/* shell.h -- The data structures used by the shell */ #include "config.h" #include "general.h" #include "variables.h" #include "quit.h" #include "maxpath.h" #include "unwind_prot.h" extern int EOF_Reached; #define NO_PIPE -1 #define REDIRECT_BOTH -2 #define IS_DESCRIPTOR -1 #define NO_VARIABLE -1 /* A bunch of stuff for flow of control using setjmp () and longjmp (). */ #include extern jmp_buf top_level, catch; #define NOT_JUMPED 0 /* Not returning from a longjmp. */ #define FORCE_EOF 1 /* We want to stop parsing. */ #define DISCARD 2 /* Discard current command. */ #define EXITPROG 3 /* Unconditionally exit the program now. */ /* Values that can be returned by execute_command (). */ #define EXECUTION_FAILURE 1 #define EXECUTION_SUCCESS 0 /* Special exit status used when the shell is asked to execute a binary file as a shell script. */ #define EX_BINARY_FILE 126 /* The list of characters that are quoted in double-quotes with a backslash. Other characters following a backslash cause nothing special to happen. */ #define slashify_in_quotes "\\`$\"" #define slashify_in_here_document "\\`$" /* Constants which specify how to handle backslashes and quoting in expand_word_internal (). Q_DOUBLE_QUOTES means to use the function slashify_in_quotes () to decide whether the backslash should be retained. Q_HERE_DOCUMENT means slashify_in_here_document () to decide whether to retain the backslash. Q_KEEP_BACKSLASH means to unconditionally retain the backslash. */ #define Q_DOUBLE_QUOTES 0x1 #define Q_HERE_DOCUMENT 0x2 #define Q_KEEP_BACKSLASH 0x4 /* All structs which contain a `next' field should have that field as the first field in the struct. This means that functions can be written to handle the general case for linked lists. */ typedef struct g_list { struct g_list *next; } GENERIC_LIST; /* 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 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. */ union { int dest; /* Place to redirect REDIRECTOR to, or ... */ WORD_DESC *filename; /* filename to redirect to. */ } redirectee; 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. */ /* 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. */ 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. */ } 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 (); extern WORD_LIST *make_word_list (); extern WORD_DESC *make_word (); extern COMMAND *make_for_command (), *make_case_command (), *make_if_command (), *make_while_command (), *command_connect (), *make_simple_command (), *make_function_def (), *clean_simple_command (), *make_until_command (), *make_group_command (); extern PATTERN_LIST *make_pattern_list (); extern COMMAND *global_command, *copy_command (); extern char **shell_environment; extern WORD_LIST *rest_of_args; /* Generalized global variables. */ extern int executing, login_shell; /* Structure to pass around that holds a bitmap of file descriptors to close, and the size of that structure. Used in execute_cmd.c. */ struct fd_bitmap { long size; char *bitmap; }; #define FD_BITMAP_SIZE 32