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Diffstat (limited to 'command.h')
| -rw-r--r-- | command.h | 345 |
1 files changed, 345 insertions, 0 deletions
diff --git a/command.h b/command.h new file mode 100644 index 0000000..a5bac0b --- /dev/null +++ b/command.h @@ -0,0 +1,345 @@ +/* command.h -- The structures used internally to represent commands, and + the extern declarations of the functions used to create them. */ + +/* Copyright (C) 1993-2005 Free Software Foundation, Inc. + + This file is part of GNU Bash, the Bourne Again SHell. + + Bash is free software; you can redistribute it and/or modify it under + the terms of the GNU General Public License as published by the Free + Software Foundation; either version 2, or (at your option) any later + version. + + Bash is distributed in the hope that it will be useful, but WITHOUT ANY + WARRANTY; without even the implied warranty of MERCHANTABILITY or + FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + for more details. + + You should have received a copy of the GNU General Public License along + with Bash; see the file COPYING. If not, write to the Free Software + Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA. */ + +#if !defined (_COMMAND_H_) +#define _COMMAND_H_ + +#include "stdc.h" + +/* Instructions describing what kind of thing to do for a redirection. */ +enum r_instruction { + r_output_direction, r_input_direction, r_inputa_direction, + r_appending_to, r_reading_until, r_reading_string, + r_duplicating_input, r_duplicating_output, r_deblank_reading_until, + r_close_this, r_err_and_out, r_input_output, r_output_force, + r_duplicating_input_word, r_duplicating_output_word, + r_move_input, r_move_output, r_move_input_word, r_move_output_word +}; + +/* Redirection errors. */ +#define AMBIGUOUS_REDIRECT -1 +#define NOCLOBBER_REDIRECT -2 +#define RESTRICTED_REDIRECT -3 /* can only happen in restricted shells. */ +#define HEREDOC_REDIRECT -4 /* here-doc temp file can't be created */ + +#define CLOBBERING_REDIRECT(ri) \ + (ri == r_output_direction || ri == r_err_and_out) + +#define OUTPUT_REDIRECT(ri) \ + (ri == r_output_direction || ri == r_input_output || ri == r_err_and_out) + +#define INPUT_REDIRECT(ri) \ + (ri == r_input_direction || ri == r_inputa_direction || ri == r_input_output) + +#define WRITE_REDIRECT(ri) \ + (ri == r_output_direction || \ + ri == r_input_output || \ + ri == r_err_and_out || \ + ri == r_appending_to || \ + ri == r_output_force) + +/* redirection needs translation */ +#define TRANSLATE_REDIRECT(ri) \ + (ri == r_duplicating_input_word || ri == r_duplicating_output_word || \ + ri == r_move_input_word || ri == r_move_output_word) + +/* Command Types: */ +enum command_type { cm_for, cm_case, cm_while, cm_if, cm_simple, cm_select, + cm_connection, cm_function_def, cm_until, cm_group, + cm_arith, cm_cond, cm_arith_for, cm_subshell }; + +/* Possible values for the `flags' field of a WORD_DESC. */ +#define W_HASDOLLAR 0x00001 /* Dollar sign present. */ +#define W_QUOTED 0x00002 /* Some form of quote character is present. */ +#define W_ASSIGNMENT 0x00004 /* This word is a variable assignment. */ +#define W_GLOBEXP 0x00008 /* This word is the result of a glob expansion. */ +#define W_NOSPLIT 0x00010 /* Do not perform word splitting on this word. */ +#define W_NOGLOB 0x00020 /* Do not perform globbing on this word. */ +#define W_NOSPLIT2 0x00040 /* Don't split word except for $@ expansion. */ +#define W_TILDEEXP 0x00080 /* Tilde expand this assignment word */ +#define W_DOLLARAT 0x00100 /* $@ and its special handling */ +#define W_DOLLARSTAR 0x00200 /* $* and its special handling */ +#define W_NOCOMSUB 0x00400 /* Don't perform command substitution on this word */ +#define W_ASSIGNRHS 0x00800 /* Word is rhs of an assignment statement */ +#define W_NOTILDE 0x01000 /* Don't perform tilde expansion on this word */ +#define W_ITILDE 0x02000 /* Internal flag for word expansion */ +#define W_NOEXPAND 0x04000 /* Don't expand at all -- do quote removal */ +#define W_COMPASSIGN 0x08000 /* Compound assignment */ +#define W_ASSNBLTIN 0x10000 /* word is a builtin command that takes assignments */ +#define W_ASSIGNARG 0x20000 /* word is assignment argument to command */ +#define W_HASQUOTEDNULL 0x40000 /* word contains a quoted null character */ +#define W_DQUOTE 0x80000 /* word should be treated as if double-quoted */ + +/* Possible values for subshell_environment */ +#define SUBSHELL_ASYNC 0x01 /* subshell caused by `command &' */ +#define SUBSHELL_PAREN 0x02 /* subshell caused by ( ... ) */ +#define SUBSHELL_COMSUB 0x04 /* subshell caused by `command` or $(command) */ +#define SUBSHELL_FORK 0x08 /* subshell caused by executing a disk command */ +#define SUBSHELL_PIPE 0x10 /* subshell from a pipeline element */ + +/* A structure which represents a word. */ +typedef struct word_desc { + char *word; /* Zero terminated string. */ + int flags; /* Flags associated with this word. */ +} WORD_DESC; + +/* A linked list of words. */ +typedef struct word_list { + struct word_list *next; + WORD_DESC *word; +} WORD_LIST; + + +/* **************************************************************** */ +/* */ +/* Shell Command Structs */ +/* */ +/* **************************************************************** */ + +/* What a redirection descriptor looks like. If the redirection instruction + is ri_duplicating_input or ri_duplicating_output, use DEST, otherwise + use the file in FILENAME. Out-of-range descriptors are identified by a + negative DEST. */ + +typedef union { + int dest; /* Place to redirect REDIRECTOR to, or ... */ + WORD_DESC *filename; /* filename to redirect to. */ +} REDIRECTEE; + +/* Structure describing a redirection. If REDIRECTOR is negative, the parser + (or translator in redir.c) encountered an out-of-range file descriptor. */ +typedef struct redirect { + struct redirect *next; /* Next element, or NULL. */ + int redirector; /* Descriptor to be redirected. */ + int flags; /* Flag value for `open'. */ + enum r_instruction instruction; /* What to do with the information. */ + REDIRECTEE redirectee; /* File descriptor or filename */ + char *here_doc_eof; /* The word that appeared in <<foo. */ +} REDIRECT; + +/* An element used in parsing. A single word or a single redirection. + This is an ephemeral construct. */ +typedef struct element { + WORD_DESC *word; + REDIRECT *redirect; +} ELEMENT; + +/* Possible values for command->flags. */ +#define CMD_WANT_SUBSHELL 0x01 /* User wants a subshell: ( command ) */ +#define CMD_FORCE_SUBSHELL 0x02 /* Shell needs to force a subshell. */ +#define CMD_INVERT_RETURN 0x04 /* Invert the exit value. */ +#define CMD_IGNORE_RETURN 0x08 /* Ignore the exit value. For set -e. */ +#define CMD_NO_FUNCTIONS 0x10 /* Ignore functions during command lookup. */ +#define CMD_INHIBIT_EXPANSION 0x20 /* Do not expand the command words. */ +#define CMD_NO_FORK 0x40 /* Don't fork; just call execve */ +#define CMD_TIME_PIPELINE 0x80 /* Time a pipeline */ +#define CMD_TIME_POSIX 0x100 /* time -p; use POSIX.2 time output spec. */ +#define CMD_AMPERSAND 0x200 /* command & */ +#define CMD_STDIN_REDIR 0x400 /* async command needs implicit </dev/null */ +#define CMD_COMMAND_BUILTIN 0x0800 /* command executed by `command' builtin */ + +/* What a command looks like. */ +typedef struct command { + enum command_type type; /* FOR CASE WHILE IF CONNECTION or SIMPLE. */ + int flags; /* Flags controlling execution environment. */ + int line; /* line number the command starts on */ + REDIRECT *redirects; /* Special redirects for FOR CASE, etc. */ + union { + struct for_com *For; + struct case_com *Case; + struct while_com *While; + struct if_com *If; + struct connection *Connection; + struct simple_com *Simple; + struct function_def *Function_def; + struct group_com *Group; +#if defined (SELECT_COMMAND) + struct select_com *Select; +#endif +#if defined (DPAREN_ARITHMETIC) + struct arith_com *Arith; +#endif +#if defined (COND_COMMAND) + struct cond_com *Cond; +#endif +#if defined (ARITH_FOR_COMMAND) + struct arith_for_com *ArithFor; +#endif + struct subshell_com *Subshell; + } value; +} COMMAND; + +/* Structure used to represent the CONNECTION type. */ +typedef struct connection { + int ignore; /* Unused; simplifies make_command (). */ + COMMAND *first; /* Pointer to the first command. */ + COMMAND *second; /* Pointer to the second command. */ + int connector; /* What separates this command from others. */ +} CONNECTION; + +/* Structures used to represent the CASE command. */ + +/* Pattern/action structure for CASE_COM. */ +typedef struct pattern_list { + struct pattern_list *next; /* Clause to try in case this one failed. */ + WORD_LIST *patterns; /* Linked list of patterns to test. */ + COMMAND *action; /* Thing to execute if a pattern matches. */ + int flags; +} PATTERN_LIST; + +/* The CASE command. */ +typedef struct case_com { + int flags; /* See description of CMD flags. */ + int line; /* line number the `case' keyword appears on */ + WORD_DESC *word; /* The thing to test. */ + PATTERN_LIST *clauses; /* The clauses to test against, or NULL. */ +} CASE_COM; + +/* FOR command. */ +typedef struct for_com { + int flags; /* See description of CMD flags. */ + int line; /* line number the `for' keyword appears on */ + WORD_DESC *name; /* The variable name to get mapped over. */ + WORD_LIST *map_list; /* The things to map over. This is never NULL. */ + COMMAND *action; /* The action to execute. + During execution, NAME is bound to successive + members of MAP_LIST. */ +} FOR_COM; + +#if defined (ARITH_FOR_COMMAND) +typedef struct arith_for_com { + int flags; + int line; /* generally used for error messages */ + WORD_LIST *init; + WORD_LIST *test; + WORD_LIST *step; + COMMAND *action; +} ARITH_FOR_COM; +#endif + +#if defined (SELECT_COMMAND) +/* KSH SELECT command. */ +typedef struct select_com { + int flags; /* See description of CMD flags. */ + int line; /* line number the `select' keyword appears on */ + WORD_DESC *name; /* The variable name to get mapped over. */ + WORD_LIST *map_list; /* The things to map over. This is never NULL. */ + COMMAND *action; /* The action to execute. + During execution, NAME is bound to the member of + MAP_LIST chosen by the user. */ +} SELECT_COM; +#endif /* SELECT_COMMAND */ + +/* IF command. */ +typedef struct if_com { + int flags; /* See description of CMD flags. */ + COMMAND *test; /* Thing to test. */ + COMMAND *true_case; /* What to do if the test returned non-zero. */ + COMMAND *false_case; /* What to do if the test returned zero. */ +} IF_COM; + +/* WHILE command. */ +typedef struct while_com { + int flags; /* See description of CMD flags. */ + COMMAND *test; /* Thing to test. */ + COMMAND *action; /* Thing to do while test is non-zero. */ +} WHILE_COM; + +#if defined (DPAREN_ARITHMETIC) +/* The arithmetic evaluation command, ((...)). Just a set of flags and + a WORD_LIST, of which the first element is the only one used, for the + time being. */ +typedef struct arith_com { + int flags; + int line; + WORD_LIST *exp; +} ARITH_COM; +#endif /* DPAREN_ARITHMETIC */ + +/* The conditional command, [[...]]. This is a binary tree -- we slippped + a recursive-descent parser into the YACC grammar to parse it. */ +#define COND_AND 1 +#define COND_OR 2 +#define COND_UNARY 3 +#define COND_BINARY 4 +#define COND_TERM 5 +#define COND_EXPR 6 + +typedef struct cond_com { + int flags; + int line; + int type; + WORD_DESC *op; + struct cond_com *left, *right; +} COND_COM; + +/* The "simple" command. Just a collection of words and redirects. */ +typedef struct simple_com { + int flags; /* See description of CMD flags. */ + int line; /* line number the command starts on */ + WORD_LIST *words; /* The program name, the arguments, + variable assignments, etc. */ + REDIRECT *redirects; /* Redirections to perform. */ +} SIMPLE_COM; + +/* The "function definition" command. */ +typedef struct function_def { + int flags; /* See description of CMD flags. */ + int line; /* Line number the function def starts on. */ + WORD_DESC *name; /* The name of the function. */ + COMMAND *command; /* The parsed execution tree. */ + char *source_file; /* file in which function was defined, if any */ +} FUNCTION_DEF; + +/* A command that is `grouped' allows pipes and redirections to affect all + commands in the group. */ +typedef struct group_com { + int ignore; /* See description of CMD flags. */ + COMMAND *command; +} GROUP_COM; + +typedef struct subshell_com { + int flags; + COMMAND *command; +} SUBSHELL_COM; + +extern COMMAND *global_command; + +/* Possible command errors */ +#define CMDERR_DEFAULT 0 +#define CMDERR_BADTYPE 1 +#define CMDERR_BADCONN 2 +#define CMDERR_BADJUMP 3 + +#define CMDERR_LAST 3 + +/* Forward declarations of functions declared in copy_cmd.c. */ + +extern FUNCTION_DEF *copy_function_def_contents __P((FUNCTION_DEF *, FUNCTION_DEF *)); +extern FUNCTION_DEF *copy_function_def __P((FUNCTION_DEF *)); + +extern WORD_DESC *copy_word __P((WORD_DESC *)); +extern WORD_LIST *copy_word_list __P((WORD_LIST *)); +extern REDIRECT *copy_redirect __P((REDIRECT *)); +extern REDIRECT *copy_redirects __P((REDIRECT *)); +extern COMMAND *copy_command __P((COMMAND *)); + +#endif /* _COMMAND_H_ */ |