/* command.h -- The structures used internally to represent commands, and the extern declarations of the functions used to create them. */ /* Copyright (C) 1993-2021 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 3 of the License, 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. If not, see <http://www.gnu.org/licenses/>. */ #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, r_append_err_and_out }; /* Redirection flags; values for rflags */ #define REDIR_VARASSIGN 0x01 /* 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 BADVAR_REDIRECT -5 /* something wrong with {varname}redir */ #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 || ri == r_append_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_append_err_and_out || \ 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, cm_coproc }; /* Possible values for the `flags' field of a WORD_DESC. */ #define W_HASDOLLAR (1 << 0) /* Dollar sign present. */ #define W_QUOTED (1 << 1) /* Some form of quote character is present. */ #define W_ASSIGNMENT (1 << 2) /* This word is a variable assignment. */ #define W_SPLITSPACE (1 << 3) /* Split this word on " " regardless of IFS */ #define W_NOSPLIT (1 << 4) /* Do not perform word splitting on this word because ifs is empty string. */ #define W_NOGLOB (1 << 5) /* Do not perform globbing on this word. */ #define W_NOSPLIT2 (1 << 6) /* Don't split word except for $@ expansion (using spaces) because context does not allow it. */ #define W_TILDEEXP (1 << 7) /* Tilde expand this assignment word */ #define W_DOLLARAT (1 << 8) /* UNUSED - $@ and its special handling */ #define W_ARRAYREF (1 << 9) /* word is a valid array reference */ #define W_NOCOMSUB (1 << 10) /* Don't perform command substitution on this word */ #define W_ASSIGNRHS (1 << 11) /* Word is rhs of an assignment statement */ #define W_NOTILDE (1 << 12) /* Don't perform tilde expansion on this word */ #define W_NOASSNTILDE (1 << 13) /* don't do tilde expansion like an assignment statement */ #define W_EXPANDRHS (1 << 14) /* Expanding word in ${paramOPword} */ #define W_COMPASSIGN (1 << 15) /* Compound assignment */ #define W_ASSNBLTIN (1 << 16) /* word is a builtin command that takes assignments */ #define W_ASSIGNARG (1 << 17) /* word is assignment argument to command */ #define W_HASQUOTEDNULL (1 << 18) /* word contains a quoted null character */ #define W_DQUOTE (1 << 19) /* UNUSED - word should be treated as if double-quoted */ #define W_NOPROCSUB (1 << 20) /* don't perform process substitution */ #define W_SAWQUOTEDNULL (1 << 21) /* word contained a quoted null that was removed */ #define W_ASSIGNASSOC (1 << 22) /* word looks like associative array assignment */ #define W_ASSIGNARRAY (1 << 23) /* word looks like a compound indexed array assignment */ #define W_ARRAYIND (1 << 24) /* word is an array index being expanded */ #define W_ASSNGLOBAL (1 << 25) /* word is a global assignment to declare (declare/typeset -g) */ #define W_NOBRACE (1 << 26) /* Don't perform brace expansion */ #define W_COMPLETE (1 << 27) /* word is being expanded for completion */ #define W_CHKLOCAL (1 << 28) /* check for local vars on assignment */ #define W_FORCELOCAL (1 << 29) /* force assignments to be to local variables, non-fatal on assignment errors */ /* UNUSED (1 << 30) */ /* Flags for the `pflags' argument to param_expand() and various parameter_brace_expand_xxx functions; also used for string_list_dollar_at */ #define PF_NOCOMSUB 0x01 /* Do not perform command substitution */ #define PF_IGNUNBOUND 0x02 /* ignore unbound vars even if -u set */ #define PF_NOSPLIT2 0x04 /* same as W_NOSPLIT2 */ #define PF_ASSIGNRHS 0x08 /* same as W_ASSIGNRHS */ #define PF_COMPLETE 0x10 /* same as W_COMPLETE, sets SX_COMPLETE */ #define PF_EXPANDRHS 0x20 /* same as W_EXPANDRHS */ #define PF_ALLINDS 0x40 /* array, act as if [@] was supplied */ /* 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 */ #define SUBSHELL_PROCSUB 0x20 /* subshell caused by <(command) or >(command) */ #define SUBSHELL_COPROC 0x40 /* subshell from a coproc pipeline */ #define SUBSHELL_RESETTRAP 0x80 /* subshell needs to reset trap strings on first call to trap */ #define SUBSHELL_IGNTRAP 0x100 /* subshell should reset trapped signals from trap_handler */ /* 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. */ REDIRECTEE redirector; /* Descriptor or varname to be redirected. */ int rflags; /* Private flags for this redirection */ 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 */ #define CMD_COPROC_SUBSHELL 0x1000 #define CMD_LASTPIPE 0x2000 #define CMD_STDPATH 0x4000 /* use standard path for command lookup */ #define CMD_TRY_OPTIMIZING 0x8000 /* try to optimize this simple command */ /* 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; struct coproc_com *Coproc; } 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. */ /* Values for FLAGS word in a PATTERN_LIST */ #define CASEPAT_FALLTHROUGH 0x01 #define CASEPAT_TESTNEXT 0x02 /* 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 slipped 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; int line; COMMAND *command; } SUBSHELL_COM; #define COPROC_RUNNING 0x01 #define COPROC_DEAD 0x02 typedef struct coproc { char *c_name; pid_t c_pid; int c_rfd; int c_wfd; int c_rsave; int c_wsave; int c_flags; int c_status; int c_lock; } Coproc; typedef struct coproc_com { int flags; char *name; COMMAND *command; } COPROC_COM; extern COMMAND *global_command; extern Coproc sh_coproc; /* 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 PARAMS((FUNCTION_DEF *, FUNCTION_DEF *)); extern FUNCTION_DEF *copy_function_def PARAMS((FUNCTION_DEF *)); extern WORD_DESC *copy_word PARAMS((WORD_DESC *)); extern WORD_LIST *copy_word_list PARAMS((WORD_LIST *)); extern REDIRECT *copy_redirect PARAMS((REDIRECT *)); extern REDIRECT *copy_redirects PARAMS((REDIRECT *)); extern COMMAND *copy_command PARAMS((COMMAND *)); #endif /* _COMMAND_H_ */