Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 1 | /* vi: set sw=4 ts=4: */ |
Erik Andersen | 13456d1 | 2000-03-16 08:09:57 +0000 | [diff] [blame] | 2 | /* |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 3 | * echo implementation for busybox |
Erik Andersen | 13456d1 | 2000-03-16 08:09:57 +0000 | [diff] [blame] | 4 | * |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 5 | * Copyright (c) 1991, 1993 |
| 6 | * The Regents of the University of California. All rights reserved. |
Erik Andersen | 13456d1 | 2000-03-16 08:09:57 +0000 | [diff] [blame] | 7 | * |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 8 | * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. |
Erik Andersen | 13456d1 | 2000-03-16 08:09:57 +0000 | [diff] [blame] | 9 | * |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 10 | * Original copyright notice is retained at the end of this file. |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 11 | */ |
| 12 | |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 13 | /* BB_AUDIT SUSv3 compliant -- unless configured as fancy echo. */ |
| 14 | /* http://www.opengroup.org/onlinepubs/007904975/utilities/echo.html */ |
| 15 | |
| 16 | /* Mar 16, 2003 Manuel Novoa III (mjn3@codepoet.org) |
| 17 | * |
| 18 | * Because of behavioral differences, implemented configurable SUSv3 |
| 19 | * or 'fancy' gnu-ish behaviors. Also, reduced size and fixed bugs. |
| 20 | * 1) In handling '\c' escape, the previous version only suppressed the |
| 21 | * trailing newline. SUSv3 specifies _no_ output after '\c'. |
| 22 | * 2) SUSv3 specifies that octal escapes are of the form \0{#{#{#}}}. |
Denis Vlasenko | 7e754f1 | 2007-04-09 13:04:50 +0000 | [diff] [blame] | 23 | * The previous version did not allow 4-digit octals. |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 24 | */ |
| 25 | |
Denis Vlasenko | b6adbf1 | 2007-05-26 19:00:18 +0000 | [diff] [blame] | 26 | #include "libbb.h" |
Erik Andersen | 13456d1 | 2000-03-16 08:09:57 +0000 | [diff] [blame] | 27 | |
Denis Vlasenko | fe5e23b | 2007-11-24 02:23:51 +0000 | [diff] [blame] | 28 | /* This is a NOFORK applet. Be very careful! */ |
| 29 | |
Denis Vlasenko | 7d75a96 | 2007-11-22 08:16:57 +0000 | [diff] [blame] | 30 | /* argc is unused, but removing it precludes compiler from |
| 31 | * using call -> jump optimization */ |
Denis Vlasenko | fe5e23b | 2007-11-24 02:23:51 +0000 | [diff] [blame] | 32 | |
| 33 | int echo_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
Denis Vlasenko | 68404f1 | 2008-03-17 09:00:54 +0000 | [diff] [blame] | 34 | int echo_main(int argc ATTRIBUTE_UNUSED, char **argv) |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 35 | { |
Denis Vlasenko | 7e754f1 | 2007-04-09 13:04:50 +0000 | [diff] [blame] | 36 | const char *arg; |
| 37 | #if !ENABLE_FEATURE_FANCY_ECHO |
Denis Vlasenko | a9d7d24 | 2007-04-10 16:34:00 +0000 | [diff] [blame] | 38 | enum { |
| 39 | eflag = '\\', |
| 40 | nflag = 1, /* 1 -- print '\n' */ |
| 41 | }; |
Denis Vlasenko | 7d75a96 | 2007-11-22 08:16:57 +0000 | [diff] [blame] | 42 | |
| 43 | /* We must check that stdout is not closed. |
| 44 | * The reason for this is highly non-obvious. |
Denis Vlasenko | fe5e23b | 2007-11-24 02:23:51 +0000 | [diff] [blame] | 45 | * echo_main is used from shell. Shell must correctly handle "echo foo" |
Denis Vlasenko | 7d75a96 | 2007-11-22 08:16:57 +0000 | [diff] [blame] | 46 | * if stdout is closed. With stdio, output gets shoveled into |
| 47 | * stdout buffer, and even fflush cannot clear it out. It seems that |
| 48 | * even if libc receives EBADF on write attempts, it feels determined |
| 49 | * to output data no matter what. So it will try later, |
| 50 | * and possibly will clobber future output. Not good. */ |
| 51 | if (dup2(1, 1) != 1) |
| 52 | return -1; |
| 53 | |
Denis Vlasenko | bb98db2 | 2007-06-19 23:04:17 +0000 | [diff] [blame] | 54 | arg = *++argv; |
Bernhard Reutner-Fischer | def8260 | 2007-06-08 12:52:17 +0000 | [diff] [blame] | 55 | if (!arg) |
| 56 | goto newline_ret; |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 57 | #else |
| 58 | const char *p; |
Denis Vlasenko | 7e754f1 | 2007-04-09 13:04:50 +0000 | [diff] [blame] | 59 | char nflag = 1; |
| 60 | char eflag = 0; |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 61 | |
Denis Vlasenko | 7d75a96 | 2007-11-22 08:16:57 +0000 | [diff] [blame] | 62 | /* We must check that stdout is not closed. */ |
| 63 | if (dup2(1, 1) != 1) |
| 64 | return -1; |
| 65 | |
Denis Vlasenko | 7e754f1 | 2007-04-09 13:04:50 +0000 | [diff] [blame] | 66 | while (1) { |
| 67 | arg = *++argv; |
| 68 | if (!arg) |
Denis Vlasenko | a9d7d24 | 2007-04-10 16:34:00 +0000 | [diff] [blame] | 69 | goto newline_ret; |
Denis Vlasenko | 7e754f1 | 2007-04-09 13:04:50 +0000 | [diff] [blame] | 70 | if (*arg != '-') |
| 71 | break; |
| 72 | |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 73 | /* If it appears that we are handling options, then make sure |
| 74 | * that all of the options specified are actually valid. |
| 75 | * Otherwise, the string should just be echoed. |
| 76 | */ |
Denis Vlasenko | 7e754f1 | 2007-04-09 13:04:50 +0000 | [diff] [blame] | 77 | p = arg + 1; |
| 78 | if (!*p) /* A single '-', so echo it. */ |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 79 | goto just_echo; |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 80 | |
| 81 | do { |
Denis Vlasenko | 7e754f1 | 2007-04-09 13:04:50 +0000 | [diff] [blame] | 82 | if (!strrchr("neE", *p)) |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 83 | goto just_echo; |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 84 | } while (*++p); |
| 85 | |
| 86 | /* All of the options in this arg are valid, so handle them. */ |
Denis Vlasenko | 7e754f1 | 2007-04-09 13:04:50 +0000 | [diff] [blame] | 87 | p = arg + 1; |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 88 | do { |
Denis Vlasenko | 7e754f1 | 2007-04-09 13:04:50 +0000 | [diff] [blame] | 89 | if (*p == 'n') |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 90 | nflag = 0; |
Denis Vlasenko | 7e754f1 | 2007-04-09 13:04:50 +0000 | [diff] [blame] | 91 | if (*p == 'e') |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 92 | eflag = '\\'; |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 93 | } while (*++p); |
| 94 | } |
Denis Vlasenko | 7e754f1 | 2007-04-09 13:04:50 +0000 | [diff] [blame] | 95 | just_echo: |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 96 | #endif |
Denis Vlasenko | 7e754f1 | 2007-04-09 13:04:50 +0000 | [diff] [blame] | 97 | while (1) { |
Denis Vlasenko | a9d7d24 | 2007-04-10 16:34:00 +0000 | [diff] [blame] | 98 | /* arg is already == *argv and isn't NULL */ |
"Robert P. J. Day" | 6822983 | 2006-07-01 13:08:46 +0000 | [diff] [blame] | 99 | int c; |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 100 | |
Denis Vlasenko | a9d7d24 | 2007-04-10 16:34:00 +0000 | [diff] [blame] | 101 | if (!eflag) { |
| 102 | /* optimization for very common case */ |
| 103 | fputs(arg, stdout); |
| 104 | } else while ((c = *arg++)) { |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 105 | if (c == eflag) { /* Check for escape seq. */ |
Denis Vlasenko | 7e754f1 | 2007-04-09 13:04:50 +0000 | [diff] [blame] | 106 | if (*arg == 'c') { |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 107 | /* '\c' means cancel newline and |
| 108 | * ignore all subsequent chars. */ |
Denis Vlasenko | 7e754f1 | 2007-04-09 13:04:50 +0000 | [diff] [blame] | 109 | goto ret; |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 110 | } |
Denis Vlasenko | 7e754f1 | 2007-04-09 13:04:50 +0000 | [diff] [blame] | 111 | #if !ENABLE_FEATURE_FANCY_ECHO |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 112 | /* SUSv3 specifies that octal escapes must begin with '0'. */ |
Denis Vlasenko | 7e754f1 | 2007-04-09 13:04:50 +0000 | [diff] [blame] | 113 | if ( (((unsigned char)*arg) - '1') >= 7) |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 114 | #endif |
| 115 | { |
| 116 | /* Since SUSv3 mandates a first digit of 0, 4-digit octals |
| 117 | * of the form \0### are accepted. */ |
Denis Vlasenko | 7e754f1 | 2007-04-09 13:04:50 +0000 | [diff] [blame] | 118 | if (*arg == '0' && ((unsigned char)(arg[1]) - '0') < 8) { |
| 119 | arg++; |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 120 | } |
| 121 | /* bb_process_escape_sequence can handle nul correctly */ |
Denis Vlasenko | 7e754f1 | 2007-04-09 13:04:50 +0000 | [diff] [blame] | 122 | c = bb_process_escape_sequence(&arg); |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 123 | } |
| 124 | } |
Denis Vlasenko | 4daad90 | 2007-09-27 10:20:47 +0000 | [diff] [blame] | 125 | bb_putchar(c); |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 126 | } |
| 127 | |
Denis Vlasenko | 7e754f1 | 2007-04-09 13:04:50 +0000 | [diff] [blame] | 128 | arg = *++argv; |
| 129 | if (!arg) |
| 130 | break; |
Denis Vlasenko | 4daad90 | 2007-09-27 10:20:47 +0000 | [diff] [blame] | 131 | bb_putchar(' '); |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 132 | } |
| 133 | |
Denis Vlasenko | a9d7d24 | 2007-04-10 16:34:00 +0000 | [diff] [blame] | 134 | newline_ret: |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 135 | if (nflag) { |
Denis Vlasenko | 4daad90 | 2007-09-27 10:20:47 +0000 | [diff] [blame] | 136 | bb_putchar('\n'); |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 137 | } |
Denis Vlasenko | 7e754f1 | 2007-04-09 13:04:50 +0000 | [diff] [blame] | 138 | ret: |
| 139 | return fflush(stdout); |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 140 | } |
| 141 | |
Paul Fox | 6ab0378 | 2006-06-08 21:37:26 +0000 | [diff] [blame] | 142 | /*- |
| 143 | * Copyright (c) 1991, 1993 |
| 144 | * The Regents of the University of California. All rights reserved. |
| 145 | * |
| 146 | * This code is derived from software contributed to Berkeley by |
| 147 | * Kenneth Almquist. |
| 148 | * |
| 149 | * Redistribution and use in source and binary forms, with or without |
| 150 | * modification, are permitted provided that the following conditions |
| 151 | * are met: |
| 152 | * 1. Redistributions of source code must retain the above copyright |
| 153 | * notice, this list of conditions and the following disclaimer. |
| 154 | * 2. Redistributions in binary form must reproduce the above copyright |
| 155 | * notice, this list of conditions and the following disclaimer in the |
| 156 | * documentation and/or other materials provided with the distribution. |
| 157 | * |
| 158 | * 3. <BSD Advertising Clause omitted per the July 22, 1999 licensing change |
| 159 | * ftp://ftp.cs.berkeley.edu/pub/4bsd/README.Impt.License.Change> |
| 160 | * |
| 161 | * California, Berkeley and its contributors. |
| 162 | * 4. Neither the name of the University nor the names of its contributors |
| 163 | * may be used to endorse or promote products derived from this software |
| 164 | * without specific prior written permission. |
| 165 | * |
| 166 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 167 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 168 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 169 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 170 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 171 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 172 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 173 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 174 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 175 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 176 | * SUCH DAMAGE. |
| 177 | * |
| 178 | * @(#)echo.c 8.1 (Berkeley) 5/31/93 |
| 179 | */ |
Denis Vlasenko | 7d75a96 | 2007-11-22 08:16:57 +0000 | [diff] [blame] | 180 | |
| 181 | #ifdef VERSION_WITH_WRITEV |
| 182 | /* We can't use stdio. |
| 183 | * The reason for this is highly non-obvious. |
Denis Vlasenko | fe5e23b | 2007-11-24 02:23:51 +0000 | [diff] [blame] | 184 | * echo_main is used from shell. Shell must correctly handle "echo foo" |
Denis Vlasenko | 7d75a96 | 2007-11-22 08:16:57 +0000 | [diff] [blame] | 185 | * if stdout is closed. With stdio, output gets shoveled into |
| 186 | * stdout buffer, and even fflush cannot clear it out. It seems that |
| 187 | * even if libc receives EBADF on write attempts, it feels determined |
| 188 | * to output data no matter what. So it will try later, |
| 189 | * and possibly will clobber future output. Not good. |
| 190 | * |
| 191 | * Using writev instead, with 'direct' conversion of argv vector. |
| 192 | */ |
| 193 | |
Denis Vlasenko | fe5e23b | 2007-11-24 02:23:51 +0000 | [diff] [blame] | 194 | int echo_main(int argc, char **argv) |
Denis Vlasenko | 7d75a96 | 2007-11-22 08:16:57 +0000 | [diff] [blame] | 195 | { |
| 196 | struct iovec io[argc]; |
| 197 | struct iovec *cur_io = io; |
| 198 | char *arg; |
| 199 | char *p; |
| 200 | #if !ENABLE_FEATURE_FANCY_ECHO |
| 201 | enum { |
| 202 | eflag = '\\', |
| 203 | nflag = 1, /* 1 -- print '\n' */ |
| 204 | }; |
| 205 | arg = *++argv; |
| 206 | if (!arg) |
| 207 | goto newline_ret; |
| 208 | #else |
| 209 | char nflag = 1; |
| 210 | char eflag = 0; |
| 211 | |
| 212 | while (1) { |
| 213 | arg = *++argv; |
| 214 | if (!arg) |
| 215 | goto newline_ret; |
| 216 | if (*arg != '-') |
| 217 | break; |
| 218 | |
| 219 | /* If it appears that we are handling options, then make sure |
| 220 | * that all of the options specified are actually valid. |
| 221 | * Otherwise, the string should just be echoed. |
| 222 | */ |
| 223 | p = arg + 1; |
| 224 | if (!*p) /* A single '-', so echo it. */ |
| 225 | goto just_echo; |
| 226 | |
| 227 | do { |
| 228 | if (!strrchr("neE", *p)) |
| 229 | goto just_echo; |
| 230 | } while (*++p); |
| 231 | |
| 232 | /* All of the options in this arg are valid, so handle them. */ |
| 233 | p = arg + 1; |
| 234 | do { |
| 235 | if (*p == 'n') |
| 236 | nflag = 0; |
| 237 | if (*p == 'e') |
| 238 | eflag = '\\'; |
| 239 | } while (*++p); |
| 240 | } |
| 241 | just_echo: |
| 242 | #endif |
| 243 | |
| 244 | while (1) { |
| 245 | /* arg is already == *argv and isn't NULL */ |
| 246 | int c; |
| 247 | |
| 248 | cur_io->iov_base = p = arg; |
| 249 | |
| 250 | if (!eflag) { |
| 251 | /* optimization for very common case */ |
| 252 | p += strlen(arg); |
| 253 | } else while ((c = *arg++)) { |
| 254 | if (c == eflag) { /* Check for escape seq. */ |
| 255 | if (*arg == 'c') { |
| 256 | /* '\c' means cancel newline and |
| 257 | * ignore all subsequent chars. */ |
| 258 | cur_io->iov_len = p - (char*)cur_io->iov_base; |
| 259 | cur_io++; |
| 260 | goto ret; |
| 261 | } |
| 262 | #if !ENABLE_FEATURE_FANCY_ECHO |
| 263 | /* SUSv3 specifies that octal escapes must begin with '0'. */ |
| 264 | if ( (((unsigned char)*arg) - '1') >= 7) |
| 265 | #endif |
| 266 | { |
| 267 | /* Since SUSv3 mandates a first digit of 0, 4-digit octals |
| 268 | * of the form \0### are accepted. */ |
| 269 | if (*arg == '0' && ((unsigned char)(arg[1]) - '0') < 8) { |
| 270 | arg++; |
| 271 | } |
| 272 | /* bb_process_escape_sequence can handle nul correctly */ |
| 273 | c = bb_process_escape_sequence( (void*) &arg); |
| 274 | } |
| 275 | } |
| 276 | *p++ = c; |
| 277 | } |
| 278 | |
| 279 | arg = *++argv; |
| 280 | if (arg) |
| 281 | *p++ = ' '; |
| 282 | cur_io->iov_len = p - (char*)cur_io->iov_base; |
| 283 | cur_io++; |
| 284 | if (!arg) |
| 285 | break; |
| 286 | } |
| 287 | |
| 288 | newline_ret: |
| 289 | if (nflag) { |
| 290 | cur_io->iov_base = (char*)"\n"; |
| 291 | cur_io->iov_len = 1; |
| 292 | cur_io++; |
| 293 | } |
| 294 | ret: |
| 295 | /* TODO: implement and use full_writev? */ |
Denis Vlasenko | f7be20e | 2007-12-24 14:09:19 +0000 | [diff] [blame] | 296 | return writev(1, io, (cur_io - io)) >= 0; |
Denis Vlasenko | 7d75a96 | 2007-11-22 08:16:57 +0000 | [diff] [blame] | 297 | } |
| 298 | #endif |