term.c at 5798447df29a9d668223b56a12ca7403094abd4c · pci.express/flanterm.zig

pci.express / flanterm.zig
Fast and reasonably complete (framebuffer) terminal emulator (Zig fork)
flanterm.zig / term.c
at 5798447df29a9d668223b56a12ca7403094abd4c 42 kB view raw
   1#include <stdint.h>
   2#include <stddef.h>
   3#include <stdbool.h>
   4
   5#include "term.h"
   6
   7static const uint32_t col256[] = {
   8    0x000000, 0x00005f, 0x000087, 0x0000af, 0x0000d7, 0x0000ff, 0x005f00, 0x005f5f,
   9    0x005f87, 0x005faf, 0x005fd7, 0x005fff, 0x008700, 0x00875f, 0x008787, 0x0087af,
  10    0x0087d7, 0x0087ff, 0x00af00, 0x00af5f, 0x00af87, 0x00afaf, 0x00afd7, 0x00afff,
  11    0x00d700, 0x00d75f, 0x00d787, 0x00d7af, 0x00d7d7, 0x00d7ff, 0x00ff00, 0x00ff5f,
  12    0x00ff87, 0x00ffaf, 0x00ffd7, 0x00ffff, 0x5f0000, 0x5f005f, 0x5f0087, 0x5f00af,
  13    0x5f00d7, 0x5f00ff, 0x5f5f00, 0x5f5f5f, 0x5f5f87, 0x5f5faf, 0x5f5fd7, 0x5f5fff,
  14    0x5f8700, 0x5f875f, 0x5f8787, 0x5f87af, 0x5f87d7, 0x5f87ff, 0x5faf00, 0x5faf5f,
  15    0x5faf87, 0x5fafaf, 0x5fafd7, 0x5fafff, 0x5fd700, 0x5fd75f, 0x5fd787, 0x5fd7af,
  16    0x5fd7d7, 0x5fd7ff, 0x5fff00, 0x5fff5f, 0x5fff87, 0x5fffaf, 0x5fffd7, 0x5fffff,
  17    0x870000, 0x87005f, 0x870087, 0x8700af, 0x8700d7, 0x8700ff, 0x875f00, 0x875f5f,
  18    0x875f87, 0x875faf, 0x875fd7, 0x875fff, 0x878700, 0x87875f, 0x878787, 0x8787af,
  19    0x8787d7, 0x8787ff, 0x87af00, 0x87af5f, 0x87af87, 0x87afaf, 0x87afd7, 0x87afff,
  20    0x87d700, 0x87d75f, 0x87d787, 0x87d7af, 0x87d7d7, 0x87d7ff, 0x87ff00, 0x87ff5f,
  21    0x87ff87, 0x87ffaf, 0x87ffd7, 0x87ffff, 0xaf0000, 0xaf005f, 0xaf0087, 0xaf00af,
  22    0xaf00d7, 0xaf00ff, 0xaf5f00, 0xaf5f5f, 0xaf5f87, 0xaf5faf, 0xaf5fd7, 0xaf5fff,
  23    0xaf8700, 0xaf875f, 0xaf8787, 0xaf87af, 0xaf87d7, 0xaf87ff, 0xafaf00, 0xafaf5f,
  24    0xafaf87, 0xafafaf, 0xafafd7, 0xafafff, 0xafd700, 0xafd75f, 0xafd787, 0xafd7af,
  25    0xafd7d7, 0xafd7ff, 0xafff00, 0xafff5f, 0xafff87, 0xafffaf, 0xafffd7, 0xafffff,
  26    0xd70000, 0xd7005f, 0xd70087, 0xd700af, 0xd700d7, 0xd700ff, 0xd75f00, 0xd75f5f,
  27    0xd75f87, 0xd75faf, 0xd75fd7, 0xd75fff, 0xd78700, 0xd7875f, 0xd78787, 0xd787af,
  28    0xd787d7, 0xd787ff, 0xd7af00, 0xd7af5f, 0xd7af87, 0xd7afaf, 0xd7afd7, 0xd7afff,
  29    0xd7d700, 0xd7d75f, 0xd7d787, 0xd7d7af, 0xd7d7d7, 0xd7d7ff, 0xd7ff00, 0xd7ff5f,
  30    0xd7ff87, 0xd7ffaf, 0xd7ffd7, 0xd7ffff, 0xff0000, 0xff005f, 0xff0087, 0xff00af,
  31    0xff00d7, 0xff00ff, 0xff5f00, 0xff5f5f, 0xff5f87, 0xff5faf, 0xff5fd7, 0xff5fff,
  32    0xff8700, 0xff875f, 0xff8787, 0xff87af, 0xff87d7, 0xff87ff, 0xffaf00, 0xffaf5f,
  33    0xffaf87, 0xffafaf, 0xffafd7, 0xffafff, 0xffd700, 0xffd75f, 0xffd787, 0xffd7af,
  34    0xffd7d7, 0xffd7ff, 0xffff00, 0xffff5f, 0xffff87, 0xffffaf, 0xffffd7, 0xffffff,
  35    0x080808, 0x121212, 0x1c1c1c, 0x262626, 0x303030, 0x3a3a3a, 0x444444, 0x4e4e4e,
  36    0x585858, 0x626262, 0x6c6c6c, 0x767676, 0x808080, 0x8a8a8a, 0x949494, 0x9e9e9e,
  37    0xa8a8a8, 0xb2b2b2, 0xbcbcbc, 0xc6c6c6, 0xd0d0d0, 0xdadada, 0xe4e4e4, 0xeeeeee
  38};
  39
  40// Tries to implement this standard for terminfo
  41// https://man7.org/linux/man-pages/man4/console_codes.4.html
  42
  43#define CHARSET_DEFAULT 0
  44#define CHARSET_DEC_SPECIAL 1
  45
  46void term_context_reinit(struct term_context *ctx) {
  47    ctx->tab_size = 8;
  48    ctx->autoflush = true;
  49    ctx->scroll_enabled = true;
  50    ctx->control_sequence = false;
  51    ctx->csi = false;
  52    ctx->escape = false;
  53    ctx->osc = false;
  54    ctx->osc_escape = false;
  55    ctx->rrr = false;
  56    ctx->discard_next = false;
  57    ctx->bold = false;
  58    ctx->bg_bold = false;
  59    ctx->reverse_video = false;
  60    ctx->dec_private = false;
  61    ctx->insert_mode = false;
  62    ctx->unicode_remaining = 0;
  63    ctx->g_select = 0;
  64    ctx->charsets[0] = CHARSET_DEFAULT;
  65    ctx->charsets[1] = CHARSET_DEC_SPECIAL;
  66    ctx->current_charset = 0;
  67    ctx->escape_offset = 0;
  68    ctx->esc_values_i = 0;
  69    ctx->saved_cursor_x = 0;
  70    ctx->saved_cursor_y = 0;
  71    ctx->current_primary = (size_t)-1;
  72    ctx->current_bg = (size_t)-1;
  73    ctx->scroll_top_margin = 0;
  74    ctx->scroll_bottom_margin = ctx->rows;
  75}
  76
  77static void term_putchar(struct term_context *ctx, uint8_t c);
  78
  79void term_write(struct term_context *ctx, const char *buf, size_t count) {
  80    for (size_t i = 0; i < count; i++) {
  81        term_putchar(ctx, buf[i]);
  82    }
  83
  84    if (ctx->autoflush) {
  85        ctx->double_buffer_flush(ctx);
  86    }
  87}
  88
  89static void sgr(struct term_context *ctx) {
  90    size_t i = 0;
  91
  92    if (!ctx->esc_values_i)
  93        goto def;
  94
  95    for (; i < ctx->esc_values_i; i++) {
  96        size_t offset;
  97
  98        if (ctx->esc_values[i] == 0) {
  99def:
 100            if (ctx->reverse_video) {
 101                ctx->reverse_video = false;
 102                ctx->swap_palette(ctx);
 103            }
 104            ctx->bold = false;
 105            ctx->bg_bold = false;
 106            ctx->current_primary = (size_t)-1;
 107            ctx->current_bg = (size_t)-1;
 108            ctx->set_text_bg_default(ctx);
 109            ctx->set_text_fg_default(ctx);
 110            continue;
 111        }
 112
 113        else if (ctx->esc_values[i] == 1) {
 114            ctx->bold = true;
 115            if (ctx->current_primary != (size_t)-1) {
 116                if (!ctx->reverse_video) {
 117                    ctx->set_text_fg_bright(ctx, ctx->current_primary);
 118                } else {
 119                    ctx->set_text_bg_bright(ctx, ctx->current_primary);
 120                }
 121            } else {
 122                if (!ctx->reverse_video) {
 123                    ctx->set_text_fg_default_bright(ctx);
 124                } else {
 125                    ctx->set_text_bg_default_bright(ctx);
 126                }
 127            }
 128            continue;
 129        }
 130
 131        else if (ctx->esc_values[i] == 5) {
 132            ctx->bg_bold = true;
 133            if (ctx->current_bg != (size_t)-1) {
 134                if (!ctx->reverse_video) {
 135                    ctx->set_text_bg_bright(ctx, ctx->current_bg);
 136                } else {
 137                    ctx->set_text_fg_bright(ctx, ctx->current_bg);
 138                }
 139            } else {
 140                if (!ctx->reverse_video) {
 141                    ctx->set_text_bg_default_bright(ctx);
 142                } else {
 143                    ctx->set_text_fg_default_bright(ctx);
 144                }
 145            }
 146            continue;
 147        }
 148
 149        else if (ctx->esc_values[i] == 22) {
 150            ctx->bold = false;
 151            if (ctx->current_primary != (size_t)-1) {
 152                if (!ctx->reverse_video) {
 153                    ctx->set_text_fg(ctx, ctx->current_primary);
 154                } else {
 155                    ctx->set_text_bg(ctx, ctx->current_primary);
 156                }
 157            } else {
 158                if (!ctx->reverse_video) {
 159                    ctx->set_text_fg_default(ctx);
 160                } else {
 161                    ctx->set_text_bg_default(ctx);
 162                }
 163            }
 164            continue;
 165        }
 166
 167        else if (ctx->esc_values[i] == 25) {
 168            ctx->bg_bold = false;
 169            if (ctx->current_bg != (size_t)-1) {
 170                if (!ctx->reverse_video) {
 171                    ctx->set_text_bg(ctx, ctx->current_bg);
 172                } else {
 173                    ctx->set_text_fg(ctx, ctx->current_bg);
 174                }
 175            } else {
 176                if (!ctx->reverse_video) {
 177                    ctx->set_text_bg_default(ctx);
 178                } else {
 179                    ctx->set_text_fg_default(ctx);
 180                }
 181            }
 182            continue;
 183        }
 184
 185        else if (ctx->esc_values[i] >= 30 && ctx->esc_values[i] <= 37) {
 186            offset = 30;
 187            ctx->current_primary = ctx->esc_values[i] - offset;
 188
 189            if (ctx->reverse_video) {
 190                goto set_bg;
 191            }
 192
 193set_fg:
 194            if ((ctx->bold && !ctx->reverse_video)
 195             || (ctx->bg_bold && ctx->reverse_video)) {
 196                ctx->set_text_fg_bright(ctx, ctx->esc_values[i] - offset);
 197            } else {
 198                ctx->set_text_fg(ctx, ctx->esc_values[i] - offset);
 199            }
 200            continue;
 201        }
 202
 203        else if (ctx->esc_values[i] >= 40 && ctx->esc_values[i] <= 47) {
 204            offset = 40;
 205            ctx->current_bg = ctx->esc_values[i] - offset;
 206
 207            if (ctx->reverse_video) {
 208                goto set_fg;
 209            }
 210
 211set_bg:
 212            if ((ctx->bold && ctx->reverse_video)
 213             || (ctx->bg_bold && !ctx->reverse_video)) {
 214                ctx->set_text_bg_bright(ctx, ctx->esc_values[i] - offset);
 215            } else {
 216                ctx->set_text_bg(ctx, ctx->esc_values[i] - offset);
 217            }
 218            continue;
 219        }
 220
 221        else if (ctx->esc_values[i] >= 90 && ctx->esc_values[i] <= 97) {
 222            offset = 90;
 223            ctx->current_primary = ctx->esc_values[i] - offset;
 224
 225            if (ctx->reverse_video) {
 226                goto set_bg_bright;
 227            }
 228
 229set_fg_bright:
 230            ctx->set_text_fg_bright(ctx, ctx->esc_values[i] - offset);
 231            continue;
 232        }
 233
 234        else if (ctx->esc_values[i] >= 100 && ctx->esc_values[i] <= 107) {
 235            offset = 100;
 236            ctx->current_bg = ctx->esc_values[i] - offset;
 237
 238            if (ctx->reverse_video) {
 239                goto set_fg_bright;
 240            }
 241
 242set_bg_bright:
 243            ctx->set_text_bg_bright(ctx, ctx->esc_values[i] - offset);
 244            continue;
 245        }
 246
 247        else if (ctx->esc_values[i] == 39) {
 248            ctx->current_primary = (size_t)-1;
 249
 250            if (ctx->reverse_video) {
 251                ctx->swap_palette(ctx);
 252            }
 253
 254            ctx->set_text_fg_default(ctx);
 255
 256            if (ctx->reverse_video) {
 257                ctx->swap_palette(ctx);
 258            }
 259
 260            continue;
 261        }
 262
 263        else if (ctx->esc_values[i] == 49) {
 264            ctx->current_bg = (size_t)-1;
 265
 266            if (ctx->reverse_video) {
 267                ctx->swap_palette(ctx);
 268            }
 269
 270            ctx->set_text_bg_default(ctx);
 271
 272            if (ctx->reverse_video) {
 273                ctx->swap_palette(ctx);
 274            }
 275
 276            continue;
 277        }
 278
 279        else if (ctx->esc_values[i] == 7) {
 280            if (!ctx->reverse_video) {
 281                ctx->reverse_video = true;
 282                ctx->swap_palette(ctx);
 283            }
 284            continue;
 285        }
 286
 287        else if (ctx->esc_values[i] == 27) {
 288            if (ctx->reverse_video) {
 289                ctx->reverse_video = false;
 290                ctx->swap_palette(ctx);
 291            }
 292            continue;
 293        }
 294
 295        // 256/RGB
 296        else if (ctx->esc_values[i] == 38 || ctx->esc_values[i] == 48) {
 297            bool fg = ctx->esc_values[i] == 38;
 298
 299            i++;
 300            if (i >= ctx->esc_values_i) {
 301                break;
 302            }
 303
 304            switch (ctx->esc_values[i]) {
 305                case 2: { // RGB
 306                    if (i + 3 >= ctx->esc_values_i) {
 307                        goto out;
 308                    }
 309
 310                    uint32_t rgb_value = 0;
 311
 312                    rgb_value |= ctx->esc_values[i + 1] << 16;
 313                    rgb_value |= ctx->esc_values[i + 2] << 8;
 314                    rgb_value |= ctx->esc_values[i + 3];
 315
 316                    i += 3;
 317
 318                    (fg ? ctx->set_text_fg_rgb : ctx->set_text_bg_rgb)(ctx, rgb_value);
 319
 320                    break;
 321                }
 322                case 5: { // 256 colors
 323                    if (i + 1 >= ctx->esc_values_i) {
 324                        goto out;
 325                    }
 326
 327                    uint32_t col = ctx->esc_values[i + 1];
 328
 329                    i++;
 330
 331                    if (col < 8) {
 332                        (fg ? ctx->set_text_fg : ctx->set_text_bg)(ctx, col);
 333                    } else if (col < 16) {
 334                        (fg ? ctx->set_text_fg_bright : ctx->set_text_bg_bright)(ctx, col - 8);
 335                    } else {
 336                        uint32_t rgb_value = col256[col - 16];
 337                        (fg ? ctx->set_text_fg_rgb : ctx->set_text_bg_rgb)(ctx, rgb_value);
 338                    }
 339
 340                    break;
 341                }
 342                default: continue;
 343            }
 344        }
 345    }
 346
 347out:;
 348}
 349
 350static void dec_private_parse(struct term_context *ctx, uint8_t c) {
 351    ctx->dec_private = false;
 352
 353    if (ctx->esc_values_i == 0) {
 354        return;
 355    }
 356
 357    bool set;
 358
 359    switch (c) {
 360        case 'h':
 361            set = true; break;
 362        case 'l':
 363            set = false; break;
 364        default:
 365            return;
 366    }
 367
 368    switch (ctx->esc_values[0]) {
 369        case 25: {
 370            if (set) {
 371                ctx->enable_cursor(ctx);
 372            } else {
 373                ctx->disable_cursor(ctx);
 374            }
 375            return;
 376        }
 377    }
 378
 379    if (ctx->callback != NULL) {
 380        ctx->callback(ctx, TERM_CB_DEC, ctx->esc_values_i, (uintptr_t)ctx->esc_values, c);
 381    }
 382}
 383
 384static void linux_private_parse(struct term_context *ctx) {
 385    if (ctx->esc_values_i == 0) {
 386        return;
 387    }
 388
 389    if (ctx->callback != NULL) {
 390        ctx->callback(ctx, TERM_CB_LINUX, ctx->esc_values_i, (uintptr_t)ctx->esc_values, 0);
 391    }
 392}
 393
 394static void mode_toggle(struct term_context *ctx, uint8_t c) {
 395    if (ctx->esc_values_i == 0) {
 396        return;
 397    }
 398
 399    bool set;
 400
 401    switch (c) {
 402        case 'h':
 403            set = true; break;
 404        case 'l':
 405            set = false; break;
 406        default:
 407            return;
 408    }
 409
 410    switch (ctx->esc_values[0]) {
 411        case 4:
 412            ctx->insert_mode = set; return;
 413    }
 414
 415    if (ctx->callback != NULL) {
 416        ctx->callback(ctx, TERM_CB_MODE, ctx->esc_values_i, (uintptr_t)ctx->esc_values, c);
 417    }
 418}
 419
 420static void osc_parse(struct term_context *ctx, uint8_t c) {
 421    if (ctx->osc_escape && c == '\\') {
 422        goto cleanup;
 423    }
 424
 425    ctx->osc_escape = false;
 426
 427    switch (c) {
 428        case 0x1b:
 429            ctx->osc_escape = true;
 430            break;
 431        case '\a':
 432            goto cleanup;
 433    }
 434
 435    return;
 436
 437cleanup:
 438    ctx->osc_escape = false;
 439    ctx->osc = false;
 440    ctx->escape = false;
 441}
 442
 443static void control_sequence_parse(struct term_context *ctx, uint8_t c) {
 444    if (ctx->escape_offset == 2) {
 445        switch (c) {
 446            case '[':
 447                ctx->discard_next = true;
 448                goto cleanup;
 449            case '?':
 450                ctx->dec_private = true;
 451                return;
 452        }
 453    }
 454
 455    if (c >= '0' && c <= '9') {
 456        if (ctx->esc_values_i == TERM_MAX_ESC_VALUES) {
 457            return;
 458        }
 459        ctx->rrr = true;
 460        ctx->esc_values[ctx->esc_values_i] *= 10;
 461        ctx->esc_values[ctx->esc_values_i] += c - '0';
 462        return;
 463    }
 464
 465    if (ctx->rrr == true) {
 466        ctx->esc_values_i++;
 467        ctx->rrr = false;
 468        if (c == ';')
 469            return;
 470    } else if (c == ';') {
 471        if (ctx->esc_values_i == TERM_MAX_ESC_VALUES) {
 472            return;
 473        }
 474        ctx->esc_values[ctx->esc_values_i] = 0;
 475        ctx->esc_values_i++;
 476        return;
 477    }
 478
 479    size_t esc_default;
 480    switch (c) {
 481        case 'J': case 'K': case 'q':
 482            esc_default = 0; break;
 483        default:
 484            esc_default = 1; break;
 485    }
 486
 487    for (size_t i = ctx->esc_values_i; i < TERM_MAX_ESC_VALUES; i++) {
 488        ctx->esc_values[i] = esc_default;
 489    }
 490
 491    if (ctx->dec_private == true) {
 492        dec_private_parse(ctx, c);
 493        goto cleanup;
 494    }
 495
 496    bool r = ctx->scroll_enabled;
 497    ctx->scroll_enabled = false;
 498    size_t x, y;
 499    ctx->get_cursor_pos(ctx, &x, &y);
 500
 501    switch (c) {
 502        case 'F':
 503            x = 0;
 504            // FALLTHRU
 505        case 'A': {
 506            if (ctx->esc_values[0] > y)
 507                ctx->esc_values[0] = y;
 508            size_t orig_y = y;
 509            size_t dest_y = y - ctx->esc_values[0];
 510            bool will_be_in_scroll_region = false;
 511            if ((ctx->scroll_top_margin >= dest_y && ctx->scroll_top_margin <= orig_y)
 512             || (ctx->scroll_bottom_margin >= dest_y && ctx->scroll_bottom_margin <= orig_y)) {
 513                will_be_in_scroll_region = true;
 514            }
 515            if (will_be_in_scroll_region && dest_y < ctx->scroll_top_margin) {
 516                dest_y = ctx->scroll_top_margin;
 517            }
 518            ctx->set_cursor_pos(ctx, x, dest_y);
 519            break;
 520        }
 521        case 'E':
 522            x = 0;
 523            // FALLTHRU
 524        case 'e':
 525        case 'B': {
 526            if (y + ctx->esc_values[0] > ctx->rows - 1)
 527                ctx->esc_values[0] = (ctx->rows - 1) - y;
 528            size_t orig_y = y;
 529            size_t dest_y = y + ctx->esc_values[0];
 530            bool will_be_in_scroll_region = false;
 531            if ((ctx->scroll_top_margin >= orig_y && ctx->scroll_top_margin <= dest_y)
 532             || (ctx->scroll_bottom_margin >= orig_y && ctx->scroll_bottom_margin <= dest_y)) {
 533                will_be_in_scroll_region = true;
 534            }
 535            if (will_be_in_scroll_region && dest_y >= ctx->scroll_bottom_margin) {
 536                dest_y = ctx->scroll_bottom_margin - 1;
 537            }
 538            ctx->set_cursor_pos(ctx, x, dest_y);
 539            break;
 540        }
 541        case 'a':
 542        case 'C':
 543            if (x + ctx->esc_values[0] > ctx->cols - 1)
 544                ctx->esc_values[0] = (ctx->cols - 1) - x;
 545            ctx->set_cursor_pos(ctx, x + ctx->esc_values[0], y);
 546            break;
 547        case 'D':
 548            if (ctx->esc_values[0] > x)
 549                ctx->esc_values[0] = x;
 550            ctx->set_cursor_pos(ctx, x - ctx->esc_values[0], y);
 551            break;
 552        case 'c':
 553            if (ctx->callback != NULL) {
 554                ctx->callback(ctx, TERM_CB_PRIVATE_ID, 0, 0, 0);
 555            }
 556            break;
 557        case 'd':
 558            ctx->esc_values[0] -= 1;
 559            if (ctx->esc_values[0] >= ctx->rows)
 560                ctx->esc_values[0] = ctx->rows - 1;
 561            ctx->set_cursor_pos(ctx, x, ctx->esc_values[0]);
 562            break;
 563        case 'G':
 564        case '`':
 565            ctx->esc_values[0] -= 1;
 566            if (ctx->esc_values[0] >= ctx->cols)
 567                ctx->esc_values[0] = ctx->cols - 1;
 568            ctx->set_cursor_pos(ctx, ctx->esc_values[0], y);
 569            break;
 570        case 'H':
 571        case 'f':
 572            ctx->esc_values[0] -= 1;
 573            ctx->esc_values[1] -= 1;
 574            if (ctx->esc_values[1] >= ctx->cols)
 575                ctx->esc_values[1] = ctx->cols - 1;
 576            if (ctx->esc_values[0] >= ctx->rows)
 577                ctx->esc_values[0] = ctx->rows - 1;
 578            ctx->set_cursor_pos(ctx, ctx->esc_values[1], ctx->esc_values[0]);
 579            break;
 580        case 'M':
 581            for (size_t i = 0; i < ctx->esc_values[0]; i++) {
 582                ctx->scroll(ctx);
 583            }
 584            break;
 585        case 'L': {
 586            size_t old_scroll_top_margin = ctx->scroll_top_margin;
 587            ctx->scroll_top_margin = y;
 588            for (size_t i = 0; i < ctx->esc_values[0]; i++) {
 589                ctx->revscroll(ctx);
 590            }
 591            ctx->scroll_top_margin = old_scroll_top_margin;
 592            break;
 593        }
 594        case 'n':
 595            switch (ctx->esc_values[0]) {
 596                case 5:
 597                    if (ctx->callback != NULL) {
 598                        ctx->callback(ctx, TERM_CB_STATUS_REPORT, 0, 0, 0);
 599                    }
 600                    break;
 601                case 6:
 602                    if (ctx->callback != NULL) {
 603                        ctx->callback(ctx, TERM_CB_POS_REPORT, x + 1, y + 1, 0);
 604                    }
 605                    break;
 606            }
 607            break;
 608        case 'q':
 609            if (ctx->callback != NULL) {
 610                ctx->callback(ctx, TERM_CB_KBD_LEDS, ctx->esc_values[0], 0, 0);
 611            }
 612            break;
 613        case 'J':
 614            switch (ctx->esc_values[0]) {
 615                case 0: {
 616                    size_t rows_remaining = ctx->rows - (y + 1);
 617                    size_t cols_diff = ctx->cols - (x + 1);
 618                    size_t to_clear = rows_remaining * ctx->cols + cols_diff + 1;
 619                    for (size_t i = 0; i < to_clear; i++) {
 620                        ctx->raw_putchar(ctx, ' ');
 621                    }
 622                    ctx->set_cursor_pos(ctx, x, y);
 623                    break;
 624                }
 625                case 1: {
 626                    ctx->set_cursor_pos(ctx, 0, 0);
 627                    bool b = false;
 628                    for (size_t yc = 0; yc < ctx->rows; yc++) {
 629                        for (size_t xc = 0; xc < ctx->cols; xc++) {
 630                            ctx->raw_putchar(ctx, ' ');
 631                            if (xc == x && yc == y) {
 632                                ctx->set_cursor_pos(ctx, x, y);
 633                                b = true;
 634                                break;
 635                            }
 636                        }
 637                        if (b == true)
 638                            break;
 639                    }
 640                    break;
 641                }
 642                case 2:
 643                case 3:
 644                    ctx->clear(ctx, false);
 645                    break;
 646            }
 647            break;
 648        case '@':
 649            for (size_t i = ctx->cols - 1; ; i--) {
 650                ctx->move_character(ctx, i + ctx->esc_values[0], y, i, y);
 651                ctx->set_cursor_pos(ctx, i, y);
 652                ctx->raw_putchar(ctx, ' ');
 653                if (i == x) {
 654                    break;
 655                }
 656            }
 657            ctx->set_cursor_pos(ctx, x, y);
 658            break;
 659        case 'P':
 660            for (size_t i = x + ctx->esc_values[0]; i < ctx->cols; i++)
 661                ctx->move_character(ctx, i - ctx->esc_values[0], y, i, y);
 662            ctx->set_cursor_pos(ctx, ctx->cols - ctx->esc_values[0], y);
 663            // FALLTHRU
 664        case 'X':
 665            for (size_t i = 0; i < ctx->esc_values[0]; i++)
 666                ctx->raw_putchar(ctx, ' ');
 667            ctx->set_cursor_pos(ctx, x, y);
 668            break;
 669        case 'm':
 670            sgr(ctx);
 671            break;
 672        case 's':
 673            ctx->get_cursor_pos(ctx, &ctx->saved_cursor_x, &ctx->saved_cursor_y);
 674            break;
 675        case 'u':
 676            ctx->set_cursor_pos(ctx, ctx->saved_cursor_x, ctx->saved_cursor_y);
 677            break;
 678        case 'K':
 679            switch (ctx->esc_values[0]) {
 680                case 0: {
 681                    for (size_t i = x; i < ctx->cols; i++)
 682                        ctx->raw_putchar(ctx, ' ');
 683                    ctx->set_cursor_pos(ctx, x, y);
 684                    break;
 685                }
 686                case 1: {
 687                    ctx->set_cursor_pos(ctx, 0, y);
 688                    for (size_t i = 0; i < x; i++)
 689                        ctx->raw_putchar(ctx, ' ');
 690                    break;
 691                }
 692                case 2: {
 693                    ctx->set_cursor_pos(ctx, 0, y);
 694                    for (size_t i = 0; i < ctx->cols; i++)
 695                        ctx->raw_putchar(ctx, ' ');
 696                    ctx->set_cursor_pos(ctx, x, y);
 697                    break;
 698                }
 699            }
 700            break;
 701        case 'r':
 702            ctx->scroll_top_margin = 0;
 703            ctx->scroll_bottom_margin = ctx->rows;
 704            if (ctx->esc_values_i > 0) {
 705                ctx->scroll_top_margin = ctx->esc_values[0] - 1;
 706            }
 707            if (ctx->esc_values_i > 1) {
 708                ctx->scroll_bottom_margin = ctx->esc_values[1];
 709            }
 710            if (ctx->scroll_top_margin >= ctx->rows
 711             || ctx->scroll_bottom_margin > ctx->rows
 712             || ctx->scroll_top_margin >= (ctx->scroll_bottom_margin - 1)) {
 713                ctx->scroll_top_margin = 0;
 714                ctx->scroll_bottom_margin = ctx->rows;
 715            }
 716            ctx->set_cursor_pos(ctx, 0, 0);
 717            break;
 718        case 'l':
 719        case 'h':
 720            mode_toggle(ctx, c);
 721            break;
 722        case ']':
 723            linux_private_parse(ctx);
 724            break;
 725    }
 726
 727    ctx->scroll_enabled = r;
 728
 729cleanup:
 730    ctx->control_sequence = false;
 731    ctx->escape = false;
 732}
 733
 734static void restore_state(struct term_context *ctx) {
 735    ctx->bold = ctx->saved_state_bold;
 736    ctx->bg_bold = ctx->saved_state_bg_bold;
 737    ctx->reverse_video = ctx->saved_state_reverse_video;
 738    ctx->current_charset = ctx->saved_state_current_charset;
 739    ctx->current_primary = ctx->saved_state_current_primary;
 740    ctx->current_bg = ctx->saved_state_current_bg;
 741
 742    ctx->restore_state(ctx);
 743}
 744
 745static void save_state(struct term_context *ctx) {
 746    ctx->save_state(ctx);
 747
 748    ctx->saved_state_bold = ctx->bold;
 749    ctx->saved_state_bg_bold = ctx->bg_bold;
 750    ctx->saved_state_reverse_video = ctx->reverse_video;
 751    ctx->saved_state_current_charset = ctx->current_charset;
 752    ctx->saved_state_current_primary = ctx->current_primary;
 753    ctx->saved_state_current_bg = ctx->current_bg;
 754}
 755
 756static void escape_parse(struct term_context *ctx, uint8_t c) {
 757    ctx->escape_offset++;
 758
 759    if (ctx->osc == true) {
 760        osc_parse(ctx, c);
 761        return;
 762    }
 763
 764    if (ctx->control_sequence == true) {
 765        control_sequence_parse(ctx, c);
 766        return;
 767    }
 768
 769    if (ctx->csi == true) {
 770        ctx->csi = false;
 771        goto is_csi;
 772    }
 773
 774    size_t x, y;
 775    ctx->get_cursor_pos(ctx, &x, &y);
 776
 777    switch (c) {
 778        case ']':
 779            ctx->osc_escape = false;
 780            ctx->osc = true;
 781            return;
 782        case '[':
 783is_csi:
 784            for (size_t i = 0; i < TERM_MAX_ESC_VALUES; i++)
 785                ctx->esc_values[i] = 0;
 786            ctx->esc_values_i = 0;
 787            ctx->rrr = false;
 788            ctx->control_sequence = true;
 789            return;
 790        case '7':
 791            save_state(ctx);
 792            break;
 793        case '8':
 794            restore_state(ctx);
 795            break;
 796        case 'c':
 797            term_context_reinit(ctx);
 798            ctx->clear(ctx, true);
 799            break;
 800        case 'D':
 801            if (y == ctx->scroll_bottom_margin - 1) {
 802                ctx->scroll(ctx);
 803                ctx->set_cursor_pos(ctx, x, y);
 804            } else {
 805                ctx->set_cursor_pos(ctx, x, y + 1);
 806            }
 807            break;
 808        case 'E':
 809            if (y == ctx->scroll_bottom_margin - 1) {
 810                ctx->scroll(ctx);
 811                ctx->set_cursor_pos(ctx, 0, y);
 812            } else {
 813                ctx->set_cursor_pos(ctx, 0, y + 1);
 814            }
 815            break;
 816        case 'M':
 817            // "Reverse linefeed"
 818            if (y == ctx->scroll_top_margin) {
 819                ctx->revscroll(ctx);
 820                ctx->set_cursor_pos(ctx, 0, y);
 821            } else {
 822                ctx->set_cursor_pos(ctx, 0, y - 1);
 823            }
 824            break;
 825        case 'Z':
 826            if (ctx->callback != NULL) {
 827                ctx->callback(ctx, TERM_CB_PRIVATE_ID, 0, 0, 0);
 828            }
 829            break;
 830        case '(':
 831        case ')':
 832            ctx->g_select = c - '\'';
 833            break;
 834        case 0x1b:
 835            if (ctx->in_bootloader == true) {
 836                ctx->raw_putchar(ctx, c);
 837            }
 838            break;
 839    }
 840
 841    ctx->escape = false;
 842}
 843
 844static uint8_t dec_special_to_cp437(uint8_t c) {
 845    switch (c) {
 846        case '`': return 0x04;
 847        case '0': return 0xdb;
 848        case '-': return 0x18;
 849        case ',': return 0x1b;
 850        case '.': return 0x19;
 851        case 'a': return 0xb1;
 852        case 'f': return 0xf8;
 853        case 'g': return 0xf1;
 854        case 'h': return 0xb0;
 855        case 'j': return 0xd9;
 856        case 'k': return 0xbf;
 857        case 'l': return 0xda;
 858        case 'm': return 0xc0;
 859        case 'n': return 0xc5;
 860        case 'q': return 0xc4;
 861        case 's': return 0x5f;
 862        case 't': return 0xc3;
 863        case 'u': return 0xb4;
 864        case 'v': return 0xc1;
 865        case 'w': return 0xc2;
 866        case 'x': return 0xb3;
 867        case 'y': return 0xf3;
 868        case 'z': return 0xf2;
 869        case '~': return 0xfa;
 870        case '_': return 0xff;
 871        case '+': return 0x1a;
 872        case '{': return 0xe3;
 873        case '}': return 0x9c;
 874    }
 875
 876    return c;
 877}
 878
 879// Following wcwidth related code inherited from:
 880// https://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c
 881
 882struct interval {
 883  wchar_t first;
 884  wchar_t last;
 885};
 886
 887/* auxiliary function for binary search in interval table */
 888static int bisearch(wchar_t ucs, const struct interval *table, int max) {
 889  int min = 0;
 890  int mid;
 891
 892  if (ucs < table[0].first || ucs > table[max].last)
 893    return 0;
 894  while (max >= min) {
 895    mid = (min + max) / 2;
 896    if (ucs > table[mid].last)
 897      min = mid + 1;
 898    else if (ucs < table[mid].first)
 899      max = mid - 1;
 900    else
 901      return 1;
 902  }
 903
 904  return 0;
 905}
 906
 907int mk_wcwidth(wchar_t ucs) {
 908  /* sorted list of non-overlapping intervals of non-spacing characters */
 909  /* generated by "uniset +cat=Me +cat=Mn +cat=Cf -00AD +1160-11FF +200B c" */
 910  static const struct interval combining[] = {
 911    { 0x0300, 0x036F }, { 0x0483, 0x0486 }, { 0x0488, 0x0489 },
 912    { 0x0591, 0x05BD }, { 0x05BF, 0x05BF }, { 0x05C1, 0x05C2 },
 913    { 0x05C4, 0x05C5 }, { 0x05C7, 0x05C7 }, { 0x0600, 0x0603 },
 914    { 0x0610, 0x0615 }, { 0x064B, 0x065E }, { 0x0670, 0x0670 },
 915    { 0x06D6, 0x06E4 }, { 0x06E7, 0x06E8 }, { 0x06EA, 0x06ED },
 916    { 0x070F, 0x070F }, { 0x0711, 0x0711 }, { 0x0730, 0x074A },
 917    { 0x07A6, 0x07B0 }, { 0x07EB, 0x07F3 }, { 0x0901, 0x0902 },
 918    { 0x093C, 0x093C }, { 0x0941, 0x0948 }, { 0x094D, 0x094D },
 919    { 0x0951, 0x0954 }, { 0x0962, 0x0963 }, { 0x0981, 0x0981 },
 920    { 0x09BC, 0x09BC }, { 0x09C1, 0x09C4 }, { 0x09CD, 0x09CD },
 921    { 0x09E2, 0x09E3 }, { 0x0A01, 0x0A02 }, { 0x0A3C, 0x0A3C },
 922    { 0x0A41, 0x0A42 }, { 0x0A47, 0x0A48 }, { 0x0A4B, 0x0A4D },
 923    { 0x0A70, 0x0A71 }, { 0x0A81, 0x0A82 }, { 0x0ABC, 0x0ABC },
 924    { 0x0AC1, 0x0AC5 }, { 0x0AC7, 0x0AC8 }, { 0x0ACD, 0x0ACD },
 925    { 0x0AE2, 0x0AE3 }, { 0x0B01, 0x0B01 }, { 0x0B3C, 0x0B3C },
 926    { 0x0B3F, 0x0B3F }, { 0x0B41, 0x0B43 }, { 0x0B4D, 0x0B4D },
 927    { 0x0B56, 0x0B56 }, { 0x0B82, 0x0B82 }, { 0x0BC0, 0x0BC0 },
 928    { 0x0BCD, 0x0BCD }, { 0x0C3E, 0x0C40 }, { 0x0C46, 0x0C48 },
 929    { 0x0C4A, 0x0C4D }, { 0x0C55, 0x0C56 }, { 0x0CBC, 0x0CBC },
 930    { 0x0CBF, 0x0CBF }, { 0x0CC6, 0x0CC6 }, { 0x0CCC, 0x0CCD },
 931    { 0x0CE2, 0x0CE3 }, { 0x0D41, 0x0D43 }, { 0x0D4D, 0x0D4D },
 932    { 0x0DCA, 0x0DCA }, { 0x0DD2, 0x0DD4 }, { 0x0DD6, 0x0DD6 },
 933    { 0x0E31, 0x0E31 }, { 0x0E34, 0x0E3A }, { 0x0E47, 0x0E4E },
 934    { 0x0EB1, 0x0EB1 }, { 0x0EB4, 0x0EB9 }, { 0x0EBB, 0x0EBC },
 935    { 0x0EC8, 0x0ECD }, { 0x0F18, 0x0F19 }, { 0x0F35, 0x0F35 },
 936    { 0x0F37, 0x0F37 }, { 0x0F39, 0x0F39 }, { 0x0F71, 0x0F7E },
 937    { 0x0F80, 0x0F84 }, { 0x0F86, 0x0F87 }, { 0x0F90, 0x0F97 },
 938    { 0x0F99, 0x0FBC }, { 0x0FC6, 0x0FC6 }, { 0x102D, 0x1030 },
 939    { 0x1032, 0x1032 }, { 0x1036, 0x1037 }, { 0x1039, 0x1039 },
 940    { 0x1058, 0x1059 }, { 0x1160, 0x11FF }, { 0x135F, 0x135F },
 941    { 0x1712, 0x1714 }, { 0x1732, 0x1734 }, { 0x1752, 0x1753 },
 942    { 0x1772, 0x1773 }, { 0x17B4, 0x17B5 }, { 0x17B7, 0x17BD },
 943    { 0x17C6, 0x17C6 }, { 0x17C9, 0x17D3 }, { 0x17DD, 0x17DD },
 944    { 0x180B, 0x180D }, { 0x18A9, 0x18A9 }, { 0x1920, 0x1922 },
 945    { 0x1927, 0x1928 }, { 0x1932, 0x1932 }, { 0x1939, 0x193B },
 946    { 0x1A17, 0x1A18 }, { 0x1B00, 0x1B03 }, { 0x1B34, 0x1B34 },
 947    { 0x1B36, 0x1B3A }, { 0x1B3C, 0x1B3C }, { 0x1B42, 0x1B42 },
 948    { 0x1B6B, 0x1B73 }, { 0x1DC0, 0x1DCA }, { 0x1DFE, 0x1DFF },
 949    { 0x200B, 0x200F }, { 0x202A, 0x202E }, { 0x2060, 0x2063 },
 950    { 0x206A, 0x206F }, { 0x20D0, 0x20EF }, { 0x302A, 0x302F },
 951    { 0x3099, 0x309A }, { 0xA806, 0xA806 }, { 0xA80B, 0xA80B },
 952    { 0xA825, 0xA826 }, { 0xFB1E, 0xFB1E }, { 0xFE00, 0xFE0F },
 953    { 0xFE20, 0xFE23 }, { 0xFEFF, 0xFEFF }, { 0xFFF9, 0xFFFB },
 954    { 0x10A01, 0x10A03 }, { 0x10A05, 0x10A06 }, { 0x10A0C, 0x10A0F },
 955    { 0x10A38, 0x10A3A }, { 0x10A3F, 0x10A3F }, { 0x1D167, 0x1D169 },
 956    { 0x1D173, 0x1D182 }, { 0x1D185, 0x1D18B }, { 0x1D1AA, 0x1D1AD },
 957    { 0x1D242, 0x1D244 }, { 0xE0001, 0xE0001 }, { 0xE0020, 0xE007F },
 958    { 0xE0100, 0xE01EF }
 959  };
 960
 961  /* test for 8-bit control characters */
 962  if (ucs == 0)
 963    return 0;
 964  if (ucs < 32 || (ucs >= 0x7f && ucs < 0xa0))
 965    return 1;
 966
 967  /* binary search in table of non-spacing characters */
 968  if (bisearch(ucs, combining,
 969	       sizeof(combining) / sizeof(struct interval) - 1))
 970    return 0;
 971
 972  /* if we arrive here, ucs is not a combining or C0/C1 control character */
 973
 974  return 1 +
 975    (ucs >= 0x1100 &&
 976     (ucs <= 0x115f ||                    /* Hangul Jamo init. consonants */
 977      ucs == 0x2329 || ucs == 0x232a ||
 978      (ucs >= 0x2e80 && ucs <= 0xa4cf &&
 979       ucs != 0x303f) ||                  /* CJK ... Yi */
 980      (ucs >= 0xac00 && ucs <= 0xd7a3) || /* Hangul Syllables */
 981      (ucs >= 0xf900 && ucs <= 0xfaff) || /* CJK Compatibility Ideographs */
 982      (ucs >= 0xfe10 && ucs <= 0xfe19) || /* Vertical forms */
 983      (ucs >= 0xfe30 && ucs <= 0xfe6f) || /* CJK Compatibility Forms */
 984      (ucs >= 0xff00 && ucs <= 0xff60) || /* Fullwidth Forms */
 985      (ucs >= 0xffe0 && ucs <= 0xffe6) ||
 986      (ucs >= 0x20000 && ucs <= 0x2fffd) ||
 987      (ucs >= 0x30000 && ucs <= 0x3fffd)));
 988}
 989
 990// End of https://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c inherited code
 991
 992static int unicode_to_cp437(uint64_t code_point) {
 993    switch (code_point) {
 994        case 0x263a: return 1;
 995        case 0x263b: return 2;
 996        case 0x2665: return 3;
 997        case 0x2666: return 4;
 998        case 0x2663: return 5;
 999        case 0x2660: return 6;
1000        case 0x2022: return 7;
1001        case 0x25d8: return 8;
1002        case 0x25cb: return 9;
1003        case 0x25d9: return 10;
1004        case 0x2642: return 11;
1005        case 0x2640: return 12;
1006        case 0x266a: return 13;
1007        case 0x266b: return 14;
1008        case 0x263c: return 15;
1009        case 0x25ba: return 16;
1010        case 0x25c4: return 17;
1011        case 0x2195: return 18;
1012        case 0x203c: return 19;
1013        case 0x00b6: return 20;
1014        case 0x00a7: return 21;
1015        case 0x25ac: return 22;
1016        case 0x21a8: return 23;
1017        case 0x2191: return 24;
1018        case 0x2193: return 25;
1019        case 0x2192: return 26;
1020        case 0x2190: return 27;
1021        case 0x221f: return 28;
1022        case 0x2194: return 29;
1023        case 0x25b2: return 30;
1024        case 0x25bc: return 31;
1025
1026        case 0x2302: return 127;
1027        case 0x00c7: return 128;
1028        case 0x00fc: return 129;
1029        case 0x00e9: return 130;
1030        case 0x00e2: return 131;
1031        case 0x00e4: return 132;
1032        case 0x00e0: return 133;
1033        case 0x00e5: return 134;
1034        case 0x00e7: return 135;
1035        case 0x00ea: return 136;
1036        case 0x00eb: return 137;
1037        case 0x00e8: return 138;
1038        case 0x00ef: return 139;
1039        case 0x00ee: return 140;
1040        case 0x00ec: return 141;
1041        case 0x00c4: return 142;
1042        case 0x00c5: return 143;
1043        case 0x00c9: return 144;
1044        case 0x00e6: return 145;
1045        case 0x00c6: return 146;
1046        case 0x00f4: return 147;
1047        case 0x00f6: return 148;
1048        case 0x00f2: return 149;
1049        case 0x00fb: return 150;
1050        case 0x00f9: return 151;
1051        case 0x00ff: return 152;
1052        case 0x00d6: return 153;
1053        case 0x00dc: return 154;
1054        case 0x00a2: return 155;
1055        case 0x00a3: return 156;
1056        case 0x00a5: return 157;
1057        case 0x20a7: return 158;
1058        case 0x0192: return 159;
1059        case 0x00e1: return 160;
1060        case 0x00ed: return 161;
1061        case 0x00f3: return 162;
1062        case 0x00fa: return 163;
1063        case 0x00f1: return 164;
1064        case 0x00d1: return 165;
1065        case 0x00aa: return 166;
1066        case 0x00ba: return 167;
1067        case 0x00bf: return 168;
1068        case 0x2310: return 169;
1069        case 0x00ac: return 170;
1070        case 0x00bd: return 171;
1071        case 0x00bc: return 172;
1072        case 0x00a1: return 173;
1073        case 0x00ab: return 174;
1074        case 0x00bb: return 175;
1075        case 0x2591: return 176;
1076        case 0x2592: return 177;
1077        case 0x2593: return 178;
1078        case 0x2502: return 179;
1079        case 0x2524: return 180;
1080        case 0x2561: return 181;
1081        case 0x2562: return 182;
1082        case 0x2556: return 183;
1083        case 0x2555: return 184;
1084        case 0x2563: return 185;
1085        case 0x2551: return 186;
1086        case 0x2557: return 187;
1087        case 0x255d: return 188;
1088        case 0x255c: return 189;
1089        case 0x255b: return 190;
1090        case 0x2510: return 191;
1091        case 0x2514: return 192;
1092        case 0x2534: return 193;
1093        case 0x252c: return 194;
1094        case 0x251c: return 195;
1095        case 0x2500: return 196;
1096        case 0x253c: return 197;
1097        case 0x255e: return 198;
1098        case 0x255f: return 199;
1099        case 0x255a: return 200;
1100        case 0x2554: return 201;
1101        case 0x2569: return 202;
1102        case 0x2566: return 203;
1103        case 0x2560: return 204;
1104        case 0x2550: return 205;
1105        case 0x256c: return 206;
1106        case 0x2567: return 207;
1107        case 0x2568: return 208;
1108        case 0x2564: return 209;
1109        case 0x2565: return 210;
1110        case 0x2559: return 211;
1111        case 0x2558: return 212;
1112        case 0x2552: return 213;
1113        case 0x2553: return 214;
1114        case 0x256b: return 215;
1115        case 0x256a: return 216;
1116        case 0x2518: return 217;
1117        case 0x250c: return 218;
1118        case 0x2588: return 219;
1119        case 0x2584: return 220;
1120        case 0x258c: return 221;
1121        case 0x2590: return 222;
1122        case 0x2580: return 223;
1123        case 0x03b1: return 224;
1124        case 0x00df: return 225;
1125        case 0x0393: return 226;
1126        case 0x03c0: return 227;
1127        case 0x03a3: return 228;
1128        case 0x03c3: return 229;
1129        case 0x00b5: return 230;
1130        case 0x03c4: return 231;
1131        case 0x03a6: return 232;
1132        case 0x0398: return 233;
1133        case 0x03a9: return 234;
1134        case 0x03b4: return 235;
1135        case 0x221e: return 236;
1136        case 0x03c6: return 237;
1137        case 0x03b5: return 238;
1138        case 0x2229: return 239;
1139        case 0x2261: return 240;
1140        case 0x00b1: return 241;
1141        case 0x2265: return 242;
1142        case 0x2264: return 243;
1143        case 0x2320: return 244;
1144        case 0x2321: return 245;
1145        case 0x00f7: return 246;
1146        case 0x2248: return 247;
1147        case 0x00b0: return 248;
1148        case 0x2219: return 249;
1149        case 0x00b7: return 250;
1150        case 0x221a: return 251;
1151        case 0x207f: return 252;
1152        case 0x00b2: return 253;
1153        case 0x25a0: return 254;
1154    }
1155
1156    return -1;
1157}
1158
1159static void term_putchar(struct term_context *ctx, uint8_t c) {
1160    if (ctx->discard_next || (ctx->in_bootloader == false && (c == 0x18 || c == 0x1a))) {
1161        ctx->discard_next = false;
1162        ctx->escape = false;
1163        ctx->csi = false;
1164        ctx->control_sequence = false;
1165        ctx->unicode_remaining = 0;
1166        ctx->osc = false;
1167        ctx->osc_escape = false;
1168        ctx->g_select = 0;
1169        return;
1170    }
1171
1172    if (ctx->unicode_remaining != 0) {
1173        if ((c & 0xc0) != 0x80) {
1174            ctx->unicode_remaining = 0;
1175            goto unicode_error;
1176        }
1177
1178        ctx->unicode_remaining--;
1179        ctx->code_point |= (c & 0x3f) << (6 * ctx->unicode_remaining);
1180        if (ctx->unicode_remaining != 0) {
1181            return;
1182        }
1183
1184        int cc = unicode_to_cp437(ctx->code_point);
1185
1186        if (cc == -1) {
1187            size_t replacement_width = mk_wcwidth(ctx->code_point);
1188            for (size_t i = 0; i < replacement_width; i++) {
1189                ctx->raw_putchar(ctx, 8);
1190            }
1191        } else {
1192            ctx->raw_putchar(ctx, cc);
1193        }
1194        return;
1195    }
1196
1197unicode_error:
1198    if (c >= 0xc0 && c <= 0xf7 && ctx->in_bootloader == false) {
1199        if (c >= 0xc0 && c <= 0xdf) {
1200            ctx->unicode_remaining = 1;
1201            ctx->code_point = (c & 0x1f) << 6;
1202        } else if (c >= 0xe0 && c <= 0xef) {
1203            ctx->unicode_remaining = 2;
1204            ctx->code_point = (c & 0x0f) << (6 * 2);
1205        } else if (c >= 0xf0 && c <= 0xf7) {
1206            ctx->unicode_remaining = 3;
1207            ctx->code_point = (c & 0x07) << (6 * 3);
1208        }
1209        return;
1210    }
1211
1212    if (ctx->escape == true) {
1213        escape_parse(ctx, c);
1214        return;
1215    }
1216
1217    if (ctx->g_select) {
1218        ctx->g_select--;
1219        switch (c) {
1220            case 'B':
1221                ctx->charsets[ctx->g_select] = CHARSET_DEFAULT; break;
1222            case '0':
1223                ctx->charsets[ctx->g_select] = CHARSET_DEC_SPECIAL; break;
1224        }
1225        ctx->g_select = 0;
1226        return;
1227    }
1228
1229    size_t x, y;
1230    ctx->get_cursor_pos(ctx, &x, &y);
1231
1232    switch (c) {
1233        case 0x00:
1234        case 0x7f:
1235            return;
1236        case 0x9b:
1237            ctx->csi = true;
1238            // FALLTHRU
1239        case 0x1b:
1240            ctx->escape_offset = 0;
1241            ctx->escape = true;
1242            return;
1243        case '\t':
1244            if ((x / ctx->tab_size + 1) >= ctx->cols) {
1245                ctx->set_cursor_pos(ctx, ctx->cols - 1, y);
1246                return;
1247            }
1248            ctx->set_cursor_pos(ctx, (x / ctx->tab_size + 1) * ctx->tab_size, y);
1249            return;
1250        case 0x0b:
1251        case 0x0c:
1252        case '\n':
1253            if (y == ctx->scroll_bottom_margin - 1) {
1254                ctx->scroll(ctx);
1255                ctx->set_cursor_pos(ctx, 0, y);
1256            } else {
1257                ctx->set_cursor_pos(ctx, 0, y + 1);
1258            }
1259            return;
1260        case '\b':
1261            ctx->set_cursor_pos(ctx, x - 1, y);
1262            return;
1263        case '\r':
1264            ctx->set_cursor_pos(ctx, 0, y);
1265            return;
1266        case '\a':
1267            // The bell is handled by the kernel
1268            if (ctx->callback != NULL) {
1269                ctx->callback(ctx, TERM_CB_BELL, 0, 0, 0);
1270            }
1271            return;
1272        case 14:
1273            // Move to G1 set
1274            ctx->current_charset = 1;
1275            return;
1276        case 15:
1277            // Move to G0 set
1278            ctx->current_charset = 0;
1279            return;
1280    }
1281
1282    if (ctx->insert_mode == true) {
1283        for (size_t i = ctx->cols - 1; ; i--) {
1284            ctx->move_character(ctx, i + 1, y, i, y);
1285            if (i == x) {
1286                break;
1287            }
1288        }
1289    }
1290
1291    // Translate character set
1292    switch (ctx->charsets[ctx->current_charset]) {
1293        case CHARSET_DEFAULT:
1294            break;
1295        case CHARSET_DEC_SPECIAL:
1296            c = dec_special_to_cp437(c);
1297            break;
1298    }
1299
1300    ctx->raw_putchar(ctx, c);
1301}