/*      $OpenBSD: eval.c,v 1.81 2026/02/25 05:37:25 op Exp $    */
/*      $NetBSD: eval.c,v 1.7 1996/11/10 21:21:29 pk Exp $      */

/*
 * Copyright (c) 1989, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Ozan Yigit at York University.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/*
 * eval.c
 * Facility: m4 macro processor
 * by: oz
 */

#include <sys/types.h>
#include <err.h>
#include <errno.h>
#include <limits.h>
#include <unistd.h>
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <stddef.h>
#include <string.h>
#include <fcntl.h>
#include "mdef.h"
#include "stdd.h"
#include "extern.h"
#include "pathnames.h"

static void     dodefn(const char *);
static void     dopushdef(const char *, const char *);
static void     dodumpdef(const char *[], int);
static void     dotrace(const char *[], int, int);
static void     doifelse(const char *[], int);
static int      doinclude(const char *);
static int      dopaste(const char *);
static void     dochangequote(const char *[], int);
static void     dochangecom(const char *[], int);
static void     dom4wrap(const char *);
static void     dodivert(int);
static void     doundivert(const char *[], int);
static void     dosubstr(const char *[], int);
static void     map(char *, const char *, const char *, const char *);
static const char *handledash(char *, char *, const char *);
static void     expand_builtin(const char *[], int, int);
static void     expand_macro(const char *[], int);
static void     dump_one_def(const char *, struct macro_definition *);

unsigned long   expansion_id;

/*
 * eval - eval all macros and builtins calls
 *        argc - number of elements in argv.
 *        argv - element vector :
 *                      argv[0] = definition of a user
 *                                macro or NULL if built-in.
 *                      argv[1] = name of the macro or
 *                                built-in.
 *                      argv[2] = parameters to user-defined
 *                         .      macro or built-in.
 *                         .
 *
 * A call in the form of macro-or-builtin() will result in:
 *                      argv[0] = nullstr
 *                      argv[1] = macro-or-builtin
 *                      argv[2] = nullstr
 *
 * argc is 3 for macro-or-builtin() and 2 for macro-or-builtin
 */
void
eval(const char *argv[], int argc, int td, int is_traced)
{
        size_t mark = SIZE_MAX;

        expansion_id++;
        if (td & RECDEF)
                m4errx(1, "expanding recursive definition for %s.", argv[1]);
        if (is_traced)
                mark = trace(argv, argc, infile+ilevel);
        if (td == MACROTYPE)
                expand_macro(argv, argc);
        else
                expand_builtin(argv, argc, td);
        if (mark != SIZE_MAX)
                finish_trace(mark);
}

/*
 * expand_builtin - evaluate built-in macros.
 */
void
expand_builtin(const char *argv[], int argc, int td)
{
        int c, n;
        const char *errstr;
        int ac;
        static int sysval = 0;

#ifdef DEBUG
        printf("argc = %d\n", argc);
        for (n = 0; n < argc; n++)
                printf("argv[%d] = %s\n", n, argv[n]);
        fflush(stdout);
#endif

 /*
  * if argc == 3 and argv[2] is null, then we
  * have macro-or-builtin() type call. We adjust
  * argc to avoid further checking..
  */
 /* we keep the initial value for those built-ins that differentiate
  * between builtin() and builtin.
  */
        ac = argc;

        if (argc == 3 && !*(argv[2]) && !mimic_gnu)
                argc--;

        switch (td & TYPEMASK) {

        case DEFINETYPE:
                if (argc > 2)
                        dodefine(argv[2], (argc > 3) ? argv[3] : null);
                break;

        case PUSHDEFTYPE:
                if (argc > 2)
                        dopushdef(argv[2], (argc > 3) ? argv[3] : null);
                break;

        case DUMPDEFTYPE:
                dodumpdef(argv, argc);
                break;

        case TRACEONTYPE:
                dotrace(argv, argc, 1);
                break;

        case TRACEOFFTYPE:
                dotrace(argv, argc, 0);
                break;

        case EVALTYPE:
        /*
         * doeval - evaluate arithmetic expression
         */
        {
                int base = 10;
                int maxdigits = 0;

                if (argc > 3) {
                        base = strtonum(argv[3], 2, 36, &errstr);
                        if (errstr) {
                                m4errx(1, "eval: base is %s: %s.", 
                                    errstr, argv[3]);
                        }
                }
                if (argc > 4) {
                        maxdigits = strtonum(argv[4], 0, INT_MAX, &errstr);
                        if (errstr) {
                                m4errx(1, "eval: maxdigits is %s: %s.", 
                                    errstr, argv[4]);
                        }
                }
                if (argc > 2)
                        pbnumbase(expr(argv[2]), base, maxdigits);
                break;
        }

        case IFELSETYPE:
                doifelse(argv, argc);
                break;

        case IFDEFTYPE:
        /*
         * doifdef - select one of two alternatives based 
         * on the existence of another definition
         */
                if (argc > 3) {
                        if (lookup_macro_definition(argv[2]) != NULL)
                                pbstr(argv[3]);
                        else if (argc > 4)
                                pbstr(argv[4]);
                }
                break;

        case LENTYPE:
        /*
         * dolen - find the length of the argument
         */
                pbnum((argc > 2) ? strlen(argv[2]) : 0);
                break;

        case INCRTYPE:
        /*
         * doincr - increment the value of the argument
         */
                if (argc > 2) {
                        n = strtonum(argv[2], INT_MIN, INT_MAX-1, &errstr);
                        if (errstr != NULL)
                                m4errx(1, "incr: argument is %s: %s.",
                                    errstr, argv[2]);
                        pbnum(n + 1);
                }
                break;

        case DECRTYPE:
        /*
         * dodecr - decrement the value of the argument
         */
                if (argc > 2) {
                        n = strtonum(argv[2], INT_MIN+1, INT_MAX, &errstr);
                        if (errstr)
                                m4errx(1, "decr: argument is %s: %s.",
                                    errstr, argv[2]);
                        pbnum(n - 1);
                }
                break;

        case SYSCMDTYPE:
        /*
         * dosyscmd - execute system command
         */
                if (argc > 2) {
                        fflush(stdout);
                        sysval = system(argv[2]);
                }
                break;

        case SYSVALTYPE:
        /*
         * dosysval - return value of the last system call.
         *
         */
                pbnum(sysval);
                break;

        case ESYSCMDTYPE:
                if (argc > 2)
                        doesyscmd(argv[2]);
                break;
        case INCLUDETYPE:
                if (argc > 2) {
                        if (!doinclude(argv[2])) {
                                if (mimic_gnu) {
                                        warn("%s at line %lu: include(%s)",
                                            CURRENT_NAME, CURRENT_LINE, argv[2]);
                                        exit_code = 1;
                                        if (fatal_warns) {
                                                killdiv();
                                                exit(exit_code);
                                        }
                                } else
                                        err(1, "%s at line %lu: include(%s)",
                                            CURRENT_NAME, CURRENT_LINE, argv[2]);
                        }
                }
                break;

        case SINCLUDETYPE:
        /* like include, but don't error out if file not found */
                if (argc > 2)
                        (void) doinclude(argv[2]);
                break;
#ifdef EXTENDED
        case PASTETYPE:
                if (argc > 2)
                        if (!dopaste(argv[2]))
                                err(1, "%s at line %lu: paste(%s)", 
                                    CURRENT_NAME, CURRENT_LINE, argv[2]);
                break;

        case SPASTETYPE:
                if (argc > 2)
                        (void) dopaste(argv[2]);
                break;
        case FORMATTYPE:
                doformat(argv, argc);
                break;
#endif
        case CHANGEQUOTETYPE:
                dochangequote(argv, ac);
                break;

        case CHANGECOMTYPE:
                dochangecom(argv, argc);
                break;

        case SUBSTRTYPE:
        /*
         * dosubstr - select substring
         *
         */
                if (argc > 3)
                        dosubstr(argv, argc);
                break;

        case SHIFTTYPE:
        /*
         * doshift - push back all arguments except the first one 
         * (i.e. skip argv[2])
         */
                if (argc > 3) {
                        for (n = argc - 1; n > 3; n--) {
                                pbstr(rquote);
                                pbstr(argv[n]);
                                pbstr(lquote);
                                pushback(COMMA);
                        }
                        pbstr(rquote);
                        pbstr(argv[3]);
                        pbstr(lquote);
                }
                break;

        case DIVERTTYPE:
                if (argc > 2) {
                        n = strtonum(argv[2], INT_MIN, INT_MAX, &errstr);
                        if (errstr)
                                m4errx(1, "divert: argument is %s: %s.", 
                                    errstr, argv[2]);
                        if (n != 0) {
                                dodivert(n);
                                break;
                        }
                }
                active = stdout;
                oindex = 0;
                break;

        case UNDIVERTTYPE:
                doundivert(argv, argc);
                break;

        case DIVNUMTYPE:
        /*
         * dodivnum - return the number of current output diversion
         */
                pbnum(oindex);
                break;

        case UNDEFINETYPE:
        /*
         * doundefine - undefine a previously defined macro(s) or m4 keyword(s).
         */
                if (argc > 2)
                        for (n = 2; n < argc; n++)
                                macro_undefine(argv[n]);
                break;

        case POPDEFTYPE:
        /*
         * dopopdef - remove the topmost definitions of macro(s) 
         * or m4 keyword(s).
         */
                if (argc > 2)
                        for (n = 2; n < argc; n++)
                                macro_popdef(argv[n]);
                break;

        case MKSTEMPTYPE:
        /*
         * domkstemp - safely create a temporary file
         */
                if (argc > 2) {
                        int fd;
                        char *temp;

                        temp = xstrdup(argv[2]);

                        fd = mkstemp(temp);
                        if (fd == -1)
                                err(1,
            "%s at line %lu: couldn't make temp file %s",
            CURRENT_NAME, CURRENT_LINE, argv[2]);
                        close(fd);
                        pbstr(temp);
                        free(temp);
                }
                break;

        case TRANSLITTYPE:
        /*
         * dotranslit - replace all characters in the source string 
         * that appear in the "from" string with the corresponding
         * characters in the "to" string.
         */
                if (argc > 3) {
                        char *temp;

                        temp = xalloc(strlen(argv[2])+1, NULL);
                        if (argc > 4)
                                map(temp, argv[2], argv[3], argv[4]);
                        else
                                map(temp, argv[2], argv[3], null);
                        pbstr(temp);
                        free(temp);
                } else if (argc > 2)
                        pbstr(argv[2]);
                break;

        case INDEXTYPE:
        /*
         * doindex - find the index of the second argument string 
         * in the first argument string. -1 if not present.
         */
                pbnum((argc > 3) ? doindex(argv[2], argv[3]) : -1);
                break;

        case ERRPRINTTYPE:
        /*
         * doerrprint - print the arguments to stderr
         */
                if (argc > 2) {
                        for (n = 2; n < argc; n++)
                                fprintf(stderr, "%s ", argv[n]);
                        fprintf(stderr, "\n");
                }
                break;

        case DNLTYPE:
        /*
         * dodnl - eat-up-to and including newline
         */
                while ((c = gpbc()) != '\n' && c != EOF)
                        ;
                break;

        case M4WRAPTYPE:
        /*
         * dom4wrap - set up for
         * wrap-up/wind-down activity
         */
                if (argc > 2)
                        dom4wrap(argv[2]);
                break;

        case M4EXITTYPE:
        /*
         * dom4exit - immediate exit from m4.
         */
                killdiv();
                exit((argc > 2) ? atoi(argv[2]) : 0);
                break;

        case DEFNTYPE:
                if (argc > 2)
                        for (n = 2; n < argc; n++)
                                dodefn(argv[n]);
                break;

        case INDIRTYPE: /* Indirect call */
                if (argc > 2)
                        doindir(argv, argc);
                break;

        case BUILTINTYPE: /* Builtins only */
                if (argc > 2)
                        dobuiltin(argv, argc);
                break;

        case PATSUBSTTYPE:
                if (argc > 2)
                        dopatsubst(argv, argc);
                break;
        case REGEXPTYPE:
                if (argc > 2)
                        doregexp(argv, argc);
                break;
        case LINETYPE:
                doprintlineno(infile+ilevel);
                break;
        case FILENAMETYPE:
                doprintfilename(infile+ilevel);
                break;
        case SELFTYPE:
                pbstr(rquote);
                pbstr(argv[1]);
                pbstr(lquote);
                break;
        default:
                m4errx(1, "eval: major botch.");
                break;
        }
}

/*
 * expand_macro - user-defined macro expansion
 */
void
expand_macro(const char *argv[], int argc)
{
        const char *t;
        const char *p;
        int n;
        int argno;

        t = argv[0];                   /* defn string as a whole */
        p = t;
        while (*p)
                p++;
        p--;                           /* last character of defn */
        while (p > t) {
                if (*(p - 1) != ARGFLAG)
                        PUSHBACK(*p);
                else {
                        switch (*p) {

                        case '#':
                                pbnum(argc - 2);
                                break;
                        case '0':
                        case '1':
                        case '2':
                        case '3':
                        case '4':
                        case '5':
                        case '6':
                        case '7':
                        case '8':
                        case '9':
                                if ((argno = *p - '0') < argc - 1)
                                        pbstr(argv[argno + 1]);
                                break;
                        case '*':
                                if (argc > 2) {
                                        for (n = argc - 1; n > 2; n--) {
                                                pbstr(argv[n]);
                                                pushback(COMMA);
                                        }
                                        pbstr(argv[2]);
                                }
                                break;
                        case '@':
                                if (argc > 2) {
                                        for (n = argc - 1; n > 2; n--) {
                                                pbstr(rquote);
                                                pbstr(argv[n]);
                                                pbstr(lquote);
                                                pushback(COMMA);
                                        }
                                        pbstr(rquote);
                                        pbstr(argv[2]);
                                        pbstr(lquote);
                                }
                                break;
                        default:
                                PUSHBACK(*p);
                                PUSHBACK('$');
                                break;
                        }
                        p--;
                }
                p--;
        }
        if (p == t)                    /* do last character */
                PUSHBACK(*p);
}


/*
 * dodefine - install definition in the table
 */
void
dodefine(const char *name, const char *defn)
{
        if (!*name && !mimic_gnu)
                m4errx(1, "define macro with empty name.");
        else
                macro_define(name, defn);
}

/*
 * dodefn - push back a quoted definition of
 *      the given name.
 */
static void
dodefn(const char *name)
{
        struct macro_definition *p;

        if ((p = lookup_macro_definition(name)) != NULL) {
                if ((p->type & TYPEMASK) == MACROTYPE) {
                        pbstr(rquote);
                        pbstr(p->defn);
                        pbstr(lquote);
                } else {
                        pbstr(p->defn);
                        pbstr(BUILTIN_MARKER);
                }
        }
}

/*
 * dopushdef - install a definition in the hash table
 *      without removing a previous definition. Since
 *      each new entry is entered in *front* of the
 *      hash bucket, it hides a previous definition from
 *      lookup.
 */
static void
dopushdef(const char *name, const char *defn)
{
        if (!*name && !mimic_gnu)
                m4errx(1, "pushdef macro with empty name.");
        else
                macro_pushdef(name, defn);
}

/*
 * dump_one_def - dump the specified definition.
 */
static void
dump_one_def(const char *name, struct macro_definition *p)
{
        if (!traceout)
                traceout = stderr;
        if (mimic_gnu) {
                if ((p->type & TYPEMASK) == MACROTYPE)
                        fprintf(traceout, "%s:\t%s\n", name, p->defn);
                else {
                        fprintf(traceout, "%s:\t<%s>\n", name, p->defn);
                }
        } else
                fprintf(traceout, "`%s'\t`%s'\n", name, p->defn);
}

/*
 * dodumpdef - dump the specified definitions in the hash
 *      table to stderr. If nothing is specified, the entire
 *      hash table is dumped.
 */
static void
dodumpdef(const char *argv[], int argc)
{
        int n;
        struct macro_definition *p;

        if (argc > 2) {
                for (n = 2; n < argc; n++)
                        if ((p = lookup_macro_definition(argv[n])) != NULL)
                                dump_one_def(argv[n], p);
        } else
                macro_for_all(dump_one_def);
}

/*
 * dotrace - mark some macros as traced/untraced depending upon on.
 */
static void
dotrace(const char *argv[], int argc, int on)
{
        int n;

        if (argc > 2) {
                for (n = 2; n < argc; n++)
                        mark_traced(argv[n], on);
        } else
                mark_traced(NULL, on);
}

/*
 * doifelse - select one of two alternatives - loop.
 */
static void
doifelse(const char *argv[], int argc)
{
        while (argc > 4) {
                if (STREQ(argv[2], argv[3])) {
                        pbstr(argv[4]);
                        break;
                } else if (argc == 6) {
                        pbstr(argv[5]);
                        break;
                } else {
                        argv += 3;
                        argc -= 3;
                }
        }
}

/*
 * doinclude - include a given file.
 */
static int
doinclude(const char *ifile)
{
        if (ilevel + 1 == MAXINP)
                m4errx(1, "too many include files.");
        if (fopen_trypath(infile+ilevel+1, ifile) != NULL) {
                ilevel++;
                bbase[ilevel] = bufbase = bp;
                return (1);
        } else
                return (0);
}

#ifdef EXTENDED
/*
 * dopaste - include a given file without any
 *           macro processing.
 */
static int
dopaste(const char *pfile)
{
        FILE *pf;
        int c;

        if ((pf = fopen(pfile, "r")) != NULL) {
                if (synch_lines)
                    fprintf(active, "#line 1 \"%s\"\n", pfile);
                while ((c = getc(pf)) != EOF)
                        putc(c, active);
                (void) fclose(pf);
                emit_synchline();
                return (1);
        } else
                return (0);
}
#endif

/*
 * dochangequote - change quote characters
 */
static void
dochangequote(const char *argv[], int ac)
{
        if (ac == 2) {
                lquote[0] = LQUOTE; lquote[1] = EOS;
                rquote[0] = RQUOTE; rquote[1] = EOS;
        } else {
                strlcpy(lquote, argv[2], sizeof(lquote));
                if (ac > 3) {
                        strlcpy(rquote, argv[3], sizeof(rquote));
                } else {
                        rquote[0] = ECOMMT; rquote[1] = EOS;
                }
        }
}

/*
 * dochangecom - change comment characters
 */
static void
dochangecom(const char *argv[], int argc)
{
/* XXX Note that there is no difference between no argument and a single
 * empty argument.
 */
        if (argc == 2) {
                scommt[0] = EOS;
                ecommt[0] = EOS;
        } else {
                strlcpy(scommt, argv[2], sizeof(scommt));
                if (argc == 3) {
                        ecommt[0] = ECOMMT; ecommt[1] = EOS;
                } else {
                        strlcpy(ecommt, argv[3], sizeof(ecommt));
                }
        }
}

/*
 * dom4wrap - expand text at EOF
 */
static void
dom4wrap(const char *text)
{
        if (wrapindex >= maxwraps) {
                if (maxwraps == 0)
                        maxwraps = 16;
                else
                        maxwraps *= 2;
                m4wraps = xreallocarray(m4wraps, maxwraps, sizeof(*m4wraps),
                   "too many m4wraps");
        }
        m4wraps[wrapindex++] = xstrdup(text);
}

/*
 * dodivert - divert the output to a temporary file
 */
static void
dodivert(int n)
{
        int fd;

        oindex = n;
        if (n >= maxout) {
                if (mimic_gnu)
                        resizedivs(n + 10);
                else
                        n = 0;          /* bitbucket */
        }

        if (n < 0)
                n = 0;                 /* bitbucket */
        if (outfile[n] == NULL) {
                char fname[] = _PATH_DIVNAME;

                if ((fd = mkstemp(fname)) == -1 ||
                    unlink(fname) == -1 ||
                    (outfile[n] = fdopen(fd, "w+")) == NULL)
                        err(1, "%s: cannot divert", fname);
        }
        active = outfile[n];
}

/*
 * doundivert - undivert a specified output, or all
 *              other outputs, in numerical order.
 */
static void
doundivert(const char *argv[], int argc)
{
        int ind;
        int n;

        if (argc > 2) {
                for (ind = 2; ind < argc; ind++) {
                        const char *errstr;
                        n = strtonum(argv[ind], 1, INT_MAX, &errstr);
                        if (errstr) {
                                if (errno == EINVAL && mimic_gnu)
                                        getdivfile(argv[ind]);
                        } else {
                                if (n < maxout && outfile[n] != NULL)
                                        getdiv(n);
                        }
                }
        }
        else
                for (n = 1; n < maxout; n++)
                        if (outfile[n] != NULL)
                                getdiv(n);
}

/*
 * dosubstr - select substring
 */
static void
dosubstr(const char *argv[], int argc)
{
        const char *ap, *fc, *k;
        int nc;

        ap = argv[2];                  /* target string */
#ifdef EXPR
        fc = ap + expr(argv[3]);       /* first char */
#else
        fc = ap + atoi(argv[3]);       /* first char */
#endif
        nc = strlen(fc);
        if (argc >= 5)
#ifdef EXPR
                nc = min(nc, expr(argv[4]));
#else
                nc = min(nc, atoi(argv[4]));
#endif
        if (fc >= ap && fc < ap + strlen(ap))
                for (k = fc + nc - 1; k >= fc; k--)
                        pushback(*k);
}

/*
 * map:
 * map every character of s1 that is specified in from
 * into s3 and replace in s. (source s1 remains untouched)
 *
 * This is derived from the a standard implementation of map(s,from,to) 
 * function of ICON language. Within mapvec, we replace every character 
 * of "from" with the corresponding character in "to". 
 * If "to" is shorter than "from", than the corresponding entries are null, 
 * which means that those characters disappear altogether. 
 */
static void
map(char *dest, const char *src, const char *from, const char *to)
{
        const char *tmp;
        unsigned char sch, dch;
        static char frombis[257];
        static char tobis[257];
        int i;
        char seen[256];
        static unsigned char mapvec[256] = {
            0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,
            19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,
            36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52,
            53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69,
            70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86,
            87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102,
            103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115,
            116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128,
            129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141,
            142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154,
            155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167,
            168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180,
            181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191, 192, 193,
            194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206,
            207, 208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219,
            220, 221, 222, 223, 224, 225, 226, 227, 228, 229, 230, 231, 232,
            233, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245,
            246, 247, 248, 249, 250, 251, 252, 253, 254, 255
        };

        if (*src) {
                if (mimic_gnu) {
                        /*
                         * expand character ranges on the fly
                         */
                        from = handledash(frombis, frombis + 256, from);
                        to = handledash(tobis, tobis + 256, to);
                }
                tmp = from;
        /*
         * create a mapping between "from" and
         * "to"
         */
                for (i = 0; i < 256; i++)
                        seen[i] = 0;
                while (*from) {
                        if (!seen[(unsigned char)(*from)]) {
                                mapvec[(unsigned char)(*from)] = (unsigned char)(*to);
                                seen[(unsigned char)(*from)] = 1;
                        }
                        from++;
                        if (*to)
                                to++;
                }

                while (*src) {
                        sch = (unsigned char)(*src++);
                        dch = mapvec[sch];
                        if ((*dest = (char)dch))
                                dest++;
                }
        /*
         * restore all the changed characters
         */
                while (*tmp) {
                        mapvec[(unsigned char)(*tmp)] = (unsigned char)(*tmp);
                        tmp++;
                }
        }
        *dest = '\0';
}


/*
 * handledash:
 *  use buffer to copy the src string, expanding character ranges
 * on the way.
 */
static const char *
handledash(char *buffer, char *end, const char *src)
{
        char *p;

        p = buffer;
        while(*src) {
                if (src[1] == '-' && src[2]) {
                        unsigned char i;
                        if ((unsigned char)src[0] <= (unsigned char)src[2]) {
                                for (i = (unsigned char)src[0]; 
                                    i <= (unsigned char)src[2]; i++) {
                                        *p++ = i;
                                        if (p == end) {
                                                *p = '\0';
                                                return buffer;
                                        }
                                }
                        } else {
                                for (i = (unsigned char)src[0]; 
                                    i >= (unsigned char)src[2]; i--) {
                                        *p++ = i;
                                        if (p == end) {
                                                *p = '\0';
                                                return buffer;
                                        }
                                }
                        }
                        src += 3;
                } else
                        *p++ = *src++;
                if (p == end)
                        break;
        }
        *p = '\0';
        return buffer;
}