1 /* eval.c -- reading and evaluating commands. */
3 /* Copyright (C) 1996 Free Software Foundation, Inc.
5 This file is part of GNU Bash, the Bourne Again SHell.
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)
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.
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. */
23 #if defined (HAVE_UNISTD_H)
25 # include <sys/types.h>
39 #include "builtins/common.h"
42 #include "execute_cmd.h"
45 # include "bashhist.h"
48 extern int EOF_reached;
49 extern int indirection_level;
50 extern int posixly_correct;
51 extern int subshell_environment, running_under_emacs;
52 extern int last_command_exit_value, stdin_redir;
53 extern int need_here_doc;
54 extern int current_command_number, current_command_line_count, line_number;
55 extern int expand_aliases;
57 static void send_pwd_to_eterm __P((void));
58 static sighandler alrm_catcher __P((int));
60 /* Read and execute commands until EOF is reached. This assumes that
61 the input source has already been initialized. */
65 int our_indirection_level;
66 COMMAND *current_command = (COMMAND *)NULL;
68 USE_VAR(current_command);
70 our_indirection_level = ++indirection_level;
72 while (EOF_Reached == 0)
76 code = setjmp (top_level);
78 #if defined (PROCESS_SUBSTITUTION)
80 #endif /* PROCESS_SUBSTITUTION */
82 if (interactive_shell && signal_is_ignored (SIGINT) == 0)
83 set_signal_handler (SIGINT, sigint_sighandler);
85 if (code != NOT_JUMPED)
87 indirection_level = our_indirection_level;
91 /* Some kind of throw to top_level has occured. */
95 current_command = (COMMAND *)NULL;
96 if (exit_immediately_on_error)
97 variable_context = 0; /* not in a function */
102 last_command_exit_value = 1;
103 if (subshell_environment)
105 current_command = (COMMAND *)NULL;
109 /* Obstack free command elements, etc. */
112 dispose_command (current_command);
113 current_command = (COMMAND *)NULL;
118 command_error ("reader_loop", CMDERR_BADJUMP, code, 0);
124 dispose_used_env_vars ();
126 #if (defined (ultrix) && defined (mips)) || defined (C_ALLOCA)
127 /* Attempt to reclaim memory allocated with alloca (). */
131 if (read_command () == 0)
133 if (interactive_shell == 0 && read_but_dont_execute)
135 last_command_exit_value = EXECUTION_SUCCESS;
136 dispose_command (global_command);
137 global_command = (COMMAND *)NULL;
139 else if (current_command = global_command)
141 global_command = (COMMAND *)NULL;
142 current_command_number++;
146 execute_command (current_command);
151 dispose_command (current_command);
152 current_command = (COMMAND *)NULL;
160 /* Parse error, maybe discard rest of stream if not interactive. */
161 if (interactive == 0)
164 if (just_one_command)
168 return (last_command_exit_value);
175 printf (_("\007timed out waiting for input: auto-logout\n"));
176 bash_logout (); /* run ~/.bash_logout if this is a login shell */
177 jump_to_top_level (EXITPROG);
181 /* Send an escape sequence to emacs term mode to tell it the
182 current working directory. */
188 pwd = get_string_value ("PWD");
190 pwd = get_working_directory ("eterm");
191 fprintf (stderr, "\032/%s\n", pwd);
194 /* Call the YACC-generated parser and return the status of the parse.
195 Input is read from the current input stream (bash_input). yyparse
196 leaves the parsed command in the global variable GLOBAL_COMMAND.
197 This is where PROMPT_COMMAND is executed. */
202 char *command_to_execute;
205 run_pending_traps ();
207 /* Allow the execution of a random command just before the printing
208 of each primary prompt. If the shell variable PROMPT_COMMAND
209 is set then the value of it is the command to execute. */
210 if (interactive && bash_input.type != st_string)
212 command_to_execute = get_string_value ("PROMPT_COMMAND");
213 if (command_to_execute)
214 execute_prompt_command (command_to_execute);
216 if (running_under_emacs == 2)
217 send_pwd_to_eterm (); /* Yuck */
220 current_command_line_count = 0;
224 gather_here_documents ();
229 /* Read and parse a command, returning the status of the parse. The command
230 is left in the globval variable GLOBAL_COMMAND for use by reader_loop.
231 This is where the shell timeout code is executed. */
235 SHELL_VAR *tmout_var;
236 int tmout_len, result;
237 SigHandler *old_alrm;
239 set_current_prompt_level (1);
240 global_command = (COMMAND *)NULL;
242 /* Only do timeouts if interactive. */
243 tmout_var = (SHELL_VAR *)NULL;
245 old_alrm = (SigHandler *)NULL;
249 tmout_var = find_variable ("TMOUT");
251 if (tmout_var && var_isset (tmout_var))
253 tmout_len = atoi (value_cell (tmout_var));
256 old_alrm = set_signal_handler (SIGALRM, alrm_catcher);
264 current_command_line_count = 0;
265 result = parse_command ();
267 if (interactive && tmout_var && (tmout_len > 0))
270 set_signal_handler (SIGALRM, old_alrm);