xref: /original-bsd/usr.bin/ex/ex.c (revision d919d844)
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 
7 #ifndef lint
8 char *copyright =
9 "@(#) Copyright (c) 1980 Regents of the University of California.\n\
10  All rights reserved.\n";
11 #endif not lint
12 
13 #ifndef lint
14 static char *sccsid = "@(#)ex.c	7.6.1.1 (Berkeley) 08/08/88";
15 #endif not lint
16 
17 #include "ex.h"
18 #include "ex_argv.h"
19 #include "ex_temp.h"
20 #include "ex_tty.h"
21 
22 #ifdef TRACE
23 #ifdef	vms
24 char	tttrace[]	= { 't','r','a','c','e','.','l','i','s' };
25 #else
26 char	tttrace[]	= { '/','d','e','v','/','t','t','y','x','x',0 };
27 #endif
28 #endif
29 
30 /*
31  * The code for ex is divided as follows:
32  *
33  * ex.c			Entry point and routines handling interrupt, hangup
34  *			signals; initialization code.
35  *
36  * ex_addr.c		Address parsing routines for command mode decoding.
37  *			Routines to set and check address ranges on commands.
38  *
39  * ex_cmds.c		Command mode command decoding.
40  *
41  * ex_cmds2.c		Subroutines for command decoding and processing of
42  *			file names in the argument list.  Routines to print
43  *			messages and reset state when errors occur.
44  *
45  * ex_cmdsub.c		Subroutines which implement command mode functions
46  *			such as append, delete, join.
47  *
48  * ex_data.c		Initialization of options.
49  *
50  * ex_get.c		Command mode input routines.
51  *
52  * ex_io.c		General input/output processing: file i/o, unix
53  *			escapes, filtering, source commands, preserving
54  *			and recovering.
55  *
56  * ex_put.c		Terminal driving and optimizing routines for low-level
57  *			output (cursor-positioning); output line formatting
58  *			routines.
59  *
60  * ex_re.c		Global commands, substitute, regular expression
61  *			compilation and execution.
62  *
63  * ex_set.c		The set command.
64  *
65  * ex_subr.c		Loads of miscellaneous subroutines.
66  *
67  * ex_temp.c		Editor buffer routines for main buffer and also
68  *			for named buffers (Q registers if you will.)
69  *
70  * ex_tty.c		Terminal dependent initializations from termcap
71  *			data base, grabbing of tty modes (at beginning
72  *			and after escapes).
73  *
74  * ex_unix.c		Routines for the ! command and its variations.
75  *
76  * ex_v*.c		Visual/open mode routines... see ex_v.c for a
77  *			guide to the overall organization.
78  */
79 
80 /*
81  * Main procedure.  Process arguments and then
82  * transfer control to the main command processing loop
83  * in the routine commands.  We are entered as either "ex", "edit", "vi"
84  * or "view" and the distinction is made here.  Actually, we are "vi" if
85  * there is a 'v' in our name, "view" is there is a 'w', and "edit" if
86  * there is a 'd' in our name.  For edit we just diddle options;
87  * for vi we actually force an early visual command.
88  */
89 main(ac, av)
90 	register int ac;
91 	register char *av[];
92 {
93 #ifdef EXSTRINGS
94 	char *erpath = EXSTRINGS;
95 #endif
96 	register char *cp;
97 	register int c;
98 	bool recov = 0;
99 	bool ivis;
100 	bool itag = 0;
101 	bool fast = 0;
102 	extern int onemt();
103 #ifdef UNIX_SBRK
104 	extern char *sbrk();
105 #else
106 	extern char *malloc();
107 #endif
108 #ifdef TRACE
109 	register char *tracef;
110 #endif
111 #ifdef	vms
112 	char termtype[20];
113 #endif
114 
115 	/*
116 	 * Immediately grab the tty modes so that we wont
117 	 * get messed up if an interrupt comes in quickly.
118 	 */
119 	ex_gTTY(1);
120 #ifndef USG3TTY
121 	normf = tty.sg_flags;
122 #else
123 	normf = tty;
124 #endif
125 	ppid = getpid();
126 	/*
127 	 * Defend against d's, v's, w's, and a's in directories of
128 	 * path leading to our true name.
129 	 */
130 #ifndef	vms
131 	av[0] = tailpath(av[0]);
132 #else
133 	/*
134 	 * This program has to be invoked by using the following
135 	 * string definitions:
136 	 *
137 	 * vi == "$dir:ex.exe vi"
138 	 * view == "$dir:ex.exe view"
139 	 * ex == "$dir:ex.exe ex"
140 	 * edit == "$dir:ex.exe edit"
141 	 */
142 	ac--;
143 	av++;
144 #endif
145 
146 	/*
147 	 * Figure out how we were invoked: ex, edit, vi, view.
148 	 */
149 	ivis = any('v', av[0]);	/* "vi" */
150 	if (any('w', av[0]))	/* "view" */
151 		value(READONLY) = 1;
152 	if (any('d', av[0])) {	/* "edit" */
153 		value(OPEN) = 0;
154 		value(REPORT) = 1;
155 		value(MAGIC) = 0;
156 	}
157 
158 #ifdef EXSTRINGS
159 	/*
160 	 * For debugging take files out of . if name is a.out.
161 	 */
162 	if (av[0][0] == 'a')
163 		erpath = tailpath(erpath);
164 #endif
165 	/*
166 	 * Open the error message file.
167 	 */
168 	draino();
169 #ifdef EXSTRINGS
170 	erfile = open(erpath+4, 0);
171 	if (erfile < 0) {
172 		erfile = open(erpath, 0);
173 	}
174 #endif
175 	pstop();
176 
177 	/*
178 	 * Initialize interrupt handling.
179 	 */
180 	oldhup = signal(SIGHUP, SIG_IGN);
181 	if (oldhup == SIG_DFL)
182 		signal(SIGHUP, onhup);
183 	oldquit = signal(SIGQUIT, SIG_IGN);
184 	ruptible = signal(SIGINT, SIG_IGN) == SIG_DFL;
185 	if (signal(SIGTERM, SIG_IGN) == SIG_DFL)
186 		signal(SIGTERM, onhup);
187 	if (signal(SIGEMT, SIG_IGN) == SIG_DFL)
188 		signal(SIGEMT, onemt);
189 
190 	/*
191 	 * Process flag arguments.
192 	 */
193 	ac--, av++;
194 	while (ac && av[0][0] == '-') {
195 		c = av[0][1];
196 		if (c == 0) {
197 			hush = 1;
198 			value(AUTOPRINT) = 0;
199 			fast++;
200 		} else switch (c) {
201 
202 		case 'R':
203 			value(READONLY) = 1;
204 			break;
205 
206 #ifdef TRACE
207 		case 'T':
208 			if (av[0][2] == 0)
209 				tracef = "trace";
210 			else {
211 				tracef = tttrace;
212 				tracef[8] = av[0][2];
213 				if (tracef[8])
214 					tracef[9] = av[0][3];
215 				else
216 					tracef[9] = 0;
217 			}
218 			trace = fopen(tracef, "w");
219 #define tracbuf NULL
220 			if (trace == NULL)
221 				ex_printf("Trace create error\n");
222 			else
223 				setbuf(trace, tracbuf);
224 			break;
225 
226 #endif
227 
228 #ifdef LISPCODE
229 		case 'l':
230 			value(LISP) = 1;
231 			value(SHOWMATCH) = 1;
232 			break;
233 #endif
234 
235 		case 'r':
236 			recov++;
237 			break;
238 
239 		case 't':
240 			if (ac > 1 && av[1][0] != '-') {
241 				ac--, av++;
242 				itag = 1;
243 				/* BUG: should check for too long tag. */
244 				CP(lasttag, av[0]);
245 			}
246 			break;
247 
248 		case 'v':
249 			ivis = 1;
250 			break;
251 
252 		case 'w':
253 			defwind = 0;
254 			if (av[0][2] == 0) defwind = 3;
255 			else for (cp = &av[0][2]; isdigit(*cp); cp++)
256 				defwind = 10*defwind + *cp - '0';
257 			break;
258 
259 
260 		default:
261 			smerror("Unknown option %s\n", av[0]);
262 			break;
263 		}
264 		ac--, av++;
265 	}
266 
267 #ifdef SIGTSTP
268 	if (!hush && signal(SIGTSTP, SIG_IGN) == SIG_DFL)
269 		signal(SIGTSTP, onsusp), dosusp++;
270 #endif
271 
272 	if (ac && av[0][0] == '+') {
273 		firstpat = &av[0][1];
274 		ac--, av++;
275 	}
276 
277 
278 	/*
279 	 * If we are doing a recover and no filename
280 	 * was given, then execute an exrecover command with
281 	 * the -r option to type out the list of saved file names.
282 	 * Otherwise set the remembered file name to the first argument
283 	 * file name so the "recover" initial command will find it.
284 	 */
285 	if (recov) {
286 		if (ac == 0) {
287 			ppid = 0;
288 			setrupt();
289 			execl(EXRECOVER, "exrecover", "-r", 0);
290 			filioerr(EXRECOVER);
291 			ex_exit(1);
292 		}
293 		CP(savedfile, *av++), ac--;
294 	}
295 
296 	/*
297 	 * Initialize the argument list.
298 	 */
299 	argv0 = av;
300 	argc0 = ac;
301 	args0 = av[0];
302 	erewind();
303 
304 	/*
305 	 * Initialize a temporary file (buffer) and
306 	 * set up terminal environment.  Read user startup commands.
307 	 */
308 	if (setexit() == 0) {
309 		setrupt();
310 		intty = isatty(0);
311 		value(PROMPT) = intty;
312 #ifndef	vms
313 		if (cp = getenv("SHELL"))
314 #else
315 		if (cp = getlog("SHELL"))
316 #endif
317 			CP(shell, cp);
318 		if (fast || !intty)
319 			setterm("dumb");
320 		else {
321 			gettmode();
322 #ifndef	vms
323 			if ((cp = getenv("TERM")) != 0 && *cp)
324 				setterm(cp);
325 #else
326 			if ((cp = getlog("TERM")) != 0 && *cp) {
327 				/*
328 				 * Can't just use it directly since getlog
329 				 * returns a pointer to a static buffer that
330 				 * tgetent() will eventually use
331 				 */
332 				CP(termtype, cp);
333 				setterm(termtype);
334 			}
335 #endif
336 		}
337 	}
338 	if (setexit() == 0 && !fast && intty) {
339 #ifndef	vms
340 		if ((globp = getenv("EXINIT")) && *globp)
341 #else
342 		if ((globp = getlog("EXINIT")) && *globp)
343 #endif
344 			commands(1,1);
345 		else {
346 			globp = 0;
347 			if ((cp = getenv("HOME")) != 0 && *cp) {
348 				(void) strcat(strcpy(genbuf, cp), "/.exrc");
349 				if (iownit(genbuf))
350 					source(genbuf, 1);
351 			}
352 		}
353 		/*
354 		 * Allow local .exrc too.  This loses if . is $HOME,
355 		 * but nobody should notice unless they do stupid things
356 		 * like putting a version command in .exrc.  Besides,
357 		 * they should be using EXINIT, not .exrc, right?
358 		 */
359 		 if (iownit(".exrc"))
360 			source(".exrc", 1);
361 	}
362 #ifdef	UNIX_SBRK
363 	/*
364 	 * Initialize end of core pointers.
365 	 * Normally we avoid breaking back to fendcore after each
366 	 * file since this can be expensive (much core-core copying).
367 	 * If your system can scatter load processes you could do
368 	 * this as ed does, saving a little core, but it will probably
369 	 * not often make much difference.
370 	 */
371 	fendcore = (line *) sbrk(0);
372 	endcore = fendcore - 2;
373 #else
374 	/*
375 	 * Allocate all the memory we will ever use in one chunk.
376 	 * This is for system such as VMS where sbrk() does not
377 	 * guarantee that the memory allocated beyond the end is
378 	 * consecutive.  VMS's RMS does all sorts of memory allocation
379 	 * and screwed up ex royally because ex assumes that all
380 	 * memory up to "endcore" belongs to it and RMS has different
381 	 * ideas.
382 	 */
383 	fendcore = (line *) malloc((unsigned)
384 		value(LINELIMIT) * sizeof (line *));
385 	if (fendcore == NULL) {
386 		lprintf("ex: cannot handle %d lines\n", value(LINELIMIT));
387 		lprintf("ex: set \"linelimit\" lower\n");
388 		flush();
389 		ex_exit(1);
390 	}
391 	endcore = fendcore + (value(LINELIMIT) - 1);
392 #endif
393 	init();	/* moved after prev 2 chunks to fix directory option */
394 
395 	/*
396 	 * Initial processing.  Handle tag, recover, and file argument
397 	 * implied next commands.  If going in as 'vi', then don't do
398 	 * anything, just set initev so we will do it later (from within
399 	 * visual).
400 	 */
401 	if (setexit() == 0) {
402 		if (recov)
403 			globp = "recover";
404 		else if (itag)
405 			globp = ivis ? "tag" : "tag|p";
406 		else if (argc)
407 			globp = "next";
408 		if (ivis)
409 			initev = globp;
410 		else if (globp) {
411 			inglobal = 1;
412 			commands(1, 1);
413 			inglobal = 0;
414 		}
415 	}
416 
417 	/*
418 	 * Vi command... go into visual.
419 	 * Strange... everything in vi usually happens
420 	 * before we ever "start".
421 	 */
422 	if (ivis) {
423 		/*
424 		 * Don't have to be upward compatible with stupidity
425 		 * of starting editing at line $.
426 		 */
427 		if (dol > zero)
428 			dot = one;
429 		globp = "visual";
430 		if (setexit() == 0)
431 			commands(1, 1);
432 	}
433 
434 	/*
435 	 * Clear out trash in state accumulated by startup,
436 	 * and then do the main command loop for a normal edit.
437 	 * If you quit out of a 'vi' command by doing Q or ^\,
438 	 * you also fall through to here.
439 	 */
440 	seenprompt = 1;
441 	ungetchar(0);
442 	globp = 0;
443 	initev = 0;
444 	setlastchar('\n');
445 	setexit();
446 	commands(0, 0);
447 	cleanup(1);
448 	ex_exit(0);
449 }
450 
451 /*
452  * Initialization, before editing a new file.
453  * Main thing here is to get a new buffer (in fileinit),
454  * rest is peripheral state resetting.
455  */
456 init()
457 {
458 	register int i;
459 
460 	fileinit();
461 	dot = zero = truedol = unddol = dol = fendcore;
462 	one = zero+1;
463 	undkind = UNDNONE;
464 	chng = 0;
465 	edited = 0;
466 	for (i = 0; i <= 'z'-'a'+1; i++)
467 		names[i] = 1;
468 	anymarks = 0;
469 }
470 
471 /*
472  * Return last component of unix path name p.
473  */
474 char *
475 tailpath(p)
476 register char *p;
477 {
478 	register char *r;
479 
480 	for (r=p; *p; p++)
481 		if (*p == '/')
482 			r = p+1;
483 	return(r);
484 }
485 
486 /*
487  * Check ownership of file.  Return nonzero if it exists and is owned by the
488  * user or the option sourceany is used
489  */
490 iownit(file)
491 char *file;
492 {
493 	struct stat sb;
494 
495 	if (stat(file, &sb) == 0 && (value(SOURCEANY) || sb.st_uid == getuid()))
496 		return(1);
497 	else
498 		return(0);
499 }
500