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 CLOBBERING_REDIRECT(ri) \
43 (ri == r_output_direction || ri == r_err_and_out)
45 #define OUTPUT_REDIRECT(ri) \
46 (ri == r_output_direction || ri == r_input_output || ri == r_err_and_out)
48 #define INPUT_REDIRECT(ri) \
49 (ri == r_input_direction || ri == r_inputa_direction || ri == r_input_output)
51 #define WRITE_REDIRECT(ri) \
52 (ri == r_output_direction || \
53 ri == r_input_output || \
54 ri == r_err_and_out || \
55 ri == r_appending_to || \
59 enum command_type { cm_for, cm_case, cm_while, cm_if, cm_simple, cm_select,
60 cm_connection, cm_function_def, cm_until, cm_group,
61 cm_arith, cm_cond, cm_arith_for, cm_subshell };
63 /* Possible values for the `flags' field of a WORD_DESC. */
64 #define W_HASDOLLAR 0x01 /* Dollar sign present. */
65 #define W_QUOTED 0x02 /* Some form of quote character is present. */
66 #define W_ASSIGNMENT 0x04 /* This word is a variable assignment. */
67 #define W_GLOBEXP 0x08 /* This word is the result of a glob expansion. */
68 #define W_NOSPLIT 0x10 /* Do not perform word splitting on this word. */
69 #define W_NOGLOB 0x20 /* Do not perform globbing on this word. */
70 #define W_NOSPLIT2 0x40 /* Don't split word except for $@ expansion. */
72 /* Possible values for subshell_environment */
73 #define SUBSHELL_ASYNC 0x01 /* subshell caused by `command &' */
74 #define SUBSHELL_PAREN 0x02 /* subshell caused by ( ... ) */
75 #define SUBSHELL_COMSUB 0x04 /* subshell caused by `command` or $(command) */
76 #define SUBSHELL_FORK 0x08 /* subshell caused by executing a disk command */
77 #define SUBSHELL_PIPE 0x10 /* subshell from a pipeline element */
79 /* A structure which represents a word. */
80 typedef struct word_desc {
81 char *word; /* Zero terminated string. */
82 int flags; /* Flags associated with this word. */
85 /* A linked list of words. */
86 typedef struct word_list {
87 struct word_list *next;
92 /* **************************************************************** */
94 /* Shell Command Structs */
96 /* **************************************************************** */
98 /* What a redirection descriptor looks like. If the redirection instruction
99 is ri_duplicating_input or ri_duplicating_output, use DEST, otherwise
100 use the file in FILENAME. Out-of-range descriptors are identified by a
104 int dest; /* Place to redirect REDIRECTOR to, or ... */
105 WORD_DESC *filename; /* filename to redirect to. */
108 /* Structure describing a redirection. If REDIRECTOR is negative, the parser
109 (or translator in redir.c) encountered an out-of-range file descriptor. */
110 typedef struct redirect {
111 struct redirect *next; /* Next element, or NULL. */
112 int redirector; /* Descriptor to be redirected. */
113 int flags; /* Flag value for `open'. */
114 enum r_instruction instruction; /* What to do with the information. */
115 REDIRECTEE redirectee; /* File descriptor or filename */
116 char *here_doc_eof; /* The word that appeared in <<foo. */
119 /* An element used in parsing. A single word or a single redirection.
120 This is an ephemeral construct. */
121 typedef struct element {
126 /* Possible values for command->flags. */
127 #define CMD_WANT_SUBSHELL 0x01 /* User wants a subshell: ( command ) */
128 #define CMD_FORCE_SUBSHELL 0x02 /* Shell needs to force a subshell. */
129 #define CMD_INVERT_RETURN 0x04 /* Invert the exit value. */
130 #define CMD_IGNORE_RETURN 0x08 /* Ignore the exit value. For set -e. */
131 #define CMD_NO_FUNCTIONS 0x10 /* Ignore functions during command lookup. */
132 #define CMD_INHIBIT_EXPANSION 0x20 /* Do not expand the command words. */
133 #define CMD_NO_FORK 0x40 /* Don't fork; just call execve */
134 #define CMD_TIME_PIPELINE 0x80 /* Time a pipeline */
135 #define CMD_TIME_POSIX 0x100 /* time -p; use POSIX.2 time output spec. */
136 #define CMD_AMPERSAND 0x200 /* command & */
137 #define CMD_STDIN_REDIR 0x400 /* async command needs implicit </dev/null */
138 #define CMD_COMMAND_BUILTIN 0x0800 /* command executed by `command' builtin */
140 /* What a command looks like. */
141 typedef struct command {
142 enum command_type type; /* FOR CASE WHILE IF CONNECTION or SIMPLE. */
143 int flags; /* Flags controlling execution environment. */
144 int line; /* line number the command starts on */
145 REDIRECT *redirects; /* Special redirects for FOR CASE, etc. */
148 struct case_com *Case;
149 struct while_com *While;
151 struct connection *Connection;
152 struct simple_com *Simple;
153 struct function_def *Function_def;
154 struct group_com *Group;
155 #if defined (SELECT_COMMAND)
156 struct select_com *Select;
158 #if defined (DPAREN_ARITHMETIC)
159 struct arith_com *Arith;
161 #if defined (COND_COMMAND)
162 struct cond_com *Cond;
164 #if defined (ARITH_FOR_COMMAND)
165 struct arith_for_com *ArithFor;
167 struct subshell_com *Subshell;
171 /* Structure used to represent the CONNECTION type. */
172 typedef struct connection {
173 int ignore; /* Unused; simplifies make_command (). */
174 COMMAND *first; /* Pointer to the first command. */
175 COMMAND *second; /* Pointer to the second command. */
176 int connector; /* What separates this command from others. */
179 /* Structures used to represent the CASE command. */
181 /* Pattern/action structure for CASE_COM. */
182 typedef struct pattern_list {
183 struct pattern_list *next; /* Clause to try in case this one failed. */
184 WORD_LIST *patterns; /* Linked list of patterns to test. */
185 COMMAND *action; /* Thing to execute if a pattern matches. */
188 /* The CASE command. */
189 typedef struct case_com {
190 int flags; /* See description of CMD flags. */
191 WORD_DESC *word; /* The thing to test. */
192 PATTERN_LIST *clauses; /* The clauses to test against, or NULL. */
196 typedef struct for_com {
197 int flags; /* See description of CMD flags. */
198 WORD_DESC *name; /* The variable name to get mapped over. */
199 WORD_LIST *map_list; /* The things to map over. This is never NULL. */
200 COMMAND *action; /* The action to execute.
201 During execution, NAME is bound to successive
202 members of MAP_LIST. */
205 #if defined (ARITH_FOR_COMMAND)
206 typedef struct arith_for_com {
208 int line; /* generally used for error messages */
216 #if defined (SELECT_COMMAND)
217 /* KSH SELECT command. */
218 typedef struct select_com {
219 int flags; /* See description of CMD flags. */
220 WORD_DESC *name; /* The variable name to get mapped over. */
221 WORD_LIST *map_list; /* The things to map over. This is never NULL. */
222 COMMAND *action; /* The action to execute.
223 During execution, NAME is bound to the member of
224 MAP_LIST chosen by the user. */
226 #endif /* SELECT_COMMAND */
229 typedef struct if_com {
230 int flags; /* See description of CMD flags. */
231 COMMAND *test; /* Thing to test. */
232 COMMAND *true_case; /* What to do if the test returned non-zero. */
233 COMMAND *false_case; /* What to do if the test returned zero. */
237 typedef struct while_com {
238 int flags; /* See description of CMD flags. */
239 COMMAND *test; /* Thing to test. */
240 COMMAND *action; /* Thing to do while test is non-zero. */
243 #if defined (DPAREN_ARITHMETIC)
244 /* The arithmetic evaluation command, ((...)). Just a set of flags and
245 a WORD_LIST, of which the first element is the only one used, for the
247 typedef struct arith_com {
252 #endif /* DPAREN_ARITHMETIC */
254 /* The conditional command, [[...]]. This is a binary tree -- we slippped
255 a recursive-descent parser into the YACC grammar to parse it. */
259 #define COND_BINARY 4
263 typedef struct cond_com {
268 struct cond_com *left, *right;
271 /* The "simple" command. Just a collection of words and redirects. */
272 typedef struct simple_com {
273 int flags; /* See description of CMD flags. */
274 WORD_LIST *words; /* The program name, the arguments,
275 variable assignments, etc. */
276 REDIRECT *redirects; /* Redirections to perform. */
277 int line; /* line number the command starts on */
280 /* The "function definition" command. */
281 typedef struct function_def {
282 int flags; /* See description of CMD flags. */
283 WORD_DESC *name; /* The name of the function. */
284 COMMAND *command; /* The parsed execution tree. */
285 int line; /* Line number the function def starts on. */
288 /* A command that is `grouped' allows pipes and redirections to affect all
289 commands in the group. */
290 typedef struct group_com {
291 int ignore; /* See description of CMD flags. */
295 typedef struct subshell_com {
300 extern COMMAND *global_command;
302 /* Possible command errors */
303 #define CMDERR_DEFAULT 0
304 #define CMDERR_BADTYPE 1
305 #define CMDERR_BADCONN 2
306 #define CMDERR_BADJUMP 3
308 #define CMDERR_LAST 3
310 /* Forward declarations of functions declared in copy_cmd.c. */
312 extern WORD_DESC *copy_word __P((WORD_DESC *));
313 extern WORD_LIST *copy_word_list __P((WORD_LIST *));
314 extern REDIRECT *copy_redirect __P((REDIRECT *));
315 extern REDIRECT *copy_redirects __P((REDIRECT *));
316 extern COMMAND *copy_command __P((COMMAND *));
318 #endif /* _COMMAND_H_ */