1 | /* flags.c -- Everything about flags except the `set' command. That |
---|
2 | is in builtins.c */ |
---|
3 | |
---|
4 | /* Copyright (C) 1987,1989 Free Software Foundation, Inc. |
---|
5 | |
---|
6 | This file is part of GNU Bash, the Bourne Again SHell. |
---|
7 | |
---|
8 | Bash is free software; you can redistribute it and/or modify it under |
---|
9 | the terms of the GNU General Public License as published by the Free |
---|
10 | Software Foundation; either version 2, or (at your option) any later |
---|
11 | version. |
---|
12 | |
---|
13 | Bash is distributed in the hope that it will be useful, but WITHOUT ANY |
---|
14 | WARRANTY; without even the implied warranty of MERCHANTABILITY or |
---|
15 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
---|
16 | for more details. |
---|
17 | |
---|
18 | You should have received a copy of the GNU General Public License along |
---|
19 | with Bash; see the file COPYING. If not, write to the Free Software |
---|
20 | Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA. */ |
---|
21 | |
---|
22 | /* Flags hacking. */ |
---|
23 | #include "config.h" |
---|
24 | #if defined (HAVE_UNISTD_H) |
---|
25 | # include <unistd.h> |
---|
26 | #endif |
---|
27 | |
---|
28 | #include "shell.h" |
---|
29 | #include "flags.h" |
---|
30 | |
---|
31 | #if defined (BANG_HISTORY) |
---|
32 | # include "bashhist.h" |
---|
33 | #endif |
---|
34 | |
---|
35 | #if defined (JOB_CONTROL) |
---|
36 | extern int set_job_control __P((int)); |
---|
37 | #endif |
---|
38 | |
---|
39 | #if defined (RESTRICTED_SHELL) |
---|
40 | extern char *shell_name; |
---|
41 | #endif |
---|
42 | |
---|
43 | /* -c, -s invocation options -- not really flags, but they show up in $- */ |
---|
44 | extern int want_pending_command, read_from_stdin; |
---|
45 | |
---|
46 | /* **************************************************************** */ |
---|
47 | /* */ |
---|
48 | /* The Standard Sh Flags. */ |
---|
49 | /* */ |
---|
50 | /* **************************************************************** */ |
---|
51 | |
---|
52 | /* Non-zero means automatically mark variables which are modified or created |
---|
53 | as auto export variables. */ |
---|
54 | int mark_modified_vars = 0; |
---|
55 | |
---|
56 | /* Non-zero causes asynchronous job notification. Otherwise, job state |
---|
57 | notification only takes place just before a primary prompt is printed. */ |
---|
58 | int asynchronous_notification = 0; |
---|
59 | |
---|
60 | /* Non-zero means exit immediately if a command exits with a non-zero |
---|
61 | exit status. */ |
---|
62 | int exit_immediately_on_error = 0; |
---|
63 | |
---|
64 | /* Non-zero means disable filename globbing. */ |
---|
65 | int disallow_filename_globbing = 0; |
---|
66 | |
---|
67 | /* Non-zero means that all keyword arguments are placed into the environment |
---|
68 | for a command, not just those that appear on the line before the command |
---|
69 | name. */ |
---|
70 | int place_keywords_in_env = 0; |
---|
71 | |
---|
72 | /* Non-zero means read commands, but don't execute them. This is useful |
---|
73 | for debugging shell scripts that should do something hairy and possibly |
---|
74 | destructive. */ |
---|
75 | int read_but_dont_execute = 0; |
---|
76 | |
---|
77 | /* Non-zero means end of file is after one command. */ |
---|
78 | int just_one_command = 0; |
---|
79 | |
---|
80 | /* Non-zero means don't overwrite existing files while doing redirections. */ |
---|
81 | int noclobber = 0; |
---|
82 | |
---|
83 | /* Non-zero means trying to get the value of $i where $i is undefined |
---|
84 | causes an error, instead of a null substitution. */ |
---|
85 | int unbound_vars_is_error = 0; |
---|
86 | |
---|
87 | /* Non-zero means type out input lines after you read them. */ |
---|
88 | int echo_input_at_read = 0; |
---|
89 | |
---|
90 | /* Non-zero means type out the command definition after reading, but |
---|
91 | before executing. */ |
---|
92 | int echo_command_at_execute = 0; |
---|
93 | |
---|
94 | /* Non-zero means turn on the job control features. */ |
---|
95 | int jobs_m_flag = 0; |
---|
96 | |
---|
97 | /* Non-zero means this shell is interactive, even if running under a |
---|
98 | pipe. */ |
---|
99 | int forced_interactive = 0; |
---|
100 | |
---|
101 | /* By default, follow the symbolic links as if they were real directories |
---|
102 | while hacking the `cd' command. This means that `cd ..' moves up in |
---|
103 | the string of symbolic links that make up the current directory, instead |
---|
104 | of the absolute directory. The shell variable `nolinks' also controls |
---|
105 | this flag. */ |
---|
106 | int no_symbolic_links = 0; |
---|
107 | |
---|
108 | /* **************************************************************** */ |
---|
109 | /* */ |
---|
110 | /* Non-Standard Flags Follow Here. */ |
---|
111 | /* */ |
---|
112 | /* **************************************************************** */ |
---|
113 | |
---|
114 | #if 0 |
---|
115 | /* Non-zero means do lexical scoping in the body of a FOR command. */ |
---|
116 | int lexical_scoping = 0; |
---|
117 | #endif |
---|
118 | |
---|
119 | /* Non-zero means no such thing as invisible variables. */ |
---|
120 | int no_invisible_vars = 0; |
---|
121 | |
---|
122 | /* Non-zero means look up and remember command names in a hash table, */ |
---|
123 | int hashing_enabled = 1; |
---|
124 | |
---|
125 | #if defined (BANG_HISTORY) |
---|
126 | /* Non-zero means that we are doing history expansion. The default. |
---|
127 | This means !22 gets the 22nd line of history. */ |
---|
128 | int history_expansion = 1; |
---|
129 | #endif /* BANG_HISTORY */ |
---|
130 | |
---|
131 | /* Non-zero means that we allow comments to appear in interactive commands. */ |
---|
132 | int interactive_comments = 1; |
---|
133 | |
---|
134 | #if defined (RESTRICTED_SHELL) |
---|
135 | /* Non-zero means that this shell is `restricted'. A restricted shell |
---|
136 | disallows: changing directories, command or path names containing `/', |
---|
137 | unsetting or resetting the values of $PATH and $SHELL, and any type of |
---|
138 | output redirection. */ |
---|
139 | int restricted = 0; /* currently restricted */ |
---|
140 | int restricted_shell = 0; /* shell was started in restricted mode. */ |
---|
141 | #endif /* RESTRICTED_SHELL */ |
---|
142 | |
---|
143 | /* Non-zero means that this shell is running in `privileged' mode. This |
---|
144 | is required if the shell is to run setuid. If the `-p' option is |
---|
145 | not supplied at startup, and the real and effective uids or gids |
---|
146 | differ, disable_priv_mode is called to relinquish setuid status. */ |
---|
147 | int privileged_mode = 0; |
---|
148 | |
---|
149 | #if defined (BRACE_EXPANSION) |
---|
150 | /* Zero means to disable brace expansion: foo{a,b} -> fooa foob */ |
---|
151 | int brace_expansion = 1; |
---|
152 | #endif |
---|
153 | |
---|
154 | /* **************************************************************** */ |
---|
155 | /* */ |
---|
156 | /* The Flags ALIST. */ |
---|
157 | /* */ |
---|
158 | /* **************************************************************** */ |
---|
159 | |
---|
160 | struct flags_alist shell_flags[] = { |
---|
161 | /* Standard sh flags. */ |
---|
162 | { 'a', &mark_modified_vars }, |
---|
163 | #if defined (JOB_CONTROL) |
---|
164 | { 'b', &asynchronous_notification }, |
---|
165 | #endif /* JOB_CONTROL */ |
---|
166 | { 'e', &exit_immediately_on_error }, |
---|
167 | { 'f', &disallow_filename_globbing }, |
---|
168 | { 'h', &hashing_enabled }, |
---|
169 | { 'i', &forced_interactive }, |
---|
170 | { 'k', &place_keywords_in_env }, |
---|
171 | #if defined (JOB_CONTROL) |
---|
172 | { 'm', &jobs_m_flag }, |
---|
173 | #endif /* JOB_CONTROL */ |
---|
174 | { 'n', &read_but_dont_execute }, |
---|
175 | { 'p', &privileged_mode }, |
---|
176 | #if defined (RESTRICTED_SHELL) |
---|
177 | { 'r', &restricted }, |
---|
178 | #endif /* RESTRICTED_SHELL */ |
---|
179 | { 't', &just_one_command }, |
---|
180 | { 'u', &unbound_vars_is_error }, |
---|
181 | { 'v', &echo_input_at_read }, |
---|
182 | { 'x', &echo_command_at_execute }, |
---|
183 | { 'C', &noclobber }, |
---|
184 | |
---|
185 | /* New flags that control non-standard things. */ |
---|
186 | #if 0 |
---|
187 | { 'l', &lexical_scoping }, |
---|
188 | #endif |
---|
189 | { 'I', &no_invisible_vars }, |
---|
190 | |
---|
191 | { 'P', &no_symbolic_links }, |
---|
192 | |
---|
193 | #if defined (BRACE_EXPANSION) |
---|
194 | { 'B', &brace_expansion }, |
---|
195 | #endif |
---|
196 | |
---|
197 | #if defined (BANG_HISTORY) |
---|
198 | { 'H', &history_expansion }, |
---|
199 | #endif /* BANG_HISTORY */ |
---|
200 | |
---|
201 | {0, (int *)NULL} |
---|
202 | }; |
---|
203 | |
---|
204 | #define NUM_SHELL_FLAGS (sizeof (shell_flags) / sizeof (struct flags_alist)) |
---|
205 | |
---|
206 | char optflags[NUM_SHELL_FLAGS+4] = { '+' }; |
---|
207 | |
---|
208 | int * |
---|
209 | find_flag (name) |
---|
210 | int name; |
---|
211 | { |
---|
212 | int i; |
---|
213 | for (i = 0; shell_flags[i].name; i++) |
---|
214 | { |
---|
215 | if (shell_flags[i].name == name) |
---|
216 | return (shell_flags[i].value); |
---|
217 | } |
---|
218 | return (FLAG_UNKNOWN); |
---|
219 | } |
---|
220 | |
---|
221 | /* Change the state of a flag, and return it's original value, or return |
---|
222 | FLAG_ERROR if there is no flag FLAG. ON_OR_OFF must be either |
---|
223 | FLAG_ON or FLAG_OFF. */ |
---|
224 | int |
---|
225 | change_flag (flag, on_or_off) |
---|
226 | int flag; |
---|
227 | int on_or_off; |
---|
228 | { |
---|
229 | int *value, old_value; |
---|
230 | |
---|
231 | #if defined (RESTRICTED_SHELL) |
---|
232 | /* Don't allow "set +r" in a shell which is `restricted'. */ |
---|
233 | if (restricted && flag == 'r' && on_or_off == FLAG_OFF) |
---|
234 | return (FLAG_ERROR); |
---|
235 | #endif /* RESTRICTED_SHELL */ |
---|
236 | |
---|
237 | value = find_flag (flag); |
---|
238 | |
---|
239 | if ((value == (int *)FLAG_UNKNOWN) || (on_or_off != FLAG_ON && on_or_off != FLAG_OFF)) |
---|
240 | return (FLAG_ERROR); |
---|
241 | |
---|
242 | old_value = *value; |
---|
243 | |
---|
244 | *value = (on_or_off == FLAG_ON) ? 1 : 0; |
---|
245 | |
---|
246 | /* Special cases for a few flags. */ |
---|
247 | switch (flag) |
---|
248 | { |
---|
249 | #if defined (BANG_HISTORY) |
---|
250 | case 'H': |
---|
251 | if (on_or_off == FLAG_ON) |
---|
252 | bash_initialize_history (); |
---|
253 | break; |
---|
254 | #endif |
---|
255 | |
---|
256 | #if defined (JOB_CONTROL) |
---|
257 | case 'm': |
---|
258 | set_job_control (on_or_off == FLAG_ON); |
---|
259 | break; |
---|
260 | #endif /* JOB_CONTROL */ |
---|
261 | |
---|
262 | case 'n': |
---|
263 | if (interactive_shell) |
---|
264 | read_but_dont_execute = 0; |
---|
265 | break; |
---|
266 | |
---|
267 | case 'p': |
---|
268 | if (on_or_off == FLAG_OFF) |
---|
269 | disable_priv_mode (); |
---|
270 | break; |
---|
271 | |
---|
272 | #if defined (RESTRICTED_SHELL) |
---|
273 | case 'r': |
---|
274 | if (on_or_off == FLAG_ON) |
---|
275 | maybe_make_restricted (shell_name); |
---|
276 | break; |
---|
277 | #endif |
---|
278 | |
---|
279 | } |
---|
280 | |
---|
281 | return (old_value); |
---|
282 | } |
---|
283 | |
---|
284 | /* Return a string which is the names of all the currently |
---|
285 | set shell flags. */ |
---|
286 | char * |
---|
287 | which_set_flags () |
---|
288 | { |
---|
289 | char *temp; |
---|
290 | int i, string_index; |
---|
291 | |
---|
292 | temp = (char *)xmalloc (1 + NUM_SHELL_FLAGS + read_from_stdin + want_pending_command); |
---|
293 | for (i = string_index = 0; shell_flags[i].name; i++) |
---|
294 | if (*(shell_flags[i].value)) |
---|
295 | temp[string_index++] = shell_flags[i].name; |
---|
296 | |
---|
297 | if (want_pending_command) |
---|
298 | temp[string_index++] = 'c'; |
---|
299 | if (read_from_stdin) |
---|
300 | temp[string_index++] = 's'; |
---|
301 | |
---|
302 | temp[string_index] = '\0'; |
---|
303 | return (temp); |
---|
304 | } |
---|
305 | |
---|
306 | void |
---|
307 | reset_shell_flags () |
---|
308 | { |
---|
309 | mark_modified_vars = exit_immediately_on_error = disallow_filename_globbing = 0; |
---|
310 | place_keywords_in_env = read_but_dont_execute = just_one_command = 0; |
---|
311 | noclobber = unbound_vars_is_error = echo_input_at_read = 0; |
---|
312 | echo_command_at_execute = jobs_m_flag = forced_interactive = 0; |
---|
313 | no_symbolic_links = no_invisible_vars = privileged_mode = 0; |
---|
314 | |
---|
315 | hashing_enabled = interactive_comments = 1; |
---|
316 | |
---|
317 | #if defined (JOB_CONTROL) |
---|
318 | asynchronous_notification = 0; |
---|
319 | #endif |
---|
320 | |
---|
321 | #if defined (BANG_HISTORY) |
---|
322 | history_expansion = 1; |
---|
323 | #endif |
---|
324 | |
---|
325 | #if defined (BRACE_EXPANSION) |
---|
326 | brace_expansion = 1; |
---|
327 | #endif |
---|
328 | |
---|
329 | #if defined (RESTRICTED_SHELL) |
---|
330 | restricted = 0; |
---|
331 | #endif |
---|
332 | } |
---|
333 | |
---|
334 | void |
---|
335 | initialize_flags () |
---|
336 | { |
---|
337 | register int i; |
---|
338 | |
---|
339 | for (i = 0; shell_flags[i].name; i++) |
---|
340 | optflags[i+1] = shell_flags[i].name; |
---|
341 | optflags[++i] = 'o'; |
---|
342 | optflags[++i] = ';'; |
---|
343 | optflags[i+1] = '\0'; |
---|
344 | } |
---|