1 /* command.h -- The structures used internally to represent commands, and
2 the extern declarations of the functions used to create them. */
4 /* Copyright (C) 1993 Free Software Foundation, Inc.
6 This file is part of GNU Bash, the Bourne Again SHell.
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
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
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. */
22 #if !defined (_COMMAND_H_)
27 /* Instructions describing what kind of thing to do for a redirection. */
29 r_output_direction, r_input_direction, r_inputa_direction,
30 r_appending_to, r_reading_until, r_duplicating_input,
31 r_duplicating_output, r_deblank_reading_until, r_close_this,
32 r_err_and_out, r_input_output, r_output_force,
33 r_duplicating_input_word, r_duplicating_output_word
36 /* Redirection errors. */
37 #define AMBIGUOUS_REDIRECT -1
38 #define NOCLOBBER_REDIRECT -2
39 #define RESTRICTED_REDIRECT -3 /* can only happen in restricted shells. */
40 #define HEREDOC_REDIRECT -4 /* here-doc temp file can't be created */
42 #define OUTPUT_REDIRECT(ri) \
43 (ri == r_output_direction || ri == r_input_output || ri == r_err_and_out)
45 #define INPUT_REDIRECT(ri) \
46 (ri == r_input_direction || ri == r_inputa_direction || ri == r_input_output)
48 #define WRITE_REDIRECT(ri) \
49 (ri == r_output_direction || \
50 ri == r_input_output || \
51 ri == r_err_and_out || \
52 ri == r_appending_to || \
56 enum command_type { cm_for, cm_case, cm_while, cm_if, cm_simple, cm_select,
57 cm_connection, cm_function_def, cm_until, cm_group,
58 cm_arith, cm_cond, cm_arith_for, cm_subshell };
60 /* Possible values for the `flags' field of a WORD_DESC. */
61 #define W_HASDOLLAR 0x01 /* Dollar sign present. */
62 #define W_QUOTED 0x02 /* Some form of quote character is present. */
63 #define W_ASSIGNMENT 0x04 /* This word is a variable assignment. */
64 #define W_GLOBEXP 0x08 /* This word is the result of a glob expansion. */
65 #define W_NOSPLIT 0x10 /* Do not perform word splitting on this word. */
66 #define W_NOGLOB 0x20 /* Do not perform globbing on this word. */
68 /* Possible values for subshell_environment */
69 #define SUBSHELL_ASYNC 0x01 /* subshell caused by `command &' */
70 #define SUBSHELL_PAREN 0x02 /* subshell caused by ( ... ) */
71 #define SUBSHELL_COMSUB 0x04 /* subshell caused by `command` or $(command) */
72 #define SUBSHELL_FORK 0x08 /* subshell caused by executing a disk command */
74 /* A structure which represents a word. */
75 typedef struct word_desc {
76 char *word; /* Zero terminated string. */
77 int flags; /* Flags associated with this word. */
80 /* A linked list of words. */
81 typedef struct word_list {
82 struct word_list *next;
87 /* **************************************************************** */
89 /* Shell Command Structs */
91 /* **************************************************************** */
93 /* What a redirection descriptor looks like. If FLAGS is IS_DESCRIPTOR,
94 then we use REDIRECTEE.DEST, else we use the file specified. */
97 long dest; /* Place to redirect REDIRECTOR to, or ... */
98 WORD_DESC *filename; /* filename to redirect to. */
101 typedef struct redirect {
102 struct redirect *next; /* Next element, or NULL. */
103 int redirector; /* Descriptor to be redirected. */
104 int flags; /* Flag value for `open'. */
105 enum r_instruction instruction; /* What to do with the information. */
106 REDIRECTEE redirectee; /* File descriptor or filename */
107 char *here_doc_eof; /* The word that appeared in <<foo. */
110 /* An element used in parsing. A single word or a single redirection.
111 This is an ephemeral construct. */
112 typedef struct element {
117 /* Possible values for command->flags. */
118 #define CMD_WANT_SUBSHELL 0x01 /* User wants a subshell: ( command ) */
119 #define CMD_FORCE_SUBSHELL 0x02 /* Shell needs to force a subshell. */
120 #define CMD_INVERT_RETURN 0x04 /* Invert the exit value. */
121 #define CMD_IGNORE_RETURN 0x08 /* Ignore the exit value. For set -e. */
122 #define CMD_NO_FUNCTIONS 0x10 /* Ignore functions during command lookup. */
123 #define CMD_INHIBIT_EXPANSION 0x20 /* Do not expand the command words. */
124 #define CMD_NO_FORK 0x40 /* Don't fork; just call execve */
125 #define CMD_TIME_PIPELINE 0x80 /* Time a pipeline */
126 #define CMD_TIME_POSIX 0x100 /* time -p; use POSIX.2 time output spec. */
127 #define CMD_AMPERSAND 0x200 /* command & */
128 #define CMD_STDIN_REDIR 0x400 /* async command needs implicit </dev/null */
130 /* What a command looks like. */
131 typedef struct command {
132 enum command_type type; /* FOR CASE WHILE IF CONNECTION or SIMPLE. */
133 int flags; /* Flags controlling execution environment. */
134 int line; /* line number the command starts on */
135 REDIRECT *redirects; /* Special redirects for FOR CASE, etc. */
138 struct case_com *Case;
139 struct while_com *While;
141 struct connection *Connection;
142 struct simple_com *Simple;
143 struct function_def *Function_def;
144 struct group_com *Group;
145 #if defined (SELECT_COMMAND)
146 struct select_com *Select;
148 #if defined (DPAREN_ARITHMETIC)
149 struct arith_com *Arith;
151 #if defined (COND_COMMAND)
152 struct cond_com *Cond;
154 #if defined (ARITH_FOR_COMMAND)
155 struct arith_for_com *ArithFor;
157 struct subshell_com *Subshell;
161 /* Structure used to represent the CONNECTION type. */
162 typedef struct connection {
163 int ignore; /* Unused; simplifies make_command (). */
164 COMMAND *first; /* Pointer to the first command. */
165 COMMAND *second; /* Pointer to the second command. */
166 int connector; /* What separates this command from others. */
169 /* Structures used to represent the CASE command. */
171 /* Pattern/action structure for CASE_COM. */
172 typedef struct pattern_list {
173 struct pattern_list *next; /* Clause to try in case this one failed. */
174 WORD_LIST *patterns; /* Linked list of patterns to test. */
175 COMMAND *action; /* Thing to execute if a pattern matches. */
178 /* The CASE command. */
179 typedef struct case_com {
180 int flags; /* See description of CMD flags. */
181 WORD_DESC *word; /* The thing to test. */
182 PATTERN_LIST *clauses; /* The clauses to test against, or NULL. */
186 typedef struct for_com {
187 int flags; /* See description of CMD flags. */
188 WORD_DESC *name; /* The variable name to get mapped over. */
189 WORD_LIST *map_list; /* The things to map over. This is never NULL. */
190 COMMAND *action; /* The action to execute.
191 During execution, NAME is bound to successive
192 members of MAP_LIST. */
195 #if defined (ARITH_FOR_COMMAND)
196 typedef struct arith_for_com {
198 int line; /* generally used for error messages */
206 #if defined (SELECT_COMMAND)
207 /* KSH SELECT command. */
208 typedef struct select_com {
209 int flags; /* See description of CMD flags. */
210 WORD_DESC *name; /* The variable name to get mapped over. */
211 WORD_LIST *map_list; /* The things to map over. This is never NULL. */
212 COMMAND *action; /* The action to execute.
213 During execution, NAME is bound to the member of
214 MAP_LIST chosen by the user. */
216 #endif /* SELECT_COMMAND */
219 typedef struct if_com {
220 int flags; /* See description of CMD flags. */
221 COMMAND *test; /* Thing to test. */
222 COMMAND *true_case; /* What to do if the test returned non-zero. */
223 COMMAND *false_case; /* What to do if the test returned zero. */
227 typedef struct while_com {
228 int flags; /* See description of CMD flags. */
229 COMMAND *test; /* Thing to test. */
230 COMMAND *action; /* Thing to do while test is non-zero. */
233 #if defined (DPAREN_ARITHMETIC)
234 /* The arithmetic evaluation command, ((...)). Just a set of flags and
235 a WORD_LIST, of which the first element is the only one used, for the
237 typedef struct arith_com {
242 #endif /* DPAREN_ARITHMETIC */
244 /* The conditional command, [[...]]. This is a binary tree -- we slippped
245 a recursive-descent parser into the YACC grammar to parse it. */
249 #define COND_BINARY 4
253 typedef struct cond_com {
258 struct cond_com *left, *right;
261 /* The "simple" command. Just a collection of words and redirects. */
262 typedef struct simple_com {
263 int flags; /* See description of CMD flags. */
264 WORD_LIST *words; /* The program name, the arguments,
265 variable assignments, etc. */
266 REDIRECT *redirects; /* Redirections to perform. */
267 int line; /* line number the command starts on */
270 /* The "function definition" command. */
271 typedef struct function_def {
272 int flags; /* See description of CMD flags. */
273 WORD_DESC *name; /* The name of the function. */
274 COMMAND *command; /* The parsed execution tree. */
275 int line; /* Line number the function def starts on. */
278 /* A command that is `grouped' allows pipes and redirections to affect all
279 commands in the group. */
280 typedef struct group_com {
281 int ignore; /* See description of CMD flags. */
285 typedef struct subshell_com {
290 extern COMMAND *global_command;
292 /* Possible command errors */
293 #define CMDERR_DEFAULT 0
294 #define CMDERR_BADTYPE 1
295 #define CMDERR_BADCONN 2
296 #define CMDERR_BADJUMP 3
298 #define CMDERR_LAST 3
300 /* Forward declarations of functions declared in copy_cmd.c. */
302 extern WORD_DESC *copy_word __P((WORD_DESC *));
303 extern WORD_LIST *copy_word_list __P((WORD_LIST *));
304 extern REDIRECT *copy_redirect __P((REDIRECT *));
305 extern REDIRECT *copy_redirects __P((REDIRECT *));
306 extern COMMAND *copy_command __P((COMMAND *));
308 #endif /* _COMMAND_H_ */