0; i <= k; i++) {
|
||
|
(f->posns[2])[i] = (f->re[0].lfollow)[i];
|
||
|
}
|
||
|
if ((f->posns[2])[1] == f->accept)
|
||
|
f->out[2] = 1;
|
||
|
for (i=0; i < NCHARS; i++)
|
||
|
f->gototab[2][i] = 0;
|
||
|
f->curstat = cgoto(f, 2, HAT);
|
||
|
if (anchor) {
|
||
|
*f->posns[2] = k-1; /* leave out position 0 */
|
||
|
for (i=0; i < k; i++) {
|
||
|
(f->posns[0])[i] = (f->posns[2])[i];
|
||
|
}
|
||
|
|
||
|
f->out[0] = f->out[2];
|
||
|
if (f->curstat != 2)
|
||
|
--(*f->posns[f->curstat]);
|
||
|
}
|
||
|
return f->curstat;
|
||
|
}
|
||
|
|
||
|
void penter(Node *p) /* set up parent pointers and leaf indices */
|
||
|
{
|
||
|
switch (type(p)) {
|
||
|
LEAF
|
||
|
info(p) = poscnt;
|
||
|
poscnt++;
|
||
|
break;
|
||
|
UNARY
|
||
|
penter(left(p));
|
||
|
parent(left(p)) = p;
|
||
|
break;
|
||
|
case CAT:
|
||
|
case OR:
|
||
|
penter(left(p));
|
||
|
penter(right(p));
|
||
|
parent(left(p)) = p;
|
||
|
parent(right(p)) = p;
|
||
|
break;
|
||
|
default: /* can't happen */
|
||
|
FATAL("can't happen: unknown type %d in penter", type(p));
|
||
|
break;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
void freetr(Node *p) /* free parse tree */
|
||
|
{
|
||
|
switch (type(p)) {
|
||
|
LEAF
|
||
|
xfree(p);
|
||
|
break;
|
||
|
UNARY
|
||
|
freetr(left(p));
|
||
|
xfree(p);
|
||
|
break;
|
||
|
case CAT:
|
||
|
case OR:
|
||
|
freetr(left(p));
|
||
|
freetr(right(p));
|
||
|
xfree(p);
|
||
|
break;
|
||
|
default: /* can't happen */
|
||
|
FATAL("can't happen: unknown type %d in freetr", type(p));
|
||
|
break;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/* in the parsing of regular expressions, metacharacters like . have */
|
||
|
/* to be seen literally; \056 is not a metacharacter. */
|
||
|
|
||
|
int hexstr(char **pp) /* find and eval hex string at pp, return new p */
|
||
|
{ /* only pick up one 8-bit byte (2 chars) */
|
||
|
uschar *p;
|
||
|
int n = 0;
|
||
|
int i;
|
||
|
|
||
|
for (i = 0, p = (uschar *) *pp; i < 2 && isxdigit(*p); i++, p++) {
|
||
|
if (isdigit(*p))
|
||
|
n = 16 * n + *p - '0';
|
||
|
else if (*p >= 'a' && *p <= 'f')
|
||
|
n = 16 * n + *p - 'a' + 10;
|
||
|
else if (*p >= 'A' && *p <= 'F')
|
||
|
n = 16 * n + *p - 'A' + 10;
|
||
|
}
|
||
|
*pp = (char *) p;
|
||
|
return n;
|
||
|
}
|
||
|
|
||
|
#define isoctdigit(c) ((c) >= '0' && (c) <= '7') /* multiple use of arg */
|
||
|
|
||
|
int quoted(char **pp) /* pick up next thing after a \\ */
|
||
|
/* and increment *pp */
|
||
|
{
|
||
|
char *p = *pp;
|
||
|
int c;
|
||
|
|
||
|
if ((c = *p++) == 't')
|
||
|
c = '\t';
|
||
|
else if (c == 'n')
|
||
|
c = '\n';
|
||
|
else if (c == 'f')
|
||
|
c = '\f';
|
||
|
else if (c == 'r')
|
||
|
c = '\r';
|
||
|
else if (c == 'b')
|
||
|
c = '\b';
|
||
|
else if (c == '\\')
|
||
|
c = '\\';
|
||
|
else if (c == 'x') { /* hexadecimal goo follows */
|
||
|
c = hexstr(&p); /* this adds a null if number is invalid */
|
||
|
} else if (isoctdigit(c)) { /* \d \dd \ddd */
|
||
|
int n = c - '0';
|
||
|
if (isoctdigit(*p)) {
|
||
|
n = 8 * n + *p++ - '0';
|
||
|
if (isoctdigit(*p))
|
||
|
n = 8 * n + *p++ - '0';
|
||
|
}
|
||
|
c = n;
|
||
|
} /* else */
|
||
|
/* c = c; */
|
||
|
*pp = p;
|
||
|
return c;
|
||
|
}
|
||
|
|
||
|
char *cclenter(char *argp) /* add a character class */
|
||
|
{
|
||
|
int i, c, c2;
|
||
|
uschar *p = (uschar *) argp;
|
||
|
uschar *op, *bp;
|
||
|
static uschar *buf = 0;
|
||
|
static int bufsz = 100;
|
||
|
|
||
|
op = p;
|
||
|
if (buf == 0 && (buf = (uschar *) malloc(bufsz)) == NULL)
|
||
|
FATAL("out of space for character class [%.10s...] 1", p);
|
||
|
bp = buf;
|
||
|
for (i = 0; (c = *p++) != 0; ) {
|
||
|
if (c == '\\') {
|
||
|
c = quoted((char **) &p);
|
||
|
} else if (c == '-' && i > 0 && bp[-1] != 0) {
|
||
|
if (*p != 0) {
|
||
|
c = bp[-1];
|
||
|
c2 = *p++;
|
||
|
if (c2 == '\\')
|
||
|
c2 = quoted((char **) &p);
|
||
|
if (c > c2) { /* empty; ignore */
|
||
|
bp--;
|
||
|
i--;
|
||
|
continue;
|
||
|
}
|
||
|
while (c < c2) {
|
||
|
if (!adjbuf((char **) &buf, &bufsz, bp-buf+2, 100, (char **) &bp, 0))
|
||
|
FATAL("out of space for character class [%.10s...] 2", p);
|
||
|
*bp++ = ++c;
|
||
|
i++;
|
||
|
}
|
||
|
continue;
|
||
|
}
|
||
|
}
|
||
|
if (!adjbuf((char **) &buf, &bufsz, bp-buf+2, 100, (char **) &bp, 0))
|
||
|
FATAL("out of space for character class [%.10s...] 3", p);
|
||
|
*bp++ = c;
|
||
|
i++;
|
||
|
}
|
||
|
*bp = 0;
|
||
|
dprintf( ("cclenter: in = |%s|, out = |%s|\n", op, buf) );
|
||
|
xfree(op);
|
||
|
return (char *) tostring((char *) buf);
|
||
|
}
|
||
|
|
||
|
void overflo(char *s)
|
||
|
{
|
||
|
FATAL("regular expression too big: %.30s...", s);
|
||
|
}
|
||
|
|
||
|
void cfoll(fa *f, Node *v) /* enter follow set of each leaf of vertex v into lfollow[leaf] */
|
||
|
{
|
||
|
int i;
|
||
|
int *p;
|
||
|
|
||
|
switch (type(v)) {
|
||
|
LEAF
|
||
|
f->re[info(v)].ltype = type(v);
|
||
|
f->re[info(v)].lval.np = right(v);
|
||
|
while (f->accept >= maxsetvec) { /* guessing here! */
|
||
|
maxsetvec *= 4;
|
||
|
setvec = (int *) realloc(setvec, maxsetvec * sizeof(int));
|
||
|
tmpset = (int *) realloc(tmpset, maxsetvec * sizeof(int));
|
||
|
if (setvec == 0 || tmpset == 0)
|
||
|
overflo("out of space in cfoll()");
|
||
|
}
|
||
|
for (i = 0; i <= f->accept; i++)
|
||
|
setvec[i] = 0;
|
||
|
setcnt = 0;
|
||
|
follow(v); /* computes setvec and setcnt */
|
||
|
if ((p = (int *) calloc(1, (setcnt+1)*sizeof(int))) == NULL)
|
||
|
overflo("out of space building follow set");
|
||
|
f->re[info(v)].lfollow = p;
|
||
|
*p = setcnt;
|
||
|
for (i = f->accept; i >= 0; i--)
|
||
|
if (setvec[i] == 1)
|
||
|
*++p = i;
|
||
|
break;
|
||
|
UNARY
|
||
|
cfoll(f,left(v));
|
||
|
break;
|
||
|
case CAT:
|
||
|
case OR:
|
||
|
cfoll(f,left(v));
|
||
|
cfoll(f,right(v));
|
||
|
break;
|
||
|
default: /* can't happen */
|
||
|
FATAL("can't happen: unknown type %d in cfoll", type(v));
|
||
|
}
|
||
|
}
|
||
|
|
||
|
int first(Node *p) /* collects initially active leaves of p into setvec */
|
||
|
/* returns 1 if p matches empty string */
|
||
|
{
|
||
|
int b, lp;
|
||
|
|
||
|
switch (type(p)) {
|
||
|
LEAF
|
||
|
lp = info(p); /* look for high-water mark of subscripts */
|
||
|
while (setcnt >= maxsetvec || lp >= maxsetvec) { /* guessing here! */
|
||
|
maxsetvec *= 4;
|
||
|
setvec = (int *) realloc(setvec, maxsetvec * sizeof(int));
|
||
|
tmpset = (int *) realloc(tmpset, maxsetvec * sizeof(int));
|
||
|
if (setvec == 0 || tmpset == 0)
|
||
|
overflo("out of space in first()");
|
||
|
}
|
||
|
if (setvec[lp] != 1) {
|
||
|
setvec[lp] = 1;
|
||
|
setcnt++;
|
||
|
}
|
||
|
if (type(p) == CCL && (*(char *) right(p)) == '\0')
|
||
|
return(0); /* empty CCL */
|
||
|
else return(1);
|
||
|
case PLUS:
|
||
|
if (first(left(p)) == 0) return(0);
|
||
|
return(1);
|
||
|
case STAR:
|
||
|
case QUEST:
|
||
|
first(left(p));
|
||
|
return(0);
|
||
|
case CAT:
|
||
|
if (first(left(p)) == 0 && first(right(p)) == 0) return(0);
|
||
|
return(1);
|
||
|
case OR:
|
||
|
b = first(right(p));
|
||
|
if (first(left(p)) == 0 || b == 0) return(0);
|
||
|
return(1);
|
||
|
}
|
||
|
FATAL("can't happen: unknown type %d in first", type(p)); /* can't happen */
|
||
|
return(-1);
|
||
|
}
|
||
|
|
||
|
void follow(Node *v) /* collects leaves that can follow v into setvec */
|
||
|
{
|
||
|
Node *p;
|
||
|
|
||
|
if (type(v) == FINAL)
|
||
|
return;
|
||
|
p = parent(v);
|
||
|
switch (type(p)) {
|
||
|
case STAR:
|
||
|
case PLUS:
|
||
|
first(v);
|
||
|
follow(p);
|
||
|
return;
|
||
|
|
||
|
case OR:
|
||
|
case QUEST:
|
||
|
follow(p);
|
||
|
return;
|
||
|
|
||
|
case CAT:
|
||
|
if (v == left(p)) { /* v is left child of p */
|
||
|
if (first(right(p)) == 0) {
|
||
|
follow(p);
|
||
|
return;
|
||
|
}
|
||
|
} else /* v is right child */
|
||
|
follow(p);
|
||
|
return;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
int member(int c, char *sarg) /* is c in s? */
|
||
|
{
|
||
|
uschar *s = (uschar *) sarg;
|
||
|
|
||
|
while (*s)
|
||
|
if (c == *s++)
|
||
|
return(1);
|
||
|
return(0);
|
||
|
}
|
||
|
|
||
|
int match(fa *f, char *p0) /* shortest match ? */
|
||
|
{
|
||
|
int s, ns;
|
||
|
uschar *p = (uschar *) p0;
|
||
|
|
||
|
s = f->reset ? makeinit(f,0) : f->initstat;
|
||
|
if (f->out[s])
|
||
|
return(1);
|
||
|
do {
|
||
|
if ((ns = f->gototab[s][*p]) != 0)
|
||
|
s = ns;
|
||
|
else
|
||
|
s = cgoto(f, s, *p);
|
||
|
if (f->out[s])
|
||
|
return(1);
|
||
|
} while (*p++ != 0);
|
||
|
return(0);
|
||
|
}
|
||
|
|
||
|
int pmatch(fa *f, char *p0) /* longest match, for sub */
|
||
|
{
|
||
|
int s, ns;
|
||
|
uschar *p = (uschar *) p0;
|
||
|
uschar *q;
|
||
|
int i, k;
|
||
|
|
||
|
s = f->reset ? makeinit(f,1) : f->initstat;
|
||
|
patbeg = (char *) p;
|
||
|
patlen = -1;
|
||
|
do {
|
||
|
q = p;
|
||
|
do {
|
||
|
if (f->out[s]) /* final state */
|
||
|
patlen = q-p;
|
||
|
if ((ns = f->gototab[s][*q]) != 0)
|
||
|
s = ns;
|
||
|
else
|
||
|
s = cgoto(f, s, *q);
|
||
|
if (s == 1) { /* no transition */
|
||
|
if (patlen >= 0) {
|
||
|
patbeg = (char *) p;
|
||
|
return(1);
|
||
|
}
|
||
|
else
|
||
|
goto nextin; /* no match */
|
||
|
}
|
||
|
} while (*q++ != 0);
|
||
|
if (f->out[s])
|
||
|
patlen = q-p-1; /* don't count $ */
|
||
|
if (patlen >= 0) {
|
||
|
patbeg = (char *) p;
|
||
|
return(1);
|
||
|
}
|
||
|
nextin:
|
||
|
s = 2;
|
||
|
if (f->reset) {
|
||
|
for (i = 2; i <= f->curstat; i++)
|
||
|
xfree(f->posns[i]);
|
||
|
k = *f->posns[0];
|
||
|
if ((f->posns[2] = (int *) calloc(1, (k+1)*sizeof(int))) == NULL)
|
||
|
overflo("out of space in pmatch");
|
||
|
for (i = 0; i <= k; i++)
|
||
|
(f->posns[2])[i] = (f->posns[0])[i];
|
||
|
f->initstat = f->curstat = 2;
|
||
|
f->out[2] = f->out[0];
|
||
|
for (i = 0; i < NCHARS; i++)
|
||
|
f->gototab[2][i] = 0;
|
||
|
}
|
||
|
} while (*p++ != 0);
|
||
|
return (0);
|
||
|
}
|
||
|
|
||
|
int nematch(fa *f, char *p0) /* non-empty match, for sub */
|
||
|
{
|
||
|
int s, ns;
|
||
|
uschar *p = (uschar *) p0;
|
||
|
uschar *q;
|
||
|
int i, k;
|
||
|
|
||
|
s = f->reset ? makeinit(f,1) : f->initstat;
|
||
|
patlen = -1;
|
||
|
while (*p) {
|
||
|
q = p;
|
||
|
do {
|
||
|
if (f->out[s]) /* final state */
|
||
|
patlen = q-p;
|
||
|
if ((ns = f->gototab[s][*q]) != 0)
|
||
|
s = ns;
|
||
|
else
|
||
|
s = cgoto(f, s, *q);
|
||
|
if (s == 1) { /* no transition */
|
||
|
if (patlen > 0) {
|
||
|
patbeg = (char *) p;
|
||
|
return(1);
|
||
|
} else
|
||
|
goto nnextin; /* no nonempty match */
|
||
|
}
|
||
|
} while (*q++ != 0);
|
||
|
if (f->out[s])
|
||
|
patlen = q-p-1; /* don't count $ */
|
||
|
if (patlen > 0 ) {
|
||
|
patbeg = (char *) p;
|
||
|
return(1);
|
||
|
}
|
||
|
nnextin:
|
||
|
s = 2;
|
||
|
if (f->reset) {
|
||
|
for (i = 2; i <= f->curstat; i++)
|
||
|
xfree(f->posns[i]);
|
||
|
k = *f->posns[0];
|
||
|
if ((f->posns[2] = (int *) calloc(1, (k+1)*sizeof(int))) == NULL)
|
||
|
overflo("out of state space");
|
||
|
for (i = 0; i <= k; i++)
|
||
|
(f->posns[2])[i] = (f->posns[0])[i];
|
||
|
f->initstat = f->curstat = 2;
|
||
|
f->out[2] = f->out[0];
|
||
|
for (i = 0; i < NCHARS; i++)
|
||
|
f->gototab[2][i] = 0;
|
||
|
}
|
||
|
p++;
|
||
|
}
|
||
|
return (0);
|
||
|
}
|
||
|
|
||
|
Node *reparse(char *p) /* parses regular expression pointed to by p */
|
||
|
{ /* uses relex() to scan regular expression */
|
||
|
Node *np;
|
||
|
|
||
|
dprintf( ("reparse <%s>\n", p) );
|
||
|
lastre = prestr = (uschar *) p; /* prestr points to string to be parsed */
|
||
|
rtok = relex();
|
||
|
if (rtok == '\0')
|
||
|
FATAL("empty regular expression");
|
||
|
np = regexp();
|
||
|
if (rtok != '\0')
|
||
|
FATAL("syntax error in regular expression %s at %s", lastre, prestr);
|
||
|
return(np);
|
||
|
}
|
||
|
|
||
|
Node *regexp(void) /* top-level parse of reg expr */
|
||
|
{
|
||
|
return (alt(concat(primary())));
|
||
|
}
|
||
|
|
||
|
Node *primary(void)
|
||
|
{
|
||
|
Node *np;
|
||
|
|
||
|
switch (rtok) {
|
||
|
case CHAR:
|
||
|
np = op2(CHAR, NIL, itonp(rlxval));
|
||
|
rtok = relex();
|
||
|
return (unary(np));
|
||
|
case ALL:
|
||
|
rtok = relex();
|
||
|
return (unary(op2(ALL, NIL, NIL)));
|
||
|
case DOT:
|
||
|
rtok = relex();
|
||
|
return (unary(op2(DOT, NIL, NIL)));
|
||
|
case CCL:
|
||
|
np = op2(CCL, NIL, (Node*) cclenter((char *) rlxstr));
|
||
|
rtok = relex();
|
||
|
return (unary(np));
|
||
|
case NCCL:
|
||
|
np = op2(NCCL, NIL, (Node *) cclenter((char *) rlxstr));
|
||
|
rtok = relex();
|
||
|
return (unary(np));
|
||
|
case '^':
|
||
|
rtok = relex();
|
||
|
return (unary(op2(CHAR, NIL, itonp(HAT))));
|
||
|
case '$':
|
||
|
rtok = relex();
|
||
|
return (unary(op2(CHAR, NIL, NIL)));
|
||
|
case '(':
|
||
|
rtok = relex();
|
||
|
if (rtok == ')') { /* special pleading for () */
|
||
|
rtok = relex();
|
||
|
return unary(op2(CCL, NIL, (Node *) tostring("")));
|
||
|
}
|
||
|
np = regexp();
|
||
|
if (rtok == ')') {
|
||
|
rtok = relex();
|
||
|
return (unary(np));
|
||
|
}
|
||
|
else
|
||
|
FATAL("syntax error in regular expression %s at %s", lastre, prestr);
|
||
|
default:
|
||
|
FATAL("illegal primary in regular expression %s at %s", lastre, prestr);
|
||
|
}
|
||
|
return 0; /*NOTREACHED*/
|
||
|
}
|
||
|
|
||
|
Node *concat(Node *np)
|
||
|
{
|
||
|
switch (rtok) {
|
||
|
case CHAR: case DOT: case ALL: case CCL: case NCCL: case '$': case '(':
|
||
|
return (concat(op2(CAT, np, primary())));
|
||
|
}
|
||
|
return (np);
|
||
|
}
|
||
|
|
||
|
Node *alt(Node *np)
|
||
|
{
|
||
|
if (rtok == OR) {
|
||
|
rtok = relex();
|
||
|
return (alt(op2(OR, np, concat(primary()))));
|
||
|
}
|
||
|
return (np);
|
||
|
}
|
||
|
|
||
|
Node *unary(Node *np)
|
||
|
{
|
||
|
switch (rtok) {
|
||
|
case STAR:
|
||
|
rtok = relex();
|
||
|
return (unary(op2(STAR, np, NIL)));
|
||
|
case PLUS:
|
||
|
rtok = relex();
|
||
|
return (unary(op2(PLUS, np, NIL)));
|
||
|
case QUEST:
|
||
|
rtok = relex();
|
||
|
return (unary(op2(QUEST, np, NIL)));
|
||
|
default:
|
||
|
return (np);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
int relex(void) /* lexical analyzer for reparse */
|
||
|
{
|
||
|
int c, n;
|
||
|
int cflag;
|
||
|
static uschar *buf = 0;
|
||
|
static int bufsz = 100;
|
||
|
uschar *bp;
|
||
|
|
||
|
switch (c = *prestr++) {
|
||
|
case '|': return OR;
|
||
|
case '*': return STAR;
|
||
|
case '+': return PLUS;
|
||
|
case '?': return QUEST;
|
||
|
case '.': return DOT;
|
||
|
case '\0': prestr--; return '\0';
|
||
|
case '^':
|
||
|
case '$':
|
||
|
case '(':
|
||
|
case ')':
|
||
|
return c;
|
||
|
case '\\':
|
||
|
rlxval = quoted((char **) &prestr);
|
||
|
return CHAR;
|
||
|
default:
|
||
|
rlxval = c;
|
||
|
return CHAR;
|
||
|
case '[':
|
||
|
if (buf == 0 && (buf = (uschar *) malloc(bufsz)) == NULL)
|
||
|
FATAL("out of space in reg expr %.10s..", lastre);
|
||
|
bp = buf;
|
||
|
if (*prestr == '^') {
|
||
|
cflag = 1;
|
||
|
prestr++;
|
||
|
}
|
||
|
else
|
||
|
cflag = 0;
|
||
|
n = 2 * strlen(prestr)+1;
|
||
|
if (!adjbuf((char **) &buf, &bufsz, n, n, (char **) &bp, 0))
|
||
|
FATAL("out of space for reg expr %.10s...", lastre);
|
||
|
for (; ; ) {
|
||
|
if ((c = *prestr++) == '\\') {
|
||
|
*bp++ = '\\';
|
||
|
if ((c = *prestr++) == '\0')
|
||
|
FATAL("nonterminated character class %.20s...", lastre);
|
||
|
*bp++ = c;
|
||
|
/* } else if (c == '\n') { */
|
||
|
/* FATAL("newline in character class %.20s...", lastre); */
|
||
|
} else if (c == '\0') {
|
||
|
FATAL("nonterminated character class %.20s", lastre);
|
||
|
} else if (bp == buf) { /* 1st char is special */
|
||
|
*bp++ = c;
|
||
|
} else if (c == ']') {
|
||
|
*bp++ = 0;
|
||
|
rlxstr = (uschar *) tostring((char *) buf);
|
||
|
if (cflag == 0)
|
||
|
return CCL;
|
||
|
else
|
||
|
return NCCL;
|
||
|
} else
|
||
|
*bp++ = c;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
int cgoto(fa *f, int s, int c)
|
||
|
{
|
||
|
int i, j, k;
|
||
|
int *p, *q;
|
||
|
|
||
|
if (c < 0 || c > 255)
|
||
|
FATAL("can't happen: neg char %d in cgoto", c);
|
||
|
while (f->accept >= maxsetvec) { /* guessing here! */
|
||
|
maxsetvec *= 4;
|
||
|
setvec = (int *) realloc(setvec, maxsetvec * sizeof(int));
|
||
|
tmpset = (int *) realloc(tmpset, maxsetvec * sizeof(int));
|
||
|
if (setvec == 0 || tmpset == 0)
|
||
|
overflo("out of space in cgoto()");
|
||
|
}
|
||
|
for (i = 0; i <= f->accept; i++)
|
||
|
setvec[i] = 0;
|
||
|
setcnt = 0;
|
||
|
/* compute positions of gototab[s,c] into setvec */
|
||
|
p = f->posns[s];
|
||
|
for (i = 1; i <= *p; i++) {
|
||
|
if ((k = f->re[p[i]].ltype) != FINAL) {
|
||
|
if ((k == CHAR && c == ptoi(f->re[p[i]].lval.np))
|
||
|
|| (k == DOT && c != 0 && c != HAT)
|
||
|
|| (k == ALL && c != 0)
|
||
|
|| (k == CCL && member(c, (char *) f->re[p[i]].lval.up))
|
||
|
|| (k == NCCL && !member(c, (char *) f->re[p[i]].lval.up) && c != 0 && c != HAT)) {
|
||
|
q = f->re[p[i]].lfollow;
|
||
|
for (j = 1; j <= *q; j++) {
|
||
|
if (q[j] >= maxsetvec) {
|
||
|
maxsetvec *= 4;
|
||
|
setvec = (int *) realloc(setvec, maxsetvec * sizeof(int));
|
||
|
tmpset = (int *) realloc(setvec, maxsetvec * sizeof(int));
|
||
|
if (setvec == 0 || tmpset == 0)
|
||
|
overflo("cgoto overflow");
|
||
|
}
|
||
|
if (setvec[q[j]] == 0) {
|
||
|
setcnt++;
|
||
|
setvec[q[j]] = 1;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
/* determine if setvec is a previous state */
|
||
|
tmpset[0] = setcnt;
|
||
|
j = 1;
|
||
|
for (i = f->accept; i >= 0; i--)
|
||
|
if (setvec[i]) {
|
||
|
tmpset[j++] = i;
|
||
|
}
|
||
|
/* tmpset == previous state? */
|
||
|
for (i = 1; i <= f->curstat; i++) {
|
||
|
p = f->posns[i];
|
||
|
if ((k = tmpset[0]) != p[0])
|
||
|
goto different;
|
||
|
for (j = 1; j <= k; j++)
|
||
|
if (tmpset[j] != p[j])
|
||
|
goto different;
|
||
|
/* setvec is state i */
|
||
|
f->gototab[s][c] = i;
|
||
|
return i;
|
||
|
different:;
|
||
|
}
|
||
|
|
||
|
/* add tmpset to current set of states */
|
||
|
if (f->curstat >= NSTATES-1) {
|
||
|
f->curstat = 2;
|
||
|
f->reset = 1;
|
||
|
for (i = 2; i < NSTATES; i++)
|
||
|
xfree(f->posns[i]);
|
||
|
} else
|
||
|
++(f->curstat);
|
||
|
for (i = 0; i < NCHARS; i++)
|
||
|
f->gototab[f->curstat][i] = 0;
|
||
|
xfree(f->posns[f->curstat]);
|
||
|
if ((p = (int *) calloc(1, (setcnt+1)*sizeof(int))) == NULL)
|
||
|
overflo("out of space in cgoto");
|
||
|
|
||
|
f->posns[f->curstat] = p;
|
||
|
f->gototab[s][c] = f->curstat;
|
||
|
for (i = 0; i <= setcnt; i++)
|
||
|
p[i] = tmpset[i];
|
||
|
if (setvec[f->accept])
|
||
|
f->out[f->curstat] = 1;
|
||
|
else
|
||
|
f->out[f->curstat] = 0;
|
||
|
return f->curstat;
|
||
|
}
|
||
|
|
||
|
|
||
|
void freefa(fa *f) /* free a finite automaton */
|
||
|
{
|
||
|
int i;
|
||
|
|
||
|
if (f == NULL)
|
||
|
return;
|
||
|
for (i = 0; i <= f->curstat; i++)
|
||
|
xfree(f->posns[i]);
|
||
|
for (i = 0; i <= f->accept; i++) {
|
||
|
xfree(f->re[i].lfollow);
|
||
|
if (f->re[i].ltype == CCL || f->re[i].ltype == NCCL)
|
||
|
xfree((f->re[i].lval.np));
|
||
|
}
|
||
|
xfree(f->restr);
|
||
|
xfree(f);
|
||
|
}
|