[w3m-dev 02811] new regexp implementation

From: aito@fw.ipsj.or.jp

1 files changed, 495 insertions, 130 deletions

diff --git a/regex.c b/regex.c
index 035483a..04bf302 100644
--- a/regex.c
+++ b/regex.c
@@ -1,18 +1,60 @@
-/* $Id: regex.c,v 1.6 2001/11/30 10:10:24 ukai Exp $ */
+/* $Id: regex.c,v 1.7 2002/01/10 04:55:07 ukai Exp $ */
 /* 
  * regex: Regular expression pattern match library
  * 
  * by A.ITO, December 1989
+ * Revised by A.ITO, January 2002
  */
 
 #ifdef REGEX_DEBUG
 #include <sys/types.h>
 #include <malloc.h>
 #endif				/* REGEX_DEBUG */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 #include <ctype.h>
 #include <gc.h>
-#include "fm.h"
 #include "regex.h"
+#include "config.h"
+
+#ifndef NULL
+#define NULL	0
+#endif				/* not NULL */
+
+#if LANG == JA
+#define JP_CHARSET
+#endif
+
+#define RE_ITER_LIMIT   65535
+
+#define RE_MATCHMODE	0x07
+#define	RE_NORMAL	0x00
+#define RE_ANY		0x01
+#define RE_WHICH	0x02
+#define RE_EXCEPT	0x03
+#define RE_SUBREGEX     0x04
+#define RE_BEGIN	0x05
+#define RE_END		0x06
+#define RE_ENDMARK	0x07
+
+#define RE_OPT          0x08
+#define RE_ANYTIME	0x10
+#define RE_IGNCASE      0x40
+
+#define RE_MODE(x)      ((x)->mode&RE_MATCHMODE)
+#define RE_SET_MODE(x,v) ((x)->mode = (((x)->mode&~RE_MATCHMODE)|((v)&RE_MATCHMODE)))
+
+#ifdef REGEX_DEBUG
+void debugre(regexchar *);
+char *lc2c(longchar *, int);
+int verbose;
+#endif				/* REGEX_DEBUG */
+
+#ifndef IS_ALPHA
+#define IS_ALPHA(x) (!((x)&0x80) && isalpha(x))
+#define IS_KANJI1(x) ((x)&0x80)
+#endif
 
 #ifdef JP_CHARSET
 #define RE_KANJI(p)	(((unsigned char)*(p) << 8) | (unsigned char)*((p)+1))
@@ -24,13 +66,10 @@ static Regex DefaultRegex;
 #define CompiledRegex DefaultRegex.re
 #define Cstorage DefaultRegex.storage
 
-static longchar *st_ptr;
-
-static int regmatch(regexchar *, char *, int, int, char **);
+static int regmatch(regexchar *, char *, int, char **);
 static int regmatch1(regexchar *, longchar);
 static int matchWhich(longchar *, longchar);
 
-
 /* 
  * regexCompile: compile regular expression
  */
@@ -42,41 +81,66 @@ regexCompile(char *ex, int igncase)
     return msg;
 }
 
-Regex *
-newRegex(char *ex, int igncase, Regex *regex, char **msg)
+static Regex *
+newRegex0(char **ex, int igncase, Regex *regex, char **msg, int level)
 {
     char *p;
     longchar *r;
-    regexchar *re = regex->re - 1;
+    regexchar *re;
     int m;
+    longchar *st_ptr;
 
-    if (regex == 0)
-	regex = (Regex *)GC_malloc_atomic(sizeof(Regex));
+    if (regex == NULL)
+	regex = (Regex *)GC_malloc(sizeof(Regex));
+    regex->alt_regex = NULL;
+    re = regex->re;
     st_ptr = regex->storage;
-    for (p = ex; *p != '\0'; p++) {
+    for (p = *ex; *p != '\0'; p++) {
+	re->mode = 0;
 	switch (*p) {
 	case '.':
+	    re->p.pattern = NULL;
+	    RE_SET_MODE(re, RE_ANY);
 	    re++;
-	    re->pattern = NULL;
-	    re->mode = RE_ANY;
 	    break;
 	case '$':
+	    re->p.pattern = NULL;
+	    RE_SET_MODE(re, RE_END);
 	    re++;
-	    re->pattern = NULL;
-	    re->mode = RE_END;
 	    break;
 	case '^':
+	    re->p.pattern = NULL;
+	    RE_SET_MODE(re, RE_BEGIN);
 	    re++;
-	    re->pattern = NULL;
-	    re->mode = RE_BEGIN;
 	    break;
-	case '*':
-	    if (!(re->mode & RE_ANY) && re->pattern == NULL) {
+	case '+':
+	    if (re == regex->re ||
+		(RE_MODE(re - 1) != RE_ANY && (re - 1)->p.pattern == NULL)) {
 		if (msg)
 		    *msg = "Invalid regular expression";
 		return NULL;
 	    }
+	    *re = *(re - 1);
 	    re->mode |= RE_ANYTIME;
+	    re++;
+	    break;
+	case '*':
+	    if (re == regex->re ||
+		(RE_MODE(re - 1) != RE_ANY && (re - 1)->p.pattern == NULL)) {
+		if (msg)
+		    *msg = "Invalid regular expression";
+		return NULL;
+	    }
+	    (re - 1)->mode |= RE_ANYTIME;
+	    break;
+	case '?':
+	    if (re == regex->re ||
+		(RE_MODE(re - 1) != RE_ANY && (re - 1)->p.pattern == NULL)) {
+		if (msg)
+		    *msg = "Invalid regular expression";
+		return NULL;
+	    }
+	    (re - 1)->mode |= RE_OPT;
 	    break;
 	case '[':
 	    r = st_ptr;
@@ -110,14 +174,40 @@ newRegex(char *ex, int igncase, Regex *regex, char **msg)
 		    *(st_ptr++) = (unsigned char)*(p++);
 	    }
 	    *(st_ptr++) = '\0';
+	    re->p.pattern = r;
+	    RE_SET_MODE(re, m);
+	    re++;
+	    break;
+	case '|':
+	    RE_SET_MODE(re, RE_ENDMARK);
+	    re++;
+	    p++;
+	    regex->alt_regex = newRegex0(&p, igncase, NULL, msg, level);
+	    if (regex->alt_regex == NULL)
+		return NULL;
+	    *ex = p;
+	    return regex;
+	case '(':
+	    RE_SET_MODE(re, RE_SUBREGEX);
+	    p++;
+	    re->p.sub = newRegex0(&p, igncase, NULL, msg, level + 1);
+	    if (re->p.sub == NULL)
+		return NULL;
 	    re++;
-	    re->pattern = r;
-	    re->mode = m;
 	    break;
+	case ')':
+	    if (level == 0) {
+		if (msg)
+		    *msg = "Too many ')'";
+		return NULL;
+	    }
+	    RE_SET_MODE(re, RE_ENDMARK);
+	    re++;
+	    *ex = p;
+	    return regex;
 	case '\\':
 	    p++;
 	default:
-	    re++;
 #ifdef JP_CHARSET
 	    if (IS_KANJI1(*p)) {
 		*(st_ptr) = RE_KANJI(p);
@@ -126,26 +216,33 @@ newRegex(char *ex, int igncase, Regex *regex, char **msg)
 	    else
 #endif
 		*st_ptr = (unsigned char)*p;
-	    re->pattern = st_ptr;
+	    re->p.pattern = st_ptr;
 	    st_ptr++;
-	    re->mode = RE_NORMAL;
+	    RE_SET_MODE(re, RE_NORMAL);
 	    if (igncase)
 		re->mode |= RE_IGNCASE;
+	    re++;
 	}
-	if (st_ptr >= &Cstorage[STORAGE_MAX] ||
-	    re >= &CompiledRegex[REGEX_MAX]) {
+	if (st_ptr >= &regex->storage[STORAGE_MAX] ||
+	    re >= &regex->re[REGEX_MAX]) {
 	    if (msg)
 		*msg = "Regular expression too long";
 	    return NULL;
 	}
     }
-    re++;
-    re->mode = RE_ENDMARK;
+    RE_SET_MODE(re, RE_ENDMARK);
     if (msg)
 	*msg = NULL;
+    *ex = p;
     return regex;
 }
 
+Regex *
+newRegex(char *ex, int igncase, Regex *regex, char **msg)
+{
+    return newRegex0(&ex, igncase, regex, msg, 0);
+}
+
 /* 
  * regexMatch: match regular expression
  */
@@ -159,20 +256,33 @@ int
 RegexMatch(Regex *re, char *str, int len, int firstp)
 {
     char *p, *ep;
+    char *lpos;
+    Regex *r;
 
     if (str == NULL)
 	return 0;
+    if (len == 0)
+	len = strlen(str);
     re->position = NULL;
-    ep = str + ((len == 0) ? strlen(str) : len);
+    ep = str + len;
     for (p = str; p < ep; p++) {
-	switch (regmatch
-		(re->re, p, ep - p, firstp && (p == str), &re->lposition)) {
-	case 1:
-	    re->position = p;
+	lpos = NULL;
+	re->lposition = NULL;
+	for (r = re; r != NULL; r = r->alt_regex) {
+	    switch (regmatch(r->re, p, firstp && (p == str), &lpos)) {
+	    case 1:		/* matched */
+		re->position = p;
+		if (re->lposition == NULL || re->lposition < lpos)
+		    re->lposition = lpos;
+		break;
+	    case -1:		/* error */
+		re->position = NULL;
+		return -1;
+	    }
+	}
+	if (re->lposition != NULL) {
+	    /* matched */
 	    return 1;
-	case -1:
-	    re->position = NULL;
-	    return -1;
 	}
 #ifdef JP_CHARSET
 	if (IS_KANJI1(*p))
@@ -202,118 +312,306 @@ matchedPosition(char **first, char **last)
 /* 
  * Intermal routines
  */
+
+struct MatchingContext1 {
+    int label;
+    regexchar *re;
+    char *lastpos;
+    char *str;
+    int iter_limit;
+    int n_any;
+    int firstp;
+    char *end_p;
+    Regex *sub_regex;
+    struct MatchingContext1 *sub_ctx;
+    struct MatchingContext2 *ctx2;
+};
+
+struct MatchingContext2 {
+    int label;
+    Regex *regex;
+    char *lastpos;
+    struct MatchingContext1 *ctx;
+    struct MatchingContext2 *ctx2;
+    char *str;
+    int n_any;
+    int firstp;
+};
+
+
+#define YIELD(retval,context,lnum) (context)->label = lnum; return (retval); label##lnum:
+
+static int regmatch_iter(struct MatchingContext1 *, regexchar *, char *, int);
+
 static int
-regmatch(regexchar * re, char *str, int len, int firstp, char **lastpos)
+regmatch_sub_anytime(struct MatchingContext2 *c, Regex *regex,
+		     regexchar * pat2, char *str, int iter_limit, int firstp)
 {
-    char *p = str, *ep = str + len;
-    char *lpos, *llpos = NULL;
-    longchar k;
+    switch (c->label) {
+    case 1:
+	goto label1;
+    case 2:
+	goto label2;
+    case 3:
+	goto label3;
+    }
+    c->ctx = GC_malloc(sizeof(struct MatchingContext1));
+    c->ctx2 = GC_malloc(sizeof(struct MatchingContext2));
+    c->ctx->label = 0;
+    c->regex = regex;
+    c->n_any = 0;
+    c->str = str;
+    c->firstp = firstp;
+    for (;;) {
+	c->ctx->label = 0;
+	while (regmatch_iter(c->ctx, c->regex->re, c->str, c->firstp)) {
+	    c->n_any = c->ctx->lastpos - c->str;
+	    if (c->n_any <= 0)
+		continue;
+	    c->firstp = 0;
+	    if (RE_MODE(pat2) == RE_ENDMARK) {
+		c->lastpos = c->str + c->n_any;
+		YIELD(1, c, 1);
+	    }
+	    else if (regmatch(pat2, c->str + c->n_any,
+			      c->firstp, &c->lastpos) == 1) {
+		YIELD(1, c, 2);
+	    }
+	    if (iter_limit == 1)
+		continue;
+	    c->ctx2->label = 0;
+	    while (regmatch_sub_anytime(c->ctx2, regex, pat2,
+					c->str + c->n_any, iter_limit - 1,
+					c->firstp)) {
 
-    *lastpos = NULL;
-#ifdef REGEX_DEBUG
-    debugre(re, str);
-#endif				/* REGEX_DEBUG */
-    while ((re->mode & RE_ENDMARK) == 0) {
-	if (re->mode & RE_BEGIN) {
-	    if (!firstp)
-		return 0;
-	    re++;
+		c->lastpos = c->ctx2->lastpos;
+		YIELD(1, c, 3);
+	    }
 	}
-	else if (re->mode & RE_ANYTIME) {
-	    short matched, ok = 0;
-	    for (;;) {
-		matched = 0;
-		if (regmatch(re + 1, p, ep - p, firstp, &lpos) == 1) {
-		    llpos = lpos;
-		    matched = 1;
-		    ok = 1;
+	if (c->regex->alt_regex == NULL)
+	    break;
+	c->regex = c->regex->alt_regex;
+    }
+    return 0;
+}
+
+static int
+regmatch_iter(struct MatchingContext1 *c,
+	      regexchar * re, char *str, int firstp)
+{
+    switch (c->label) {
+    case 1:
+	goto label1;
+    case 2:
+	goto label2;
+    case 3:
+	goto label3;
+    case 4:
+	goto label4;
+    case 5:
+	goto label5;
+    case 6:
+	goto label6;
+    case 7:
+	goto label7;
+    }
+    if (RE_MODE(re) == RE_ENDMARK)
+	return 0;
+    c->re = re;
+    c->end_p = str + strlen(str);
+    c->firstp = firstp;
+    c->str = str;
+    c->sub_ctx = NULL;
+    while (RE_MODE(c->re) != RE_ENDMARK) {
+	if (c->re->mode & (RE_ANYTIME | RE_OPT)) {
+	    if (c->re->mode & RE_ANYTIME)
+		c->iter_limit = RE_ITER_LIMIT;
+	    else
+		c->iter_limit = 1;
+	    c->n_any = -1;
+	    while (c->n_any < c->iter_limit) {
+		if (c->str + c->n_any >= c->end_p) {
+		    return 0;
 		}
-		if (p >= ep)
-		    break;
+		if (c->n_any >= 0) {
+		    if (RE_MODE(c->re) == RE_SUBREGEX) {
+			c->ctx2 = GC_malloc(sizeof(struct MatchingContext2));
+			c->ctx2->label = 0;
+			while (regmatch_sub_anytime(c->ctx2,
+						    c->re->p.sub,
+						    c->re + 1,
+						    c->str + c->n_any,
+						    c->iter_limit,
+						    c->firstp)) {
+			    c->n_any = c->ctx2->lastpos - c->str;
+			    c->lastpos = c->ctx2->lastpos;
+			    YIELD(1, c, 1);
+			}
+			return 0;
+		    }
 #ifdef JP_CHARSET
-		if (IS_KANJI1(*p)) {
-		    k = RE_KANJI(p);
-		    if (regmatch1(re, k)) {
-			if (lastpos != NULL)
-			    *lastpos = llpos;
-			p += 2;
+		    else if (IS_KANJI1(c->str[c->n_any])) {
+			longchar k;
+			k = RE_KANJI(c->str + c->n_any);
+			if (regmatch1(c->re, k)) {
+			    c->n_any += 2;
+			}
+			else {
+			    return 0;
+			}
+			c->firstp = 0;
 		    }
-		    else
-			break;
-		}
-		else
 #endif
-		{
-		    k = (unsigned char)*p;
-		    if (regmatch1(re, k)) {
-			p++;
-			if (lastpos != NULL)
-			    *lastpos = llpos;
+		    else {
+			longchar k;
+			k = (unsigned char)c->str[c->n_any];
+			if (regmatch1(c->re, k)) {
+			    c->n_any++;
+			}
+			else {
+			    return 0;
+			}
+			c->firstp = 0;
 		    }
-		    else
-			break;
+		}
+		else
+		    c->n_any++;
+		if (RE_MODE(c->re + 1) == RE_ENDMARK) {
+		    c->lastpos = c->str + c->n_any;
+		    YIELD(1, c, 2);
+		}
+		else if (regmatch(c->re + 1, c->str + c->n_any,
+				  c->firstp, &c->lastpos) == 1) {
+		    YIELD(1, c, 3);
 		}
 	    }
-	    if (lastpos != NULL)
-		*lastpos = llpos;
-	    return ok;
-	}
-	else if (re->mode & RE_END) {
-	    if (lastpos != NULL)
-		*lastpos = p;
-	    return (p >= ep);
+	    return 0;
 	}
-	else {
-	    int a;
+	/* regexp other than pat*, pat+ and pat? */
+	if (c->str >= c->end_p)
+	    return 0;
+	switch (RE_MODE(c->re)) {
+	case RE_BEGIN:
+	    if (!c->firstp)
+		return 0;
+	    c->re++;
+	    break;
+	case RE_END:
+	    c->lastpos = c->str;
+	    c->re++;
+	    YIELD((c->str >= c->end_p), c, 4);
+	    break;
+	case RE_SUBREGEX:
+	    if (c->sub_ctx == NULL) {
+		c->sub_ctx = GC_malloc(sizeof(struct MatchingContext1));
+	    }
+	    c->sub_regex = c->re->p.sub;
+	    for (;;) {
+		c->sub_ctx->label = 0;
+		while (regmatch_iter(c->sub_ctx, c->sub_regex->re,
+				     c->str, c->firstp)) {
+		    if (c->sub_ctx->lastpos != c->str)
+			c->firstp = 0;
+		    if (RE_MODE(c->re + 1) == RE_ENDMARK) {
+			c->lastpos = c->sub_ctx->lastpos;
+			YIELD(1, c, 5);
+		    }
+		    else if (regmatch(c->re + 1, c->sub_ctx->lastpos,
+				      c->firstp, &c->lastpos) == 1) {
+			YIELD(1, c, 6);
+		    }
+		}
+		if (c->sub_regex->alt_regex == NULL)
+		    break;
+		c->sub_regex = c->sub_regex->alt_regex;
+	    }
+	    return 0;
+	default:
 #ifdef JP_CHARSET
-	    if (IS_KANJI1(*p)) {
-		k = RE_KANJI(p);
-		p += 2;
-		a = regmatch1(re, k);
+	    if (IS_KANJI1(*c->str)) {
+		longchar k;
+		k = RE_KANJI(c->str);
+		c->str += 2;
+		if (!regmatch1(c->re, k))
+		    return 0;
 	    }
 	    else
 #endif
 	    {
-		k = (unsigned char)*(p++);
-		a = regmatch1(re, k);
+		longchar k;
+		k = (unsigned char)*(c->str++);
+		if (!regmatch1(c->re, k))
+		    return 0;
 	    }
-	    if (!a)
-		return 0;
-	    else
-		re++;
+	    c->re++;
+	    c->firstp = 0;
+	}
+    }
+    c->lastpos = c->str;
+#ifdef REGEX_DEBUG
+    if (verbose)
+	printf("Succeed: %s %d\n", c->str, c->lastpos - c->str);
+#endif
+    YIELD(1, c, 7);
+    return 0;
+}
+
+static int
+regmatch(regexchar * re, char *str, int firstp, char **lastpos)
+{
+    struct MatchingContext1 contx;
+
+    *lastpos = NULL;
+
+    contx.label = 0;
+    while (regmatch_iter(&contx, re, str, firstp)) {
+#ifdef REGEX_DEBUG
+	char *p;
+	if (verbose) {
+	    printf("regmatch: matched <");
+	    for (p = str; p < contx.lastpos; p++)
+		putchar(*p);
+	    printf(">\n");
 	}
+#endif
+	if (*lastpos == NULL || *lastpos < contx.lastpos)
+	    *lastpos = contx.lastpos;
     }
-    if (lastpos != NULL)
-	*lastpos = p;
+    if (*lastpos == NULL)
+	return 0;
     return 1;
 }
 
+
 static int
 regmatch1(regexchar * re, longchar c)
 {
-    switch (re->mode & RE_MATCHMODE) {
+    switch (RE_MODE(re)) {
     case RE_ANY:
 #ifdef REGEX_DEBUG
-	printf("%c vs any. -> 1\n", c);
+	if (verbose)
+	    printf("%c vs any. -> 1\n", c);
 #endif				/* REGEX_DEBUG */
 	return 1;
     case RE_NORMAL:
 #ifdef REGEX_DEBUG
-	printf("RE=%c vs %c -> %d\n", *re->pattern, c, *re->pattern == c);
+	if (verbose)
+	    printf("RE=%c vs %c -> %d\n", *re->p.pattern, c,
+		   *re->p.pattern == c);
 #endif				/* REGEX_DEBUG */
 	if (re->mode & RE_IGNCASE) {
-	    if (*re->pattern < 127 && c < 127 &&
-		IS_ALPHA(*re->pattern) && IS_ALPHA(c))
-		return tolower(*re->pattern) == tolower(c);
+	    if (*re->p.pattern < 127 && c < 127 &&
+		IS_ALPHA(*re->p.pattern) && IS_ALPHA(c))
+		return tolower(*re->p.pattern) == tolower(c);
 	    else
-		return *re->pattern == c;
+		return *re->p.pattern == c;
 	}
 	else
-	    return (*re->pattern == c);
+	    return (*re->p.pattern == c);
     case RE_WHICH:
-	return matchWhich(re->pattern, c);
+	return matchWhich(re->p.pattern, c);
     case RE_EXCEPT:
-	return !matchWhich(re->pattern, c);
+	return !matchWhich(re->p.pattern, c);
     }
     return 0;
 }
@@ -325,7 +623,8 @@ matchWhich(longchar * pattern, longchar c)
     int ans = 0;
 
 #ifdef REGEX_DEBUG
-    printf("RE pattern = %s char=%c", pattern, c);
+    if (verbose)
+	printf("RE pattern = %s char=%s", lc2c(pattern, 10000), lc2c(&c, 1));
 #endif				/* REGEX_DEBUG */
     while (*p != '\0') {
 	if (*(p + 1) == RE_WHICH_RANGE && *(p + 2) != '\0') {	/* Char class. */
@@ -344,64 +643,130 @@ matchWhich(longchar * pattern, longchar c)
 	}
     }
 #ifdef REGEX_DEBUG
-    printf(" -> %d\n", ans);
+    if (verbose)
+	printf(" -> %d\n", ans);
 #endif				/* REGEX_DEBUG */
     return ans;
 }
 
 #ifdef REGEX_DEBUG
 char *
-lc2c(longchar * x)
+lc2c(longchar * x, int len)
 {
     static char y[100];
     int i = 0;
+    char *r;
 
-    while (x[i]) {
+    while (x[i] && i < len) {
 	if (x[i] == RE_WHICH_RANGE)
-	    y[i] = '-';
+	    y[i++] = '-';
+	else if (x[i] >= 128) {
+	    y[i++] = ((x[i] >> 8) & 0xff);
+	    y[i++] = (x[i] & 0xff);
+	}
 	else
-	    y[i] = x[i];
-	i++;
+	    y[i++] = x[i];
     }
     y[i] = '\0';
-    return y;
+    r = GC_malloc_atomic(i + 1);
+    strcpy(r, y);
+    return r;
 }
 
 void
-debugre(re, s)
-     regexchar *re;
-     char *s;
+debugre(regexchar * re)
 {
-    for (; !(re->mode & RE_ENDMARK); re++) {
-	if (re->mode & RE_BEGIN) {
+    for (; RE_MODE(re) != RE_ENDMARK; re++) {
+	switch (RE_MODE(re)) {
+	case RE_BEGIN:
 	    printf("Begin ");
 	    continue;
-	}
-	else if (re->mode & RE_END) {
+	case RE_END:
 	    printf("End ");
 	    continue;
 	}
 	if (re->mode & RE_ANYTIME)
 	    printf("Anytime-");
+	if (re->mode & RE_OPT)
+	    printf("Opt-");
 
-	switch (re->mode & RE_MATCHMODE) {
+	switch (RE_MODE(re)) {
 	case RE_ANY:
 	    printf("Any ");
 	    break;
 	case RE_NORMAL:
-	    printf("Match-to'%c' ", *re->pattern);
+	    printf("Match-to'%c' ", *re->p.pattern);
 	    break;
 	case RE_WHICH:
-	    printf("One-of\"%s\" ", lc2c(re->pattern));
+	    printf("One-of\"%s\" ", lc2c(re->p.pattern, 10000));
 	    break;
 	case RE_EXCEPT:
-	    printf("Other-than\"%s\" ", lc2c(re->pattern));
+	    printf("Other-than\"%s\" ", lc2c(re->p.pattern, 10000));
 	    break;
+	case RE_SUBREGEX:
+	    {
+		Regex *r = re->p.sub;
+		printf("(");
+		while (r) {
+		    debugre(r->re);
+		    if (r->alt_regex)
+			printf(" | ");
+		    r = r->alt_regex;
+		}
+		printf(")");
+		break;
+	    }
 	default:
 	    printf("Unknown ");
 	}
     }
-    putchar('\n');
 }
 
 #endif				/* REGEX_DEBUG */
+
+#ifdef REGEXTEST
+int
+main(int argc, char **argv)
+{
+    char buf[128], buf2[128];
+    char *msg;
+    Regex *re;
+    char *fpos, *epos;
+    FILE *f = stdin;
+    int i = 1;
+
+#ifdef REGEX_DEBUG
+    for (i = 1; i < argc; i++) {
+	if (strcmp(argv[i], "-v") == 0)
+	    verbose = 1;
+	else
+	    break;
+    }
+#endif
+
+    if (argc > i)
+	f = fopen(argv[i], "r");
+    if (f == NULL) {
+	fprintf(stderr, "Can't open %s\n", argv[i]);
+	exit(1);
+    }
+    while (fscanf(f, "%s%s", buf, buf2) == 2) {
+	re = newRegex(buf, 0, NULL, &msg);
+	if (re == NULL) {
+	    printf("Error on regexp /%s/: %s\n", buf, msg);
+	    exit(1);
+	}
+	if (RegexMatch(re, buf2, 0, 1)) {
+	    printf("/%s/\t%s\t", buf, buf2);
+	    MatchedPosition(re, &fpos, &epos);
+	    while (fpos < epos)
+		putchar(*(fpos++));
+	}
+	else
+	    printf("/%s/\t%s\tno_match", buf, buf2);
+	putchar('\n');
+    }
+    /* notreatched */
+    return 0;
+}
+#endif