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Commit | Line | Data |
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bb70624e | 1 | /* eval.c -- reading and evaluating commands. */ |
ccc6cda3 | 2 | |
bb70624e | 3 | /* Copyright (C) 1996 Free Software Foundation, Inc. |
ccc6cda3 | 4 | |
bb70624e | 5 | This file is part of GNU Bash, the Bourne Again SHell. |
ccc6cda3 | 6 | |
bb70624e JA |
7 | Bash is free software; you can redistribute it and/or modify it |
8 | under the terms of the GNU General Public License as published by | |
9 | the Free Software Foundation; either version 2, or (at your option) | |
10 | any later version. | |
ccc6cda3 | 11 | |
bb70624e JA |
12 | Bash is distributed in the hope that it will be useful, but WITHOUT |
13 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY | |
14 | or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public | |
15 | License for more details. | |
ccc6cda3 | 16 | |
bb70624e JA |
17 | You should have received a copy of the GNU General Public License |
18 | along with Bash; see the file COPYING. If not, write to the Free | |
19 | Software Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA. */ | |
ccc6cda3 JA |
20 | |
21 | #include "config.h" | |
22 | ||
23 | #if defined (HAVE_UNISTD_H) | |
cce855bc JA |
24 | # ifdef _MINIX |
25 | # include <sys/types.h> | |
26 | # endif | |
ccc6cda3 JA |
27 | # include <unistd.h> |
28 | #endif | |
29 | ||
30 | #include "bashansi.h" | |
31 | #include <stdio.h> | |
32 | ||
33 | #include "shell.h" | |
34 | #include "flags.h" | |
35 | #include "trap.h" | |
36 | ||
37 | #include "builtins/common.h" | |
38 | ||
39 | #include "input.h" | |
40 | #include "execute_cmd.h" | |
41 | ||
b72432fd JA |
42 | #if defined (HISTORY) |
43 | # include "bashhist.h" | |
44 | #endif | |
45 | ||
ccc6cda3 | 46 | extern int EOF_reached; |
f73dda09 | 47 | extern int indirection_level; |
bb70624e | 48 | extern int posixly_correct; |
ccc6cda3 | 49 | extern int subshell_environment, running_under_emacs; |
d166f048 | 50 | extern int last_command_exit_value, stdin_redir; |
ccc6cda3 JA |
51 | extern int need_here_doc; |
52 | extern int current_command_number, current_command_line_count, line_number; | |
ccc6cda3 JA |
53 | extern int expand_aliases; |
54 | ||
7117c2d2 JA |
55 | static void send_pwd_to_eterm __P((void)); |
56 | static sighandler alrm_catcher __P((int)); | |
57 | ||
ccc6cda3 JA |
58 | /* Read and execute commands until EOF is reached. This assumes that |
59 | the input source has already been initialized. */ | |
60 | int | |
61 | reader_loop () | |
62 | { | |
63 | int our_indirection_level; | |
64 | COMMAND *current_command = (COMMAND *)NULL; | |
65 | ||
f73dda09 JA |
66 | USE_VAR(current_command); |
67 | ||
ccc6cda3 JA |
68 | our_indirection_level = ++indirection_level; |
69 | ||
70 | while (EOF_Reached == 0) | |
71 | { | |
72 | int code; | |
73 | ||
74 | code = setjmp (top_level); | |
75 | ||
76 | #if defined (PROCESS_SUBSTITUTION) | |
77 | unlink_fifo_list (); | |
78 | #endif /* PROCESS_SUBSTITUTION */ | |
79 | ||
80 | if (interactive_shell && signal_is_ignored (SIGINT) == 0) | |
81 | set_signal_handler (SIGINT, sigint_sighandler); | |
82 | ||
83 | if (code != NOT_JUMPED) | |
84 | { | |
85 | indirection_level = our_indirection_level; | |
86 | ||
87 | switch (code) | |
88 | { | |
89 | /* Some kind of throw to top_level has occured. */ | |
90 | case FORCE_EOF: | |
91 | case EXITPROG: | |
92 | current_command = (COMMAND *)NULL; | |
bb70624e JA |
93 | if (exit_immediately_on_error) |
94 | variable_context = 0; /* not in a function */ | |
ccc6cda3 JA |
95 | EOF_Reached = EOF; |
96 | goto exec_done; | |
97 | ||
98 | case DISCARD: | |
99 | last_command_exit_value = 1; | |
100 | if (subshell_environment) | |
101 | { | |
102 | current_command = (COMMAND *)NULL; | |
103 | EOF_Reached = EOF; | |
104 | goto exec_done; | |
105 | } | |
106 | /* Obstack free command elements, etc. */ | |
107 | if (current_command) | |
108 | { | |
109 | dispose_command (current_command); | |
110 | current_command = (COMMAND *)NULL; | |
111 | } | |
112 | break; | |
113 | ||
114 | default: | |
b72432fd | 115 | command_error ("reader_loop", CMDERR_BADJUMP, code, 0); |
ccc6cda3 JA |
116 | } |
117 | } | |
118 | ||
119 | executing = 0; | |
7117c2d2 JA |
120 | if (temporary_env) |
121 | dispose_used_env_vars (); | |
ccc6cda3 JA |
122 | |
123 | #if (defined (ultrix) && defined (mips)) || defined (C_ALLOCA) | |
124 | /* Attempt to reclaim memory allocated with alloca (). */ | |
125 | (void) alloca (0); | |
126 | #endif | |
127 | ||
128 | if (read_command () == 0) | |
129 | { | |
130 | if (interactive_shell == 0 && read_but_dont_execute) | |
131 | { | |
132 | last_command_exit_value = EXECUTION_SUCCESS; | |
133 | dispose_command (global_command); | |
134 | global_command = (COMMAND *)NULL; | |
135 | } | |
136 | else if (current_command = global_command) | |
137 | { | |
138 | global_command = (COMMAND *)NULL; | |
139 | current_command_number++; | |
140 | ||
141 | executing = 1; | |
d166f048 | 142 | stdin_redir = 0; |
ccc6cda3 JA |
143 | execute_command (current_command); |
144 | ||
145 | exec_done: | |
146 | if (current_command) | |
28ef6c31 | 147 | { |
ccc6cda3 JA |
148 | dispose_command (current_command); |
149 | current_command = (COMMAND *)NULL; | |
28ef6c31 | 150 | } |
ccc6cda3 JA |
151 | |
152 | QUIT; | |
153 | } | |
154 | } | |
155 | else | |
156 | { | |
157 | /* Parse error, maybe discard rest of stream if not interactive. */ | |
158 | if (interactive == 0) | |
159 | EOF_Reached = EOF; | |
160 | } | |
161 | if (just_one_command) | |
162 | EOF_Reached = EOF; | |
163 | } | |
164 | indirection_level--; | |
165 | return (last_command_exit_value); | |
166 | } | |
167 | ||
168 | static sighandler | |
169 | alrm_catcher(i) | |
170 | int i; | |
171 | { | |
b72432fd | 172 | printf ("\007timed out waiting for input: auto-logout\n"); |
ccc6cda3 JA |
173 | jump_to_top_level (EXITPROG); |
174 | SIGRETURN (0); | |
175 | } | |
176 | ||
177 | /* Send an escape sequence to emacs term mode to tell it the | |
178 | current working directory. */ | |
179 | static void | |
180 | send_pwd_to_eterm () | |
181 | { | |
182 | char *pwd; | |
183 | ||
184 | pwd = get_string_value ("PWD"); | |
185 | if (pwd == 0) | |
186 | pwd = get_working_directory ("eterm"); | |
187 | fprintf (stderr, "\032/%s\n", pwd); | |
188 | } | |
189 | ||
190 | /* Call the YACC-generated parser and return the status of the parse. | |
191 | Input is read from the current input stream (bash_input). yyparse | |
192 | leaves the parsed command in the global variable GLOBAL_COMMAND. | |
193 | This is where PROMPT_COMMAND is executed. */ | |
194 | int | |
195 | parse_command () | |
196 | { | |
197 | int r; | |
198 | char *command_to_execute; | |
199 | ||
200 | need_here_doc = 0; | |
201 | run_pending_traps (); | |
202 | ||
203 | /* Allow the execution of a random command just before the printing | |
204 | of each primary prompt. If the shell variable PROMPT_COMMAND | |
205 | is set then the value of it is the command to execute. */ | |
206 | if (interactive && bash_input.type != st_string) | |
207 | { | |
208 | command_to_execute = get_string_value ("PROMPT_COMMAND"); | |
209 | if (command_to_execute) | |
210 | execute_prompt_command (command_to_execute); | |
211 | ||
212 | if (running_under_emacs == 2) | |
213 | send_pwd_to_eterm (); /* Yuck */ | |
214 | } | |
215 | ||
216 | current_command_line_count = 0; | |
217 | r = yyparse (); | |
218 | ||
219 | if (need_here_doc) | |
220 | gather_here_documents (); | |
221 | ||
222 | return (r); | |
223 | } | |
224 | ||
225 | /* Read and parse a command, returning the status of the parse. The command | |
226 | is left in the globval variable GLOBAL_COMMAND for use by reader_loop. | |
227 | This is where the shell timeout code is executed. */ | |
228 | int | |
229 | read_command () | |
230 | { | |
231 | SHELL_VAR *tmout_var; | |
232 | int tmout_len, result; | |
233 | SigHandler *old_alrm; | |
234 | ||
bb70624e | 235 | set_current_prompt_level (1); |
ccc6cda3 JA |
236 | global_command = (COMMAND *)NULL; |
237 | ||
238 | /* Only do timeouts if interactive. */ | |
239 | tmout_var = (SHELL_VAR *)NULL; | |
240 | tmout_len = 0; | |
f73dda09 | 241 | old_alrm = (SigHandler *)NULL; |
ccc6cda3 JA |
242 | |
243 | if (interactive) | |
244 | { | |
245 | tmout_var = find_variable ("TMOUT"); | |
ccc6cda3 | 246 | |
7117c2d2 | 247 | if (tmout_var && var_isset (tmout_var)) |
ccc6cda3 | 248 | { |
7117c2d2 | 249 | tmout_len = atoi (value_cell (tmout_var)); |
ccc6cda3 JA |
250 | if (tmout_len > 0) |
251 | { | |
252 | old_alrm = set_signal_handler (SIGALRM, alrm_catcher); | |
253 | alarm (tmout_len); | |
254 | } | |
255 | } | |
256 | } | |
257 | ||
258 | QUIT; | |
259 | ||
260 | current_command_line_count = 0; | |
261 | result = parse_command (); | |
262 | ||
263 | if (interactive && tmout_var && (tmout_len > 0)) | |
264 | { | |
265 | alarm(0); | |
266 | set_signal_handler (SIGALRM, old_alrm); | |
267 | } | |
268 | ||
269 | return (result); | |
270 | } |