/* command.h -- The structures used internally to represent commands, and the extern declarations of the functions used to create them. */ #if !defined (_COMMAND_H) #define _COMMAND_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 }; /* Command Types: */ enum command_type { cm_for, cm_case, cm_while, cm_if, cm_simple, cm_connection, cm_function_def, cm_until, cm_group }; /* A structure which represents a word. */ typedef struct word_desc { char *word; /* Zero terminated string. */ int dollar_present; /* Non-zero means dollar sign present. */ int quoted; /* Non-zero means single, double, or back quote or backslash is present. */ int assignment; /* Non-zero means that this word contains an assignment. */ } 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 <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 */ /* 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; } 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 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_def" command. This isn't really a command, but it is represented as such for now. If the function def appears within `(' `)' the parser tries to set the SUBSHELL bit of the command. That means that FUNCTION_DEF has to be run through the executor. Maybe this command should be defined in a subshell. Who knows or cares. */ 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. */ } FUNCTION_DEF; /* A command that is `grouped' allows pipes to take effect over the entire command structure. */ typedef struct group_com { int ignore; /* See description of CMD flags. */ COMMAND *command; } GROUP_COM; /* Forward declarations of functions called by the grammer. */ extern REDIRECT *make_redirection (), *copy_redirect (), *copy_redirects (); extern WORD_LIST *make_word_list (), *copy_word_list (); extern WORD_DESC *make_word (), *copy_word (); extern char **make_word_array (); extern COMMAND *make_for_command (), *make_case_command (); extern COMMAND *make_if_command (), *make_while_command (); extern COMMAND *command_connect (), *make_simple_command (); extern COMMAND *make_function_def (), *clean_simple_command (); extern COMMAND *make_until_command (), *make_group_command (); extern COMMAND *make_command (), *make_bare_simple_command (); extern COMMAND *copy_command (); extern void make_here_document (); extern PATTERN_LIST *make_pattern_list (); extern COMMAND *global_command; #endif /* _COMMAND_H */