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_CURSOR             0x01
  17 #define MODE_WRAP               0x02
  18 #define MODE_ORIGIN             0x04
  19 #define MODE_AUTOCR             0x08
  20 #define MODE_DEFAULT            (MODE_CURSOR | MODE_WRAP)
  21 #define ATTR_BOLD               0x10
  22 #define ATTR_REV                0x20
  23 #define ATTR_ALL                (ATTR_BOLD | ATTR_REV)
  24 #define MODE_WRAPREADY          0x80
  25
  26 #define BIT_SET(i, b, val)      ((val) ? ((i) | (b)) : ((i) & ~(b)))
  27 #define OFFSET(r, c)            ((r) * pad_cols() + (c))
  28
  29 static struct term *term;
  30 static unsigned int *screen;
  31 static unsigned char *fgs, *bgs;
  32 static int row, col;
  33 static unsigned char fg, bg;
  34 static int top, bot;
  35 static unsigned int mode;
  36 static int visible;
  37
  38 #define MAXLINES                (1 << 13)
  39 static int dirty[MAXLINES];
  40 static int lazy;
  41
  42 static unsigned char fgcolor(void)
  43 {
  44         int c = mode & ATTR_REV ? bg : fg;
  45         return mode & ATTR_BOLD ? c | 0x08 : c;
  46 }
  47
  48 static unsigned char bgcolor(void)
  49 {
  50         return mode & ATTR_REV ? fg : bg;
  51 }
  52
  53 static void _term_show(int r, int c, int cursor)
  54 {
  55         int i = OFFSET(r, c);
  56         unsigned char fg = screen[i] ? fgs[i] : fgcolor();
  57         unsigned char bg = screen[i] ? bgs[i] : bgcolor();
  58         if (cursor && mode & MODE_CURSOR) {
  59                 int t = fg;
  60                 fg = bg;
  61                 bg = t;
  62         }
  63         if (visible)
  64                 pad_put(screen[i], r, c, fg, bg);
  65 }
  66
  67 static void _draw_row(int r)
  68 {
  69         int i;
  70         pad_blankrow(r, bgcolor());
  71         for (i = 0; i < pad_cols(); i++) {
  72                 unsigned int c = screen[OFFSET(r, i)];
  73                 if (c && (c != ' ' || bgs[OFFSET(r, i)] != bgcolor()))
  74                         _term_show(r, i, 0);
  75         }
  76 }
  77
  78 static void lazy_draw(int sr, int er)
  79 {
  80         int i;
  81         if (!visible)
  82                 return;
  83         for (i = sr; i < er; i++) {
  84                 if (lazy)
  85                         dirty[i] = 1;
  86                 else
  87                         _draw_row(i);
  88         }
  89 }
  90
  91 static void lazy_drawcols(int r, int sc, int ec)
  92 {
  93         int i;
  94         if (!visible)
  95                 return;
  96         if (lazy) {
  97                 dirty[r] = 1;
  98         } else {
  99                 for (i = sc; i < ec; i++)
 100                         _term_show(r, i, 0);
 101         }
 102 }
 103
 104 static void lazy_put(int ch, int r, int c)
 105 {
 106         int i = OFFSET(r, c);
 107         screen[i] = ch;
 108         fgs[i] = fgcolor();
 109         bgs[i] = bgcolor();
 110         if (!visible)
 111                 return;
 112         if (lazy)
 113                 dirty[r] = 1;
 114         else
 115                 _term_show(r, c, 0);
 116 }
 117
 118 static void lazy_cursor(int put)
 119 {
 120         if (!visible)
 121                 return;
 122         if (lazy)
 123                 dirty[row] = 1;
 124         else
 125                 _term_show(row, col, put);
 126 }
 127
 128 static void lazy_clean()
 129 {
 130         if (visible)
 131                 memset(dirty, 0, sizeof(*dirty) * MAXLINES);
 132 }
 133
 134 static void lazy_flush()
 135 {
 136         int i;
 137         if (!visible)
 138                 return;
 139         _term_show(row, col, 0);
 140         for (i = 0; i < pad_rows(); i++)
 141                 if (dirty[i])
 142                         _draw_row(i);
 143         lazy_clean();
 144         _term_show(row, col, 1);
 145 }
 146
 147 static void term_redraw(void)
 148 {
 149         int i;
 150         for (i = 0; i < pad_rows(); i++)
 151                 _draw_row(i);
 152         _term_show(row, col, 1);
 153 }
 154
 155 static int origin(void)
 156 {
 157         return mode & MODE_ORIGIN;
 158 }
 159
 160 #define PTYBUFSIZE              (1 << 13)
 161 static char ptybuf[PTYBUFSIZE];
 162 static int ptylen;
 163 static int ptycur;
 164 static void waitpty(void)
 165 {
 166         struct pollfd ufds[1];
 167         ufds[0].fd = term->fd;
 168         ufds[0].events = POLLIN;
 169         poll(ufds, 1, -1);
 170 }
 171
 172 static int readpty(void)
 173 {
 174         if (ptycur < ptylen)
 175                 return ptybuf[ptycur++];
 176         if (!term->fd)
 177                 return -1;
 178         ptylen = read(term->fd, ptybuf, PTYBUFSIZE);
 179         if (ptylen == -1 && errno == EAGAIN) {
 180                 waitpty();
 181                 ptylen = read(term->fd, ptybuf, PTYBUFSIZE);
 182         }
 183         if (ptylen > 0) {
 184                 ptycur = 1;
 185                 return ptybuf[0];
 186         }
 187         return -1;
 188 }
 189
 190 static void screen_move(int dst, int src, int n)
 191 {
 192         memmove(screen + dst, screen + src, n * sizeof(*screen));
 193         memmove(fgs + dst, fgs + src, n);
 194         memmove(bgs + dst, bgs + src, n);
 195 }
 196
 197 static void screen_reset(int i, int n)
 198 {
 199         memset(screen + i, 0, n * sizeof(*screen));
 200         memset(fgs + i, fg, n);
 201         memset(bgs + i, bg, n);
 202 }
 203
 204 static void empty_rows(int sr, int er)
 205 {
 206         screen_reset(OFFSET(sr, 0), (er - sr) * pad_cols());
 207 }
 208
 209 static void blank_rows(int sr, int er)
 210 {
 211         empty_rows(sr, er);
 212         lazy_draw(sr, er);
 213         lazy_cursor(1);
 214 }
 215
 216 static void scroll_screen(int sr, int nr, int n)
 217 {
 218         lazy_cursor(0);
 219         screen_move(OFFSET(sr + n, 0), OFFSET(sr, 0), nr * pad_cols());
 220         if (n > 0)
 221                 empty_rows(sr, sr + n);
 222         else
 223                 empty_rows(sr + nr + n, sr + nr);
 224         lazy_draw(MIN(sr, sr + n), MAX(sr + nr, sr + nr + n));
 225         lazy_cursor(1);
 226 }
 227
 228 static void insert_lines(int n)
 229 {
 230         int sr = MAX(top, row);
 231         int nr = bot - row - n;
 232         if (nr > 0)
 233                 scroll_screen(sr, nr, n);
 234 }
 235
 236 static void delete_lines(int n)
 237 {
 238         int r = MAX(top, row);
 239         int sr = r + n;
 240         int nr = bot - r - n;
 241         if (nr > 0)
 242                 scroll_screen(sr, nr, -n);
 243 }
 244
 245 static void move_cursor(int r, int c)
 246 {
 247         int t, b;
 248         lazy_cursor(0);
 249         t = origin() ? top : 0;
 250         b = origin() ? bot : pad_rows();
 251         row = MAX(t, MIN(r, b - 1));
 252         col = MAX(0, MIN(c, pad_cols() - 1));
 253         lazy_cursor(1);
 254         mode = BIT_SET(mode, MODE_WRAPREADY, 0);
 255 }
 256
 257 static void advance(int dr, int dc, int scrl)
 258 {
 259         int r = row + dr;
 260         int c = col + dc;
 261         if (r >= bot && scrl) {
 262                 int n = bot - r - 1;
 263                 int nr = (bot - top) + n;
 264                 scroll_screen(top + -n, nr, n);
 265         }
 266         if (r < top && scrl) {
 267                 int n = top - r;
 268                 int nr = (bot - top) - n;
 269                 scroll_screen(top, nr, n);
 270         }
 271         r = MIN(bot - 1, MAX(top, r));
 272         c = MIN(pad_cols() - 1, MAX(0, c));
 273         move_cursor(r, c);
 274 }
 275
 276 static void insertchar(int c)
 277 {
 278         int wrapready;
 279         if (mode & MODE_WRAPREADY)
 280                 advance(1, -col, 1);
 281         lazy_put(c, row, col);
 282         wrapready = col == pad_cols() - 1;
 283         advance(0, 1, 1);
 284         if (wrapready)
 285                 mode = BIT_SET(mode, MODE_WRAPREADY, 1);
 286 }
 287
 288 void term_send(int c)
 289 {
 290         unsigned char b = (unsigned char) c;
 291         if (term->fd)
 292                 write(term->fd, &b, 1);
 293 }
 294
 295 static void term_sendstr(char *s)
 296 {
 297         if (term->fd)
 298                 write(term->fd, s, strlen(s));
 299 }
 300
 301 static void setattr(int m)
 302 {
 303         switch (m) {
 304         case 0:
 305                 fg = FGCOLOR;
 306                 bg = BGCOLOR;
 307                 mode &= ~ATTR_ALL;
 308                 break;
 309         case 1:
 310                 mode |= ATTR_BOLD;
 311                 break;
 312         case 7:
 313                 mode |= ATTR_REV;
 314                 break;
 315         case 22:
 316                 mode &= ~ATTR_BOLD;
 317                 break;
 318         case 27:
 319                 mode &= ~ATTR_REV;
 320                 break;
 321         default:
 322                 if ((m / 10) == 3)
 323                         fg = m > 37 ? FGCOLOR : m - 30;
 324                 if ((m / 10) == 4)
 325                         bg = m > 47 ? BGCOLOR : m - 40;
 326         }
 327 }
 328
 329 static void kill_chars(int sc, int ec)
 330 {
 331         int i;
 332         for (i = sc; i < ec; i++)
 333                 lazy_put(' ', row, i);
 334         lazy_cursor(1);
 335 }
 336
 337 static void move_chars(int sc, int nc, int n)
 338 {
 339         lazy_cursor(0);
 340         screen_move(OFFSET(row, sc + n), OFFSET(row, sc), nc);
 341         if (n > 0)
 342                 screen_reset(OFFSET(row, sc), n);
 343         else
 344                 screen_reset(OFFSET(row, pad_cols() + n), -n);
 345         lazy_drawcols(row, MIN(sc, sc + n), pad_cols());
 346         lazy_cursor(1);
 347 }
 348
 349 static void delete_chars(int n)
 350 {
 351         int sc = col + n;
 352         int nc = pad_cols() - sc;
 353         move_chars(sc, nc, -n);
 354 }
 355
 356 static void insert_chars(int n)
 357 {
 358         int nc = pad_cols() - col - n;
 359         move_chars(col, nc, n);
 360 }
 361
 362 static void term_blank(void)
 363 {
 364         screen_reset(0, pad_rows() * pad_cols());
 365         if (visible) {
 366                 pad_blank(bgcolor());
 367                 lazy_clean();
 368         }
 369 }
 370
 371 static void ctlseq(void);
 372 void term_read(void)
 373 {
 374         ctlseq();
 375         while (ptycur < ptylen) {
 376                 if (ptylen - ptycur > 15)
 377                         lazy = 1;
 378                 ctlseq();
 379         }
 380         if (lazy)
 381                 lazy_flush();
 382         lazy = 0;
 383 }
 384
 385 static void term_reset(void)
 386 {
 387         row = col = 0;
 388         top = 0;
 389         bot = pad_rows();
 390         mode = MODE_DEFAULT;
 391         setattr(0);
 392         term_blank();
 393 }
 394
 395 void term_exec(char *cmd)
 396 {
 397         struct winsize size;
 398         size.ws_col = pad_cols();
 399         size.ws_row = pad_rows();
 400         size.ws_xpixel = 0;
 401         size.ws_ypixel = 0;
 402         memset(term, 0, sizeof(*term));
 403         if ((term->pid = forkpty(&term->fd, NULL, NULL, &size)) == -1) {
 404                 perror("failed to fork");
 405                 term->fd = 0;
 406                 return;
 407         }
 408         if (!term->pid) {
 409                 setenv("TERM", "linux", 1);
 410                 execlp(cmd, cmd, NULL);
 411                 exit(1);
 412         }
 413         fcntl(term->fd, F_SETFD, fcntl(term->fd, F_GETFD) | FD_CLOEXEC);
 414         fcntl(term->fd, F_SETFL, fcntl(term->fd, F_GETFL) | O_NONBLOCK);
 415         term_reset();
 416 }
 417
 418 static void misc_save(struct term_state *state)
 419 {
 420         state->row = row;
 421         state->col = col;
 422         state->fg = fg;
 423         state->bg = bg;
 424         state->mode = mode;
 425 }
 426
 427 static void misc_load(struct term_state *state)
 428 {
 429         row = state->row;
 430         col = state->col;
 431         fg = state->fg;
 432         bg = state->bg;
 433         mode = state->mode;
 434 }
 435
 436 void term_save(struct term *term)
 437 {
 438         visible = 0;
 439         misc_save(&term->cur);
 440         term->top = top;
 441         term->bot = bot;
 442 }
 443
 444 void term_load(struct term *t, int flags)
 445 {
 446         term = t;
 447         misc_load(&term->cur);
 448         screen = term->screen;
 449         fgs = term->fgs;
 450         bgs = term->bgs;
 451         visible = flags;
 452         top = term->top;
 453         bot = term->bot;
 454         if (flags == TERM_REDRAW) {
 455                 if (term->fd)
 456                         term_redraw();
 457                 else
 458                         pad_blank(0);
 459         }
 460 }
 461
 462 void term_end(void)
 463 {
 464         if (term->fd)
 465                 close(term->fd);
 466         memset(term, 0, sizeof(*term));
 467         term_load(term, visible ? TERM_REDRAW : TERM_HIDDEN);
 468 }
 469
 470 static void set_region(int t, int b)
 471 {
 472         top = MIN(pad_rows(), MAX(0, t - 1));
 473         bot = MIN(pad_rows(), MAX(0, b ? b : pad_rows()));
 474         if (origin())
 475                 move_cursor(top, 0);
 476 }
 477
 478 void term_screenshot(void)
 479 {
 480         FILE *fp = fopen(SCREENSHOT, "w");
 481         int i, j;
 482         for (i = 0; i < pad_rows(); i++) {
 483                 for (j = 0; j < pad_cols(); j++) {
 484                         int c = screen[OFFSET(i, j)];
 485                         fputc(c ? c : ' ', fp);
 486                 }
 487                 fputc('\n', fp);
 488         }
 489         fclose(fp);
 490 }
 491
 492 #include "vt102.c"