merge upstream/master

1 files changed, 0 insertions, 1328 deletions

diff --git a/jam-files/engine/regexp.c b/jam-files/engine/regexp.c
deleted file mode 100644
index 30197a2f..00000000
--- a/jam-files/engine/regexp.c
+++ /dev/null
@@ -1,1328 +0,0 @@
-/*
- * regcomp and regexec -- regsub and regerror are elsewhere
- *
- *  Copyright (c) 1986 by University of Toronto.
- *  Written by Henry Spencer.  Not derived from licensed software.
- *
- *  Permission is granted to anyone to use this software for any
- *  purpose on any computer system, and to redistribute it freely,
- *  subject to the following restrictions:
- *
- *  1. The author is not responsible for the consequences of use of
- *      this software, no matter how awful, even if they arise
- *      from defects in it.
- *
- *  2. The origin of this software must not be misrepresented, either
- *      by explicit claim or by omission.
- *
- *  3. Altered versions must be plainly marked as such, and must not
- *      be misrepresented as being the original software.
- *** THIS IS AN ALTERED VERSION.  It was altered by John Gilmore,
- *** hoptoad!gnu, on 27 Dec 1986, to add \n as an alternative to |
- *** to assist in implementing egrep.
- *** THIS IS AN ALTERED VERSION.  It was altered by John Gilmore,
- *** hoptoad!gnu, on 27 Dec 1986, to add \< and \> for word-matching
- *** as in BSD grep and ex.
- *** THIS IS AN ALTERED VERSION.  It was altered by John Gilmore,
- *** hoptoad!gnu, on 28 Dec 1986, to optimize characters quoted with \.
- *** THIS IS AN ALTERED VERSION.  It was altered by James A. Woods,
- *** ames!jaw, on 19 June 1987, to quash a regcomp() redundancy.
- *** THIS IS AN ALTERED VERSION.  It was altered by Christopher Seiwald
- *** seiwald@vix.com, on 28 August 1993, for use in jam.  Regmagic.h
- *** was moved into regexp.h, and the include of regexp.h now uses "'s
- *** to avoid conflicting with the system regexp.h.  Const, bless its
- *** soul, was removed so it can compile everywhere.  The declaration
- *** of strchr() was in conflict on AIX, so it was removed (as it is
- *** happily defined in string.h).
- *** THIS IS AN ALTERED VERSION.  It was altered by Christopher Seiwald
- *** seiwald@perforce.com, on 20 January 2000, to use function prototypes.
- *
- * Beware that some of this code is subtly aware of the way operator precedence
- * is structured in regular expressions. Serious changes in regular-expression
- * syntax might require a total rethink.
- */
-
-
-#include "jam.h"
-#include "regexp.h"
-#include <stdio.h>
-#include <ctype.h>
-#ifndef ultrix
-    #include <stdlib.h>
-#endif
-#include <string.h>
-
-
-/*
- * The "internal use only" fields in regexp.h are present to pass info from
- * compile to execute that permits the execute phase to run lots faster on
- * simple cases. They are:
- :
- *  regstart char that must begin a match; '\0' if none obvious.
- *  reganch  is the match anchored (at beginning-of-line only)?
- *  regmust  string (pointer into program) that match must include, or NULL.
- *  regmlen  length of regmust string.
- *
- * Regstart and reganch permit very fast decisions on suitable starting points
- * for a match, cutting down the work a lot.  Regmust permits fast rejection of
- * lines that cannot possibly match.  The regmust tests are costly enough that
- * regcomp() supplies a regmust only if the r.e. contains something potentially
- * expensive (at present, the only such thing detected is * or + at the start of
- * the r.e., which can involve a lot of backup). Regmlen is supplied because the
- * test in regexec() needs it and regcomp() is computing it anyway.
- */
-
-/*
- * Structure for regexp "program". This is essentially a linear encoding of a
- * nondeterministic finite-state machine (aka syntax charts or "railroad normal
- * form" in parsing technology). Each node is an opcode plus a "next" pointer,
- * possibly plus an operand. "Next" pointers of all nodes except BRANCH
- * implement concatenation; a "next" pointer with a BRANCH on both ends of it is
- * connecting two alternatives. [Here we have one of the subtle syntax
- * dependencies: an individual BRANCH, as opposed to a collection of them, is
- * never concatenated with anything because of operator precedence.] The operand
- * of some types of node is a literal string; for others, it is a node leading
- * into a sub-FSM. In particular, the operand of a BRANCH node is the first node
- * of the branch. [NB this is *not* a tree structure: the tail of the branch
- * connects to the thing following the set of BRANCHes.] The opcodes are:
- */
-
-/* definition   number  opnd?   meaning */
-#define END 0   /* no   End of program. */
-#define BOL 1   /* no   Match "" at beginning of line. */
-#define EOL 2   /* no   Match "" at end of line. */
-#define ANY 3   /* no   Match any one character. */
-#define ANYOF   4   /* str  Match any character in this string. */
-#define ANYBUT  5   /* str  Match any character not in this string. */
-#define BRANCH  6   /* node Match this alternative, or the next... */
-#define BACK    7   /* no   Match "", "next" ptr points backward. */
-#define EXACTLY 8   /* str  Match this string. */
-#define NOTHING 9   /* no   Match empty string. */
-#define STAR    10  /* node Match this (simple) thing 0 or more times. */
-#define PLUS    11  /* node Match this (simple) thing 1 or more times. */
-#define WORDA   12  /* no   Match "" at wordchar, where prev is nonword */
-#define WORDZ   13  /* no   Match "" at nonwordchar, where prev is word */
-#define OPEN    20  /* no   Mark this point in input as start of #n. */
-            /*  OPEN+1 is number 1, etc. */
-#define CLOSE   30  /* no   Analogous to OPEN. */
-
-
-/*
- * Opcode notes:
- *
- * BRANCH   The set of branches constituting a single choice are hooked
- *      together with their "next" pointers, since precedence prevents
- *      anything being concatenated to any individual branch.  The
- *      "next" pointer of the last BRANCH in a choice points to the
- *      thing following the whole choice.  This is also where the
- *      final "next" pointer of each individual branch points; each
- *      branch starts with the operand node of a BRANCH node.
- *
- * BACK     Normal "next" pointers all implicitly point forward; BACK
- *      exists to make loop structures possible.
- *
- * STAR,PLUS    '?', and complex '*' and '+', are implemented as circular
- *      BRANCH structures using BACK.  Simple cases (one character
- *      per match) are implemented with STAR and PLUS for speed
- *      and to minimize recursive plunges.
- *
- * OPEN,CLOSE   ...are numbered at compile time.
- */
-
-/*
- * A node is one char of opcode followed by two chars of "next" pointer.
- * "Next" pointers are stored as two 8-bit pieces, high order first.  The
- * value is a positive offset from the opcode of the node containing it.
- * An operand, if any, simply follows the node.  (Note that much of the
- * code generation knows about this implicit relationship.)
- *
- * Using two bytes for the "next" pointer is vast overkill for most things,
- * but allows patterns to get big without disasters.
- */
-#define OP(p)   (*(p))
-#define NEXT(p) (((*((p)+1)&0377)<<8) + (*((p)+2)&0377))
-#define OPERAND(p)  ((p) + 3)
-
-/*
- * See regmagic.h for one further detail of program structure.
- */
-
-
-/*
- * Utility definitions.
- */
-#ifndef CHARBITS
-#define UCHARAT(p)  ((int)*(unsigned char *)(p))
-#else
-#define UCHARAT(p)  ((int)*(p)&CHARBITS)
-#endif
-
-#define FAIL(m) { regerror(m); return(NULL); }
-#define ISMULT(c)   ((c) == '*' || (c) == '+' || (c) == '?')
-
-/*
- * Flags to be passed up and down.
- */
-#define HASWIDTH    01  /* Known never to match null string. */
-#define SIMPLE      02  /* Simple enough to be STAR/PLUS operand. */
-#define SPSTART     04  /* Starts with * or +. */
-#define WORST       0   /* Worst case. */
-
-/*
- * Global work variables for regcomp().
- */
-static char *regparse;      /* Input-scan pointer. */
-static int regnpar;     /* () count. */
-static char regdummy;
-static char *regcode;       /* Code-emit pointer; &regdummy = don't. */
-static long regsize;        /* Code size. */
-
-/*
- * Forward declarations for regcomp()'s friends.
- */
-#ifndef STATIC
-#define STATIC  static
-#endif
-STATIC char *reg( int paren, int *flagp );
-STATIC char *regbranch( int *flagp );
-STATIC char *regpiece( int *flagp );
-STATIC char *regatom( int *flagp );
-STATIC char *regnode( int op );
-STATIC char *regnext( register char *p );
-STATIC void regc( int b );
-STATIC void reginsert( char op, char *opnd );
-STATIC void regtail( char *p, char *val );
-STATIC void regoptail( char *p, char *val );
-#ifdef STRCSPN
-STATIC int strcspn();
-#endif
-
-/*
- - regcomp - compile a regular expression into internal code
- *
- * We can't allocate space until we know how big the compiled form will be,
- * but we can't compile it (and thus know how big it is) until we've got a
- * place to put the code.  So we cheat:  we compile it twice, once with code
- * generation turned off and size counting turned on, and once "for real".
- * This also means that we don't allocate space until we are sure that the
- * thing really will compile successfully, and we never have to move the
- * code and thus invalidate pointers into it.  (Note that it has to be in
- * one piece because free() must be able to free it all.)
- *
- * Beware that the optimization-preparation code in here knows about some
- * of the structure of the compiled regexp.
- */
-regexp *
-regcomp( char *exp )
-{
-    register regexp *r;
-    register char *scan;
-    register char *longest;
-    register unsigned len;
-    int flags;
-
-    if (exp == NULL)
-        FAIL("NULL argument");
-
-    /* First pass: determine size, legality. */
-#ifdef notdef
-    if (exp[0] == '.' && exp[1] == '*') exp += 2;  /* aid grep */
-#endif
-    regparse = (char *)exp;
-    regnpar = 1;
-    regsize = 0L;
-    regcode = &regdummy;
-    regc(MAGIC);
-    if (reg(0, &flags) == NULL)
-        return(NULL);
-
-    /* Small enough for pointer-storage convention? */
-    if (regsize >= 32767L)      /* Probably could be 65535L. */
-        FAIL("regexp too big");
-
-    /* Allocate space. */
-    r = (regexp *)BJAM_MALLOC(sizeof(regexp) + (unsigned)regsize);
-    if (r == NULL)
-        FAIL("out of space");
-
-    /* Second pass: emit code. */
-    regparse = (char *)exp;
-    regnpar = 1;
-    regcode = r->program;
-    regc(MAGIC);
-    if (reg(0, &flags) == NULL)
-        return(NULL);
-
-    /* Dig out information for optimizations. */
-    r->regstart = '\0'; /* Worst-case defaults. */
-    r->reganch = 0;
-    r->regmust = NULL;
-    r->regmlen = 0;
-    scan = r->program+1;            /* First BRANCH. */
-    if (OP(regnext(scan)) == END) {     /* Only one top-level choice. */
-        scan = OPERAND(scan);
-
-        /* Starting-point info. */
-        if (OP(scan) == EXACTLY)
-            r->regstart = *OPERAND(scan);
-        else if (OP(scan) == BOL)
-            r->reganch++;
-
-        /*
-         * If there's something expensive in the r.e., find the
-         * longest literal string that must appear and make it the
-         * regmust.  Resolve ties in favor of later strings, since
-         * the regstart check works with the beginning of the r.e.
-         * and avoiding duplication strengthens checking.  Not a
-         * strong reason, but sufficient in the absence of others.
-         */
-        if (flags&SPSTART) {
-            longest = NULL;
-            len = 0;
-            for (; scan != NULL; scan = regnext(scan))
-                if (OP(scan) == EXACTLY && strlen(OPERAND(scan)) >= len) {
-                    longest = OPERAND(scan);
-                    len = strlen(OPERAND(scan));
-                }
-            r->regmust = longest;
-            r->regmlen = len;
-        }
-    }
-
-    return(r);
-}
-
-/*
- - reg - regular expression, i.e. main body or parenthesized thing
- *
- * Caller must absorb opening parenthesis.
- *
- * Combining parenthesis handling with the base level of regular expression
- * is a trifle forced, but the need to tie the tails of the branches to what
- * follows makes it hard to avoid.
- */
-static char *
-reg(
-    int paren,          /* Parenthesized? */
-    int *flagp )
-{
-    register char *ret;
-    register char *br;
-    register char *ender;
-    register int parno = 0;
-    int flags;
-
-    *flagp = HASWIDTH;  /* Tentatively. */
-
-    /* Make an OPEN node, if parenthesized. */
-    if (paren) {
-        if (regnpar >= NSUBEXP)
-            FAIL("too many ()");
-        parno = regnpar;
-        regnpar++;
-        ret = regnode(OPEN+parno);
-    } else
-        ret = NULL;
-
-    /* Pick up the branches, linking them together. */
-    br = regbranch(&flags);
-    if (br == NULL)
-        return(NULL);
-    if (ret != NULL)
-        regtail(ret, br);   /* OPEN -> first. */
-    else
-        ret = br;
-    if (!(flags&HASWIDTH))
-        *flagp &= ~HASWIDTH;
-    *flagp |= flags&SPSTART;
-    while (*regparse == '|' || *regparse == '\n') {
-        regparse++;
-        br = regbranch(&flags);
-        if (br == NULL)
-            return(NULL);
-        regtail(ret, br);   /* BRANCH -> BRANCH. */
-        if (!(flags&HASWIDTH))
-            *flagp &= ~HASWIDTH;
-        *flagp |= flags&SPSTART;
-    }
-
-    /* Make a closing node, and hook it on the end. */
-    ender = regnode((paren) ? CLOSE+parno : END);
-    regtail(ret, ender);
-
-    /* Hook the tails of the branches to the closing node. */
-    for (br = ret; br != NULL; br = regnext(br))
-        regoptail(br, ender);
-
-    /* Check for proper termination. */
-    if (paren && *regparse++ != ')') {
-        FAIL("unmatched ()");
-    } else if (!paren && *regparse != '\0') {
-        if (*regparse == ')') {
-            FAIL("unmatched ()");
-        } else
-            FAIL("junk on end");    /* "Can't happen". */
-        /* NOTREACHED */
-    }
-
-    return(ret);
-}
-
-/*
- - regbranch - one alternative of an | operator
- *
- * Implements the concatenation operator.
- */
-static char *
-regbranch( int *flagp )
-{
-    register char *ret;
-    register char *chain;
-    register char *latest;
-    int flags;
-
-    *flagp = WORST;     /* Tentatively. */
-
-    ret = regnode(BRANCH);
-    chain = NULL;
-    while (*regparse != '\0' && *regparse != ')' &&
-           *regparse != '\n' && *regparse != '|') {
-        latest = regpiece(&flags);
-        if (latest == NULL)
-            return(NULL);
-        *flagp |= flags&HASWIDTH;
-        if (chain == NULL)  /* First piece. */
-            *flagp |= flags&SPSTART;
-        else
-            regtail(chain, latest);
-        chain = latest;
-    }
-    if (chain == NULL)  /* Loop ran zero times. */
-        (void) regnode(NOTHING);
-
-    return(ret);
-}
-
-/*
- - regpiece - something followed by possible [*+?]
- *
- * Note that the branching code sequences used for ? and the general cases
- * of * and + are somewhat optimized:  they use the same NOTHING node as
- * both the endmarker for their branch list and the body of the last branch.
- * It might seem that this node could be dispensed with entirely, but the
- * endmarker role is not redundant.
- */
-static char *
-regpiece( int *flagp )
-{
-    register char *ret;
-    register char op;
-    register char *next;
-    int flags;
-
-    ret = regatom(&flags);
-    if (ret == NULL)
-        return(NULL);
-
-    op = *regparse;
-    if (!ISMULT(op)) {
-        *flagp = flags;
-        return(ret);
-    }
-
-    if (!(flags&HASWIDTH) && op != '?')
-        FAIL("*+ operand could be empty");
-    *flagp = (op != '+') ? (WORST|SPSTART) : (WORST|HASWIDTH);
-
-    if (op == '*' && (flags&SIMPLE))
-        reginsert(STAR, ret);
-    else if (op == '*') {
-        /* Emit x* as (x&|), where & means "self". */
-        reginsert(BRANCH, ret);         /* Either x */
-        regoptail(ret, regnode(BACK));      /* and loop */
-        regoptail(ret, ret);            /* back */
-        regtail(ret, regnode(BRANCH));      /* or */
-        regtail(ret, regnode(NOTHING));     /* null. */
-    } else if (op == '+' && (flags&SIMPLE))
-        reginsert(PLUS, ret);
-    else if (op == '+') {
-        /* Emit x+ as x(&|), where & means "self". */
-        next = regnode(BRANCH);         /* Either */
-        regtail(ret, next);
-        regtail(regnode(BACK), ret);        /* loop back */
-        regtail(next, regnode(BRANCH));     /* or */
-        regtail(ret, regnode(NOTHING));     /* null. */
-    } else if (op == '?') {
-        /* Emit x? as (x|) */
-        reginsert(BRANCH, ret);         /* Either x */
-        regtail(ret, regnode(BRANCH));      /* or */
-        next = regnode(NOTHING);        /* null. */
-        regtail(ret, next);
-        regoptail(ret, next);
-    }
-    regparse++;
-    if (ISMULT(*regparse))
-        FAIL("nested *?+");
-
-    return(ret);
-}
-
-/*
- - regatom - the lowest level
- *
- * Optimization:  gobbles an entire sequence of ordinary characters so that
- * it can turn them into a single node, which is smaller to store and
- * faster to run.  Backslashed characters are exceptions, each becoming a
- * separate node; the code is simpler that way and it's not worth fixing.
- */
-static char *
-regatom( int *flagp )
-{
-    register char *ret;
-    int flags;
-
-    *flagp = WORST;     /* Tentatively. */
-
-    switch (*regparse++) {
-    /* FIXME: these chars only have meaning at beg/end of pat? */
-    case '^':
-        ret = regnode(BOL);
-        break;
-    case '$':
-        ret = regnode(EOL);
-        break;
-    case '.':
-        ret = regnode(ANY);
-        *flagp |= HASWIDTH|SIMPLE;
-        break;
-    case '[': {
-            register int classr;
-            register int classend;
-
-            if (*regparse == '^') { /* Complement of range. */
-                ret = regnode(ANYBUT);
-                regparse++;
-            } else
-                ret = regnode(ANYOF);
-            if (*regparse == ']' || *regparse == '-')
-                regc(*regparse++);
-            while (*regparse != '\0' && *regparse != ']') {
-                if (*regparse == '-') {
-                    regparse++;
-                    if (*regparse == ']' || *regparse == '\0')
-                        regc('-');
-                    else {
-                        classr = UCHARAT(regparse-2)+1;
-                        classend = UCHARAT(regparse);
-                        if (classr > classend+1)
-                            FAIL("invalid [] range");
-                        for (; classr <= classend; classr++)
-                            regc(classr);
-                        regparse++;
-                    }
-                } else
-                    regc(*regparse++);
-            }
-            regc('\0');
-            if (*regparse != ']')
-                FAIL("unmatched []");
-            regparse++;
-            *flagp |= HASWIDTH|SIMPLE;
-        }
-        break;
-    case '(':
-        ret = reg(1, &flags);
-        if (ret == NULL)
-            return(NULL);
-        *flagp |= flags&(HASWIDTH|SPSTART);
-        break;
-    case '\0':
-    case '|':
-    case '\n':
-    case ')':
-        FAIL("internal urp");   /* Supposed to be caught earlier. */
-        break;
-    case '?':
-    case '+':
-    case '*':
-        FAIL("?+* follows nothing");
-        break;
-    case '\\':
-        switch (*regparse++) {
-        case '\0':
-            FAIL("trailing \\");
-            break;
-        case '<':
-            ret = regnode(WORDA);
-            break;
-        case '>':
-            ret = regnode(WORDZ);
-            break;
-        /* FIXME: Someday handle \1, \2, ... */
-        default:
-            /* Handle general quoted chars in exact-match routine */
-            goto de_fault;
-        }
-        break;
-    de_fault:
-    default:
-        /*
-         * Encode a string of characters to be matched exactly.
-         *
-         * This is a bit tricky due to quoted chars and due to
-         * '*', '+', and '?' taking the SINGLE char previous
-         * as their operand.
-         *
-         * On entry, the char at regparse[-1] is going to go
-         * into the string, no matter what it is.  (It could be
-         * following a \ if we are entered from the '\' case.)
-         *
-         * Basic idea is to pick up a good char in  ch  and
-         * examine the next char.  If it's *+? then we twiddle.
-         * If it's \ then we frozzle.  If it's other magic char
-         * we push  ch  and terminate the string.  If none of the
-         * above, we push  ch  on the string and go around again.
-         *
-         *  regprev  is used to remember where "the current char"
-         * starts in the string, if due to a *+? we need to back
-         * up and put the current char in a separate, 1-char, string.
-         * When  regprev  is NULL,  ch  is the only char in the
-         * string; this is used in *+? handling, and in setting
-         * flags |= SIMPLE at the end.
-         */
-        {
-            char *regprev;
-            register char ch;
-
-            regparse--;         /* Look at cur char */
-            ret = regnode(EXACTLY);
-            for ( regprev = 0 ; ; ) {
-                ch = *regparse++;   /* Get current char */
-                switch (*regparse) {    /* look at next one */
-
-                default:
-                    regc(ch);   /* Add cur to string */
-                    break;
-
-                case '.': case '[': case '(':
-                case ')': case '|': case '\n':
-                case '$': case '^':
-                case '\0':
-                /* FIXME, $ and ^ should not always be magic */
-                magic:
-                    regc(ch);   /* dump cur char */
-                    goto done;  /* and we are done */
-
-                case '?': case '+': case '*':
-                    if (!regprev)   /* If just ch in str, */
-                        goto magic; /* use it */
-                    /* End mult-char string one early */
-                    regparse = regprev; /* Back up parse */
-                    goto done;
-
-                case '\\':
-                    regc(ch);   /* Cur char OK */
-                    switch (regparse[1]){ /* Look after \ */
-                    case '\0':
-                    case '<':
-                    case '>':
-                    /* FIXME: Someday handle \1, \2, ... */
-                        goto done; /* Not quoted */
-                    default:
-                        /* Backup point is \, scan                           * point is after it. */
-                        regprev = regparse;
-                        regparse++;
-                        continue;   /* NOT break; */
-                    }
-                }
-                regprev = regparse; /* Set backup point */
-            }
-        done:
-            regc('\0');
-            *flagp |= HASWIDTH;
-            if (!regprev)       /* One char? */
-                *flagp |= SIMPLE;
-        }
-        break;
-    }
-
-    return(ret);
-}
-
-/*
- - regnode - emit a node
- */
-static char *           /* Location. */
-regnode( int op )
-{
-    register char *ret;
-    register char *ptr;
-
-    ret = regcode;
-    if (ret == &regdummy) {
-        regsize += 3;
-        return(ret);
-    }
-
-    ptr = ret;
-    *ptr++ = op;
-    *ptr++ = '\0';      /* Null "next" pointer. */
-    *ptr++ = '\0';
-    regcode = ptr;
-
-    return(ret);
-}
-
-/*
- - regc - emit (if appropriate) a byte of code
- */
-static void
-regc( int b )
-{
-    if (regcode != &regdummy)
-        *regcode++ = b;
-    else
-        regsize++;
-}
-
-/*
- - reginsert - insert an operator in front of already-emitted operand
- *
- * Means relocating the operand.
- */
-static void
-reginsert(
-    char op,
-    char *opnd )
-{
-    register char *src;
-    register char *dst;
-    register char *place;
-
-    if (regcode == &regdummy) {
-        regsize += 3;
-        return;
-    }
-
-    src = regcode;
-    regcode += 3;
-    dst = regcode;
-    while (src > opnd)
-        *--dst = *--src;
-
-    place = opnd;       /* Op node, where operand used to be. */
-    *place++ = op;
-    *place++ = '\0';
-    *place++ = '\0';
-}
-
-/*
- - regtail - set the next-pointer at the end of a node chain
- */
-static void
-regtail(
-    char *p,
-    char *val )
-{
-    register char *scan;
-    register char *temp;
-    register int offset;
-
-    if (p == &regdummy)
-        return;
-
-    /* Find last node. */
-    scan = p;
-    for (;;) {
-        temp = regnext(scan);
-        if (temp == NULL)
-            break;
-        scan = temp;
-    }
-
-    if (OP(scan) == BACK)
-        offset = scan - val;
-    else
-        offset = val - scan;
-    *(scan+1) = (offset>>8)&0377;
-    *(scan+2) = offset&0377;
-}
-
-/*
- - regoptail - regtail on operand of first argument; nop if operandless
- */
-
-static void
-regoptail(
-    char *p,
-    char *val )
-{
-    /* "Operandless" and "op != BRANCH" are synonymous in practice. */
-    if (p == NULL || p == &regdummy || OP(p) != BRANCH)
-        return;
-    regtail(OPERAND(p), val);
-}
-
-/*
- * regexec and friends
- */
-
-/*
- * Global work variables for regexec().
- */
-static char *reginput;      /* String-input pointer. */
-static char *regbol;        /* Beginning of input, for ^ check. */
-static char **regstartp;    /* Pointer to startp array. */
-static char **regendp;      /* Ditto for endp. */
-
-/*
- * Forwards.
- */
-STATIC int regtry( regexp *prog, char *string );
-STATIC int regmatch( char *prog );
-STATIC int regrepeat( char *p );
-
-#ifdef DEBUG
-int regnarrate = 0;
-void regdump();
-STATIC char *regprop();
-#endif
-
-/*
- - regexec - match a regexp against a string
- */
-int
-regexec(
-    register regexp *prog,
-    register char *string )
-{
-    register char *s;
-
-    /* Be paranoid... */
-    if (prog == NULL || string == NULL) {
-        regerror("NULL parameter");
-        return(0);
-    }
-
-    /* Check validity of program. */
-    if (UCHARAT(prog->program) != MAGIC) {
-        regerror("corrupted program");
-        return(0);
-    }
-
-    /* If there is a "must appear" string, look for it. */
-    if ( prog->regmust != NULL )
-    {
-        s = (char *)string;
-        while ( ( s = strchr( s, prog->regmust[ 0 ] ) ) != NULL )
-        {
-            if ( !strncmp( s, prog->regmust, prog->regmlen ) )
-                break;  /* Found it. */
-            ++s;
-        }
-        if ( s == NULL )  /* Not present. */
-            return 0;
-    }
-
-    /* Mark beginning of line for ^ . */
-    regbol = (char *)string;
-
-    /* Simplest case:  anchored match need be tried only once. */
-    if ( prog->reganch )
-        return regtry( prog, string );
-
-    /* Messy cases:  unanchored match. */
-    s = (char *)string;
-    if (prog->regstart != '\0')
-        /* We know what char it must start with. */
-        while ((s = strchr(s, prog->regstart)) != NULL) {
-            if (regtry(prog, s))
-                return(1);
-            s++;
-        }
-    else
-        /* We do not -- general case. */
-        do {
-            if ( regtry( prog, s ) )
-                return( 1 );
-        } while ( *s++ != '\0' );
-
-    /* Failure. */
-    return 0;
-}
-
-
-/*
- * regtry() - try match at specific point.
- */
-
-static int          /* 0 failure, 1 success */
-regtry(
-    regexp *prog,
-    char *string )
-{
-    register int i;
-    register char * * sp;
-    register char * * ep;
-
-    reginput = string;
-    regstartp = prog->startp;
-    regendp = prog->endp;
-
-    sp = prog->startp;
-    ep = prog->endp;
-    for ( i = NSUBEXP; i > 0; --i )
-    {
-        *sp++ = NULL;
-        *ep++ = NULL;
-    }
-    if ( regmatch( prog->program + 1 ) )
-    {
-        prog->startp[ 0 ] = string;
-        prog->endp[ 0 ] = reginput;
-        return 1;
-    }
-    else
-        return 0;
-}
-
-
-/*
- * regmatch() - main matching routine.
- *
- * Conceptually the strategy is simple: check to see whether the current node
- * matches, call self recursively to see whether the rest matches, and then act
- * accordingly. In practice we make some effort to avoid recursion, in
- * particular by going through "ordinary" nodes (that do not need to know
- * whether the rest of the match failed) by a loop instead of by recursion.
- */
-
-static int          /* 0 failure, 1 success */
-regmatch( char * prog )
-{
-    char * scan;  /* Current node. */
-    char * next;  /* Next node. */
-
-    scan = prog;
-#ifdef DEBUG
-    if (scan != NULL && regnarrate)
-        fprintf(stderr, "%s(\n", regprop(scan));
-#endif
-    while (scan != NULL) {
-#ifdef DEBUG
-        if (regnarrate)
-            fprintf(stderr, "%s...\n", regprop(scan));
-#endif
-        next = regnext(scan);
-
-        switch (OP(scan)) {
-        case BOL:
-            if (reginput != regbol)
-                return(0);
-            break;
-        case EOL:
-            if (*reginput != '\0')
-                return(0);
-            break;
-        case WORDA:
-            /* Must be looking at a letter, digit, or _ */
-            if ((!isalnum(*reginput)) && *reginput != '_')
-                return(0);
-            /* Prev must be BOL or nonword */
-            if (reginput > regbol &&
-                (isalnum(reginput[-1]) || reginput[-1] == '_'))
-                return(0);
-            break;
-        case WORDZ:
-            /* Must be looking at non letter, digit, or _ */
-            if (isalnum(*reginput) || *reginput == '_')
-                return(0);
-            /* We don't care what the previous char was */
-            break;
-        case ANY:
-            if (*reginput == '\0')
-                return(0);
-            reginput++;
-            break;
-        case EXACTLY: {
-                register int len;
-                register char *opnd;
-
-                opnd = OPERAND(scan);
-                /* Inline the first character, for speed. */
-                if (*opnd != *reginput)
-                    return(0);
-                len = strlen(opnd);
-                if (len > 1 && strncmp(opnd, reginput, len) != 0)
-                    return(0);
-                reginput += len;
-            }
-            break;
-        case ANYOF:
-            if (*reginput == '\0' || strchr(OPERAND(scan), *reginput) == NULL)
-                return(0);
-            reginput++;
-            break;
-        case ANYBUT:
-            if (*reginput == '\0' || strchr(OPERAND(scan), *reginput) != NULL)
-                return(0);
-            reginput++;
-            break;
-        case NOTHING:
-            break;
-        case BACK:
-            break;
-        case OPEN+1:
-        case OPEN+2:
-        case OPEN+3:
-        case OPEN+4:
-        case OPEN+5:
-        case OPEN+6:
-        case OPEN+7:
-        case OPEN+8:
-        case OPEN+9: {
-                register int no;
-                register char *save;
-
-                no = OP(scan) - OPEN;
-                save = reginput;
-
-                if (regmatch(next)) {
-                    /*
-                     * Don't set startp if some later
-                     * invocation of the same parentheses
-                     * already has.
-                     */
-                    if (regstartp[no] == NULL)
-                        regstartp[no] = save;
-                    return(1);
-                } else
-                    return(0);
-            }
-            break;
-        case CLOSE+1:
-        case CLOSE+2:
-        case CLOSE+3:
-        case CLOSE+4:
-        case CLOSE+5:
-        case CLOSE+6:
-        case CLOSE+7:
-        case CLOSE+8:
-        case CLOSE+9: {
-                register int no;
-                register char *save;
-
-                no = OP(scan) - CLOSE;
-                save = reginput;
-
-                if (regmatch(next)) {
-                    /*
-                     * Don't set endp if some later
-                     * invocation of the same parentheses
-                     * already has.
-                     */
-                    if (regendp[no] == NULL)
-                        regendp[no] = save;
-                    return(1);
-                } else
-                    return(0);
-            }
-            break;
-        case BRANCH: {
-                register char *save;
-
-                if (OP(next) != BRANCH)     /* No choice. */
-                    next = OPERAND(scan);   /* Avoid recursion. */
-                else {
-                    do {
-                        save = reginput;
-                        if (regmatch(OPERAND(scan)))
-                            return(1);
-                        reginput = save;
-                        scan = regnext(scan);
-                    } while (scan != NULL && OP(scan) == BRANCH);
-                    return(0);
-                    /* NOTREACHED */
-                }
-            }
-            break;
-        case STAR:
-        case PLUS: {
-                register char nextch;
-                register int no;
-                register char *save;
-                register int min;
-
-                /*
-                 * Lookahead to avoid useless match attempts
-                 * when we know what character comes next.
-                 */
-                nextch = '\0';
-                if (OP(next) == EXACTLY)
-                    nextch = *OPERAND(next);
-                min = (OP(scan) == STAR) ? 0 : 1;
-                save = reginput;
-                no = regrepeat(OPERAND(scan));
-                while (no >= min) {
-                    /* If it could work, try it. */
-                    if (nextch == '\0' || *reginput == nextch)
-                        if (regmatch(next))
-                            return(1);
-                    /* Couldn't or didn't -- back up. */
-                    no--;
-                    reginput = save + no;
-                }
-                return(0);
-            }
-            break;
-        case END:
-            return(1);  /* Success! */
-            break;
-        default:
-            regerror("memory corruption");
-            return(0);
-            break;
-        }
-
-        scan = next;
-    }
-
-    /*
-     * We get here only if there's trouble -- normally "case END" is
-     * the terminating point.
-     */
-    regerror("corrupted pointers");
-    return(0);
-}
-
-/*
- - regrepeat - repeatedly match something simple, report how many
- */
-static int
-regrepeat( char *p )
-{
-    register int count = 0;
-    register char *scan;
-    register char *opnd;
-
-    scan = reginput;
-    opnd = OPERAND(p);
-    switch (OP(p)) {
-    case ANY:
-        count = strlen(scan);
-        scan += count;
-        break;
-    case EXACTLY:
-        while (*opnd == *scan) {
-            count++;
-            scan++;
-        }
-        break;
-    case ANYOF:
-        while (*scan != '\0' && strchr(opnd, *scan) != NULL) {
-            count++;
-            scan++;
-        }
-        break;
-    case ANYBUT:
-        while (*scan != '\0' && strchr(opnd, *scan) == NULL) {
-            count++;
-            scan++;
-        }
-        break;
-    default:        /* Oh dear.  Called inappropriately. */
-        regerror("internal foulup");
-        count = 0;  /* Best compromise. */
-        break;
-    }
-    reginput = scan;
-
-    return(count);
-}
-
-/*
- - regnext - dig the "next" pointer out of a node
- */
-static char *
-regnext( register char *p )
-{
-    register int offset;
-
-    if (p == &regdummy)
-        return(NULL);
-
-    offset = NEXT(p);
-    if (offset == 0)
-        return(NULL);
-
-    if (OP(p) == BACK)
-        return(p-offset);
-    else
-        return(p+offset);
-}
-
-#ifdef DEBUG
-
-STATIC char *regprop();
-
-/*
- - regdump - dump a regexp onto stdout in vaguely comprehensible form
- */
-void
-regdump( regexp *r )
-{
-    register char *s;
-    register char op = EXACTLY; /* Arbitrary non-END op. */
-    register char *next;
-
-
-    s = r->program + 1;
-    while (op != END) { /* While that wasn't END last time... */
-        op = OP(s);
-        printf("%2d%s", s-r->program, regprop(s));  /* Where, what. */
-        next = regnext(s);
-        if (next == NULL)       /* Next ptr. */
-            printf("(0)");
-        else
-            printf("(%d)", (s-r->program)+(next-s));
-        s += 3;
-        if (op == ANYOF || op == ANYBUT || op == EXACTLY) {
-            /* Literal string, where present. */
-            while (*s != '\0') {
-                putchar(*s);
-                s++;
-            }
-            s++;
-        }
-        putchar('\n');
-    }
-
-    /* Header fields of interest. */
-    if (r->regstart != '\0')
-        printf("start `%c' ", r->regstart);
-    if (r->reganch)
-        printf("anchored ");
-    if (r->regmust != NULL)
-        printf("must have \"%s\"", r->regmust);
-    printf("\n");
-}
-
-/*
- - regprop - printable representation of opcode
- */
-static char *
-regprop( char *op )
-{
-    register char *p;
-    static char buf[50];
-
-    (void) strcpy(buf, ":");
-
-    switch (OP(op)) {
-    case BOL:
-        p = "BOL";
-        break;
-    case EOL:
-        p = "EOL";
-        break;
-    case ANY:
-        p = "ANY";
-        break;
-    case ANYOF:
-        p = "ANYOF";
-        break;
-    case ANYBUT:
-        p = "ANYBUT";
-        break;
-    case BRANCH:
-        p = "BRANCH";
-        break;
-    case EXACTLY:
-        p = "EXACTLY";
-        break;
-    case NOTHING:
-        p = "NOTHING";
-        break;
-    case BACK:
-        p = "BACK";
-        break;
-    case END:
-        p = "END";
-        break;
-    case OPEN+1:
-    case OPEN+2:
-    case OPEN+3:
-    case OPEN+4:
-    case OPEN+5:
-    case OPEN+6:
-    case OPEN+7:
-    case OPEN+8:
-    case OPEN+9:
-        sprintf(buf+strlen(buf), "OPEN%d", OP(op)-OPEN);
-        p = NULL;
-        break;
-    case CLOSE+1:
-    case CLOSE+2:
-    case CLOSE+3:
-    case CLOSE+4:
-    case CLOSE+5:
-    case CLOSE+6:
-    case CLOSE+7:
-    case CLOSE+8:
-    case CLOSE+9:
-        sprintf(buf+strlen(buf), "CLOSE%d", OP(op)-CLOSE);
-        p = NULL;
-        break;
-    case STAR:
-        p = "STAR";
-        break;
-    case PLUS:
-        p = "PLUS";
-        break;
-    case WORDA:
-        p = "WORDA";
-        break;
-    case WORDZ:
-        p = "WORDZ";
-        break;
-    default:
-        regerror("corrupted opcode");
-        break;
-    }
-    if (p != NULL)
-        (void) strcat(buf, p);
-    return(buf);
-}
-#endif
-
-/*
- * The following is provided for those people who do not have strcspn() in
- * their C libraries.  They should get off their butts and do something
- * about it; at least one public-domain implementation of those (highly
- * useful) string routines has been published on Usenet.
- */
-#ifdef STRCSPN
-/*
- * strcspn - find length of initial segment of s1 consisting entirely
- * of characters not from s2
- */
-
-static int
-strcspn(
-    char *s1,
-    char *s2 )
-{
-    register char *scan1;
-    register char *scan2;
-    register int count;
-
-    count = 0;
-    for (scan1 = s1; *scan1 != '\0'; scan1++) {
-        for (scan2 = s2; *scan2 != '\0';)   /* ++ moved down. */
-            if (*scan1 == *scan2++)
-                return(count);
-        count++;
-    }
-    return(count);
-}
-#endif