st

Suckless' st with my personal patches
git clone https://git.instinctive.eu/st.git
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st.c (58244B)


      1 /* See LICENSE for license details. */
      2 #include <ctype.h>
      3 #include <errno.h>
      4 #include <fcntl.h>
      5 #include <limits.h>
      6 #include <pwd.h>
      7 #include <stdarg.h>
      8 #include <stdio.h>
      9 #include <stdlib.h>
     10 #include <string.h>
     11 #include <signal.h>
     12 #include <sys/ioctl.h>
     13 #include <sys/select.h>
     14 #include <sys/types.h>
     15 #include <sys/wait.h>
     16 #include <termios.h>
     17 #include <unistd.h>
     18 #include <wchar.h>
     19 
     20 #include "st.h"
     21 #include "win.h"
     22 
     23 #if   defined(__linux)
     24  #include <pty.h>
     25 #elif defined(__OpenBSD__) || defined(__NetBSD__) || defined(__APPLE__)
     26  #include <util.h>
     27 #elif defined(__FreeBSD__) || defined(__DragonFly__)
     28  #include <libutil.h>
     29 #endif
     30 
     31 /* Arbitrary sizes */
     32 #define UTF_INVALID   0xFFFD
     33 #define UTF_SIZ       4
     34 #define ESC_BUF_SIZ   (128*UTF_SIZ)
     35 #define ESC_ARG_SIZ   16
     36 #define STR_BUF_SIZ   ESC_BUF_SIZ
     37 #define STR_ARG_SIZ   ESC_ARG_SIZ
     38 
     39 /* macros */
     40 #define IS_SET(flag)		((term.mode & (flag)) != 0)
     41 #define ISCONTROLC0(c)		(BETWEEN(c, 0, 0x1f) || (c) == 0x7f)
     42 #define ISCONTROLC1(c)		(BETWEEN(c, 0x80, 0x9f))
     43 #define ISCONTROL(c)		(ISCONTROLC0(c) || ISCONTROLC1(c))
     44 #define ISDELIM(u)		(u && wcschr(worddelimiters, u))
     45 
     46 enum term_mode {
     47 	MODE_WRAP        = 1 << 0,
     48 	MODE_INSERT      = 1 << 1,
     49 	MODE_ALTSCREEN   = 1 << 2,
     50 	MODE_CRLF        = 1 << 3,
     51 	MODE_ECHO        = 1 << 4,
     52 	MODE_PRINT       = 1 << 5,
     53 	MODE_UTF8        = 1 << 6,
     54 };
     55 
     56 enum cursor_movement {
     57 	CURSOR_SAVE,
     58 	CURSOR_LOAD
     59 };
     60 
     61 enum cursor_state {
     62 	CURSOR_DEFAULT  = 0,
     63 	CURSOR_WRAPNEXT = 1,
     64 	CURSOR_ORIGIN   = 2
     65 };
     66 
     67 enum charset {
     68 	CS_GRAPHIC0,
     69 	CS_GRAPHIC1,
     70 	CS_UK,
     71 	CS_USA,
     72 	CS_MULTI,
     73 	CS_GER,
     74 	CS_FIN
     75 };
     76 
     77 enum escape_state {
     78 	ESC_START      = 1,
     79 	ESC_CSI        = 2,
     80 	ESC_STR        = 4,  /* DCS, OSC, PM, APC */
     81 	ESC_ALTCHARSET = 8,
     82 	ESC_STR_END    = 16, /* a final string was encountered */
     83 	ESC_TEST       = 32, /* Enter in test mode */
     84 	ESC_UTF8       = 64,
     85 };
     86 
     87 typedef struct {
     88 	Glyph attr; /* current char attributes */
     89 	int x;
     90 	int y;
     91 	char state;
     92 } TCursor;
     93 
     94 typedef struct {
     95 	int mode;
     96 	int type;
     97 	int snap;
     98 	/*
     99 	 * Selection variables:
    100 	 * nb – normalized coordinates of the beginning of the selection
    101 	 * ne – normalized coordinates of the end of the selection
    102 	 * ob – original coordinates of the beginning of the selection
    103 	 * oe – original coordinates of the end of the selection
    104 	 */
    105 	struct {
    106 		int x, y;
    107 	} nb, ne, ob, oe;
    108 
    109 	int alt;
    110 } Selection;
    111 
    112 /* Internal representation of the screen */
    113 typedef struct {
    114 	int row;      /* nb row */
    115 	int col;      /* nb col */
    116 	Line *line;   /* screen */
    117 	Line *alt;    /* alternate screen */
    118 	int *dirty;   /* dirtyness of lines */
    119 	TCursor c;    /* cursor */
    120 	int ocx;      /* old cursor col */
    121 	int ocy;      /* old cursor row */
    122 	int top;      /* top    scroll limit */
    123 	int bot;      /* bottom scroll limit */
    124 	int mode;     /* terminal mode flags */
    125 	int esc;      /* escape state flags */
    126 	char trantbl[4]; /* charset table translation */
    127 	int charset;  /* current charset */
    128 	int icharset; /* selected charset for sequence */
    129 	int *tabs;
    130 	Rune lastc;   /* last printed char outside of sequence, 0 if control */
    131 } Term;
    132 
    133 /* CSI Escape sequence structs */
    134 /* ESC '[' [[ [<priv>] <arg> [;]] <mode> [<mode>]] */
    135 typedef struct {
    136 	char buf[ESC_BUF_SIZ]; /* raw string */
    137 	size_t len;            /* raw string length */
    138 	char priv;
    139 	int arg[ESC_ARG_SIZ];
    140 	int narg;              /* nb of args */
    141 	char mode[2];
    142 } CSIEscape;
    143 
    144 /* STR Escape sequence structs */
    145 /* ESC type [[ [<priv>] <arg> [;]] <mode>] ESC '\' */
    146 typedef struct {
    147 	char type;             /* ESC type ... */
    148 	char *buf;             /* allocated raw string */
    149 	size_t siz;            /* allocation size */
    150 	size_t len;            /* raw string length */
    151 	char *args[STR_ARG_SIZ];
    152 	int narg;              /* nb of args */
    153 } STREscape;
    154 
    155 static void execsh(char *, char **);
    156 static void stty(char **);
    157 static void sigchld(int);
    158 static void ttywriteraw(const char *, size_t);
    159 
    160 static void csidump(void);
    161 static void csihandle(void);
    162 static void csiparse(void);
    163 static void csireset(void);
    164 static void osc_color_response(int, int, int);
    165 static int eschandle(uchar);
    166 static void strdump(void);
    167 static void strhandle(void);
    168 static void strparse(void);
    169 static void strreset(void);
    170 
    171 static void tprinter(char *, size_t);
    172 static void tdumpsel(void);
    173 static void tdumpline(int);
    174 static void tdump(void);
    175 static void tclearregion(int, int, int, int);
    176 static void tcursor(int);
    177 static void tdeletechar(int);
    178 static void tdeleteline(int);
    179 static void tinsertblank(int);
    180 static void tinsertblankline(int);
    181 static int tlinelen(int);
    182 static void tmoveto(int, int);
    183 static void tmoveato(int, int);
    184 static void tnewline(int);
    185 static void tputtab(int);
    186 static void tputc(Rune);
    187 static void treset(void);
    188 static void tscrollup(int, int);
    189 static void tscrolldown(int, int);
    190 static void tsetattr(const int *, int);
    191 static void tsetchar(Rune, const Glyph *, int, int);
    192 static void tsetdirt(int, int);
    193 static void tsetscroll(int, int);
    194 static void tswapscreen(void);
    195 static void tsetmode(int, int, const int *, int);
    196 static int twrite(const char *, int, int);
    197 static void tfulldirt(void);
    198 static void tcontrolcode(uchar );
    199 static void tdectest(char );
    200 static void tdefutf8(char);
    201 static int32_t tdefcolor(const int *, int *, int);
    202 static void tdeftran(char);
    203 static void tstrsequence(uchar);
    204 
    205 static void drawregion(int, int, int, int);
    206 
    207 static void selnormalize(void);
    208 static void selscroll(int, int);
    209 static void selsnap(int *, int *, int);
    210 
    211 static size_t utf8decode(const char *, Rune *, size_t);
    212 static Rune utf8decodebyte(char, size_t *);
    213 static char utf8encodebyte(Rune, size_t);
    214 static size_t utf8validate(Rune *, size_t);
    215 
    216 static char *base64dec(const char *);
    217 static char base64dec_getc(const char **);
    218 
    219 static ssize_t xwrite(int, const char *, size_t);
    220 
    221 /* Globals */
    222 static Term term;
    223 static Selection sel;
    224 static CSIEscape csiescseq;
    225 static STREscape strescseq;
    226 static int iofd = 1;
    227 static int cmdfd;
    228 static pid_t pid;
    229 
    230 static const uchar utfbyte[UTF_SIZ + 1] = {0x80,    0, 0xC0, 0xE0, 0xF0};
    231 static const uchar utfmask[UTF_SIZ + 1] = {0xC0, 0x80, 0xE0, 0xF0, 0xF8};
    232 static const Rune utfmin[UTF_SIZ + 1] = {       0,    0,  0x80,  0x800,  0x10000};
    233 static const Rune utfmax[UTF_SIZ + 1] = {0x10FFFF, 0x7F, 0x7FF, 0xFFFF, 0x10FFFF};
    234 
    235 ssize_t
    236 xwrite(int fd, const char *s, size_t len)
    237 {
    238 	size_t aux = len;
    239 	ssize_t r;
    240 
    241 	while (len > 0) {
    242 		r = write(fd, s, len);
    243 		if (r < 0)
    244 			return r;
    245 		len -= r;
    246 		s += r;
    247 	}
    248 
    249 	return aux;
    250 }
    251 
    252 void *
    253 xmalloc(size_t len)
    254 {
    255 	void *p;
    256 
    257 	if (!(p = malloc(len)))
    258 		die("malloc: %s\n", strerror(errno));
    259 
    260 	return p;
    261 }
    262 
    263 void *
    264 xrealloc(void *p, size_t len)
    265 {
    266 	if ((p = realloc(p, len)) == NULL)
    267 		die("realloc: %s\n", strerror(errno));
    268 
    269 	return p;
    270 }
    271 
    272 char *
    273 xstrdup(const char *s)
    274 {
    275 	char *p;
    276 
    277 	if ((p = strdup(s)) == NULL)
    278 		die("strdup: %s\n", strerror(errno));
    279 
    280 	return p;
    281 }
    282 
    283 size_t
    284 utf8decode(const char *c, Rune *u, size_t clen)
    285 {
    286 	size_t i, j, len, type;
    287 	Rune udecoded;
    288 
    289 	*u = UTF_INVALID;
    290 	if (!clen)
    291 		return 0;
    292 	udecoded = utf8decodebyte(c[0], &len);
    293 	if (!BETWEEN(len, 1, UTF_SIZ))
    294 		return 1;
    295 	for (i = 1, j = 1; i < clen && j < len; ++i, ++j) {
    296 		udecoded = (udecoded << 6) | utf8decodebyte(c[i], &type);
    297 		if (type != 0)
    298 			return j;
    299 	}
    300 	if (j < len)
    301 		return 0;
    302 	*u = udecoded;
    303 	utf8validate(u, len);
    304 
    305 	return len;
    306 }
    307 
    308 Rune
    309 utf8decodebyte(char c, size_t *i)
    310 {
    311 	for (*i = 0; *i < LEN(utfmask); ++(*i))
    312 		if (((uchar)c & utfmask[*i]) == utfbyte[*i])
    313 			return (uchar)c & ~utfmask[*i];
    314 
    315 	return 0;
    316 }
    317 
    318 size_t
    319 utf8encode(Rune u, char *c)
    320 {
    321 	size_t len, i;
    322 
    323 	len = utf8validate(&u, 0);
    324 	if (len > UTF_SIZ)
    325 		return 0;
    326 
    327 	for (i = len - 1; i != 0; --i) {
    328 		c[i] = utf8encodebyte(u, 0);
    329 		u >>= 6;
    330 	}
    331 	c[0] = utf8encodebyte(u, len);
    332 
    333 	return len;
    334 }
    335 
    336 char
    337 utf8encodebyte(Rune u, size_t i)
    338 {
    339 	return utfbyte[i] | (u & ~utfmask[i]);
    340 }
    341 
    342 size_t
    343 utf8validate(Rune *u, size_t i)
    344 {
    345 	if (!BETWEEN(*u, utfmin[i], utfmax[i]) || BETWEEN(*u, 0xD800, 0xDFFF))
    346 		*u = UTF_INVALID;
    347 	for (i = 1; *u > utfmax[i]; ++i)
    348 		;
    349 
    350 	return i;
    351 }
    352 
    353 char
    354 base64dec_getc(const char **src)
    355 {
    356 	while (**src && !isprint((unsigned char)**src))
    357 		(*src)++;
    358 	return **src ? *((*src)++) : '=';  /* emulate padding if string ends */
    359 }
    360 
    361 char *
    362 base64dec(const char *src)
    363 {
    364 	size_t in_len = strlen(src);
    365 	char *result, *dst;
    366 	static const char base64_digits[256] = {
    367 		[43] = 62, 0, 0, 0, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,
    368 		0, 0, 0, -1, 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12,
    369 		13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 0, 0, 0, 0,
    370 		0, 0, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39,
    371 		40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51
    372 	};
    373 
    374 	if (in_len % 4)
    375 		in_len += 4 - (in_len % 4);
    376 	result = dst = xmalloc(in_len / 4 * 3 + 1);
    377 	while (*src) {
    378 		int a = base64_digits[(unsigned char) base64dec_getc(&src)];
    379 		int b = base64_digits[(unsigned char) base64dec_getc(&src)];
    380 		int c = base64_digits[(unsigned char) base64dec_getc(&src)];
    381 		int d = base64_digits[(unsigned char) base64dec_getc(&src)];
    382 
    383 		/* invalid input. 'a' can be -1, e.g. if src is "\n" (c-str) */
    384 		if (a == -1 || b == -1)
    385 			break;
    386 
    387 		*dst++ = (a << 2) | ((b & 0x30) >> 4);
    388 		if (c == -1)
    389 			break;
    390 		*dst++ = ((b & 0x0f) << 4) | ((c & 0x3c) >> 2);
    391 		if (d == -1)
    392 			break;
    393 		*dst++ = ((c & 0x03) << 6) | d;
    394 	}
    395 	*dst = '\0';
    396 	return result;
    397 }
    398 
    399 void
    400 selinit(void)
    401 {
    402 	sel.mode = SEL_IDLE;
    403 	sel.snap = 0;
    404 	sel.ob.x = -1;
    405 }
    406 
    407 int
    408 tlinelen(int y)
    409 {
    410 	int i = term.col;
    411 
    412 	if (term.line[y][i - 1].mode & ATTR_WRAP)
    413 		return i;
    414 
    415 	while (i > 0 && term.line[y][i - 1].u == ' ')
    416 		--i;
    417 
    418 	return i;
    419 }
    420 
    421 void
    422 selstart(int col, int row, int snap)
    423 {
    424 	selclear();
    425 	sel.mode = SEL_EMPTY;
    426 	sel.type = SEL_REGULAR;
    427 	sel.alt = IS_SET(MODE_ALTSCREEN);
    428 	sel.snap = snap;
    429 	sel.oe.x = sel.ob.x = col;
    430 	sel.oe.y = sel.ob.y = row;
    431 	selnormalize();
    432 
    433 	if (sel.snap != 0)
    434 		sel.mode = SEL_READY;
    435 	tsetdirt(sel.nb.y, sel.ne.y);
    436 }
    437 
    438 void
    439 selextend(int col, int row, int type, int done)
    440 {
    441 	int oldey, oldex, oldsby, oldsey, oldtype;
    442 
    443 	if (sel.mode == SEL_IDLE)
    444 		return;
    445 	if (done && sel.mode == SEL_EMPTY) {
    446 		selclear();
    447 		return;
    448 	}
    449 
    450 	oldey = sel.oe.y;
    451 	oldex = sel.oe.x;
    452 	oldsby = sel.nb.y;
    453 	oldsey = sel.ne.y;
    454 	oldtype = sel.type;
    455 
    456 	sel.oe.x = col;
    457 	sel.oe.y = row;
    458 	selnormalize();
    459 	sel.type = type;
    460 
    461 	if (oldey != sel.oe.y || oldex != sel.oe.x || oldtype != sel.type || sel.mode == SEL_EMPTY)
    462 		tsetdirt(MIN(sel.nb.y, oldsby), MAX(sel.ne.y, oldsey));
    463 
    464 	sel.mode = done ? SEL_IDLE : SEL_READY;
    465 }
    466 
    467 void
    468 selnormalize(void)
    469 {
    470 	int i;
    471 
    472 	if (sel.type == SEL_REGULAR && sel.ob.y != sel.oe.y) {
    473 		sel.nb.x = sel.ob.y < sel.oe.y ? sel.ob.x : sel.oe.x;
    474 		sel.ne.x = sel.ob.y < sel.oe.y ? sel.oe.x : sel.ob.x;
    475 	} else {
    476 		sel.nb.x = MIN(sel.ob.x, sel.oe.x);
    477 		sel.ne.x = MAX(sel.ob.x, sel.oe.x);
    478 	}
    479 	sel.nb.y = MIN(sel.ob.y, sel.oe.y);
    480 	sel.ne.y = MAX(sel.ob.y, sel.oe.y);
    481 
    482 	selsnap(&sel.nb.x, &sel.nb.y, -1);
    483 	selsnap(&sel.ne.x, &sel.ne.y, +1);
    484 
    485 	/* expand selection over line breaks */
    486 	if (sel.type == SEL_RECTANGULAR)
    487 		return;
    488 	i = tlinelen(sel.nb.y);
    489 	if (i < sel.nb.x)
    490 		sel.nb.x = i;
    491 	if (tlinelen(sel.ne.y) <= sel.ne.x)
    492 		sel.ne.x = term.col - 1;
    493 }
    494 
    495 int
    496 selected(int x, int y)
    497 {
    498 	if (sel.mode == SEL_EMPTY || sel.ob.x == -1 ||
    499 			sel.alt != IS_SET(MODE_ALTSCREEN))
    500 		return 0;
    501 
    502 	if (sel.type == SEL_RECTANGULAR)
    503 		return BETWEEN(y, sel.nb.y, sel.ne.y)
    504 		    && BETWEEN(x, sel.nb.x, sel.ne.x);
    505 
    506 	return BETWEEN(y, sel.nb.y, sel.ne.y)
    507 	    && (y != sel.nb.y || x >= sel.nb.x)
    508 	    && (y != sel.ne.y || x <= sel.ne.x);
    509 }
    510 
    511 void
    512 selsnap(int *x, int *y, int direction)
    513 {
    514 	int newx, newy, xt, yt;
    515 	int delim, prevdelim;
    516 	const Glyph *gp, *prevgp;
    517 
    518 	switch (sel.snap) {
    519 	case SNAP_WORD:
    520 		/*
    521 		 * Snap around if the word wraps around at the end or
    522 		 * beginning of a line.
    523 		 */
    524 		prevgp = &term.line[*y][*x];
    525 		prevdelim = ISDELIM(prevgp->u);
    526 		for (;;) {
    527 			newx = *x + direction;
    528 			newy = *y;
    529 			if (!BETWEEN(newx, 0, term.col - 1)) {
    530 				newy += direction;
    531 				newx = (newx + term.col) % term.col;
    532 				if (!BETWEEN(newy, 0, term.row - 1))
    533 					break;
    534 
    535 				if (direction > 0)
    536 					yt = *y, xt = *x;
    537 				else
    538 					yt = newy, xt = newx;
    539 				if (!(term.line[yt][xt].mode & ATTR_WRAP))
    540 					break;
    541 			}
    542 
    543 			if (newx >= tlinelen(newy))
    544 				break;
    545 
    546 			gp = &term.line[newy][newx];
    547 			delim = ISDELIM(gp->u);
    548 			if (!(gp->mode & ATTR_WDUMMY) && (delim != prevdelim
    549 					|| (delim && gp->u != prevgp->u)))
    550 				break;
    551 
    552 			*x = newx;
    553 			*y = newy;
    554 			prevgp = gp;
    555 			prevdelim = delim;
    556 		}
    557 		break;
    558 	case SNAP_LINE:
    559 		/*
    560 		 * Snap around if the the previous line or the current one
    561 		 * has set ATTR_WRAP at its end. Then the whole next or
    562 		 * previous line will be selected.
    563 		 */
    564 		*x = (direction < 0) ? 0 : term.col - 1;
    565 		if (direction < 0) {
    566 			for (; *y > 0; *y += direction) {
    567 				if (!(term.line[*y-1][term.col-1].mode
    568 						& ATTR_WRAP)) {
    569 					break;
    570 				}
    571 			}
    572 		} else if (direction > 0) {
    573 			for (; *y < term.row-1; *y += direction) {
    574 				if (!(term.line[*y][term.col-1].mode
    575 						& ATTR_WRAP)) {
    576 					break;
    577 				}
    578 			}
    579 		}
    580 		break;
    581 	}
    582 }
    583 
    584 char *
    585 getsel(void)
    586 {
    587 	char *str, *ptr;
    588 	int y, bufsize, lastx, linelen;
    589 	const Glyph *gp, *last;
    590 
    591 	if (sel.ob.x == -1)
    592 		return NULL;
    593 
    594 	bufsize = (term.col+1) * (sel.ne.y-sel.nb.y+1) * UTF_SIZ;
    595 	ptr = str = xmalloc(bufsize);
    596 
    597 	/* append every set & selected glyph to the selection */
    598 	for (y = sel.nb.y; y <= sel.ne.y; y++) {
    599 		if ((linelen = tlinelen(y)) == 0) {
    600 			*ptr++ = '\n';
    601 			continue;
    602 		}
    603 
    604 		if (sel.type == SEL_RECTANGULAR) {
    605 			gp = &term.line[y][sel.nb.x];
    606 			lastx = sel.ne.x;
    607 		} else {
    608 			gp = &term.line[y][sel.nb.y == y ? sel.nb.x : 0];
    609 			lastx = (sel.ne.y == y) ? sel.ne.x : term.col-1;
    610 		}
    611 		last = &term.line[y][MIN(lastx, linelen-1)];
    612 		while (last >= gp && last->u == ' ')
    613 			--last;
    614 
    615 		for ( ; gp <= last; ++gp) {
    616 			if (gp->mode & ATTR_WDUMMY)
    617 				continue;
    618 
    619 			ptr += utf8encode(gp->u, ptr);
    620 		}
    621 
    622 		/*
    623 		 * Copy and pasting of line endings is inconsistent
    624 		 * in the inconsistent terminal and GUI world.
    625 		 * The best solution seems like to produce '\n' when
    626 		 * something is copied from st and convert '\n' to
    627 		 * '\r', when something to be pasted is received by
    628 		 * st.
    629 		 * FIXME: Fix the computer world.
    630 		 */
    631 		if ((y < sel.ne.y || lastx >= linelen) &&
    632 		    (!(last->mode & ATTR_WRAP) || sel.type == SEL_RECTANGULAR))
    633 			*ptr++ = '\n';
    634 	}
    635 	*ptr = 0;
    636 	return str;
    637 }
    638 
    639 void
    640 selclear(void)
    641 {
    642 	if (sel.ob.x == -1)
    643 		return;
    644 	sel.mode = SEL_IDLE;
    645 	sel.ob.x = -1;
    646 	tsetdirt(sel.nb.y, sel.ne.y);
    647 }
    648 
    649 void
    650 die(const char *errstr, ...)
    651 {
    652 	va_list ap;
    653 
    654 	va_start(ap, errstr);
    655 	vfprintf(stderr, errstr, ap);
    656 	va_end(ap);
    657 	exit(1);
    658 }
    659 
    660 void
    661 execsh(char *cmd, char **args)
    662 {
    663 	char *sh, *prog, *arg;
    664 	const struct passwd *pw;
    665 
    666 	errno = 0;
    667 	if ((pw = getpwuid(getuid())) == NULL) {
    668 		if (errno)
    669 			die("getpwuid: %s\n", strerror(errno));
    670 		else
    671 			die("who are you?\n");
    672 	}
    673 
    674 	if ((sh = getenv("SHELL")) == NULL)
    675 		sh = (pw->pw_shell[0]) ? pw->pw_shell : cmd;
    676 
    677 	if (args) {
    678 		prog = args[0];
    679 		arg = NULL;
    680 	} else if (scroll) {
    681 		prog = scroll;
    682 		arg = utmp ? utmp : sh;
    683 	} else if (utmp) {
    684 		prog = utmp;
    685 		arg = NULL;
    686 	} else {
    687 		prog = sh;
    688 		arg = NULL;
    689 	}
    690 	DEFAULT(args, ((char *[]) {prog, arg, NULL}));
    691 
    692 	unsetenv("COLUMNS");
    693 	unsetenv("LINES");
    694 	unsetenv("TERMCAP");
    695 	setenv("LOGNAME", pw->pw_name, 1);
    696 	setenv("USER", pw->pw_name, 1);
    697 	setenv("SHELL", sh, 1);
    698 	setenv("HOME", pw->pw_dir, 1);
    699 	setenv("TERM", termname, 1);
    700 
    701 	signal(SIGCHLD, SIG_DFL);
    702 	signal(SIGHUP, SIG_DFL);
    703 	signal(SIGINT, SIG_DFL);
    704 	signal(SIGQUIT, SIG_DFL);
    705 	signal(SIGTERM, SIG_DFL);
    706 	signal(SIGALRM, SIG_DFL);
    707 
    708 	execvp(prog, args);
    709 	_exit(1);
    710 }
    711 
    712 void
    713 sigchld(int a)
    714 {
    715 	int stat;
    716 	pid_t p;
    717 
    718 	if ((p = waitpid(pid, &stat, WNOHANG)) < 0)
    719 		die("waiting for pid %hd failed: %s\n", pid, strerror(errno));
    720 
    721 	if (pid != p)
    722 		return;
    723 
    724 	if (WIFEXITED(stat) && WEXITSTATUS(stat))
    725 		die("child exited with status %d\n", WEXITSTATUS(stat));
    726 	else if (WIFSIGNALED(stat))
    727 		die("child terminated due to signal %d\n", WTERMSIG(stat));
    728 	_exit(0);
    729 }
    730 
    731 void
    732 stty(char **args)
    733 {
    734 	char cmd[_POSIX_ARG_MAX], **p, *q, *s;
    735 	size_t n, siz;
    736 
    737 	if ((n = strlen(stty_args)) > sizeof(cmd)-1)
    738 		die("incorrect stty parameters\n");
    739 	memcpy(cmd, stty_args, n);
    740 	q = cmd + n;
    741 	siz = sizeof(cmd) - n;
    742 	for (p = args; p && (s = *p); ++p) {
    743 		if ((n = strlen(s)) > siz-1)
    744 			die("stty parameter length too long\n");
    745 		*q++ = ' ';
    746 		memcpy(q, s, n);
    747 		q += n;
    748 		siz -= n + 1;
    749 	}
    750 	*q = '\0';
    751 	if (system(cmd) != 0)
    752 		perror("Couldn't call stty");
    753 }
    754 
    755 int
    756 ttynew(const char *line, char *cmd, const char *out, char **args)
    757 {
    758 	int m, s;
    759 
    760 	if (out) {
    761 		term.mode |= MODE_PRINT;
    762 		iofd = (!strcmp(out, "-")) ?
    763 			  1 : open(out, O_WRONLY | O_CREAT, 0666);
    764 		if (iofd < 0) {
    765 			fprintf(stderr, "Error opening %s:%s\n",
    766 				out, strerror(errno));
    767 		}
    768 	}
    769 
    770 	if (line) {
    771 		if ((cmdfd = open(line, O_RDWR)) < 0)
    772 			die("open line '%s' failed: %s\n",
    773 			    line, strerror(errno));
    774 		dup2(cmdfd, 0);
    775 		stty(args);
    776 		return cmdfd;
    777 	}
    778 
    779 	/* seems to work fine on linux, openbsd and freebsd */
    780 	if (openpty(&m, &s, NULL, NULL, NULL) < 0)
    781 		die("openpty failed: %s\n", strerror(errno));
    782 
    783 	switch (pid = fork()) {
    784 	case -1:
    785 		die("fork failed: %s\n", strerror(errno));
    786 		break;
    787 	case 0:
    788 		close(iofd);
    789 		close(m);
    790 		setsid(); /* create a new process group */
    791 		dup2(s, 0);
    792 		dup2(s, 1);
    793 		dup2(s, 2);
    794 		if (ioctl(s, TIOCSCTTY, NULL) < 0)
    795 			die("ioctl TIOCSCTTY failed: %s\n", strerror(errno));
    796 		if (s > 2)
    797 			close(s);
    798 #ifdef __OpenBSD__
    799 		if (pledge("stdio getpw proc exec", NULL) == -1)
    800 			die("pledge\n");
    801 #endif
    802 		execsh(cmd, args);
    803 		break;
    804 	default:
    805 #ifdef __OpenBSD__
    806 		if (pledge("stdio rpath tty proc", NULL) == -1)
    807 			die("pledge\n");
    808 #endif
    809 		close(s);
    810 		cmdfd = m;
    811 		signal(SIGCHLD, sigchld);
    812 		break;
    813 	}
    814 	return cmdfd;
    815 }
    816 
    817 size_t
    818 ttyread(void)
    819 {
    820 	static char buf[BUFSIZ];
    821 	static int buflen = 0;
    822 	int ret, written;
    823 
    824 	/* append read bytes to unprocessed bytes */
    825 	ret = read(cmdfd, buf+buflen, LEN(buf)-buflen);
    826 
    827 	switch (ret) {
    828 	case 0:
    829 		exit(0);
    830 	case -1:
    831 		die("couldn't read from shell: %s\n", strerror(errno));
    832 	default:
    833 		buflen += ret;
    834 		written = twrite(buf, buflen, 0);
    835 		buflen -= written;
    836 		/* keep any incomplete UTF-8 byte sequence for the next call */
    837 		if (buflen > 0)
    838 			memmove(buf, buf + written, buflen);
    839 		return ret;
    840 	}
    841 }
    842 
    843 void
    844 ttywrite(const char *s, size_t n, int may_echo)
    845 {
    846 	const char *next;
    847 
    848 	if (may_echo && IS_SET(MODE_ECHO))
    849 		twrite(s, n, 1);
    850 
    851 	if (!IS_SET(MODE_CRLF)) {
    852 		ttywriteraw(s, n);
    853 		return;
    854 	}
    855 
    856 	/* This is similar to how the kernel handles ONLCR for ttys */
    857 	while (n > 0) {
    858 		if (*s == '\r') {
    859 			next = s + 1;
    860 			ttywriteraw("\r\n", 2);
    861 		} else {
    862 			next = memchr(s, '\r', n);
    863 			DEFAULT(next, s + n);
    864 			ttywriteraw(s, next - s);
    865 		}
    866 		n -= next - s;
    867 		s = next;
    868 	}
    869 }
    870 
    871 void
    872 ttywriteraw(const char *s, size_t n)
    873 {
    874 	fd_set wfd, rfd;
    875 	ssize_t r;
    876 	size_t lim = 256;
    877 
    878 	/*
    879 	 * Remember that we are using a pty, which might be a modem line.
    880 	 * Writing too much will clog the line. That's why we are doing this
    881 	 * dance.
    882 	 * FIXME: Migrate the world to Plan 9.
    883 	 */
    884 	while (n > 0) {
    885 		FD_ZERO(&wfd);
    886 		FD_ZERO(&rfd);
    887 		FD_SET(cmdfd, &wfd);
    888 		FD_SET(cmdfd, &rfd);
    889 
    890 		/* Check if we can write. */
    891 		if (pselect(cmdfd+1, &rfd, &wfd, NULL, NULL, NULL) < 0) {
    892 			if (errno == EINTR)
    893 				continue;
    894 			die("select failed: %s\n", strerror(errno));
    895 		}
    896 		if (FD_ISSET(cmdfd, &wfd)) {
    897 			/*
    898 			 * Only write the bytes written by ttywrite() or the
    899 			 * default of 256. This seems to be a reasonable value
    900 			 * for a serial line. Bigger values might clog the I/O.
    901 			 */
    902 			if ((r = write(cmdfd, s, (n < lim)? n : lim)) < 0)
    903 				goto write_error;
    904 			if (r < n) {
    905 				/*
    906 				 * We weren't able to write out everything.
    907 				 * This means the buffer is getting full
    908 				 * again. Empty it.
    909 				 */
    910 				if (n < lim)
    911 					lim = ttyread();
    912 				n -= r;
    913 				s += r;
    914 			} else {
    915 				/* All bytes have been written. */
    916 				break;
    917 			}
    918 		}
    919 		if (FD_ISSET(cmdfd, &rfd))
    920 			lim = ttyread();
    921 	}
    922 	return;
    923 
    924 write_error:
    925 	die("write error on tty: %s\n", strerror(errno));
    926 }
    927 
    928 void
    929 ttyresize(int tw, int th)
    930 {
    931 	struct winsize w;
    932 
    933 	w.ws_row = term.row;
    934 	w.ws_col = term.col;
    935 	w.ws_xpixel = tw;
    936 	w.ws_ypixel = th;
    937 	if (ioctl(cmdfd, TIOCSWINSZ, &w) < 0)
    938 		fprintf(stderr, "Couldn't set window size: %s\n", strerror(errno));
    939 }
    940 
    941 void
    942 ttyhangup(void)
    943 {
    944 	/* Send SIGHUP to shell */
    945 	kill(pid, SIGHUP);
    946 }
    947 
    948 int
    949 tattrset(int attr)
    950 {
    951 	int i, j;
    952 
    953 	for (i = 0; i < term.row-1; i++) {
    954 		for (j = 0; j < term.col-1; j++) {
    955 			if (term.line[i][j].mode & attr)
    956 				return 1;
    957 		}
    958 	}
    959 
    960 	return 0;
    961 }
    962 
    963 void
    964 tsetdirt(int top, int bot)
    965 {
    966 	int i;
    967 
    968 	LIMIT(top, 0, term.row-1);
    969 	LIMIT(bot, 0, term.row-1);
    970 
    971 	for (i = top; i <= bot; i++)
    972 		term.dirty[i] = 1;
    973 }
    974 
    975 void
    976 tsetdirtattr(int attr)
    977 {
    978 	int i, j;
    979 
    980 	for (i = 0; i < term.row-1; i++) {
    981 		for (j = 0; j < term.col-1; j++) {
    982 			if (term.line[i][j].mode & attr) {
    983 				tsetdirt(i, i);
    984 				break;
    985 			}
    986 		}
    987 	}
    988 }
    989 
    990 void
    991 tfulldirt(void)
    992 {
    993 	tsetdirt(0, term.row-1);
    994 }
    995 
    996 void
    997 tcursor(int mode)
    998 {
    999 	static TCursor c[2];
   1000 	int alt = IS_SET(MODE_ALTSCREEN);
   1001 
   1002 	if (mode == CURSOR_SAVE) {
   1003 		c[alt] = term.c;
   1004 	} else if (mode == CURSOR_LOAD) {
   1005 		term.c = c[alt];
   1006 		tmoveto(c[alt].x, c[alt].y);
   1007 	}
   1008 }
   1009 
   1010 void
   1011 treset(void)
   1012 {
   1013 	uint i;
   1014 
   1015 	term.c = (TCursor){{
   1016 		.mode = ATTR_NULL,
   1017 		.fg = defaultfg,
   1018 		.bg = defaultbg
   1019 	}, .x = 0, .y = 0, .state = CURSOR_DEFAULT};
   1020 
   1021 	memset(term.tabs, 0, term.col * sizeof(*term.tabs));
   1022 	for (i = tabspaces; i < term.col; i += tabspaces)
   1023 		term.tabs[i] = 1;
   1024 	term.top = 0;
   1025 	term.bot = term.row - 1;
   1026 	term.mode = MODE_WRAP|MODE_UTF8;
   1027 	memset(term.trantbl, CS_USA, sizeof(term.trantbl));
   1028 	term.charset = 0;
   1029 
   1030 	for (i = 0; i < 2; i++) {
   1031 		tmoveto(0, 0);
   1032 		tcursor(CURSOR_SAVE);
   1033 		tclearregion(0, 0, term.col-1, term.row-1);
   1034 		tswapscreen();
   1035 	}
   1036 }
   1037 
   1038 void
   1039 tnew(int col, int row)
   1040 {
   1041 	term = (Term){ .c = { .attr = { .fg = defaultfg, .bg = defaultbg } } };
   1042 	tresize(col, row);
   1043 	treset();
   1044 }
   1045 
   1046 void
   1047 tswapscreen(void)
   1048 {
   1049 	Line *tmp = term.line;
   1050 
   1051 	term.line = term.alt;
   1052 	term.alt = tmp;
   1053 	term.mode ^= MODE_ALTSCREEN;
   1054 	tfulldirt();
   1055 }
   1056 
   1057 void
   1058 tscrolldown(int orig, int n)
   1059 {
   1060 	int i;
   1061 	Line temp;
   1062 
   1063 	LIMIT(n, 0, term.bot-orig+1);
   1064 
   1065 	tsetdirt(orig, term.bot-n);
   1066 	tclearregion(0, term.bot-n+1, term.col-1, term.bot);
   1067 
   1068 	for (i = term.bot; i >= orig+n; i--) {
   1069 		temp = term.line[i];
   1070 		term.line[i] = term.line[i-n];
   1071 		term.line[i-n] = temp;
   1072 	}
   1073 
   1074 	selscroll(orig, n);
   1075 }
   1076 
   1077 void
   1078 tscrollup(int orig, int n)
   1079 {
   1080 	int i;
   1081 	Line temp;
   1082 
   1083 	LIMIT(n, 0, term.bot-orig+1);
   1084 
   1085 	tclearregion(0, orig, term.col-1, orig+n-1);
   1086 	tsetdirt(orig+n, term.bot);
   1087 
   1088 	for (i = orig; i <= term.bot-n; i++) {
   1089 		temp = term.line[i];
   1090 		term.line[i] = term.line[i+n];
   1091 		term.line[i+n] = temp;
   1092 	}
   1093 
   1094 	selscroll(orig, -n);
   1095 }
   1096 
   1097 void
   1098 selscroll(int orig, int n)
   1099 {
   1100 	if (sel.ob.x == -1 || sel.alt != IS_SET(MODE_ALTSCREEN))
   1101 		return;
   1102 
   1103 	if (BETWEEN(sel.nb.y, orig, term.bot) != BETWEEN(sel.ne.y, orig, term.bot)) {
   1104 		selclear();
   1105 	} else if (BETWEEN(sel.nb.y, orig, term.bot)) {
   1106 		sel.ob.y += n;
   1107 		sel.oe.y += n;
   1108 		if (sel.ob.y < term.top || sel.ob.y > term.bot ||
   1109 		    sel.oe.y < term.top || sel.oe.y > term.bot) {
   1110 			selclear();
   1111 		} else {
   1112 			selnormalize();
   1113 		}
   1114 	}
   1115 }
   1116 
   1117 void
   1118 tnewline(int first_col)
   1119 {
   1120 	int y = term.c.y;
   1121 
   1122 	if (y == term.bot) {
   1123 		tscrollup(term.top, 1);
   1124 	} else {
   1125 		y++;
   1126 	}
   1127 	tmoveto(first_col ? 0 : term.c.x, y);
   1128 }
   1129 
   1130 void
   1131 csiparse(void)
   1132 {
   1133 	char *p = csiescseq.buf, *np;
   1134 	long int v;
   1135 	int sep = ';'; /* colon or semi-colon, but not both */
   1136 
   1137 	csiescseq.narg = 0;
   1138 	if (*p == '?') {
   1139 		csiescseq.priv = 1;
   1140 		p++;
   1141 	}
   1142 
   1143 	csiescseq.buf[csiescseq.len] = '\0';
   1144 	while (p < csiescseq.buf+csiescseq.len) {
   1145 		np = NULL;
   1146 		v = strtol(p, &np, 10);
   1147 		if (np == p)
   1148 			v = 0;
   1149 		if (v == LONG_MAX || v == LONG_MIN)
   1150 			v = -1;
   1151 		csiescseq.arg[csiescseq.narg++] = v;
   1152 		p = np;
   1153 		if (sep == ';' && *p == ':')
   1154 			sep = ':'; /* allow override to colon once */
   1155 		if (*p != sep || csiescseq.narg == ESC_ARG_SIZ)
   1156 			break;
   1157 		p++;
   1158 	}
   1159 	csiescseq.mode[0] = *p++;
   1160 	csiescseq.mode[1] = (p < csiescseq.buf+csiescseq.len) ? *p : '\0';
   1161 }
   1162 
   1163 /* for absolute user moves, when decom is set */
   1164 void
   1165 tmoveato(int x, int y)
   1166 {
   1167 	tmoveto(x, y + ((term.c.state & CURSOR_ORIGIN) ? term.top: 0));
   1168 }
   1169 
   1170 void
   1171 tmoveto(int x, int y)
   1172 {
   1173 	int miny, maxy;
   1174 
   1175 	if (term.c.state & CURSOR_ORIGIN) {
   1176 		miny = term.top;
   1177 		maxy = term.bot;
   1178 	} else {
   1179 		miny = 0;
   1180 		maxy = term.row - 1;
   1181 	}
   1182 	term.c.state &= ~CURSOR_WRAPNEXT;
   1183 	term.c.x = LIMIT(x, 0, term.col-1);
   1184 	term.c.y = LIMIT(y, miny, maxy);
   1185 }
   1186 
   1187 void
   1188 tsetchar(Rune u, const Glyph *attr, int x, int y)
   1189 {
   1190 	static const char *vt100_0[62] = { /* 0x41 - 0x7e */
   1191 		"↑", "↓", "→", "←", "█", "▚", "☃", /* A - G */
   1192 		0, 0, 0, 0, 0, 0, 0, 0, /* H - O */
   1193 		0, 0, 0, 0, 0, 0, 0, 0, /* P - W */
   1194 		0, 0, 0, 0, 0, 0, 0, " ", /* X - _ */
   1195 		"◆", "▒", "␉", "␌", "␍", "␊", "°", "±", /* ` - g */
   1196 		"␤", "␋", "┘", "┐", "┌", "└", "┼", "⎺", /* h - o */
   1197 		"⎻", "─", "⎼", "⎽", "├", "┤", "┴", "┬", /* p - w */
   1198 		"│", "≤", "≥", "π", "≠", "£", "·", /* x - ~ */
   1199 	};
   1200 
   1201 	/*
   1202 	 * The table is proudly stolen from rxvt.
   1203 	 */
   1204 	if (term.trantbl[term.charset] == CS_GRAPHIC0 &&
   1205 	   BETWEEN(u, 0x41, 0x7e) && vt100_0[u - 0x41])
   1206 		utf8decode(vt100_0[u - 0x41], &u, UTF_SIZ);
   1207 
   1208 	if (term.line[y][x].mode & ATTR_WIDE) {
   1209 		if (x+1 < term.col) {
   1210 			term.line[y][x+1].u = ' ';
   1211 			term.line[y][x+1].mode &= ~ATTR_WDUMMY;
   1212 		}
   1213 	} else if (term.line[y][x].mode & ATTR_WDUMMY) {
   1214 		term.line[y][x-1].u = ' ';
   1215 		term.line[y][x-1].mode &= ~ATTR_WIDE;
   1216 	}
   1217 
   1218 	term.dirty[y] = 1;
   1219 	term.line[y][x] = *attr;
   1220 	term.line[y][x].u = u;
   1221 
   1222 	if (isboxdraw(u))
   1223 		term.line[y][x].mode |= ATTR_BOXDRAW;
   1224 }
   1225 
   1226 void
   1227 tclearregion(int x1, int y1, int x2, int y2)
   1228 {
   1229 	int x, y, temp;
   1230 	Glyph *gp;
   1231 
   1232 	if (x1 > x2)
   1233 		temp = x1, x1 = x2, x2 = temp;
   1234 	if (y1 > y2)
   1235 		temp = y1, y1 = y2, y2 = temp;
   1236 
   1237 	LIMIT(x1, 0, term.col-1);
   1238 	LIMIT(x2, 0, term.col-1);
   1239 	LIMIT(y1, 0, term.row-1);
   1240 	LIMIT(y2, 0, term.row-1);
   1241 
   1242 	for (y = y1; y <= y2; y++) {
   1243 		term.dirty[y] = 1;
   1244 		for (x = x1; x <= x2; x++) {
   1245 			gp = &term.line[y][x];
   1246 			if (selected(x, y))
   1247 				selclear();
   1248 			gp->fg = term.c.attr.fg;
   1249 			gp->bg = term.c.attr.bg;
   1250 			gp->mode = 0;
   1251 			gp->u = ' ';
   1252 		}
   1253 	}
   1254 }
   1255 
   1256 void
   1257 tdeletechar(int n)
   1258 {
   1259 	int dst, src, size;
   1260 	Glyph *line;
   1261 
   1262 	LIMIT(n, 0, term.col - term.c.x);
   1263 
   1264 	dst = term.c.x;
   1265 	src = term.c.x + n;
   1266 	size = term.col - src;
   1267 	line = term.line[term.c.y];
   1268 
   1269 	memmove(&line[dst], &line[src], size * sizeof(Glyph));
   1270 	tclearregion(term.col-n, term.c.y, term.col-1, term.c.y);
   1271 }
   1272 
   1273 void
   1274 tinsertblank(int n)
   1275 {
   1276 	int dst, src, size;
   1277 	Glyph *line;
   1278 
   1279 	LIMIT(n, 0, term.col - term.c.x);
   1280 
   1281 	dst = term.c.x + n;
   1282 	src = term.c.x;
   1283 	size = term.col - dst;
   1284 	line = term.line[term.c.y];
   1285 
   1286 	memmove(&line[dst], &line[src], size * sizeof(Glyph));
   1287 	tclearregion(src, term.c.y, dst - 1, term.c.y);
   1288 }
   1289 
   1290 void
   1291 tinsertblankline(int n)
   1292 {
   1293 	if (BETWEEN(term.c.y, term.top, term.bot))
   1294 		tscrolldown(term.c.y, n);
   1295 }
   1296 
   1297 void
   1298 tdeleteline(int n)
   1299 {
   1300 	if (BETWEEN(term.c.y, term.top, term.bot))
   1301 		tscrollup(term.c.y, n);
   1302 }
   1303 
   1304 int32_t
   1305 tdefcolor(const int *attr, int *npar, int l)
   1306 {
   1307 	int32_t idx = -1;
   1308 	uint r, g, b;
   1309 
   1310 	switch (attr[*npar + 1]) {
   1311 	case 2: /* direct color in RGB space */
   1312 		if (*npar + 4 >= l) {
   1313 			fprintf(stderr,
   1314 				"erresc(38): Incorrect number of parameters (%d)\n",
   1315 				*npar);
   1316 			break;
   1317 		}
   1318 		r = attr[*npar + 2];
   1319 		g = attr[*npar + 3];
   1320 		b = attr[*npar + 4];
   1321 		*npar += 4;
   1322 		if (!BETWEEN(r, 0, 255) || !BETWEEN(g, 0, 255) || !BETWEEN(b, 0, 255))
   1323 			fprintf(stderr, "erresc: bad rgb color (%u,%u,%u)\n",
   1324 				r, g, b);
   1325 		else
   1326 			idx = TRUECOLOR(r, g, b);
   1327 		break;
   1328 	case 5: /* indexed color */
   1329 		if (*npar + 2 >= l) {
   1330 			fprintf(stderr,
   1331 				"erresc(38): Incorrect number of parameters (%d)\n",
   1332 				*npar);
   1333 			break;
   1334 		}
   1335 		*npar += 2;
   1336 		if (!BETWEEN(attr[*npar], 0, 255))
   1337 			fprintf(stderr, "erresc: bad fgcolor %d\n", attr[*npar]);
   1338 		else
   1339 			idx = attr[*npar];
   1340 		break;
   1341 	case 0: /* implemented defined (only foreground) */
   1342 	case 1: /* transparent */
   1343 	case 3: /* direct color in CMY space */
   1344 	case 4: /* direct color in CMYK space */
   1345 	default:
   1346 		fprintf(stderr,
   1347 		        "erresc(38): gfx attr %d unknown\n", attr[*npar]);
   1348 		break;
   1349 	}
   1350 
   1351 	return idx;
   1352 }
   1353 
   1354 void
   1355 tsetattr(const int *attr, int l)
   1356 {
   1357 	int i;
   1358 	int32_t idx;
   1359 
   1360 	for (i = 0; i < l; i++) {
   1361 		switch (attr[i]) {
   1362 		case 0:
   1363 			term.c.attr.mode &= ~(
   1364 				ATTR_BOLD       |
   1365 				ATTR_FAINT      |
   1366 				ATTR_ITALIC     |
   1367 				ATTR_UNDERLINE  |
   1368 				ATTR_BLINK      |
   1369 				ATTR_REVERSE    |
   1370 				ATTR_INVISIBLE  |
   1371 				ATTR_STRUCK     );
   1372 			term.c.attr.fg = defaultfg;
   1373 			term.c.attr.bg = defaultbg;
   1374 			break;
   1375 		case 1:
   1376 			term.c.attr.mode |= ATTR_BOLD;
   1377 			break;
   1378 		case 2:
   1379 			term.c.attr.mode |= ATTR_FAINT;
   1380 			break;
   1381 		case 3:
   1382 			term.c.attr.mode |= ATTR_ITALIC;
   1383 			break;
   1384 		case 4:
   1385 			term.c.attr.mode |= ATTR_UNDERLINE;
   1386 			break;
   1387 		case 5: /* slow blink */
   1388 			/* FALLTHROUGH */
   1389 		case 6: /* rapid blink */
   1390 			term.c.attr.mode |= ATTR_BLINK;
   1391 			break;
   1392 		case 7:
   1393 			term.c.attr.mode |= ATTR_REVERSE;
   1394 			break;
   1395 		case 8:
   1396 			term.c.attr.mode |= ATTR_INVISIBLE;
   1397 			break;
   1398 		case 9:
   1399 			term.c.attr.mode |= ATTR_STRUCK;
   1400 			break;
   1401 		case 22:
   1402 			term.c.attr.mode &= ~(ATTR_BOLD | ATTR_FAINT);
   1403 			break;
   1404 		case 23:
   1405 			term.c.attr.mode &= ~ATTR_ITALIC;
   1406 			break;
   1407 		case 24:
   1408 			term.c.attr.mode &= ~ATTR_UNDERLINE;
   1409 			break;
   1410 		case 25:
   1411 			term.c.attr.mode &= ~ATTR_BLINK;
   1412 			break;
   1413 		case 27:
   1414 			term.c.attr.mode &= ~ATTR_REVERSE;
   1415 			break;
   1416 		case 28:
   1417 			term.c.attr.mode &= ~ATTR_INVISIBLE;
   1418 			break;
   1419 		case 29:
   1420 			term.c.attr.mode &= ~ATTR_STRUCK;
   1421 			break;
   1422 		case 38:
   1423 			if ((idx = tdefcolor(attr, &i, l)) >= 0)
   1424 				term.c.attr.fg = idx;
   1425 			break;
   1426 		case 39:
   1427 			term.c.attr.fg = defaultfg;
   1428 			break;
   1429 		case 48:
   1430 			if ((idx = tdefcolor(attr, &i, l)) >= 0)
   1431 				term.c.attr.bg = idx;
   1432 			break;
   1433 		case 49:
   1434 			term.c.attr.bg = defaultbg;
   1435 			break;
   1436 		default:
   1437 			if (BETWEEN(attr[i], 30, 37)) {
   1438 				term.c.attr.fg = attr[i] - 30;
   1439 			} else if (BETWEEN(attr[i], 40, 47)) {
   1440 				term.c.attr.bg = attr[i] - 40;
   1441 			} else if (BETWEEN(attr[i], 90, 97)) {
   1442 				term.c.attr.fg = attr[i] - 90 + 8;
   1443 			} else if (BETWEEN(attr[i], 100, 107)) {
   1444 				term.c.attr.bg = attr[i] - 100 + 8;
   1445 			} else {
   1446 				fprintf(stderr,
   1447 					"erresc(default): gfx attr %d unknown\n",
   1448 					attr[i]);
   1449 				csidump();
   1450 			}
   1451 			break;
   1452 		}
   1453 	}
   1454 }
   1455 
   1456 void
   1457 tsetscroll(int t, int b)
   1458 {
   1459 	int temp;
   1460 
   1461 	LIMIT(t, 0, term.row-1);
   1462 	LIMIT(b, 0, term.row-1);
   1463 	if (t > b) {
   1464 		temp = t;
   1465 		t = b;
   1466 		b = temp;
   1467 	}
   1468 	term.top = t;
   1469 	term.bot = b;
   1470 }
   1471 
   1472 void
   1473 tsetmode(int priv, int set, const int *args, int narg)
   1474 {
   1475 	int alt; const int *lim;
   1476 
   1477 	for (lim = args + narg; args < lim; ++args) {
   1478 		if (priv) {
   1479 			switch (*args) {
   1480 			case 1: /* DECCKM -- Cursor key */
   1481 				xsetmode(set, MODE_APPCURSOR);
   1482 				break;
   1483 			case 5: /* DECSCNM -- Reverse video */
   1484 				xsetmode(set, MODE_REVERSE);
   1485 				break;
   1486 			case 6: /* DECOM -- Origin */
   1487 				MODBIT(term.c.state, set, CURSOR_ORIGIN);
   1488 				tmoveato(0, 0);
   1489 				break;
   1490 			case 7: /* DECAWM -- Auto wrap */
   1491 				MODBIT(term.mode, set, MODE_WRAP);
   1492 				break;
   1493 			case 0:  /* Error (IGNORED) */
   1494 			case 2:  /* DECANM -- ANSI/VT52 (IGNORED) */
   1495 			case 3:  /* DECCOLM -- Column  (IGNORED) */
   1496 			case 4:  /* DECSCLM -- Scroll (IGNORED) */
   1497 			case 8:  /* DECARM -- Auto repeat (IGNORED) */
   1498 			case 18: /* DECPFF -- Printer feed (IGNORED) */
   1499 			case 19: /* DECPEX -- Printer extent (IGNORED) */
   1500 			case 42: /* DECNRCM -- National characters (IGNORED) */
   1501 			case 12: /* att610 -- Start blinking cursor (IGNORED) */
   1502 				break;
   1503 			case 25: /* DECTCEM -- Text Cursor Enable Mode */
   1504 				xsetmode(!set, MODE_HIDE);
   1505 				break;
   1506 			case 9:    /* X10 mouse compatibility mode */
   1507 				xsetpointermotion(0);
   1508 				xsetmode(0, MODE_MOUSE);
   1509 				xsetmode(set, MODE_MOUSEX10);
   1510 				break;
   1511 			case 1000: /* 1000: report button press */
   1512 				xsetpointermotion(0);
   1513 				xsetmode(0, MODE_MOUSE);
   1514 				xsetmode(set, MODE_MOUSEBTN);
   1515 				break;
   1516 			case 1002: /* 1002: report motion on button press */
   1517 				xsetpointermotion(0);
   1518 				xsetmode(0, MODE_MOUSE);
   1519 				xsetmode(set, MODE_MOUSEMOTION);
   1520 				break;
   1521 			case 1003: /* 1003: enable all mouse motions */
   1522 				xsetpointermotion(set);
   1523 				xsetmode(0, MODE_MOUSE);
   1524 				xsetmode(set, MODE_MOUSEMANY);
   1525 				break;
   1526 			case 1004: /* 1004: send focus events to tty */
   1527 				xsetmode(set, MODE_FOCUS);
   1528 				break;
   1529 			case 1006: /* 1006: extended reporting mode */
   1530 				xsetmode(set, MODE_MOUSESGR);
   1531 				break;
   1532 			case 1034:
   1533 				xsetmode(set, MODE_8BIT);
   1534 				break;
   1535 			case 1049: /* swap screen & set/restore cursor as xterm */
   1536 				if (!allowaltscreen)
   1537 					break;
   1538 				tcursor((set) ? CURSOR_SAVE : CURSOR_LOAD);
   1539 				/* FALLTHROUGH */
   1540 			case 47: /* swap screen */
   1541 			case 1047:
   1542 				if (!allowaltscreen)
   1543 					break;
   1544 				alt = IS_SET(MODE_ALTSCREEN);
   1545 				if (alt) {
   1546 					tclearregion(0, 0, term.col-1,
   1547 							term.row-1);
   1548 				}
   1549 				if (set ^ alt) /* set is always 1 or 0 */
   1550 					tswapscreen();
   1551 				if (*args != 1049)
   1552 					break;
   1553 				/* FALLTHROUGH */
   1554 			case 1048:
   1555 				tcursor((set) ? CURSOR_SAVE : CURSOR_LOAD);
   1556 				break;
   1557 			case 2004: /* 2004: bracketed paste mode */
   1558 				xsetmode(set, MODE_BRCKTPASTE);
   1559 				break;
   1560 			/* Not implemented mouse modes. See comments there. */
   1561 			case 1001: /* mouse highlight mode; can hang the
   1562 				      terminal by design when implemented. */
   1563 			case 1005: /* UTF-8 mouse mode; will confuse
   1564 				      applications not supporting UTF-8
   1565 				      and luit. */
   1566 			case 1015: /* urxvt mangled mouse mode; incompatible
   1567 				      and can be mistaken for other control
   1568 				      codes. */
   1569 				break;
   1570 			default:
   1571 				fprintf(stderr,
   1572 					"erresc: unknown private set/reset mode %d\n",
   1573 					*args);
   1574 				break;
   1575 			}
   1576 		} else {
   1577 			switch (*args) {
   1578 			case 0:  /* Error (IGNORED) */
   1579 				break;
   1580 			case 2:
   1581 				xsetmode(set, MODE_KBDLOCK);
   1582 				break;
   1583 			case 4:  /* IRM -- Insertion-replacement */
   1584 				MODBIT(term.mode, set, MODE_INSERT);
   1585 				break;
   1586 			case 12: /* SRM -- Send/Receive */
   1587 				MODBIT(term.mode, !set, MODE_ECHO);
   1588 				break;
   1589 			case 20: /* LNM -- Linefeed/new line */
   1590 				MODBIT(term.mode, set, MODE_CRLF);
   1591 				break;
   1592 			default:
   1593 				fprintf(stderr,
   1594 					"erresc: unknown set/reset mode %d\n",
   1595 					*args);
   1596 				break;
   1597 			}
   1598 		}
   1599 	}
   1600 }
   1601 
   1602 void
   1603 csihandle(void)
   1604 {
   1605 	char buf[40];
   1606 	int len;
   1607 
   1608 	switch (csiescseq.mode[0]) {
   1609 	default:
   1610 	unknown:
   1611 		fprintf(stderr, "erresc: unknown csi ");
   1612 		csidump();
   1613 		/* die(""); */
   1614 		break;
   1615 	case '@': /* ICH -- Insert <n> blank char */
   1616 		DEFAULT(csiescseq.arg[0], 1);
   1617 		tinsertblank(csiescseq.arg[0]);
   1618 		break;
   1619 	case 'A': /* CUU -- Cursor <n> Up */
   1620 		DEFAULT(csiescseq.arg[0], 1);
   1621 		tmoveto(term.c.x, term.c.y-csiescseq.arg[0]);
   1622 		break;
   1623 	case 'B': /* CUD -- Cursor <n> Down */
   1624 	case 'e': /* VPR --Cursor <n> Down */
   1625 		DEFAULT(csiescseq.arg[0], 1);
   1626 		tmoveto(term.c.x, term.c.y+csiescseq.arg[0]);
   1627 		break;
   1628 	case 'i': /* MC -- Media Copy */
   1629 		switch (csiescseq.arg[0]) {
   1630 		case 0:
   1631 			tdump();
   1632 			break;
   1633 		case 1:
   1634 			tdumpline(term.c.y);
   1635 			break;
   1636 		case 2:
   1637 			tdumpsel();
   1638 			break;
   1639 		case 4:
   1640 			term.mode &= ~MODE_PRINT;
   1641 			break;
   1642 		case 5:
   1643 			term.mode |= MODE_PRINT;
   1644 			break;
   1645 		}
   1646 		break;
   1647 	case 'c': /* DA -- Device Attributes */
   1648 		if (csiescseq.arg[0] == 0)
   1649 			ttywrite(vtiden, strlen(vtiden), 0);
   1650 		break;
   1651 	case 'b': /* REP -- if last char is printable print it <n> more times */
   1652 		LIMIT(csiescseq.arg[0], 1, 65535);
   1653 		if (term.lastc)
   1654 			while (csiescseq.arg[0]-- > 0)
   1655 				tputc(term.lastc);
   1656 		break;
   1657 	case 'C': /* CUF -- Cursor <n> Forward */
   1658 	case 'a': /* HPR -- Cursor <n> Forward */
   1659 		DEFAULT(csiescseq.arg[0], 1);
   1660 		tmoveto(term.c.x+csiescseq.arg[0], term.c.y);
   1661 		break;
   1662 	case 'D': /* CUB -- Cursor <n> Backward */
   1663 		DEFAULT(csiescseq.arg[0], 1);
   1664 		tmoveto(term.c.x-csiescseq.arg[0], term.c.y);
   1665 		break;
   1666 	case 'E': /* CNL -- Cursor <n> Down and first col */
   1667 		DEFAULT(csiescseq.arg[0], 1);
   1668 		tmoveto(0, term.c.y+csiescseq.arg[0]);
   1669 		break;
   1670 	case 'F': /* CPL -- Cursor <n> Up and first col */
   1671 		DEFAULT(csiescseq.arg[0], 1);
   1672 		tmoveto(0, term.c.y-csiescseq.arg[0]);
   1673 		break;
   1674 	case 'g': /* TBC -- Tabulation clear */
   1675 		switch (csiescseq.arg[0]) {
   1676 		case 0: /* clear current tab stop */
   1677 			term.tabs[term.c.x] = 0;
   1678 			break;
   1679 		case 3: /* clear all the tabs */
   1680 			memset(term.tabs, 0, term.col * sizeof(*term.tabs));
   1681 			break;
   1682 		default:
   1683 			goto unknown;
   1684 		}
   1685 		break;
   1686 	case 'G': /* CHA -- Move to <col> */
   1687 	case '`': /* HPA */
   1688 		DEFAULT(csiescseq.arg[0], 1);
   1689 		tmoveto(csiescseq.arg[0]-1, term.c.y);
   1690 		break;
   1691 	case 'H': /* CUP -- Move to <row> <col> */
   1692 	case 'f': /* HVP */
   1693 		DEFAULT(csiescseq.arg[0], 1);
   1694 		DEFAULT(csiescseq.arg[1], 1);
   1695 		tmoveato(csiescseq.arg[1]-1, csiescseq.arg[0]-1);
   1696 		break;
   1697 	case 'I': /* CHT -- Cursor Forward Tabulation <n> tab stops */
   1698 		DEFAULT(csiescseq.arg[0], 1);
   1699 		tputtab(csiescseq.arg[0]);
   1700 		break;
   1701 	case 'J': /* ED -- Clear screen */
   1702 		switch (csiescseq.arg[0]) {
   1703 		case 0: /* below */
   1704 			tclearregion(term.c.x, term.c.y, term.col-1, term.c.y);
   1705 			if (term.c.y < term.row-1) {
   1706 				tclearregion(0, term.c.y+1, term.col-1,
   1707 						term.row-1);
   1708 			}
   1709 			break;
   1710 		case 1: /* above */
   1711 			if (term.c.y > 1)
   1712 				tclearregion(0, 0, term.col-1, term.c.y-1);
   1713 			tclearregion(0, term.c.y, term.c.x, term.c.y);
   1714 			break;
   1715 		case 2: /* all */
   1716 			tclearregion(0, 0, term.col-1, term.row-1);
   1717 			break;
   1718 		default:
   1719 			goto unknown;
   1720 		}
   1721 		break;
   1722 	case 'K': /* EL -- Clear line */
   1723 		switch (csiescseq.arg[0]) {
   1724 		case 0: /* right */
   1725 			tclearregion(term.c.x, term.c.y, term.col-1,
   1726 					term.c.y);
   1727 			break;
   1728 		case 1: /* left */
   1729 			tclearregion(0, term.c.y, term.c.x, term.c.y);
   1730 			break;
   1731 		case 2: /* all */
   1732 			tclearregion(0, term.c.y, term.col-1, term.c.y);
   1733 			break;
   1734 		}
   1735 		break;
   1736 	case 'S': /* SU -- Scroll <n> line up */
   1737 		if (csiescseq.priv) break;
   1738 		DEFAULT(csiescseq.arg[0], 1);
   1739 		tscrollup(term.top, csiescseq.arg[0]);
   1740 		break;
   1741 	case 'T': /* SD -- Scroll <n> line down */
   1742 		DEFAULT(csiescseq.arg[0], 1);
   1743 		tscrolldown(term.top, csiescseq.arg[0]);
   1744 		break;
   1745 	case 'L': /* IL -- Insert <n> blank lines */
   1746 		DEFAULT(csiescseq.arg[0], 1);
   1747 		tinsertblankline(csiescseq.arg[0]);
   1748 		break;
   1749 	case 'l': /* RM -- Reset Mode */
   1750 		tsetmode(csiescseq.priv, 0, csiescseq.arg, csiescseq.narg);
   1751 		break;
   1752 	case 'M': /* DL -- Delete <n> lines */
   1753 		DEFAULT(csiescseq.arg[0], 1);
   1754 		tdeleteline(csiescseq.arg[0]);
   1755 		break;
   1756 	case 'X': /* ECH -- Erase <n> char */
   1757 		DEFAULT(csiescseq.arg[0], 1);
   1758 		tclearregion(term.c.x, term.c.y,
   1759 				term.c.x + csiescseq.arg[0] - 1, term.c.y);
   1760 		break;
   1761 	case 'P': /* DCH -- Delete <n> char */
   1762 		DEFAULT(csiescseq.arg[0], 1);
   1763 		tdeletechar(csiescseq.arg[0]);
   1764 		break;
   1765 	case 'Z': /* CBT -- Cursor Backward Tabulation <n> tab stops */
   1766 		DEFAULT(csiescseq.arg[0], 1);
   1767 		tputtab(-csiescseq.arg[0]);
   1768 		break;
   1769 	case 'd': /* VPA -- Move to <row> */
   1770 		DEFAULT(csiescseq.arg[0], 1);
   1771 		tmoveato(term.c.x, csiescseq.arg[0]-1);
   1772 		break;
   1773 	case 'h': /* SM -- Set terminal mode */
   1774 		tsetmode(csiescseq.priv, 1, csiescseq.arg, csiescseq.narg);
   1775 		break;
   1776 	case 'm': /* SGR -- Terminal attribute (color) */
   1777 		tsetattr(csiescseq.arg, csiescseq.narg);
   1778 		break;
   1779 	case 'n': /* DSR -- Device Status Report */
   1780 		switch (csiescseq.arg[0]) {
   1781 		case 5: /* Status Report "OK" `0n` */
   1782 			ttywrite("\033[0n", sizeof("\033[0n") - 1, 0);
   1783 			break;
   1784 		case 6: /* Report Cursor Position (CPR) "<row>;<column>R" */
   1785 			len = snprintf(buf, sizeof(buf), "\033[%i;%iR",
   1786 			               term.c.y+1, term.c.x+1);
   1787 			ttywrite(buf, len, 0);
   1788 			break;
   1789 		default:
   1790 			goto unknown;
   1791 		}
   1792 		break;
   1793 	case 'r': /* DECSTBM -- Set Scrolling Region */
   1794 		if (csiescseq.priv) {
   1795 			goto unknown;
   1796 		} else {
   1797 			DEFAULT(csiescseq.arg[0], 1);
   1798 			DEFAULT(csiescseq.arg[1], term.row);
   1799 			tsetscroll(csiescseq.arg[0]-1, csiescseq.arg[1]-1);
   1800 			tmoveato(0, 0);
   1801 		}
   1802 		break;
   1803 	case 's': /* DECSC -- Save cursor position (ANSI.SYS) */
   1804 		tcursor(CURSOR_SAVE);
   1805 		break;
   1806 	case 'u': /* DECRC -- Restore cursor position (ANSI.SYS) */
   1807 		tcursor(CURSOR_LOAD);
   1808 		break;
   1809 	case ' ':
   1810 		switch (csiescseq.mode[1]) {
   1811 		case 'q': /* DECSCUSR -- Set Cursor Style */
   1812 			if (xsetcursor(csiescseq.arg[0]))
   1813 				goto unknown;
   1814 			break;
   1815 		default:
   1816 			goto unknown;
   1817 		}
   1818 		break;
   1819 	}
   1820 }
   1821 
   1822 void
   1823 csidump(void)
   1824 {
   1825 	size_t i;
   1826 	uint c;
   1827 
   1828 	fprintf(stderr, "ESC[");
   1829 	for (i = 0; i < csiescseq.len; i++) {
   1830 		c = csiescseq.buf[i] & 0xff;
   1831 		if (isprint(c)) {
   1832 			putc(c, stderr);
   1833 		} else if (c == '\n') {
   1834 			fprintf(stderr, "(\\n)");
   1835 		} else if (c == '\r') {
   1836 			fprintf(stderr, "(\\r)");
   1837 		} else if (c == 0x1b) {
   1838 			fprintf(stderr, "(\\e)");
   1839 		} else {
   1840 			fprintf(stderr, "(%02x)", c);
   1841 		}
   1842 	}
   1843 	putc('\n', stderr);
   1844 }
   1845 
   1846 void
   1847 csireset(void)
   1848 {
   1849 	memset(&csiescseq, 0, sizeof(csiescseq));
   1850 }
   1851 
   1852 void
   1853 osc_color_response(int num, int index, int is_osc4)
   1854 {
   1855 	int n;
   1856 	char buf[32];
   1857 	unsigned char r, g, b;
   1858 
   1859 	if (xgetcolor(is_osc4 ? num : index, &r, &g, &b)) {
   1860 		fprintf(stderr, "erresc: failed to fetch %s color %d\n",
   1861 		        is_osc4 ? "osc4" : "osc",
   1862 		        is_osc4 ? num : index);
   1863 		return;
   1864 	}
   1865 
   1866 	n = snprintf(buf, sizeof buf, "\033]%s%d;rgb:%02x%02x/%02x%02x/%02x%02x\007",
   1867 	             is_osc4 ? "4;" : "", num, r, r, g, g, b, b);
   1868 	if (n < 0 || n >= sizeof(buf)) {
   1869 		fprintf(stderr, "error: %s while printing %s response\n",
   1870 		        n < 0 ? "snprintf failed" : "truncation occurred",
   1871 		        is_osc4 ? "osc4" : "osc");
   1872 	} else {
   1873 		ttywrite(buf, n, 1);
   1874 	}
   1875 }
   1876 
   1877 void
   1878 strhandle(void)
   1879 {
   1880 	char *p = NULL, *dec;
   1881 	int j, narg, par;
   1882 	const struct { int idx; char *str; } osc_table[] = {
   1883 		{ defaultfg, "foreground" },
   1884 		{ defaultbg, "background" },
   1885 		{ defaultcs, "cursor" }
   1886 	};
   1887 
   1888 	term.esc &= ~(ESC_STR_END|ESC_STR);
   1889 	strparse();
   1890 	par = (narg = strescseq.narg) ? atoi(strescseq.args[0]) : 0;
   1891 
   1892 	switch (strescseq.type) {
   1893 	case ']': /* OSC -- Operating System Command */
   1894 		switch (par) {
   1895 		case 0:
   1896 			if (narg > 1) {
   1897 				xsettitle(strescseq.args[1]);
   1898 				xseticontitle(strescseq.args[1]);
   1899 			}
   1900 			return;
   1901 		case 1:
   1902 			if (narg > 1)
   1903 				xseticontitle(strescseq.args[1]);
   1904 			return;
   1905 		case 2:
   1906 			if (narg > 1)
   1907 				xsettitle(strescseq.args[1]);
   1908 			return;
   1909 		case 52:
   1910 			if (narg > 2 && allowwindowops) {
   1911 				dec = base64dec(strescseq.args[2]);
   1912 				if (dec) {
   1913 					xsetsel(dec);
   1914 					xclipcopy();
   1915 				} else {
   1916 					fprintf(stderr, "erresc: invalid base64\n");
   1917 				}
   1918 			}
   1919 			return;
   1920 		case 10:
   1921 		case 11:
   1922 		case 12:
   1923 			if (narg < 2)
   1924 				break;
   1925 			p = strescseq.args[1];
   1926 			if ((j = par - 10) < 0 || j >= LEN(osc_table))
   1927 				break; /* shouldn't be possible */
   1928 
   1929 			if (!strcmp(p, "?")) {
   1930 				osc_color_response(par, osc_table[j].idx, 0);
   1931 			} else if (xsetcolorname(osc_table[j].idx, p)) {
   1932 				fprintf(stderr, "erresc: invalid %s color: %s\n",
   1933 				        osc_table[j].str, p);
   1934 			} else {
   1935 				tfulldirt();
   1936 			}
   1937 			return;
   1938 		case 4: /* color set */
   1939 			if (narg < 3)
   1940 				break;
   1941 			p = strescseq.args[2];
   1942 			/* FALLTHROUGH */
   1943 		case 104: /* color reset */
   1944 			j = (narg > 1) ? atoi(strescseq.args[1]) : -1;
   1945 
   1946 			if (p && !strcmp(p, "?")) {
   1947 				osc_color_response(j, 0, 1);
   1948 			} else if (xsetcolorname(j, p)) {
   1949 				if (par == 104 && narg <= 1) {
   1950 					xloadcols();
   1951 					return; /* color reset without parameter */
   1952 				}
   1953 				fprintf(stderr, "erresc: invalid color j=%d, p=%s\n",
   1954 				        j, p ? p : "(null)");
   1955 			} else {
   1956 				/*
   1957 				 * TODO if defaultbg color is changed, borders
   1958 				 * are dirty
   1959 				 */
   1960 				tfulldirt();
   1961 			}
   1962 			return;
   1963 		}
   1964 		break;
   1965 	case 'k': /* old title set compatibility */
   1966 		xsettitle(strescseq.args[0]);
   1967 		return;
   1968 	case 'P': /* DCS -- Device Control String */
   1969 	case '_': /* APC -- Application Program Command */
   1970 	case '^': /* PM -- Privacy Message */
   1971 		return;
   1972 	}
   1973 
   1974 	fprintf(stderr, "erresc: unknown str ");
   1975 	strdump();
   1976 }
   1977 
   1978 void
   1979 strparse(void)
   1980 {
   1981 	int c;
   1982 	char *p = strescseq.buf;
   1983 
   1984 	strescseq.narg = 0;
   1985 	strescseq.buf[strescseq.len] = '\0';
   1986 
   1987 	if (*p == '\0')
   1988 		return;
   1989 
   1990 	while (strescseq.narg < STR_ARG_SIZ) {
   1991 		strescseq.args[strescseq.narg++] = p;
   1992 		while ((c = *p) != ';' && c != '\0')
   1993 			++p;
   1994 		if (c == '\0')
   1995 			return;
   1996 		*p++ = '\0';
   1997 	}
   1998 }
   1999 
   2000 void
   2001 strdump(void)
   2002 {
   2003 	size_t i;
   2004 	uint c;
   2005 
   2006 	fprintf(stderr, "ESC%c", strescseq.type);
   2007 	for (i = 0; i < strescseq.len; i++) {
   2008 		c = strescseq.buf[i] & 0xff;
   2009 		if (c == '\0') {
   2010 			putc('\n', stderr);
   2011 			return;
   2012 		} else if (isprint(c)) {
   2013 			putc(c, stderr);
   2014 		} else if (c == '\n') {
   2015 			fprintf(stderr, "(\\n)");
   2016 		} else if (c == '\r') {
   2017 			fprintf(stderr, "(\\r)");
   2018 		} else if (c == 0x1b) {
   2019 			fprintf(stderr, "(\\e)");
   2020 		} else {
   2021 			fprintf(stderr, "(%02x)", c);
   2022 		}
   2023 	}
   2024 	fprintf(stderr, "ESC\\\n");
   2025 }
   2026 
   2027 void
   2028 strreset(void)
   2029 {
   2030 	strescseq = (STREscape){
   2031 		.buf = xrealloc(strescseq.buf, STR_BUF_SIZ),
   2032 		.siz = STR_BUF_SIZ,
   2033 	};
   2034 }
   2035 
   2036 void
   2037 sendbreak(const Arg *arg)
   2038 {
   2039 	if (tcsendbreak(cmdfd, 0))
   2040 		perror("Error sending break");
   2041 }
   2042 
   2043 void
   2044 tprinter(char *s, size_t len)
   2045 {
   2046 	if (iofd != -1 && xwrite(iofd, s, len) < 0) {
   2047 		perror("Error writing to output file");
   2048 		close(iofd);
   2049 		iofd = -1;
   2050 	}
   2051 }
   2052 
   2053 void
   2054 iso14755(const Arg *arg)
   2055 {
   2056 	FILE *p;
   2057 	char *us, *e, codepoint[9], uc[UTF_SIZ];
   2058 	unsigned long utf32;
   2059 
   2060 	if (!(p = popen(iso14755_cmd, "r")))
   2061 		return;
   2062 
   2063 	us = fgets(codepoint, sizeof(codepoint), p);
   2064 	pclose(p);
   2065 
   2066 	if (!us || *us == '\0' || *us == '-' || strlen(us) > 7)
   2067 		return;
   2068 	if ((utf32 = strtoul(us, &e, 16)) == ULONG_MAX ||
   2069 	    (*e != '\n' && *e != '\0'))
   2070 		return;
   2071 
   2072 	ttywrite(uc, utf8encode(utf32, uc), 1);
   2073 }
   2074 
   2075 void
   2076 toggleprinter(const Arg *arg)
   2077 {
   2078 	term.mode ^= MODE_PRINT;
   2079 }
   2080 
   2081 void
   2082 printscreen(const Arg *arg)
   2083 {
   2084 	tdump();
   2085 }
   2086 
   2087 void
   2088 printsel(const Arg *arg)
   2089 {
   2090 	tdumpsel();
   2091 }
   2092 
   2093 void
   2094 tdumpsel(void)
   2095 {
   2096 	char *ptr;
   2097 
   2098 	if ((ptr = getsel())) {
   2099 		tprinter(ptr, strlen(ptr));
   2100 		free(ptr);
   2101 	}
   2102 }
   2103 
   2104 void
   2105 tdumpline(int n)
   2106 {
   2107 	char buf[UTF_SIZ];
   2108 	const Glyph *bp, *end;
   2109 
   2110 	bp = &term.line[n][0];
   2111 	end = &bp[MIN(tlinelen(n), term.col) - 1];
   2112 	if (bp != end || bp->u != ' ') {
   2113 		for ( ; bp <= end; ++bp)
   2114 			tprinter(buf, utf8encode(bp->u, buf));
   2115 	}
   2116 	tprinter("\n", 1);
   2117 }
   2118 
   2119 void
   2120 tdump(void)
   2121 {
   2122 	int i;
   2123 
   2124 	for (i = 0; i < term.row; ++i)
   2125 		tdumpline(i);
   2126 }
   2127 
   2128 void
   2129 tputtab(int n)
   2130 {
   2131 	uint x = term.c.x;
   2132 
   2133 	if (n > 0) {
   2134 		while (x < term.col && n--)
   2135 			for (++x; x < term.col && !term.tabs[x]; ++x)
   2136 				/* nothing */ ;
   2137 	} else if (n < 0) {
   2138 		while (x > 0 && n++)
   2139 			for (--x; x > 0 && !term.tabs[x]; --x)
   2140 				/* nothing */ ;
   2141 	}
   2142 	term.c.x = LIMIT(x, 0, term.col-1);
   2143 }
   2144 
   2145 void
   2146 tdefutf8(char ascii)
   2147 {
   2148 	if (ascii == 'G')
   2149 		term.mode |= MODE_UTF8;
   2150 	else if (ascii == '@')
   2151 		term.mode &= ~MODE_UTF8;
   2152 }
   2153 
   2154 void
   2155 tdeftran(char ascii)
   2156 {
   2157 	static char cs[] = "0B";
   2158 	static int vcs[] = {CS_GRAPHIC0, CS_USA};
   2159 	char *p;
   2160 
   2161 	if ((p = strchr(cs, ascii)) == NULL) {
   2162 		fprintf(stderr, "esc unhandled charset: ESC ( %c\n", ascii);
   2163 	} else {
   2164 		term.trantbl[term.icharset] = vcs[p - cs];
   2165 	}
   2166 }
   2167 
   2168 void
   2169 tdectest(char c)
   2170 {
   2171 	int x, y;
   2172 
   2173 	if (c == '8') { /* DEC screen alignment test. */
   2174 		for (x = 0; x < term.col; ++x) {
   2175 			for (y = 0; y < term.row; ++y)
   2176 				tsetchar('E', &term.c.attr, x, y);
   2177 		}
   2178 	}
   2179 }
   2180 
   2181 void
   2182 tstrsequence(uchar c)
   2183 {
   2184 	switch (c) {
   2185 	case 0x90:   /* DCS -- Device Control String */
   2186 		c = 'P';
   2187 		break;
   2188 	case 0x9f:   /* APC -- Application Program Command */
   2189 		c = '_';
   2190 		break;
   2191 	case 0x9e:   /* PM -- Privacy Message */
   2192 		c = '^';
   2193 		break;
   2194 	case 0x9d:   /* OSC -- Operating System Command */
   2195 		c = ']';
   2196 		break;
   2197 	}
   2198 	strreset();
   2199 	strescseq.type = c;
   2200 	term.esc |= ESC_STR;
   2201 }
   2202 
   2203 void
   2204 tcontrolcode(uchar ascii)
   2205 {
   2206 	switch (ascii) {
   2207 	case '\t':   /* HT */
   2208 		tputtab(1);
   2209 		return;
   2210 	case '\b':   /* BS */
   2211 		tmoveto(term.c.x-1, term.c.y);
   2212 		return;
   2213 	case '\r':   /* CR */
   2214 		tmoveto(0, term.c.y);
   2215 		return;
   2216 	case '\f':   /* LF */
   2217 	case '\v':   /* VT */
   2218 	case '\n':   /* LF */
   2219 		/* go to first col if the mode is set */
   2220 		tnewline(IS_SET(MODE_CRLF));
   2221 		return;
   2222 	case '\a':   /* BEL */
   2223 		if (term.esc & ESC_STR_END) {
   2224 			/* backwards compatibility to xterm */
   2225 			strhandle();
   2226 		} else {
   2227 			xbell();
   2228 		}
   2229 		break;
   2230 	case '\033': /* ESC */
   2231 		csireset();
   2232 		term.esc &= ~(ESC_CSI|ESC_ALTCHARSET|ESC_TEST);
   2233 		term.esc |= ESC_START;
   2234 		return;
   2235 	case '\016': /* SO (LS1 -- Locking shift 1) */
   2236 	case '\017': /* SI (LS0 -- Locking shift 0) */
   2237 		term.charset = 1 - (ascii - '\016');
   2238 		return;
   2239 	case '\032': /* SUB */
   2240 		tsetchar('?', &term.c.attr, term.c.x, term.c.y);
   2241 		/* FALLTHROUGH */
   2242 	case '\030': /* CAN */
   2243 		csireset();
   2244 		break;
   2245 	case '\005': /* ENQ (IGNORED) */
   2246 	case '\000': /* NUL (IGNORED) */
   2247 	case '\021': /* XON (IGNORED) */
   2248 	case '\023': /* XOFF (IGNORED) */
   2249 	case 0177:   /* DEL (IGNORED) */
   2250 		return;
   2251 	case 0x80:   /* TODO: PAD */
   2252 	case 0x81:   /* TODO: HOP */
   2253 	case 0x82:   /* TODO: BPH */
   2254 	case 0x83:   /* TODO: NBH */
   2255 	case 0x84:   /* TODO: IND */
   2256 		break;
   2257 	case 0x85:   /* NEL -- Next line */
   2258 		tnewline(1); /* always go to first col */
   2259 		break;
   2260 	case 0x86:   /* TODO: SSA */
   2261 	case 0x87:   /* TODO: ESA */
   2262 		break;
   2263 	case 0x88:   /* HTS -- Horizontal tab stop */
   2264 		term.tabs[term.c.x] = 1;
   2265 		break;
   2266 	case 0x89:   /* TODO: HTJ */
   2267 	case 0x8a:   /* TODO: VTS */
   2268 	case 0x8b:   /* TODO: PLD */
   2269 	case 0x8c:   /* TODO: PLU */
   2270 	case 0x8d:   /* TODO: RI */
   2271 	case 0x8e:   /* TODO: SS2 */
   2272 	case 0x8f:   /* TODO: SS3 */
   2273 	case 0x91:   /* TODO: PU1 */
   2274 	case 0x92:   /* TODO: PU2 */
   2275 	case 0x93:   /* TODO: STS */
   2276 	case 0x94:   /* TODO: CCH */
   2277 	case 0x95:   /* TODO: MW */
   2278 	case 0x96:   /* TODO: SPA */
   2279 	case 0x97:   /* TODO: EPA */
   2280 	case 0x98:   /* TODO: SOS */
   2281 	case 0x99:   /* TODO: SGCI */
   2282 		break;
   2283 	case 0x9a:   /* DECID -- Identify Terminal */
   2284 		ttywrite(vtiden, strlen(vtiden), 0);
   2285 		break;
   2286 	case 0x9b:   /* TODO: CSI */
   2287 	case 0x9c:   /* TODO: ST */
   2288 		break;
   2289 	case 0x90:   /* DCS -- Device Control String */
   2290 	case 0x9d:   /* OSC -- Operating System Command */
   2291 	case 0x9e:   /* PM -- Privacy Message */
   2292 	case 0x9f:   /* APC -- Application Program Command */
   2293 		tstrsequence(ascii);
   2294 		return;
   2295 	}
   2296 	/* only CAN, SUB, \a and C1 chars interrupt a sequence */
   2297 	term.esc &= ~(ESC_STR_END|ESC_STR);
   2298 }
   2299 
   2300 /*
   2301  * returns 1 when the sequence is finished and it hasn't to read
   2302  * more characters for this sequence, otherwise 0
   2303  */
   2304 int
   2305 eschandle(uchar ascii)
   2306 {
   2307 	switch (ascii) {
   2308 	case '[':
   2309 		term.esc |= ESC_CSI;
   2310 		return 0;
   2311 	case '#':
   2312 		term.esc |= ESC_TEST;
   2313 		return 0;
   2314 	case '%':
   2315 		term.esc |= ESC_UTF8;
   2316 		return 0;
   2317 	case 'P': /* DCS -- Device Control String */
   2318 	case '_': /* APC -- Application Program Command */
   2319 	case '^': /* PM -- Privacy Message */
   2320 	case ']': /* OSC -- Operating System Command */
   2321 	case 'k': /* old title set compatibility */
   2322 		tstrsequence(ascii);
   2323 		return 0;
   2324 	case 'n': /* LS2 -- Locking shift 2 */
   2325 	case 'o': /* LS3 -- Locking shift 3 */
   2326 		term.charset = 2 + (ascii - 'n');
   2327 		break;
   2328 	case '(': /* GZD4 -- set primary charset G0 */
   2329 	case ')': /* G1D4 -- set secondary charset G1 */
   2330 	case '*': /* G2D4 -- set tertiary charset G2 */
   2331 	case '+': /* G3D4 -- set quaternary charset G3 */
   2332 		term.icharset = ascii - '(';
   2333 		term.esc |= ESC_ALTCHARSET;
   2334 		return 0;
   2335 	case 'D': /* IND -- Linefeed */
   2336 		if (term.c.y == term.bot) {
   2337 			tscrollup(term.top, 1);
   2338 		} else {
   2339 			tmoveto(term.c.x, term.c.y+1);
   2340 		}
   2341 		break;
   2342 	case 'E': /* NEL -- Next line */
   2343 		tnewline(1); /* always go to first col */
   2344 		break;
   2345 	case 'H': /* HTS -- Horizontal tab stop */
   2346 		term.tabs[term.c.x] = 1;
   2347 		break;
   2348 	case 'M': /* RI -- Reverse index */
   2349 		if (term.c.y == term.top) {
   2350 			tscrolldown(term.top, 1);
   2351 		} else {
   2352 			tmoveto(term.c.x, term.c.y-1);
   2353 		}
   2354 		break;
   2355 	case 'Z': /* DECID -- Identify Terminal */
   2356 		ttywrite(vtiden, strlen(vtiden), 0);
   2357 		break;
   2358 	case 'c': /* RIS -- Reset to initial state */
   2359 		treset();
   2360 		resettitle();
   2361 		xloadcols();
   2362 		xsetmode(0, MODE_HIDE);
   2363 		break;
   2364 	case '=': /* DECPAM -- Application keypad */
   2365 		xsetmode(1, MODE_APPKEYPAD);
   2366 		break;
   2367 	case '>': /* DECPNM -- Normal keypad */
   2368 		xsetmode(0, MODE_APPKEYPAD);
   2369 		break;
   2370 	case '7': /* DECSC -- Save Cursor */
   2371 		tcursor(CURSOR_SAVE);
   2372 		break;
   2373 	case '8': /* DECRC -- Restore Cursor */
   2374 		tcursor(CURSOR_LOAD);
   2375 		break;
   2376 	case '\\': /* ST -- String Terminator */
   2377 		if (term.esc & ESC_STR_END)
   2378 			strhandle();
   2379 		break;
   2380 	default:
   2381 		fprintf(stderr, "erresc: unknown sequence ESC 0x%02X '%c'\n",
   2382 			(uchar) ascii, isprint(ascii)? ascii:'.');
   2383 		break;
   2384 	}
   2385 	return 1;
   2386 }
   2387 
   2388 void
   2389 tputc(Rune u)
   2390 {
   2391 	char c[UTF_SIZ];
   2392 	int control;
   2393 	int width, len;
   2394 	Glyph *gp;
   2395 
   2396 	control = ISCONTROL(u);
   2397 	if (u < 127 || !IS_SET(MODE_UTF8)) {
   2398 		c[0] = u;
   2399 		width = len = 1;
   2400 	} else {
   2401 		len = utf8encode(u, c);
   2402 		if (!control && (width = wcwidth(u)) == -1)
   2403 			width = 1;
   2404 	}
   2405 
   2406 	if (IS_SET(MODE_PRINT))
   2407 		tprinter(c, len);
   2408 
   2409 	/*
   2410 	 * STR sequence must be checked before anything else
   2411 	 * because it uses all following characters until it
   2412 	 * receives a ESC, a SUB, a ST or any other C1 control
   2413 	 * character.
   2414 	 */
   2415 	if (term.esc & ESC_STR) {
   2416 		if (u == '\a' || u == 030 || u == 032 || u == 033 ||
   2417 		   ISCONTROLC1(u)) {
   2418 			term.esc &= ~(ESC_START|ESC_STR);
   2419 			term.esc |= ESC_STR_END;
   2420 			goto check_control_code;
   2421 		}
   2422 
   2423 		if (strescseq.len+len >= strescseq.siz) {
   2424 			/*
   2425 			 * Here is a bug in terminals. If the user never sends
   2426 			 * some code to stop the str or esc command, then st
   2427 			 * will stop responding. But this is better than
   2428 			 * silently failing with unknown characters. At least
   2429 			 * then users will report back.
   2430 			 *
   2431 			 * In the case users ever get fixed, here is the code:
   2432 			 */
   2433 			/*
   2434 			 * term.esc = 0;
   2435 			 * strhandle();
   2436 			 */
   2437 			if (strescseq.siz > (SIZE_MAX - UTF_SIZ) / 2)
   2438 				return;
   2439 			strescseq.siz *= 2;
   2440 			strescseq.buf = xrealloc(strescseq.buf, strescseq.siz);
   2441 		}
   2442 
   2443 		memmove(&strescseq.buf[strescseq.len], c, len);
   2444 		strescseq.len += len;
   2445 		return;
   2446 	}
   2447 
   2448 check_control_code:
   2449 	/*
   2450 	 * Actions of control codes must be performed as soon they arrive
   2451 	 * because they can be embedded inside a control sequence, and
   2452 	 * they must not cause conflicts with sequences.
   2453 	 */
   2454 	if (control) {
   2455 		/* in UTF-8 mode ignore handling C1 control characters */
   2456 		if (IS_SET(MODE_UTF8) && ISCONTROLC1(u))
   2457 			return;
   2458 		tcontrolcode(u);
   2459 		/*
   2460 		 * control codes are not shown ever
   2461 		 */
   2462 		if (!term.esc)
   2463 			term.lastc = 0;
   2464 		return;
   2465 	} else if (term.esc & ESC_START) {
   2466 		if (term.esc & ESC_CSI) {
   2467 			csiescseq.buf[csiescseq.len++] = u;
   2468 			if (BETWEEN(u, 0x40, 0x7E)
   2469 					|| csiescseq.len >= \
   2470 					sizeof(csiescseq.buf)-1) {
   2471 				term.esc = 0;
   2472 				csiparse();
   2473 				csihandle();
   2474 			}
   2475 			return;
   2476 		} else if (term.esc & ESC_UTF8) {
   2477 			tdefutf8(u);
   2478 		} else if (term.esc & ESC_ALTCHARSET) {
   2479 			tdeftran(u);
   2480 		} else if (term.esc & ESC_TEST) {
   2481 			tdectest(u);
   2482 		} else {
   2483 			if (!eschandle(u))
   2484 				return;
   2485 			/* sequence already finished */
   2486 		}
   2487 		term.esc = 0;
   2488 		/*
   2489 		 * All characters which form part of a sequence are not
   2490 		 * printed
   2491 		 */
   2492 		return;
   2493 	}
   2494 	if (selected(term.c.x, term.c.y))
   2495 		selclear();
   2496 
   2497 	gp = &term.line[term.c.y][term.c.x];
   2498 	if (IS_SET(MODE_WRAP) && (term.c.state & CURSOR_WRAPNEXT)) {
   2499 		gp->mode |= ATTR_WRAP;
   2500 		tnewline(1);
   2501 		gp = &term.line[term.c.y][term.c.x];
   2502 	}
   2503 
   2504 	if (IS_SET(MODE_INSERT) && term.c.x+width < term.col) {
   2505 		memmove(gp+width, gp, (term.col - term.c.x - width) * sizeof(Glyph));
   2506 		gp->mode &= ~ATTR_WIDE;
   2507 	}
   2508 
   2509 	if (term.c.x+width > term.col) {
   2510 		if (IS_SET(MODE_WRAP))
   2511 			tnewline(1);
   2512 		else
   2513 			tmoveto(term.col - width, term.c.y);
   2514 		gp = &term.line[term.c.y][term.c.x];
   2515 	}
   2516 
   2517 	tsetchar(u, &term.c.attr, term.c.x, term.c.y);
   2518 	term.lastc = u;
   2519 
   2520 	if (width == 2) {
   2521 		gp->mode |= ATTR_WIDE;
   2522 		if (term.c.x+1 < term.col) {
   2523 			if (gp[1].mode == ATTR_WIDE && term.c.x+2 < term.col) {
   2524 				gp[2].u = ' ';
   2525 				gp[2].mode &= ~ATTR_WDUMMY;
   2526 			}
   2527 			gp[1].u = '\0';
   2528 			gp[1].mode = ATTR_WDUMMY;
   2529 		}
   2530 	}
   2531 	if (term.c.x+width < term.col) {
   2532 		tmoveto(term.c.x+width, term.c.y);
   2533 	} else {
   2534 		term.c.state |= CURSOR_WRAPNEXT;
   2535 	}
   2536 }
   2537 
   2538 int
   2539 twrite(const char *buf, int buflen, int show_ctrl)
   2540 {
   2541 	int charsize;
   2542 	Rune u;
   2543 	int n;
   2544 
   2545 	for (n = 0; n < buflen; n += charsize) {
   2546 		if (IS_SET(MODE_UTF8)) {
   2547 			/* process a complete utf8 char */
   2548 			charsize = utf8decode(buf + n, &u, buflen - n);
   2549 			if (charsize == 0)
   2550 				break;
   2551 		} else {
   2552 			u = buf[n] & 0xFF;
   2553 			charsize = 1;
   2554 		}
   2555 		if (show_ctrl && ISCONTROL(u)) {
   2556 			if (u & 0x80) {
   2557 				u &= 0x7f;
   2558 				tputc('^');
   2559 				tputc('[');
   2560 			} else if (u != '\n' && u != '\r' && u != '\t') {
   2561 				u ^= 0x40;
   2562 				tputc('^');
   2563 			}
   2564 		}
   2565 		tputc(u);
   2566 	}
   2567 	return n;
   2568 }
   2569 
   2570 void
   2571 tresize(int col, int row)
   2572 {
   2573 	int i;
   2574 	int minrow = MIN(row, term.row);
   2575 	int mincol = MIN(col, term.col);
   2576 	int *bp;
   2577 	TCursor c;
   2578 
   2579 	if (col < 1 || row < 1) {
   2580 		fprintf(stderr,
   2581 		        "tresize: error resizing to %dx%d\n", col, row);
   2582 		return;
   2583 	}
   2584 
   2585 	/*
   2586 	 * slide screen to keep cursor where we expect it -
   2587 	 * tscrollup would work here, but we can optimize to
   2588 	 * memmove because we're freeing the earlier lines
   2589 	 */
   2590 	for (i = 0; i <= term.c.y - row; i++) {
   2591 		free(term.line[i]);
   2592 		free(term.alt[i]);
   2593 	}
   2594 	/* ensure that both src and dst are not NULL */
   2595 	if (i > 0) {
   2596 		memmove(term.line, term.line + i, row * sizeof(Line));
   2597 		memmove(term.alt, term.alt + i, row * sizeof(Line));
   2598 	}
   2599 	for (i += row; i < term.row; i++) {
   2600 		free(term.line[i]);
   2601 		free(term.alt[i]);
   2602 	}
   2603 
   2604 	/* resize to new height */
   2605 	term.line = xrealloc(term.line, row * sizeof(Line));
   2606 	term.alt  = xrealloc(term.alt,  row * sizeof(Line));
   2607 	term.dirty = xrealloc(term.dirty, row * sizeof(*term.dirty));
   2608 	term.tabs = xrealloc(term.tabs, col * sizeof(*term.tabs));
   2609 
   2610 	/* resize each row to new width, zero-pad if needed */
   2611 	for (i = 0; i < minrow; i++) {
   2612 		term.line[i] = xrealloc(term.line[i], col * sizeof(Glyph));
   2613 		term.alt[i]  = xrealloc(term.alt[i],  col * sizeof(Glyph));
   2614 	}
   2615 
   2616 	/* allocate any new rows */
   2617 	for (/* i = minrow */; i < row; i++) {
   2618 		term.line[i] = xmalloc(col * sizeof(Glyph));
   2619 		term.alt[i] = xmalloc(col * sizeof(Glyph));
   2620 	}
   2621 	if (col > term.col) {
   2622 		bp = term.tabs + term.col;
   2623 
   2624 		memset(bp, 0, sizeof(*term.tabs) * (col - term.col));
   2625 		while (--bp > term.tabs && !*bp)
   2626 			/* nothing */ ;
   2627 		for (bp += tabspaces; bp < term.tabs + col; bp += tabspaces)
   2628 			*bp = 1;
   2629 	}
   2630 	/* update terminal size */
   2631 	term.col = col;
   2632 	term.row = row;
   2633 	/* reset scrolling region */
   2634 	tsetscroll(0, row-1);
   2635 	/* make use of the LIMIT in tmoveto */
   2636 	tmoveto(term.c.x, term.c.y);
   2637 	/* Clearing both screens (it makes dirty all lines) */
   2638 	c = term.c;
   2639 	for (i = 0; i < 2; i++) {
   2640 		if (mincol < col && 0 < minrow) {
   2641 			tclearregion(mincol, 0, col - 1, minrow - 1);
   2642 		}
   2643 		if (0 < col && minrow < row) {
   2644 			tclearregion(0, minrow, col - 1, row - 1);
   2645 		}
   2646 		tswapscreen();
   2647 		tcursor(CURSOR_LOAD);
   2648 	}
   2649 	term.c = c;
   2650 }
   2651 
   2652 void
   2653 resettitle(void)
   2654 {
   2655 	xsettitle(NULL);
   2656 }
   2657 
   2658 void
   2659 drawregion(int x1, int y1, int x2, int y2)
   2660 {
   2661 	int y;
   2662 
   2663 	for (y = y1; y < y2; y++) {
   2664 		if (!term.dirty[y])
   2665 			continue;
   2666 
   2667 		term.dirty[y] = 0;
   2668 		xdrawline(term.line[y], x1, y, x2);
   2669 	}
   2670 }
   2671 
   2672 void
   2673 draw(void)
   2674 {
   2675 	int cx = term.c.x, ocx = term.ocx, ocy = term.ocy;
   2676 
   2677 	if (!xstartdraw())
   2678 		return;
   2679 
   2680 	/* adjust cursor position */
   2681 	LIMIT(term.ocx, 0, term.col-1);
   2682 	LIMIT(term.ocy, 0, term.row-1);
   2683 	if (term.line[term.ocy][term.ocx].mode & ATTR_WDUMMY)
   2684 		term.ocx--;
   2685 	if (term.line[term.c.y][cx].mode & ATTR_WDUMMY)
   2686 		cx--;
   2687 
   2688 	drawregion(0, 0, term.col, term.row);
   2689 	xdrawcursor(cx, term.c.y, term.line[term.c.y][cx],
   2690 			term.ocx, term.ocy, term.line[term.ocy][term.ocx]);
   2691 	term.ocx = cx;
   2692 	term.ocy = term.c.y;
   2693 	xfinishdraw();
   2694 	if (ocx != term.ocx || ocy != term.ocy)
   2695 		xximspot(term.ocx, term.ocy);
   2696 }
   2697 
   2698 void
   2699 redraw(void)
   2700 {
   2701 	tfulldirt();
   2702 	draw();
   2703 }