source: vendor/bash/3.1-p17/command.h@ 3854

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1/* command.h -- The structures used internally to represent commands, and
2 the extern declarations of the functions used to create them. */
3
4/* Copyright (C) 1993-2005 Free Software Foundation, Inc.
5
6 This file is part of GNU Bash, the Bourne Again SHell.
7
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
11 version.
12
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
16 for more details.
17
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. */
21
22#if !defined (_COMMAND_H_)
23#define _COMMAND_H_
24
25#include "stdc.h"
26
27/* Instructions describing what kind of thing to do for a redirection. */
28enum r_instruction {
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
35};
36
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 */
42
43#define CLOBBERING_REDIRECT(ri) \
44 (ri == r_output_direction || ri == r_err_and_out)
45
46#define OUTPUT_REDIRECT(ri) \
47 (ri == r_output_direction || ri == r_input_output || ri == r_err_and_out)
48
49#define INPUT_REDIRECT(ri) \
50 (ri == r_input_direction || ri == r_inputa_direction || ri == r_input_output)
51
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 || \
57 ri == r_output_force)
58
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)
63
64/* Command Types: */
65enum 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 };
68
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 */
90
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 */
97
98/* A structure which represents a word. */
99typedef struct word_desc {
100 char *word; /* Zero terminated string. */
101 int flags; /* Flags associated with this word. */
102} WORD_DESC;
103
104/* A linked list of words. */
105typedef struct word_list {
106 struct word_list *next;
107 WORD_DESC *word;
108} WORD_LIST;
109
110
111/* **************************************************************** */
112/* */
113/* Shell Command Structs */
114/* */
115/* **************************************************************** */
116
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
120 negative DEST. */
121
122typedef union {
123 int dest; /* Place to redirect REDIRECTOR to, or ... */
124 WORD_DESC *filename; /* filename to redirect to. */
125} REDIRECTEE;
126
127/* Structure describing a redirection. If REDIRECTOR is negative, the parser
128 (or translator in redir.c) encountered an out-of-range file descriptor. */
129typedef 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. */
136} REDIRECT;
137
138/* An element used in parsing. A single word or a single redirection.
139 This is an ephemeral construct. */
140typedef struct element {
141 WORD_DESC *word;
142 REDIRECT *redirect;
143} ELEMENT;
144
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 */
158
159/* What a command looks like. */
160typedef 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. */
165 union {
166 struct for_com *For;
167 struct case_com *Case;
168 struct while_com *While;
169 struct if_com *If;
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;
176#endif
177#if defined (DPAREN_ARITHMETIC)
178 struct arith_com *Arith;
179#endif
180#if defined (COND_COMMAND)
181 struct cond_com *Cond;
182#endif
183#if defined (ARITH_FOR_COMMAND)
184 struct arith_for_com *ArithFor;
185#endif
186 struct subshell_com *Subshell;
187 } value;
188} COMMAND;
189
190/* Structure used to represent the CONNECTION type. */
191typedef 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. */
196} CONNECTION;
197
198/* Structures used to represent the CASE command. */
199
200/* Pattern/action structure for CASE_COM. */
201typedef struct pattern_list {
202 struct pattern_list *next; /* Clause to try in case this one failed. */
203 WORD_LIST *patterns; /* Linked list of patterns to test. */
204 COMMAND *action; /* Thing to execute if a pattern matches. */
205 int flags;
206} PATTERN_LIST;
207
208/* The CASE command. */
209typedef 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. */
214} CASE_COM;
215
216/* FOR command. */
217typedef 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. */
225} FOR_COM;
226
227#if defined (ARITH_FOR_COMMAND)
228typedef struct arith_for_com {
229 int flags;
230 int line; /* generally used for error messages */
231 WORD_LIST *init;
232 WORD_LIST *test;
233 WORD_LIST *step;
234 COMMAND *action;
235} ARITH_FOR_COM;
236#endif
237
238#if defined (SELECT_COMMAND)
239/* KSH SELECT command. */
240typedef 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. */
248} SELECT_COM;
249#endif /* SELECT_COMMAND */
250
251/* IF command. */
252typedef 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. */
257} IF_COM;
258
259/* WHILE command. */
260typedef 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. */
264} WHILE_COM;
265
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
269 time being. */
270typedef struct arith_com {
271 int flags;
272 int line;
273 WORD_LIST *exp;
274} ARITH_COM;
275#endif /* DPAREN_ARITHMETIC */
276
277/* The conditional command, [[...]]. This is a binary tree -- we slippped
278 a recursive-descent parser into the YACC grammar to parse it. */
279#define COND_AND 1
280#define COND_OR 2
281#define COND_UNARY 3
282#define COND_BINARY 4
283#define COND_TERM 5
284#define COND_EXPR 6
285
286typedef struct cond_com {
287 int flags;
288 int line;
289 int type;
290 WORD_DESC *op;
291 struct cond_com *left, *right;
292} COND_COM;
293
294/* The "simple" command. Just a collection of words and redirects. */
295typedef 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. */
301} SIMPLE_COM;
302
303/* The "function definition" command. */
304typedef 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 */
310} FUNCTION_DEF;
311
312/* A command that is `grouped' allows pipes and redirections to affect all
313 commands in the group. */
314typedef struct group_com {
315 int ignore; /* See description of CMD flags. */
316 COMMAND *command;
317} GROUP_COM;
318
319typedef struct subshell_com {
320 int flags;
321 COMMAND *command;
322} SUBSHELL_COM;
323
324extern COMMAND *global_command;
325
326/* Possible command errors */
327#define CMDERR_DEFAULT 0
328#define CMDERR_BADTYPE 1
329#define CMDERR_BADCONN 2
330#define CMDERR_BADJUMP 3
331
332#define CMDERR_LAST 3
333
334/* Forward declarations of functions declared in copy_cmd.c. */
335
336extern FUNCTION_DEF *copy_function_def_contents __P((FUNCTION_DEF *, FUNCTION_DEF *));
337extern FUNCTION_DEF *copy_function_def __P((FUNCTION_DEF *));
338
339extern WORD_DESC *copy_word __P((WORD_DESC *));
340extern WORD_LIST *copy_word_list __P((WORD_LIST *));
341extern REDIRECT *copy_redirect __P((REDIRECT *));
342extern REDIRECT *copy_redirects __P((REDIRECT *));
343extern COMMAND *copy_command __P((COMMAND *));
344
345#endif /* _COMMAND_H_ */
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