bin/sh/bltin/echo.c

   1 /*-
   2  * Copyright (c) 1991, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * This code is derived from software contributed to Berkeley by
   6  * Kenneth Almquist.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. Neither the name of the University nor the names of its contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  *
  32  *      @(#)echo.c      8.2 (Berkeley) 5/4/95
  33  */
  34
  35 #include <sys/cdefs.h>
  36 __FBSDID("$FreeBSD$");
  37
  38 /*
  39  * Echo command.
  40  */
  41
  42 #define main echocmd
  43
  44 #include "bltin.h"
  45
  46 /* #define eflag 1 */
  47
  48 int
  49 main(int argc, char *argv[])
  50 {
  51         char **ap;
  52         char *p;
  53         char c;
  54         int count;
  55         int nflag = 0;
  56 #ifndef eflag
  57         int eflag = 0;
  58 #endif
  59
  60         ap = argv;
  61         if (argc)
  62                 ap++;
  63         if ((p = *ap) != NULL) {
  64                 if (equal(p, "-n")) {
  65                         nflag++;
  66                         ap++;
  67                 } else if (equal(p, "-e")) {
  68 #ifndef eflag
  69                         eflag++;
  70 #endif
  71                         ap++;
  72                 }
  73         }
  74         while ((p = *ap++) != NULL) {
  75                 while ((c = *p++) != '\0') {
  76                         if (c == '\\' && eflag) {
  77                                 switch (*p++) {
  78                                 case 'a':  c = '\a';  break;
  79                                 case 'b':  c = '\b';  break;
  80                                 case 'c':  return 0;            /* exit */
  81                                 case 'e':  c = '\033';  break;
  82                                 case 'f':  c = '\f';  break;
  83                                 case 'n':  c = '\n';  break;
  84                                 case 'r':  c = '\r';  break;
  85                                 case 't':  c = '\t';  break;
  86                                 case 'v':  c = '\v';  break;
  87                                 case '\\':  break;              /* c = '\\' */
  88                                 case '0':
  89                                         c = 0;
  90                                         count = 3;
  91                                         while (--count >= 0 && (unsigned)(*p - '0') < 8)
  92                                                 c = (c << 3) + (*p++ - '0');
  93                                         break;
  94                                 default:
  95                                         p--;
  96                                         break;
  97                                 }
  98                         }
  99                         putchar(c);
 100                 }
 101                 if (*ap)
 102                         putchar(' ');
 103         }
 104         if (! nflag)
 105                 putchar('\n');
 106         return 0;
 107 }