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>
37 #include "builtins/common.h"
40 #include "execute_cmd.h"
43 # include "bashhist.h"
46 extern int EOF_reached;
47 extern int indirection_level;
48 extern int posixly_correct;
49 extern int subshell_environment, running_under_emacs;
50 extern int last_command_exit_value, stdin_redir;
51 extern int need_here_doc;
52 extern int current_command_number, current_command_line_count, line_number;
53 extern int expand_aliases;
55 static void send_pwd_to_eterm __P((void));
56 static sighandler alrm_catcher __P((int));
58 /* Read and execute commands until EOF is reached. This assumes that
59 the input source has already been initialized. */
63 int our_indirection_level;
64 COMMAND *current_command = (COMMAND *)NULL;
66 USE_VAR(current_command);
68 our_indirection_level = ++indirection_level;
70 while (EOF_Reached == 0)
74 code = setjmp (top_level);
76 #if defined (PROCESS_SUBSTITUTION)
78 #endif /* PROCESS_SUBSTITUTION */
80 if (interactive_shell && signal_is_ignored (SIGINT) == 0)
81 set_signal_handler (SIGINT, sigint_sighandler);
83 if (code != NOT_JUMPED)
85 indirection_level = our_indirection_level;
89 /* Some kind of throw to top_level has occured. */
92 current_command = (COMMAND *)NULL;
93 if (exit_immediately_on_error)
94 variable_context = 0; /* not in a function */
99 last_command_exit_value = 1;
100 if (subshell_environment)
102 current_command = (COMMAND *)NULL;
106 /* Obstack free command elements, etc. */
109 dispose_command (current_command);
110 current_command = (COMMAND *)NULL;
115 command_error ("reader_loop", CMDERR_BADJUMP, code, 0);
121 dispose_used_env_vars ();
123 #if (defined (ultrix) && defined (mips)) || defined (C_ALLOCA)
124 /* Attempt to reclaim memory allocated with alloca (). */
128 if (read_command () == 0)
130 if (interactive_shell == 0 && read_but_dont_execute)
132 last_command_exit_value = EXECUTION_SUCCESS;
133 dispose_command (global_command);
134 global_command = (COMMAND *)NULL;
136 else if (current_command = global_command)
138 global_command = (COMMAND *)NULL;
139 current_command_number++;
143 execute_command (current_command);
148 dispose_command (current_command);
149 current_command = (COMMAND *)NULL;
157 /* Parse error, maybe discard rest of stream if not interactive. */
158 if (interactive == 0)
161 if (just_one_command)
165 return (last_command_exit_value);
172 printf ("\007timed out waiting for input: auto-logout\n");
173 jump_to_top_level (EXITPROG);
177 /* Send an escape sequence to emacs term mode to tell it the
178 current working directory. */
184 pwd = get_string_value ("PWD");
186 pwd = get_working_directory ("eterm");
187 fprintf (stderr, "\032/%s\n", pwd);
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. */
198 char *command_to_execute;
201 run_pending_traps ();
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)
208 command_to_execute = get_string_value ("PROMPT_COMMAND");
209 if (command_to_execute)
210 execute_prompt_command (command_to_execute);
212 if (running_under_emacs == 2)
213 send_pwd_to_eterm (); /* Yuck */
216 current_command_line_count = 0;
220 gather_here_documents ();
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. */
231 SHELL_VAR *tmout_var;
232 int tmout_len, result;
233 SigHandler *old_alrm;
235 set_current_prompt_level (1);
236 global_command = (COMMAND *)NULL;
238 /* Only do timeouts if interactive. */
239 tmout_var = (SHELL_VAR *)NULL;
241 old_alrm = (SigHandler *)NULL;
245 tmout_var = find_variable ("TMOUT");
247 if (tmout_var && var_isset (tmout_var))
249 tmout_len = atoi (value_cell (tmout_var));
252 old_alrm = set_signal_handler (SIGALRM, alrm_catcher);
260 current_command_line_count = 0;
261 result = parse_command ();
263 if (interactive && tmout_var && (tmout_len > 0))
266 set_signal_handler (SIGALRM, old_alrm);