Annotation of src/usr.bin/less/line.c, Revision 1.16
1.1 etheisen 1: /*
1.12 shadchin 2: * Copyright (C) 1984-2012 Mark Nudelman
1.14 nicm 3: * Modified for use with illumos by Garrett D'Amore.
4: * Copyright 2014 Garrett D'Amore <garrett@damore.org>
1.1 etheisen 5: *
1.5 millert 6: * You may distribute under the terms of either the GNU General Public
7: * License or the Less License, as specified in the README file.
1.1 etheisen 8: *
1.12 shadchin 9: * For more information, see the README file.
1.13 nicm 10: */
1.1 etheisen 11:
12: /*
13: * Routines to manipulate the "line buffer".
14: * The line buffer holds a line of output as it is being built
15: * in preparation for output to the screen.
16: */
17:
18: #include "less.h"
1.10 shadchin 19: #include "charset.h"
1.1 etheisen 20:
1.10 shadchin 21: static char *linebuf = NULL; /* Buffer which holds the current output line */
1.5 millert 22: static char *attr = NULL; /* Extension of linebuf to hold attributes */
1.13 nicm 23: int size_linebuf = 0; /* Size of line buffer (and attr buffer) */
1.5 millert 24:
1.10 shadchin 25: static int cshift; /* Current left-shift of output line buffer */
1.13 nicm 26: int hshift; /* Desired left-shift of output line buffer */
27: int tabstops[TABSTOP_MAX] = { 0 }; /* Custom tabstops */
28: int ntabstops = 1; /* Number of tabstops */
29: int tabdefault = 8; /* Default repeated tabstops */
30: off_t highest_hilite; /* Pos of last hilite in file found so far */
1.1 etheisen 31:
32: static int curr; /* Index into linebuf */
1.13 nicm 33: static int column; /* Printable length, accounting for backspaces, etc. */
1.1 etheisen 34: static int overstrike; /* Next char should overstrike previous char */
1.5 millert 35: static int last_overstrike = AT_NORMAL;
1.1 etheisen 36: static int is_null_line; /* There is no current line */
1.5 millert 37: static int lmargin; /* Left margin */
1.1 etheisen 38: static char pendc;
1.13 nicm 39: static off_t pendpos;
1.5 millert 40: static char *end_ansi_chars;
1.10 shadchin 41: static char *mid_ansi_chars;
1.1 etheisen 42:
1.13 nicm 43: static int attr_swidth(int);
44: static int attr_ewidth(int);
45: static int do_append(LWCHAR, char *, off_t);
1.1 etheisen 46:
1.11 millert 47: extern volatile sig_atomic_t sigs;
1.1 etheisen 48: extern int bs_mode;
49: extern int linenums;
50: extern int ctldisp;
51: extern int twiddle;
52: extern int binattr;
1.5 millert 53: extern int status_col;
1.1 etheisen 54: extern int auto_wrap, ignaw;
55: extern int bo_s_width, bo_e_width;
56: extern int ul_s_width, ul_e_width;
57: extern int bl_s_width, bl_e_width;
58: extern int so_s_width, so_e_width;
59: extern int sc_width, sc_height;
1.5 millert 60: extern int utf_mode;
1.13 nicm 61: extern off_t start_attnpos;
62: extern off_t end_attnpos;
1.5 millert 63:
1.10 shadchin 64: static char mbc_buf[MAX_UTF_CHAR_LEN];
65: static int mbc_buf_len = 0;
66: static int mbc_buf_index = 0;
1.13 nicm 67: static off_t mbc_pos;
1.10 shadchin 68:
1.5 millert 69: /*
70: * Initialize from environment variables.
71: */
1.13 nicm 72: void
73: init_line(void)
1.5 millert 74: {
75: end_ansi_chars = lgetenv("LESSANSIENDCHARS");
76: if (end_ansi_chars == NULL || *end_ansi_chars == '\0')
77: end_ansi_chars = "m";
1.10 shadchin 78:
79: mid_ansi_chars = lgetenv("LESSANSIMIDCHARS");
80: if (mid_ansi_chars == NULL || *mid_ansi_chars == '\0')
81: mid_ansi_chars = "0123456789;[?!\"'#%()*+ ";
82:
1.13 nicm 83: linebuf = ecalloc(LINEBUF_SIZE, sizeof (char));
84: attr = ecalloc(LINEBUF_SIZE, sizeof (char));
1.5 millert 85: size_linebuf = LINEBUF_SIZE;
86: }
87:
88: /*
89: * Expand the line buffer.
90: */
1.13 nicm 91: static int
92: expand_linebuf(void)
1.5 millert 93: {
1.10 shadchin 94: /* Double the size of the line buffer. */
1.7 millert 95: int new_size = size_linebuf * 2;
1.10 shadchin 96:
97: /* Just realloc to expand the buffer, if we can. */
1.13 nicm 98: char *new_buf = realloc(linebuf, new_size);
99: char *new_attr = realloc(attr, new_size);
100: if (new_buf == NULL || new_attr == NULL) {
1.15 mmcc 101: free(new_attr);
102: free(new_buf);
1.13 nicm 103: return (1);
1.5 millert 104: }
105: linebuf = new_buf;
106: attr = new_attr;
107: size_linebuf = new_size;
1.13 nicm 108: return (0);
1.5 millert 109: }
1.1 etheisen 110:
111: /*
1.10 shadchin 112: * Is a character ASCII?
113: */
1.13 nicm 114: int
115: is_ascii_char(LWCHAR ch)
1.10 shadchin 116: {
117: return (ch <= 0x7F);
118: }
119:
120: /*
1.1 etheisen 121: * Rewind the line buffer.
122: */
1.13 nicm 123: void
124: prewind(void)
1.1 etheisen 125: {
126: curr = 0;
127: column = 0;
1.10 shadchin 128: cshift = 0;
1.1 etheisen 129: overstrike = 0;
1.10 shadchin 130: last_overstrike = AT_NORMAL;
131: mbc_buf_len = 0;
1.1 etheisen 132: is_null_line = 0;
133: pendc = '\0';
1.5 millert 134: lmargin = 0;
135: if (status_col)
136: lmargin += 1;
1.1 etheisen 137: }
138:
139: /*
140: * Insert the line number (of the given position) into the line buffer.
141: */
1.13 nicm 142: void
143: plinenum(off_t pos)
1.1 etheisen 144: {
1.16 ! mmcc 145: off_t linenum = 0;
1.13 nicm 146: int i;
1.5 millert 147:
1.13 nicm 148: if (linenums == OPT_ONPLUS) {
1.5 millert 149: /*
150: * Get the line number and put it in the current line.
151: * {{ Note: since find_linenum calls forw_raw_line,
1.13 nicm 152: * it may seek in the input file, requiring the caller
1.5 millert 153: * of plinenum to re-seek if necessary. }}
154: * {{ Since forw_raw_line modifies linebuf, we must
155: * do this first, before storing anything in linebuf. }}
156: */
157: linenum = find_linenum(pos);
158: }
1.1 etheisen 159:
160: /*
1.5 millert 161: * Display a status column if the -J option is set.
1.1 etheisen 162: */
1.13 nicm 163: if (status_col) {
1.5 millert 164: linebuf[curr] = ' ';
1.13 nicm 165: if (start_attnpos != -1 &&
1.5 millert 166: pos >= start_attnpos && pos < end_attnpos)
1.10 shadchin 167: attr[curr] = AT_NORMAL|AT_HILITE;
1.5 millert 168: else
1.10 shadchin 169: attr[curr] = AT_NORMAL;
1.5 millert 170: curr++;
171: column++;
172: }
1.1 etheisen 173: /*
1.5 millert 174: * Display the line number at the start of each line
175: * if the -N option is set.
1.1 etheisen 176: */
1.13 nicm 177: if (linenums == OPT_ONPLUS) {
1.5 millert 178: char buf[INT_STRLEN_BOUND(pos) + 2];
179: int n;
1.1 etheisen 180:
1.13 nicm 181: linenumtoa(linenum, buf, sizeof (buf));
1.5 millert 182: n = strlen(buf);
183: if (n < MIN_LINENUM_WIDTH)
184: n = MIN_LINENUM_WIDTH;
1.6 millert 185: snprintf(linebuf+curr, size_linebuf-curr, "%*s ", n, buf);
1.5 millert 186: n++; /* One space after the line number. */
187: for (i = 0; i < n; i++)
188: attr[curr+i] = AT_NORMAL;
189: curr += n;
190: column += n;
191: lmargin += n;
192: }
1.1 etheisen 193:
194: /*
1.5 millert 195: * Append enough spaces to bring us to the lmargin.
1.1 etheisen 196: */
1.13 nicm 197: while (column < lmargin) {
1.1 etheisen 198: linebuf[curr] = ' ';
199: attr[curr++] = AT_NORMAL;
200: column++;
1.5 millert 201: }
202: }
203:
204: /*
1.10 shadchin 205: * Shift the input line left.
206: * This means discarding N printable chars at the start of the buffer.
1.5 millert 207: */
1.13 nicm 208: static void
209: pshift(int shift)
1.10 shadchin 210: {
211: LWCHAR prev_ch = 0;
212: unsigned char c;
213: int shifted = 0;
214: int to;
215: int from;
1.5 millert 216: int len;
1.10 shadchin 217: int width;
218: int prev_attr;
219: int next_attr;
220:
221: if (shift > column - lmargin)
222: shift = column - lmargin;
223: if (shift > curr - lmargin)
224: shift = curr - lmargin;
1.5 millert 225:
1.10 shadchin 226: to = from = lmargin;
1.5 millert 227: /*
1.10 shadchin 228: * We keep on going when shifted == shift
229: * to get all combining chars.
1.5 millert 230: */
1.13 nicm 231: while (shifted <= shift && from < curr) {
1.10 shadchin 232: c = linebuf[from];
1.13 nicm 233: if (ctldisp == OPT_ONPLUS && IS_CSI_START(c)) {
1.10 shadchin 234: /* Keep cumulative effect. */
235: linebuf[to] = c;
236: attr[to++] = attr[from++];
1.13 nicm 237: while (from < curr && linebuf[from]) {
1.10 shadchin 238: linebuf[to] = linebuf[from];
239: attr[to++] = attr[from];
240: if (!is_ansi_middle(linebuf[from++]))
241: break;
1.13 nicm 242: }
1.10 shadchin 243: continue;
244: }
245:
246: width = 0;
247:
1.13 nicm 248: if (!IS_ASCII_OCTET(c) && utf_mode) {
1.10 shadchin 249: /* Assumes well-formedness validation already done. */
250: LWCHAR ch;
251:
252: len = utf_len(c);
253: if (from + len > curr)
254: break;
255: ch = get_wchar(linebuf + from);
1.13 nicm 256: if (!is_composing_char(ch) &&
257: !is_combining_char(prev_ch, ch))
1.10 shadchin 258: width = is_wide_char(ch) ? 2 : 1;
259: prev_ch = ch;
1.13 nicm 260: } else {
1.10 shadchin 261: len = 1;
262: if (c == '\b')
263: /* XXX - Incorrect if several '\b' in a row. */
1.13 nicm 264: width = (utf_mode && is_wide_char(prev_ch)) ?
265: -2 : -1;
1.10 shadchin 266: else if (!control_char(c))
267: width = 1;
268: prev_ch = 0;
269: }
270:
271: if (width == 2 && shift - shifted == 1) {
272: /* Should never happen when called by pshift_all(). */
273: attr[to] = attr[from];
274: /*
275: * Assume a wide_char will never be the first half of a
276: * combining_char pair, so reset prev_ch in case we're
277: * followed by a '\b'.
278: */
279: prev_ch = linebuf[to++] = ' ';
280: from += len;
281: shifted++;
282: continue;
283: }
284:
285: /* Adjust width for magic cookies. */
286: prev_attr = (to > 0) ? attr[to-1] : AT_NORMAL;
287: next_attr = (from + len < curr) ? attr[from + len] : prev_attr;
1.13 nicm 288: if (!is_at_equiv(attr[from], prev_attr) &&
289: !is_at_equiv(attr[from], next_attr)) {
1.10 shadchin 290: width += attr_swidth(attr[from]);
291: if (from + len < curr)
292: width += attr_ewidth(attr[from]);
1.13 nicm 293: if (is_at_equiv(prev_attr, next_attr)) {
1.10 shadchin 294: width += attr_ewidth(prev_attr);
295: if (from + len < curr)
296: width += attr_swidth(next_attr);
1.5 millert 297: }
298: }
299:
1.10 shadchin 300: if (shift - shifted < width)
301: break;
302: from += len;
303: shifted += width;
304: if (shifted < 0)
305: shifted = 0;
306: }
1.13 nicm 307: while (from < curr) {
1.10 shadchin 308: linebuf[to] = linebuf[from];
309: attr[to++] = attr[from++];
310: }
311: curr = to;
312: column -= shifted;
313: cshift += shifted;
1.5 millert 314: }
315:
316: /*
1.10 shadchin 317: *
1.5 millert 318: */
1.13 nicm 319: void
320: pshift_all(void)
1.5 millert 321: {
1.10 shadchin 322: pshift(column);
1.1 etheisen 323: }
324:
325: /*
326: * Return the printing width of the start (enter) sequence
327: * for a given character attribute.
328: */
1.13 nicm 329: static int
330: attr_swidth(int a)
1.1 etheisen 331: {
1.10 shadchin 332: int w = 0;
333:
334: a = apply_at_specials(a);
335:
336: if (a & AT_UNDERLINE)
337: w += ul_s_width;
338: if (a & AT_BOLD)
339: w += bo_s_width;
340: if (a & AT_BLINK)
341: w += bl_s_width;
342: if (a & AT_STANDOUT)
343: w += so_s_width;
344:
1.13 nicm 345: return (w);
1.1 etheisen 346: }
347:
348: /*
349: * Return the printing width of the end (exit) sequence
350: * for a given character attribute.
351: */
1.13 nicm 352: static int
353: attr_ewidth(int a)
1.1 etheisen 354: {
1.10 shadchin 355: int w = 0;
356:
357: a = apply_at_specials(a);
358:
359: if (a & AT_UNDERLINE)
360: w += ul_e_width;
361: if (a & AT_BOLD)
362: w += bo_e_width;
363: if (a & AT_BLINK)
364: w += bl_e_width;
365: if (a & AT_STANDOUT)
366: w += so_e_width;
367:
1.13 nicm 368: return (w);
1.1 etheisen 369: }
370:
371: /*
372: * Return the printing width of a given character and attribute,
373: * if the character were added to the current position in the line buffer.
374: * Adding a character with a given attribute may cause an enter or exit
375: * attribute sequence to be inserted, so this must be taken into account.
376: */
1.13 nicm 377: static int
378: pwidth(LWCHAR ch, int a, LWCHAR prev_ch)
1.1 etheisen 379: {
1.10 shadchin 380: int w;
1.1 etheisen 381:
1.10 shadchin 382: if (ch == '\b')
1.1 etheisen 383: /*
1.10 shadchin 384: * Backspace moves backwards one or two positions.
385: * XXX - Incorrect if several '\b' in a row.
1.1 etheisen 386: */
1.13 nicm 387: return ((utf_mode && is_wide_char(prev_ch)) ? -2 : -1);
388:
389: if (!utf_mode || is_ascii_char(ch)) {
390: if (control_char((char)ch)) {
1.10 shadchin 391: /*
392: * Control characters do unpredictable things,
393: * so we don't even try to guess; say it doesn't move.
394: * This can only happen if the -r flag is in effect.
395: */
396: return (0);
397: }
1.13 nicm 398: } else {
399: if (is_composing_char(ch) || is_combining_char(prev_ch, ch)) {
1.10 shadchin 400: /*
401: * Composing and combining chars take up no space.
402: *
403: * Some terminals, upon failure to compose a
404: * composing character with the character(s) that
405: * precede(s) it will actually take up one column
406: * for the composing character; there isn't much
407: * we could do short of testing the (complex)
408: * composition process ourselves and printing
409: * a binary representation when it fails.
410: */
411: return (0);
412: }
413: }
1.1 etheisen 414:
415: /*
1.10 shadchin 416: * Other characters take one or two columns,
1.1 etheisen 417: * plus the width of any attribute enter/exit sequence.
418: */
419: w = 1;
1.10 shadchin 420: if (is_wide_char(ch))
421: w++;
422: if (curr > 0 && !is_at_equiv(attr[curr-1], a))
1.1 etheisen 423: w += attr_ewidth(attr[curr-1]);
1.10 shadchin 424: if ((apply_at_specials(a) != AT_NORMAL) &&
425: (curr == 0 || !is_at_equiv(attr[curr-1], a)))
1.1 etheisen 426: w += attr_swidth(a);
427: return (w);
428: }
429:
430: /*
1.10 shadchin 431: * Delete to the previous base character in the line buffer.
432: * Return 1 if one is found.
1.1 etheisen 433: */
1.13 nicm 434: static int
435: backc(void)
1.1 etheisen 436: {
1.10 shadchin 437: LWCHAR prev_ch;
438: char *p = linebuf + curr;
439: LWCHAR ch = step_char(&p, -1, linebuf + lmargin);
440: int width;
441:
442: /* This assumes that there is no '\b' in linebuf. */
1.13 nicm 443: while (curr > lmargin && column > lmargin &&
444: (!(attr[curr - 1] & (AT_ANSI|AT_BINARY)))) {
1.10 shadchin 445: curr = p - linebuf;
446: prev_ch = step_char(&p, -1, linebuf + lmargin);
447: width = pwidth(ch, attr[curr], prev_ch);
448: column -= width;
449: if (width > 0)
1.13 nicm 450: return (1);
1.10 shadchin 451: ch = prev_ch;
452: }
453:
1.13 nicm 454: return (0);
1.1 etheisen 455: }
456:
457: /*
1.5 millert 458: * Are we currently within a recognized ANSI escape sequence?
459: */
1.13 nicm 460: static int
461: in_ansi_esc_seq(void)
1.5 millert 462: {
1.10 shadchin 463: char *p;
1.5 millert 464:
465: /*
466: * Search backwards for either an ESC (which means we ARE in a seq);
467: * or an end char (which means we're NOT in a seq).
468: */
1.13 nicm 469: for (p = &linebuf[curr]; p > linebuf; ) {
1.10 shadchin 470: LWCHAR ch = step_char(&p, -1, linebuf);
471: if (IS_CSI_START(ch))
1.5 millert 472: return (1);
1.10 shadchin 473: if (!is_ansi_middle(ch))
1.5 millert 474: return (0);
475: }
476: return (0);
477: }
478:
479: /*
480: * Is a character the end of an ANSI escape sequence?
481: */
1.13 nicm 482: int
483: is_ansi_end(LWCHAR ch)
1.10 shadchin 484: {
485: if (!is_ascii_char(ch))
486: return (0);
1.13 nicm 487: return (strchr(end_ansi_chars, (char)ch) != NULL);
1.10 shadchin 488: }
489:
490: /*
491: *
492: */
1.13 nicm 493: int
494: is_ansi_middle(LWCHAR ch)
1.5 millert 495: {
1.10 shadchin 496: if (!is_ascii_char(ch))
497: return (0);
498: if (is_ansi_end(ch))
499: return (0);
1.13 nicm 500: return (strchr(mid_ansi_chars, (char)ch) != NULL);
1.5 millert 501: }
502:
503: /*
1.1 etheisen 504: * Append a character and attribute to the line buffer.
505: */
1.13 nicm 506: #define STORE_CHAR(ch, a, rep, pos) \
507: if (store_char((ch), (a), (rep), (pos))) \
508: return (1)
509:
510: static int
511: store_char(LWCHAR ch, char a, char *rep, off_t pos)
1.1 etheisen 512: {
1.10 shadchin 513: int w;
514: int replen;
515: char cs;
1.13 nicm 516: int matches;
1.10 shadchin 517:
518: w = (a & (AT_UNDERLINE|AT_BOLD)); /* Pre-use w. */
519: if (w != AT_NORMAL)
520: last_overstrike = w;
1.1 etheisen 521:
1.13 nicm 522: if (is_hilited(pos, pos+1, 0, &matches)) {
523: /*
524: * This character should be highlighted.
525: * Override the attribute passed in.
526: */
527: if (a != AT_ANSI) {
528: if (highest_hilite != -1 && pos > highest_hilite)
529: highest_hilite = pos;
530: a |= AT_HILITE;
1.10 shadchin 531: }
1.5 millert 532: }
1.10 shadchin 533:
1.13 nicm 534: if (ctldisp == OPT_ONPLUS && in_ansi_esc_seq()) {
1.10 shadchin 535: if (!is_ansi_end(ch) && !is_ansi_middle(ch)) {
536: /* Remove whole unrecognized sequence. */
537: char *p = &linebuf[curr];
538: LWCHAR bch;
539: do {
540: bch = step_char(&p, -1, linebuf);
541: } while (p > linebuf && !IS_CSI_START(bch));
542: curr = p - linebuf;
1.13 nicm 543: return (0);
1.10 shadchin 544: }
545: a = AT_ANSI; /* Will force re-AT_'ing around it. */
1.5 millert 546: w = 0;
1.13 nicm 547: } else if (ctldisp == OPT_ONPLUS && IS_CSI_START(ch)) {
1.10 shadchin 548: a = AT_ANSI; /* Will force re-AT_'ing around it. */
549: w = 0;
1.13 nicm 550: } else {
1.10 shadchin 551: char *p = &linebuf[curr];
552: LWCHAR prev_ch = step_char(&p, -1, linebuf);
553: w = pwidth(ch, a, prev_ch);
554: }
555:
1.5 millert 556: if (ctldisp != OPT_ON && column + w + attr_ewidth(a) > sc_width)
1.1 etheisen 557: /*
558: * Won't fit on screen.
559: */
560: return (1);
561:
1.13 nicm 562: if (rep == NULL) {
563: cs = (char)ch;
1.10 shadchin 564: rep = &cs;
565: replen = 1;
1.13 nicm 566: } else {
1.10 shadchin 567: replen = utf_len(rep[0]);
568: }
1.13 nicm 569: if (curr + replen >= size_linebuf-6) {
1.1 etheisen 570: /*
571: * Won't fit in line buffer.
1.5 millert 572: * Try to expand it.
1.1 etheisen 573: */
1.5 millert 574: if (expand_linebuf())
575: return (1);
576: }
1.1 etheisen 577:
1.13 nicm 578: while (replen-- > 0) {
1.10 shadchin 579: linebuf[curr] = *rep++;
580: attr[curr] = a;
581: curr++;
1.1 etheisen 582: }
583: column += w;
584: return (0);
585: }
586:
587: /*
1.5 millert 588: * Append a tab to the line buffer.
589: * Store spaces to represent the tab.
590: */
1.13 nicm 591: #define STORE_TAB(a, pos) \
592: if (store_tab((a), (pos))) \
593: return (1)
1.5 millert 594:
1.13 nicm 595: static int
596: store_tab(int attr, off_t pos)
1.5 millert 597: {
598: int to_tab = column + cshift - lmargin;
599: int i;
600:
601: if (ntabstops < 2 || to_tab >= tabstops[ntabstops-1])
602: to_tab = tabdefault -
1.13 nicm 603: ((to_tab - tabstops[ntabstops-1]) % tabdefault);
604: else {
1.5 millert 605: for (i = ntabstops - 2; i >= 0; i--)
606: if (to_tab >= tabstops[i])
607: break;
608: to_tab = tabstops[i+1] - to_tab;
609: }
610:
1.13 nicm 611: if (column + to_tab - 1 + pwidth(' ', attr, 0) +
612: attr_ewidth(attr) > sc_width)
613: return (1);
1.10 shadchin 614:
1.5 millert 615: do {
1.10 shadchin 616: STORE_CHAR(' ', attr, " ", pos);
1.5 millert 617: } while (--to_tab > 0);
1.13 nicm 618: return (0);
1.5 millert 619: }
620:
1.13 nicm 621: #define STORE_PRCHAR(c, pos) \
622: if (store_prchar((c), (pos))) \
623: return (1)
1.10 shadchin 624:
1.13 nicm 625: static int
626: store_prchar(char c, off_t pos)
1.10 shadchin 627: {
628: char *s;
629:
630: /*
631: * Convert to printable representation.
632: */
633: s = prchar(c);
634:
635: /*
636: * Make sure we can get the entire representation
637: * of the character on this line.
638: */
1.13 nicm 639: if (column + (int)strlen(s) - 1 +
640: pwidth(' ', binattr, 0) + attr_ewidth(binattr) > sc_width)
641: return (1);
1.10 shadchin 642:
1.13 nicm 643: for (; *s != 0; s++) {
1.10 shadchin 644: STORE_CHAR(*s, AT_BINARY, NULL, pos);
1.13 nicm 645: }
646: return (0);
1.10 shadchin 647: }
648:
1.13 nicm 649: static int
650: flush_mbc_buf(off_t pos)
1.10 shadchin 651: {
652: int i;
653:
654: for (i = 0; i < mbc_buf_index; i++)
655: if (store_prchar(mbc_buf[i], pos))
1.13 nicm 656: return (mbc_buf_index - i);
1.10 shadchin 657:
1.13 nicm 658: return (0);
1.10 shadchin 659: }
660:
1.5 millert 661: /*
1.1 etheisen 662: * Append a character to the line buffer.
663: * Expand tabs into spaces, handle underlining, boldfacing, etc.
664: * Returns 0 if ok, 1 if couldn't fit in buffer.
665: */
1.13 nicm 666: int
667: pappend(char c, off_t pos)
1.1 etheisen 668: {
1.5 millert 669: int r;
670:
1.13 nicm 671: if (pendc) {
1.10 shadchin 672: if (do_append(pendc, NULL, pendpos))
1.1 etheisen 673: /*
674: * Oops. We've probably lost the char which
675: * was in pendc, since caller won't back up.
676: */
677: return (1);
678: pendc = '\0';
679: }
680:
1.13 nicm 681: if (c == '\r' && bs_mode == BS_SPECIAL) {
682: if (mbc_buf_len > 0) /* utf_mode must be on. */ {
1.10 shadchin 683: /* Flush incomplete (truncated) sequence. */
684: r = flush_mbc_buf(mbc_pos);
685: mbc_buf_index = r + 1;
686: mbc_buf_len = 0;
687: if (r)
688: return (mbc_buf_index);
689: }
690:
1.1 etheisen 691: /*
1.13 nicm 692: * Don't put the CR into the buffer until we see
1.1 etheisen 693: * the next char. If the next char is a newline,
694: * discard the CR.
695: */
696: pendc = c;
697: pendpos = pos;
698: return (0);
699: }
700:
1.13 nicm 701: if (!utf_mode) {
1.10 shadchin 702: r = do_append((LWCHAR) c, NULL, pos);
1.13 nicm 703: } else {
1.10 shadchin 704: /* Perform strict validation in all possible cases. */
1.13 nicm 705: if (mbc_buf_len == 0) {
706: retry:
1.10 shadchin 707: mbc_buf_index = 1;
708: *mbc_buf = c;
1.13 nicm 709: if (IS_ASCII_OCTET(c)) {
1.10 shadchin 710: r = do_append((LWCHAR) c, NULL, pos);
1.13 nicm 711: } else if (IS_UTF8_LEAD(c)) {
1.10 shadchin 712: mbc_buf_len = utf_len(c);
713: mbc_pos = pos;
714: return (0);
1.13 nicm 715: } else {
1.10 shadchin 716: /* UTF8_INVALID or stray UTF8_TRAIL */
717: r = flush_mbc_buf(pos);
1.13 nicm 718: }
719: } else if (IS_UTF8_TRAIL(c)) {
1.10 shadchin 720: mbc_buf[mbc_buf_index++] = c;
721: if (mbc_buf_index < mbc_buf_len)
722: return (0);
723: if (is_utf8_well_formed(mbc_buf))
1.13 nicm 724: r = do_append(get_wchar(mbc_buf), mbc_buf,
725: mbc_pos);
1.10 shadchin 726: else
727: /* Complete, but not shortest form, sequence. */
728: mbc_buf_index = r = flush_mbc_buf(mbc_pos);
729: mbc_buf_len = 0;
1.13 nicm 730: } else {
1.10 shadchin 731: /* Flush incomplete (truncated) sequence. */
732: r = flush_mbc_buf(mbc_pos);
733: mbc_buf_index = r + 1;
734: mbc_buf_len = 0;
735: /* Handle new char. */
736: if (!r)
737: goto retry;
1.13 nicm 738: }
1.10 shadchin 739: }
740:
1.5 millert 741: /*
742: * If we need to shift the line, do it.
743: * But wait until we get to at least the middle of the screen,
744: * so shifting it doesn't affect the chars we're currently
745: * pappending. (Bold & underline can get messed up otherwise.)
746: */
1.13 nicm 747: if (cshift < hshift && column > sc_width / 2) {
1.5 millert 748: linebuf[curr] = '\0';
749: pshift(hshift - cshift);
750: }
1.13 nicm 751: if (r) {
1.10 shadchin 752: /* How many chars should caller back up? */
753: r = (!utf_mode) ? 1 : mbc_buf_index;
754: }
1.5 millert 755: return (r);
1.1 etheisen 756: }
757:
1.13 nicm 758: static int
759: do_append(LWCHAR ch, char *rep, off_t pos)
1.1 etheisen 760: {
1.13 nicm 761: int a;
1.10 shadchin 762: LWCHAR prev_ch;
1.1 etheisen 763:
1.10 shadchin 764: a = AT_NORMAL;
1.1 etheisen 765:
1.13 nicm 766: if (ch == '\b') {
1.10 shadchin 767: if (bs_mode == BS_CONTROL)
1.5 millert 768: goto do_control_char;
1.10 shadchin 769:
770: /*
771: * A better test is needed here so we don't
772: * backspace over part of the printed
773: * representation of a binary character.
774: */
1.13 nicm 775: if (curr <= lmargin ||
776: column <= lmargin ||
777: (attr[curr - 1] & (AT_ANSI|AT_BINARY))) {
1.10 shadchin 778: STORE_PRCHAR('\b', pos);
1.13 nicm 779: } else if (bs_mode == BS_NORMAL) {
1.10 shadchin 780: STORE_CHAR(ch, AT_NORMAL, NULL, pos);
1.13 nicm 781: } else if (bs_mode == BS_SPECIAL) {
1.10 shadchin 782: overstrike = backc();
1.13 nicm 783: }
1.10 shadchin 784:
1.13 nicm 785: return (0);
1.10 shadchin 786: }
787:
1.13 nicm 788: if (overstrike > 0) {
1.1 etheisen 789: /*
790: * Overstrike the character at the current position
1.13 nicm 791: * in the line buffer. This will cause either
792: * underline (if a "_" is overstruck),
1.1 etheisen 793: * bold (if an identical character is overstruck),
794: * or just deletion of the character in the buffer.
795: */
1.10 shadchin 796: overstrike = utf_mode ? -1 : 0;
797: /* To be correct, this must be a base character. */
798: prev_ch = get_wchar(linebuf + curr);
799: a = attr[curr];
1.13 nicm 800: if (ch == prev_ch) {
1.5 millert 801: /*
802: * Overstriking a char with itself means make it bold.
803: * But overstriking an underscore with itself is
804: * ambiguous. It could mean make it bold, or
805: * it could mean make it underlined.
806: * Use the previous overstrike to resolve it.
807: */
1.13 nicm 808: if (ch == '_') {
1.10 shadchin 809: if ((a & (AT_BOLD|AT_UNDERLINE)) != AT_NORMAL)
810: a |= (AT_BOLD|AT_UNDERLINE);
811: else if (last_overstrike != AT_NORMAL)
812: a |= last_overstrike;
813: else
814: a |= AT_BOLD;
1.13 nicm 815: } else {
1.10 shadchin 816: a |= AT_BOLD;
1.13 nicm 817: }
818: } else if (ch == '_') {
1.10 shadchin 819: a |= AT_UNDERLINE;
820: ch = prev_ch;
821: rep = linebuf + curr;
1.13 nicm 822: } else if (prev_ch == '_') {
1.10 shadchin 823: a |= AT_UNDERLINE;
824: }
825: /* Else we replace prev_ch, but we keep its attributes. */
1.13 nicm 826: } else if (overstrike < 0) {
827: if (is_composing_char(ch) ||
828: is_combining_char(get_wchar(linebuf + curr), ch))
1.10 shadchin 829: /* Continuation of the same overstrike. */
830: a = last_overstrike;
1.1 etheisen 831: else
1.10 shadchin 832: overstrike = 0;
833: }
834:
1.13 nicm 835: if (ch == '\t') {
1.5 millert 836: /*
837: * Expand a tab into spaces.
838: */
1.13 nicm 839: switch (bs_mode) {
1.1 etheisen 840: case BS_CONTROL:
841: goto do_control_char;
1.5 millert 842: case BS_NORMAL:
1.1 etheisen 843: case BS_SPECIAL:
1.10 shadchin 844: STORE_TAB(a, pos);
1.1 etheisen 845: break;
846: }
1.13 nicm 847: } else if ((!utf_mode || is_ascii_char(ch)) && control_char((char)ch)) {
848: do_control_char:
849: if (ctldisp == OPT_ON ||
850: (ctldisp == OPT_ONPLUS && IS_CSI_START(ch))) {
1.1 etheisen 851: /*
852: * Output as a normal character.
853: */
1.10 shadchin 854: STORE_CHAR(ch, AT_NORMAL, rep, pos);
1.13 nicm 855: } else {
856: STORE_PRCHAR((char)ch, pos);
1.10 shadchin 857: }
1.13 nicm 858: } else if (utf_mode && ctldisp != OPT_ON && is_ubin_char(ch)) {
1.10 shadchin 859: char *s;
860:
861: s = prutfchar(ch);
1.1 etheisen 862:
1.13 nicm 863: if (column + (int)strlen(s) - 1 +
1.10 shadchin 864: pwidth(' ', binattr, 0) + attr_ewidth(binattr) > sc_width)
865: return (1);
1.1 etheisen 866:
1.13 nicm 867: for (; *s != 0; s++)
1.10 shadchin 868: STORE_CHAR(*s, AT_BINARY, NULL, pos);
1.13 nicm 869: } else {
1.10 shadchin 870: STORE_CHAR(ch, a, rep, pos);
1.1 etheisen 871: }
1.13 nicm 872: return (0);
1.10 shadchin 873: }
874:
875: /*
876: *
877: */
1.13 nicm 878: int
879: pflushmbc(void)
1.10 shadchin 880: {
881: int r = 0;
1.1 etheisen 882:
1.13 nicm 883: if (mbc_buf_len > 0) {
1.10 shadchin 884: /* Flush incomplete (truncated) sequence. */
885: r = flush_mbc_buf(mbc_pos);
886: mbc_buf_len = 0;
887: }
1.13 nicm 888: return (r);
1.1 etheisen 889: }
890:
891: /*
892: * Terminate the line in the line buffer.
893: */
1.13 nicm 894: void
895: pdone(int endline, int forw)
1.1 etheisen 896: {
1.10 shadchin 897: (void) pflushmbc();
898:
1.1 etheisen 899: if (pendc && (pendc != '\r' || !endline))
900: /*
901: * If we had a pending character, put it in the buffer.
902: * But discard a pending CR if we are at end of line
903: * (that is, discard the CR in a CR/LF sequence).
904: */
1.10 shadchin 905: (void) do_append(pendc, NULL, pendpos);
1.1 etheisen 906:
907: /*
1.5 millert 908: * Make sure we've shifted the line, if we need to.
909: */
910: if (cshift < hshift)
911: pshift(hshift - cshift);
912:
1.13 nicm 913: if (ctldisp == OPT_ONPLUS && is_ansi_end('m')) {
1.10 shadchin 914: /* Switch to normal attribute at end of line. */
915: char *p = "\033[m";
1.13 nicm 916: for (; *p != '\0'; p++) {
1.10 shadchin 917: linebuf[curr] = *p;
918: attr[curr++] = AT_ANSI;
919: }
920: }
921:
1.5 millert 922: /*
1.1 etheisen 923: * Add a newline if necessary,
924: * and append a '\0' to the end of the line.
1.10 shadchin 925: * We output a newline if we're not at the right edge of the screen,
926: * or if the terminal doesn't auto wrap,
927: * or if this is really the end of the line AND the terminal ignores
928: * a newline at the right edge.
1.13 nicm 929: * (In the last case we don't want to output a newline if the terminal
1.10 shadchin 930: * doesn't ignore it since that would produce an extra blank line.
931: * But we do want to output a newline if the terminal ignores it in case
932: * the next line is blank. In that case the single newline output for
933: * that blank line would be ignored!)
1.1 etheisen 934: */
1.13 nicm 935: if (column < sc_width || !auto_wrap || (endline && ignaw) ||
936: ctldisp == OPT_ON) {
1.1 etheisen 937: linebuf[curr] = '\n';
938: attr[curr] = AT_NORMAL;
939: curr++;
1.13 nicm 940: } else if (ignaw && column >= sc_width && forw) {
1.10 shadchin 941: /*
942: * Terminals with "ignaw" don't wrap until they *really* need
943: * to, i.e. when the character *after* the last one to fit on a
944: * line is output. But they are too hard to deal with when they
945: * get in the state where a full screen width of characters
946: * have been output but the cursor is sitting on the right edge
947: * instead of at the start of the next line.
1.13 nicm 948: * So we nudge them into wrapping by outputting a space
949: * character plus a backspace. But do this only if moving
1.10 shadchin 950: * forward; if we're moving backward and drawing this line at
951: * the top of the screen, the space would overwrite the first
1.13 nicm 952: * char on the next line. We don't need to do this "nudge"
1.10 shadchin 953: * at the top of the screen anyway.
954: */
955: linebuf[curr] = ' ';
956: attr[curr++] = AT_NORMAL;
1.13 nicm 957: linebuf[curr] = '\b';
1.10 shadchin 958: attr[curr++] = AT_NORMAL;
1.1 etheisen 959: }
960: linebuf[curr] = '\0';
961: attr[curr] = AT_NORMAL;
1.10 shadchin 962: }
1.5 millert 963:
1.10 shadchin 964: /*
965: *
966: */
1.13 nicm 967: void
968: set_status_col(char c)
1.10 shadchin 969: {
970: linebuf[0] = c;
971: attr[0] = AT_NORMAL|AT_HILITE;
1.1 etheisen 972: }
973:
974: /*
975: * Get a character from the current line.
976: * Return the character as the function return value,
977: * and the character attribute in *ap.
978: */
1.13 nicm 979: int
980: gline(int i, int *ap)
1.1 etheisen 981: {
1.13 nicm 982: if (is_null_line) {
1.1 etheisen 983: /*
984: * If there is no current line, we pretend the line is
985: * either "~" or "", depending on the "twiddle" flag.
986: */
1.13 nicm 987: if (twiddle) {
988: if (i == 0) {
1.10 shadchin 989: *ap = AT_BOLD;
1.13 nicm 990: return ('~');
1.10 shadchin 991: }
992: --i;
993: }
994: /* Make sure we're back to AT_NORMAL before the '\n'. */
995: *ap = AT_NORMAL;
1.13 nicm 996: return (i ? '\0' : '\n');
1.1 etheisen 997: }
998:
999: *ap = attr[i];
1.10 shadchin 1000: return (linebuf[i] & 0xFF);
1.1 etheisen 1001: }
1002:
1003: /*
1004: * Indicate that there is no current line.
1005: */
1.13 nicm 1006: void
1007: null_line(void)
1.1 etheisen 1008: {
1009: is_null_line = 1;
1.5 millert 1010: cshift = 0;
1.1 etheisen 1011: }
1012:
1013: /*
1014: * Analogous to forw_line(), but deals with "raw lines":
1015: * lines which are not split for screen width.
1016: * {{ This is supposed to be more efficient than forw_line(). }}
1017: */
1.13 nicm 1018: off_t
1019: forw_raw_line(off_t curr_pos, char **linep, int *line_lenp)
1020: {
1021: int n;
1022: int c;
1023: off_t new_pos;
1024:
1025: if (curr_pos == -1 || ch_seek(curr_pos) ||
1026: (c = ch_forw_get()) == EOI)
1027: return (-1);
1.1 etheisen 1028:
1.5 millert 1029: n = 0;
1.13 nicm 1030: for (;;) {
1031: if (c == '\n' || c == EOI || ABORT_SIGS()) {
1.1 etheisen 1032: new_pos = ch_tell();
1033: break;
1034: }
1.13 nicm 1035: if (n >= size_linebuf-1) {
1036: if (expand_linebuf()) {
1.5 millert 1037: /*
1038: * Overflowed the input buffer.
1039: * Pretend the line ended here.
1040: */
1041: new_pos = ch_tell() - 1;
1042: break;
1043: }
1.1 etheisen 1044: }
1.13 nicm 1045: linebuf[n++] = (char)c;
1.1 etheisen 1046: c = ch_forw_get();
1047: }
1.5 millert 1048: linebuf[n] = '\0';
1.1 etheisen 1049: if (linep != NULL)
1050: *linep = linebuf;
1.10 shadchin 1051: if (line_lenp != NULL)
1052: *line_lenp = n;
1.1 etheisen 1053: return (new_pos);
1054: }
1055:
1056: /*
1057: * Analogous to back_line(), but deals with "raw lines".
1058: * {{ This is supposed to be more efficient than back_line(). }}
1059: */
1.13 nicm 1060: off_t
1061: back_raw_line(off_t curr_pos, char **linep, int *line_lenp)
1062: {
1063: int n;
1064: int c;
1065: off_t new_pos;
1066:
1067: if (curr_pos == -1 || curr_pos <= ch_zero() || ch_seek(curr_pos - 1))
1068: return (-1);
1.1 etheisen 1069:
1.5 millert 1070: n = size_linebuf;
1071: linebuf[--n] = '\0';
1.13 nicm 1072: for (;;) {
1.1 etheisen 1073: c = ch_back_get();
1.13 nicm 1074: if (c == '\n' || ABORT_SIGS()) {
1.1 etheisen 1075: /*
1076: * This is the newline ending the previous line.
1077: * We have hit the beginning of the line.
1078: */
1079: new_pos = ch_tell() + 1;
1080: break;
1081: }
1.13 nicm 1082: if (c == EOI) {
1.1 etheisen 1083: /*
1084: * We have hit the beginning of the file.
1085: * This must be the first line in the file.
1086: * This must, of course, be the beginning of the line.
1087: */
1088: new_pos = ch_zero();
1089: break;
1090: }
1.13 nicm 1091: if (n <= 0) {
1.5 millert 1092: int old_size_linebuf = size_linebuf;
1.13 nicm 1093: if (expand_linebuf()) {
1.5 millert 1094: /*
1095: * Overflowed the input buffer.
1096: * Pretend the line ended here.
1097: */
1098: new_pos = ch_tell() + 1;
1099: break;
1100: }
1.1 etheisen 1101: /*
1.5 millert 1102: * Shift the data to the end of the new linebuf.
1.1 etheisen 1103: */
1.5 millert 1104: n = size_linebuf - old_size_linebuf;
1.8 millert 1105: memmove(linebuf + n, linebuf, old_size_linebuf);
1.1 etheisen 1106: }
1.5 millert 1107: linebuf[--n] = c;
1.1 etheisen 1108: }
1109: if (linep != NULL)
1.5 millert 1110: *linep = &linebuf[n];
1.10 shadchin 1111: if (line_lenp != NULL)
1112: *line_lenp = size_linebuf - 1 - n;
1.1 etheisen 1113: return (new_pos);
1114: }
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