]>
Commit | Line | Data |
---|---|---|
1 | /* Evaluate a string as one or more shell commands. | |
2 | ||
3 | Copyright (C) 1996-2005 Free Software Foundation, Inc. | |
4 | ||
5 | This file is part of GNU Bash, the Bourne Again SHell. | |
6 | ||
7 | Bash is free software; you can redistribute it and/or modify it under | |
8 | the terms of the GNU General Public License as published by the Free | |
9 | Software Foundation; either version 2, or (at your option) any later | |
10 | version. | |
11 | ||
12 | Bash is distributed in the hope that it will be useful, but WITHOUT ANY | |
13 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
14 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
15 | for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License along | |
18 | with Bash; see the file COPYING. If not, write to the Free Software | |
19 | Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA. */ | |
20 | ||
21 | #include <config.h> | |
22 | ||
23 | #if defined (HAVE_UNISTD_H) | |
24 | # ifdef _MINIX | |
25 | # include <sys/types.h> | |
26 | # endif | |
27 | # include <unistd.h> | |
28 | #endif | |
29 | ||
30 | #include <stdio.h> | |
31 | #include <signal.h> | |
32 | ||
33 | #include <errno.h> | |
34 | ||
35 | #include "filecntl.h" | |
36 | #include "../bashansi.h" | |
37 | ||
38 | #include "../shell.h" | |
39 | #include "../jobs.h" | |
40 | #include "../builtins.h" | |
41 | #include "../flags.h" | |
42 | #include "../input.h" | |
43 | #include "../execute_cmd.h" | |
44 | #include "../redir.h" | |
45 | #include "../trap.h" | |
46 | ||
47 | #if defined (HISTORY) | |
48 | # include "../bashhist.h" | |
49 | #endif | |
50 | ||
51 | #include "common.h" | |
52 | ||
53 | #if !defined (errno) | |
54 | extern int errno; | |
55 | #endif | |
56 | ||
57 | #define IS_BUILTIN(s) (builtin_address_internal(s, 0) != (struct builtin *)NULL) | |
58 | ||
59 | extern int indirection_level, subshell_environment; | |
60 | extern int line_number; | |
61 | extern int last_command_exit_value; | |
62 | extern int running_trap; | |
63 | extern int loop_level; | |
64 | extern int posixly_correct; | |
65 | ||
66 | int parse_and_execute_level = 0; | |
67 | ||
68 | static int cat_file __P((REDIRECT *)); | |
69 | ||
70 | #if defined (HISTORY) | |
71 | static void | |
72 | set_history_remembering () | |
73 | { | |
74 | remember_on_history = enable_history_list; | |
75 | } | |
76 | #endif | |
77 | ||
78 | /* How to force parse_and_execute () to clean up after itself. */ | |
79 | void | |
80 | parse_and_execute_cleanup () | |
81 | { | |
82 | if (running_trap) | |
83 | { | |
84 | run_trap_cleanup (running_trap - 1); | |
85 | unfreeze_jobs_list (); | |
86 | } | |
87 | run_unwind_frame ("parse_and_execute_top"); | |
88 | } | |
89 | ||
90 | /* Parse and execute the commands in STRING. Returns whatever | |
91 | execute_command () returns. This frees STRING. FLAGS is a | |
92 | flags word; look in common.h for the possible values. Actions | |
93 | are: | |
94 | (flags & SEVAL_NONINT) -> interactive = 0; | |
95 | (flags & SEVAL_INTERACT) -> interactive = 1; | |
96 | (flags & SEVAL_NOHIST) -> call bash_history_disable () | |
97 | (flags & SEVAL_NOFREE) -> don't free STRING when finished | |
98 | (flags & SEVAL_RESETLINE) -> reset line_number to 1 | |
99 | */ | |
100 | ||
101 | int | |
102 | parse_and_execute (string, from_file, flags) | |
103 | char *string; | |
104 | const char *from_file; | |
105 | int flags; | |
106 | { | |
107 | int code, x, lreset; | |
108 | volatile int should_jump_to_top_level, last_result; | |
109 | char *orig_string; | |
110 | COMMAND *volatile command; | |
111 | ||
112 | orig_string = string; | |
113 | /* Unwind protect this invocation of parse_and_execute (). */ | |
114 | begin_unwind_frame ("parse_and_execute_top"); | |
115 | unwind_protect_int (parse_and_execute_level); | |
116 | unwind_protect_jmp_buf (top_level); | |
117 | unwind_protect_int (indirection_level); | |
118 | unwind_protect_int (line_number); | |
119 | unwind_protect_int (loop_level); | |
120 | if (flags & (SEVAL_NONINT|SEVAL_INTERACT)) | |
121 | unwind_protect_int (interactive); | |
122 | ||
123 | lreset = flags & SEVAL_RESETLINE; | |
124 | ||
125 | #if defined (HISTORY) | |
126 | if (parse_and_execute_level == 0) | |
127 | add_unwind_protect (set_history_remembering, (char *)NULL); | |
128 | else | |
129 | unwind_protect_int (remember_on_history); /* can be used in scripts */ | |
130 | # if defined (BANG_HISTORY) | |
131 | if (interactive_shell) | |
132 | { | |
133 | unwind_protect_int (history_expansion_inhibited); | |
134 | } | |
135 | # endif /* BANG_HISTORY */ | |
136 | #endif /* HISTORY */ | |
137 | ||
138 | if (interactive_shell) | |
139 | { | |
140 | x = get_current_prompt_level (); | |
141 | add_unwind_protect (set_current_prompt_level, x); | |
142 | } | |
143 | ||
144 | add_unwind_protect (pop_stream, (char *)NULL); | |
145 | if (orig_string && ((flags & SEVAL_NOFREE) == 0)) | |
146 | add_unwind_protect (xfree, orig_string); | |
147 | end_unwind_frame (); | |
148 | ||
149 | parse_and_execute_level++; | |
150 | ||
151 | /* Reset the line number if the caller wants us to. If we don't reset the | |
152 | line number, we have to subtract one, because we will add one just | |
153 | before executing the next command (resetting the line number sets it to | |
154 | 0; the first line number is 1). */ | |
155 | push_stream (lreset); | |
156 | if (lreset == 0) | |
157 | line_number--; | |
158 | ||
159 | indirection_level++; | |
160 | if (flags & (SEVAL_NONINT|SEVAL_INTERACT)) | |
161 | interactive = (flags & SEVAL_NONINT) ? 0 : 1; | |
162 | ||
163 | #if defined (HISTORY) | |
164 | if (flags & SEVAL_NOHIST) | |
165 | bash_history_disable (); | |
166 | #endif /* HISTORY */ | |
167 | ||
168 | code = should_jump_to_top_level = 0; | |
169 | last_result = EXECUTION_SUCCESS; | |
170 | ||
171 | with_input_from_string (string, from_file); | |
172 | while (*(bash_input.location.string)) | |
173 | { | |
174 | command = (COMMAND *)NULL; | |
175 | ||
176 | if (interrupt_state) | |
177 | { | |
178 | last_result = EXECUTION_FAILURE; | |
179 | break; | |
180 | } | |
181 | ||
182 | /* Provide a location for functions which `longjmp (top_level)' to | |
183 | jump to. This prevents errors in substitution from restarting | |
184 | the reader loop directly, for example. */ | |
185 | code = setjmp (top_level); | |
186 | ||
187 | if (code) | |
188 | { | |
189 | should_jump_to_top_level = 0; | |
190 | switch (code) | |
191 | { | |
192 | case FORCE_EOF: | |
193 | case ERREXIT: | |
194 | case EXITPROG: | |
195 | if (command) | |
196 | run_unwind_frame ("pe_dispose"); | |
197 | /* Remember to call longjmp (top_level) after the old | |
198 | value for it is restored. */ | |
199 | should_jump_to_top_level = 1; | |
200 | goto out; | |
201 | ||
202 | case DISCARD: | |
203 | if (command) | |
204 | run_unwind_frame ("pe_dispose"); | |
205 | last_result = last_command_exit_value = EXECUTION_FAILURE; /* XXX */ | |
206 | if (subshell_environment) | |
207 | { | |
208 | should_jump_to_top_level = 1; | |
209 | goto out; | |
210 | } | |
211 | else | |
212 | { | |
213 | #if 0 | |
214 | dispose_command (command); /* pe_dispose does this */ | |
215 | #endif | |
216 | continue; | |
217 | } | |
218 | ||
219 | default: | |
220 | command_error ("parse_and_execute", CMDERR_BADJUMP, code, 0); | |
221 | break; | |
222 | } | |
223 | } | |
224 | ||
225 | if (parse_command () == 0) | |
226 | { | |
227 | if (interactive_shell == 0 && read_but_dont_execute) | |
228 | { | |
229 | last_result = EXECUTION_SUCCESS; | |
230 | dispose_command (global_command); | |
231 | global_command = (COMMAND *)NULL; | |
232 | } | |
233 | else if (command = global_command) | |
234 | { | |
235 | struct fd_bitmap *bitmap; | |
236 | ||
237 | bitmap = new_fd_bitmap (FD_BITMAP_SIZE); | |
238 | begin_unwind_frame ("pe_dispose"); | |
239 | add_unwind_protect (dispose_fd_bitmap, bitmap); | |
240 | add_unwind_protect (dispose_command, command); /* XXX */ | |
241 | ||
242 | global_command = (COMMAND *)NULL; | |
243 | ||
244 | #if defined (ONESHOT) | |
245 | /* | |
246 | * IF | |
247 | * we were invoked as `bash -c' (startup_state == 2) AND | |
248 | * parse_and_execute has not been called recursively AND | |
249 | * we're not running a trap AND | |
250 | * we have parsed the full command (string == '\0') AND | |
251 | * we're not going to run the exit trap AND | |
252 | * we have a simple command without redirections AND | |
253 | * the command is not being timed AND | |
254 | * the command's return status is not being inverted | |
255 | * THEN | |
256 | * tell the execution code that we don't need to fork | |
257 | */ | |
258 | if (startup_state == 2 && parse_and_execute_level == 1 && | |
259 | running_trap == 0 && | |
260 | *bash_input.location.string == '\0' && | |
261 | command->type == cm_simple && | |
262 | signal_is_trapped (EXIT_TRAP) == 0 && | |
263 | command->redirects == 0 && command->value.Simple->redirects == 0 && | |
264 | ((command->flags & CMD_TIME_PIPELINE) == 0) && | |
265 | ((command->flags & CMD_INVERT_RETURN) == 0)) | |
266 | { | |
267 | command->flags |= CMD_NO_FORK; | |
268 | command->value.Simple->flags |= CMD_NO_FORK; | |
269 | } | |
270 | #endif /* ONESHOT */ | |
271 | ||
272 | /* See if this is a candidate for $( <file ). */ | |
273 | if (startup_state == 2 && | |
274 | (subshell_environment & SUBSHELL_COMSUB) && | |
275 | *bash_input.location.string == '\0' && | |
276 | command->type == cm_simple && !command->redirects && | |
277 | (command->flags & CMD_TIME_PIPELINE) == 0 && | |
278 | command->value.Simple->words == 0 && | |
279 | command->value.Simple->redirects && | |
280 | command->value.Simple->redirects->next == 0 && | |
281 | command->value.Simple->redirects->instruction == r_input_direction) | |
282 | { | |
283 | int r; | |
284 | r = cat_file (command->value.Simple->redirects); | |
285 | last_result = (r < 0) ? EXECUTION_FAILURE : EXECUTION_SUCCESS; | |
286 | } | |
287 | else | |
288 | last_result = execute_command_internal | |
289 | (command, 0, NO_PIPE, NO_PIPE, bitmap); | |
290 | ||
291 | dispose_command (command); | |
292 | dispose_fd_bitmap (bitmap); | |
293 | discard_unwind_frame ("pe_dispose"); | |
294 | } | |
295 | } | |
296 | else | |
297 | { | |
298 | last_result = EXECUTION_FAILURE; | |
299 | ||
300 | /* Since we are shell compatible, syntax errors in a script | |
301 | abort the execution of the script. Right? */ | |
302 | break; | |
303 | } | |
304 | } | |
305 | ||
306 | out: | |
307 | ||
308 | run_unwind_frame ("parse_and_execute_top"); | |
309 | ||
310 | if (interrupt_state && parse_and_execute_level == 0) | |
311 | { | |
312 | /* An interrupt during non-interactive execution in an | |
313 | interactive shell (e.g. via $PROMPT_COMMAND) should | |
314 | not cause the shell to exit. */ | |
315 | interactive = interactive_shell; | |
316 | throw_to_top_level (); | |
317 | } | |
318 | ||
319 | if (should_jump_to_top_level) | |
320 | jump_to_top_level (code); | |
321 | ||
322 | return (last_result); | |
323 | } | |
324 | ||
325 | /* Handle a $( < file ) command substitution. This expands the filename, | |
326 | returning errors as appropriate, then just cats the file to the standard | |
327 | output. */ | |
328 | static int | |
329 | cat_file (r) | |
330 | REDIRECT *r; | |
331 | { | |
332 | char *fn; | |
333 | int fd, rval; | |
334 | ||
335 | if (r->instruction != r_input_direction) | |
336 | return -1; | |
337 | ||
338 | /* Get the filename. */ | |
339 | if (posixly_correct && !interactive_shell) | |
340 | disallow_filename_globbing++; | |
341 | fn = redirection_expand (r->redirectee.filename); | |
342 | if (posixly_correct && !interactive_shell) | |
343 | disallow_filename_globbing--; | |
344 | ||
345 | if (fn == 0) | |
346 | { | |
347 | redirection_error (r, AMBIGUOUS_REDIRECT); | |
348 | return -1; | |
349 | } | |
350 | ||
351 | fd = open(fn, O_RDONLY); | |
352 | if (fd < 0) | |
353 | { | |
354 | file_error (fn); | |
355 | free (fn); | |
356 | return -1; | |
357 | } | |
358 | ||
359 | rval = zcatfd (fd, 1, fn); | |
360 | ||
361 | free (fn); | |
362 | close (fd); | |
363 | ||
364 | return (rval); | |
365 | } |