mksh/sh.h

/*	$OpenBSD: sh.h,v 1.28 2005/10/04 20:35:11 otto Exp $	*/
/*	$OpenBSD: shf.h,v 1.5 2005/03/30 17:16:37 deraadt Exp $	*/
/*	$OpenBSD: table.h,v 1.6 2004/12/18 20:55:52 millert Exp $	*/
/*	$OpenBSD: tree.h,v 1.10 2005/03/28 21:28:22 deraadt Exp $	*/
/*	$OpenBSD: expand.h,v 1.6 2005/03/30 17:16:37 deraadt Exp $	*/
/*	$OpenBSD: lex.h,v 1.10 2005/09/11 18:02:27 otto Exp $	*/
/*	$OpenBSD: proto.h,v 1.27 2005/10/06 06:39:36 otto Exp $	*/
/*	$OpenBSD: c_test.h,v 1.4 2004/12/20 11:34:26 otto Exp $	*/
/*	$OpenBSD: tty.h,v 1.5 2004/12/20 11:34:26 otto Exp $	*/

#define	MKSH_SH_H_ID	"$MirOS: src/bin/mksh/sh.h,v 1.23 2005/11/22 18:40:43 tg Exp $"

#if defined(__INTERIX) && !defined(_ALL_SOURCE)
#define _ALL_SOURCE
#endif

#include <sys/param.h>

#if defined(__gnu_linux__) && !defined(_POSIX_SOURCE)
#define _POSIX_SOURCE
#endif

#ifndef __RCSID
#define	__RCSID(x)	static const char __rcsid[] __attribute__((used)) = (x)
#endif

#include <sys/time.h>
#include <sys/file.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/resource.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <ctype.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <libgen.h>
#include <limits.h>
#if !defined(__sun__)
#include <paths.h>
#endif
#include <pwd.h>
#include <setjmp.h>
#include <signal.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <termios.h>
#include <time.h>
#include <unistd.h>
#if defined(NEED_COMPAT)
#include "compat.h"
#endif

/* some useful #defines */
#ifdef EXTERN
# define I__(i) = i
#else
# define I__(i)
# define EXTERN extern
# define EXTERN_DEFINED
#endif

#define EXECSHELL	"/bin/mksh"
#define EXECSHELL_STR	"EXECSHELL"

#define	NELEM(a)	(sizeof(a) / sizeof((a)[0]))
#define	sizeofN(type, n) (sizeof(type) * (n))
#define	BIT(i)		(1<<(i))	/* define bit in flag */

/* Table flag type - needs > 16 and < 32 bits */
typedef int32_t Tflag;

#define	NUFILE		32	/* Number of user-accessible files */
#define	FDBASE		10	/* First file usable by Shell */

/* Make MAGIC a char that might be printed to make bugs more obvious, but
 * not a char that is used often.  Also, can't use the high bit as it causes
 * portability problems (calling strchr(x, 0x80|'x') is error prone).
 */
#define	MAGIC		(7)	/* prefix for *?[!{,} during expand */
#define ISMAGIC(c)	((unsigned char)(c) == MAGIC)
#define	NOT		'!'	/* might use ^ (ie, [!...] vs [^..]) */

#define	LINE		4096	/* input line size */
#ifndef PATH_MAX
#define	PATH_MAX	1024	/* pathname size (todo: PATH_MAX/pathconf()) */
#endif
#ifndef _PATH_DEFPATH
#define	_PATH_DEFPATH	"/bin:/usr/bin:/sbin:/usr/sbin"
#endif

EXTERN	char *	kshname;	/* $0 */
EXTERN	pid_t	kshpid;		/* $$, shell pid */
EXTERN	pid_t	procpid;	/* pid of executing process */
EXTERN	uid_t	ksheuid;	/* effective uid of shell */
EXTERN	uid_t	kshuid;		/* real uid of shell */
EXTERN	gid_t	kshegid;	/* effective gid of shell */
EXTERN	gid_t	kshgid;		/* real gid of shell */
EXTERN	int	exstat;		/* exit status */
EXTERN	int	subst_exstat;	/* exit status of last $(..)/`..` */
EXTERN	const char *safe_prompt; /* safe prompt if PS1 substitution fails */

/*
 * Area-based allocation built on malloc/free
 */
typedef struct Area {
	struct link *freelist;	/* free list */
} Area;

EXTERN	Area	aperm;		/* permanent object space */
#define	APERM	&aperm
#define	ATEMP	&e->area

/*
 * parsing & execution environment
 */
EXTERN	struct env {
	short	type;			/* environment type - see below */
	short	flags;			/* EF_* */
	Area	area;			/* temporary allocation area */
	struct	block *loc;		/* local variables and functions */
	short  *savefd;			/* original redirected fds */
	struct	env *oenv;		/* link to previous environment */
	sigjmp_buf jbuf;		/* long jump back to env creator */
	struct temp *temps;		/* temp files */
} *e;

/* struct env.type values */
#define	E_NONE	0		/* dummy environment */
#define	E_PARSE	1		/* parsing command # */
#define	E_FUNC	2		/* executing function # */
#define	E_INCL	3		/* including a file via . # */
#define	E_EXEC	4		/* executing command tree */
#define	E_LOOP	5		/* executing for/while # */
#define	E_ERRH	6		/* general error handler # */
/* # indicates env has valid jbuf (see unwind()) */

/* struct env.flag values */
#define EF_FUNC_PARSE	BIT(0)	/* function being parsed */
#define EF_BRKCONT_PASS	BIT(1)	/* set if E_LOOP must pass break/continue on */
#define EF_FAKE_SIGDIE	BIT(2)	/* hack to get info from unwind to quitenv */

/* Do breaks/continues stop at env type e? */
#define STOP_BRKCONT(t)	((t) == E_NONE || (t) == E_PARSE \
			 || (t) == E_FUNC || (t) == E_INCL)
/* Do returns stop at env type e? */
#define STOP_RETURN(t)	((t) == E_FUNC || (t) == E_INCL)

/* values for siglongjmp(e->jbuf, 0) */
#define LRETURN	1		/* return statement */
#define	LEXIT	2		/* exit statement */
#define LERROR	3		/* errorf() called */
#define LLEAVE	4		/* untrappable exit/error */
#define LINTR	5		/* ^C noticed */
#define	LBREAK	6		/* break statement */
#define	LCONTIN	7		/* continue statement */
#define LSHELL	8		/* return to interactive shell() */
#define LAEXPR	9		/* error in arithmetic expression */

/* option processing */
#define OF_CMDLINE	0x01	/* command line */
#define OF_SET		0x02	/* set builtin */
#define OF_SPECIAL	0x04	/* a special variable changing */
#define OF_INTERNAL	0x08	/* set internally by shell */
#define OF_FIRSTTIME	0x10	/* as early as possible, once */
#define OF_ANY		(OF_CMDLINE | OF_SET | OF_SPECIAL | OF_INTERNAL)

struct option {
    const char	*name;	/* long name of option */
    char	c;	/* character flag (if any) */
    short	flags;	/* OF_* */
};
extern const struct option options[];

/*
 * flags (the order of these enums MUST match the order in misc.c(options[]))
 */
enum sh_flag {
	FEXPORT = 0,	/* -a: export all */
	FBRACEEXPAND,	/* enable {} globbing */
	FBGNICE,	/* bgnice */
	FCOMMAND,	/* -c: (invocation) execute specified command */
	FEMACS,		/* emacs command editing */
	FEMACSUSEMETA,	/* use 8th bit as meta */
	FERREXIT,	/* -e: quit on error */
	FGMACS,		/* gmacs command editing */
	FIGNOREEOF,	/* eof does not exit */
	FTALKING,	/* -i: interactive */
	FKEYWORD,	/* -k: name=value anywhere */
	FLOGIN,		/* -l: a login shell */
	FMARKDIRS,	/* mark dirs with / in file name completion */
	FMONITOR,	/* -m: job control monitoring */
	FNOCLOBBER,	/* -C: don't overwrite existing files */
	FNOEXEC,	/* -n: don't execute any commands */
	FNOGLOB,	/* -f: don't do file globbing */
	FNOHUP,		/* -H: don't kill running jobs when login shell exits */
	FNOLOG,		/* don't save functions in history (ignored) */
	FNOTIFY,	/* -b: asynchronous job completion notification */
	FNOUNSET,	/* -u: using an unset var is an error */
	FPHYSICAL,	/* -o physical: don't do logical cds/pwds */
	FPOSIX,		/* -o posix (disabled) */
	FPRIVILEGED,	/* -p: use suid_profile */
	FRESTRICTED,	/* -r: restricted shell */
	FSH,		/* -o sh (disabled) */
	FSTDIN,		/* -s: (invocation) parse stdin */
	FTRACKALL,	/* -h: create tracked aliases for all commands */
	FVERBOSE,	/* -v: echo input */
	FVI,		/* vi command editing */
	FVIRAW,		/* always read in raw mode (ignored) */
	FVISHOW8,	/* display chars with 8th bit set as is (versus M-) */
	FVITABCOMPLETE,	/* enable tab as file name completion char */
	FVIESCCOMPLETE,	/* enable ESC as file name completion in command mode */
	FXTRACE,	/* -x: execution trace */
	FTALKING_I,	/* (internal): initial shell was interactive */
	FNFLAGS		/* (place holder: how many flags are there) */
};

#define Flag(f)	(shell_flags[(int) (f)])

EXTERN	char shell_flags [FNFLAGS];

EXTERN	char	null [] I__("");	/* null value for variable */
EXTERN	char	space [] I__(" ");
EXTERN	char	newline [] I__("\n");
EXTERN	char	slash [] I__("/");

enum temp_type {
	TT_HEREDOC_EXP,	/* expanded heredoc */
	TT_HIST_EDIT	/* temp file used for history editing (fc -e) */
};
typedef enum temp_type Temp_type;
/* temp/heredoc files.  The file is removed when the struct is freed. */
struct temp {
	struct temp	*next;
	struct shf	*shf;
	int		pid;		/* pid of process parsed here-doc */
	Temp_type	type;
	char		*name;
};

/*
 * stdio and our IO routines
 */

#define shl_spare	(&shf_iob[0])	/* for c_read()/c_print() */
#define shl_stdout	(&shf_iob[1])
#define shl_out		(&shf_iob[2])
EXTERN int shl_stdout_ok;

#if defined(__sun__) || defined(__CYGWIN__)
typedef void (*sig_t)(int);
#endif

/*
 * trap handlers
 */
typedef struct trap {
	int	signal;		/* signal number */
	const char *name;	/* short name */
	const char *mess;	/* descriptive name */
	char   *trap;		/* trap command */
	volatile sig_atomic_t set; /* trap pending */
	int	flags;		/* TF_* */
	sig_t cursig;		/* current handler (valid if TF_ORIG_* set) */
	sig_t shtrap;		/* shell signal handler */
} Trap;

/* values for Trap.flags */
#define TF_SHELL_USES	BIT(0)	/* shell uses signal, user can't change */
#define TF_USER_SET	BIT(1)	/* user has (tried to) set trap */
#define TF_ORIG_IGN	BIT(2)	/* original action was SIG_IGN */
#define TF_ORIG_DFL	BIT(3)	/* original action was SIG_DFL */
#define TF_EXEC_IGN	BIT(4)	/* restore SIG_IGN just before exec */
#define TF_EXEC_DFL	BIT(5)	/* restore SIG_DFL just before exec */
#define TF_DFL_INTR	BIT(6)	/* when received, default action is LINTR */
#define TF_TTY_INTR	BIT(7)	/* tty generated signal (see j_waitj) */
#define TF_CHANGED	BIT(8)	/* used by runtrap() to detect trap changes */
#define TF_FATAL	BIT(9)	/* causes termination if not trapped */

/* values for setsig()/setexecsig() flags argument */
#define SS_RESTORE_MASK	0x3	/* how to restore a signal before an exec() */
#define SS_RESTORE_CURR	0	/* leave current handler in place */
#define SS_RESTORE_ORIG	1	/* restore original handler */
#define SS_RESTORE_DFL	2	/* restore to SIG_DFL */
#define SS_RESTORE_IGN	3	/* restore to SIG_IGN */
#define SS_FORCE	BIT(3)	/* set signal even if original signal ignored */
#define SS_USER		BIT(4)	/* user is doing the set (ie, trap command) */
#define SS_SHTRAP	BIT(5)	/* trap for internal use (CHLD,ALRM,WINCH) */

#define SIGEXIT_	0	/* for trap EXIT */
#define SIGERR_		NSIG	/* for trap ERR */

EXTERN	volatile sig_atomic_t trap;	/* traps pending? */
EXTERN	volatile sig_atomic_t intrsig;	/* pending trap interrupts command */
EXTERN	volatile sig_atomic_t fatal_trap;/* received a fatal signal */
extern	Trap	sigtraps[NSIG+1];

/*
 * TMOUT support
 */
/* values for ksh_tmout_state */
enum tmout_enum {
	TMOUT_EXECUTING	= 0,	/* executing commands */
	TMOUT_READING,		/* waiting for input */
	TMOUT_LEAVING		/* have timed out */
};
EXTERN unsigned int ksh_tmout;
EXTERN enum tmout_enum ksh_tmout_state I__(TMOUT_EXECUTING);

/* For "You have stopped jobs" message */
EXTERN int really_exit;

/*
 * fast character classes
 */
#define	C_ALPHA	 BIT(0)		/* a-z_A-Z */
#define	C_DIGIT	 BIT(1)		/* 0-9 */
#define	C_LEX1	 BIT(2)		/* \0 \t\n|&;<>() */
#define	C_VAR1	 BIT(3)		/* *@#!$-? */
#define	C_IFSWS	 BIT(4)		/* \t \n (IFS white space) */
#define	C_SUBOP1 BIT(5)		/* "=-+?" */
#define	C_SUBOP2 BIT(6)		/* "#%" */
#define	C_IFS	 BIT(7)		/* $IFS */
#define	C_QUOTE	 BIT(8)		/*  \n\t"#$&'()*;<>?[]\`| (needing quoting) */

extern	short chtypes[];

#define	ctype(c, t)	!!(chtypes[(unsigned char)(c)]&(t))
#define	letter(c)	ctype(c, C_ALPHA)
#define	digit(c)	ctype(c, C_DIGIT)
#define	letnum(c)	ctype(c, C_ALPHA|C_DIGIT)

EXTERN int ifs0 I__(' ');	/* for "$*" */

/* Argument parsing for built-in commands and getopts command */

/* Values for Getopt.flags */
#define GF_ERROR	BIT(0)	/* call errorf() if there is an error */
#define GF_PLUSOPT	BIT(1)	/* allow +c as an option */
#define GF_NONAME	BIT(2)	/* don't print argv[0] in errors */

/* Values for Getopt.info */
#define GI_MINUS	BIT(0)	/* an option started with -... */
#define GI_PLUS		BIT(1)	/* an option started with +... */
#define GI_MINUSMINUS	BIT(2)	/* arguments were ended with -- */

typedef struct {
	int		optind;
	int		uoptind;/* what user sees in $OPTIND */
	char		*optarg;
	int		flags;	/* see GF_* */
	int		info;	/* see GI_* */
	unsigned int	p;	/* 0 or index into argv[optind - 1] */
	char		buf[2];	/* for bad option OPTARG value */
} Getopt;

EXTERN Getopt builtin_opt;	/* for shell builtin commands */
EXTERN Getopt user_opt;		/* parsing state for getopts builtin command */

/* This for co-processes */

typedef int32_t Coproc_id; /* something that won't (realisticly) wrap */
struct coproc {
	int	read;		/* pipe from co-process's stdout */
	int	readw;		/* other side of read (saved temporarily) */
	int	write;		/* pipe to co-process's stdin */
	Coproc_id id;		/* id of current output pipe */
	int	njobs;		/* number of live jobs using output pipe */
	void    *job;           /* 0 or job of co-process using input pipe */
};
EXTERN struct coproc coproc;

/* Used in jobs.c and by coprocess stuff in exec.c */
EXTERN sigset_t		sm_default, sm_sigchld;

/* name of called builtin function (used by error functions) */
EXTERN char	*builtin_argv0;
EXTERN Tflag	builtin_flag;	/* flags of called builtin (SPEC_BI, etc.) */

/* current working directory, and size of memory allocated for same */
EXTERN char	*current_wd;
EXTERN int	current_wd_size;

/* Minimum required space to work with on a line - if the prompt leaves less
 * space than this on a line, the prompt is truncated.
 */
#define MIN_EDIT_SPACE	7
/* Minimum allowed value for x_cols: 2 for prompt, 3 for " < " at end of line
 */
#define MIN_COLS	(2 + MIN_EDIT_SPACE + 3)
EXTERN	int	x_cols I__(80);	/* tty columns */

/* These to avoid bracket matching problems */
#define OPAREN	'('
#define CPAREN	')'
#define OBRACK	'['
#define CBRACK	']'
#define OBRACE	'{'
#define CBRACE	'}'

/* Determine the location of the system (common) profile */
#define KSH_SYSTEM_PROFILE "/etc/profile"

/* Used by v_evaluate() and setstr() to control action when error occurs */
#define KSH_UNWIND_ERROR	0	/* unwind the stack (longjmp) */
#define KSH_RETURN_ERROR	1	/* return 1/0 for success/failure */

/*
 * Shell file I/O routines
 */

#define SHF_BSIZE	512

#define shf_fileno(shf)	((shf)->fd)
#define shf_setfileno(shf,nfd)	((shf)->fd = (nfd))
#define shf_getc(shf) ((shf)->rnleft > 0 ? (shf)->rnleft--, *(shf)->rp++ : \
			shf_getchar(shf))
#define shf_putc(c, shf)	((shf)->wnleft == 0 ? shf_putchar((c), (shf)) : \
				    ((shf)->wnleft--, *(shf)->wp++ = (c)))
#define shf_eof(shf)		((shf)->flags & SHF_EOF)
#define shf_error(shf)		((shf)->flags & SHF_ERROR)
#define shf_errno(shf)		((shf)->errno_)
#define shf_clearerr(shf)	((shf)->flags &= ~(SHF_EOF | SHF_ERROR))

/* Flags passed to shf_*open() */
#define SHF_RD		0x0001
#define SHF_WR		0x0002
#define SHF_RDWR	(SHF_RD|SHF_WR)
#define SHF_ACCMODE	0x0003		/* mask */
#define SHF_GETFL	0x0004		/* use fcntl() to figure RD/WR flags */
#define SHF_UNBUF	0x0008		/* unbuffered I/O */
#define SHF_CLEXEC	0x0010		/* set close on exec flag */
#define SHF_MAPHI	0x0020		/* make fd > FDBASE (and close orig)
					 * (shf_open() only) */
#define SHF_DYNAMIC	0x0040		/* string: increase buffer as needed */
#define SHF_INTERRUPT	0x0080		/* EINTR in read/write causes error */
/* Flags used internally */
#define SHF_STRING	0x0100		/* a string, not a file */
#define SHF_ALLOCS	0x0200		/* shf and shf->buf were alloc()ed */
#define SHF_ALLOCB	0x0400		/* shf->buf was alloc()ed */
#define SHF_ERROR	0x0800		/* read()/write() error */
#define SHF_EOF		0x1000		/* read eof (sticky) */
#define SHF_READING	0x2000		/* currently reading: rnleft,rp valid */
#define SHF_WRITING	0x4000		/* currently writing: wnleft,wp valid */


struct shf {
	int flags;		/* see SHF_* */
	unsigned char *rp;	/* read: current position in buffer */
	int rbsize;		/* size of buffer (1 if SHF_UNBUF) */
	int rnleft;		/* read: how much data left in buffer */
	unsigned char *wp;	/* write: current position in buffer */
	int wbsize;		/* size of buffer (0 if SHF_UNBUF) */
	int wnleft;		/* write: how much space left in buffer */
	unsigned char *buf;	/* buffer */
	int fd;			/* file descriptor */
	int errno_;		/* saved value of errno after error */
	int bsize;		/* actual size of buf */
	Area *areap;		/* area shf/buf were allocated in */
};

extern struct shf shf_iob[];

struct table {
	Area   *areap;		/* area to allocate entries */
	short	size, nfree;	/* hash size (always 2^^n), free entries */
	struct	tbl **tbls;	/* hashed table items */
};

struct tbl {			/* table item */
	Tflag	flag;		/* flags */
	int	type;		/* command type (see below), base (if INTEGER),
				 * or offset from val.s of value (if EXPORT) */
	Area	*areap;		/* area to allocate from */
	union {
		char *s;	/* string */
		long i;		/* integer */
		int (*f)(char **);	/* int function */
		struct op *t;	/* "function" tree */
	} val;			/* value */
	int	index;		/* index for an array */
	union {
	    int	field;		/* field with for -L/-R/-Z */
	    int errno_;		/* CEXEC/CTALIAS */
	} u2;
	union {
		struct tbl *array;	/* array values */
		char *fpath;		/* temporary path to undef function */
	} u;
	char	name[4];	/* name -- variable length */
};

/* common flag bits */
#define	ALLOC		BIT(0)	/* val.s has been allocated */
#define	DEFINED		BIT(1)	/* is defined in block */
#define	ISSET		BIT(2)	/* has value, vp->val.[si] */
#define	EXPORT		BIT(3)	/* exported variable/function */
#define	TRACE		BIT(4)	/* var: user flagged, func: execution tracing */
/* (start non-common flags at 8) */
/* flag bits used for variables */
#define	SPECIAL		BIT(8)	/* PATH, IFS, SECONDS, etc */
#define	INTEGER		BIT(9)	/* val.i contains integer value */
#define	RDONLY		BIT(10)	/* read-only variable */
#define	LOCAL		BIT(11)	/* for local typeset() */
#define ARRAY		BIT(13)	/* array */
#define LJUST		BIT(14)	/* left justify */
#define RJUST		BIT(15)	/* right justify */
#define ZEROFIL		BIT(16)	/* 0 filled if RJUSTIFY, strip 0s if LJUSTIFY */
#define LCASEV		BIT(17)	/* convert to lower case */
#define UCASEV_AL	BIT(18)/* convert to upper case / autoload function */
#define INT_U		BIT(19)	/* unsigned integer */
#define INT_L		BIT(20)	/* long integer (no-op) */
#define IMPORT		BIT(21)	/* flag to typeset(): no arrays, must have = */
#define LOCAL_COPY	BIT(22)	/* with LOCAL - copy attrs from existing var */
#define EXPRINEVAL	BIT(23)	/* contents currently being evaluated */
#define EXPRLVALUE	BIT(24)	/* useable as lvalue (temp flag) */
/* flag bits used for taliases/builtins/aliases/keywords/functions */
#define KEEPASN		BIT(8)	/* keep command assignments (eg, var=x cmd) */
#define FINUSE		BIT(9)	/* function being executed */
#define FDELETE		BIT(10)	/* function deleted while it was executing */
#define FKSH		BIT(11)	/* function defined with function x (vs x()) */
#define SPEC_BI		BIT(12)	/* a POSIX special builtin */
#define REG_BI		BIT(13)	/* a POSIX regular builtin */
/* Attributes that can be set by the user (used to decide if an unset param
 * should be repoted by set/typeset).  Does not include ARRAY or LOCAL.
 */
#define USERATTRIB	(EXPORT|INTEGER|RDONLY|LJUST|RJUST|ZEROFIL\
			 |LCASEV|UCASEV_AL|INT_U|INT_L)

/* command types */
#define	CNONE	0		/* undefined */
#define	CSHELL	1		/* built-in */
#define	CFUNC	2		/* function */
#define	CEXEC	4		/* executable command */
#define	CALIAS	5		/* alias */
#define	CKEYWD	6		/* keyword */
#define CTALIAS	7		/* tracked alias */

/* Flags for findcom()/comexec() */
#define FC_SPECBI	BIT(0)	/* special builtin */
#define FC_FUNC		BIT(1)	/* function builtin */
#define FC_REGBI	BIT(2)	/* regular builtin */
#define FC_UNREGBI	BIT(3)	/* un-regular builtin (!special,!regular) */
#define FC_BI		(FC_SPECBI|FC_REGBI|FC_UNREGBI)
#define FC_PATH		BIT(4)	/* do path search */
#define FC_DEFPATH	BIT(5)	/* use default path in path search */


#define AF_ARGV_ALLOC	0x1	/* argv[] array allocated */
#define AF_ARGS_ALLOCED	0x2	/* argument strings allocated */
#define AI_ARGV(a, i)	((i) == 0 ? (a).argv[0] : (a).argv[(i) - (a).skip])
#define AI_ARGC(a)	((a).argc_ - (a).skip)

/* Argument info.  Used for $#, $* for shell, functions, includes, etc. */
struct arg_info {
	int flags;	/* AF_* */
	char **argv;
	int argc_;
	int skip;	/* first arg is argv[0], second is argv[1 + skip] */
};

/*
 * activation record for function blocks
 */
struct block {
	Area	area;		/* area to allocate things */
	/*struct arg_info argi;*/
	char	**argv;
	int	argc;
	int	flags;		/* see BF_* */
	struct	table vars;	/* local variables */
	struct	table funs;	/* local functions */
	Getopt	getopts_state;
	char *	error;		/* error handler */
	char *	exit;		/* exit handler */
	struct	block *next;	/* enclosing block */
};

/* Values for struct block.flags */
#define BF_DOGETOPTS	BIT(0)	/* save/restore getopts state */

/*
 * Used by twalk() and tnext() routines.
 */
struct tstate {
	int left;
	struct tbl **next;
};


EXTERN	struct table taliases;	/* tracked aliases */
EXTERN	struct table builtins;	/* built-in commands */
EXTERN	struct table aliases;	/* aliases */
EXTERN	struct table keywords;	/* keywords */
EXTERN	struct table homedirs;	/* homedir() cache */

struct builtin {
	const char   *name;
	int  (*func)(char **);
};

extern const struct builtin shbuiltins [], kshbuiltins [];

/* var spec values */
#define	V_NONE			0
#define	V_PATH			1
#define	V_IFS			2
#define	V_SECONDS		3
#define	V_OPTIND		4
#define	V_RANDOM		8
#define V_HISTSIZE		9
#define V_HISTFILE		10
#define V_COLUMNS		13
#define V_TMOUT			15
#define V_TMPDIR		16
#define V_LINENO		17

/* values for set_prompt() */
#define PS1	0		/* command */
#define PS2	1		/* command continuation */

EXTERN char *path;		/* copy of either PATH or def_path */
EXTERN const char *def_path;	/* path to use if PATH not set */
EXTERN char *tmpdir;		/* TMPDIR value */
EXTERN const char *prompt;
EXTERN int cur_prompt;		/* PS1 or PS2 */
EXTERN int current_lineno;	/* LINENO value */

#define	NOBLOCK	((struct op *)NULL)
#define	NOWORD	((char *)NULL)
#define	NOWORDS	((char **)NULL)

/*
 * Description of a command or an operation on commands.
 */
struct op {
	short	type;			/* operation type, see below */
	union { /* WARNING: newtp(), tcopy() use evalflags = 0 to clear union */
		short	evalflags;	/* TCOM: arg expansion eval() flags */
		short	ksh_func;	/* TFUNC: function x (vs x()) */
	} u;
	char  **args;			/* arguments to a command */
	char  **vars;			/* variable assignments */
	struct ioword	**ioact;	/* IO actions (eg, < > >>) */
	struct op *left, *right;	/* descendents */
	char   *str;			/* word for case; identifier for for,
					 * select, and functions;
					 * path to execute for TEXEC;
					 * time hook for TCOM.
					 */
	int	lineno;			/* TCOM/TFUNC: LINENO for this */
};

/* Tree.type values */
#define	TEOF		0
#define	TCOM		1	/* command */
#define	TPAREN		2	/* (c-list) */
#define	TPIPE		3	/* a | b */
#define	TLIST		4	/* a ; b */
#define	TOR		5	/* || */
#define	TAND		6	/* && */
#define TBANG		7	/* ! */
#define TDBRACKET	8	/* [[ .. ]] */
#define	TFOR		9
#define TSELECT		10
#define	TCASE		11
#define	TIF		12
#define	TWHILE		13
#define	TUNTIL		14
#define	TELIF		15
#define	TPAT		16	/* pattern in case */
#define	TBRACE		17	/* {c-list} */
#define	TASYNC		18	/* c & */
#define	TFUNCT		19	/* function name { command; } */
#define	TTIME		20	/* time pipeline */
#define	TEXEC		21	/* fork/exec eval'd TCOM */
#define TCOPROC		22	/* coprocess |& */

/*
 * prefix codes for words in command tree
 */
#define	EOS	0		/* end of string */
#define	CHAR	1		/* unquoted character */
#define	QCHAR	2		/* quoted character */
#define	COMSUB	3		/* $() substitution (0 terminated) */
#define EXPRSUB	4		/* $(()) substitution (0 terminated) */
#define	OQUOTE	5		/* opening " or ' */
#define	CQUOTE	6		/* closing " or ' */
#define	OSUBST	7		/* opening ${ subst (followed by { or X) */
#define	CSUBST	8		/* closing } of above (followed by } or X) */
#define OPAT	9		/* open pattern: *(, @(, etc. */
#define SPAT	10		/* separate pattern: | */
#define CPAT	11		/* close pattern: ) */

/*
 * IO redirection
 */
struct ioword {
	int	unit;	/* unit affected */
	int	flag;	/* action (below) */
	char	*name;	/* file name (unused if heredoc) */
	char	*delim;	/* delimiter for <<,<<- */
	char	*heredoc;/* content of heredoc */
};

/* ioword.flag - type of redirection */
#define	IOTYPE	0xF		/* type: bits 0:3 */
#define	IOREAD	0x1		/* < */
#define	IOWRITE	0x2		/* > */
#define	IORDWR	0x3		/* <>: todo */
#define	IOHERE	0x4		/* << (here file) */
#define	IOCAT	0x5		/* >> */
#define	IODUP	0x6		/* <&/>& */
#define	IOEVAL	BIT(4)		/* expand in << */
#define	IOSKIP	BIT(5)		/* <<-, skip ^\t* */
#define	IOCLOB	BIT(6)		/* >|, override -o noclobber */
#define IORDUP	BIT(7)		/* x<&y (as opposed to x>&y) */
#define IONAMEXP BIT(8)		/* name has been expanded */

/* execute/exchild flags */
#define	XEXEC	BIT(0)		/* execute without forking */
#define	XFORK	BIT(1)		/* fork before executing */
#define	XBGND	BIT(2)		/* command & */
#define	XPIPEI	BIT(3)		/* input is pipe */
#define	XPIPEO	BIT(4)		/* output is pipe */
#define	XPIPE	(XPIPEI|XPIPEO)	/* member of pipe */
#define	XXCOM	BIT(5)		/* `...` command */
#define	XPCLOSE	BIT(6)		/* exchild: close close_fd in parent */
#define	XCCLOSE	BIT(7)		/* exchild: close close_fd in child */
#define XERROK	BIT(8)		/* non-zero exit ok (for set -e) */
#define XCOPROC BIT(9)		/* starting a co-process */
#define XTIME	BIT(10)		/* timing TCOM command */

/*
 * flags to control expansion of words (assumed by t->evalflags to fit
 * in a short)
 */
#define	DOBLANK	BIT(0)		/* perform blank interpretation */
#define	DOGLOB	BIT(1)		/* expand [?* */
#define	DOPAT	BIT(2)		/* quote *?[ */
#define	DOTILDE	BIT(3)		/* normal ~ expansion (first char) */
#define DONTRUNCOMMAND BIT(4)	/* do not run $(command) things */
#define DOASNTILDE BIT(5)	/* assignment ~ expansion (after =, :) */
#define DOBRACE_ BIT(6)		/* used by expand(): do brace expansion */
#define DOMAGIC_ BIT(7)		/* used by expand(): string contains MAGIC */
#define DOTEMP_	BIT(8)		/* ditto : in word part of ${..[%#=?]..} */
#define DOVACHECK BIT(9)	/* var assign check (for typeset, set, etc) */
#define DOMARKDIRS BIT(10)	/* force markdirs behaviour */

/*
 * The arguments of [[ .. ]] expressions are kept in t->args[] and flags
 * indicating how the arguments have been munged are kept in t->vars[].
 * The contents of t->vars[] are stuffed strings (so they can be treated
 * like all other t->vars[]) in which the second character is the one that
 * is examined.  The DB_* defines are the values for these second characters.
 */
#define DB_NORM	1		/* normal argument */
#define DB_OR	2		/* || -> -o conversion */
#define DB_AND	3		/* && -> -a conversion */
#define DB_BE	4		/* an inserted -BE */
#define DB_PAT	5		/* a pattern argument */

#define X_EXTRA		8	/* this many extra bytes in X string */

typedef struct XString {
	char   *end, *beg;	/* end, begin of string */
	size_t	len;		/* length */
	Area	*areap;		/* area to allocate/free from */
} XString;

typedef char *XStringP;

/* initialize expandable string */
#define	Xinit(xs, xp, length, area) do { \
			(xs).len = length; \
			(xs).areap = (area); \
			(xs).beg = alloc((xs).len + X_EXTRA, (xs).areap); \
			(xs).end = (xs).beg + (xs).len; \
			xp = (xs).beg; \
		} while (0)

/* stuff char into string */
#define	Xput(xs, xp, c)	(*xp++ = (c))

/* check if there are at least n bytes left */
#define	XcheckN(xs, xp, n) do { \
		    int more = ((xp) + (n)) - (xs).end; \
		    if (more > 0) \
			xp = Xcheck_grow_(&xs, xp, more); \
		} while (0)

/* check for overflow, expand string */
#define Xcheck(xs, xp)	XcheckN(xs, xp, 1)

/* free string */
#define	Xfree(xs, xp)	afree((void*) (xs).beg, (xs).areap)

/* close, return string */
#define	Xclose(xs, xp)	(char*) aresize((void*)(xs).beg, \
					(size_t)((xp) - (xs).beg), (xs).areap)
/* begin of string */
#define	Xstring(xs, xp)	((xs).beg)

#define Xnleft(xs, xp) ((xs).end - (xp))	/* may be less than 0 */
#define	Xlength(xs, xp) ((xp) - (xs).beg)
#define Xsize(xs, xp) ((xs).end - (xs).beg)
#define	Xsavepos(xs, xp) ((xp) - (xs).beg)
#define	Xrestpos(xs, xp, n) ((xs).beg + (n))

char *	Xcheck_grow_(XString *, char *, unsigned);

/*
 * expandable vector of generic pointers
 */

typedef struct XPtrV {
	void  **cur;		/* next avail pointer */
	void  **beg, **end;	/* begin, end of vector */
} XPtrV;

#define	XPinit(x, n) do { \
			void **vp__; \
			vp__ = (void**) alloc(sizeofN(void*, n), ATEMP); \
			(x).cur = (x).beg = vp__; \
			(x).end = vp__ + n; \
		} while (0)

#define	XPput(x, p) do { \
			if ((x).cur >= (x).end) { \
				int n = XPsize(x); \
				(x).beg = (void**) aresize((void*) (x).beg, \
						   sizeofN(void*, n*2), ATEMP); \
				(x).cur = (x).beg + n; \
				(x).end = (x).cur + n; \
			} \
			*(x).cur++ = (p); \
		} while (0)

#define	XPptrv(x)	((x).beg)
#define	XPsize(x)	((x).cur - (x).beg)

#define	XPclose(x)	(void**) aresize((void*)(x).beg, \
					 sizeofN(void*, XPsize(x)), ATEMP)

#define	XPfree(x)	afree((void*) (x).beg, ATEMP)

#define	IDENT	64

typedef struct source Source;
struct source {
	const char *str;	/* input pointer */
	int	type;		/* input type */
	const char *start;	/* start of current buffer */
	union {
		char **strv;	/* string [] */
		struct shf *shf; /* shell file */
		struct tbl *tblp; /* alias (SALIAS) */
		char *freeme;	/* also for SREREAD */
	} u;
	char	ugbuf[2];	/* buffer for ungetsc() (SREREAD) and
				 * alias (SALIAS) */
	int	line;		/* line number */
	int	errline;	/* line the error occurred on (0 if not set) */
	const char *file;	/* input file name */
	int	flags;		/* SF_* */
	Area	*areap;
	XString	xs;		/* input buffer */
	Source *next;		/* stacked source */
};

/* Source.type values */
#define	SEOF		0	/* input EOF */
#define	SFILE		1	/* file input */
#define SSTDIN		2	/* read stdin */
#define	SSTRING		3	/* string */
#define	SWSTR		4	/* string without \n */
#define	SWORDS		5	/* string[] */
#define	SWORDSEP	6	/* string[] separator */
#define	SALIAS		7	/* alias expansion */
#define SREREAD		8	/* read ahead to be re-scanned */

/* Source.flags values */
#define SF_ECHO		BIT(0)	/* echo input to shlout */
#define SF_ALIAS	BIT(1)	/* faking space at end of alias */
#define SF_ALIASEND	BIT(2)	/* faking space at end of alias */
#define SF_TTY		BIT(3)	/* type == SSTDIN & it is a tty */

/*
 * states while lexing word
 */
#define	SBASE		0	/* outside any lexical constructs */
#define	SWORD		1	/* implicit quoting for substitute() */
#define	SLETPAREN	2	/* inside (( )), implicit quoting */
#define	SSQUOTE		3	/* inside '' */
#define	SDQUOTE		4	/* inside "" */
#define	SBRACE		5	/* inside ${} */
#define	SCSPAREN	6	/* inside $() */
#define	SBQUOTE		7	/* inside `` */
#define	SASPAREN	8	/* inside $(( )) */
#define SHEREDELIM	9	/* parsing <<,<<- delimiter */
#define SHEREDQUOTE	10	/* parsing " in <<,<<- delimiter */
#define SPATTERN	11	/* parsing *(...|...) pattern (*+?@!) */
#define STBRACE		12	/* parsing ${..[#%]..} */

typedef union {
	int	i;
	char   *cp;
	char  **wp;
	struct op *o;
	struct ioword *iop;
} YYSTYPE;

/* If something is added here, add it to tokentab[] in syn.c as well */
#define	LWORD		256
#define	LOGAND		257	/* && */
#define	LOGOR		258	/* || */
#define	BREAK		259	/* ;; */
#define	IF		260
#define	THEN		261
#define	ELSE		262
#define	ELIF		263
#define	FI		264
#define	CASE		265
#define	ESAC		266
#define	FOR		267
#define SELECT		268
#define	WHILE		269
#define	UNTIL		270
#define	DO		271
#define	DONE		272
#define	IN		273
#define	FUNCTION	274
#define	TIME		275
#define	REDIR		276
#define MDPAREN		277	/* (( )) */
#define BANG		278	/* ! */
#define DBRACKET	279	/* [[ .. ]] */
#define COPROC		280	/* |& */
#define	YYERRCODE	300

/* flags to yylex */
#define	CONTIN		BIT(0)	/* skip new lines to complete command */
#define	ONEWORD		BIT(1)	/* single word for substitute() */
#define	ALIAS		BIT(2)	/* recognize alias */
#define	KEYWORD		BIT(3)	/* recognize keywords */
#define LETEXPR		BIT(4)	/* get expression inside (( )) */
#define VARASN		BIT(5)	/* check for var=word */
#define ARRAYVAR	BIT(6)	/* parse x[1 & 2] as one word */
#define ESACONLY	BIT(7)	/* only accept esac keyword */
#define CMDWORD		BIT(8)	/* parsing simple command (alias related) */
#define HEREDELIM	BIT(9)	/* parsing <<,<<- delimiter */
#define	LQCHAR		BIT(10)	/* source string contains QCHAR */
#define	HEREDOC		BIT(11)	/* parsing a here document */

#define	HERES	10		/* max << in line */

EXTERN	Source *source;		/* yyparse/yylex source */
EXTERN	YYSTYPE	yylval;		/* result from yylex */
EXTERN	struct ioword *heres [HERES], **herep;
EXTERN	char	ident [IDENT+1];

#define HISTORYSIZE	500	/* size of saved history */

EXTERN	char  **history;	/* saved commands */
EXTERN	char  **histptr;	/* last history item */
EXTERN	int	histsize;	/* history size */

/* alloc.c */
Area *	ainit(Area *);
void	afreeall(Area *);
void *	alloc(size_t, Area *);
void *	aresize(void *, size_t, Area *);
void	afree(void *, Area *);
/* edit.c */
void	x_init(void);
int	x_read(char *, size_t);
int	x_bind(const char *, const char *, int, int);
/* eval.c */
char *	substitute(const char *, int);
char **	eval(char **, int);
char *	evalstr(char *cp, int);
char *	evalonestr(char *cp, int);
char	*debunk(char *, const char *, size_t);
void	expand(char *, XPtrV *, int);
int	glob_str(char *, XPtrV *, int);
/* exec.c */
int	execute(struct op * volatile, volatile int);
int	shcomexec(char **);
struct tbl * findfunc(const char *, unsigned int, int);
int	define(const char *, struct op *);
void	builtin(const char *, int (*)(char **));
struct tbl *	findcom(const char *, int);
void	flushcom(int);
char *	search(const char *, const char *, int, int *);
int	search_access(const char *, int, int *);
int	pr_menu(char *const *);
int	pr_list(char *const *);
/* expr.c */
int	evaluate(const char *, long *, int, bool);
int	v_evaluate(struct tbl *, const char *, volatile int, bool);
/* funcs.c */
int	c_hash(char **);
int	c_cd(char **);
int	c_pwd(char **);
int	c_print(char **);
int	c_whence(char **);
int	c_command(char **);
int	c_typeset(char **);
int	c_alias(char **);
int	c_unalias(char **);
int	c_let(char **);
int	c_jobs(char **);
int	c_fgbg(char **);
int	c_kill(char **);
void	getopts_reset(int);
int	c_getopts(char **);
int	c_bind(char **);
int	c_label(char **);
int	c_shift(char **);
int	c_umask(char **);
int	c_dot(char **);
int	c_wait(char **);
int	c_read(char **);
int	c_eval(char **);
int	c_trap(char **);
int	c_brkcont(char **);
int	c_exitreturn(char **);
int	c_set(char **);
int	c_unset(char **);
int	c_ulimit(char **);
int	c_times(char **);
int	timex(struct op *, int);
void	timex_hook(struct op *, char ** volatile *);
int	c_exec(char **);
int	c_builtin(char **);
int	c_test(char **);
/* histrap.c */
void	init_histvec(void);
void	hist_init(Source *);
void	hist_finish(void);
void	histsave(int, const char *, int);
int	c_fc(char **);
void	sethistsize(int);
void	sethistfile(const char *);
char **	histpos(void);
int	histN(void);
int	histnum(int);
int	findhist(int, int, const char *, int);
int	findhistrel(const char *);
char  **hist_get_newest(int);
void	inittraps(void);
void	alarm_init(void);
Trap *	gettrap(const char *, int);
void	trapsig(int);
void	intrcheck(void);
int	fatal_trap_check(void);
int	trap_pending(void);
void	runtraps(int intr);
void	runtrap(Trap *);
void	cleartraps(void);
void	restoresigs(void);
void	settrap(Trap *, char *);
int	block_pipe(void);
void	restore_pipe(int);
int	setsig(Trap *, sig_t, int);
void	setexecsig(Trap *, int);
/* jobs.c */
void	j_init(int);
void	j_exit(void);
void	j_change(void);
int	exchild(struct op *, int, int);
void	startlast(void);
int	waitlast(void);
int	waitfor(const char *, int *);
int	j_kill(const char *, int);
int	j_resume(const char *, int);
int	j_jobs(const char *, int, int);
int	j_njobs(void);
void	j_notify(void);
pid_t	j_async(void);
int	j_stopped_running(void);
/* lex.c */
int	yylex(int);
void	yyerror(const char *, ...)
	    __attribute__((__noreturn__, __format__ (printf, 1, 2)));
Source * pushs(int, Area *);
void	set_prompt(int, Source *);
void	pprompt(const char *, int);
/* main.c */
int	include(const char *, int, char **, int);
int	command(const char *);
int	shell(Source *volatile, int volatile);
void	unwind(int) __attribute__((__noreturn__));
void	newenv(int);
void	quitenv(struct shf *);
void	cleanup_parents_env(void);
void	cleanup_proc_env(void);
void	aerror(Area *, const char *) __attribute__((__noreturn__));
void	errorf(const char *, ...)
	    __attribute__((__noreturn__, __format__ (printf, 1, 2)));
void	warningf(int, const char *, ...)
	    __attribute__((__format__ (printf, 2, 3)));
void	bi_errorf(const char *, ...)
	    __attribute__((__format__ (printf, 1, 2)));
void	internal_errorf(int, const char *, ...)
	    __attribute__((__format__ (printf, 2, 3)));
void	error_prefix(int);
void	shellf(const char *, ...)
	    __attribute__((__format__ (printf, 1, 2)));
void	shprintf(const char *, ...)
	    __attribute__((__format__ (printf, 1, 2)));
int	can_seek(int);
void	initio(void);
int	ksh_dup2(int, int, int);
int	savefd(int, int);
void	restfd(int, int);
void	openpipe(int *);
void	closepipe(int *);
int	check_fd(char *, int, const char **);
void	coproc_init(void);
void	coproc_read_close(int);
void	coproc_readw_close(int);
void	coproc_write_close(int);
int	coproc_getfd(int, const char **);
void	coproc_cleanup(int);
struct temp *maketemp(Area *, Temp_type, struct temp **);
unsigned int	hash(const char *);
void		tinit(struct table *, Area *, int);
struct tbl *	tsearch(struct table *, const char *, unsigned int);
struct tbl *	tenter(struct table *, const char *, unsigned int);
void		tdelete(struct tbl *);
void		twalk(struct tstate *, struct table *);
struct tbl *	tnext(struct tstate *);
struct tbl **	tsort(struct table *);
/* misc.c */
void	setctypes(const char *, int);
void	initctypes(void);
char *	ulton(unsigned long, int);
char *	str_save(const char *, Area *);
char *	str_nsave(const char *, int, Area *);
int	option(const char *);
char *	getoptions(void);
void	change_flag(enum sh_flag, int, int);
int	parse_args(char **, int, int *);
int	getn(const char *, int *);
int	bi_getn(const char *, int *);
int	gmatchx(const char *, const char *, int);
int	has_globbing(const char *, const char *);
const unsigned char *pat_scan(const unsigned char *, const unsigned char *,
    int);
void	qsortp(void **, size_t, int (*)(void *, void *));
int	xstrcmp(void *, void *);
void	ksh_getopt_reset(Getopt *, int);
int	ksh_getopt(char **, Getopt *, const char *);
void	print_value_quoted(const char *);
void	print_columns(struct shf *, int, char *(*)(void *, int, char *, int),
    void *, int, int prefcol);
int	strip_nuls(char *, int);
int	blocking_read(int, char *, int);
int	reset_nonblock(int);
char	*ksh_get_wd(char *, int);
int	make_path(const char *, const char *, char **, XString *, int *);
void	simplify_path(char *);
char	*get_phys_path(const char *);
void	set_current_wd(char *);
/* shf.c */
struct shf *shf_open(const char *, int, int, int);
struct shf *shf_fdopen(int, int, struct shf *);
struct shf *shf_reopen(int, int, struct shf *);
struct shf *shf_sopen(char *, int, int, struct shf *);
int	shf_close(struct shf *);
int	shf_fdclose(struct shf *);
char *	shf_sclose(struct shf *);
int	shf_finish(struct shf *);
int	shf_flush(struct shf *);
int	shf_seek(struct shf *, off_t, int);
int	shf_read(char *, int, struct shf *);
char *	shf_getse(char *, int, struct shf *);
int	shf_getchar(struct shf *s);
int	shf_ungetc(int, struct shf *);
int	shf_putchar(int, struct shf *);
int	shf_puts(const char *, struct shf *);
int	shf_write(const char *, int, struct shf *);
int	shf_fprintf(struct shf *, const char *, ...);
int	shf_snprintf(char *, int, const char *, ...);
char *	shf_smprintf(const char *, ...);
int	shf_vfprintf(struct shf *, const char *, va_list);
/* syn.c */
void	initkeywords(void);
struct op * compile(Source *);
/* tree.c */
int	fptreef(struct shf *, int, const char *, ...);
char *	snptreef(char *, int, const char *, ...);
struct op *	tcopy(struct op *, Area *);
char *	wdcopy(const char *, Area *);
char *	wdscan(const char *, int);
char *	wdstrip(const char *);
void	tfree(struct op *, Area *);
/* var.c */
void	newblock(void);
void	popblock(void);
void	initvar(void);
struct tbl *	global(const char *);
struct tbl *	local(const char *, bool);
char *	str_val(struct tbl *);
long	intval(struct tbl *);
int	setstr(struct tbl *, const char *, int);
struct tbl *setint_v(struct tbl *, struct tbl *, bool);
void	setint(struct tbl *, long);
int	getint(struct tbl *, long *, bool);
struct tbl *	typeset(const char *, Tflag, Tflag, int, int);
void	unset(struct tbl *, int);
char  * skip_varname(const char *, int);
char	*skip_wdvarname(const char *, int);
int	is_wdvarname(const char *, int);
int	is_wdvarassign(const char *);
char **	makenv(void);
void	change_random(void);
int	array_ref_len(const char *);
char *	arrayname(const char *);
void    set_array(const char *, int, char **);
int	eaccess(const char *, int);

enum Test_op {
	TO_NONOP = 0,	/* non-operator */
	/* unary operators */
	TO_STNZE, TO_STZER, TO_OPTION,
	TO_FILAXST,
	TO_FILEXST,
	TO_FILREG, TO_FILBDEV, TO_FILCDEV, TO_FILSYM, TO_FILFIFO, TO_FILSOCK,
	TO_FILCDF, TO_FILID, TO_FILGID, TO_FILSETG, TO_FILSTCK, TO_FILUID,
	TO_FILRD, TO_FILGZ, TO_FILTT, TO_FILSETU, TO_FILWR, TO_FILEX,
	/* binary operators */
	TO_STEQL, TO_STNEQ, TO_STLT, TO_STGT, TO_INTEQ, TO_INTNE, TO_INTGT,
	TO_INTGE, TO_INTLT, TO_INTLE, TO_FILEQ, TO_FILNT, TO_FILOT
};
typedef enum Test_op Test_op;

/* Used by Test_env.isa() (order important - used to index *_tokens[] arrays) */
enum Test_meta {
	TM_OR,		/* -o or || */
	TM_AND,		/* -a or && */
	TM_NOT,		/* ! */
	TM_OPAREN,	/* ( */
	TM_CPAREN,	/* ) */
	TM_UNOP,	/* unary operator */
	TM_BINOP,	/* binary operator */
	TM_END		/* end of input */
};
typedef enum Test_meta Test_meta;

#define TEF_ERROR	BIT(0)		/* set if we've hit an error */
#define TEF_DBRACKET	BIT(1)		/* set if [[ .. ]] test */

typedef struct test_env Test_env;
struct test_env {
	int	flags;		/* TEF_* */
	union {
		char	**wp;		/* used by ptest_* */
		XPtrV	*av;		/* used by dbtestp_* */
	} pos;
	char **wp_end;			/* used by ptest_* */
	int	(*isa)(Test_env *, Test_meta);
	const char *(*getopnd) (Test_env *, Test_op, int);
	int	(*eval)(Test_env *, Test_op, const char *, const char *, int);
	void	(*error)(Test_env *, int, const char *);
};

Test_op	test_isop(Test_meta, const char *);
int     test_eval(Test_env *, Test_op, const char *, const char *, int);
int	test_parse(Test_env *);

EXTERN int		tty_fd I__(-1);	/* dup'd tty file descriptor */
EXTERN int		tty_devtty;	/* true if tty_fd is from /dev/tty */
EXTERN struct termios	tty_state;	/* saved tty state */

extern void	tty_init(int);
extern void	tty_close(void);

/* be sure not to interfere with anyone else's idea about EXTERN */
#ifdef EXTERN_DEFINED
# undef EXTERN_DEFINED
# undef EXTERN
#endif
#undef I__

#ifndef HAVE_ARC4RANDOM
#if defined(__gnu_linux__) || defined(__INTERIX) || defined(__sun__) \
    || (defined(__NetBSD__) && (__NetBSD_Version__ < 106020000)) \
    || defined(__CYGWIN__)
#define	HAVE_ARC4RANDOM	0
#else
#define	HAVE_ARC4RANDOM	1
#endif
#endif