xref: /netbsd/bin/ksh/sh.h (revision 113a3e84)
1 /*	$NetBSD: sh.h,v 1.35 2017/06/30 04:44:46 kamil Exp $	*/
2 
3 /*
4  * Public Domain Bourne/Korn shell
5  */
6 
7 /* $Id: sh.h,v 1.35 2017/06/30 04:44:46 kamil Exp $ */
8 
9 #include "config.h"	/* system and option configuration info */
10 
11 #define	ARGS(args)	args	/* prototype declaration */
12 
13 /* Start of common headers */
14 
15 #include <stdio.h>
16 #include <sys/types.h>
17 #include <setjmp.h>
18 #include <stddef.h>
19 #include <stdlib.h>
20 #include <unistd.h>
21 #include <string.h>
22 #include <stdarg.h>
23 #include <errno.h>
24 #include <fcntl.h>
25 #include <stdint.h>
26 
27 #ifndef O_ACCMODE
28 # define O_ACCMODE	(O_RDONLY|O_WRONLY|O_RDWR)
29 #endif /* !O_ACCMODE */
30 
31 #ifndef F_OK 	/* access() arguments */
32 # define F_OK 0
33 # define X_OK 1
34 # define W_OK 2
35 # define R_OK 4
36 #endif /* !F_OK */
37 
38 #ifndef SEEK_SET
39 # ifdef L_SET
40 #  define SEEK_SET L_SET
41 #  define SEEK_CUR L_INCR
42 #  define SEEK_END L_XTND
43 # else /* L_SET */
44 #  define SEEK_SET 0
45 #  define SEEK_CUR 1
46 #  define SEEK_END 2
47 # endif /* L_SET */
48 #endif /* !SEEK_SET */
49 
50 #include <limits.h>
51 
52 #include <signal.h>
53 #ifdef	NSIG
54 # define SIGNALS	NSIG
55 #else
56 # ifdef	_MINIX
57 #  define SIGNALS	(_NSIG+1) /* _NSIG is # of signals used, excluding 0. */
58 # else
59 #  ifdef _SIGMAX	/* QNX */
60 #   define SIGNALS	_SIGMAX
61 #  else /* _SIGMAX */
62 #   define SIGNALS	32
63 #  endif /* _SIGMAX */
64 # endif	/* _MINIX */
65 #endif	/* NSIG */
66 #ifndef SIGCHLD
67 # define SIGCHLD SIGCLD
68 #endif
69 /* struct sigaction.sa_flags is set to KSH_SA_FLAGS.  Used to ensure
70  * system calls are interrupted
71  */
72 #ifdef SA_INTERRUPT
73 # define KSH_SA_FLAGS	SA_INTERRUPT
74 #else /* SA_INTERRUPT */
75 # define KSH_SA_FLAGS	0
76 #endif /* SA_INTERRUPT */
77 
78 typedef	RETSIGTYPE (*handler_t) ARGS((int));	/* signal handler */
79 
80 #ifdef HAVE_PATHS_H
81 # include <paths.h>
82 #endif /* HAVE_PATHS_H */
83 #ifdef _PATH_DEFPATH
84 # define DEFAULT__PATH _PATH_DEFPATH
85 #else /* _PATH_DEFPATH */
86 # define DEFAULT__PATH DEFAULT_PATH
87 #endif /* _PATH_DEFPATH */
88 
89 #ifndef HAVE_KILLPG
90 # define killpg(p, s)	kill(-(p), (s))
91 #endif /* !HAVE_KILLPG */
92 
93 /* this is a hang-over from older versions of the os2 port */
94 #define ksh_dupbase(fd, base) fcntl(fd, F_DUPFD, base)
95 
96 #ifdef HAVE_SIGSETJMP
97 # define ksh_sigsetjmp(env,sm)	sigsetjmp((env), (sm))
98 # define ksh_siglongjmp(env,v)	siglongjmp((env), (v))
99 # define ksh_jmp_buf		sigjmp_buf
100 #else /* HAVE_SIGSETJMP */
101 # ifdef HAVE__SETJMP
102 #  define ksh_sigsetjmp(env,sm)	_setjmp(env)
103 #  define ksh_siglongjmp(env,v)	_longjmp((env), (v))
104 # else /* HAVE__SETJMP */
105 #  define ksh_sigsetjmp(env,sm)	setjmp(env)
106 #  define ksh_siglongjmp(env,v)	longjmp((env), (v))
107 # endif /* HAVE__SETJMP */
108 # define ksh_jmp_buf		jmp_buf
109 #endif /* HAVE_SIGSETJMP */
110 
111 /* end of common headers */
112 
113 /* Stop gcc and lint from complaining about possibly uninitialized variables */
114 #if defined(__GNUC__) || defined(lint)
115 # define UNINITIALIZED(var)	var = 0
116 #else
117 # define UNINITIALIZED(var)	var
118 #endif /* GNUC || lint */
119 
120 /* some useful #defines */
121 #ifdef EXTERN
122 # define I__(i) = i
123 #else
124 # define I__(i)
125 # define EXTERN extern
126 # define EXTERN_DEFINED
127 #endif
128 
129 #ifndef EXECSHELL
130 /* shell to exec scripts (see also $SHELL initialization in main.c) */
131 #  define EXECSHELL	"/bin/sh"
132 #  define EXECSHELL_STR	"EXECSHELL"
133 #endif
134 
135 /* ISABSPATH() means path is fully and completely specified,
136  * ISROOTEDPATH() means a .. as the first component is a no-op,
137  * ISRELPATH() means $PWD can be tacked on to get an absolute path.
138  *
139  * OS		Path		ISABSPATH	ISROOTEDPATH	ISRELPATH
140  * unix		/foo		yes		yes		no
141  * unix		foo		no		no		yes
142  * unix		../foo		no		no		yes
143  */
144 # define PATHSEP        ':'
145 # define DIRSEP         '/'
146 # define DIRSEPSTR      "/"
147 # define ISDIRSEP(c)    ((c) == '/')
148 # define ISABSPATH(s)	ISDIRSEP((s)[0])
149 # define ISRELPATH(s)	(!ISABSPATH(s))
150 # define ISROOTEDPATH(s) ISABSPATH(s)
151 # define FILECHCONV(c)	c
152 # define FILECMP(s1, s2) strcmp(s1, s2)
153 # define FILENCMP(s1, s2, n) strncmp(s1, s2, n)
154 # define ksh_strchr_dirsep(p)   strchr(p, DIRSEP)
155 # define ksh_strrchr_dirsep(p)  strrchr(p, DIRSEP)
156 
157 #define	NELEM(a) (sizeof(a) / sizeof((a)[0]))
158 #define	sizeofN(type, n) (sizeof(type) * (n))
159 #define	BIT(i)	(1<<(i))	/* define bit in flag */
160 
161 /* Table flag type - needs > 16 and < 32 bits */
162 typedef int_least32_t Tflag;
163 
164 #define	NUFILE	32		/* Number of user-accessible files */
165 #define	FDBASE	10		/* First file usable by Shell */
166 
167 /* you're not going to run setuid shell scripts, are you? */
168 #define	eaccess(path, mode)	access(path, mode)
169 
170 /* Make MAGIC a char that might be printed to make bugs more obvious, but
171  * not a char that is used often.  Also, can't use the high bit as it causes
172  * portability problems (calling strchr(x, 0x80|'x') is error prone).
173  */
174 #define	MAGIC		(7)	/* prefix for *?[!{,} during expand */
175 #define ISMAGIC(c)	((unsigned char)(c) == MAGIC)
176 #define	NOT		'!'	/* might use ^ (ie, [!...] vs [^..]) */
177 
178 #define	LINE	1024		/* input line size */
179 #define	PATH	1024		/* pathname size (todo: PATH_MAX/pathconf()) */
180 #define ARRAYMAX 1023		/* max array index */
181 
182 EXTERN	const char *kshname;	/* $0 */
183 EXTERN	pid_t	kshpid;		/* $$, shell pid */
184 EXTERN	pid_t	procpid;	/* pid of executing process */
185 EXTERN	uid_t	ksheuid;	/* effective uid of shell */
186 EXTERN	int	exstat;		/* exit status */
187 EXTERN	int	subst_exstat;	/* exit status of last $(..)/`..` */
188 EXTERN	const char *safe_prompt; /* safe prompt if PS1 substitution fails */
189 
190 /*
191  * Area-based allocation built on malloc/free
192  */
193 typedef struct Area {
194 	struct link *freelist;	/* free list */
195 } Area;
196 
197 EXTERN	Area	aperm;		/* permanent object space */
198 #define	APERM	&aperm
199 #define	ATEMP	&e->area
200 
201 #ifdef KSH_DEBUG
202 # define kshdebug_init()	kshdebug_init_()
203 # define kshdebug_printf(a)	kshdebug_printf_ a
204 # define kshdebug_dump(a)	kshdebug_dump_ a
205 #else /* KSH_DEBUG */
206 # define kshdebug_init()
207 # define kshdebug_printf(a)
208 # define kshdebug_dump(a)
209 #endif /* KSH_DEBUG */
210 
211 /*
212  * parsing & execution environment
213  */
214 EXTERN	struct env {
215 	short	type;			/* environment type - see below */
216 	short	flags;			/* EF_* */
217 	Area	area;			/* temporary allocation area */
218 	struct	block *loc;		/* local variables and functions */
219 	short  *savefd;			/* original redirected fd's */
220 	struct	env *oenv;		/* link to previous environment */
221 	ksh_jmp_buf jbuf;		/* long jump back to env creator */
222 	struct temp *temps;		/* temp files */
223 } *e;
224 
225 /* struct env.type values */
226 #define	E_NONE	0		/* dummy environment */
227 #define	E_PARSE	1		/* parsing command # */
228 #define	E_FUNC	2		/* executing function # */
229 #define	E_INCL	3		/* including a file via . # */
230 #define	E_EXEC	4		/* executing command tree */
231 #define	E_LOOP	5		/* executing for/while # */
232 #define	E_ERRH	6		/* general error handler # */
233 /* # indicates env has valid jbuf (see unwind()) */
234 
235 /* struct env.flag values */
236 #define EF_FUNC_PARSE	BIT(0)	/* function being parsed */
237 #define EF_BRKCONT_PASS	BIT(1)	/* set if E_LOOP must pass break/continue on */
238 #define EF_FAKE_SIGDIE	BIT(2)	/* hack to get info from unwind to quitenv */
239 
240 /* Do breaks/continues stop at env type e? */
241 #define STOP_BRKCONT(t)	((t) == E_NONE || (t) == E_PARSE \
242 			 || (t) == E_FUNC || (t) == E_INCL)
243 /* Do returns stop at env type e? */
244 #define STOP_RETURN(t)	((t) == E_FUNC || (t) == E_INCL)
245 
246 /* values for ksh_siglongjmp(e->jbuf, 0) */
247 #define LRETURN	1		/* return statement */
248 #define	LEXIT	2		/* exit statement */
249 #define LERROR	3		/* errorf() called */
250 #define LLEAVE	4		/* untrappable exit/error */
251 #define LINTR	5		/* ^C noticed */
252 #define	LBREAK	6		/* break statement */
253 #define	LCONTIN	7		/* continue statement */
254 #define LSHELL	8		/* return to interactive shell() */
255 #define LAEXPR	9		/* error in arithmetic expression */
256 
257 /* option processing */
258 #define OF_CMDLINE	0x01	/* command line */
259 #define OF_SET		0x02	/* set builtin */
260 #define OF_SPECIAL	0x04	/* a special variable changing */
261 #define OF_INTERNAL	0x08	/* set internally by shell */
262 #define OF_ANY		(OF_CMDLINE | OF_SET | OF_SPECIAL | OF_INTERNAL)
263 
264 struct option {
265     const char	*name;	/* long name of option */
266     char	c;	/* character flag (if any) */
267     short	flags;	/* OF_* */
268 };
269 extern const struct option goptions[];
270 
271 /*
272  * flags (the order of these enums MUST match the order in misc.c(options[]))
273  */
274 enum sh_flag {
275 	FEXPORT = 0,	/* -a: export all */
276 #ifdef BRACE_EXPAND
277 	FBRACEEXPAND,	/* enable {} globbing */
278 #endif
279 	FBGNICE,	/* bgnice */
280 	FCOMMAND,	/* -c: (invocation) execute specified command */
281 #ifdef EMACS
282 	FEMACS,		/* emacs command editing */
283 	FEMACSUSEMETA,	/* use 8th bit as meta */
284 #endif
285 	FERREXIT,	/* -e: quit on error */
286 #ifdef EMACS
287 	FGMACS,		/* gmacs command editing */
288 #endif
289 	FIGNOREEOF,	/* eof does not exit */
290 	FTALKING,	/* -i: interactive */
291 	FKEYWORD,	/* -k: name=value anywhere */
292 	FLOGIN,		/* -l: a login shell */
293 	FMARKDIRS,	/* mark dirs with / in file name completion */
294 	FMONITOR,	/* -m: job control monitoring */
295 	FNOCLOBBER,	/* -C: don't overwrite existing files */
296 	FNOEXEC,	/* -n: don't execute any commands */
297 	FNOGLOB,	/* -f: don't do file globbing */
298 	FNOHUP,		/* -H: don't kill running jobs when login shell exits */
299 	FNOLOG,		/* don't save functions in history (ignored) */
300 #ifdef	JOBS
301 	FNOTIFY,	/* -b: asynchronous job completion notification */
302 #endif
303 	FNOUNSET,	/* -u: using an unset var is an error */
304 	FPHYSICAL,	/* -o physical: don't do logical cd's/pwd's */
305 	FPOSIX,		/* -o posix: be posixly correct */
306 	FPRIVILEGED,	/* -p: use suid_profile */
307 	FRESTRICTED,	/* -r: restricted shell */
308 	FSTDIN,		/* -s: (invocation) parse stdin */
309 	FTRACKALL,	/* -h: create tracked aliases for all commands */
310 	FVERBOSE,	/* -v: echo input */
311 #ifdef VI
312 	FVI,		/* vi command editing */
313 	FVIRAW,		/* always read in raw mode (ignored) */
314 	FVISHOW8,	/* display chars with 8th bit set as is (versus M-) */
315 	FVITABCOMPLETE,	/* enable tab as file name completion char */
316 	FVIESCCOMPLETE,	/* enable ESC as file name completion in command mode */
317 #endif
318 	FXTRACE,	/* -x: execution trace */
319 	FTALKING_I,	/* (internal): initial shell was interactive */
320 	FNFLAGS /* (place holder: how many flags are there) */
321 };
322 
323 #define Flag(f)	(shell_flags[(int) (f)])
324 
325 EXTERN	char shell_flags [FNFLAGS];
326 
327 EXTERN	char	null [] I__("");	/* null value for variable */
328 EXTERN	char	space [] I__(" ");
329 EXTERN	char	newline [] I__("\n");
330 EXTERN	char	slash [] I__("/");
331 
332 enum temp_type {
333     TT_HEREDOC_EXP,	/* expanded heredoc */
334     TT_HIST_EDIT	/* temp file used for history editing (fc -e) */
335 };
336 typedef enum temp_type Temp_type;
337 /* temp/heredoc files.  The file is removed when the struct is freed. */
338 struct temp {
339 	struct temp	*next;
340 	struct shf	*shf;
341 	int		pid;		/* pid of process parsed here-doc */
342 	Temp_type	type;
343 	char		*name;
344 };
345 
346 /*
347  * stdio and our IO routines
348  */
349 
350 #define shl_spare	(&shf_iob[0])	/* for c_read()/c_print() */
351 #define shl_stdout	(&shf_iob[1])
352 #define shl_out		(&shf_iob[2])
353 EXTERN int shl_stdout_ok;
354 
355 /*
356  * trap handlers
357  */
358 typedef struct trap {
359 	int	signal;		/* signal number */
360 	const char *name;	/* short name */
361 	const char *mess;	/* descriptive name */
362 	char   *trap;		/* trap command */
363 	int	volatile set;	/* trap pending */
364 	int	flags;		/* TF_* */
365 	handler_t cursig;	/* current handler (valid if TF_ORIG_* set) */
366 	handler_t shtrap;	/* shell signal handler */
367 } Trap;
368 
369 /* values for Trap.flags */
370 #define TF_SHELL_USES	BIT(0)	/* shell uses signal, user can't change */
371 #define TF_USER_SET	BIT(1)	/* user has (tried to) set trap */
372 #define TF_ORIG_IGN	BIT(2)	/* original action was SIG_IGN */
373 #define TF_ORIG_DFL	BIT(3)	/* original action was SIG_DFL */
374 #define TF_EXEC_IGN	BIT(4)	/* restore SIG_IGN just before exec */
375 #define TF_EXEC_DFL	BIT(5)	/* restore SIG_DFL just before exec */
376 #define TF_DFL_INTR	BIT(6)	/* when received, default action is LINTR */
377 #define TF_TTY_INTR	BIT(7)	/* tty generated signal (see j_waitj) */
378 #define TF_CHANGED	BIT(8)	/* used by runtrap() to detect trap changes */
379 #define TF_FATAL	BIT(9)	/* causes termination if not trapped */
380 
381 /* values for setsig()/setexecsig() flags argument */
382 #define SS_RESTORE_MASK	0x3	/* how to restore a signal before an exec() */
383 #define SS_RESTORE_CURR	0	/* leave current handler in place */
384 #define SS_RESTORE_ORIG	1	/* restore original handler */
385 #define SS_RESTORE_DFL	2	/* restore to SIG_DFL */
386 #define SS_RESTORE_IGN	3	/* restore to SIG_IGN */
387 #define SS_FORCE	BIT(3)	/* set signal even if original signal ignored */
388 #define SS_USER		BIT(4)	/* user is doing the set (ie, trap command) */
389 #define SS_SHTRAP	BIT(5)	/* trap for internal use (CHLD,ALRM,WINCH) */
390 
391 #define SIGEXIT_	0	/* for trap EXIT */
392 #define SIGERR_		SIGNALS	/* for trap ERR */
393 
394 EXTERN	int volatile trap;	/* traps pending? */
395 EXTERN	int volatile intrsig;	/* pending trap interrupts executing command */
396 EXTERN	int volatile fatal_trap;/* received a fatal signal */
397 extern	Trap	sigtraps[SIGNALS+1];
398 
399 #ifdef KSH
400 /*
401  * TMOUT support
402  */
403 /* values for ksh_tmout_state */
404 enum tmout_enum {
405 		TMOUT_EXECUTING	= 0,	/* executing commands */
406 		TMOUT_READING,		/* waiting for input */
407 		TMOUT_LEAVING		/* have timed out */
408 	};
409 EXTERN unsigned int ksh_tmout;
410 EXTERN enum tmout_enum ksh_tmout_state I__(TMOUT_EXECUTING);
411 #endif /* KSH */
412 
413 /* For "You have stopped jobs" message */
414 EXTERN int really_exit;
415 
416 /*
417  * fast character classes
418  */
419 #define	C_ALPHA	 BIT(0)		/* a-z_A-Z */
420 #define	C_DIGIT	 BIT(1)		/* 0-9 */
421 #define	C_LEX1	 BIT(2)		/* \0 \t\n|&;<>() */
422 #define	C_VAR1	 BIT(3)		/* *@#!$-? */
423 #define	C_IFSWS	 BIT(4)		/* \t \n (IFS white space) */
424 #define	C_SUBOP1 BIT(5)		/* "=-+?" */
425 #define	C_SUBOP2 BIT(6)		/* "#%" */
426 #define	C_IFS	 BIT(7)		/* $IFS */
427 #define	C_QUOTE	 BIT(8)		/*  \n\t"#$&'()*;<>?[\`| (needing quoting) */
428 
429 extern	short ctypes [];
430 
431 #define	ctype(c, t)	!!(ctypes[(unsigned char)(c)]&(t))
432 #define	letter(c)	ctype(c, C_ALPHA)
433 #define	digit(c)	ctype(c, C_DIGIT)
434 #define	letnum(c)	ctype(c, C_ALPHA|C_DIGIT)
435 
436 EXTERN int ifs0 I__(' ');	/* for "$*" */
437 
438 /* Argument parsing for built-in commands and getopts command */
439 
440 /* Values for Getopt.flags */
441 #define GF_ERROR	BIT(0)	/* call errorf() if there is an error */
442 #define GF_PLUSOPT	BIT(1)	/* allow +c as an option */
443 #define GF_NONAME	BIT(2)	/* don't print argv[0] in errors */
444 
445 /* Values for Getopt.info */
446 #define GI_MINUS	BIT(0)	/* an option started with -... */
447 #define GI_PLUS		BIT(1)	/* an option started with +... */
448 #define GI_MINUSMINUS	BIT(2)	/* arguments were ended with -- */
449 
450 typedef struct {
451 	int		optind;
452 	int		uoptind;/* what user sees in $OPTIND */
453 	char		*optarg;
454 	int		flags;	/* see GF_* */
455 	int		info;	/* see GI_* */
456 	unsigned int	p;	/* 0 or index into argv[optind - 1] */
457 	char		buf[2];	/* for bad option OPTARG value */
458 } Getopt;
459 
460 EXTERN Getopt builtin_opt;	/* for shell builtin commands */
461 EXTERN Getopt user_opt;		/* parsing state for getopts builtin command */
462 
463 #ifdef KSH
464 /* This for co-processes */
465 
466 typedef int_least32_t Coproc_id; /* something that won't (realisticly) wrap */
467 struct coproc {
468 	int	read;		/* pipe from co-process's stdout */
469 	int	readw;		/* other side of read (saved temporarily) */
470 	int	write;		/* pipe to co-process's stdin */
471 	Coproc_id id;		/* id of current output pipe */
472 	int	njobs;		/* number of live jobs using output pipe */
473 	void    *job;           /* 0 or job of co-process using input pipe */
474 };
475 EXTERN struct coproc coproc;
476 #endif /* KSH */
477 
478 /* Used in jobs.c and by coprocess stuff in exec.c */
479 EXTERN sigset_t		sm_default, sm_sigchld;
480 
481 extern char ksh_version[];
482 
483 /* name of called builtin function (used by error functions) */
484 EXTERN char	*builtin_argv0;
485 EXTERN Tflag	builtin_flag;	/* flags of called builtin (SPEC_BI, etc.) */
486 
487 /* current working directory, and size of memory allocated for same */
488 EXTERN char	*current_wd;
489 EXTERN int	current_wd_size;
490 
491 #ifdef EDIT
492 /* Minimum required space to work with on a line - if the prompt leaves less
493  * space than this on a line, the prompt is truncated.
494  */
495 # define MIN_EDIT_SPACE	7
496 /* Minimum allowed value for x_cols: 2 for prompt, 3 for " < " at end of line
497  */
498 # define MIN_COLS	(2 + MIN_EDIT_SPACE + 3)
499 EXTERN	int	x_cols I__(80);	/* tty columns */
500 #else
501 # define x_cols 80		/* for pr_menu(exec.c) */
502 #endif
503 
504 /* These to avoid bracket matching problems */
505 #define OPAREN	'('
506 #define CPAREN	')'
507 #define OBRACK	'['
508 #define CBRACK	']'
509 #define OBRACE	'{'
510 #define CBRACE	'}'
511 
512 /* Determine the location of the system (common) profile */
513 #ifndef KSH_SYSTEM_PROFILE
514 # define KSH_SYSTEM_PROFILE "/etc/profile"
515 #endif /* KSH_SYSTEM_PROFILE */
516 
517 /* Used by v_evaluate() and setstr() to control action when error occurs */
518 #define KSH_UNWIND_ERROR	0	/* unwind the stack (longjmp) */
519 #define KSH_RETURN_ERROR	1	/* return 1/0 for success/failure */
520 
521 #include "shf.h"
522 #include "table.h"
523 #include "tree.h"
524 #include "expand.h"
525 #include "lex.h"
526 #include "proto.h"
527 
528 /* be sure not to interfere with anyone else's idea about EXTERN */
529 #ifdef EXTERN_DEFINED
530 # undef EXTERN_DEFINED
531 # undef EXTERN
532 #endif
533 #undef I__
534