| The Android Open Source Project | dd7bc33 | 2009-03-03 19:32:55 -0800 | [diff] [blame] | 1 | /* $NetBSD: echo.c,v 1.12 2005/02/06 04:43:43 perry Exp $ */ |
| 2 | |
| 3 | /*- |
| 4 | * Copyright (c) 1991, 1993 |
| 5 | * The Regents of the University of California. All rights reserved. |
| 6 | * |
| 7 | * This code is derived from software contributed to Berkeley by |
| 8 | * Kenneth Almquist. |
| 9 | * |
| 10 | * Redistribution and use in source and binary forms, with or without |
| 11 | * modification, are permitted provided that the following conditions |
| 12 | * are met: |
| 13 | * 1. Redistributions of source code must retain the above copyright |
| 14 | * notice, this list of conditions and the following disclaimer. |
| 15 | * 2. Redistributions in binary form must reproduce the above copyright |
| 16 | * notice, this list of conditions and the following disclaimer in the |
| 17 | * documentation and/or other materials provided with the distribution. |
| 18 | * 3. Neither the name of the University nor the names of its contributors |
| 19 | * may be used to endorse or promote products derived from this software |
| 20 | * without specific prior written permission. |
| 21 | * |
| 22 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 23 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 24 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 25 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 26 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 27 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 28 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 29 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 30 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 31 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 32 | * SUCH DAMAGE. |
| 33 | * |
| 34 | * @(#)echo.c 8.1 (Berkeley) 5/31/93 |
| 35 | */ |
| 36 | |
| 37 | /* |
| 38 | * Echo command. |
| 39 | * |
| 40 | * echo is steeped in tradition - several of them! |
| 41 | * netbsd has supported 'echo [-n | -e] args' in spite of -e not being |
| 42 | * documented anywhere. |
| 43 | * Posix requires that -n be supported, output from strings containing |
| 44 | * \ is implementation defined |
| 45 | * The Single Unix Spec requires that \ escapes be treated as if -e |
| 46 | * were set, but that -n not be treated as an option. |
| 47 | * (ksh supports 'echo [-eEn] args', but not -- so that it is actually |
| 48 | * impossible to actually output '-n') |
| 49 | * |
| 50 | * It is suggested that 'printf "%b" "string"' be used to get \ sequences |
| 51 | * expanded. printf is now a builtin of netbsd's sh and csh. |
| 52 | */ |
| 53 | |
| 54 | //#define main echocmd |
| 55 | |
| 56 | #include "bltin.h" |
| 57 | |
| 58 | int |
| 59 | echocmd(int argc, char **argv) |
| 60 | { |
| 61 | char **ap; |
| 62 | char *p; |
| 63 | char c; |
| 64 | int count; |
| 65 | int nflag = 0; |
| 66 | int eflag = 0; |
| 67 | |
| 68 | ap = argv; |
| 69 | if (argc) |
| 70 | ap++; |
| 71 | |
| 72 | if ((p = *ap) != NULL) { |
| 73 | if (equal(p, "-n")) { |
| 74 | nflag = 1; |
| 75 | ap++; |
| 76 | } else if (equal(p, "-e")) { |
| 77 | eflag = 1; |
| 78 | ap++; |
| 79 | } |
| 80 | } |
| 81 | |
| 82 | while ((p = *ap++) != NULL) { |
| 83 | while ((c = *p++) != '\0') { |
| 84 | if (c == '\\' && eflag) { |
| 85 | switch (*p++) { |
| 86 | case 'a': c = '\a'; break; /* bell */ |
| 87 | case 'b': c = '\b'; break; |
| 88 | case 'c': return 0; /* exit */ |
| 89 | case 'e': c = 033; break; /* escape */ |
| 90 | case 'f': c = '\f'; break; |
| 91 | case 'n': c = '\n'; break; |
| 92 | case 'r': c = '\r'; break; |
| 93 | case 't': c = '\t'; break; |
| 94 | case 'v': c = '\v'; break; |
| 95 | case '\\': break; /* c = '\\' */ |
| 96 | case '0': |
| 97 | c = 0; |
| 98 | count = 3; |
| 99 | while (--count >= 0 && (unsigned)(*p - '0') < 8) |
| 100 | c = (c << 3) + (*p++ - '0'); |
| 101 | break; |
| 102 | default: |
| 103 | /* Output the '/' and char following */ |
| 104 | p--; |
| 105 | break; |
| 106 | } |
| 107 | } |
| 108 | putchar(c); |
| 109 | } |
| 110 | if (*ap) |
| 111 | putchar(' '); |
| 112 | } |
| 113 | if (! nflag) |
| 114 | putchar('\n'); |
| 115 | return 0; |
| 116 | } |