[thirdparty/bash.git] / command.h

/* command.h -- The structures used internally to represent commands, and
   the extern declarations of the functions used to create them. */

/* Copyright (C) 1993 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, 675 Mass Ave, Cambridge, MA 02139, 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_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
};

/* 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 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)

/* 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 };

/* Possible values for the `flags' field of a WORD_DESC. */
#define W_HASDOLLAR	0x01	/* Dollar sign present. */
#define W_QUOTED	0x02	/* Some form of quote character is present. */
#define W_ASSIGNMENT	0x04	/* This word is a variable assignment. */
#define W_GLOBEXP	0x08	/* This word is the result of a glob expansion. */
#define W_NOSPLIT	0x10	/* Do not perform word splitting on this word. */

/* 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 */

/* 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 FLAGS is IS_DESCRIPTOR,
   then we use REDIRECTEE.DEST, else we use the file specified. */

typedef union {
  long dest;			/* Place to redirect REDIRECTOR to, or ... */
  WORD_DESC *filename;		/* filename to redirect to. */
} REDIRECTEE;

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 */

/* 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
  } 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. */
} PATTERN_LIST;

/* The CASE command. */
typedef struct case_com {
  int flags;			/* See description of CMD flags. */
  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. */
  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 (SELECT_COMMAND)
/* KSH SELECT command. */
typedef struct select_com {
  int flags;		/* See description of CMD flags. */
  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;

/* The "simple" command.  Just a collection of words and redirects. */
typedef struct simple_com {
  int flags;			/* See description of CMD flags. */
  WORD_LIST *words;		/* The program name, the arguments,
				   variable assignments, etc. */
  REDIRECT *redirects;		/* Redirections to perform. */
  int line;			/* line number the command starts on */
} SIMPLE_COM;

/* The "function definition" command. */
typedef struct function_def {
  int ignore;			/* See description of CMD flags. */
  WORD_DESC *name;		/* The name of the function. */
  COMMAND *command;		/* The parsed execution tree. */
  int line;			/* Line number the function def starts on. */
} 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;

extern COMMAND *global_command;

/* Forward declarations of functions declared in copy_cmd.c. */

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_ */
Commit	Line	Data
726f6388 JA	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
ccc6cda3 JA	22	#if !defined (_COMMAND_H_)
ccc6cda3 JA	23	#define _COMMAND_H_
726f6388 JA	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
ccc6cda3 JA	36	/* Redirection errors. */
	37	#define AMBIGUOUS_REDIRECT -1
	38	#define NOCLOBBER_REDIRECT -2
	39	#define RESTRICTED_REDIRECT -3 /* can only happen in restricted shells. */
d166f048	40	#define HEREDOC_REDIRECT -4 /* here-doc temp file can't be created */
ccc6cda3 JA	41
	42	#define OUTPUT_REDIRECT(ri) \
	43	(ri == r_output_direction \|\| ri == r_input_output \|\| ri == r_err_and_out)
	44
	45	#define INPUT_REDIRECT(ri) \
	46	(ri == r_input_direction \|\| ri == r_inputa_direction \|\| ri == r_input_output)
	47
	48	#define WRITE_REDIRECT(ri) \
	49	(ri == r_output_direction \|\| \
	50	ri == r_input_output \|\| \
	51	ri == r_err_and_out \|\| \
	52	ri == r_appending_to \|\| \
	53	ri == r_output_force)
	54
726f6388 JA	55	/* Command Types: */
	56	enum command_type { cm_for, cm_case, cm_while, cm_if, cm_simple, cm_select,
	57	cm_connection, cm_function_def, cm_until, cm_group };
	58
ccc6cda3 JA	59	/* Possible values for the `flags' field of a WORD_DESC. */
	60	#define W_HASDOLLAR 0x01 /* Dollar sign present. */
	61	#define W_QUOTED 0x02 /* Some form of quote character is present. */
	62	#define W_ASSIGNMENT 0x04 /* This word is a variable assignment. */
	63	#define W_GLOBEXP 0x08 /* This word is the result of a glob expansion. */
	64	#define W_NOSPLIT 0x10 /* Do not perform word splitting on this word. */
	65
	66	/* Possible values for subshell_environment */
	67	#define SUBSHELL_ASYNC 0x01 /* subshell caused by `command &' */
	68	#define SUBSHELL_PAREN 0x02 /* subshell caused by ( ... ) */
	69	#define SUBSHELL_COMSUB 0x04 /* subshell caused by `command` or $(command) */
	70	#define SUBSHELL_FORK 0x08 /* subshell caused by executing a disk command */
	71
726f6388 JA	72	/* A structure which represents a word. */
	73	typedef struct word_desc {
	74	char word; / Zero terminated string. */
ccc6cda3	75	int flags; /* Flags associated with this word. */
726f6388 JA	76	} WORD_DESC;
	77
	78	/* A linked list of words. */
	79	typedef struct word_list {
	80	struct word_list *next;
	81	WORD_DESC *word;
	82	} WORD_LIST;
	83
	84
	85	/* **************************************************************** */
	86	/* */
	87	/* Shell Command Structs */
	88	/* */
	89	/* **************************************************************** */
	90
	91	/* What a redirection descriptor looks like. If FLAGS is IS_DESCRIPTOR,
	92	then we use REDIRECTEE.DEST, else we use the file specified. */
	93
	94	typedef union {
	95	long dest; /* Place to redirect REDIRECTOR to, or ... */
	96	WORD_DESC filename; / filename to redirect to. */
	97	} REDIRECTEE;
	98
	99	typedef struct redirect {
	100	struct redirect next; / Next element, or NULL. */
	101	int redirector; /* Descriptor to be redirected. */
	102	int flags; /* Flag value for `open'. */
	103	enum r_instruction instruction; /* What to do with the information. */
	104	REDIRECTEE redirectee; /* File descriptor or filename */
	105	char here_doc_eof; / The word that appeared in <<foo. */
	106	} REDIRECT;
	107
	108	/* An element used in parsing. A single word or a single redirection.
	109	This is an ephemeral construct. */
	110	typedef struct element {
	111	WORD_DESC *word;
	112	REDIRECT *redirect;
	113	} ELEMENT;
	114
	115	/* Possible values for command->flags. */
	116	#define CMD_WANT_SUBSHELL 0x01 /* User wants a subshell: ( command ) */
	117	#define CMD_FORCE_SUBSHELL 0x02 /* Shell needs to force a subshell. */
	118	#define CMD_INVERT_RETURN 0x04 /* Invert the exit value. */
	119	#define CMD_IGNORE_RETURN 0x08 /* Ignore the exit value. For set -e. */
	120	#define CMD_NO_FUNCTIONS 0x10 /* Ignore functions during command lookup. */
	121	#define CMD_INHIBIT_EXPANSION 0x20 /* Do not expand the command words. */
	122	#define CMD_NO_FORK 0x40 /* Don't fork; just call execve */
ccc6cda3 JA	123	#define CMD_TIME_PIPELINE 0x80 /* Time a pipeline */
ccc6cda3 JA	124	#define CMD_TIME_POSIX 0x100 /* time -p; use POSIX.2 time output spec. */
d166f048 JA	125	#define CMD_AMPERSAND 0x200 /* command & */
d166f048 JA	126	#define CMD_STDIN_REDIR 0x400 /* async command needs implicit </dev/null */
726f6388 JA	127
	128	/* What a command looks like. */
	129	typedef struct command {
	130	enum command_type type; /* FOR CASE WHILE IF CONNECTION or SIMPLE. */
	131	int flags; /* Flags controlling execution environment. */
	132	int line; /* line number the command starts on */
	133	REDIRECT redirects; / Special redirects for FOR CASE, etc. */
	134	union {
	135	struct for_com *For;
	136	struct case_com *Case;
	137	struct while_com *While;
	138	struct if_com *If;
	139	struct connection *Connection;
	140	struct simple_com *Simple;
	141	struct function_def *Function_def;
	142	struct group_com *Group;
	143	#if defined (SELECT_COMMAND)
	144	struct select_com *Select;
	145	#endif
	146	} value;
	147	} COMMAND;
	148
	149	/* Structure used to represent the CONNECTION type. */
	150	typedef struct connection {
	151	int ignore; /* Unused; simplifies make_command (). */
	152	COMMAND first; / Pointer to the first command. */
	153	COMMAND second; / Pointer to the second command. */
	154	int connector; /* What separates this command from others. */
	155	} CONNECTION;
	156
	157	/* Structures used to represent the CASE command. */
	158
	159	/* Pattern/action structure for CASE_COM. */
	160	typedef struct pattern_list {
	161	struct pattern_list next; / Clause to try in case this one failed. */
	162	WORD_LIST patterns; / Linked list of patterns to test. */
	163	COMMAND action; / Thing to execute if a pattern matches. */
	164	} PATTERN_LIST;
	165
	166	/* The CASE command. */
	167	typedef struct case_com {
	168	int flags; /* See description of CMD flags. */
	169	WORD_DESC word; / The thing to test. */
	170	PATTERN_LIST clauses; / The clauses to test against, or NULL. */
	171	} CASE_COM;
	172
	173	/* FOR command. */
	174	typedef struct for_com {
	175	int flags; /* See description of CMD flags. */
	176	WORD_DESC name; / The variable name to get mapped over. */
	177	WORD_LIST map_list; / The things to map over. This is never NULL. */
	178	COMMAND action; / The action to execute.
	179	During execution, NAME is bound to successive
	180	members of MAP_LIST. */
	181	} FOR_COM;
	182
	183	#if defined (SELECT_COMMAND)
	184	/* KSH SELECT command. */
	185	typedef struct select_com {
	186	int flags; /* See description of CMD flags. */
	187	WORD_DESC name; / The variable name to get mapped over. */
	188	WORD_LIST map_list; / The things to map over. This is never NULL. */
	189	COMMAND action; / The action to execute.
	190	During execution, NAME is bound to the member of
191	MAP_LIST chosen by the user. */
192	} SELECT_COM;
193	#endif /* SELECT_COMMAND */
194
195	/* IF command. */
196	typedef struct if_com {
197	int flags; /* See description of CMD flags. */
198	COMMAND test; / Thing to test. */
199	COMMAND true_case; / What to do if the test returned non-zero. */
200	COMMAND false_case; / What to do if the test returned zero. */
201	} IF_COM;
202
203	/* WHILE command. */
204	typedef struct while_com {
205	int flags; /* See description of CMD flags. */
206	COMMAND test; / Thing to test. */
207	COMMAND action; / Thing to do while test is non-zero. */
208	} WHILE_COM;
209
210	/* The "simple" command. Just a collection of words and redirects. */
211	typedef struct simple_com {
212	int flags; /* See description of CMD flags. */
213	WORD_LIST words; / The program name, the arguments,
214	variable assignments, etc. */
215	REDIRECT redirects; / Redirections to perform. */
216	int line; /* line number the command starts on */
217	} SIMPLE_COM;
218
ccc6cda3	219	/* The "function definition" command. */
726f6388 JA	220	typedef struct function_def {
	221	int ignore; /* See description of CMD flags. */
	222	WORD_DESC name; / The name of the function. */
	223	COMMAND command; / The parsed execution tree. */
ccc6cda3	224	int line; /* Line number the function def starts on. */
726f6388 JA	225	} FUNCTION_DEF;
726f6388 JA	226
ccc6cda3 JA	227	/* A command that is `grouped' allows pipes and redirections to affect all
ccc6cda3 JA	228	commands in the group. */
726f6388 JA	229	typedef struct group_com {
	230	int ignore; /* See description of CMD flags. */
	231	COMMAND *command;
	232	} GROUP_COM;
	233
	234	extern COMMAND *global_command;
	235
	236	/* Forward declarations of functions declared in copy_cmd.c. */
	237
	238	extern WORD_DESC copy_word __P((WORD_DESC ));
	239	extern WORD_LIST copy_word_list __P((WORD_LIST ));
	240	extern REDIRECT copy_redirect __P((REDIRECT ));
	241	extern REDIRECT copy_redirects __P((REDIRECT ));
	242	extern COMMAND copy_command __P((COMMAND ));
	243
ccc6cda3	244	#endif /* _COMMAND_H_ */