term.c

   1 #include <ctype.h>
   2 #include <errno.h>
   3 #include <fcntl.h>
   4 #include <poll.h>
   5 #include <pty.h>
   6 #include <stdlib.h>
   7 #include <stdio.h>
   8 #include <string.h>
   9 #include <sys/types.h>
  10 #include <unistd.h>
  11 #include "config.h"
  12 #include "pad.h"
  13 #include "util.h"
  14 #include "term.h"
  15
  16 #define MODE_NOCURSOR           0x01
  17 #define MODE_NOWRAP             0x02
  18 #define MODE_ORIGIN             0x04
  19 #define MODE_NOAUTOCR           0x08
  20 #define BIT_SET(i, b, val)      ((val) ? ((i) | (b)) : ((i) & ~(b)))
  21 #define SQRADDR(r, c)           (&screen[(r) * pad_cols() + (c)])
  22
  23 static struct term *term;
  24 static struct square *screen;
  25 static int row, col;
  26 static int fg, bg;
  27 static int top, bot;
  28 static int mode;
  29 static int visible;
  30
  31 #define MAXLINES                (1 << 13)
  32 static int dirty[MAXLINES];
  33 static int lazy;
  34
  35 static void _term_show(int r, int c, int cursor)
  36 {
  37         struct square *sqr = SQRADDR(r, c);
  38         int fgcolor = sqr->c ? sqr->fg : fg;
  39         int bgcolor = sqr->c ? sqr->bg : bg;
  40         if (cursor && !(mode & MODE_NOCURSOR)) {
  41                 int t = fgcolor;
  42                 fgcolor = bgcolor;
  43                 bgcolor = t;
  44         }
  45         if (visible)
  46                 pad_put(sqr->c, r, c, fgcolor, bgcolor);
  47 }
  48
  49 static void _draw_row(int r)
  50 {
  51         int i;
  52         for (i = 0; i < pad_cols(); i++)
  53                 _term_show(r, i, 0);
  54 }
  55
  56 static void lazy_draw(int sr, int er)
  57 {
  58         int i;
  59         if (!visible)
  60                 return;
  61         for (i = sr; i < er; i++) {
  62                 if (lazy)
  63                         dirty[i] = 1;
  64                 else
  65                         _draw_row(i);
  66         }
  67 }
  68
  69 static void lazy_drawcols(int r, int sc, int ec)
  70 {
  71         int i;
  72         if (!visible)
  73                 return;
  74         if (lazy) {
  75                 dirty[r] = 1;
  76         } else {
  77                 for (i = sc; i < ec; i++)
  78                         _term_show(r, i, 0);
  79         }
  80 }
  81
  82 static void lazy_put(int ch, int r, int c)
  83 {
  84         struct square *sqr = SQRADDR(r, c);
  85         sqr->c = ch;
  86         sqr->fg = fg;
  87         sqr->bg = bg;
  88         if (!visible)
  89                 return;
  90         if (lazy)
  91                 dirty[r] = 1;
  92         else
  93                 _term_show(r, c, 0);
  94 }
  95
  96 static void lazy_cursor(int put)
  97 {
  98         if (!visible)
  99                 return;
 100         if (lazy)
 101                 dirty[row] = 1;
 102         else
 103                 _term_show(row, col, put);
 104 }
 105
 106 static void lazy_clean()
 107 {
 108         if (visible)
 109                 memset(dirty, 0, sizeof(*dirty) * MAXLINES);
 110 }
 111
 112 static void lazy_flush()
 113 {
 114         int i;
 115         if (!visible)
 116                 return;
 117         _term_show(row, col, 0);
 118         for (i = 0; i < pad_rows(); i++)
 119                 if (dirty[i])
 120                         _draw_row(i);
 121         lazy_clean();
 122         _term_show(row, col, 1);
 123 }
 124
 125 static int origin(void)
 126 {
 127         return mode & MODE_ORIGIN;
 128 }
 129
 130 static void setsize(void)
 131 {
 132         struct winsize size;
 133         size.ws_col = pad_cols();
 134         size.ws_row = pad_rows();
 135         size.ws_xpixel = 0;
 136         size.ws_ypixel = 0;
 137         ioctl(term->fd, TIOCSWINSZ, &size);
 138 }
 139
 140 #define PTYBUFSIZE              (1 << 13)
 141 static char ptybuf[PTYBUFSIZE];
 142 static int ptylen;
 143 static int ptycur;
 144 static void waitpty(void)
 145 {
 146         struct pollfd ufds[1];
 147         ufds[0].fd = term->fd;
 148         ufds[0].events = POLLIN;
 149         poll(ufds, 1, -1);
 150 }
 151
 152 static int readpty(void)
 153 {
 154         if (ptycur < ptylen)
 155                 return ptybuf[ptycur++];
 156         ptylen = read(term->fd, ptybuf, PTYBUFSIZE);
 157         if (ptylen == -1 && errno == EAGAIN) {
 158                 waitpty();
 159                 ptylen = read(term->fd, ptybuf, PTYBUFSIZE);
 160         }
 161         if (ptylen > 0) {
 162                 ptycur = 1;
 163                 return ptybuf[0];
 164         }
 165         return -1;
 166 }
 167
 168 static void empty_rows(int sr, int er)
 169 {
 170         memset(SQRADDR(sr, 0), 0, (er - sr) * sizeof(*screen) * pad_cols());
 171 }
 172
 173 static void blank_rows(int sr, int er)
 174 {
 175         empty_rows(sr, er);
 176         lazy_draw(sr, er);
 177         lazy_cursor(1);
 178 }
 179
 180 static void scroll_screen(int sr, int nr, int n)
 181 {
 182         lazy_cursor(0);
 183         memmove(SQRADDR(sr + n, 0), SQRADDR(sr, 0),
 184                 nr * pad_cols() * sizeof(*screen));
 185         if (n > 0)
 186                 empty_rows(sr, sr + n);
 187         else
 188                 empty_rows(sr + nr + n, sr + nr);
 189         lazy_draw(MIN(sr, sr + n), MAX(sr + nr, sr + nr + n));
 190         lazy_cursor(1);
 191 }
 192
 193 static void insert_lines(int n)
 194 {
 195         int sr = MAX(top, row);
 196         int nr = bot - row - n;
 197         if (nr > 0)
 198                 scroll_screen(sr, nr, n);
 199 }
 200
 201 static void delete_lines(int n)
 202 {
 203         int r = MAX(top, row);
 204         int sr = r + n;
 205         int nr = bot - r - n;
 206         if (nr > 0)
 207                 scroll_screen(sr, nr, -n);
 208 }
 209
 210 static void move_cursor(int r, int c)
 211 {
 212         int t, b;
 213         lazy_cursor(0);
 214         t = origin() ? top : 0;
 215         b = origin() ? bot : pad_rows();
 216         row = MAX(t, MIN(r, b - 1));
 217         col = MAX(0, MIN(c, pad_cols() - 1));
 218         lazy_cursor(1);
 219 }
 220
 221 static void advance(int dr, int dc, int scrl)
 222 {
 223         int r = row + dr;
 224         int c = col + dc;
 225         if (c >= pad_cols()) {
 226                 if (!scrl || (mode & MODE_NOWRAP)) {
 227                         c = pad_cols() - 1;
 228                 } else {
 229                         r++;
 230                         c = 0;
 231                 }
 232         }
 233         if (r >= bot && scrl) {
 234                 int n = bot - r - 1;
 235                 int nr = (bot - top) + n;
 236                 scroll_screen(top + -n, nr, n);
 237         }
 238         if (r < top && scrl) {
 239                 int n = top - r;
 240                 int nr = (bot - top) - n;
 241                 scroll_screen(top, nr, n);
 242         }
 243         r = MIN(bot - 1, MAX(top, r));
 244         move_cursor(r, MAX(0, c));
 245 }
 246
 247 void term_send(int c)
 248 {
 249         unsigned char b = (unsigned char) c;
 250         if (term->fd)
 251                 write(term->fd, &b, 1);
 252 }
 253
 254 void term_sendstr(char *s)
 255 {
 256         if (term->fd)
 257                 write(term->fd, s, strlen(s));
 258 }
 259
 260 static void setmode(int m)
 261 {
 262         if (m == 0) {
 263                 fg = FGCOLOR;
 264                 bg = BGCOLOR;
 265         }
 266         if (m == 1)
 267                 fg = fg | 0x08;
 268         if (m == 7) {
 269                 int t = fg;
 270                 fg = bg;
 271                 bg = t;
 272         }
 273         if (m >= 30 && m <= 37)
 274                 fg = m - 30;
 275         if (m >= 40 && m <= 47)
 276                 bg = m - 40;
 277 }
 278
 279 static void kill_chars(int sc, int ec)
 280 {
 281         int i;
 282         for (i = sc; i < ec; i++)
 283                 lazy_put(' ', row, i);
 284         lazy_cursor(1);
 285 }
 286
 287 static void move_chars(int sc, int nc, int n)
 288 {
 289         lazy_cursor(0);
 290         memmove(SQRADDR(row, sc + n), SQRADDR(row, sc),
 291                 nc * sizeof(*screen));
 292         if (n > 0)
 293                 memset(SQRADDR(row, sc), 0, n * sizeof(*screen));
 294         else
 295                 memset(SQRADDR(row, pad_rows() + n), 0, -n * sizeof(*screen));
 296         lazy_drawcols(row, MIN(sc, sc + n), pad_cols());
 297         lazy_cursor(1);
 298 }
 299
 300 static void delete_chars(int n)
 301 {
 302         move_chars(col + n, pad_cols(), -n);
 303 }
 304
 305 static void insert_chars(int n)
 306 {
 307         int nc = pad_cols() - col - n;
 308         move_chars(col, nc, n);
 309 }
 310
 311 static void term_blank(void)
 312 {
 313         memset(screen, 0, MAXCHARS * sizeof(*screen));
 314         if (visible) {
 315                 pad_blank(bg);
 316                 lazy_clean();
 317         }
 318 }
 319
 320 static void ctlseq(void);
 321 void term_read(void)
 322 {
 323         ctlseq();
 324         lazy = 1;
 325         while (ptycur < ptylen)
 326                 ctlseq();
 327         lazy_flush();
 328         lazy = 0;
 329 }
 330
 331 void term_exec(char *cmd)
 332 {
 333         bot = pad_rows();
 334         if ((term->pid = forkpty(&term->fd, NULL, NULL, NULL)) == -1) {
 335                 perror("failed to fork");
 336                 term->fd = 0;
 337                 return;
 338         }
 339         if (!term->pid) {
 340                 setenv("TERM", "linux", 1);
 341                 execlp(cmd, cmd, NULL);
 342                 exit(1);
 343         }
 344         fcntl(term->fd, F_SETFD, fcntl(term->fd, F_GETFD) | FD_CLOEXEC);
 345         fcntl(term->fd, F_SETFL, fcntl(term->fd, F_GETFL) | O_NONBLOCK);
 346         setsize();
 347         setmode(0);
 348         term_blank();
 349 }
 350
 351 static void misc_save(struct term_state *state)
 352 {
 353         state->row = row;
 354         state->col = col;
 355         state->fg = fg;
 356         state->bg = bg;
 357         state->top = top;
 358         state->bot = bot;
 359         state->mode = mode;
 360 }
 361
 362 static void misc_load(struct term_state *state)
 363 {
 364         row = state->row;
 365         col = state->col;
 366         fg = state->fg;
 367         bg = state->bg;
 368         top = state->top;
 369         bot = state->bot;
 370         mode = state->mode;
 371 }
 372
 373 void term_save(struct term *term)
 374 {
 375         visible = 0;
 376         misc_save(&term->cur);
 377 }
 378
 379 void term_load(struct term *t, int flags)
 380 {
 381         term = t;
 382         misc_load(&term->cur);
 383         screen = term->screen;
 384         visible = flags;
 385         if (term->fd && flags == TERM_REDRAW) {
 386                 lazy_draw(0, pad_rows());
 387                 lazy_cursor(1);
 388         }
 389         if (!term->fd && flags)
 390                 pad_blank(0);
 391 }
 392
 393 void term_end(void)
 394 {
 395         term->fd = 0;
 396         row = col = 0;
 397         fg = 0;
 398         bg = 0;
 399         term_blank();
 400 }
 401
 402 void set_region(int t, int b)
 403 {
 404         top = MIN(pad_rows(), MAX(0, t - 1));
 405         bot = MIN(pad_rows(), MAX(0, b ? b : pad_rows()));
 406         if (origin())
 407                 move_cursor(top, 0);
 408 }
 409
 410 #include "vt102.c"