sh.h revision 1.74
1/*	$OpenBSD: sh.h,v 1.74 2018/11/20 07:02:23 martijn Exp $	*/
2
3/*
4 * Public Domain Bourne/Korn shell
5 */
6
7/* $From: sh.h,v 1.2 1994/05/19 18:32:40 michael Exp michael $ */
8
9#include "config.h"	/* system and option configuration info */
10
11/* Start of common headers */
12
13#include <limits.h>
14#include <setjmp.h>
15#include <stdarg.h>
16#include <stddef.h>
17#include <signal.h>
18#include <stdbool.h>
19
20/* end of common headers */
21
22#define	NELEM(a) (sizeof(a) / sizeof((a)[0]))
23#define	BIT(i)	(1<<(i))	/* define bit in flag */
24
25#define	NUFILE	32		/* Number of user-accessible files */
26#define	FDBASE	10		/* First file usable by Shell */
27
28#define BITS(t)	(CHAR_BIT * sizeof(t))
29
30/* Make MAGIC a char that might be printed to make bugs more obvious, but
31 * not a char that is used often.  Also, can't use the high bit as it causes
32 * portability problems (calling strchr(x, 0x80|'x') is error prone).
33 */
34#define	MAGIC		(7)	/* prefix for *?[!{,} during expand */
35#define ISMAGIC(c)	((unsigned char)(c) == MAGIC)
36
37#define	LINE	4096		/* input line size */
38
39extern	const char *kshname;	/* $0 */
40extern	pid_t	kshpid;		/* $$, shell pid */
41extern	pid_t	procpid;	/* pid of executing process */
42extern	uid_t	ksheuid;	/* effective uid of shell */
43extern	int	exstat;		/* exit status */
44extern	int	subst_exstat;	/* exit status of last $(..)/`..` */
45extern	const char *safe_prompt; /* safe prompt if PS1 substitution fails */
46extern	char	username[];	/* username for \u prompt expansion */
47
48/*
49 * Area-based allocation built on malloc/free
50 */
51typedef struct Area {
52	struct link *freelist;	/* free list */
53} Area;
54
55extern	Area	aperm;		/* permanent object space */
56#define	APERM	&aperm
57#define	ATEMP	&genv->area
58
59#ifdef KSH_DEBUG
60# define kshdebug_init()	kshdebug_init_()
61# define kshdebug_printf(a)	kshdebug_printf_ a
62# define kshdebug_dump(a)	kshdebug_dump_ a
63#else /* KSH_DEBUG */
64# define kshdebug_init()
65# define kshdebug_printf(a)
66# define kshdebug_dump(a)
67#endif /* KSH_DEBUG */
68
69/*
70 * parsing & execution environment
71 */
72struct env {
73	short	type;			/* environment type - see below */
74	short	flags;			/* EF_* */
75	Area	area;			/* temporary allocation area */
76	struct	block *loc;		/* local variables and functions */
77	short  *savefd;			/* original redirected fd's */
78	struct	env *oenv;		/* link to previous environment */
79	sigjmp_buf jbuf;		/* long jump back to env creator */
80	struct temp *temps;		/* temp files */
81};
82extern	struct env	*genv;
83
84/* struct env.type values */
85#define	E_NONE	0		/* dummy environment */
86#define	E_PARSE	1		/* parsing command # */
87#define	E_FUNC	2		/* executing function # */
88#define	E_INCL	3		/* including a file via . # */
89#define	E_EXEC	4		/* executing command tree */
90#define	E_LOOP	5		/* executing for/while # */
91#define	E_ERRH	6		/* general error handler # */
92/* # indicates env has valid jbuf (see unwind()) */
93
94/* struct env.flag values */
95#define EF_FUNC_PARSE	BIT(0)	/* function being parsed */
96#define EF_BRKCONT_PASS	BIT(1)	/* set if E_LOOP must pass break/continue on */
97#define EF_FAKE_SIGDIE	BIT(2)	/* hack to get info from unwind to quitenv */
98
99/* Do breaks/continues stop at env type e? */
100#define STOP_BRKCONT(t)	((t) == E_NONE || (t) == E_PARSE \
101			 || (t) == E_FUNC || (t) == E_INCL)
102/* Do returns stop at env type e? */
103#define STOP_RETURN(t)	((t) == E_FUNC || (t) == E_INCL)
104
105/* values for siglongjmp(e->jbuf, 0) */
106#define LRETURN	1		/* return statement */
107#define	LEXIT	2		/* exit statement */
108#define LERROR	3		/* errorf() called */
109#define LLEAVE	4		/* untrappable exit/error */
110#define LINTR	5		/* ^C noticed */
111#define	LBREAK	6		/* break statement */
112#define	LCONTIN	7		/* continue statement */
113#define LSHELL	8		/* return to interactive shell() */
114#define LAEXPR	9		/* error in arithmetic expression */
115
116/* option processing */
117#define OF_CMDLINE	0x01	/* command line */
118#define OF_SET		0x02	/* set builtin */
119#define OF_SPECIAL	0x04	/* a special variable changing */
120#define OF_INTERNAL	0x08	/* set internally by shell */
121#define OF_ANY		(OF_CMDLINE | OF_SET | OF_SPECIAL | OF_INTERNAL)
122
123struct option {
124    const char	*name;	/* long name of option */
125    char	c;	/* character flag (if any) */
126    short	flags;	/* OF_* */
127};
128extern const struct option sh_options[];
129
130/*
131 * flags (the order of these enums MUST match the order in misc.c(options[]))
132 */
133enum sh_flag {
134	FEXPORT = 0,	/* -a: export all */
135	FBRACEEXPAND,	/* enable {} globbing */
136	FBGNICE,	/* bgnice */
137	FCOMMAND,	/* -c: (invocation) execute specified command */
138	FCSHHISTORY,	/* csh-style history enabled */
139#ifdef EMACS
140	FEMACS,		/* emacs command editing */
141#endif
142	FERREXIT,	/* -e: quit on error */
143#ifdef EMACS
144	FGMACS,		/* gmacs command editing */
145#endif
146	FIGNOREEOF,	/* eof does not exit */
147	FTALKING,	/* -i: interactive */
148	FKEYWORD,	/* -k: name=value anywhere */
149	FLOGIN,		/* -l: a login shell */
150	FMARKDIRS,	/* mark dirs with / in file name completion */
151	FMONITOR,	/* -m: job control monitoring */
152	FNOCLOBBER,	/* -C: don't overwrite existing files */
153	FNOEXEC,	/* -n: don't execute any commands */
154	FNOGLOB,	/* -f: don't do file globbing */
155	FNOHUP,		/* -H: don't kill running jobs when login shell exits */
156	FNOLOG,		/* don't save functions in history (ignored) */
157	FNOTIFY,	/* -b: asynchronous job completion notification */
158	FNOUNSET,	/* -u: using an unset var is an error */
159	FPHYSICAL,	/* -o physical: don't do logical cd's/pwd's */
160	FPOSIX,		/* -o posix: be posixly correct */
161	FPRIVILEGED,	/* -p: use suid_profile */
162	FRESTRICTED,	/* -r: restricted shell */
163	FSH,		/* -o sh: favor sh behaviour */
164	FSTDIN,		/* -s: (invocation) parse stdin */
165	FTRACKALL,	/* -h: create tracked aliases for all commands */
166	FVERBOSE,	/* -v: echo input */
167#ifdef VI
168	FVI,		/* vi command editing */
169	FVIRAW,		/* always read in raw mode (ignored) */
170	FVISHOW8,	/* display chars with 8th bit set as is (versus M-) */
171	FVITABCOMPLETE,	/* enable tab as file name completion char */
172	FVIESCCOMPLETE,	/* enable ESC as file name completion in command mode */
173#endif
174	FXTRACE,	/* -x: execution trace */
175	FTALKING_I,	/* (internal): initial shell was interactive */
176	FNFLAGS /* (place holder: how many flags are there) */
177};
178
179#define Flag(f)	(shell_flags[(int) (f)])
180
181extern	char shell_flags[FNFLAGS];
182
183extern	char	null[];	/* null value for variable */
184
185enum temp_type {
186	TT_HEREDOC_EXP,	/* expanded heredoc */
187	TT_HIST_EDIT	/* temp file used for history editing (fc -e) */
188};
189typedef enum temp_type Temp_type;
190/* temp/heredoc files.  The file is removed when the struct is freed. */
191struct temp {
192	struct temp	*next;
193	struct shf	*shf;
194	int		pid;		/* pid of process parsed here-doc */
195	Temp_type	type;
196	char		*name;
197};
198
199/*
200 * stdio and our IO routines
201 */
202
203#define shl_spare	(&shf_iob[0])	/* for c_read()/c_print() */
204#define shl_stdout	(&shf_iob[1])
205#define shl_out		(&shf_iob[2])
206extern int shl_stdout_ok;
207
208/*
209 * trap handlers
210 */
211typedef struct trap {
212	int	signal;		/* signal number */
213	const char *name;	/* short name */
214	const char *mess;	/* descriptive name */
215	char   *trap;		/* trap command */
216	volatile sig_atomic_t set; /* trap pending */
217	int	flags;		/* TF_* */
218	sig_t cursig;		/* current handler (valid if TF_ORIG_* set) */
219	sig_t shtrap;		/* shell signal handler */
220} Trap;
221
222/* values for Trap.flags */
223#define TF_SHELL_USES	BIT(0)	/* shell uses signal, user can't change */
224#define TF_USER_SET	BIT(1)	/* user has (tried to) set trap */
225#define TF_ORIG_IGN	BIT(2)	/* original action was SIG_IGN */
226#define TF_ORIG_DFL	BIT(3)	/* original action was SIG_DFL */
227#define TF_EXEC_IGN	BIT(4)	/* restore SIG_IGN just before exec */
228#define TF_EXEC_DFL	BIT(5)	/* restore SIG_DFL just before exec */
229#define TF_DFL_INTR	BIT(6)	/* when received, default action is LINTR */
230#define TF_TTY_INTR	BIT(7)	/* tty generated signal (see j_waitj) */
231#define TF_CHANGED	BIT(8)	/* used by runtrap() to detect trap changes */
232#define TF_FATAL	BIT(9)	/* causes termination if not trapped */
233
234/* values for setsig()/setexecsig() flags argument */
235#define SS_RESTORE_MASK	0x3	/* how to restore a signal before an exec() */
236#define SS_RESTORE_CURR	0	/* leave current handler in place */
237#define SS_RESTORE_ORIG	1	/* restore original handler */
238#define SS_RESTORE_DFL	2	/* restore to SIG_DFL */
239#define SS_RESTORE_IGN	3	/* restore to SIG_IGN */
240#define SS_FORCE	BIT(3)	/* set signal even if original signal ignored */
241#define SS_USER		BIT(4)	/* user is doing the set (ie, trap command) */
242#define SS_SHTRAP	BIT(5)	/* trap for internal use (CHLD,ALRM,WINCH) */
243
244#define SIGEXIT_	0	/* for trap EXIT */
245#define SIGERR_		NSIG	/* for trap ERR */
246
247extern	volatile sig_atomic_t trap;	/* traps pending? */
248extern	volatile sig_atomic_t intrsig;	/* pending trap interrupts command */
249extern	volatile sig_atomic_t fatal_trap;	/* received a fatal signal */
250extern	volatile sig_atomic_t got_sigwinch;
251extern	Trap	sigtraps[NSIG+1];
252
253/*
254 * TMOUT support
255 */
256/* values for ksh_tmout_state */
257enum tmout_enum {
258	TMOUT_EXECUTING	= 0,	/* executing commands */
259	TMOUT_READING,		/* waiting for input */
260	TMOUT_LEAVING		/* have timed out */
261};
262extern unsigned int ksh_tmout;
263extern enum tmout_enum ksh_tmout_state;
264
265/* For "You have stopped jobs" message */
266extern int really_exit;
267
268/*
269 * fast character classes
270 */
271#define	C_ALPHA	 BIT(0)		/* a-z_A-Z */
272/* was	C_DIGIT */
273#define	C_LEX1	 BIT(2)		/* \0 \t\n|&;<>() */
274#define	C_VAR1	 BIT(3)		/* *@#!$-? */
275#define	C_IFSWS	 BIT(4)		/* \t \n (IFS white space) */
276#define	C_SUBOP1 BIT(5)		/* "=-+?" */
277#define	C_SUBOP2 BIT(6)		/* "#%" */
278#define	C_IFS	 BIT(7)		/* $IFS */
279#define	C_QUOTE	 BIT(8)		/*  \n\t"#$&'()*;<>?[\`| (needing quoting) */
280
281extern	short ctypes [];
282
283#define	ctype(c, t)	!!(ctypes[(unsigned char)(c)]&(t))
284#define	letter(c)	ctype(c, C_ALPHA)
285#define	digit(c)	isdigit((unsigned char)(c))
286#define	letnum(c)	(ctype(c, C_ALPHA) || isdigit((unsigned char)(c)))
287
288extern int ifs0;	/* for "$*" */
289
290/* Argument parsing for built-in commands and getopts command */
291
292/* Values for Getopt.flags */
293#define GF_ERROR	BIT(0)	/* call errorf() if there is an error */
294#define GF_PLUSOPT	BIT(1)	/* allow +c as an option */
295#define GF_NONAME	BIT(2)	/* don't print argv[0] in errors */
296
297/* Values for Getopt.info */
298#define GI_MINUS	BIT(0)	/* an option started with -... */
299#define GI_PLUS		BIT(1)	/* an option started with +... */
300#define GI_MINUSMINUS	BIT(2)	/* arguments were ended with -- */
301
302typedef struct {
303	int		optind;
304	int		uoptind;/* what user sees in $OPTIND */
305	char		*optarg;
306	int		flags;	/* see GF_* */
307	int		info;	/* see GI_* */
308	unsigned int	p;	/* 0 or index into argv[optind - 1] */
309	char		buf[2];	/* for bad option OPTARG value */
310} Getopt;
311
312extern Getopt builtin_opt;	/* for shell builtin commands */
313extern Getopt user_opt;		/* parsing state for getopts builtin command */
314
315/* This for co-processes */
316
317typedef int Coproc_id; /* something that won't (realistically) wrap */
318struct coproc {
319	int	read;		/* pipe from co-process's stdout */
320	int	readw;		/* other side of read (saved temporarily) */
321	int	write;		/* pipe to co-process's stdin */
322	Coproc_id id;		/* id of current output pipe */
323	int	njobs;		/* number of live jobs using output pipe */
324	void	*job;		/* 0 or job of co-process using input pipe */
325};
326extern struct coproc coproc;
327
328/* Used in jobs.c and by coprocess stuff in exec.c */
329extern sigset_t		sm_default, sm_sigchld;
330
331extern const char ksh_version[];
332
333/* name of called builtin function (used by error functions) */
334extern char	*builtin_argv0;
335extern int	builtin_flag;	/* flags of called builtin (SPEC_BI, etc.) */
336
337/* current working directory, and size of memory allocated for same */
338extern char	*current_wd;
339extern int	current_wd_size;
340
341/* Minimum required space to work with on a line - if the prompt leaves less
342 * space than this on a line, the prompt is truncated.
343 */
344#define MIN_EDIT_SPACE	7
345/* Minimum allowed value for x_cols: 2 for prompt, 3 for " < " at end of line
346 */
347#define MIN_COLS	(2 + MIN_EDIT_SPACE + 3)
348extern	int	x_cols;	/* tty columns */
349
350/* These to avoid bracket matching problems */
351#define OPAREN	'('
352#define CPAREN	')'
353#define OBRACK	'['
354#define CBRACK	']'
355#define OBRACE	'{'
356#define CBRACE	'}'
357
358/* Determine the location of the system (common) profile */
359#define KSH_SYSTEM_PROFILE "/etc/profile"
360
361/* Used by v_evaluate() and setstr() to control action when error occurs */
362#define KSH_UNWIND_ERROR	0x0	/* unwind the stack (longjmp) */
363#define KSH_RETURN_ERROR	0x1	/* return 1/0 for success/failure */
364#define KSH_IGNORE_RDONLY	0x4	/* ignore the read-only flag */
365
366#include "shf.h"
367#include "table.h"
368#include "tree.h"
369#include "expand.h"
370#include "lex.h"
371
372/* alloc.c */
373Area *	ainit(Area *);
374void	afreeall(Area *);
375void *	alloc(size_t, Area *);
376void *	areallocarray(void *, size_t, size_t, Area *);
377void *	aresize(void *, size_t, Area *);
378void	afree(void *, Area *);
379/* c_ksh.c */
380int	c_cd(char **);
381int	c_pwd(char **);
382int	c_print(char **);
383int	c_whence(char **);
384int	c_command(char **);
385int	c_type(char **);
386int	c_typeset(char **);
387int	c_alias(char **);
388int	c_unalias(char **);
389int	c_let(char **);
390int	c_jobs(char **);
391int	c_fgbg(char **);
392int	c_kill(char **);
393void	getopts_reset(int);
394int	c_getopts(char **);
395int	c_bind(char **);
396/* c_sh.c */
397int	c_label(char **);
398int	c_shift(char **);
399int	c_umask(char **);
400int	c_dot(char **);
401int	c_wait(char **);
402int	c_read(char **);
403int	c_eval(char **);
404int	c_trap(char **);
405int	c_brkcont(char **);
406int	c_exitreturn(char **);
407int	c_set(char **);
408int	c_unset(char **);
409int	c_ulimit(char **);
410int	c_times(char **);
411int	timex(struct op *, int, volatile int *);
412void	timex_hook(struct op *, char ** volatile *);
413int	c_exec(char **);
414int	c_builtin(char **);
415/* c_test.c */
416int	c_test(char **);
417/* edit.c: most prototypes in edit.h */
418void	x_init(void);
419int	x_read(char *, size_t);
420void	set_editmode(const char *);
421/* emacs.c: most prototypes in edit.h */
422int	x_bind(const char *, const char *, int, int);
423/* eval.c */
424char *	substitute(const char *, int);
425char **	eval(char **, int);
426char *	evalstr(char *cp, int);
427char *	evalonestr(char *cp, int);
428char	*debunk(char *, const char *, size_t);
429void	expand(char *, XPtrV *, int);
430int	glob_str(char *, XPtrV *, int);
431/* exec.c */
432int	execute(struct op * volatile, volatile int, volatile int *);
433int	shcomexec(char **);
434struct tbl * findfunc(const char *, unsigned int, int);
435int	define(const char *, struct op *);
436void	builtin(const char *, int (*)(char **));
437struct tbl *	findcom(const char *, int);
438void	flushcom(int);
439char *	search(const char *, const char *, int, int *);
440int	search_access(const char *, int, int *);
441int	pr_menu(char *const *);
442int	pr_list(char *const *);
443/* expr.c */
444int	evaluate(const char *, int64_t *, int, bool);
445int	v_evaluate(struct tbl *, const char *, volatile int, bool);
446/* history.c */
447void	init_histvec(void);
448void	hist_init(Source *);
449void	hist_finish(void);
450void	histsave(int, const char *, int);
451int	c_fc(char **);
452void	c_fc_reset(void);
453void	sethistcontrol(const char *);
454void	sethistsize(int);
455void	sethistfile(const char *);
456char **	histpos(void);
457int	histnum(int);
458int	findhist(int, int, const char *, int);
459int	findhistrel(const char *);
460char  **hist_get_newest(int);
461
462/* io.c */
463void	errorf(const char *, ...)
464	    __attribute__((__noreturn__, __format__ (printf, 1, 2)));
465void	warningf(bool, const char *, ...)
466	    __attribute__((__format__ (printf, 2, 3)));
467void	bi_errorf(const char *, ...)
468	    __attribute__((__format__ (printf, 1, 2)));
469void	internal_errorf(const char *, ...)
470	    __attribute__((__noreturn__, __format__ (printf, 1, 2)));
471void	internal_warningf(const char *, ...)
472	    __attribute__((__format__ (printf, 1, 2)));
473void	error_prefix(int);
474void	shellf(const char *, ...)
475	    __attribute__((__format__ (printf, 1, 2)));
476void	shprintf(const char *, ...)
477	    __attribute__((__format__ (printf, 1, 2)));
478#ifdef KSH_DEBUG
479void	kshdebug_init_(void);
480void	kshdebug_printf_(const char *, ...)
481	    __attribute__((__format__ (printf, 1, 2)));
482void	kshdebug_dump_(const char *, const void *, int);
483#endif /* KSH_DEBUG */
484int	can_seek(int);
485void	initio(void);
486int	ksh_dup2(int, int, int);
487int	savefd(int);
488void	restfd(int, int);
489void	openpipe(int *);
490void	closepipe(int *);
491int	check_fd(char *, int, const char **);
492void	coproc_init(void);
493void	coproc_read_close(int);
494void	coproc_readw_close(int);
495void	coproc_write_close(int);
496int	coproc_getfd(int, const char **);
497void	coproc_cleanup(int);
498struct temp *maketemp(Area *, Temp_type, struct temp **);
499/* jobs.c */
500void	j_init(int);
501void	j_suspend(void);
502void	j_exit(void);
503void	j_change(void);
504int	exchild(struct op *, int, volatile int *, int);
505void	startlast(void);
506int	waitlast(void);
507int	waitfor(const char *, int *);
508int	j_kill(const char *, int);
509int	j_resume(const char *, int);
510int	j_jobs(const char *, int, int);
511int	j_njobs(void);
512void	j_notify(void);
513pid_t	j_async(void);
514int	j_stopped_running(void);
515/* mail.c */
516void	mcheck(void);
517void	mcset(int64_t);
518void	mbset(char *);
519void	mpset(char *);
520/* main.c */
521int	include(const char *, int, char **, int);
522int	command(const char *, int);
523int	shell(Source *volatile, int volatile);
524void	unwind(int) __attribute__((__noreturn__));
525void	newenv(int);
526void	quitenv(struct shf *);
527void	cleanup_parents_env(void);
528void	cleanup_proc_env(void);
529/* misc.c */
530void	setctypes(const char *, int);
531void	initctypes(void);
532char *	u64ton(uint64_t, int);
533char *	str_save(const char *, Area *);
534char *	str_nsave(const char *, int, Area *);
535int	option(const char *);
536char *	getoptions(void);
537void	change_flag(enum sh_flag, int, int);
538int	parse_args(char **, int, int *);
539int	getn(const char *, int *);
540int	bi_getn(const char *, int *);
541int	gmatch(const char *, const char *, int);
542int	has_globbing(const char *, const char *);
543const unsigned char *pat_scan(const unsigned char *, const unsigned char *,
544    int);
545void	qsortp(void **, size_t, int (*)(const void *, const void *));
546int	xstrcmp(const void *, const void *);
547void	ksh_getopt_reset(Getopt *, int);
548int	ksh_getopt(char **, Getopt *, const char *);
549void	print_value_quoted(const char *);
550void	print_columns(struct shf *, int, char *(*)(void *, int, char *, int),
551    void *, int, int prefcol);
552int	strip_nuls(char *, int);
553int	blocking_read(int, char *, int);
554int	reset_nonblock(int);
555char	*ksh_get_wd(char *, int);
556/* path.c */
557int	make_path(const char *, const char *, char **, XString *, int *);
558void	simplify_path(char *);
559char	*get_phys_path(const char *);
560void	set_current_wd(char *);
561/* syn.c */
562void	initkeywords(void);
563struct op * compile(Source *);
564/* trap.c */
565void	inittraps(void);
566void	alarm_init(void);
567Trap *	gettrap(const char *, int);
568void	trapsig(int);
569void	intrcheck(void);
570int	fatal_trap_check(void);
571int	trap_pending(void);
572void	runtraps(int intr);
573void	runtrap(Trap *);
574void	cleartraps(void);
575void	restoresigs(void);
576void	settrap(Trap *, char *);
577int	block_pipe(void);
578void	restore_pipe(int);
579int	setsig(Trap *, sig_t, int);
580void	setexecsig(Trap *, int);
581/* var.c */
582void	newblock(void);
583void	popblock(void);
584void	initvar(void);
585struct tbl *	global(const char *);
586struct tbl *	local(const char *, bool);
587char *	str_val(struct tbl *);
588int64_t	intval(struct tbl *);
589int	setstr(struct tbl *, const char *, int);
590struct tbl *setint_v(struct tbl *, struct tbl *, bool);
591void	setint(struct tbl *, int64_t);
592int	getint(struct tbl *, int64_t *, bool);
593struct tbl *typeset(const char *, int, int, int, int);
594void	unset(struct tbl *, int);
595char  * skip_varname(const char *, int);
596char	*skip_wdvarname(const char *, int);
597int	is_wdvarname(const char *, int);
598int	is_wdvarassign(const char *);
599char **	makenv(void);
600void	change_random(void);
601int	array_ref_len(const char *);
602char *	arrayname(const char *);
603void    set_array(const char *, int, char **);
604/* vi.c: see edit.h */
605