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) 1993-2005 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 0x00001 /* Dollar sign present. */
71 #define W_QUOTED 0x00002 /* Some form of quote character is present. */
72 #define W_ASSIGNMENT 0x00004 /* This word is a variable assignment. */
73 #define W_GLOBEXP 0x00008 /* This word is the result of a glob expansion. */
74 #define W_NOSPLIT 0x00010 /* Do not perform word splitting on this word. */
75 #define W_NOGLOB 0x00020 /* Do not perform globbing on this word. */
76 #define W_NOSPLIT2 0x00040 /* Don't split word except for $@ expansion. */
77 #define W_TILDEEXP 0x00080 /* Tilde expand this assignment word */
78 #define W_DOLLARAT 0x00100 /* $@ and its special handling */
79 #define W_DOLLARSTAR 0x00200 /* $* and its special handling */
80 #define W_NOCOMSUB 0x00400 /* Don't perform command substitution on this word */
81 #define W_ASSIGNRHS 0x00800 /* Word is rhs of an assignment statement */
82 #define W_NOTILDE 0x01000 /* Don't perform tilde expansion on this word */
83 #define W_ITILDE 0x02000 /* Internal flag for word expansion */
84 #define W_NOEXPAND 0x04000 /* Don't expand at all -- do quote removal */
85 #define W_COMPASSIGN 0x08000 /* Compound assignment */
86 #define W_ASSNBLTIN 0x10000 /* word is a builtin command that takes assignments */
87 #define W_ASSIGNARG 0x20000 /* word is assignment argument to command */
88 #define W_HASQUOTEDNULL 0x40000 /* word contains a quoted null character */
89 #define W_DQUOTE 0x80000 /* word should be treated as if double-quoted */
91 /* Possible values for subshell_environment */
92 #define SUBSHELL_ASYNC 0x01 /* subshell caused by `command &' */
93 #define SUBSHELL_PAREN 0x02 /* subshell caused by ( ... ) */
94 #define SUBSHELL_COMSUB 0x04 /* subshell caused by `command` or $(command) */
95 #define SUBSHELL_FORK 0x08 /* subshell caused by executing a disk command */
96 #define SUBSHELL_PIPE 0x10 /* subshell from a pipeline element */
98 /* A structure which represents a word. */
99 typedef struct word_desc {
100 char *word; /* Zero terminated string. */
101 int flags; /* Flags associated with this word. */
104 /* A linked list of words. */
105 typedef struct word_list {
106 struct word_list *next;
111 /* **************************************************************** */
113 /* Shell Command Structs */
115 /* **************************************************************** */
117 /* What a redirection descriptor looks like. If the redirection instruction
118 is ri_duplicating_input or ri_duplicating_output, use DEST, otherwise
119 use the file in FILENAME. Out-of-range descriptors are identified by a
123 int dest; /* Place to redirect REDIRECTOR to, or ... */
124 WORD_DESC *filename; /* filename to redirect to. */
127 /* Structure describing a redirection. If REDIRECTOR is negative, the parser
128 (or translator in redir.c) encountered an out-of-range file descriptor. */
129 typedef struct redirect {
130 struct redirect *next; /* Next element, or NULL. */
131 int redirector; /* Descriptor to be redirected. */
132 int flags; /* Flag value for `open'. */
133 enum r_instruction instruction; /* What to do with the information. */
134 REDIRECTEE redirectee; /* File descriptor or filename */
135 char *here_doc_eof; /* The word that appeared in <<foo. */
138 /* An element used in parsing. A single word or a single redirection.
139 This is an ephemeral construct. */
140 typedef struct element {
145 /* Possible values for command->flags. */
146 #define CMD_WANT_SUBSHELL 0x01 /* User wants a subshell: ( command ) */
147 #define CMD_FORCE_SUBSHELL 0x02 /* Shell needs to force a subshell. */
148 #define CMD_INVERT_RETURN 0x04 /* Invert the exit value. */
149 #define CMD_IGNORE_RETURN 0x08 /* Ignore the exit value. For set -e. */
150 #define CMD_NO_FUNCTIONS 0x10 /* Ignore functions during command lookup. */
151 #define CMD_INHIBIT_EXPANSION 0x20 /* Do not expand the command words. */
152 #define CMD_NO_FORK 0x40 /* Don't fork; just call execve */
153 #define CMD_TIME_PIPELINE 0x80 /* Time a pipeline */
154 #define CMD_TIME_POSIX 0x100 /* time -p; use POSIX.2 time output spec. */
155 #define CMD_AMPERSAND 0x200 /* command & */
156 #define CMD_STDIN_REDIR 0x400 /* async command needs implicit </dev/null */
157 #define CMD_COMMAND_BUILTIN 0x0800 /* command executed by `command' builtin */
159 /* What a command looks like. */
160 typedef struct command {
161 enum command_type type; /* FOR CASE WHILE IF CONNECTION or SIMPLE. */
162 int flags; /* Flags controlling execution environment. */
163 int line; /* line number the command starts on */
164 REDIRECT *redirects; /* Special redirects for FOR CASE, etc. */
167 struct case_com *Case;
168 struct while_com *While;
170 struct connection *Connection;
171 struct simple_com *Simple;
172 struct function_def *Function_def;
173 struct group_com *Group;
174 #if defined (SELECT_COMMAND)
175 struct select_com *Select;
177 #if defined (DPAREN_ARITHMETIC)
178 struct arith_com *Arith;
180 #if defined (COND_COMMAND)
181 struct cond_com *Cond;
183 #if defined (ARITH_FOR_COMMAND)
184 struct arith_for_com *ArithFor;
186 struct subshell_com *Subshell;
190 /* Structure used to represent the CONNECTION type. */
191 typedef struct connection {
192 int ignore; /* Unused; simplifies make_command (). */
193 COMMAND *first; /* Pointer to the first command. */
194 COMMAND *second; /* Pointer to the second command. */
195 int connector; /* What separates this command from others. */
198 /* Structures used to represent the CASE command. */
200 /* Pattern/action structure for CASE_COM. */
201 typedef struct pattern_list {
203 struct pattern_list *next; /* Clause to try in case this one failed. */
204 WORD_LIST *patterns; /* Linked list of patterns to test. */
205 COMMAND *action; /* Thing to execute if a pattern matches. */
208 /* The CASE command. */
209 typedef struct case_com {
210 int flags; /* See description of CMD flags. */
211 int line; /* line number the `case' keyword appears on */
212 WORD_DESC *word; /* The thing to test. */
213 PATTERN_LIST *clauses; /* The clauses to test against, or NULL. */
217 typedef struct for_com {
218 int flags; /* See description of CMD flags. */
219 int line; /* line number the `for' keyword appears on */
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 successive
224 members of MAP_LIST. */
227 #if defined (ARITH_FOR_COMMAND)
228 typedef struct arith_for_com {
230 int line; /* generally used for error messages */
238 #if defined (SELECT_COMMAND)
239 /* KSH SELECT command. */
240 typedef struct select_com {
241 int flags; /* See description of CMD flags. */
242 int line; /* line number the `select' keyword appears on */
243 WORD_DESC *name; /* The variable name to get mapped over. */
244 WORD_LIST *map_list; /* The things to map over. This is never NULL. */
245 COMMAND *action; /* The action to execute.
246 During execution, NAME is bound to the member of
247 MAP_LIST chosen by the user. */
249 #endif /* SELECT_COMMAND */
252 typedef struct if_com {
253 int flags; /* See description of CMD flags. */
254 COMMAND *test; /* Thing to test. */
255 COMMAND *true_case; /* What to do if the test returned non-zero. */
256 COMMAND *false_case; /* What to do if the test returned zero. */
260 typedef struct while_com {
261 int flags; /* See description of CMD flags. */
262 COMMAND *test; /* Thing to test. */
263 COMMAND *action; /* Thing to do while test is non-zero. */
266 #if defined (DPAREN_ARITHMETIC)
267 /* The arithmetic evaluation command, ((...)). Just a set of flags and
268 a WORD_LIST, of which the first element is the only one used, for the
270 typedef struct arith_com {
275 #endif /* DPAREN_ARITHMETIC */
277 /* The conditional command, [[...]]. This is a binary tree -- we slippped
278 a recursive-descent parser into the YACC grammar to parse it. */
282 #define COND_BINARY 4
286 typedef struct cond_com {
291 struct cond_com *left, *right;
294 /* The "simple" command. Just a collection of words and redirects. */
295 typedef struct simple_com {
296 int flags; /* See description of CMD flags. */
297 int line; /* line number the command starts on */
298 WORD_LIST *words; /* The program name, the arguments,
299 variable assignments, etc. */
300 REDIRECT *redirects; /* Redirections to perform. */
303 /* The "function definition" command. */
304 typedef struct function_def {
305 int flags; /* See description of CMD flags. */
306 int line; /* Line number the function def starts on. */
307 WORD_DESC *name; /* The name of the function. */
308 COMMAND *command; /* The parsed execution tree. */
309 char *source_file; /* file in which function was defined, if any */
312 /* A command that is `grouped' allows pipes and redirections to affect all
313 commands in the group. */
314 typedef struct group_com {
315 int ignore; /* See description of CMD flags. */
319 typedef struct subshell_com {
324 extern COMMAND *global_command;
326 /* Possible command errors */
327 #define CMDERR_DEFAULT 0
328 #define CMDERR_BADTYPE 1
329 #define CMDERR_BADCONN 2
330 #define CMDERR_BADJUMP 3
332 #define CMDERR_LAST 3
334 /* Forward declarations of functions declared in copy_cmd.c. */
336 extern FUNCTION_DEF *copy_function_def_contents __P((FUNCTION_DEF *, FUNCTION_DEF *));
337 extern FUNCTION_DEF *copy_function_def __P((FUNCTION_DEF *));
339 extern WORD_DESC *copy_word __P((WORD_DESC *));
340 extern WORD_LIST *copy_word_list __P((WORD_LIST *));
341 extern REDIRECT *copy_redirect __P((REDIRECT *));
342 extern REDIRECT *copy_redirects __P((REDIRECT *));
343 extern COMMAND *copy_command __P((COMMAND *));
345 #endif /* _COMMAND_H_ */