Jari Aalto | 726f638 | 1996-08-26 18:22:31 +0000 | [diff] [blame^] | 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 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, 675 Mass Ave, Cambridge, MA 02139, 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. */ |
| 28 | enum r_instruction { |
| 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 |
| 34 | }; |
| 35 | |
| 36 | /* Command Types: */ |
| 37 | enum command_type { cm_for, cm_case, cm_while, cm_if, cm_simple, cm_select, |
| 38 | cm_connection, cm_function_def, cm_until, cm_group }; |
| 39 | |
| 40 | /* A structure which represents a word. */ |
| 41 | typedef struct word_desc { |
| 42 | char *word; /* Zero terminated string. */ |
| 43 | int dollar_present; /* Non-zero means dollar sign present. */ |
| 44 | int quoted; /* Non-zero means single, double, or back quote |
| 45 | or backslash is present. */ |
| 46 | int assignment; /* Non-zero means that this word contains an |
| 47 | assignment. */ |
| 48 | } WORD_DESC; |
| 49 | |
| 50 | /* A linked list of words. */ |
| 51 | typedef struct word_list { |
| 52 | struct word_list *next; |
| 53 | WORD_DESC *word; |
| 54 | } WORD_LIST; |
| 55 | |
| 56 | |
| 57 | /* **************************************************************** */ |
| 58 | /* */ |
| 59 | /* Shell Command Structs */ |
| 60 | /* */ |
| 61 | /* **************************************************************** */ |
| 62 | |
| 63 | /* What a redirection descriptor looks like. If FLAGS is IS_DESCRIPTOR, |
| 64 | then we use REDIRECTEE.DEST, else we use the file specified. */ |
| 65 | |
| 66 | typedef union { |
| 67 | long dest; /* Place to redirect REDIRECTOR to, or ... */ |
| 68 | WORD_DESC *filename; /* filename to redirect to. */ |
| 69 | } REDIRECTEE; |
| 70 | |
| 71 | typedef struct redirect { |
| 72 | struct redirect *next; /* Next element, or NULL. */ |
| 73 | int redirector; /* Descriptor to be redirected. */ |
| 74 | int flags; /* Flag value for `open'. */ |
| 75 | enum r_instruction instruction; /* What to do with the information. */ |
| 76 | REDIRECTEE redirectee; /* File descriptor or filename */ |
| 77 | char *here_doc_eof; /* The word that appeared in <<foo. */ |
| 78 | } REDIRECT; |
| 79 | |
| 80 | /* An element used in parsing. A single word or a single redirection. |
| 81 | This is an ephemeral construct. */ |
| 82 | typedef struct element { |
| 83 | WORD_DESC *word; |
| 84 | REDIRECT *redirect; |
| 85 | } ELEMENT; |
| 86 | |
| 87 | /* Possible values for command->flags. */ |
| 88 | #define CMD_WANT_SUBSHELL 0x01 /* User wants a subshell: ( command ) */ |
| 89 | #define CMD_FORCE_SUBSHELL 0x02 /* Shell needs to force a subshell. */ |
| 90 | #define CMD_INVERT_RETURN 0x04 /* Invert the exit value. */ |
| 91 | #define CMD_IGNORE_RETURN 0x08 /* Ignore the exit value. For set -e. */ |
| 92 | #define CMD_NO_FUNCTIONS 0x10 /* Ignore functions during command lookup. */ |
| 93 | #define CMD_INHIBIT_EXPANSION 0x20 /* Do not expand the command words. */ |
| 94 | #define CMD_NO_FORK 0x40 /* Don't fork; just call execve */ |
| 95 | |
| 96 | /* What a command looks like. */ |
| 97 | typedef struct command { |
| 98 | enum command_type type; /* FOR CASE WHILE IF CONNECTION or SIMPLE. */ |
| 99 | int flags; /* Flags controlling execution environment. */ |
| 100 | int line; /* line number the command starts on */ |
| 101 | REDIRECT *redirects; /* Special redirects for FOR CASE, etc. */ |
| 102 | union { |
| 103 | struct for_com *For; |
| 104 | struct case_com *Case; |
| 105 | struct while_com *While; |
| 106 | struct if_com *If; |
| 107 | struct connection *Connection; |
| 108 | struct simple_com *Simple; |
| 109 | struct function_def *Function_def; |
| 110 | struct group_com *Group; |
| 111 | #if defined (SELECT_COMMAND) |
| 112 | struct select_com *Select; |
| 113 | #endif |
| 114 | } value; |
| 115 | } COMMAND; |
| 116 | |
| 117 | /* Structure used to represent the CONNECTION type. */ |
| 118 | typedef struct connection { |
| 119 | int ignore; /* Unused; simplifies make_command (). */ |
| 120 | COMMAND *first; /* Pointer to the first command. */ |
| 121 | COMMAND *second; /* Pointer to the second command. */ |
| 122 | int connector; /* What separates this command from others. */ |
| 123 | } CONNECTION; |
| 124 | |
| 125 | /* Structures used to represent the CASE command. */ |
| 126 | |
| 127 | /* Pattern/action structure for CASE_COM. */ |
| 128 | typedef struct pattern_list { |
| 129 | struct pattern_list *next; /* Clause to try in case this one failed. */ |
| 130 | WORD_LIST *patterns; /* Linked list of patterns to test. */ |
| 131 | COMMAND *action; /* Thing to execute if a pattern matches. */ |
| 132 | } PATTERN_LIST; |
| 133 | |
| 134 | /* The CASE command. */ |
| 135 | typedef struct case_com { |
| 136 | int flags; /* See description of CMD flags. */ |
| 137 | WORD_DESC *word; /* The thing to test. */ |
| 138 | PATTERN_LIST *clauses; /* The clauses to test against, or NULL. */ |
| 139 | } CASE_COM; |
| 140 | |
| 141 | /* FOR command. */ |
| 142 | typedef struct for_com { |
| 143 | int flags; /* See description of CMD flags. */ |
| 144 | WORD_DESC *name; /* The variable name to get mapped over. */ |
| 145 | WORD_LIST *map_list; /* The things to map over. This is never NULL. */ |
| 146 | COMMAND *action; /* The action to execute. |
| 147 | During execution, NAME is bound to successive |
| 148 | members of MAP_LIST. */ |
| 149 | } FOR_COM; |
| 150 | |
| 151 | #if defined (SELECT_COMMAND) |
| 152 | /* KSH SELECT command. */ |
| 153 | typedef struct select_com { |
| 154 | int flags; /* See description of CMD flags. */ |
| 155 | WORD_DESC *name; /* The variable name to get mapped over. */ |
| 156 | WORD_LIST *map_list; /* The things to map over. This is never NULL. */ |
| 157 | COMMAND *action; /* The action to execute. |
| 158 | During execution, NAME is bound to the member of |
| 159 | MAP_LIST chosen by the user. */ |
| 160 | } SELECT_COM; |
| 161 | #endif /* SELECT_COMMAND */ |
| 162 | |
| 163 | /* IF command. */ |
| 164 | typedef struct if_com { |
| 165 | int flags; /* See description of CMD flags. */ |
| 166 | COMMAND *test; /* Thing to test. */ |
| 167 | COMMAND *true_case; /* What to do if the test returned non-zero. */ |
| 168 | COMMAND *false_case; /* What to do if the test returned zero. */ |
| 169 | } IF_COM; |
| 170 | |
| 171 | /* WHILE command. */ |
| 172 | typedef struct while_com { |
| 173 | int flags; /* See description of CMD flags. */ |
| 174 | COMMAND *test; /* Thing to test. */ |
| 175 | COMMAND *action; /* Thing to do while test is non-zero. */ |
| 176 | } WHILE_COM; |
| 177 | |
| 178 | /* The "simple" command. Just a collection of words and redirects. */ |
| 179 | typedef struct simple_com { |
| 180 | int flags; /* See description of CMD flags. */ |
| 181 | WORD_LIST *words; /* The program name, the arguments, |
| 182 | variable assignments, etc. */ |
| 183 | REDIRECT *redirects; /* Redirections to perform. */ |
| 184 | int line; /* line number the command starts on */ |
| 185 | } SIMPLE_COM; |
| 186 | |
| 187 | /* The "function_def" command. This isn't really a command, but it is |
| 188 | represented as such for now. If the function def appears within |
| 189 | `(' `)' the parser tries to set the SUBSHELL bit of the command. That |
| 190 | means that FUNCTION_DEF has to be run through the executor. Maybe this |
| 191 | command should be defined in a subshell. Who knows or cares. */ |
| 192 | typedef struct function_def { |
| 193 | int ignore; /* See description of CMD flags. */ |
| 194 | WORD_DESC *name; /* The name of the function. */ |
| 195 | COMMAND *command; /* The parsed execution tree. */ |
| 196 | } FUNCTION_DEF; |
| 197 | |
| 198 | /* A command that is `grouped' allows pipes to take effect over |
| 199 | the entire command structure. */ |
| 200 | typedef struct group_com { |
| 201 | int ignore; /* See description of CMD flags. */ |
| 202 | COMMAND *command; |
| 203 | } GROUP_COM; |
| 204 | |
| 205 | extern COMMAND *global_command; |
| 206 | |
| 207 | /* Forward declarations of functions declared in copy_cmd.c. */ |
| 208 | |
| 209 | extern WORD_DESC *copy_word __P((WORD_DESC *)); |
| 210 | extern WORD_LIST *copy_word_list __P((WORD_LIST *)); |
| 211 | extern REDIRECT *copy_redirect __P((REDIRECT *)); |
| 212 | extern REDIRECT *copy_redirects __P((REDIRECT *)); |
| 213 | extern COMMAND *copy_command __P((COMMAND *)); |
| 214 | |
| 215 | #endif /* _COMMAND_H */ |