xref: /original-bsd/bin/csh/csh.h (revision 61b6c03f)
1 /*
2  * Copyright (c) 1980 Regents of the University of California.
3  * All rights reserved.  The Berkeley Software License Agreement
4  * specifies the terms and conditions for redistribution.
5  *
6  *	@(#)csh.h	5.3 (Berkeley) 03/29/86
7  */
8 
9 #include <sys/time.h>
10 #include <sys/resource.h>
11 #include <sys/param.h>
12 #include <sys/stat.h>
13 #include <sys/signal.h>
14 #include <errno.h>
15 #include <setjmp.h>
16 #include "sh.local.h"
17 #include "sh.char.h"
18 
19 /*
20  * C shell
21  *
22  * Bill Joy, UC Berkeley
23  * October, 1978; May 1980
24  *
25  * Jim Kulp, IIASA, Laxenburg Austria
26  * April, 1980
27  */
28 
29 #define	isdir(d)	((d.st_mode & S_IFMT) == S_IFDIR)
30 
31 typedef	char	bool;
32 
33 #define	eq(a, b)	(strcmp(a, b) == 0)
34 
35 /*
36  * Global flags
37  */
38 bool	chkstop;		/* Warned of stopped jobs... allow exit */
39 bool	didfds;			/* Have setup i/o fd's for child */
40 bool	doneinp;		/* EOF indicator after reset from readc */
41 bool	exiterr;		/* Exit if error or non-zero exit status */
42 bool	child;			/* Child shell ... errors cause exit */
43 bool	haderr;			/* Reset was because of an error */
44 bool	intty;			/* Input is a tty */
45 bool	intact;			/* We are interactive... therefore prompt */
46 bool	justpr;			/* Just print because of :p hist mod */
47 bool	loginsh;		/* We are a loginsh -> .login/.logout */
48 bool	neednote;		/* Need to pnotify() */
49 bool	noexec;			/* Don't execute, just syntax check */
50 bool	pjobs;			/* want to print jobs if interrupted */
51 bool	setintr;		/* Set interrupts on/off -> Wait intr... */
52 bool	timflg;			/* Time the next waited for command */
53 bool	havhash;		/* path hashing is available */
54 #ifdef FILEC
55 bool	filec;			/* doing filename expansion */
56 #endif
57 
58 /*
59  * Global i/o info
60  */
61 char	*arginp;		/* Argument input for sh -c and internal `xx` */
62 int	onelflg;		/* 2 -> need line for -t, 1 -> exit on read */
63 char	*file;			/* Name of shell file for $0 */
64 
65 char	*err;			/* Error message from scanner/parser */
66 int	errno;			/* Error from C library routines */
67 char	*shtemp;		/* Temp name for << shell files in /tmp */
68 struct	timeval time0;		/* Time at which the shell started */
69 struct	rusage ru0;
70 
71 /*
72  * Miscellany
73  */
74 char	*doldol;		/* Character pid for $$ */
75 int	uid;			/* Invokers uid */
76 time_t	chktim;			/* Time mail last checked */
77 int	shpgrp;			/* Pgrp of shell */
78 int	tpgrp;			/* Terminal process group */
79 /* If tpgrp is -1, leave tty alone! */
80 int	opgrp;			/* Initial pgrp and tty pgrp */
81 int	oldisc;			/* Initial line discipline or -1 */
82 
83 /*
84  * These are declared here because they want to be
85  * initialized in sh.init.c (to allow them to be made readonly)
86  */
87 
88 struct	biltins {
89 	char	*bname;
90 	int	(*bfunct)();
91 	short	minargs, maxargs;
92 } bfunc[];
93 extern int nbfunc;
94 
95 struct srch {
96 	char	*s_name;
97 	short	s_value;
98 } srchn[];
99 extern int nsrchn;
100 
101 /*
102  * To be able to redirect i/o for builtins easily, the shell moves the i/o
103  * descriptors it uses away from 0,1,2.
104  * Ideally these should be in units which are closed across exec's
105  * (this saves work) but for version 6, this is not usually possible.
106  * The desired initial values for these descriptors are defined in
107  * sh.local.h.
108  */
109 short	SHIN;			/* Current shell input (script) */
110 short	SHOUT;			/* Shell output */
111 short	SHDIAG;			/* Diagnostic output... shell errs go here */
112 short	OLDSTD;			/* Old standard input (def for cmds) */
113 
114 /*
115  * Error control
116  *
117  * Errors in scanning and parsing set up an error message to be printed
118  * at the end and complete.  Other errors always cause a reset.
119  * Because of source commands and .cshrc we need nested error catches.
120  */
121 
122 jmp_buf	reslab;
123 
124 #define	setexit()	((void) setjmp(reslab))
125 #define	reset()		longjmp(reslab, 0)
126 	/* Should use structure assignment here */
127 #define	getexit(a)	copy((char *)(a), (char *)reslab, sizeof reslab)
128 #define	resexit(a)	copy((char *)reslab, ((char *)(a)), sizeof reslab)
129 
130 char	*gointr;		/* Label for an onintr transfer */
131 int	(*parintr)();		/* Parents interrupt catch */
132 int	(*parterm)();		/* Parents terminate catch */
133 
134 /*
135  * Lexical definitions.
136  *
137  * All lexical space is allocated dynamically.
138  * The eighth bit of characters is used to prevent recognition,
139  * and eventually stripped.
140  */
141 #define	QUOTE 	0200		/* Eighth char bit used internally for 'ing */
142 #define	TRIM	0177		/* Mask to strip quote bit */
143 
144 /*
145  * Each level of input has a buffered input structure.
146  * There are one or more blocks of buffered input for each level,
147  * exactly one if the input is seekable and tell is available.
148  * In other cases, the shell buffers enough blocks to keep all loops
149  * in the buffer.
150  */
151 struct	Bin {
152 	off_t	Bfseekp;		/* Seek pointer */
153 	off_t	Bfbobp;			/* Seekp of beginning of buffers */
154 	off_t	Bfeobp;			/* Seekp of end of buffers */
155 	short	Bfblocks;		/* Number of buffer blocks */
156 	char	**Bfbuf;		/* The array of buffer blocks */
157 } B;
158 
159 #define	fseekp	B.Bfseekp
160 #define	fbobp	B.Bfbobp
161 #define	feobp	B.Bfeobp
162 #define	fblocks	B.Bfblocks
163 #define	fbuf	B.Bfbuf
164 
165 #define btell()	fseekp
166 
167 #ifndef btell
168 off_t	btell();
169 #endif
170 
171 /*
172  * The shell finds commands in loops by reseeking the input
173  * For whiles, in particular, it reseeks to the beginning of the
174  * line the while was on; hence the while placement restrictions.
175  */
176 off_t	lineloc;
177 
178 #ifdef	TELL
179 bool	cantell;			/* Is current source tellable ? */
180 #endif
181 
182 /*
183  * Input lines are parsed into doubly linked circular
184  * lists of words of the following form.
185  */
186 struct	wordent {
187 	char	*word;
188 	struct	wordent *prev;
189 	struct	wordent *next;
190 };
191 
192 /*
193  * During word building, both in the initial lexical phase and
194  * when expanding $ variable substitutions, expansion by `!' and `$'
195  * must be inhibited when reading ahead in routines which are themselves
196  * processing `!' and `$' expansion or after characters such as `\' or in
197  * quotations.  The following flags are passed to the getC routines
198  * telling them which of these substitutions are appropriate for the
199  * next character to be returned.
200  */
201 #define	DODOL	1
202 #define	DOEXCL	2
203 #define	DOALL	DODOL|DOEXCL
204 
205 /*
206  * Labuf implements a general buffer for lookahead during lexical operations.
207  * Text which is to be placed in the input stream can be stuck here.
208  * We stick parsed ahead $ constructs during initial input,
209  * process id's from `$$', and modified variable values (from qualifiers
210  * during expansion in sh.dol.c) here.
211  */
212 char	labuf[BUFSIZ];
213 
214 char	*lap;
215 
216 /*
217  * Parser structure
218  *
219  * Each command is parsed to a tree of command structures and
220  * flags are set bottom up during this process, to be propagated down
221  * as needed during the semantics/exeuction pass (sh.sem.c).
222  */
223 struct	command {
224 	short	t_dtyp;				/* Type of node */
225 	short	t_dflg;				/* Flags, e.g. FAND|... */
226 	union {
227 		char	*T_dlef;		/* Input redirect word */
228 		struct	command *T_dcar;	/* Left part of list/pipe */
229 	} L;
230 	union {
231 		char	*T_drit;		/* Output redirect word */
232 		struct	command *T_dcdr;	/* Right part of list/pipe */
233 	} R;
234 #define	t_dlef	L.T_dlef
235 #define	t_dcar	L.T_dcar
236 #define	t_drit	R.T_drit
237 #define	t_dcdr	R.T_dcdr
238 	char	**t_dcom;			/* Command/argument vector */
239 	struct	command *t_dspr;		/* Pointer to ()'d subtree */
240 	short	t_nice;
241 };
242 
243 #define	TCOM	1		/* t_dcom <t_dlef >t_drit	*/
244 #define	TPAR	2		/* ( t_dspr ) <t_dlef >t_drit	*/
245 #define	TFIL	3		/* t_dlef | t_drit		*/
246 #define	TLST	4		/* t_dlef ; t_drit		*/
247 #define	TOR	5		/* t_dlef || t_drit		*/
248 #define	TAND	6		/* t_dlef && t_drit		*/
249 
250 #define	FSAVE	(FNICE|FTIME|FNOHUP)	/* save these when re-doing */
251 
252 #define	FAND	(1<<0)		/* executes in background	*/
253 #define	FCAT	(1<<1)		/* output is redirected >>	*/
254 #define	FPIN	(1<<2)		/* input is a pipe		*/
255 #define	FPOU	(1<<3)		/* output is a pipe		*/
256 #define	FPAR	(1<<4)		/* don't fork, last ()ized cmd	*/
257 #define	FINT	(1<<5)		/* should be immune from intr's */
258 /* spare */
259 #define	FDIAG	(1<<7)		/* redirect unit 2 with unit 1	*/
260 #define	FANY	(1<<8)		/* output was !			*/
261 #define	FHERE	(1<<9)		/* input redirection is <<	*/
262 #define	FREDO	(1<<10)		/* reexec aft if, repeat,...	*/
263 #define	FNICE	(1<<11)		/* t_nice is meaningful */
264 #define	FNOHUP	(1<<12)		/* nohup this command */
265 #define	FTIME	(1<<13)		/* time this command */
266 
267 /*
268  * The keywords for the parser
269  */
270 #define	ZBREAK		0
271 #define	ZBRKSW		1
272 #define	ZCASE		2
273 #define	ZDEFAULT 	3
274 #define	ZELSE		4
275 #define	ZEND		5
276 #define	ZENDIF		6
277 #define	ZENDSW		7
278 #define	ZEXIT		8
279 #define	ZFOREACH	9
280 #define	ZGOTO		10
281 #define	ZIF		11
282 #define	ZLABEL		12
283 #define	ZLET		13
284 #define	ZSET		14
285 #define	ZSWITCH		15
286 #define	ZTEST		16
287 #define	ZTHEN		17
288 #define	ZWHILE		18
289 
290 /*
291  * Structure defining the existing while/foreach loops at this
292  * source level.  Loops are implemented by seeking back in the
293  * input.  For foreach (fe), the word list is attached here.
294  */
295 struct	whyle {
296 	off_t	w_start;		/* Point to restart loop */
297 	off_t	w_end;			/* End of loop (0 if unknown) */
298 	char	**w_fe, **w_fe0;	/* Current/initial wordlist for fe */
299 	char	*w_fename;		/* Name for fe */
300 	struct	whyle *w_next;		/* Next (more outer) loop */
301 } *whyles;
302 
303 /*
304  * Variable structure
305  *
306  * Aliases and variables are stored in AVL balanced binary trees.
307  */
308 struct	varent {
309 	char	**vec;		/* Array of words which is the value */
310 	char	*v_name;	/* Name of variable/alias */
311 	struct	varent *v_link[3];	/* The links, see below */
312 	int	v_bal;		/* Balance factor */
313 } shvhed, aliases;
314 #define v_left		v_link[0]
315 #define v_right		v_link[1]
316 #define v_parent	v_link[2]
317 
318 struct varent *adrof1();
319 #define adrof(v)	adrof1(v, &shvhed)
320 #define value(v)	value1(v, &shvhed)
321 
322 /*
323  * The following are for interfacing redo substitution in
324  * aliases to the lexical routines.
325  */
326 struct	wordent *alhistp;		/* Argument list (first) */
327 struct	wordent *alhistt;		/* Node after last in arg list */
328 char	**alvec;			/* The (remnants of) alias vector */
329 
330 /*
331  * Filename/command name expansion variables
332  */
333 short	gflag;				/* After tglob -> is globbing needed? */
334 
335 /*
336  * A reasonable limit on number of arguments would seem to be
337  * the maximum number of characters in an arg list / 6.
338  */
339 #define	GAVSIZ	NCARGS / 6
340 
341 /*
342  * Variables for filename expansion
343  */
344 char	**gargv;			/* Pointer to the (stack) arglist */
345 short	gargc;				/* Number args in gargv */
346 short	gnleft;
347 
348 /*
349  * Variables for command expansion.
350  */
351 char	**pargv;			/* Pointer to the argv list space */
352 char	*pargs;				/* Pointer to start current word */
353 short	pargc;				/* Count of arguments in pargv */
354 short	pnleft;				/* Number of chars left in pargs */
355 char	*pargcp;			/* Current index into pargs */
356 
357 /*
358  * History list
359  *
360  * Each history list entry contains an embedded wordlist
361  * from the scanner, a number for the event, and a reference count
362  * to aid in discarding old entries.
363  *
364  * Essentially "invisible" entries are put on the history list
365  * when history substitution includes modifiers, and thrown away
366  * at the next discarding since their event numbers are very negative.
367  */
368 struct	Hist {
369 	struct	wordent Hlex;
370 	int	Hnum;
371 	int	Href;
372 	struct	Hist *Hnext;
373 } Histlist;
374 
375 struct	wordent	paraml;			/* Current lexical word list */
376 int	eventno;			/* Next events number */
377 int	lastev;				/* Last event reference (default) */
378 
379 char	HIST;				/* history invocation character */
380 char	HISTSUB;			/* auto-substitute character */
381 
382 /*
383  * In lines for frequently called functions
384  */
385 #define XFREE(cp) { \
386 	extern char end[]; \
387 	char stack; \
388 	if ((cp) >= end && (cp) < &stack) \
389 		free(cp); \
390 }
391 char	*alloctmp;
392 #define xalloc(i) ((alloctmp = malloc(i)) ? alloctmp : (char *)nomem(i))
393 
394 char	*Dfix1();
395 char	**blkcat();
396 char	**blkcpy();
397 char	**blkend();
398 char	**blkspl();
399 char	*calloc();
400 char	*malloc();
401 char	*cname();
402 char	**copyblk();
403 char	**dobackp();
404 char	*domod();
405 struct	wordent *dosub();
406 char	*exp3();
407 char	*exp3a();
408 char	*exp4();
409 char	*exp5();
410 char	*exp6();
411 struct	Hist *enthist();
412 struct	Hist *findev();
413 struct	wordent *freenod();
414 char	*getenv();
415 char	*getinx();
416 struct	varent *getvx();
417 struct	passwd *getpwnam();
418 struct	wordent *gethent();
419 struct	wordent *getsub();
420 char	*getwd();
421 char	**glob();
422 char	*globone();
423 char	*index();
424 struct	biltins *isbfunc();
425 off_t	lseek();
426 char	*operate();
427 int	phup();
428 int	pintr();
429 int	pchild();
430 char	*putn();
431 char	*rindex();
432 char	**saveblk();
433 char	*savestr();
434 char	*strcat();
435 char	*strcpy();
436 char	*strend();
437 char	*strings();
438 char	*strip();
439 char	*strspl();
440 char	*subword();
441 struct	command *syntax();
442 struct	command *syn0();
443 struct	command *syn1();
444 struct	command *syn1a();
445 struct	command *syn1b();
446 struct	command *syn2();
447 struct	command *syn3();
448 char	*value1();
449 char	*xhome();
450 char	*xname();
451 char	*xset();
452 
453 #define	NOSTR	((char *) 0)
454 
455 /*
456  * setname is a macro to save space (see sh.err.c)
457  */
458 char	*bname;
459 #define	setname(a)	(bname = (a))
460 
461 #ifdef VFORK
462 char	*Vsav;
463 char	**Vav;
464 char	*Vdp;
465 #endif
466 
467 char	**evalvec;
468 char	*evalp;
469 
470 struct	mesg {
471 	char	*iname;		/* name from /usr/include */
472 	char	*pname;		/* print name */
473 } mesg[];
474