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_reading_string,
31 r_duplicating_input, r_duplicating_output, r_deblank_reading_until,
32 r_close_this, r_err_and_out, r_input_output, r_output_force,
33 r_duplicating_input_word, r_duplicating_output_word,
34 r_move_input, r_move_output, r_move_input_word, r_move_output_word
37 /* Redirection errors. */
38 #define AMBIGUOUS_REDIRECT -1
39 #define NOCLOBBER_REDIRECT -2
40 #define RESTRICTED_REDIRECT -3 /* can only happen in restricted shells. */
41 #define HEREDOC_REDIRECT -4 /* here-doc temp file can't be created */
43 #define CLOBBERING_REDIRECT(ri) \
44 (ri == r_output_direction || ri == r_err_and_out)
46 #define OUTPUT_REDIRECT(ri) \
47 (ri == r_output_direction || ri == r_input_output || ri == r_err_and_out)
49 #define INPUT_REDIRECT(ri) \
50 (ri == r_input_direction || ri == r_inputa_direction || ri == r_input_output)
52 #define WRITE_REDIRECT(ri) \
53 (ri == r_output_direction || \
54 ri == r_input_output || \
55 ri == r_err_and_out || \
56 ri == r_appending_to || \
59 /* redirection needs translation */
60 #define TRANSLATE_REDIRECT(ri) \
61 (ri == r_duplicating_input_word || ri == r_duplicating_output_word || \
62 ri == r_move_input_word || ri == r_move_output_word)
65 enum command_type { cm_for, cm_case, cm_while, cm_if, cm_simple, cm_select,
66 cm_connection, cm_function_def, cm_until, cm_group,
67 cm_arith, cm_cond, cm_arith_for, cm_subshell };
69 /* Possible values for the `flags' field of a WORD_DESC. */
70 #define W_HASDOLLAR 0x01 /* Dollar sign present. */
71 #define W_QUOTED 0x02 /* Some form of quote character is present. */
72 #define W_ASSIGNMENT 0x04 /* This word is a variable assignment. */
73 #define W_GLOBEXP 0x08 /* This word is the result of a glob expansion. */
74 #define W_NOSPLIT 0x10 /* Do not perform word splitting on this word. */
75 #define W_NOGLOB 0x20 /* Do not perform globbing on this word. */
76 #define W_NOSPLIT2 0x40 /* Don't split word except for $@ expansion. */
77 #define W_TILDEEXP 0x80 /* Tilde expand this assignment word */
79 /* Possible values for subshell_environment */
80 #define SUBSHELL_ASYNC 0x01 /* subshell caused by `command &' */
81 #define SUBSHELL_PAREN 0x02 /* subshell caused by ( ... ) */
82 #define SUBSHELL_COMSUB 0x04 /* subshell caused by `command` or $(command) */
83 #define SUBSHELL_FORK 0x08 /* subshell caused by executing a disk command */
84 #define SUBSHELL_PIPE 0x10 /* subshell from a pipeline element */
86 /* A structure which represents a word. */
87 typedef struct word_desc {
88 char *word; /* Zero terminated string. */
89 int flags; /* Flags associated with this word. */
92 /* A linked list of words. */
93 typedef struct word_list {
94 struct word_list *next;
99 /* **************************************************************** */
101 /* Shell Command Structs */
103 /* **************************************************************** */
105 /* What a redirection descriptor looks like. If the redirection instruction
106 is ri_duplicating_input or ri_duplicating_output, use DEST, otherwise
107 use the file in FILENAME. Out-of-range descriptors are identified by a
111 int dest; /* Place to redirect REDIRECTOR to, or ... */
112 WORD_DESC *filename; /* filename to redirect to. */
115 /* Structure describing a redirection. If REDIRECTOR is negative, the parser
116 (or translator in redir.c) encountered an out-of-range file descriptor. */
117 typedef struct redirect {
118 struct redirect *next; /* Next element, or NULL. */
119 int redirector; /* Descriptor to be redirected. */
120 int flags; /* Flag value for `open'. */
121 enum r_instruction instruction; /* What to do with the information. */
122 REDIRECTEE redirectee; /* File descriptor or filename */
123 char *here_doc_eof; /* The word that appeared in <<foo. */
126 /* An element used in parsing. A single word or a single redirection.
127 This is an ephemeral construct. */
128 typedef struct element {
133 /* Possible values for command->flags. */
134 #define CMD_WANT_SUBSHELL 0x01 /* User wants a subshell: ( command ) */
135 #define CMD_FORCE_SUBSHELL 0x02 /* Shell needs to force a subshell. */
136 #define CMD_INVERT_RETURN 0x04 /* Invert the exit value. */
137 #define CMD_IGNORE_RETURN 0x08 /* Ignore the exit value. For set -e. */
138 #define CMD_NO_FUNCTIONS 0x10 /* Ignore functions during command lookup. */
139 #define CMD_INHIBIT_EXPANSION 0x20 /* Do not expand the command words. */
140 #define CMD_NO_FORK 0x40 /* Don't fork; just call execve */
141 #define CMD_TIME_PIPELINE 0x80 /* Time a pipeline */
142 #define CMD_TIME_POSIX 0x100 /* time -p; use POSIX.2 time output spec. */
143 #define CMD_AMPERSAND 0x200 /* command & */
144 #define CMD_STDIN_REDIR 0x400 /* async command needs implicit </dev/null */
145 #define CMD_COMMAND_BUILTIN 0x0800 /* command executed by `command' builtin */
147 /* What a command looks like. */
148 typedef struct command {
149 enum command_type type; /* FOR CASE WHILE IF CONNECTION or SIMPLE. */
150 int flags; /* Flags controlling execution environment. */
151 int line; /* line number the command starts on */
152 REDIRECT *redirects; /* Special redirects for FOR CASE, etc. */
155 struct case_com *Case;
156 struct while_com *While;
158 struct connection *Connection;
159 struct simple_com *Simple;
160 struct function_def *Function_def;
161 struct group_com *Group;
162 #if defined (SELECT_COMMAND)
163 struct select_com *Select;
165 #if defined (DPAREN_ARITHMETIC)
166 struct arith_com *Arith;
168 #if defined (COND_COMMAND)
169 struct cond_com *Cond;
171 #if defined (ARITH_FOR_COMMAND)
172 struct arith_for_com *ArithFor;
174 struct subshell_com *Subshell;
178 /* Structure used to represent the CONNECTION type. */
179 typedef struct connection {
180 int ignore; /* Unused; simplifies make_command (). */
181 COMMAND *first; /* Pointer to the first command. */
182 COMMAND *second; /* Pointer to the second command. */
183 int connector; /* What separates this command from others. */
186 /* Structures used to represent the CASE command. */
188 /* Pattern/action structure for CASE_COM. */
189 typedef struct pattern_list {
190 struct pattern_list *next; /* Clause to try in case this one failed. */
191 WORD_LIST *patterns; /* Linked list of patterns to test. */
192 COMMAND *action; /* Thing to execute if a pattern matches. */
195 /* The CASE command. */
196 typedef struct case_com {
197 int flags; /* See description of CMD flags. */
198 WORD_DESC *word; /* The thing to test. */
199 PATTERN_LIST *clauses; /* The clauses to test against, or NULL. */
203 typedef struct for_com {
204 int flags; /* See description of CMD flags. */
205 WORD_DESC *name; /* The variable name to get mapped over. */
206 WORD_LIST *map_list; /* The things to map over. This is never NULL. */
207 COMMAND *action; /* The action to execute.
208 During execution, NAME is bound to successive
209 members of MAP_LIST. */
212 #if defined (ARITH_FOR_COMMAND)
213 typedef struct arith_for_com {
215 int line; /* generally used for error messages */
223 #if defined (SELECT_COMMAND)
224 /* KSH SELECT command. */
225 typedef struct select_com {
226 int flags; /* See description of CMD flags. */
227 WORD_DESC *name; /* The variable name to get mapped over. */
228 WORD_LIST *map_list; /* The things to map over. This is never NULL. */
229 COMMAND *action; /* The action to execute.
230 During execution, NAME is bound to the member of
231 MAP_LIST chosen by the user. */
233 #endif /* SELECT_COMMAND */
236 typedef struct if_com {
237 int flags; /* See description of CMD flags. */
238 COMMAND *test; /* Thing to test. */
239 COMMAND *true_case; /* What to do if the test returned non-zero. */
240 COMMAND *false_case; /* What to do if the test returned zero. */
244 typedef struct while_com {
245 int flags; /* See description of CMD flags. */
246 COMMAND *test; /* Thing to test. */
247 COMMAND *action; /* Thing to do while test is non-zero. */
250 #if defined (DPAREN_ARITHMETIC)
251 /* The arithmetic evaluation command, ((...)). Just a set of flags and
252 a WORD_LIST, of which the first element is the only one used, for the
254 typedef struct arith_com {
259 #endif /* DPAREN_ARITHMETIC */
261 /* The conditional command, [[...]]. This is a binary tree -- we slippped
262 a recursive-descent parser into the YACC grammar to parse it. */
266 #define COND_BINARY 4
270 typedef struct cond_com {
275 struct cond_com *left, *right;
278 /* The "simple" command. Just a collection of words and redirects. */
279 typedef struct simple_com {
280 int flags; /* See description of CMD flags. */
281 WORD_LIST *words; /* The program name, the arguments,
282 variable assignments, etc. */
283 REDIRECT *redirects; /* Redirections to perform. */
284 int line; /* line number the command starts on */
287 /* The "function definition" command. */
288 typedef struct function_def {
289 int flags; /* See description of CMD flags. */
290 WORD_DESC *name; /* The name of the function. */
291 COMMAND *command; /* The parsed execution tree. */
292 int line; /* Line number the function def starts on. */
295 /* A command that is `grouped' allows pipes and redirections to affect all
296 commands in the group. */
297 typedef struct group_com {
298 int ignore; /* See description of CMD flags. */
302 typedef struct subshell_com {
307 extern COMMAND *global_command;
309 /* Possible command errors */
310 #define CMDERR_DEFAULT 0
311 #define CMDERR_BADTYPE 1
312 #define CMDERR_BADCONN 2
313 #define CMDERR_BADJUMP 3
315 #define CMDERR_LAST 3
317 /* Forward declarations of functions declared in copy_cmd.c. */
319 extern WORD_DESC *copy_word __P((WORD_DESC *));
320 extern WORD_LIST *copy_word_list __P((WORD_LIST *));
321 extern REDIRECT *copy_redirect __P((REDIRECT *));
322 extern REDIRECT *copy_redirects __P((REDIRECT *));
323 extern COMMAND *copy_command __P((COMMAND *));
325 #endif /* _COMMAND_H_ */