vt.c

#include "vt.h"
#include <fcntl.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>

int last = -1;

int kpoll(int w) {
  int c;
  unsigned char d;
  int tries;
  if (last != -1) {
    c = last;
    last = -1;
    return c;
  }
  for (tries = 0; tries != 1; ++tries) {
#ifndef _WIN32
    int flags;
    if (w) {
      flags = fcntl(fileno(stdin), F_GETFL);
      fcntl(fileno(stdin), F_SETFL, flags | O_NONBLOCK);
    }
#endif
    c = read(fileno(stdin), &d, 1);
#ifndef _WIN32
    if (w) {
      fcntl(fileno(stdin), F_SETFL, flags);
    }
#endif
    if (c == 1) {
      /*			printf("\r\nkpoll got %d \r\n", d); */
      return d;
    }
    /*		usleep(1); */
  }
  /*	printf("\r\n--- no char after esc? ---\r\n"); fflush(stdout); */
  return -1;
}

int constat() {
  if (last != -1)
    return 1;
  last = kpoll(1);
  if (last != -1)
    return 1;
  else
    return 0;
}

/* Input FIFO */

#define FIFO_SIZE 4
int stuff[FIFO_SIZE];
int stuff_ptr;

void kpush(int c) {
  if (c != -1 && stuff_ptr != FIFO_SIZE) {
    stuff[stuff_ptr++] = c;
  }
}

int kget(int w) {
  int c;
  if (stuff_ptr) {
    int x;
    c = stuff[0];
    for (x = 0; x != stuff_ptr - 1; ++x) {
      stuff[x] = stuff[x + 1];
    }
    stuff[x] = 0;
    return c;
  }

  c = kpoll(w);
  if (c != 27) {
    return c;
  }
  /* We got ESC.. see if any chars follow */
  c = kpoll(1);

  if (c == -1) { /* Just ESC */
    return 27;
  } else if (c == '[') {
    c = kpoll(0);
    if (c == 'A') { /* Up arrow */
      return 'E' - '@';
    } else if (c == 'B') { /* Down arrow */
      return 'X' - '@';
    } else if (c == 'C') { /* Right arrow */
      return 'D' - '@';
    } else if (c == 'D') { /* Left arrow */
      return 'S' - '@';
    } else if (c == '3') { /* Delete key */
      c = kpoll(0);
      return 'G' - '@';
    } else if (c == '2') { /* Insert key */
      c = kpoll(0);
      return 'V' - '@';
    } else if (c == '5') { /* PgUp */
      c = kpoll(0);
      return 'R' - '@';
    } else if (c == '6') { /* PgDn */
      c = kpoll(0);
      return 'C' - '@';
    } else if (c == '1' || c == '7') { /* Home */
      kpush('s');
      c = kpoll(0);
      return 'Q' - '@';
    } else if (c == '4' || c == '8') { /* End */
      kpush('d');
      c = kpoll(0);
      return 'Q' - '@';
    } else if (c == 'H') { /* Home */
      kpush('s');
      return 'Q' - '@';
    } else if (c == 'F') { /* End */
      kpush('d');
      return 'Q' - '@';
    } else {
      kpush('[');
      kpush(c);
      return 27;
    }
  } else if (c == 'O') {
    c = kpoll(0);
    if (c == 'A') { /* Up arrow */
      return 'E' - '@';
    } else if (c == 'B') { /* Down arrow */
      return 'X' - '@';
    } else if (c == 'C') { /* Right arrow */
      return 'D' - '@';
    } else if (c == 'D') { /* Left arrow */
      return 'S' - '@';
    } else if (c == 'd') { /* Ctrl left arrow (rxvt) */
      return 'A' - '@';
    } else if (c == 'c') { /* Ctrl right arrow (rxvt) */
      return 'F' - '@';
    } else if (c == 'H') { /* Home */
      kpush('s');
      return 'Q' - '@';
    } else if (c == 'F') { /* End */
      kpush('d');
      return 'Q' - '@';
    } else {
      kpush('O');
      kpush(c);
      return 27;
    }
  } else {
    kpush(c);
    return 27;
  }
}

/*
[5~ PgUp
[6~ PgDn
[7~ Home
[8~ End
Od  Ctrl-Ltarw
Oc  Ctrl-Rtarw
*/

void putch(int c) { /* output character without postprocessing */
  write(fileno(stdout), &c, 1);
}

void putmes(const char *s) { write(fileno(stdout), s, strlen(s)); }

void vt52(int c) { /* simple vt52,adm3a => ANSI conversion */
  static int state = 0, x, y;
  char buff[32];
#ifdef DEBUGLOG
  static FILE *log = NULL;
  if (!log)
    log = fopen("cpm.out", "w");
  fputc(c, log);
#endif
  switch (state) {
  case 0:
    switch (c) {
#ifdef VBELL
    case 0x07: /* BEL: flash screen */
      putmes("\033[?5h\033[?5l");
      break;
#endif
    case 0x7f: /* DEL: echo BS, space, BS */
      putmes("\b \b");
      break;
    case 0x1a: /* adm3a clear screen */
    case 0x0c: /* vt52 clear screen */
      putmes("\033[H\033[2J");
      break;
    case 0x1e: /* adm3a cursor home */
      putmes("\033[H");
      break;
    case 0x1b:
      state = 1; /* esc-prefix */
      break;
    case 1:
      state = 2; /* cursor motion prefix */
      break;
    case 2: /* insert line */
      putmes("\033[L");
      break;
    case 3: /* delete line */
      putmes("\033[M");
      break;
    case 0x18:
    case 5: /* clear to eol */
      putmes("\033[K");
      break;
    case 0x12:
    case 0x13:
      break;
    default:
      putch(c);
    }
    break;
  case 1: /* esc was sent */
    switch (c) {
    case 0x1b:
      putch(c);
      break;
    case '=':
    case 'Y':
      state = 2;
      break;
    case 'E': /* insert line */
      putmes("\033[L");
      break;
    case 'R': /* delete line */
      putmes("\033[M");
      break;
    case 'B': /* enable attribute */
      state = 4;
      break;
    case 'C': /* disable attribute */
      state = 5;
      break;
    case 'L': /* set line */
    case 'D': /* delete line */
      state = 6;
      break;
    case '*': /* set pixel */
    case ' ': /* clear pixel */
      state = 8;
      break;
    default: /* some true ANSI sequence? */
      state = 0;
      putch(0x1b);
      putch(c);
    }
    break;
  case 2:
    y = c - ' ' + 1;
    state = 3;
    break;
  case 3:
    x = c - ' ' + 1;
    state = 0;
    sprintf(buff, "\033[%d;%dH", y, x);
    putmes(buff);
    break;
  case 4: /* <ESC>+B prefix */
    state = 0;
    switch (c) {
    case '0': /* start reverse video */
      putmes("\033[7m");
      break;
    case '1': /* start half intensity */
      putmes("\033[1m");
      break;
    case '2': /* start blinking */
      putmes("\033[5m");
      break;
    case '3': /* start underlining */
      putmes("\033[4m");
      break;
    case '4': /* cursor on */
      putmes("\033[?25h");
      break;
    case '6': /* remember cursor position */
      putmes("\033[s");
      break;
    case '5': /* video mode on */
    case '7': /* preserve status line */
      break;
    default:
      putch(0x1b);
      putch('B');
      putch(c);
    }
    break;
  case 5: /* <ESC>+C prefix */
    state = 0;
    switch (c) {
    case '0': /* stop reverse video */
      putmes("\033[27m");
      break;
    case '1': /* stop half intensity */
      putmes("\033[m");
      break;
    case '2': /* stop blinking */
      putmes("\033[25m");
      break;
    case '3': /* stop underlining */
      putmes("\033[24m");
      break;
    case '4': /* cursor off */
      putmes("\033[?25l");
      break;
    case '6': /* restore cursor position */
      putmes("\033[u");
      break;
    case '5': /* video mode off */
    case '7': /* don't preserve status line */
      break;
    default:
      putch(0x1b);
      putch('C');
      putch(c);
    }
    break;
    /* set/clear line/point */
  case 6:
  case 7:
  case 8:
    state++;
    break;
  case 9:
    state = 0;
  }
}