xref: /original-bsd/usr.bin/ex/ex.c (revision 5b560bbe)
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	7.7.1.1 (Berkeley) 10/21/90";
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 #include "pathnames.h"
22 
23 #ifdef TRACE
24 #ifdef	vms
25 char	tttrace[]	= { 't','r','a','c','e','.','l','i','s' };
26 #else
27 char	tttrace[]	= { '/','d','e','v','/','t','t','y','x','x',0 };
28 #endif
29 #endif
30 
31 /*
32  * The code for ex is divided as follows:
33  *
34  * ex.c			Entry point and routines handling interrupt, hangup
35  *			signals; initialization code.
36  *
37  * ex_addr.c		Address parsing routines for command mode decoding.
38  *			Routines to set and check address ranges on commands.
39  *
40  * ex_cmds.c		Command mode command decoding.
41  *
42  * ex_cmds2.c		Subroutines for command decoding and processing of
43  *			file names in the argument list.  Routines to print
44  *			messages and reset state when errors occur.
45  *
46  * ex_cmdsub.c		Subroutines which implement command mode functions
47  *			such as append, delete, join.
48  *
49  * ex_data.c		Initialization of options.
50  *
51  * ex_get.c		Command mode input routines.
52  *
53  * ex_io.c		General input/output processing: file i/o, unix
54  *			escapes, filtering, source commands, preserving
55  *			and recovering.
56  *
57  * ex_put.c		Terminal driving and optimizing routines for low-level
58  *			output (cursor-positioning); output line formatting
59  *			routines.
60  *
61  * ex_re.c		Global commands, substitute, regular expression
62  *			compilation and execution.
63  *
64  * ex_set.c		The set command.
65  *
66  * ex_subr.c		Loads of miscellaneous subroutines.
67  *
68  * ex_temp.c		Editor buffer routines for main buffer and also
69  *			for named buffers (Q registers if you will.)
70  *
71  * ex_tty.c		Terminal dependent initializations from termcap
72  *			data base, grabbing of tty modes (at beginning
73  *			and after escapes).
74  *
75  * ex_unix.c		Routines for the ! command and its variations.
76  *
77  * ex_v*.c		Visual/open mode routines... see ex_v.c for a
78  *			guide to the overall organization.
79  */
80 
81 /*
82  * Main procedure.  Process arguments and then
83  * transfer control to the main command processing loop
84  * in the routine commands.  We are entered as either "ex", "edit", "vi"
85  * or "view" and the distinction is made here.  Actually, we are "vi" if
86  * there is a 'v' in our name, "view" is there is a 'w', and "edit" if
87  * there is a 'd' in our name.  For edit we just diddle options;
88  * for vi we actually force an early visual command.
89  */
90 main(ac, av)
91 	register int ac;
92 	register char *av[];
93 {
94 #ifdef EXSTRINGS
95 	char *erpath = EXSTRINGS;
96 #endif
97 	register char *cp;
98 	register int c;
99 	bool recov = 0;
100 	bool ivis;
101 	bool itag = 0;
102 	bool fast = 0;
103 	extern int onemt();
104 #ifdef UNIX_SBRK
105 	extern char *sbrk();
106 #else
107 	extern char *malloc();
108 #endif
109 #ifdef TRACE
110 	register char *tracef;
111 #endif
112 #ifdef	vms
113 	char termtype[20];
114 #endif
115 
116 	/*
117 	 * Immediately grab the tty modes so that we wont
118 	 * get messed up if an interrupt comes in quickly.
119 	 */
120 	ex_gTTY(1);
121 #ifndef USG3TTY
122 	normf = tty.sg_flags;
123 #else
124 	normf = tty;
125 #endif
126 	ppid = getpid();
127 	/*
128 	 * Defend against d's, v's, w's, and a's in directories of
129 	 * path leading to our true name.
130 	 */
131 #ifndef	vms
132 	av[0] = tailpath(av[0]);
133 #else
134 	/*
135 	 * This program has to be invoked by using the following
136 	 * string definitions:
137 	 *
138 	 * vi == "$dir:ex.exe vi"
139 	 * view == "$dir:ex.exe view"
140 	 * ex == "$dir:ex.exe ex"
141 	 * edit == "$dir:ex.exe edit"
142 	 */
143 	ac--;
144 	av++;
145 #endif
146 
147 	/*
148 	 * Figure out how we were invoked: ex, edit, vi, view.
149 	 */
150 	ivis = any('v', av[0]);	/* "vi" */
151 	if (any('w', av[0]))	/* "view" */
152 		value(READONLY) = 1;
153 	if (any('d', av[0])) {	/* "edit" */
154 		value(OPEN) = 0;
155 		value(REPORT) = 1;
156 		value(MAGIC) = 0;
157 	}
158 
159 #ifdef EXSTRINGS
160 	/*
161 	 * For debugging take files out of . if name is a.out.
162 	 */
163 	if (av[0][0] == 'a')
164 		erpath = tailpath(erpath);
165 #endif
166 	/*
167 	 * Open the error message file.
168 	 */
169 	draino();
170 #ifdef EXSTRINGS
171 	erfile = open(erpath+4, 0);
172 	if (erfile < 0) {
173 		erfile = open(erpath, 0);
174 	}
175 #endif
176 	pstop();
177 
178 	/*
179 	 * Initialize interrupt handling.
180 	 */
181 	oldhup = signal(SIGHUP, SIG_IGN);
182 	if (oldhup == SIG_DFL)
183 		signal(SIGHUP, onhup);
184 	oldquit = signal(SIGQUIT, SIG_IGN);
185 	ruptible = signal(SIGINT, SIG_IGN) == SIG_DFL;
186 	if (signal(SIGTERM, SIG_IGN) == SIG_DFL)
187 		signal(SIGTERM, onhup);
188 	if (signal(SIGEMT, SIG_IGN) == SIG_DFL)
189 		signal(SIGEMT, onemt);
190 
191 	/*
192 	 * Process flag arguments.
193 	 */
194 	ac--, av++;
195 	while (ac && av[0][0] == '-') {
196 		c = av[0][1];
197 		if (c == 0) {
198 			hush = 1;
199 			value(AUTOPRINT) = 0;
200 			fast++;
201 		} else switch (c) {
202 
203 		case 'R':
204 			value(READONLY) = 1;
205 			break;
206 
207 #ifdef TRACE
208 		case 'T':
209 			if (av[0][2] == 0)
210 				tracef = "trace";
211 			else {
212 				tracef = tttrace;
213 				tracef[8] = av[0][2];
214 				if (tracef[8])
215 					tracef[9] = av[0][3];
216 				else
217 					tracef[9] = 0;
218 			}
219 			trace = fopen(tracef, "w");
220 #define tracbuf NULL
221 			if (trace == NULL)
222 				ex_printf("Trace create error\n");
223 			else
224 				setbuf(trace, tracbuf);
225 			break;
226 
227 #endif
228 
229 #ifdef LISPCODE
230 		case 'l':
231 			value(LISP) = 1;
232 			value(SHOWMATCH) = 1;
233 			break;
234 #endif
235 
236 		case 'r':
237 			recov++;
238 			break;
239 
240 		case 't':
241 			if (ac > 1 && av[1][0] != '-') {
242 				ac--, av++;
243 				itag = 1;
244 				/* BUG: should check for too long tag. */
245 				CP(lasttag, av[0]);
246 			}
247 			break;
248 
249 		case 'v':
250 			ivis = 1;
251 			break;
252 
253 		case 'w':
254 			defwind = 0;
255 			if (av[0][2] == 0) defwind = 3;
256 			else for (cp = &av[0][2]; isdigit(*cp); cp++)
257 				defwind = 10*defwind + *cp - '0';
258 			break;
259 
260 
261 		default:
262 			smerror("Unknown option %s\n", av[0]);
263 			break;
264 		}
265 		ac--, av++;
266 	}
267 
268 #ifdef SIGTSTP
269 	if (!hush && signal(SIGTSTP, SIG_IGN) == SIG_DFL)
270 		signal(SIGTSTP, onsusp), dosusp++;
271 #endif
272 
273 	if (ac && av[0][0] == '+') {
274 		firstpat = &av[0][1];
275 		ac--, av++;
276 	}
277 
278 
279 	/*
280 	 * If we are doing a recover and no filename
281 	 * was given, then execute an exrecover command with
282 	 * the -r option to type out the list of saved file names.
283 	 * Otherwise set the remembered file name to the first argument
284 	 * file name so the "recover" initial command will find it.
285 	 */
286 	if (recov) {
287 		if (ac == 0) {
288 			ppid = 0;
289 			setrupt();
290 			execl(_PATH_EXRECOVER, "exrecover", "-r", 0);
291 			filioerr(_PATH_EXRECOVER);
292 			ex_exit(1);
293 		}
294 		CP(savedfile, *av++), ac--;
295 	}
296 
297 	/*
298 	 * Initialize the argument list.
299 	 */
300 	argv0 = av;
301 	argc0 = ac;
302 	args0 = av[0];
303 	erewind();
304 
305 	/*
306 	 * Initialize a temporary file (buffer) and
307 	 * set up terminal environment.  Read user startup commands.
308 	 */
309 	if (setexit() == 0) {
310 		setrupt();
311 		intty = isatty(0);
312 		value(PROMPT) = intty;
313 #ifndef	vms
314 		if (cp = getenv("SHELL"))
315 #else
316 		if (cp = getlog("SHELL"))
317 #endif
318 			CP(shell, cp);
319 		if (fast || !intty)
320 			setterm("dumb");
321 		else {
322 			gettmode();
323 #ifndef	vms
324 			if ((cp = getenv("TERM")) != 0 && *cp)
325 				setterm(cp);
326 #else
327 			if ((cp = getlog("TERM")) != 0 && *cp) {
328 				/*
329 				 * Can't just use it directly since getlog
330 				 * returns a pointer to a static buffer that
331 				 * tgetent() will eventually use
332 				 */
333 				CP(termtype, cp);
334 				setterm(termtype);
335 			}
336 #endif
337 		}
338 	}
339 	if (setexit() == 0 && !fast && intty) {
340 #ifndef	vms
341 		if ((globp = getenv("EXINIT")) && *globp)
342 #else
343 		if ((globp = getlog("EXINIT")) && *globp)
344 #endif
345 			commands(1,1);
346 		else {
347 			globp = 0;
348 			if ((cp = getenv("HOME")) != 0 && *cp) {
349 				(void) strcat(strcpy(genbuf, cp), "/.exrc");
350 				if (iownit(genbuf))
351 					source(genbuf, 1);
352 			}
353 		}
354 		/*
355 		 * Allow local .exrc too.  This loses if . is $HOME,
356 		 * but nobody should notice unless they do stupid things
357 		 * like putting a version command in .exrc.  Besides,
358 		 * they should be using EXINIT, not .exrc, right?
359 		 */
360 		 if (iownit(".exrc"))
361 			source(".exrc", 1);
362 	}
363 #ifdef	UNIX_SBRK
364 	/*
365 	 * Initialize end of core pointers.
366 	 * Normally we avoid breaking back to fendcore after each
367 	 * file since this can be expensive (much core-core copying).
368 	 * If your system can scatter load processes you could do
369 	 * this as ed does, saving a little core, but it will probably
370 	 * not often make much difference.
371 	 */
372 	fendcore = (line *) sbrk(0);
373 	endcore = fendcore - 2;
374 #else
375 	/*
376 	 * Allocate all the memory we will ever use in one chunk.
377 	 * This is for system such as VMS where sbrk() does not
378 	 * guarantee that the memory allocated beyond the end is
379 	 * consecutive.  VMS's RMS does all sorts of memory allocation
380 	 * and screwed up ex royally because ex assumes that all
381 	 * memory up to "endcore" belongs to it and RMS has different
382 	 * ideas.
383 	 */
384 	fendcore = (line *) malloc((unsigned)
385 		value(LINELIMIT) * sizeof (line *));
386 	if (fendcore == NULL) {
387 		lprintf("ex: cannot handle %d lines\n", value(LINELIMIT));
388 		lprintf("ex: set \"linelimit\" lower\n");
389 		flush();
390 		ex_exit(1);
391 	}
392 	endcore = fendcore + (value(LINELIMIT) - 1);
393 #endif
394 	init();	/* moved after prev 2 chunks to fix directory option */
395 
396 	/*
397 	 * Initial processing.  Handle tag, recover, and file argument
398 	 * implied next commands.  If going in as 'vi', then don't do
399 	 * anything, just set initev so we will do it later (from within
400 	 * visual).
401 	 */
402 	if (setexit() == 0) {
403 		if (recov)
404 			globp = "recover";
405 		else if (itag)
406 			globp = ivis ? "tag" : "tag|p";
407 		else if (argc)
408 			globp = "next";
409 		if (ivis)
410 			initev = globp;
411 		else if (globp) {
412 			inglobal = 1;
413 			commands(1, 1);
414 			inglobal = 0;
415 		}
416 	}
417 
418 	/*
419 	 * Vi command... go into visual.
420 	 * Strange... everything in vi usually happens
421 	 * before we ever "start".
422 	 */
423 	if (ivis) {
424 		/*
425 		 * Don't have to be upward compatible with stupidity
426 		 * of starting editing at line $.
427 		 */
428 		if (dol > zero)
429 			dot = one;
430 		globp = "visual";
431 		if (setexit() == 0)
432 			commands(1, 1);
433 	}
434 
435 	/*
436 	 * Clear out trash in state accumulated by startup,
437 	 * and then do the main command loop for a normal edit.
438 	 * If you quit out of a 'vi' command by doing Q or ^\,
439 	 * you also fall through to here.
440 	 */
441 	seenprompt = 1;
442 	ungetchar(0);
443 	globp = 0;
444 	initev = 0;
445 	setlastchar('\n');
446 	setexit();
447 	commands(0, 0);
448 	cleanup(1);
449 	ex_exit(0);
450 }
451 
452 /*
453  * Initialization, before editing a new file.
454  * Main thing here is to get a new buffer (in fileinit),
455  * rest is peripheral state resetting.
456  */
457 init()
458 {
459 	register int i;
460 
461 	fileinit();
462 	dot = zero = truedol = unddol = dol = fendcore;
463 	one = zero+1;
464 	undkind = UNDNONE;
465 	chng = 0;
466 	edited = 0;
467 	for (i = 0; i <= 'z'-'a'+1; i++)
468 		names[i] = 1;
469 	anymarks = 0;
470 }
471 
472 /*
473  * Return last component of unix path name p.
474  */
475 char *
476 tailpath(p)
477 register char *p;
478 {
479 	register char *r;
480 
481 	for (r=p; *p; p++)
482 		if (*p == '/')
483 			r = p+1;
484 	return(r);
485 }
486 
487 /*
488  * Check ownership of file.  Return nonzero if it exists and is owned by the
489  * user or the option sourceany is used
490  */
491 iownit(file)
492 char *file;
493 {
494 	struct stat sb;
495 
496 	if (stat(file, &sb) == 0 && (value(SOURCEANY) || sb.st_uid == getuid()))
497 		return(1);
498 	else
499 		return(0);
500 }
501