| 1 | # |
| 2 | # For a description of the syntax of this configuration file, |
| 3 | # see scripts/kbuild/config-language.txt. |
| 4 | # |
| 5 | |
| 6 | menu "Shells" |
| 7 | |
| 8 | config BUSYBOX_CONFIG_ASH |
| 9 | bool "ash" |
| 10 | default y |
| 11 | depends on !BUSYBOX_CONFIG_NOMMU |
| 12 | help |
| 13 | Tha 'ash' shell adds about 60k in the default configuration and is |
| 14 | the most complete and most pedantically correct shell included with |
| 15 | busybox. This shell is actually a derivative of the Debian 'dash' |
| 16 | shell (by Herbert Xu), which was created by porting the 'ash' shell |
| 17 | (written by Kenneth Almquist) from NetBSD. |
| 18 | |
| 19 | config BUSYBOX_CONFIG_ASH_BASH_COMPAT |
| 20 | bool "bash-compatible extensions" |
| 21 | default y |
| 22 | depends on BUSYBOX_CONFIG_ASH |
| 23 | help |
| 24 | Enable bash-compatible extensions. |
| 25 | |
| 26 | config BUSYBOX_CONFIG_ASH_JOB_CONTROL |
| 27 | bool "Job control" |
| 28 | default y |
| 29 | depends on BUSYBOX_CONFIG_ASH |
| 30 | help |
| 31 | Enable job control in the ash shell. |
| 32 | |
| 33 | config BUSYBOX_CONFIG_ASH_ALIAS |
| 34 | bool "alias support" |
| 35 | default y |
| 36 | depends on BUSYBOX_CONFIG_ASH |
| 37 | help |
| 38 | Enable alias support in the ash shell. |
| 39 | |
| 40 | config BUSYBOX_CONFIG_ASH_GETOPTS |
| 41 | bool "Builtin getopt to parse positional parameters" |
| 42 | default y |
| 43 | depends on BUSYBOX_CONFIG_ASH |
| 44 | help |
| 45 | Enable getopts builtin in the ash shell. |
| 46 | |
| 47 | config BUSYBOX_CONFIG_ASH_BUILTIN_ECHO |
| 48 | bool "Builtin version of 'echo'" |
| 49 | default y |
| 50 | depends on BUSYBOX_CONFIG_ASH |
| 51 | help |
| 52 | Enable support for echo, builtin to ash. |
| 53 | |
| 54 | config BUSYBOX_CONFIG_ASH_BUILTIN_PRINTF |
| 55 | bool "Builtin version of 'printf'" |
| 56 | default y |
| 57 | depends on BUSYBOX_CONFIG_ASH |
| 58 | help |
| 59 | Enable support for printf, builtin to ash. |
| 60 | |
| 61 | config BUSYBOX_CONFIG_ASH_BUILTIN_TEST |
| 62 | bool "Builtin version of 'test'" |
| 63 | default y |
| 64 | depends on BUSYBOX_CONFIG_ASH |
| 65 | help |
| 66 | Enable support for test, builtin to ash. |
| 67 | |
| 68 | config BUSYBOX_CONFIG_ASH_CMDCMD |
| 69 | bool "'command' command to override shell builtins" |
| 70 | default y |
| 71 | depends on BUSYBOX_CONFIG_ASH |
| 72 | help |
| 73 | Enable support for the ash 'command' builtin, which allows |
| 74 | you to run the specified command with the specified arguments, |
| 75 | even when there is an ash builtin command with the same name. |
| 76 | |
| 77 | config BUSYBOX_CONFIG_ASH_MAIL |
| 78 | bool "Check for new mail on interactive shells" |
| 79 | default n |
| 80 | depends on BUSYBOX_CONFIG_ASH |
| 81 | help |
| 82 | Enable "check for new mail" in the ash shell. |
| 83 | |
| 84 | config BUSYBOX_CONFIG_ASH_OPTIMIZE_FOR_SIZE |
| 85 | bool "Optimize for size instead of speed" |
| 86 | default n |
| 87 | depends on BUSYBOX_CONFIG_ASH |
| 88 | help |
| 89 | Compile ash for reduced size at the price of speed. |
| 90 | |
| 91 | config BUSYBOX_CONFIG_ASH_RANDOM_SUPPORT |
| 92 | bool "Pseudorandom generator and $RANDOM variable" |
| 93 | default n |
| 94 | depends on BUSYBOX_CONFIG_ASH |
| 95 | help |
| 96 | Enable pseudorandom generator and dynamic variable "$RANDOM". |
| 97 | Each read of "$RANDOM" will generate a new pseudorandom value. |
| 98 | You can reset the generator by using a specified start value. |
| 99 | After "unset RANDOM" the generator will switch off and this |
| 100 | variable will no longer have special treatment. |
| 101 | |
| 102 | config BUSYBOX_CONFIG_ASH_EXPAND_PRMT |
| 103 | bool "Expand prompt string" |
| 104 | default y |
| 105 | depends on BUSYBOX_CONFIG_ASH |
| 106 | help |
| 107 | "PS#" may contain volatile content, such as backquote commands. |
| 108 | This option recreates the prompt string from the environment |
| 109 | variable each time it is displayed. |
| 110 | |
| 111 | config BUSYBOX_CONFIG_CTTYHACK |
| 112 | bool "cttyhack" |
| 113 | default n |
| 114 | help |
| 115 | One common problem reported on the mailing list is "can't access tty; |
| 116 | job control turned off" error message which typically appears when |
| 117 | one tries to use shell with stdin/stdout opened to /dev/console. |
| 118 | This device is special - it cannot be a controlling tty. |
| 119 | |
| 120 | Proper solution is to use correct device instead of /dev/console. |
| 121 | |
| 122 | cttyhack provides "quick and dirty" solution to this problem. |
| 123 | It analyzes stdin with various ioctls, trying to determine whether |
| 124 | it is a /dev/ttyN or /dev/ttySN (virtual terminal or serial line). |
| 125 | If it detects one, it closes stdin/out/err and reopens that device. |
| 126 | Then it executes given program. Opening the device will make |
| 127 | that device a controlling tty. This may require cttyhack |
| 128 | to be a session leader. |
| 129 | |
| 130 | Example for /etc/inittab (for busybox init): |
| 131 | |
| 132 | ::respawn:/bin/cttyhack /bin/sh |
| 133 | |
| 134 | Starting an interactive shell from boot shell script: |
| 135 | |
| 136 | setsid cttyhack sh |
| 137 | |
| 138 | Giving controlling tty to shell running with PID 1: |
| 139 | |
| 140 | # exec cttyhack sh |
| 141 | |
| 142 | Without cttyhack, you need to know exact tty name, |
| 143 | and do something like this: |
| 144 | |
| 145 | # exec setsid sh -c 'exec sh </dev/tty1 >/dev/tty1 2>&1' |
| 146 | |
| 147 | config BUSYBOX_CONFIG_HUSH |
| 148 | bool "hush" |
| 149 | default n |
| 150 | help |
| 151 | hush is a small shell (25k). It handles the normal flow control |
| 152 | constructs such as if/then/elif/else/fi, for/in/do/done, while loops, |
| 153 | case/esac. Redirections, here documents, $((arithmetic)) |
| 154 | and functions are supported. |
| 155 | |
| 156 | It will compile and work on no-mmu systems. |
| 157 | |
| 158 | It does not handle select, aliases, tilde expansion, |
| 159 | &>file and >&file redirection of stdout+stderr. |
| 160 | |
| 161 | config BUSYBOX_CONFIG_HUSH_BASH_COMPAT |
| 162 | bool "bash-compatible extensions" |
| 163 | default y |
| 164 | depends on BUSYBOX_CONFIG_HUSH |
| 165 | help |
| 166 | Enable bash-compatible extensions. |
| 167 | |
| 168 | config BUSYBOX_CONFIG_HUSH_BRACE_EXPANSION |
| 169 | bool "Brace expansion" |
| 170 | default n |
| 171 | depends on BUSYBOX_CONFIG_HUSH_BASH_COMPAT |
| 172 | help |
| 173 | Enable {abc,def} extension. |
| 174 | |
| 175 | config BUSYBOX_CONFIG_HUSH_HELP |
| 176 | bool "help builtin" |
| 177 | default y |
| 178 | depends on BUSYBOX_CONFIG_HUSH |
| 179 | help |
| 180 | Enable help builtin in hush. Code size + ~1 kbyte. |
| 181 | |
| 182 | config BUSYBOX_CONFIG_HUSH_INTERACTIVE |
| 183 | bool "Interactive mode" |
| 184 | default y |
| 185 | depends on BUSYBOX_CONFIG_HUSH |
| 186 | help |
| 187 | Enable interactive mode (prompt and command editing). |
| 188 | Without this, hush simply reads and executes commands |
| 189 | from stdin just like a shell script from a file. |
| 190 | No prompt, no PS1/PS2 magic shell variables. |
| 191 | |
| 192 | config BUSYBOX_CONFIG_HUSH_SAVEHISTORY |
| 193 | bool "Save command history to .hush_history" |
| 194 | default n |
| 195 | depends on BUSYBOX_CONFIG_HUSH_INTERACTIVE && BUSYBOX_CONFIG_FEATURE_EDITING_SAVEHISTORY |
| 196 | help |
| 197 | Enable history saving in hush. |
| 198 | |
| 199 | config BUSYBOX_CONFIG_HUSH_JOB |
| 200 | bool "Job control" |
| 201 | default y |
| 202 | depends on BUSYBOX_CONFIG_HUSH_INTERACTIVE |
| 203 | help |
| 204 | Enable job control: Ctrl-Z backgrounds, Ctrl-C interrupts current |
| 205 | command (not entire shell), fg/bg builtins work. Without this option, |
| 206 | "cmd &" still works by simply spawning a process and immediately |
| 207 | prompting for next command (or executing next command in a script), |
| 208 | but no separate process group is formed. |
| 209 | |
| 210 | config BUSYBOX_CONFIG_HUSH_TICK |
| 211 | bool "Process substitution" |
| 212 | default y |
| 213 | depends on BUSYBOX_CONFIG_HUSH |
| 214 | help |
| 215 | Enable process substitution `command` and $(command) in hush. |
| 216 | |
| 217 | config BUSYBOX_CONFIG_HUSH_IF |
| 218 | bool "Support if/then/elif/else/fi" |
| 219 | default y |
| 220 | depends on BUSYBOX_CONFIG_HUSH |
| 221 | help |
| 222 | Enable if/then/elif/else/fi in hush. |
| 223 | |
| 224 | config BUSYBOX_CONFIG_HUSH_LOOPS |
| 225 | bool "Support for, while and until loops" |
| 226 | default y |
| 227 | depends on BUSYBOX_CONFIG_HUSH |
| 228 | help |
| 229 | Enable for, while and until loops in hush. |
| 230 | |
| 231 | config BUSYBOX_CONFIG_HUSH_CASE |
| 232 | bool "Support case ... esac statement" |
| 233 | default y |
| 234 | depends on BUSYBOX_CONFIG_HUSH |
| 235 | help |
| 236 | Enable case ... esac statement in hush. +400 bytes. |
| 237 | |
| 238 | config BUSYBOX_CONFIG_HUSH_FUNCTIONS |
| 239 | bool "Support funcname() { commands; } syntax" |
| 240 | default y |
| 241 | depends on BUSYBOX_CONFIG_HUSH |
| 242 | help |
| 243 | Enable support for shell functions in hush. +800 bytes. |
| 244 | |
| 245 | config BUSYBOX_CONFIG_HUSH_LOCAL |
| 246 | bool "Support local builtin" |
| 247 | default y |
| 248 | depends on BUSYBOX_CONFIG_HUSH_FUNCTIONS |
| 249 | help |
| 250 | Enable support for local variables in functions. |
| 251 | |
| 252 | config BUSYBOX_CONFIG_HUSH_RANDOM_SUPPORT |
| 253 | bool "Pseudorandom generator and $RANDOM variable" |
| 254 | default n |
| 255 | depends on BUSYBOX_CONFIG_HUSH |
| 256 | help |
| 257 | Enable pseudorandom generator and dynamic variable "$RANDOM". |
| 258 | Each read of "$RANDOM" will generate a new pseudorandom value. |
| 259 | |
| 260 | config BUSYBOX_CONFIG_HUSH_EXPORT_N |
| 261 | bool "Support 'export -n' option" |
| 262 | default y |
| 263 | depends on BUSYBOX_CONFIG_HUSH |
| 264 | help |
| 265 | export -n unexports variables. It is a bash extension. |
| 266 | |
| 267 | config BUSYBOX_CONFIG_HUSH_MODE_X |
| 268 | bool "Support 'hush -x' option and 'set -x' command" |
| 269 | default n |
| 270 | depends on BUSYBOX_CONFIG_HUSH |
| 271 | help |
| 272 | This instructs hush to print commands before execution. |
| 273 | Adds ~300 bytes. |
| 274 | |
| 275 | config BUSYBOX_CONFIG_MSH |
| 276 | bool "msh (deprecated: aliased to hush)" |
| 277 | default n |
| 278 | select BUSYBOX_CONFIG_HUSH |
| 279 | help |
| 280 | msh is deprecated and will be removed, please migrate to hush. |
| 281 | |
| 282 | |
| 283 | choice |
| 284 | prompt "Choose which shell is aliased to 'sh' name" |
| 285 | default BUSYBOX_CONFIG_FEATURE_SH_IS_ASH |
| 286 | help |
| 287 | Choose which shell you want to be executed by 'sh' alias. |
| 288 | The ash shell is the most bash compatible and full featured one. |
| 289 | |
| 290 | # note: cannot use "select ASH" here, it breaks "make allnoconfig" |
| 291 | config BUSYBOX_CONFIG_FEATURE_SH_IS_ASH |
| 292 | depends on BUSYBOX_CONFIG_ASH |
| 293 | bool "ash" |
| 294 | depends on !BUSYBOX_CONFIG_NOMMU |
| 295 | |
| 296 | config BUSYBOX_CONFIG_FEATURE_SH_IS_HUSH |
| 297 | depends on BUSYBOX_CONFIG_HUSH |
| 298 | bool "hush" |
| 299 | |
| 300 | config BUSYBOX_CONFIG_FEATURE_SH_IS_NONE |
| 301 | bool "none" |
| 302 | |
| 303 | endchoice |
| 304 | |
| 305 | choice |
| 306 | prompt "Choose which shell is aliased to 'bash' name" |
| 307 | default BUSYBOX_CONFIG_FEATURE_BASH_IS_NONE |
| 308 | help |
| 309 | Choose which shell you want to be executed by 'bash' alias. |
| 310 | The ash shell is the most bash compatible and full featured one. |
| 311 | |
| 312 | Note that selecting this option does not switch on any bash |
| 313 | compatibility code. It merely makes it possible to install |
| 314 | /bin/bash (sym)link and run scripts which start with |
| 315 | #!/bin/bash line. |
| 316 | |
| 317 | Many systems use it in scripts which use bash-specific features, |
| 318 | even simple ones like $RANDOM. Without this option, busybox |
| 319 | can't be used for running them because it won't recongnize |
| 320 | "bash" as a supported applet name. |
| 321 | |
| 322 | config BUSYBOX_CONFIG_FEATURE_BASH_IS_ASH |
| 323 | depends on BUSYBOX_CONFIG_ASH |
| 324 | bool "ash" |
| 325 | depends on !BUSYBOX_CONFIG_NOMMU |
| 326 | |
| 327 | config BUSYBOX_CONFIG_FEATURE_BASH_IS_HUSH |
| 328 | depends on BUSYBOX_CONFIG_HUSH |
| 329 | bool "hush" |
| 330 | |
| 331 | config BUSYBOX_CONFIG_FEATURE_BASH_IS_NONE |
| 332 | bool "none" |
| 333 | |
| 334 | endchoice |
| 335 | |
| 336 | |
| 337 | config BUSYBOX_CONFIG_SH_MATH_SUPPORT |
| 338 | bool "POSIX math support" |
| 339 | default y |
| 340 | depends on BUSYBOX_CONFIG_ASH || BUSYBOX_CONFIG_HUSH |
| 341 | help |
| 342 | Enable math support in the shell via $((...)) syntax. |
| 343 | |
| 344 | config BUSYBOX_CONFIG_SH_MATH_SUPPORT_64 |
| 345 | bool "Extend POSIX math support to 64 bit" |
| 346 | default y |
| 347 | depends on BUSYBOX_CONFIG_SH_MATH_SUPPORT |
| 348 | help |
| 349 | Enable 64-bit math support in the shell. This will make the shell |
| 350 | slightly larger, but will allow computation with very large numbers. |
| 351 | This is not in POSIX, so do not rely on this in portable code. |
| 352 | |
| 353 | config BUSYBOX_CONFIG_FEATURE_SH_EXTRA_QUIET |
| 354 | bool "Hide message on interactive shell startup" |
| 355 | default n |
| 356 | depends on BUSYBOX_CONFIG_HUSH || BUSYBOX_CONFIG_ASH |
| 357 | help |
| 358 | Remove the busybox introduction when starting a shell. |
| 359 | |
| 360 | config BUSYBOX_CONFIG_FEATURE_SH_STANDALONE |
| 361 | bool "Standalone shell" |
| 362 | default n |
| 363 | depends on (BUSYBOX_CONFIG_HUSH || BUSYBOX_CONFIG_ASH) && BUSYBOX_CONFIG_FEATURE_PREFER_APPLETS |
| 364 | help |
| 365 | This option causes busybox shells to use busybox applets |
| 366 | in preference to executables in the PATH whenever possible. For |
| 367 | example, entering the command 'ifconfig' into the shell would cause |
| 368 | busybox to use the ifconfig busybox applet. Specifying the fully |
| 369 | qualified executable name, such as '/sbin/ifconfig' will still |
| 370 | execute the /sbin/ifconfig executable on the filesystem. This option |
| 371 | is generally used when creating a statically linked version of busybox |
| 372 | for use as a rescue shell, in the event that you screw up your system. |
| 373 | |
| 374 | This is implemented by re-execing /proc/self/exe (typically) |
| 375 | with right parameters. Some selected applets ("NOFORK" applets) |
| 376 | can even be executed without creating new process. |
| 377 | Instead, busybox will call <applet>_main() internally. |
| 378 | |
| 379 | However, this causes problems in chroot jails without mounted /proc |
| 380 | and with ps/top (command name can be shown as 'exe' for applets |
| 381 | started this way). |
| 382 | # untrue? |
| 383 | # Note that this will *also* cause applets to take precedence |
| 384 | # over shell builtins of the same name. So turning this on will |
| 385 | # eliminate any performance gained by turning on the builtin "echo" |
| 386 | # and "test" commands in ash. |
| 387 | # untrue? |
| 388 | # Note that when using this option, the shell will attempt to directly |
| 389 | # run '/bin/busybox'. If you do not have the busybox binary sitting in |
| 390 | # that exact location with that exact name, this option will not work at |
| 391 | # all. |
| 392 | |
| 393 | config BUSYBOX_CONFIG_FEATURE_SH_NOFORK |
| 394 | bool "Run 'nofork' applets directly" |
| 395 | default n |
| 396 | depends on (BUSYBOX_CONFIG_HUSH || BUSYBOX_CONFIG_ASH) && BUSYBOX_CONFIG_FEATURE_PREFER_APPLETS |
| 397 | help |
| 398 | This option causes busybox shells [currently only ash] |
| 399 | to not execute typical fork/exec/wait sequence, but call <applet>_main |
| 400 | directly, if possible. (Sometimes it is not possible: for example, |
| 401 | this is not possible in pipes). |
| 402 | |
| 403 | This will be done only for some applets (those which are marked |
| 404 | NOFORK in include/applets.h). |
| 405 | |
| 406 | This may significantly speed up some shell scripts. |
| 407 | |
| 408 | This feature is relatively new. Use with care. |
| 409 | |
| 410 | endmenu |
| 411 | |
