1 /* $OpenBSD: ex_txt.c,v 1.17 2020/04/30 10:40:21 millert Exp $ */
2
3 /*-
4 * Copyright (c) 1992, 1993, 1994
5 * The Regents of the University of California. All rights reserved.
6 * Copyright (c) 1992, 1993, 1994, 1995, 1996
7 * Keith Bostic. All rights reserved.
8 *
9 * See the LICENSE file for redistribution information.
10 */
11
12 #include "config.h"
13
14 #include <sys/types.h>
15 #include <sys/queue.h>
16
17 #include <bitstring.h>
18 #include <ctype.h>
19 #include <limits.h>
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <string.h>
23
24 #include "../common/common.h"
25 #include "../vi/vi.h"
26
27 /*
28 * !!!
29 * The backslash characters was special when it preceded a newline as part of
30 * a substitution replacement pattern. For example, the input ":a\<cr>" would
31 * failed immediately with an error, as the <cr> wasn't part of a substitution
32 * replacement pattern. This implies a frightening integration of the editor
33 * and the parser and/or the RE engine. There's no way I'm going to reproduce
34 * those semantics.
35 *
36 * So, if backslashes are special, this code inserts the backslash and the next
37 * character into the string, without regard for the character or the command
38 * being entered. Since "\<cr>" was illegal historically (except for the one
39 * special case), and the command will fail eventually, no historical scripts
40 * should break (presuming they didn't depend on the failure mode itself or the
41 * characters remaining when failure occurred.
42 */
43
44 static int txt_dent(SCR *, TEXT *);
45 static void txt_prompt(SCR *, TEXT *, CHAR_T, u_int32_t);
46
47 /*
48 * ex_txt --
49 * Get lines from the terminal for ex.
50 *
51 * PUBLIC: int ex_txt(SCR *, TEXTH *, CHAR_T, u_int32_t);
52 */
53 int
ex_txt(SCR * sp,TEXTH * tiqh,CHAR_T prompt,u_int32_t flags)54 ex_txt(SCR *sp, TEXTH *tiqh, CHAR_T prompt, u_int32_t flags)
55 {
56 EVENT ev;
57 GS *gp;
58 TEXT ait, *ntp, *tp;
59 carat_t carat_st;
60 size_t cnt;
61 int rval;
62
63 rval = 0;
64
65 /*
66 * Get a TEXT structure with some initial buffer space, reusing the
67 * last one if it's big enough. (All TEXT bookkeeping fields default
68 * to 0 -- text_init() handles this.)
69 */
70 if (!TAILQ_EMPTY(tiqh)) {
71 tp = TAILQ_FIRST(tiqh);
72 if (TAILQ_NEXT(tp, q) || tp->lb_len < 32) {
73 text_lfree(tiqh);
74 goto newtp;
75 }
76 tp->len = 0;
77 } else {
78 newtp: if ((tp = text_init(sp, NULL, 0, 32)) == NULL)
79 goto err;
80 TAILQ_INSERT_HEAD(tiqh, tp, q);
81 }
82
83 /* Set the starting line number. */
84 tp->lno = sp->lno + 1;
85
86 /*
87 * If it's a terminal, set up autoindent, put out the prompt, and
88 * set it up so we know we were suspended. Otherwise, turn off
89 * the autoindent flag, as that requires less special casing below.
90 *
91 * XXX
92 * Historic practice is that ^Z suspended command mode (but, because
93 * it ran in cooked mode, it was unaffected by the autowrite option.)
94 * On restart, any "current" input was discarded, whether in insert
95 * mode or not, and ex was in command mode. This code matches historic
96 * practice, but not 'cause it's easier.
97 */
98 gp = sp->gp;
99 if (F_ISSET(gp, G_SCRIPTED))
100 LF_CLR(TXT_AUTOINDENT);
101 else {
102 if (LF_ISSET(TXT_AUTOINDENT)) {
103 LF_SET(TXT_EOFCHAR);
104 if (v_txt_auto(sp, sp->lno, NULL, 0, tp))
105 goto err;
106 }
107 txt_prompt(sp, tp, prompt, flags);
108 }
109
110 for (carat_st = C_NOTSET;;) {
111 if (v_event_get(sp, &ev, 0, 0))
112 goto err;
113
114 /* Deal with all non-character events. */
115 switch (ev.e_event) {
116 case E_CHARACTER:
117 break;
118 case E_ERR:
119 goto err;
120 case E_REPAINT:
121 case E_WRESIZE:
122 continue;
123 case E_EOF:
124 rval = 1;
125 /* FALLTHROUGH */
126 case E_INTERRUPT:
127 /*
128 * Handle EOF/SIGINT events by discarding partially
129 * entered text and returning. EOF returns failure,
130 * E_INTERRUPT returns success.
131 */
132 goto notlast;
133 default:
134 v_event_err(sp, &ev);
135 goto notlast;
136 }
137
138 /*
139 * Deal with character events.
140 *
141 * Check to see if the character fits into the input buffer.
142 * (Use tp->len, ignore overwrite and non-printable chars.)
143 */
144 BINC_GOTO(sp, tp->lb, tp->lb_len, tp->len + 1);
145
146 switch (ev.e_value) {
147 case K_CR:
148 /*
149 * !!!
150 * Historically, <carriage-return>'s in the command
151 * weren't special, so the ex parser would return an
152 * unknown command error message. However, if they
153 * terminated the command if they were in a map. I'm
154 * pretty sure this still isn't right, but it handles
155 * what I've seen so far.
156 */
157 if (!F_ISSET(&ev.e_ch, CH_MAPPED))
158 goto ins_ch;
159 /* FALLTHROUGH */
160 case K_NL:
161 /*
162 * '\' can escape <carriage-return>/<newline>. We
163 * don't discard the backslash because we need it
164 * to get the <newline> through the ex parser.
165 */
166 if (LF_ISSET(TXT_BACKSLASH) &&
167 tp->len != 0 && tp->lb[tp->len - 1] == '\\')
168 goto ins_ch;
169
170 /*
171 * CR returns from the ex command line.
172 *
173 * XXX
174 * Terminate with a nul, needed by filter.
175 */
176 if (LF_ISSET(TXT_CR)) {
177 tp->lb[tp->len] = '\0';
178 goto done;
179 }
180
181 /*
182 * '.' may terminate text input mode; free the current
183 * TEXT.
184 */
185 if (LF_ISSET(TXT_DOTTERM) && tp->len == tp->ai + 1 &&
186 tp->lb[tp->len - 1] == '.') {
187 notlast: TAILQ_REMOVE(tiqh, tp, q);
188 text_free(tp);
189 goto done;
190 }
191
192 /* Set up bookkeeping for the new line. */
193 if ((ntp = text_init(sp, NULL, 0, 32)) == NULL)
194 goto err;
195 ntp->lno = tp->lno + 1;
196
197 /*
198 * Reset the autoindent line value. 0^D keeps the ai
199 * line from changing, ^D changes the level, even if
200 * there were no characters in the old line. Note, if
201 * using the current tp structure, use the cursor as
202 * the length, the autoindent characters may have been
203 * erased.
204 */
205 if (LF_ISSET(TXT_AUTOINDENT)) {
206 if (carat_st == C_NOCHANGE) {
207 if (v_txt_auto(sp,
208 OOBLNO, &ait, ait.ai, ntp))
209 goto err;
210 free(ait.lb);
211 } else
212 if (v_txt_auto(sp,
213 OOBLNO, tp, tp->len, ntp))
214 goto err;
215 carat_st = C_NOTSET;
216 }
217 txt_prompt(sp, ntp, prompt, flags);
218
219 /*
220 * Swap old and new TEXT's, and insert the new TEXT
221 * into the queue.
222 */
223 tp = ntp;
224 TAILQ_INSERT_TAIL(tiqh, tp, q);
225 break;
226 case K_CARAT: /* Delete autoindent chars. */
227 if (tp->len <= tp->ai && LF_ISSET(TXT_AUTOINDENT))
228 carat_st = C_CARATSET;
229 goto ins_ch;
230 case K_ZERO: /* Delete autoindent chars. */
231 if (tp->len <= tp->ai && LF_ISSET(TXT_AUTOINDENT))
232 carat_st = C_ZEROSET;
233 goto ins_ch;
234 case K_CNTRLD: /* Delete autoindent char. */
235 /*
236 * !!!
237 * Historically, the ^D command took (but then ignored)
238 * a count. For simplicity, we don't return it unless
239 * it's the first character entered. The check for len
240 * equal to 0 is okay, TXT_AUTOINDENT won't be set.
241 */
242 if (LF_ISSET(TXT_CNTRLD)) {
243 for (cnt = 0; cnt < tp->len; ++cnt)
244 if (!isblank(tp->lb[cnt]))
245 break;
246 if (cnt == tp->len) {
247 tp->len = 1;
248 tp->lb[0] = ev.e_c;
249 tp->lb[1] = '\0';
250
251 /*
252 * Put out a line separator, in case
253 * the command fails.
254 */
255 (void)putchar('\n');
256 goto done;
257 }
258 }
259
260 /*
261 * POSIX 1003.1b-1993, paragraph 7.1.1.9, states that
262 * the EOF characters are discarded if there are other
263 * characters to process in the line, i.e. if the EOF
264 * is not the first character in the line. For this
265 * reason, historic ex discarded the EOF characters,
266 * even if occurring in the middle of the input line.
267 * We match that historic practice.
268 *
269 * !!!
270 * The test for discarding in the middle of the line is
271 * done in the switch, because the CARAT forms are N+1,
272 * not N.
273 *
274 * !!!
275 * There's considerable magic to make the terminal code
276 * return the EOF character at all. See that code for
277 * details.
278 */
279 if (!LF_ISSET(TXT_AUTOINDENT) || tp->len == 0)
280 continue;
281 switch (carat_st) {
282 case C_CARATSET: /* ^^D */
283 if (tp->len > tp->ai + 1)
284 continue;
285
286 /* Save the ai string for later. */
287 ait.lb = NULL;
288 ait.lb_len = 0;
289 BINC_GOTO(sp, ait.lb, ait.lb_len, tp->ai);
290 memcpy(ait.lb, tp->lb, tp->ai);
291 ait.ai = ait.len = tp->ai;
292
293 carat_st = C_NOCHANGE;
294 goto leftmargin;
295 case C_ZEROSET: /* 0^D */
296 if (tp->len > tp->ai + 1)
297 continue;
298
299 carat_st = C_NOTSET;
300 leftmargin: (void)gp->scr_ex_adjust(sp, EX_TERM_CE);
301 tp->ai = tp->len = 0;
302 break;
303 case C_NOTSET: /* ^D */
304 if (tp->len > tp->ai)
305 continue;
306
307 if (txt_dent(sp, tp))
308 goto err;
309 break;
310 default:
311 abort();
312 }
313
314 /* Clear and redisplay the line. */
315 (void)gp->scr_ex_adjust(sp, EX_TERM_CE);
316 txt_prompt(sp, tp, prompt, flags);
317 break;
318 default:
319 /*
320 * See the TXT_BEAUTIFY comment in vi/v_txt_ev.c.
321 *
322 * Silently eliminate any iscntrl() character that was
323 * not already handled specially, except for <tab> and
324 * <ff>.
325 */
326 ins_ch: if (LF_ISSET(TXT_BEAUTIFY) && iscntrl(ev.e_c) &&
327 ev.e_value != K_FORMFEED && ev.e_value != K_TAB)
328 break;
329
330 tp->lb[tp->len++] = ev.e_c;
331 break;
332 }
333 }
334 /* NOTREACHED */
335
336 done: return (rval);
337
338 err:
339 alloc_err:
340 return (1);
341 }
342
343 /*
344 * txt_prompt --
345 * Display the ex prompt, line number, ai characters. Characters had
346 * better be printable by the terminal driver, but that's its problem,
347 * not ours.
348 */
349 static void
txt_prompt(SCR * sp,TEXT * tp,CHAR_T prompt,u_int32_t flags)350 txt_prompt(SCR *sp, TEXT *tp, CHAR_T prompt, u_int32_t flags)
351 {
352 /* Display the prompt. */
353 if (LF_ISSET(TXT_PROMPT))
354 (void)printf("%c", prompt);
355
356 /* Display the line number. */
357 if (LF_ISSET(TXT_NUMBER) && O_ISSET(sp, O_NUMBER))
358 (void)printf("%6lu ", (u_long)tp->lno);
359
360 /* Print out autoindent string. */
361 if (LF_ISSET(TXT_AUTOINDENT))
362 (void)printf("%.*s", (int)tp->ai, tp->lb);
363 (void)fflush(stdout);
364 }
365
366 /*
367 * txt_dent --
368 * Handle ^D outdents.
369 *
370 * Ex version of vi/v_ntext.c:txt_dent(). See that code for the (usual)
371 * ranting and raving. This is a fair bit simpler as ^T isn't special.
372 */
373 static int
txt_dent(SCR * sp,TEXT * tp)374 txt_dent(SCR *sp, TEXT *tp)
375 {
376 u_long sw, ts;
377 size_t cno, off, scno, spaces, tabs;
378
379 ts = O_VAL(sp, O_TABSTOP);
380 sw = O_VAL(sp, O_SHIFTWIDTH);
381
382 /* Get the current screen column. */
383 for (off = scno = 0; off < tp->len; ++off)
384 if (tp->lb[off] == '\t')
385 scno += COL_OFF(scno, ts);
386 else
387 ++scno;
388
389 /* Get the previous shiftwidth column. */
390 cno = scno--;
391 scno -= scno % sw;
392
393 /*
394 * Since we don't know what comes before the character(s) being
395 * deleted, we have to resolve the autoindent characters . The
396 * example is a <tab>, which doesn't take up a full shiftwidth
397 * number of columns because it's preceded by <space>s. This is
398 * easy to get if the user sets shiftwidth to a value less than
399 * tabstop, and then uses ^T to indent, and ^D to outdent.
400 *
401 * Count up spaces/tabs needed to get to the target.
402 */
403 cno = 0;
404 tabs = 0;
405 if (!O_ISSET(sp, O_EXPANDTAB)) {
406 for (; cno + COL_OFF(cno, ts) <= scno; ++tabs)
407 cno += COL_OFF(cno, ts);
408 }
409 spaces = scno - cno;
410
411 /* Make sure there's enough room. */
412 BINC_RET(sp, tp->lb, tp->lb_len, tabs + spaces + 1);
413
414 /* Adjust the final ai character count. */
415 tp->ai = tabs + spaces;
416
417 /* Enter the replacement characters. */
418 for (tp->len = 0; tabs > 0; --tabs)
419 tp->lb[tp->len++] = '\t';
420 for (; spaces > 0; --spaces)
421 tp->lb[tp->len++] = ' ';
422 return (0);
423 }
424