Due to the license change I can now use Minix code. Minix tr

(adapted) now replaces BSD tr.  Goes from 5k to 1k, and eliminates
bsearch from the list of libc symbols.
 -Erik


git-svn-id: svn://busybox.net/trunk/busybox@513 69ca8d6d-28ef-0310-b511-8ec308f3f277

1 files changed, 190 insertions, 525 deletions

diff --git a/tr.c b/tr.c
index 5f4938028..079c252d3 100644
--- a/tr.c
+++ b/tr.c
@@ -1,574 +1,239 @@
 /* vi: set sw=4 ts=4: */
 /*
- * Copyright (c) 1988, 1993
- *      The Regents of the University of California.  All rights reserved.
+ * Mini tr implementation for busybox
  *
- * 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. All advertising materials mentioning features or use of this software
- *    must display the following acknowledgement:
- *      This product includes software developed by the University of
- *      California, Berkeley and its contributors.
- * 4. 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 version of tr is adapted from Minix tr
+ * Author: Michiel Huisjes
  *
- * 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.
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * 
+ * Original copyright notice is retained at the end of this file.
  */
 
-#if 0
-#ifndef lint
-static const char copyright[] = "@(#) Copyright (c) 1988, 1993\n\
-        The Regents of the University of California.  All rights reserved.\n";
-#endif                                                  /* not lint */
-
-#ifndef lint
-#if 0
-static char sccsid[] = "@(#)tr.c        8.2 (Berkeley) 5/4/95";
-#endif
-static const char rcsid[] =
-
-        "$Id: tr.c,v 1.4 2000/04/17 16:44:46 erik Exp $";
-#endif                                                  /* not lint */
-#endif                                                  /* #if 0 */
-
 #include "internal.h"
-#include <locale.h>
-#include <sys/types.h>
-#include <sys/cdefs.h>
-#include <sys/types.h>
-
-#include <err.h>
 #include <stdio.h>
-#include <stdlib.h>
 #include <string.h>
+#include <stdlib.h>
 #include <unistd.h>
+#include <sys/types.h>
 
-#include <ctype.h>
-#include <err.h>
-#include <stddef.h>
-
-typedef struct {
-        enum { STRING1, STRING2 } which;
-        enum { EOS, INFINITE, NORMAL, RANGE, SEQUENCE, SET } state;
-        int cnt;                                        /* character count */
-        int lastch;                                     /* last character */
-        int equiv[2];                           /* equivalence set */
-        int *set;                                       /* set of characters */
-        char *str;                                      /* user's string */
-} STR;
-
-#include <limits.h>
-#define NCHARS  (UCHAR_MAX + 1) /* Number of possible characters. */
-#define OOBCH   (UCHAR_MAX + 1) /* Out of band character value. */
-
-static int next __P((STR *));
-
-static int string1[NCHARS] = {
-        0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, /* ASCII */
-        0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
-        0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
-        0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
-        0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
-        0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
-        0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
-        0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
-        0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
-        0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
-        0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
-        0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,
-        0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
-        0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f,
-        0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,
-        0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f,
-        0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
-        0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
-        0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97,
-        0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f,
-        0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
-        0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf,
-        0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7,
-        0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf,
-        0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7,
-        0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf,
-        0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7,
-        0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf,
-        0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7,
-        0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef,
-        0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7,
-        0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff,
-}, string2[NCHARS];
-
-STR s1 = { STRING1, NORMAL, 0, OOBCH, {0, OOBCH}, NULL, NULL };
-STR s2 = { STRING2, NORMAL, 0, OOBCH, {0, OOBCH}, NULL, NULL };
 
-static void setup(string, arg, str, cflag)
-int *string;
-char *arg;
-STR *str;
-int cflag;
-{
-        register int cnt, *p;
 
-        str->str = arg;
-        bzero(string, NCHARS * sizeof(int));
+#ifdef TRUE
+#undef TRUE
+#undef FALSE
+#define TRUE    1
+#define FALSE   0
+#endif
 
-        while (next(str))
-                string[str->lastch] = 1;
-        if (cflag)
-                for (p = string, cnt = NCHARS; cnt--; ++p)
-                        *p = !*p;
-}
+#define ASCII           0377
 
-static void tr_usage()
-{
-        usage( "\ttr [-cdsu] string1 [string2]\n\n"
-                   "Translate, squeeze, and/or delete characters from standard\n"
-                   "input, writing to standard output.\n");
-}
+/* some glabals shared across this file */
+static char com_fl, del_fl, sq_fl;
+static unsigned char output[BUFSIZ], input[BUFSIZ];
+static unsigned char vector[ASCII + 1];
+static char invec[ASCII + 1], outvec[ASCII + 1];
+static short in_index, out_index;
 
 
-extern int tr_main(argc, argv)
-int argc;
-char **argv;
+static void convert()
 {
-        register int ch, cnt, lastch, *p;
-        int cflag, dflag, sflag, isstring2;
-
-        (void) setlocale(LC_CTYPE, "");
-
-        cflag = dflag = sflag = 0;
-        while ((ch = getopt(argc, argv, "cdsu")) != -1)
-                switch ((char) ch) {
-                case 'c':
-                        cflag = 1;
-                        break;
-                case 'd':
-                        dflag = 1;
-                        break;
-                case 's':
-                        sflag = 1;
-                        break;
-                case 'u':
-                        setbuf(stdout, (char *) NULL);
-                        break;
-                case '?':
-                default:
-                        tr_usage();
-                }
-        argc -= optind;
-        argv += optind;
-
-        switch (argc) {
-        case 0:
-        default:
-                tr_usage();
-                /* NOTREACHED */
-        case 1:
-                isstring2 = 0;
-                break;
-        case 2:
-                isstring2 = 1;
-                break;
-        }
-
-        /*
-         * tr -ds [-c] string1 string2
-         * Delete all characters (or complemented characters) in string1.
-         * Squeeze all characters in string2.
-         */
-        if (dflag && sflag) {
-                if (!isstring2)
-                        tr_usage();
-
-                setup(string1, argv[0], &s1, cflag);
-                setup(string2, argv[1], &s2, 0);
-
-                for (lastch = OOBCH; (ch = getchar()) != EOF;)
-                        if (!string1[ch] && (!string2[ch] || lastch != ch)) {
-                                lastch = ch;
-                                (void) putchar(ch);
+        short read_chars = 0;
+        short c, coded;
+        short last = -1;
+
+        for (;;) {
+                if (in_index == read_chars) {
+                        if ((read_chars = read(0, (char *) input, BUFSIZ)) <= 0) {
+                                if (write(1, (char *) output, out_index) != out_index)
+                                        write(2, "Bad write\n", 10);
+                                exit(0);
                         }
-                exit(0);
-        }
-
-        /*
-         * tr -d [-c] string1
-         * Delete all characters (or complemented characters) in string1.
-         */
-        if (dflag) {
-                if (isstring2)
-                        tr_usage();
-
-                setup(string1, argv[0], &s1, cflag);
-
-                while ((ch = getchar()) != EOF)
-                        if (!string1[ch])
-                                (void) putchar(ch);
-                exit(0);
-        }
-
-        /*
-         * tr -s [-c] string1
-         * Squeeze all characters (or complemented characters) in string1.
-         */
-        if (sflag && !isstring2) {
-                setup(string1, argv[0], &s1, cflag);
-
-                for (lastch = OOBCH; (ch = getchar()) != EOF;)
-                        if (!string1[ch] || lastch != ch) {
-                                lastch = ch;
-                                (void) putchar(ch);
-                        }
-                exit(0);
-        }
-
-        /*
-         * tr [-cs] string1 string2
-         * Replace all characters (or complemented characters) in string1 with
-         * the character in the same position in string2.  If the -s option is
-         * specified, squeeze all the characters in string2.
-         */
-        if (!isstring2)
-                tr_usage();
-
-        s1.str = argv[0];
-        s2.str = argv[1];
-
-        if (cflag)
-                for (cnt = NCHARS, p = string1; cnt--;)
-                        *p++ = OOBCH;
-
-        if (!next(&s2))
-                errx(1, "empty string2");
-
-        /* If string2 runs out of characters, use the last one specified. */
-        if (sflag)
-                while (next(&s1)) {
-                        string1[s1.lastch] = ch = s2.lastch;
-                        string2[ch] = 1;
-                        (void) next(&s2);
-        } else
-                while (next(&s1)) {
-                        string1[s1.lastch] = ch = s2.lastch;
-                        (void) next(&s2);
+                        in_index = 0;
                 }
-
-        if (cflag)
-                for (cnt = 0, p = string1; cnt < NCHARS; ++p, ++cnt)
-                        *p = *p == OOBCH ? ch : cnt;
-
-        if (sflag)
-                for (lastch = OOBCH; (ch = getchar()) != EOF;) {
-                        ch = string1[ch];
-                        if (!string2[ch] || lastch != ch) {
-                                lastch = ch;
-                                (void) putchar(ch);
+                c = input[in_index++];
+                coded = vector[c];
+                if (del_fl && invec[c])
+                        continue;
+                if (sq_fl && last == coded && outvec[coded])
+                        continue;
+                output[out_index++] = last = coded;
+                if (out_index == BUFSIZ) {
+                        if (write(1, (char *) output, out_index) != out_index) {
+                                write(2, "Bad write\n", 10);
+                                exit(1);
                         }
-        } else
-                while ((ch = getchar()) != EOF)
-                        (void) putchar(string1[ch]);
-        exit(0);
-}
-
-static int backslash __P((STR *));
-static int bracket __P((STR *));
-static int c_class __P((const void *, const void *));
-static void genclass __P((STR *));
-static void genequiv __P((STR *));
-static int genrange __P((STR *));
-static void genseq __P((STR *));
-
-static int next(s)
-register STR *s;
-{
-        register int ch;
-
-        switch (s->state) {
-        case EOS:
-                return (0);
-        case INFINITE:
-                return (1);
-        case NORMAL:
-                switch (ch = (u_char) * s->str) {
-                case '\0':
-                        s->state = EOS;
-                        return (0);
-                case '\\':
-                        s->lastch = backslash(s);
-                        break;
-                case '[':
-                        if (bracket(s))
-                                return (next(s));
-                        /* FALLTHROUGH */
-                default:
-                        ++s->str;
-                        s->lastch = ch;
-                        break;
-                }
-
-                /* We can start a range at any time. */
-                if (s->str[0] == '-' && genrange(s))
-                        return (next(s));
-                return (1);
-        case RANGE:
-                if (s->cnt-- == 0) {
-                        s->state = NORMAL;
-                        return (next(s));
-                }
-                ++s->lastch;
-                return (1);
-        case SEQUENCE:
-                if (s->cnt-- == 0) {
-                        s->state = NORMAL;
-                        return (next(s));
-                }
-                return (1);
-        case SET:
-                if ((s->lastch = s->set[s->cnt++]) == OOBCH) {
-                        s->state = NORMAL;
-                        return (next(s));
+                        out_index = 0;
                 }
-                return (1);
         }
-        /* NOTREACHED */
-        return (0);
-}
 
-static int bracket(s)
-register STR *s;
-{
-        register char *p;
-
-        switch (s->str[1]) {
-        case ':':                                       /* "[:class:]" */
-                if ((p = strstr(s->str + 2, ":]")) == NULL)
-                        return (0);
-                *p = '\0';
-                s->str += 2;
-                genclass(s);
-                s->str = p + 2;
-                return (1);
-        case '=':                                       /* "[=equiv=]" */
-                if ((p = strstr(s->str + 2, "=]")) == NULL)
-                        return (0);
-                s->str += 2;
-                genequiv(s);
-                return (1);
-        default:                                        /* "[\###*n]" or "[#*n]" */
-                if ((p = strpbrk(s->str + 2, "*]")) == NULL)
-                        return (0);
-                if (p[0] != '*' || index(p, ']') == NULL)
-                        return (0);
-                s->str += 1;
-                genseq(s);
-                return (1);
-        }
         /* NOTREACHED */
 }
 
-typedef struct {
-        char *name;
-        int (*func) __P((int));
-        int *set;
-} CLASS;
-
-static CLASS classes[] = {
-#undef isalnum
-        {"alnum", isalnum,},
-#undef isalpha
-        {"alpha", isalpha,},
-/*#undef isblank
-        { "blank",  isblank,  },*/
-#undef iscntrl
-        {"cntrl", iscntrl,},
-#undef isdigit
-        {"digit", isdigit,},
-#undef isgraph
-        {"graph", isgraph,},
-#undef islower
-        {"lower", islower,},
-#undef isprint
-        {"print", isprint,},
-#undef ispunct
-        {"punct", ispunct,},
-#undef isspace
-        {"space", isspace,},
-#undef isupper
-        {"upper", isupper,},
-#undef isxdigit
-        {"xdigit", isxdigit,},
-};
-
-static void genclass(s)
-STR *s;
+static void map(register unsigned char *string1, register unsigned char *string2)
 {
-        register int cnt, (*func) __P((int));
-        CLASS *cp, tmp;
-        int *p;
-
-        tmp.name = s->str;
-        if ((cp = (CLASS *) bsearch(&tmp, classes, sizeof(classes) /
-                                                                sizeof(CLASS), sizeof(CLASS),
-                                                                c_class)) == NULL) errx(1,
-                                                                                                                "unknown class %s",
-                                                                                                                s->str);
-
-        cp->set = p = xmalloc((NCHARS + 1) * sizeof(int));
-        bzero(p, (NCHARS + 1) * sizeof(int));
-
-        for (cnt = 0, func = cp->func; cnt < NCHARS; ++cnt)
-                if ((func) (cnt))
-                        *p++ = cnt;
-        *p = OOBCH;
-
-        s->cnt = 0;
-        s->state = SET;
-        s->set = cp->set;
-}
-
-static int c_class(a, b)
-const void *a, *b;
-{
-        return (strcmp(((CLASS *) a)->name, ((CLASS *) b)->name));
+        unsigned char last = '0';
+
+        while (*string1) {
+                if (*string2 == '\0')
+                        vector[*string1] = last;
+                else
+                        vector[*string1] = last = *string2++;
+                string1++;
+        }
 }
 
-/*
- * English doesn't have any equivalence classes, so for now
- * we just syntax check and grab the character.
- */
-static void genequiv(s)
-STR *s;
+static void expand(register char *arg, register unsigned char *buffer)
 {
-        if (*s->str == '\\') {
-                s->equiv[0] = backslash(s);
-                if (*s->str != '=')
-                        errx(1, "misplaced equivalence equals sign");
-        } else {
-                s->equiv[0] = s->str[0];
-                if (s->str[1] != '=')
-                        errx(1, "misplaced equivalence equals sign");
+        int i, ac;
+
+        while (*arg) {
+                if (*arg == '\\') {
+                        arg++;
+                        i = ac = 0;
+                        if (*arg >= '0' && *arg <= '7') {
+                                do {
+                                        ac = (ac << 3) + *arg++ - '0';
+                                        i++;
+                                } while (i < 4 && *arg >= '0' && *arg <= '7');
+                                *buffer++ = ac;
+                        } else if (*arg != '\0')
+                                *buffer++ = *arg++;
+                } else if (*arg == '[') {
+                        arg++;
+                        i = *arg++;
+                        if (*arg++ != '-') {
+                                *buffer++ = '[';
+                                arg -= 2;
+                                continue;
+                        }
+                        ac = *arg++;
+                        while (i <= ac)
+                                *buffer++ = i++;
+                        arg++;                          /* Skip ']' */
+                } else
+                        *buffer++ = *arg++;
         }
-        s->str += 2;
-        s->cnt = 0;
-        s->state = SET;
-        s->set = s->equiv;
 }
 
-static int genrange(s)
-STR *s;
+static void complement(unsigned char *buffer)
 {
-        int stopval;
-        char *savestart;
-
-        savestart = s->str;
-        stopval = *++s->str == '\\' ? backslash(s) : (u_char) * s->str++;
-        if (stopval < (u_char) s->lastch) {
-                s->str = savestart;
-                return (0);
+        register unsigned char *ptr;
+        register short i, index;
+        unsigned char conv[ASCII + 2];
+
+        index = 0;
+        for (i = 1; i <= ASCII; i++) {
+                for (ptr = buffer; *ptr; ptr++)
+                        if (*ptr == i)
+                                break;
+                if (*ptr == '\0')
+                        conv[index++] = i & ASCII;
         }
-        s->cnt = stopval - s->lastch + 1;
-        s->state = RANGE;
-        --s->lastch;
-        return (1);
+        conv[index] = '\0';
+        strcpy((char *) buffer, (char *) conv);
 }
 
-static void genseq(s)
-STR *s;
+extern int tr_main(int argc, char **argv)
 {
-        char *ep;
-
-        if (s->which == STRING1)
-                errx(1, "sequences only valid in string2");
-
-        if (*s->str == '\\')
-                s->lastch = backslash(s);
-        else
-                s->lastch = *s->str++;
-        if (*s->str != '*')
-                errx(1, "misplaced sequence asterisk");
-
-        switch (*++s->str) {
-        case '\\':
-                s->cnt = backslash(s);
-                break;
-        case ']':
-                s->cnt = 0;
-                ++s->str;
-                break;
-        default:
-                if (isdigit((u_char) * s->str)) {
-                        s->cnt = strtol(s->str, &ep, 0);
-                        if (*ep == ']') {
-                                s->str = ep + 1;
+        register unsigned char *ptr;
+        int index = 1;
+        short i;
+
+        if (argc > 1 && argv[index][0] == '-') {
+                for (ptr = (unsigned char *) &argv[index][1]; *ptr; ptr++) {
+                        switch (*ptr) {
+                        case 'c':
+                                com_fl = TRUE;
+                                break;
+                        case 'd':
+                                del_fl = TRUE;
                                 break;
+                        case 's':
+                                sq_fl = TRUE;
+                                break;
+                        default:
+                                usage("tr [-cds] STRING1 [STRING2]\n"
+#ifndef BB_FEATURE_TRIVIAL_HELP
+                                          "\nTranslate, squeeze, and/or delete characters from\n"
+                                          "standard input, writing to standard output.\n\n"
+                                          "Options:\n"
+                                          "\t-c\ttake complement of STRING1\n"
+                                          "\t-d\tdelete input characters coded STRING1\n"
+                                          "\t-s\tsqueeze multiple output characters of STRING2 into one character\n"
+#endif
+                                          );
                         }
                 }
-                errx(1, "illegal sequence count");
-                /* NOTREACHED */
+                index++;
+        }
+        for (i = 0; i <= ASCII; i++) {
+                vector[i] = i;
+                invec[i] = outvec[i] = FALSE;
         }
 
-        s->state = s->cnt ? SEQUENCE : INFINITE;
+        if (argv[index] != NULL) {
+                expand(argv[index++], input);
+                if (com_fl)
+                        complement(input);
+                if (argv[index] != NULL)
+                        expand(argv[index], output);
+                if (argv[index] != NULL)
+                        map(input, output);
+                for (ptr = input; *ptr; ptr++)
+                        invec[*ptr] = TRUE;
+                for (ptr = output; *ptr; ptr++)
+                        outvec[*ptr] = TRUE;
+        }
+        convert();
+        return (0);
 }
 
 /*
- * Translate \??? into a character.  Up to 3 octal digits, if no digits either
- * an escape code or a literal character.
+ * Copyright (c) 1987,1997, Prentice Hall
+ * All rights reserved.
+ * 
+ * Redistribution and use of the MINIX operating system in source and
+ * binary forms, with or without modification, are permitted provided
+ * that the following conditions are met:
+ * 
+ * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 
+ * 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.
+ * 
+ * Neither the name of Prentice Hall nor the names of the software
+ * authors or contributors may be used to endorse or promote
+ * products derived from this software without specific prior
+ * written permission.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS, AUTHORS, 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 PRENTICE HALL OR ANY AUTHORS 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.
+ *
  */
-static int backslash(s)
-register STR *s;
-{
-        register int ch, cnt, val;
 
-        for (cnt = val = 0;;) {
-                ch = (u_char) * ++s->str;
-                if (!isascii(ch) || !isdigit(ch))
-                        break;
-                val = val * 8 + ch - '0';
-                if (++cnt == 3) {
-                        ++s->str;
-                        break;
-                }
-        }
-        if (cnt)
-                return (val);
-        if (ch != '\0')
-                ++s->str;
-        switch (ch) {
-        case 'a':                                       /* escape characters */
-                return ('\7');
-        case 'b':
-                return ('\b');
-        case 'f':
-                return ('\f');
-        case 'n':
-                return ('\n');
-        case 'r':
-                return ('\r');
-        case 't':
-                return ('\t');
-        case 'v':
-                return ('\13');
-        case '\0':                                      /*  \" -> \ */
-                s->state = EOS;
-                return ('\\');
-        default:                                        /* \x" -> x */
-                return (ch);
-        }
-}