WebSVN – SvarDOS – Diff – /sved/trunk/sved.c


/* Sved, the SvarDOS editor
 *
 * Copyright (C) 2023 Mateusz Viste
 *
 * Sved is released under the terms of the MIT license.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */
 
#include <dos.h>      /* _dos_open(), _dos_read(), _dos_close(), ... */
#include <fcntl.h>    /* O_RDONLY, O_WRONLY */
#include <string.h>
 
#include "mdr\bios.h"
#include "mdr\cout.h"
#include "mdr\dos.h"
 
#include "svarlang\svarlang.h"
 
 
#define PVER "2023.0"
#define PDATE "2023"
 
/*****************************************************************************
 * global variables and definitions                                          *
 *****************************************************************************/
 
/* preload the mono scheme (to be overloaded at runtime if color adapter present) */
static unsigned char SCHEME_TEXT   = 0x07,
                     SCHEME_MENU   = 0x70,
                     SCHEME_MENU_CUR= 0x0f,
                     SCHEME_MENU_SEL= 0x00,
                     SCHEME_STBAR1 = 0x70,
                     SCHEME_STBAR2 = 0x70, /* greyed out information */
                     SCHEME_STBAR3 = 0x70, /* query */
                     SCHEME_SCROLL = 0x70,
                     SCHEME_MSG    = 0x70,
                     SCHEME_ERR    = 0x70;
 
static unsigned char screenw, screenh, screenlastrow, screenlastcol;
static unsigned char glob_monomode, glob_tablessmode;
 
static struct {
    unsigned char from;
    unsigned char to;
    unsigned char statusbar;
} uidirty = {0, 0xff, 1}; /* make sure to redraw entire UI at first run */
 
#define SCROLL_CURSOR 0xB1
 
struct line {
  unsigned short len;
  struct line far *next;
  struct line far *prev;
  char payload[1];
};
 
struct file {
  struct line far *cursor;
  unsigned short xoffset;
  unsigned short cursorposx;
  unsigned short cursorposy;
  unsigned short totlines;
  unsigned short curline;
  unsigned short curline_prev;
  char lfonly;   /* set if line endings are LF (CR/LF otherwise) */
  char modflag;  /* non-zero if file has been modified since last save */
  char modflagprev;
  char fname[128];
};
 
 
/*****************************************************************************
 * functions                                                                 *
 *****************************************************************************/
 
static struct line far *line_calloc(unsigned short siz) {
  struct line far *res;
  unsigned int seg;
  if (_dos_allocmem((sizeof(struct line) + siz + 15) / 16, &seg) != 0) return(NULL);
  res = MK_FP(seg, 0);
  _fmemset(res, 0, sizeof(struct line) + siz);
  return(MK_FP(seg, 0));
}
 
 
static void line_free(struct line far *ptr) {
  _dos_freemem(FP_SEG(ptr));
}
 
 
static int curline_resize(struct file far *db, unsigned short newsiz) {
  unsigned int maxavail;
  struct line far *newptr;
 
  /* try resizing the block (much faster) */
  if (_dos_setblock((sizeof(struct line) + newsiz + 15) / 16, FP_SEG(db->cursor), &maxavail) == 0) return(0);
 
  /* create a new block and copy data over */
  newptr = line_calloc(newsiz);
  if (newptr == NULL) return(-1);
  _fmemmove(newptr, db->cursor, sizeof(struct line) + db->cursor->len);
 
  /* rewire the linked list */
  db->cursor = newptr;
  if (newptr->next) newptr->next->prev = newptr;
  if (newptr->prev) newptr->prev->next = newptr;
 
  return(0);
}
 
 
/* adds a new line at cursor position into file linked list and advance cursor
 * returns non-zero on error */
static int line_add(struct file *db, const char far *line, unsigned short slen) {
  struct line far *l;
 
  l = line_calloc(slen);
  if (l == NULL) return(-1);
 
  l->prev = db->cursor;
  if (db->cursor) {
    l->next = db->cursor->next;
    db->cursor->next = l;
    l->next->prev = l;
  }
  db->cursor = l;
  if (slen > 0) {
    _fmemmove(l->payload, line, slen);
    l->len = slen;
  }
 
  db->totlines += 1;
  db->curline += 1;
 
  return(0);
}
 
 
static void ui_getstring(const char *query, char *s, unsigned short maxlen) {
  unsigned short len = 0;
  unsigned char y, x;
  int k;
 
  if (maxlen == 0) return;
  maxlen--; /* make room for the nul terminator */
 
  y = screenlastrow;
 
  /* print query string */
  x = mdr_cout_str(y, 0, query, SCHEME_STBAR3, 40);
  mdr_cout_char_rep(y, x++, ' ', SCHEME_STBAR3, screenw - x);
 
  for (;;) {
    mdr_cout_locate(y, x + len);
    k = mdr_dos_getkey2();
 
    switch (k) {
      case 0x1b: /* ESC */
        s[0] = 0;
        return;
      case '\r':
        s[len] = 0;
        return;
      case 0x08: /* BKSPC */
        if (len > 0) {
          len--;
          mdr_cout_char(y, x + len, ' ', SCHEME_STBAR3);
        }
        break;
      default:
        if ((k <= 0xff) && (k >= ' ') && (len < maxlen)) {
          mdr_cout_char(y, x + len, k, SCHEME_STBAR3);
          s[len++] = k;
        }
    }
  }
 
}
 
 
/* append a nul-terminated string to line at cursor position */
static int line_append(struct file *f, const char far *buf, unsigned short len) {
  if (sizeof(struct line) + f->cursor->len + len < len) goto ERR; /* overflow check */
  if (curline_resize(f, f->cursor->len + len) != 0) goto ERR;
 
  _fmemmove(f->cursor->payload + f->cursor->len, buf, len);
  f->cursor->len += len;
 
  return(0);
  ERR:
  return(-1);
}
 
 
static void db_rewind(struct file *db) {
  if (db->cursor == NULL) return;
  while (db->cursor->prev) db->cursor = db->cursor->prev;
  db->curline = 0;
}
 
 
static void ui_statusbar(const struct file *db, unsigned char slotnum) {
  const char *s = svarlang_strid(0); /* ESC=MENU */
  unsigned short helpcol = screenw - strlen(s);
  unsigned short maxfnlen = helpcol - 14;
 
  /* slot number (guaranteed to be 0-9) */
  {
    char slot[4] = "#00";
    if (slotnum == 9) {
      slot[1] = '1';
    } else {
      slotnum++;
      slot[2] += slotnum;
    }
    mdr_cout_str(screenlastrow, 0, slot, SCHEME_STBAR2, 3);
  }
 
  /* fill rest of status bar with background */
  mdr_cout_char_rep(screenlastrow, 3, ' ', SCHEME_STBAR1, helpcol - 3);
 
  /* filename and modflag */
  {
    const char *fn;
    unsigned short x;
    if (db->fname[0] == 0) {
      fn = svarlang_str(0, 1); /* "UNTITLED" */
    } else {
      /* display filename up to maxfnlen chars */
      fn = db->fname;
      x = strlen(fn);
      if (x > maxfnlen) fn += x - maxfnlen;
    }
    x = mdr_cout_str(screenlastrow, 4, fn, SCHEME_STBAR1, maxfnlen);
    if (db->modflag) mdr_cout_char(screenlastrow, 5 + x, '!', SCHEME_STBAR2);
  }
 
  /* eol type */
  {
    const char *eoltype = "CRLF";
    if (db->lfonly) eoltype += 2;
    mdr_cout_str(screenlastrow, helpcol - 6, eoltype, SCHEME_STBAR1, 5);
  }
 
  /* line numbers */
  {
    unsigned short x;
    unsigned char count = 0;
    unsigned short col = helpcol - 9;
 
    x = db->totlines;
    AGAIN:
    do {
      mdr_cout_char(screenlastrow, col--, '0' + (x % 10), SCHEME_STBAR1);
      x /= 10;
 
    } while (x);
    /* redo same exercise, but printing the current line now */
    if (count == 0) {
      count = 1;
      mdr_cout_char(screenlastrow, col--, '/', SCHEME_STBAR1);
 
      x = 1 + db->curline;
      goto AGAIN;
    }
 
  }
 
  mdr_cout_str(screenlastrow, helpcol, s, SCHEME_STBAR2, 40);
}
 
 
static void ui_msg(const char *msg1, const char *msg2, unsigned char attr) {
  unsigned short x, y, msglen, i;
  unsigned short msg2flag = 0;
 
  msglen = strlen(msg1);
  if (msg2) {
    msg2flag = 1;
    i = strlen(msg2);
    if (i > msglen) msglen = i;
  }
 
  y = (screenh - 6) >> 1;
  x = (screenw - msglen - 4) >> 1;
  for (i = y+2+msg2flag; i >= y; i--) mdr_cout_char_rep(i, x, ' ', attr, msglen + 2);
  x++;
 
  mdr_cout_str(y+1, x, msg1, attr, msglen);
  if (msg2) mdr_cout_str(y+2, x, msg2, attr, msglen);
 
  if (uidirty.from > y) uidirty.from = y;
  if (uidirty.to < y+4) uidirty.to = y+4;
}
 
 
static unsigned char ui_confirm_if_unsaved(const struct file *db) {
  unsigned char r = 0;
  if (db->modflag == 0) return(0);
 
  mdr_cout_cursor_hide();
 
  /* if file has been modified then ask for confirmation */
  ui_msg(svarlang_str(0,4), svarlang_str(0,5), SCHEME_MSG);
  if (mdr_dos_getkey2() != '\r') r = 1;
 
  mdr_cout_cursor_show();
 
  return(r);
}
 
 
static void ui_refresh(const struct file *db) {
  unsigned char x;
  const struct line far *l;
  unsigned char y = db->cursorposy;
 
  /* quit early if nothing to refresh */
  if (uidirty.from == 0xff) return;
 
#ifdef DBG_REFRESH
  static char m = 'a';
  m++;
  if (m > 'z') m = 'a';
#endif
 
  /* rewind cursor line to first line that needs redrawing */
  for (l = db->cursor; y > uidirty.from; y--) l = l->prev;
 
  /* iterate over lines and redraw whatever needs to be redrawn */
  for (; l != NULL; l = l->next, y++) {
 
    /* skip lines that do not need to be refreshed */
    if (y < uidirty.from) continue;
    if (y > uidirty.to) break;
 
    x = 0;
    if (db->xoffset < l->len) {
      unsigned char i, limit;
      if (l->len - db->xoffset < screenw) {
        limit = l->len;
      } else {
        limit = db->xoffset + screenlastcol;
      }
      for (i = db->xoffset; i < limit; i++) mdr_cout_char(y, x++, l->payload[i], SCHEME_TEXT);
    }
 
    /* write empty spaces until end of line */
    if (x < screenlastcol) mdr_cout_char_rep(y, x, ' ', SCHEME_TEXT, screenlastcol - x);
 
#ifdef DBG_REFRESH
    mdr_cout_char(y, 0, m, SCHEME_STBAR1);
#endif
 
    if (y == screenh - 2) break;
  }
 
  /* fill all lines below if empty (and they need to be redrawn) */
  if (l == NULL) {
    while ((y < screenlastrow) && (y < uidirty.to)) {
      mdr_cout_char_rep(y++, 0, ' ', SCHEME_TEXT, screenlastcol);
    }
  }
 
  /* scroll bar */
  for (y = 0; y < screenlastrow; y++) {
    mdr_cout_char(y, screenlastcol, SCROLL_CURSOR, SCHEME_SCROLL);
  }
 
  /* scroll cursor */
  if (db->totlines >= screenh) {
    unsigned short topline = db->curline - db->cursorposy;
    unsigned short col;
    unsigned short totlines = db->totlines - screenh + 1;
    if (db->totlines - screenh > screenh) {
      col = topline / (totlines / screenlastrow);
    } else {
      col = topline * screenlastrow / totlines;
    }
    if (col >= screenlastrow) col = screenh - 2;
    mdr_cout_char(col, screenlastcol, ' ', SCHEME_SCROLL);
  }
 
  /* clear out the dirty flag */
  uidirty.from = 0xff;
}
 
 
static void check_cursor_not_after_eol(struct file *db) {
  if (db->xoffset + db->cursorposx <= db->cursor->len) return;
 
  if (db->cursor->len < db->xoffset) {
    db->cursorposx = 0;
    db->xoffset = db->cursor->len;
    uidirty.from = 0;
    uidirty.to = 0xff;
  } else {
    db->cursorposx = db->cursor->len - db->xoffset;
  }
}
 
 
static void cursor_up(struct file *db) {
  if (db->cursor->prev == NULL) return;
 
  db->curline -= 1;
  db->cursor = db->cursor->prev;
  if (db->cursorposy == 0) {
    uidirty.from = 0;
    uidirty.to = 0xff;
  } else {
    db->cursorposy -= 1;
  }
}
 
 
static void cursor_eol(struct file *db) {
  /* adjust xoffset to make sure eol is visible on screen */
  if (db->xoffset > db->cursor->len) {
    db->xoffset = db->cursor->len - 1;
    uidirty.from = 0;
    uidirty.to = 0xff;
  }
 
  if (db->xoffset + screenlastcol <= db->cursor->len) {
    db->xoffset = db->cursor->len - screenw + 2;
    uidirty.from = 0;
    uidirty.to = 0xff;
  }
  db->cursorposx = db->cursor->len - db->xoffset;
}
 
 
static void cursor_down(struct file *db) {
  if (db->cursor->next == NULL) return;
 
  db->curline += 1;
  db->cursor = db->cursor->next;
  if (db->cursorposy < screenh - 2) {
    db->cursorposy += 1;
  } else {
    uidirty.from = 0;
    uidirty.to = 0xff;
  }
}
 
 
static void cursor_left(struct file *db) {
  if (db->cursorposx > 0) {
    db->cursorposx -= 1;
  } else if (db->xoffset > 0) {
    db->xoffset -= 1;
    uidirty.from = 0;
    uidirty.to = 0xff;
  } else if (db->cursor->prev != NULL) { /* jump to end of line above */
    cursor_up(db);
    cursor_eol(db);
  }
}
 
 
static void cursor_home(struct file *db) {
  db->cursorposx = 0;
  if (db->xoffset != 0) {
    db->xoffset = 0;
    uidirty.from = 0;
    uidirty.to = 0xff;
  }
}
 
 
static void cursor_right(struct file *db) {
  if (db->cursor->len > db->xoffset + db->cursorposx) {
    if (db->cursorposx < screenw - 2) {
      db->cursorposx += 1;
    } else {
      db->xoffset += 1;
      uidirty.from = 0;
      uidirty.to = 0xff;
    }
  } else if (db->cursor->next != NULL) { /* jump to start of next line */
    cursor_down(db);
    cursor_home(db);
  }
}
 
 
static void del(struct file *db) {
  if (db->cursorposx + db->xoffset < db->cursor->len) {
    _fmemmove(db->cursor->payload + db->cursorposx + db->xoffset, db->cursor->payload + db->cursorposx + db->xoffset + 1, db->cursor->len - db->cursorposx - db->xoffset);
    db->cursor->len -= 1; /* do this AFTER memmove so the copy includes the nul terminator */
    uidirty.from = db->cursorposy;
    uidirty.to = db->cursorposy;
    db->modflag = 1;
  } else if (db->cursor->next != NULL) { /* cursor is at end of line: merge current line with next one (if there is a next one) */
    struct line far *nextline = db->cursor->next;
    if (db->cursor->next->len > 0) {
      if (curline_resize(db, db->cursor->len + db->cursor->next->len + 1) == 0) {
        _fmemmove(db->cursor->payload + db->cursor->len, db->cursor->next->payload, db->cursor->next->len + 1);
        db->cursor->len += db->cursor->next->len;
      }
    }
 
    db->cursor->next = db->cursor->next->next;
    db->cursor->next->prev = db->cursor;
 
    line_free(nextline);
    uidirty.from = db->cursorposy;
    uidirty.to = 0xff;
    db->totlines -= 1;
    db->modflag = 1;
  }
}
 
 
static void bkspc(struct file *db) {
  /* backspace is basically "left + del", not applicable only if cursor is on 1st byte of the file */
  if ((db->cursorposx + db->xoffset == 0) && (db->cursor->prev == NULL)) return;
 
  cursor_left(db);
  del(db);
}
 
 
/* returns 0 on success, 1 on file not found, 2 on other error */
static int loadfile(struct file *db, const char *fname) {
  char buff[512]; /* read one entire sector at a time (faster) */
  char *buffptr;
  unsigned int len, llen;
  int fd;
  unsigned char eolfound;
 
  /* free the entire linked list of lines */
  db_rewind(db);
  while (db->cursor) {
    struct line far *victim;
    victim = db->cursor;
    db->cursor = db->cursor->next;
    line_free(victim);
  }
 
  /* zero out the struct */
  bzero(db, sizeof(struct file));
 
  if (fname == NULL) goto SKIPLOADING;
 
  memcpy(db->fname, fname, strlen(fname));
 
  if (_dos_open(fname, O_RDONLY, &fd) != 0) {
    return(1);
  }
 
  db->lfonly = 1;
 
  /* start by adding an empty line */
  if (line_add(db, NULL, 0) != 0) {
    /* TODO ERROR HANDLING */
  }
 
  for (eolfound = 0;;) {
    unsigned short consumedbytes;
 
    if ((_dos_read(fd, buff, sizeof(buff), &len) != 0) || (len == 0)) break;
    buffptr = buff;
 
    FINDLINE:
 
    /* look for nearest \n (also expand tabs) */
    for (consumedbytes = 0;; consumedbytes++) {
 
      if (buffptr[consumedbytes] == '\t') {
        llen = consumedbytes;
        break;
      }
 
      if (consumedbytes == len) {
        llen = consumedbytes;
        break;
      }
      if (buffptr[consumedbytes] == '\r') {
        llen = consumedbytes;
        consumedbytes++;
        db->lfonly = 0;
        break;
      }
      if (buffptr[consumedbytes] == '\n') {
        eolfound = 1;
        llen = consumedbytes;
        consumedbytes++;
        break;
      }
    }
 
    /* consumedbytes is the amount of bytes processed from buffptr,
     * llen is the length of line's payload (without its line terminator) */
 
    /* append content, if line is non-empty */
    if ((llen > 0) && (line_append(db, buffptr, llen) != 0)) {
      goto IOERR;
    }
 
    /* allocate the next line if current line ended */
    if (eolfound) {
      if (line_add(db, NULL, 0) != 0) {
        goto IOERR;
      }
      eolfound = 0;
    }
 
    /* append 8 spaces if tab char found */
    if ((consumedbytes < len) && (buffptr[consumedbytes] == '\t') && (glob_tablessmode == 0)) {
      consumedbytes++;
      if (line_append(db, "        ", 8) != 0) {
        goto IOERR;
      }
    }
 
    /* anything left? process the buffer leftover again */
    if (consumedbytes < len) {
      len -= consumedbytes;
      buffptr += consumedbytes;
      goto FINDLINE;
    }
 
  }
 
  _dos_close(fd);
 
  SKIPLOADING:
 
  /* add an empty line at end if not present already, also rewind cursor to top of file */
  if ((db->cursor == NULL) || (db->cursor->len != 0)) line_add(db, NULL, 0);
  db_rewind(db);
 
  return(0);
 
  IOERR:
  _dos_close(fd);
  return(2);
}
 
 
/* a custom argv-parsing routine that looks directly inside the PSP, avoids the need
 * of argc and argv, saves some 330 bytes of binary size
 * returns non-zero on error */
static int parseargv(struct file *dbarr) {
  char *tail = (void *)0x81; /* THIS WORKS ONLY IN SMALL MEMORY MODEL */
  unsigned short count = 0;
  char *arg;
  unsigned short lastarg = 0;
  int err;
 
  while (!lastarg) {
    /* jump to nearest arg */
    while (*tail == ' ') {
      *tail = 0;
      tail++;
    }
 
    if (*tail == '\r') {
      *tail = 0;
      break;
    }
 
    arg = tail;
 
    /* jump to next delimiter */
    while ((*tail != ' ') && (*tail != '\r')) tail++;
 
    /* if \r then remember this is the last arg */
    if (*tail == '\r') lastarg = 1;
 
    *tail = 0;
    tail++;
 
    /* look at the arg now */
    if (*arg == '/') {
      if (arg[1] == 't') { /* /t = do not expand tabs */
        glob_tablessmode = 1;
 
      } else if (arg[1] == 'm') { /* /m = force mono mode */
        glob_monomode = 1;
 
      } else {  /* help screen */
        mdr_coutraw_str(svarlang_str(1,3)); /* Sved, the SvarDOS editor */
        mdr_coutraw_str(" [");
        mdr_coutraw_str(svarlang_str(1,4)); /* ver */
        mdr_coutraw_puts(" " PVER "]");
        mdr_coutraw_puts("Copyright (C) " PDATE " Mateusz Viste");
        mdr_coutraw_crlf();
        mdr_coutraw_str("sved [/m] [/t] ");
        mdr_coutraw_puts(svarlang_str(1,1)); /* args syntax */
        mdr_coutraw_crlf();
        mdr_coutraw_puts(svarlang_str(1,10)); /* /m */
        mdr_coutraw_puts(svarlang_str(1,11)); /* /t */
        return(-1);
      }
      continue;
    }
 
    /* looks to be a filename */
    if (count == 10) {
      mdr_coutraw_puts(svarlang_str(0,12)); /* too many files */
      return(-1);
    }
 
    /* try loading it */
    mdr_coutraw_str(svarlang_str(1,2));
    mdr_coutraw_char(' ');
    mdr_coutraw_puts(arg);
    err = loadfile(&(dbarr[count]), arg);
    if (err) {
      if (err == 1) { /* file not found */
        if ((count == 0) && (lastarg != 0)) { /* a 'file not found' is fine if only one file was given */
          memcpy(dbarr[count].fname, arg, strlen(arg) + 1);
          err = 0;
        } else {
          err = 11;
        }
      } else { /* general error */
        err = 10;
      }
      if (err) {
        mdr_coutraw_puts(svarlang_str(0,err));
        return(-1);
      }
    }
    count++;
  }
 
  return(0);
}
 
 
static int savefile(const struct file *db, const char *newfname) {
  int fd;
  const struct line far *l;
  unsigned int bytes;
  unsigned char eollen;
  unsigned char eolbuf[2];
  int errflag = 0;
 
  /* either create a new file if newfname provided, or... */
  if (newfname) {
    if (_dos_creatnew(newfname, _A_NORMAL, &fd) != 0) return(-1);
  } else { /* ...open db->fname */
    if (_dos_open(db->fname, O_WRONLY, &fd) != 0) return(-1);
  }
 
  l = db->cursor;
  while (l->prev) l = l->prev;
 
  /* preset line terminators */
  if (db->lfonly) {
    eolbuf[0] = '\n';
    eollen = 1;
  } else {
    eolbuf[0] = '\r';
    eolbuf[1] = '\n';
    eollen = 2;
  }
 
  while (l) {
    /* do not write the last empty line, it is only useful for edition */
    if (l->len != 0) {
      errflag |= _dos_write(fd, l->payload, l->len, &bytes);
    } else if (l->next == NULL) {
      break;
    }
    errflag |= _dos_write(fd, eolbuf, eollen, &bytes);
    l = l->next;
  }
 
  errflag |= _dos_close(fd);
 
  return(errflag);
}
 
 
static void insert_in_line(struct file *db, const char *databuf, unsigned short len) {
  if (curline_resize(db, db->cursor->len + len) == 0) {
    unsigned short off = db->xoffset + db->cursorposx;
    db->modflag = 1;
    _fmemmove(db->cursor->payload + off + len, db->cursor->payload + off, db->cursor->len - off + 1);
    db->cursor->len += len;
    uidirty.from = db->cursorposy;
    uidirty.to = db->cursorposy;
    while (len--) {
      db->cursor->payload[off++] = *databuf;
      databuf++;
      cursor_right(db);
    }
  }
}
 
 
/* recompute db->curline by counting nodes in linked list */
static void recompute_curline(struct file *db) {
  const struct line far *l = db->cursor;
 
  db->curline = 0;
  while (l->prev != NULL) {
    db->curline += 1;
    l = l->prev;
  }
}
 
 
enum MENU_ACTION {
  MENU_NONE   = 0,
  MENU_OPEN   = 1,
  MENU_SAVE   = 2,
  MENU_SAVEAS = 3,
  MENU_CLOSE  = 4,
  MENU_CHGEOL = 5,
  MENU_QUIT   = 6
};
 
static enum MENU_ACTION ui_menu(void) {
  unsigned short i, curchoice, attr, x, slen;
  unsigned short xorigin, yorigin;
 
  /* find out the longest string */
  slen = 0;
  for (i = MENU_OPEN; i <= MENU_QUIT; i++) {
    x = strlen(svarlang_str(8, i));
    if (x > slen) slen = x;
  }
 
  /* calculate where to draw the menu on screen */
  xorigin = (screenw - (slen + 5)) / 2;
  yorigin = (screenh - (MENU_QUIT - MENU_OPEN + 6)) / 2;
 
  /* */
  uidirty.from = yorigin;
  uidirty.to = 0xff;
  uidirty.statusbar = 1;
 
  /* hide the cursor */
  mdr_cout_cursor_hide();
 
  curchoice = MENU_OPEN;
  for (;;) {
    /* render menu */
    for (i = MENU_NONE; i <= MENU_QUIT + 1; i++) {
      mdr_cout_char_rep(yorigin + i, xorigin, ' ', SCHEME_MENU, slen+4);
      if (i == curchoice) {
        attr = SCHEME_MENU_CUR;
        mdr_cout_char_rep(yorigin + i, xorigin + 1, ' ', SCHEME_MENU_SEL, slen + 2);
      } else {
        attr = SCHEME_MENU;
      }
      mdr_cout_str(yorigin + i, xorigin + 2, svarlang_str(8, i), attr, slen);
    }
    /* wait for key */
    switch (mdr_dos_getkey2()) {
      case 0x150: /* down */
        if (curchoice == MENU_QUIT) {
          curchoice = MENU_OPEN;
        } else {
          curchoice++;
        }
        break;
      case 0x148: /* up */
        if (curchoice == MENU_OPEN) {
          curchoice = MENU_QUIT;
        } else {
          curchoice--;
        }
        break;
      default:
        curchoice = MENU_NONE;
        /* FALLTHRU */
      case '\r': /* ENTER */
        mdr_cout_cursor_show();
        return(curchoice);
    }
  }
}
 
 
static struct file *select_slot(struct file *dbarr, unsigned char curfile) {
  uidirty.from = 0;
  uidirty.to = 0xff;
  uidirty.statusbar = 1;
 
  dbarr = &(dbarr[curfile]);
  /* force redraw now, because the main() routine might not if this is exit
   * time and we want to show the user which file has unsaved changes */
  ui_statusbar(dbarr, curfile);
  ui_refresh(dbarr);
  return(dbarr);
}
 
 
/* main returns nothing, ie. sved always exits with a zero exit code
 * (this saves 20 bytes of executable footprint) */
void main(void) {
  static struct file dbarr[10];
  unsigned char curfile;
  struct file *db = dbarr; /* visible file is the first slot by default */
  struct line far *clipboard = NULL;
  unsigned char original_breakflag;
 
  { /* load NLS resource */
    unsigned short i = 0;
    const char far *selfptr;
    char self[128], lang[8];
    selfptr = mdr_dos_selfexe();
    if (selfptr != NULL) {
      do {
        self[i] = selfptr[i];
      } while (self[i++] != 0);
      svarlang_autoload_exepath(self, mdr_dos_getenv(lang, "LANG", sizeof(lang)));
    }
  }
 
  /* preload all slots with empty files */
  for (curfile = 9;; curfile--) {
    loadfile(&(dbarr[curfile]), NULL);
    if (curfile == 0) break;
  }
 
  /* parse argv (and load files, if any passed on) */
  if (parseargv(dbarr) != 0) return;
 
  if ((mdr_cout_init(&screenw, &screenh) != 0) && (glob_monomode == 0)) {
    /* load color scheme if mdr_cout_init returns a color flag */
    SCHEME_TEXT = 0x17;
    SCHEME_MENU = 0x70;
    SCHEME_MENU_CUR = 0x6f;
    SCHEME_MENU_SEL = 0x66;
    SCHEME_STBAR1 = 0x70;
    SCHEME_STBAR2 = 0x78;
    SCHEME_STBAR3 = 0x3f;
    SCHEME_SCROLL = 0x70;
    SCHEME_MSG = 0x6f;
    SCHEME_ERR = 0x4f;
  }
  screenlastrow = screenh - 1;
  screenlastcol = screenw - 1;
 
  /* instruct DOS to stop detecting CTRL+C because user needs it for
   * copy/paste operations. also remember the original status of the BREAK
   * flag so I can restore it as it was before quitting. */
  original_breakflag = mdr_dos_ctrlc_disable();
 
  for (;;) {
    int k;
 
    /* add an extra empty line if cursor is on last line and this line is not empty */
    if ((db->cursor->next == NULL) && (db->cursor->len != 0)) {
      if (line_add(db, NULL, 0) == 0) {
        db->cursor = db->cursor->prev; /* line_add() changes the cursor pointer */
        db->curline -= 1;
      }
    }
 
    check_cursor_not_after_eol(db);
    mdr_cout_locate(db->cursorposy, db->cursorposx);
 
    ui_refresh(db);
 
    if ((uidirty.statusbar != 0) || (db->modflagprev != db->modflag) || (db->curline_prev != db->curline)) {
      ui_statusbar(db, curfile);
      uidirty.statusbar = 0;
      db->modflagprev = db->modflag;
      db->curline_prev = db->curline;
    }
#ifdef DBG_LINENUM
      {
        char ddd[10];
        db->curline += 1;
        ddd[0] = '0' + db->curline / 100;
        ddd[1] = '0' + (db->curline % 100) / 10;
        ddd[2] = '0' + (db->curline % 10);
        db->curline -= 1;
        ddd[3] = '/';
        ddd[4] = '0' + db->totlines / 100;
        ddd[5] = '0' + (db->totlines % 100) / 10;
        ddd[6] = '0' + (db->totlines % 10);
        ddd[7] = 0;
        mdr_cout_str(screenh - 1, 40, ddd, SCHEME_STBAR1, sizeof(ddd));
      }
#endif
 
    k = mdr_dos_getkey2();
 
    if (k == 0x150) { /* down */
      cursor_down(db);
 
    } else if (k == 0x148) { /* up */
      cursor_up(db);
 
    } else if (k == 0x14D) { /* right */
      cursor_right(db);
 
    } else if (k == 0x14B) { /* left */
      cursor_left(db);
 
    } else if (k == 0x149) { /* pgup */
      unsigned char dist = db->cursorposy + screenh - 1;
      while ((dist != 0) && (db->cursor->prev != NULL)) {
        db->cursor = db->cursor->prev;
        dist--;
      }
      if (dist != 0) {
        db->cursorposy = 0;
        db->cursorposx = 0;
      } else {
        dist = db->cursorposy;
        while ((dist--) && (db->cursor->next)) db->cursor = db->cursor->next;
      }
      uidirty.from = 0;
      uidirty.to = 0xff;
      recompute_curline(db);
 
    } else if (k == 0x151) { /* pgdown */
      unsigned char dist = screenh + screenh - db->cursorposy - 3;
      while ((dist != 0) && (db->cursor->next != NULL)) {
        db->cursor = db->cursor->next;
        dist--;
      }
      if (dist != 0) {
        db->cursorposy = screenh - 2;
        if (db->totlines <= db->cursorposy) db->cursorposy = db->totlines - 1;
        db->cursorposx = 0;
      } else {
        dist = screenh - 2 - db->cursorposy;
        while ((dist--) && (db->cursor->prev)) db->cursor = db->cursor->prev;
      }
      uidirty.from = 0;
      uidirty.to = 0xff;
      recompute_curline(db);
 
    } else if (k == 0x147) { /* home */
       cursor_home(db);
 
    } else if (k == 0x14F) { /* end */
       cursor_eol(db);
 
    } else if (k == 0x1B) { /* ESC */
      int quitnow = 0;
      char fname[64];
      int saveflag = 0;
      enum MENU_ACTION ui_action;
 
      /* collect the exact menu action and clear the screen */
      ui_action = ui_menu();
      ui_refresh(db);
 
      switch (ui_action) {
 
        case MENU_NONE:
          break;
 
        case MENU_OPEN:
          /* display a warning if unsaved changes are pending */
          if (db->modflag != 0) ui_msg(svarlang_str(0,4), svarlang_str(0,8), SCHEME_MSG);
 
          /* ask for filename */
          ui_getstring(svarlang_str(0,7), fname, sizeof(fname));
          if (fname[0] != 0) {
            int err;
            err = loadfile(db, fname);
            if (err != 0) {
              if (err == 1) {
                ui_msg(svarlang_str(0,11), NULL, SCHEME_ERR); /* file not found */
              } else {
                ui_msg(svarlang_str(0,10), NULL, SCHEME_ERR);  /* ERROR */
              }
              mdr_bios_tickswait(44); /* 3s */
              loadfile(db, NULL);
            }
          }
          uidirty.from = 0;
          uidirty.to = 0xff;
          uidirty.statusbar = 1;
          break;
 
        case MENU_SAVEAS:
          saveflag = 1;
          /* FALLTHRU */
        case MENU_SAVE:
          if ((saveflag != 0) || (db->fname[0] == 0)) { /* save as... */
            ui_getstring(svarlang_str(0,6), fname, sizeof(fname));
            if (*fname == 0) break;
            saveflag = savefile(db, fname);
            if (saveflag == 0) memcpy(db->fname, fname, sizeof(fname));
          } else {
            saveflag = savefile(db, NULL);
          }
 
          mdr_cout_cursor_hide();
 
          if (saveflag == 0) {
            db->modflag = 0;
            ui_msg(svarlang_str(0, 2), NULL, SCHEME_MSG);
            mdr_bios_tickswait(11); /* 11 ticks is about 600 ms */
          } else {
            ui_msg(svarlang_str(0, 10), NULL, SCHEME_ERR);
            mdr_bios_tickswait(36); /* 2s */
          }
          mdr_cout_cursor_show();
          break;
 
        case MENU_CLOSE:
          if (ui_confirm_if_unsaved(db) == 0) {
            loadfile(db, NULL);
          }
          uidirty.from = 0;
          uidirty.to = 0xff;
          uidirty.statusbar = 1;
          break;
 
        case MENU_CHGEOL:
          db->modflag = 1;
          db->lfonly ^= 1;
          break;
 
        case MENU_QUIT:
          quitnow = 1;
          for (curfile = 0; curfile < 10; curfile++) {
            if (dbarr[curfile].modflag) {
              db = select_slot(dbarr, curfile);
              if (ui_confirm_if_unsaved(db) != 0) quitnow = 0;
            }
          }
          break;
      }
 
      if (quitnow) break;
 
    } else if (k == 0x0D) { /* ENTER */
      unsigned short off = db->xoffset + db->cursorposx;
      /* add a new line */
      if (line_add(db, db->cursor->payload + off, db->cursor->len - off) == 0) {
        db->modflag = 1;
        db->cursor = db->cursor->prev; /* back to original line */
        db->curline -= 1;
        /* trim the line above */
        db->cursor->len = off;
        /* move cursor to the (new) line below */
        uidirty.from = db->cursorposy;
        uidirty.to = 0xff;
        cursor_down(db);
        cursor_home(db);
      } else {
        /* ERROR: OUT OF MEMORY */
      }
 
    } else if (k == 0x153) {  /* DEL */
      del(db);
 
    } else if (k == 0x008) { /* BKSPC */
      bkspc(db);
 
    } else if ((k >= 0x20) && (k <= 0xff)) { /* "normal" character */
      char c = k;
      insert_in_line(db, &c, 1);
 
    } else if (k == 0x009) { /* TAB */
      if (glob_tablessmode == 0) {
        insert_in_line(db, "        ", 8);
      } else {
        insert_in_line(db, "\t", 1);
      }
 
    } else if ((k >= 0x13b) && (k <= 0x144)) { /* F1..F10 */
      curfile = k - 0x13b;
      db = select_slot(dbarr, curfile);
 
    } else if (k == 0x174) { /* CTRL+ArrRight - jump to next word */
      /* if currently cursor is on a non-space, then fast-forward to nearest space or EOL */
      for (;;) {
        if (db->xoffset + db->cursorposx == db->cursor->len) break;
        if (db->cursor->payload[db->xoffset + db->cursorposx] == ' ') break;
        cursor_right(db);
      }
      /* now skip to next non-space or end of file */
      for (;;) {
        cursor_right(db);
        if (db->cursor->payload[db->xoffset + db->cursorposx] != ' ') break;
        if ((db->cursor->next == NULL) && (db->cursorposx + db->xoffset == db->cursor->len)) break;
      }
 
    } else if (k == 0x173) { /* CTRL+ArrLeft - jump to prev word */
      cursor_left(db);
      /* if currently cursor is on a space, then fast-forward to nearest non-space or start of line */
      for (;;) {
        if ((db->xoffset == 0) && (db->cursorposx == 0)) break;
        if (db->cursor->payload[db->xoffset + db->cursorposx] != ' ') break;
        cursor_left(db);
      }
      /* now skip to next space or start of file */
      for (;;) {
        cursor_left(db);
        if (db->cursor->payload[db->xoffset + db->cursorposx] == ' ') {
          cursor_right(db);
          break;
        }
        if ((db->cursorposx == 0) && (db->xoffset == 0)) break;
      }
 
    } else if ((k == 0x003) || (k == 0x018)) { /* CTRL+C or CTRL+X */
      /* free clipboard if anything in it */
      if (clipboard != NULL) line_free(clipboard);
 
      /* copy cursor line to clipboard */
      clipboard = line_calloc(db->cursor->len);
      if (clipboard == NULL) {
        ui_msg(svarlang_str(0, 10), NULL, SCHEME_ERR); /* ERROR */
        mdr_bios_tickswait(18); /* 1s */
      } else {
        mdr_cout_char_rep(db->cursorposy, 0, ' ', ((SCHEME_TEXT >> 4) | (SCHEME_TEXT << 4)) & 0xff, screenlastcol);
        uidirty.from = db->cursorposy;
        uidirty.to = db->cursorposy;
        if (db->cursor->len != 0) {
          _fmemmove(clipboard->payload, db->cursor->payload, db->cursor->len);
          clipboard->len = db->cursor->len;
        }
        mdr_bios_tickswait(2); /* ca 100ms */
 
        /* if this is about cutting the line (CTRL+X) then delete cur line */
        if ((k == 0x018) && ((db->cursor->next != NULL) || (db->cursor->prev != NULL))) {
          if (db->cursor->next) db->cursor->next->prev = db->cursor->prev;
          if (db->cursor->prev) db->cursor->prev->next = db->cursor->next;
          clipboard->prev = db->cursor;
          if (db->cursor->next) {
            db->cursor = db->cursor->next;
          } else {
            cursor_up(db);
          }
          line_free(clipboard->prev);
          db->totlines -= 1;
          uidirty.from = 0;
          uidirty.to = 0xff;
          recompute_curline(db);
        }
      }
 
    } else if ((k == 0x016) && (clipboard != NULL)) { /* CTRL+V */
      if (line_add(db, clipboard->payload, clipboard->len) != 0) {
        ui_msg(svarlang_str(0, 10), NULL, SCHEME_ERR); /* ERROR */
        mdr_bios_tickswait(18); /* 1s */
      } else {
        /* rewire the linked list so the new line is on top of the previous one */
        clipboard->prev = db->cursor->prev;
        /* remove prev node from list */
        db->cursor->prev = db->cursor->prev->prev;
        if (db->cursor->prev != NULL) db->cursor->prev->next = db->cursor;
        /* insert the node after cursor now */
        clipboard->prev->next = db->cursor->next;
        if (db->cursor->next != NULL) db->cursor->next->prev = clipboard->prev;
        clipboard->prev->prev = db->cursor;
        db->cursor->next = clipboard->prev;
        cursor_down(db);
      }
      uidirty.from = 0;
      uidirty.to = 0xff;
      recompute_curline(db);
 
#ifdef DBG_UNHKEYS
    } else { /* UNHANDLED KEY - TODO IGNORE THIS IN PRODUCTION RELEASE */
      char buff[4];
      const char *HEX = "0123456789ABCDEF";
      buff[0] = HEX[(k >> 8) & 15];
      buff[1] = HEX[(k >> 4) & 15];
      buff[2] = HEX[k & 15];
      mdr_cout_str(screenh - 1, 0, "UNHANDLED KEY: 0x", SCHEME_STBAR1, 17);
      mdr_cout_str(screenh - 1, 17, buff, SCHEME_STBAR1, 3);
      mdr_dos_getkey2();
      break;
#endif
    }
  }
 
  mdr_cout_close();
 
  /* restore the DOS BREAK flag if it was originally set */
  if (original_breakflag != 0) mdr_dos_ctrlc_enable();
 
  /* no need to free memory, DOS will do it for me */
 
  return;
}
 

Rev 1438	Rev 1439
1	`/* Sved, the SvarDOS editor`	1	`/* Sved, the SvarDOS editor`
2	`*`	2	`*`
3	`* Copyright (C) 2023 Mateusz Viste`	3	`* Copyright (C) 2023 Mateusz Viste`
4	`*`	4	`*`
5	`* Sved is released under the terms of the MIT license.`	5	`* Sved is released under the terms of the MIT license.`
6	`*`	6	`*`
7	`* Permission is hereby granted, free of charge, to any person obtaining a copy`	7	`* Permission is hereby granted, free of charge, to any person obtaining a copy`
8	`* of this software and associated documentation files (the "Software"), to`	8	`* of this software and associated documentation files (the "Software"), to`
9	`* deal in the Software without restriction, including without limitation the`	9	`* deal in the Software without restriction, including without limitation the`
10	`* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or`	10	`* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or`
11	`* sell copies of the Software, and to permit persons to whom the Software is`	11	`* sell copies of the Software, and to permit persons to whom the Software is`
12	`* furnished to do so, subject to the following conditions:`	12	`* furnished to do so, subject to the following conditions:`
13	`*`	13	`*`
14	`* The above copyright notice and this permission notice shall be included in`	14	`* The above copyright notice and this permission notice shall be included in`
15	`* all copies or substantial portions of the Software.`	15	`* all copies or substantial portions of the Software.`
16	`*`	16	`*`
17	`* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR`	17	`* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR`
18	`* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,`	18	`* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,`
19	`* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE`	19	`* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE`
20	`* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER`	20	`* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER`
21	`* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING`	21	`* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING`
22	`* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS`	22	`* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS`
23	`* IN THE SOFTWARE.`	23	`* IN THE SOFTWARE.`
24	`*/`	24	`*/`
25		25
26	`#include <dos.h> /* _dos_open(), _dos_read(), _dos_close(), ... */`	26	`#include <dos.h> /* _dos_open(), _dos_read(), _dos_close(), ... */`
27	`#include <fcntl.h> /* O_RDONLY, O_WRONLY */`	27	`#include <fcntl.h> /* O_RDONLY, O_WRONLY */`
28	`#include <string.h>`	28	`#include <string.h>`
29		29
30	`#include "mdr\bios.h"`	30	`#include "mdr\bios.h"`
31	`#include "mdr\cout.h"`	31	`#include "mdr\cout.h"`
32	`#include "mdr\dos.h"`	32	`#include "mdr\dos.h"`
33		33
34	`#include "svarlang\svarlang.h"`	34	`#include "svarlang\svarlang.h"`
35		35
36		36
37	`#define PVER "2023.0"`	37	`#define PVER "2023.0"`
38	`#define PDATE "2023"`	38	`#define PDATE "2023"`
39		39
40	`/*****************************************************************************`	40	`/*****************************************************************************`
41	`* global variables and definitions *`	41	`* global variables and definitions *`
42	`*****************************************************************************/`	42	`*****************************************************************************/`
43		43
44	`/* preload the mono scheme (to be overloaded at runtime if color adapter present) */`	44	`/* preload the mono scheme (to be overloaded at runtime if color adapter present) */`
45	`static unsigned char SCHEME_TEXT = 0x07,`	45	`static unsigned char SCHEME_TEXT = 0x07,`
46	`SCHEME_MENU = 0x70,`	46	`SCHEME_MENU = 0x70,`
47	`SCHEME_MENU_CUR= 0x0f,`	47	`SCHEME_MENU_CUR= 0x0f,`
48	`SCHEME_MENU_SEL= 0x00,`	48	`SCHEME_MENU_SEL= 0x00,`
49	`SCHEME_STBAR1 = 0x70,`	49	`SCHEME_STBAR1 = 0x70,`
50	`SCHEME_STBAR2 = 0x70, /* greyed out information */`	50	`SCHEME_STBAR2 = 0x70, /* greyed out information */`
51	`SCHEME_STBAR3 = 0x70, /* query */`	51	`SCHEME_STBAR3 = 0x70, /* query */`
52	`SCHEME_SCROLL = 0x70,`	52	`SCHEME_SCROLL = 0x70,`
53	`SCHEME_MSG = 0x70,`	53	`SCHEME_MSG = 0x70,`
54	`SCHEME_ERR = 0x70;`	54	`SCHEME_ERR = 0x70;`
55		55
56	`static unsigned char screenw, screenh, screenlastrow, screenlastcol;`	56	`static unsigned char screenw, screenh, screenlastrow, screenlastcol;`
57	`static unsigned char glob_monomode, glob_tablessmode;`	57	`static unsigned char glob_monomode, glob_tablessmode;`
58		58
59	`static struct {`	59	`static struct {`
60	`unsigned char from;`	60	`unsigned char from;`
61	`unsigned char to;`	61	`unsigned char to;`
62	`unsigned char statusbar;`	62	`unsigned char statusbar;`
63	`} uidirty = {0, 0xff, 1}; /* make sure to redraw entire UI at first run */`	63	`} uidirty = {0, 0xff, 1}; /* make sure to redraw entire UI at first run */`
64		64
65	`#define SCROLL_CURSOR 0xB1`	65	`#define SCROLL_CURSOR 0xB1`
66		66
67	`struct line {`	67	`struct line {`
68	`unsigned short len;`	68	`unsigned short len;`
69	`struct line far *next;`	69	`struct line far *next;`
70	`struct line far *prev;`	70	`struct line far *prev;`
71	`char payload[1];`	71	`char payload[1];`
72	`};`	72	`};`
73		73
74	`struct file {`	74	`struct file {`
75	`struct line far *cursor;`	75	`struct line far *cursor;`
76	`unsigned short xoffset;`	76	`unsigned short xoffset;`
77	`unsigned short cursorposx;`	77	`unsigned short cursorposx;`
78	`unsigned short cursorposy;`	78	`unsigned short cursorposy;`
79	`unsigned short totlines;`	79	`unsigned short totlines;`
80	`unsigned short curline;`	80	`unsigned short curline;`
81	`unsigned short curline_prev;`	81	`unsigned short curline_prev;`
82	`char lfonly; /* set if line endings are LF (CR/LF otherwise) */`	82	`char lfonly; /* set if line endings are LF (CR/LF otherwise) */`
83	`char modflag; /* non-zero if file has been modified since last save */`	83	`char modflag; /* non-zero if file has been modified since last save */`
84	`char modflagprev;`	84	`char modflagprev;`
85	`char fname[128];`	85	`char fname[128];`
86	`};`	86	`};`
87		87
88		88
89	`/*****************************************************************************`	89	`/*****************************************************************************`
90	`* functions *`	90	`* functions *`
91	`*****************************************************************************/`	91	`*****************************************************************************/`
92		92
93	`static struct line far *line_calloc(unsigned short siz) {`	93	`static struct line far *line_calloc(unsigned short siz) {`
94	`struct line far *res;`	94	`struct line far *res;`
95	`unsigned int seg;`	95	`unsigned int seg;`
96	`if (_dos_allocmem((sizeof(struct line) + siz + 15) / 16, &seg) != 0) return(NULL);`	96	`if (_dos_allocmem((sizeof(struct line) + siz + 15) / 16, &seg) != 0) return(NULL);`
97	`res = MK_FP(seg, 0);`	97	`res = MK_FP(seg, 0);`
98	`_fmemset(res, 0, sizeof(struct line) + siz);`	98	`_fmemset(res, 0, sizeof(struct line) + siz);`
99	`return(MK_FP(seg, 0));`	99	`return(MK_FP(seg, 0));`
100	`}`	100	`}`
101		101
102		102
103	`static void line_free(struct line far *ptr) {`	103	`static void line_free(struct line far *ptr) {`
104	`_dos_freemem(FP_SEG(ptr));`	104	`_dos_freemem(FP_SEG(ptr));`
105	`}`	105	`}`
106		106
107		107
108	`static int curline_resize(struct file far *db, unsigned short newsiz) {`	108	`static int curline_resize(struct file far *db, unsigned short newsiz) {`
109	`unsigned int maxavail;`	109	`unsigned int maxavail;`
110	`struct line far *newptr;`	110	`struct line far *newptr;`
111		111
112	`/* try resizing the block (much faster) */`	112	`/* try resizing the block (much faster) */`
113	`if (_dos_setblock((sizeof(struct line) + newsiz + 15) / 16, FP_SEG(db->cursor), &maxavail) == 0) return(0);`	113	`if (_dos_setblock((sizeof(struct line) + newsiz + 15) / 16, FP_SEG(db->cursor), &maxavail) == 0) return(0);`
114		114
115	`/* create a new block and copy data over */`	115	`/* create a new block and copy data over */`
116	`newptr = line_calloc(newsiz);`	116	`newptr = line_calloc(newsiz);`
117	`if (newptr == NULL) return(-1);`	117	`if (newptr == NULL) return(-1);`
118	`_fmemmove(newptr, db->cursor, sizeof(struct line) + db->cursor->len);`	118	`_fmemmove(newptr, db->cursor, sizeof(struct line) + db->cursor->len);`
119		119
120	`/* rewire the linked list */`	120	`/* rewire the linked list */`
121	`db->cursor = newptr;`	121	`db->cursor = newptr;`
122	`if (newptr->next) newptr->next->prev = newptr;`	122	`if (newptr->next) newptr->next->prev = newptr;`
123	`if (newptr->prev) newptr->prev->next = newptr;`	123	`if (newptr->prev) newptr->prev->next = newptr;`
124		124
125	`return(0);`	125	`return(0);`
126	`}`	126	`}`
127		127
128		128
129	`/* adds a new line at cursor position into file linked list and advance cursor`	129	`/* adds a new line at cursor position into file linked list and advance cursor`
130	`* returns non-zero on error */`	130	`* returns non-zero on error */`
131	`static int line_add(struct file db, const char far line, unsigned short slen) {`	131	`static int line_add(struct file db, const char far line, unsigned short slen) {`
132	`struct line far *l;`	132	`struct line far *l;`
133		133
134	`l = line_calloc(slen);`	134	`l = line_calloc(slen);`
135	`if (l == NULL) return(-1);`	135	`if (l == NULL) return(-1);`
136		136
137	`l->prev = db->cursor;`	137	`l->prev = db->cursor;`
138	`if (db->cursor) {`	138	`if (db->cursor) {`
139	`l->next = db->cursor->next;`	139	`l->next = db->cursor->next;`
140	`db->cursor->next = l;`	140	`db->cursor->next = l;`
141	`l->next->prev = l;`	141	`l->next->prev = l;`
142	`}`	142	`}`
143	`db->cursor = l;`	143	`db->cursor = l;`
144	`if (slen > 0) {`	144	`if (slen > 0) {`
145	`_fmemmove(l->payload, line, slen);`	145	`_fmemmove(l->payload, line, slen);`
146	`l->len = slen;`	146	`l->len = slen;`
147	`}`	147	`}`
148		148
149	`db->totlines += 1;`	149	`db->totlines += 1;`
150	`db->curline += 1;`	150	`db->curline += 1;`
151		151
152	`return(0);`	152	`return(0);`
153	`}`	153	`}`
154		154
155		155
156	`static void ui_getstring(const char query, char s, unsigned short maxlen) {`	156	`static void ui_getstring(const char query, char s, unsigned short maxlen) {`
157	`unsigned short len = 0;`	157	`unsigned short len = 0;`
158	`unsigned char y, x;`	158	`unsigned char y, x;`
159	`int k;`	159	`int k;`
160		160
161	`if (maxlen == 0) return;`	161	`if (maxlen == 0) return;`
162	`maxlen--; /* make room for the nul terminator */`	162	`maxlen--; /* make room for the nul terminator */`
163		163
164	`y = screenlastrow;`	164	`y = screenlastrow;`
165		165
166	`/* print query string */`	166	`/* print query string */`
167	`x = mdr_cout_str(y, 0, query, SCHEME_STBAR3, 40);`	167	`x = mdr_cout_str(y, 0, query, SCHEME_STBAR3, 40);`
168	`mdr_cout_char_rep(y, x++, ' ', SCHEME_STBAR3, screenw - x);`	168	`mdr_cout_char_rep(y, x++, ' ', SCHEME_STBAR3, screenw - x);`
169		169
170	`for (;;) {`	170	`for (;;) {`
171	`mdr_cout_locate(y, x + len);`	171	`mdr_cout_locate(y, x + len);`
172	`k = mdr_dos_getkey2();`	172	`k = mdr_dos_getkey2();`
173		173
174	`switch (k) {`	174	`switch (k) {`
175	`case 0x1b: /* ESC */`	175	`case 0x1b: /* ESC */`
176	`s[0] = 0;`	176	`s[0] = 0;`
177	`return;`	177	`return;`
178	`case '\r':`	178	`case '\r':`
179	`s[len] = 0;`	179	`s[len] = 0;`
180	`return;`	180	`return;`
181	`case 0x08: /* BKSPC */`	181	`case 0x08: /* BKSPC */`
182	`if (len > 0) {`	182	`if (len > 0) {`
183	`len--;`	183	`len--;`
184	`mdr_cout_char(y, x + len, ' ', SCHEME_STBAR3);`	184	`mdr_cout_char(y, x + len, ' ', SCHEME_STBAR3);`
185	`}`	185	`}`
186	`break;`	186	`break;`
187	`default:`	187	`default:`
188	`if ((k <= 0xff) && (k >= ' ') && (len < maxlen)) {`	188	`if ((k <= 0xff) && (k >= ' ') && (len < maxlen)) {`
189	`mdr_cout_char(y, x + len, k, SCHEME_STBAR3);`	189	`mdr_cout_char(y, x + len, k, SCHEME_STBAR3);`
190	`s[len++] = k;`	190	`s[len++] = k;`
191	`}`	191	`}`
192	`}`	192	`}`
193	`}`	193	`}`
194		194
195	`}`	195	`}`
196		196
197		197
198	`/* append a nul-terminated string to line at cursor position */`	198	`/* append a nul-terminated string to line at cursor position */`
199	`static int line_append(struct file f, const char far buf, unsigned short len) {`	199	`static int line_append(struct file f, const char far buf, unsigned short len) {`
200	`if (sizeof(struct line) + f->cursor->len + len < len) goto ERR; /* overflow check */`	200	`if (sizeof(struct line) + f->cursor->len + len < len) goto ERR; /* overflow check */`
201	`if (curline_resize(f, f->cursor->len + len) != 0) goto ERR;`	201	`if (curline_resize(f, f->cursor->len + len) != 0) goto ERR;`
202		202
203	`_fmemmove(f->cursor->payload + f->cursor->len, buf, len);`	203	`_fmemmove(f->cursor->payload + f->cursor->len, buf, len);`
204	`f->cursor->len += len;`	204	`f->cursor->len += len;`
205		205
206	`return(0);`	206	`return(0);`
207	`ERR:`	207	`ERR:`
208	`return(-1);`	208	`return(-1);`
209	`}`	209	`}`
210		210
211		211
212	`static void db_rewind(struct file *db) {`	212	`static void db_rewind(struct file *db) {`
213	`if (db->cursor == NULL) return;`	213	`if (db->cursor == NULL) return;`
214	`while (db->cursor->prev) db->cursor = db->cursor->prev;`	214	`while (db->cursor->prev) db->cursor = db->cursor->prev;`
215	`db->curline = 0;`	215	`db->curline = 0;`
216	`}`	216	`}`
217		217
218		218
219	`static void ui_statusbar(const struct file *db, unsigned char slotnum) {`	219	`static void ui_statusbar(const struct file *db, unsigned char slotnum) {`
220	`const char s = svarlang_strid(0); / ESC=MENU */`	220	`const char s = svarlang_strid(0); / ESC=MENU */`
221	`unsigned short helpcol = screenw - strlen(s);`	221	`unsigned short helpcol = screenw - strlen(s);`
222	`unsigned short maxfnlen = helpcol - 14;`	222	`unsigned short maxfnlen = helpcol - 14;`
223		223
224	`/* slot number (guaranteed to be 0-9) */`	224	`/* slot number (guaranteed to be 0-9) */`
225	`{`	225	`{`
226	`char slot[4] = "#00";`	226	`char slot[4] = "#00";`
227	`if (slotnum == 9) {`	227	`if (slotnum == 9) {`
228	`slot[1] = '1';`	228	`slot[1] = '1';`
229	`} else {`	229	`} else {`
230	`slotnum++;`	230	`slotnum++;`
231	`slot[2] += slotnum;`	231	`slot[2] += slotnum;`
232	`}`	232	`}`
233	`mdr_cout_str(screenlastrow, 0, slot, SCHEME_STBAR2, 3);`	233	`mdr_cout_str(screenlastrow, 0, slot, SCHEME_STBAR2, 3);`
234	`}`	234	`}`
235		235
236	`/* fill rest of status bar with background */`	236	`/* fill rest of status bar with background */`
237	`mdr_cout_char_rep(screenlastrow, 3, ' ', SCHEME_STBAR1, helpcol - 3);`	237	`mdr_cout_char_rep(screenlastrow, 3, ' ', SCHEME_STBAR1, helpcol - 3);`
238		238
239	`/* filename and modflag */`	239	`/* filename and modflag */`
240	`{`	240	`{`
241	`const char *fn;`	241	`const char *fn;`
242	`unsigned short x;`	242	`unsigned short x;`
243	`if (db->fname[0] == 0) {`	243	`if (db->fname[0] == 0) {`
244	`fn = svarlang_str(0, 1); /* "UNTITLED" */`	244	`fn = svarlang_str(0, 1); /* "UNTITLED" */`
245	`} else {`	245	`} else {`
246	`/* display filename up to maxfnlen chars */`	246	`/* display filename up to maxfnlen chars */`
247	`fn = db->fname;`	247	`fn = db->fname;`
248	`x = strlen(fn);`	248	`x = strlen(fn);`
249	`if (x > maxfnlen) fn += x - maxfnlen;`	249	`if (x > maxfnlen) fn += x - maxfnlen;`
250	`}`	250	`}`
251	`x = mdr_cout_str(screenlastrow, 4, fn, SCHEME_STBAR1, maxfnlen);`	251	`x = mdr_cout_str(screenlastrow, 4, fn, SCHEME_STBAR1, maxfnlen);`
252	`if (db->modflag) mdr_cout_char(screenlastrow, 5 + x, '!', SCHEME_STBAR2);`	252	`if (db->modflag) mdr_cout_char(screenlastrow, 5 + x, '!', SCHEME_STBAR2);`
253	`}`	253	`}`
254		254
255	`/* eol type */`	255	`/* eol type */`
256	`{`	256	`{`
257	`const char *eoltype = "CRLF";`	257	`const char *eoltype = "CRLF";`
258	`if (db->lfonly) eoltype += 2;`	258	`if (db->lfonly) eoltype += 2;`
259	`mdr_cout_str(screenlastrow, helpcol - 6, eoltype, SCHEME_STBAR1, 5);`	259	`mdr_cout_str(screenlastrow, helpcol - 6, eoltype, SCHEME_STBAR1, 5);`
260	`}`	260	`}`
261		261
262	`/* line numbers */`	262	`/* line numbers */`
263	`{`	263	`{`
264	`unsigned short x;`	264	`unsigned short x;`
265	`unsigned char count = 0;`	265	`unsigned char count = 0;`
266	`unsigned short coloffset = 9;`	266	`unsigned short col = helpcol - 9;`
267		267
268	`x = 1 + db->totlines;`	268	`x = db->totlines;`
269	`AGAIN:`	269	`AGAIN:`
270	`do {`	270	`do {`
271	`mdr_cout_char(screenlastrow, helpcol - coloffset, '0' + (x % 10), SCHEME_STBAR1);`	271	`mdr_cout_char(screenlastrow, col--, '0' + (x % 10), SCHEME_STBAR1);`
272	`x /= 10;`	272	`x /= 10;`
273	`coloffset++;`	-
274	`} while (x);`	273	`} while (x);`
275	`/* redo same exercise, but printing the current line now */`	274	`/* redo same exercise, but printing the current line now */`
276	`if (count == 0) {`	275	`if (count == 0) {`
277	`count = 1;`	276	`count = 1;`
278	`mdr_cout_char(screenlastrow, helpcol - coloffset, '/', SCHEME_STBAR1);`	277	`mdr_cout_char(screenlastrow, col--, '/', SCHEME_STBAR1);`
279	`coloffset++;`	-
280	`x = 1 + db->curline;`	278	`x = 1 + db->curline;`
281	`goto AGAIN;`	279	`goto AGAIN;`
282	`}`	280	`}`
283		281
284	`}`	282	`}`
285		283
286	`mdr_cout_str(screenlastrow, helpcol, s, SCHEME_STBAR2, 40);`	284	`mdr_cout_str(screenlastrow, helpcol, s, SCHEME_STBAR2, 40);`
287	`}`	285	`}`
288		286
289		287
290	`static void ui_msg(const char msg1, const char msg2, unsigned char attr) {`	288	`static void ui_msg(const char msg1, const char msg2, unsigned char attr) {`
291	`unsigned short x, y, msglen, i;`	289	`unsigned short x, y, msglen, i;`
292	`unsigned short msg2flag = 0;`	290	`unsigned short msg2flag = 0;`
293		291
294	`msglen = strlen(msg1);`	292	`msglen = strlen(msg1);`
295	`if (msg2) {`	293	`if (msg2) {`
296	`msg2flag = 1;`	294	`msg2flag = 1;`
297	`i = strlen(msg2);`	295	`i = strlen(msg2);`
298	`if (i > msglen) msglen = i;`	296	`if (i > msglen) msglen = i;`
299	`}`	297	`}`
300		298
301	`y = (screenh - 6) >> 1;`	299	`y = (screenh - 6) >> 1;`
302	`x = (screenw - msglen - 4) >> 1;`	300	`x = (screenw - msglen - 4) >> 1;`
303	`for (i = y+2+msg2flag; i >= y; i--) mdr_cout_char_rep(i, x, ' ', attr, msglen + 2);`	301	`for (i = y+2+msg2flag; i >= y; i--) mdr_cout_char_rep(i, x, ' ', attr, msglen + 2);`
304	`x++;`	302	`x++;`
305		303
306	`mdr_cout_str(y+1, x, msg1, attr, msglen);`	304	`mdr_cout_str(y+1, x, msg1, attr, msglen);`
307	`if (msg2) mdr_cout_str(y+2, x, msg2, attr, msglen);`	305	`if (msg2) mdr_cout_str(y+2, x, msg2, attr, msglen);`
308		306
309	`if (uidirty.from > y) uidirty.from = y;`	307	`if (uidirty.from > y) uidirty.from = y;`
310	`if (uidirty.to < y+4) uidirty.to = y+4;`	308	`if (uidirty.to < y+4) uidirty.to = y+4;`
311	`}`	309	`}`
312		310
313		311
314	`static unsigned char ui_confirm_if_unsaved(const struct file *db) {`	312	`static unsigned char ui_confirm_if_unsaved(const struct file *db) {`
315	`unsigned char r = 0;`	313	`unsigned char r = 0;`
316	`if (db->modflag == 0) return(0);`	314	`if (db->modflag == 0) return(0);`
317		315
318	`mdr_cout_cursor_hide();`	316	`mdr_cout_cursor_hide();`
319		317
320	`/* if file has been modified then ask for confirmation */`	318	`/* if file has been modified then ask for confirmation */`
321	`ui_msg(svarlang_str(0,4), svarlang_str(0,5), SCHEME_MSG);`	319	`ui_msg(svarlang_str(0,4), svarlang_str(0,5), SCHEME_MSG);`
322	`if (mdr_dos_getkey2() != '\r') r = 1;`	320	`if (mdr_dos_getkey2() != '\r') r = 1;`
323		321
324	`mdr_cout_cursor_show();`	322	`mdr_cout_cursor_show();`
325		323
326	`return(r);`	324	`return(r);`
327	`}`	325	`}`
328		326
329		327
330	`static void ui_refresh(const struct file *db) {`	328	`static void ui_refresh(const struct file *db) {`
331	`unsigned char x;`	329	`unsigned char x;`
332	`const struct line far *l;`	330	`const struct line far *l;`
333	`unsigned char y = db->cursorposy;`	331	`unsigned char y = db->cursorposy;`
334		332
335	`/* quit early if nothing to refresh */`	333	`/* quit early if nothing to refresh */`
336	`if (uidirty.from == 0xff) return;`	334	`if (uidirty.from == 0xff) return;`
337		335
338	`#ifdef DBG_REFRESH`	336	`#ifdef DBG_REFRESH`
339	`static char m = 'a';`	337	`static char m = 'a';`
340	`m++;`	338	`m++;`
341	`if (m > 'z') m = 'a';`	339	`if (m > 'z') m = 'a';`
342	`#endif`	340	`#endif`
343		341
344	`/* rewind cursor line to first line that needs redrawing */`	342	`/* rewind cursor line to first line that needs redrawing */`
345	`for (l = db->cursor; y > uidirty.from; y--) l = l->prev;`	343	`for (l = db->cursor; y > uidirty.from; y--) l = l->prev;`
346		344
347	`/* iterate over lines and redraw whatever needs to be redrawn */`	345	`/* iterate over lines and redraw whatever needs to be redrawn */`
348	`for (; l != NULL; l = l->next, y++) {`	346	`for (; l != NULL; l = l->next, y++) {`
349		347
350	`/* skip lines that do not need to be refreshed */`	348	`/* skip lines that do not need to be refreshed */`
351	`if (y < uidirty.from) continue;`	349	`if (y < uidirty.from) continue;`
352	`if (y > uidirty.to) break;`	350	`if (y > uidirty.to) break;`
353		351
354	`x = 0;`	352	`x = 0;`
355	`if (db->xoffset < l->len) {`	353	`if (db->xoffset < l->len) {`
356	`unsigned char i, limit;`	354	`unsigned char i, limit;`
357	`if (l->len - db->xoffset < screenw) {`	355	`if (l->len - db->xoffset < screenw) {`
358	`limit = l->len;`	356	`limit = l->len;`
359	`} else {`	357	`} else {`
360	`limit = db->xoffset + screenlastcol;`	358	`limit = db->xoffset + screenlastcol;`
361	`}`	359	`}`
362	`for (i = db->xoffset; i < limit; i++) mdr_cout_char(y, x++, l->payload[i], SCHEME_TEXT);`	360	`for (i = db->xoffset; i < limit; i++) mdr_cout_char(y, x++, l->payload[i], SCHEME_TEXT);`
363	`}`	361	`}`
364		362
365	`/* write empty spaces until end of line */`	363	`/* write empty spaces until end of line */`
366	`if (x < screenlastcol) mdr_cout_char_rep(y, x, ' ', SCHEME_TEXT, screenlastcol - x);`	364	`if (x < screenlastcol) mdr_cout_char_rep(y, x, ' ', SCHEME_TEXT, screenlastcol - x);`
367		365
368	`#ifdef DBG_REFRESH`	366	`#ifdef DBG_REFRESH`
369	`mdr_cout_char(y, 0, m, SCHEME_STBAR1);`	367	`mdr_cout_char(y, 0, m, SCHEME_STBAR1);`
370	`#endif`	368	`#endif`
371		369
372	`if (y == screenh - 2) break;`	370	`if (y == screenh - 2) break;`
373	`}`	371	`}`
374		372
375	`/* fill all lines below if empty (and they need to be redrawn) */`	373	`/* fill all lines below if empty (and they need to be redrawn) */`
376	`if (l == NULL) {`	374	`if (l == NULL) {`
377	`while ((y < screenlastrow) && (y < uidirty.to)) {`	375	`while ((y < screenlastrow) && (y < uidirty.to)) {`
378	`mdr_cout_char_rep(y++, 0, ' ', SCHEME_TEXT, screenlastcol);`	376	`mdr_cout_char_rep(y++, 0, ' ', SCHEME_TEXT, screenlastcol);`
379	`}`	377	`}`
380	`}`	378	`}`
381		379
382	`/* scroll bar */`	380	`/* scroll bar */`
383	`for (y = 0; y < screenlastrow; y++) {`	381	`for (y = 0; y < screenlastrow; y++) {`
384	`mdr_cout_char(y, screenlastcol, SCROLL_CURSOR, SCHEME_SCROLL);`	382	`mdr_cout_char(y, screenlastcol, SCROLL_CURSOR, SCHEME_SCROLL);`
385	`}`	383	`}`
386		384
387	`/* scroll cursor */`	385	`/* scroll cursor */`
388	`if (db->totlines >= screenh) {`	386	`if (db->totlines >= screenh) {`
389	`unsigned short topline = db->curline - db->cursorposy;`	387	`unsigned short topline = db->curline - db->cursorposy;`
390	`unsigned short col;`	388	`unsigned short col;`
391	`unsigned short totlines = db->totlines - screenh + 1;`	389	`unsigned short totlines = db->totlines - screenh + 1;`
392	`if (db->totlines - screenh > screenh) {`	390	`if (db->totlines - screenh > screenh) {`
393	`col = topline / (totlines / screenlastrow);`	391	`col = topline / (totlines / screenlastrow);`
394	`} else {`	392	`} else {`
395	`col = topline * screenlastrow / totlines;`	393	`col = topline * screenlastrow / totlines;`
396	`}`	394	`}`
397	`if (col >= screenlastrow) col = screenh - 2;`	395	`if (col >= screenlastrow) col = screenh - 2;`
398	`mdr_cout_char(col, screenlastcol, ' ', SCHEME_SCROLL);`	396	`mdr_cout_char(col, screenlastcol, ' ', SCHEME_SCROLL);`
399	`}`	397	`}`
400		398
401	`/* clear out the dirty flag */`	399	`/* clear out the dirty flag */`
402	`uidirty.from = 0xff;`	400	`uidirty.from = 0xff;`
403	`}`	401	`}`
404		402
405		403
406	`static void check_cursor_not_after_eol(struct file *db) {`	404	`static void check_cursor_not_after_eol(struct file *db) {`
407	`if (db->xoffset + db->cursorposx <= db->cursor->len) return;`	405	`if (db->xoffset + db->cursorposx <= db->cursor->len) return;`
408		406
409	`if (db->cursor->len < db->xoffset) {`	407	`if (db->cursor->len < db->xoffset) {`
410	`db->cursorposx = 0;`	408	`db->cursorposx = 0;`
411	`db->xoffset = db->cursor->len;`	409	`db->xoffset = db->cursor->len;`
412	`uidirty.from = 0;`	410	`uidirty.from = 0;`
413	`uidirty.to = 0xff;`	411	`uidirty.to = 0xff;`
414	`} else {`	412	`} else {`
415	`db->cursorposx = db->cursor->len - db->xoffset;`	413	`db->cursorposx = db->cursor->len - db->xoffset;`
416	`}`	414	`}`
417	`}`	415	`}`
418		416
419		417
420	`static void cursor_up(struct file *db) {`	418	`static void cursor_up(struct file *db) {`
421	`if (db->cursor->prev == NULL) return;`	419	`if (db->cursor->prev == NULL) return;`
422		420
423	`db->curline -= 1;`	421	`db->curline -= 1;`
424	`db->cursor = db->cursor->prev;`	422	`db->cursor = db->cursor->prev;`
425	`if (db->cursorposy == 0) {`	423	`if (db->cursorposy == 0) {`
426	`uidirty.from = 0;`	424	`uidirty.from = 0;`
427	`uidirty.to = 0xff;`	425	`uidirty.to = 0xff;`
428	`} else {`	426	`} else {`
429	`db->cursorposy -= 1;`	427	`db->cursorposy -= 1;`
430	`}`	428	`}`
431	`}`	429	`}`
432		430
433		431
434	`static void cursor_eol(struct file *db) {`	432	`static void cursor_eol(struct file *db) {`
435	`/* adjust xoffset to make sure eol is visible on screen */`	433	`/* adjust xoffset to make sure eol is visible on screen */`
436	`if (db->xoffset > db->cursor->len) {`	434	`if (db->xoffset > db->cursor->len) {`
437	`db->xoffset = db->cursor->len - 1;`	435	`db->xoffset = db->cursor->len - 1;`
438	`uidirty.from = 0;`	436	`uidirty.from = 0;`
439	`uidirty.to = 0xff;`	437	`uidirty.to = 0xff;`
440	`}`	438	`}`
441		439
442	`if (db->xoffset + screenlastcol <= db->cursor->len) {`	440	`if (db->xoffset + screenlastcol <= db->cursor->len) {`
443	`db->xoffset = db->cursor->len - screenw + 2;`	441	`db->xoffset = db->cursor->len - screenw + 2;`
444	`uidirty.from = 0;`	442	`uidirty.from = 0;`
445	`uidirty.to = 0xff;`	443	`uidirty.to = 0xff;`
446	`}`	444	`}`
447	`db->cursorposx = db->cursor->len - db->xoffset;`	445	`db->cursorposx = db->cursor->len - db->xoffset;`
448	`}`	446	`}`
449		447
450		448
451	`static void cursor_down(struct file *db) {`	449	`static void cursor_down(struct file *db) {`
452	`if (db->cursor->next == NULL) return;`	450	`if (db->cursor->next == NULL) return;`
453		451
454	`db->curline += 1;`	452	`db->curline += 1;`
455	`db->cursor = db->cursor->next;`	453	`db->cursor = db->cursor->next;`
456	`if (db->cursorposy < screenh - 2) {`	454	`if (db->cursorposy < screenh - 2) {`
457	`db->cursorposy += 1;`	455	`db->cursorposy += 1;`
458	`} else {`	456	`} else {`
459	`uidirty.from = 0;`	457	`uidirty.from = 0;`
460	`uidirty.to = 0xff;`	458	`uidirty.to = 0xff;`
461	`}`	459	`}`
462	`}`	460	`}`
463		461
464		462
465	`static void cursor_left(struct file *db) {`	463	`static void cursor_left(struct file *db) {`
466	`if (db->cursorposx > 0) {`	464	`if (db->cursorposx > 0) {`
467	`db->cursorposx -= 1;`	465	`db->cursorposx -= 1;`
468	`} else if (db->xoffset > 0) {`	466	`} else if (db->xoffset > 0) {`
469	`db->xoffset -= 1;`	467	`db->xoffset -= 1;`
470	`uidirty.from = 0;`	468	`uidirty.from = 0;`
471	`uidirty.to = 0xff;`	469	`uidirty.to = 0xff;`
472	`} else if (db->cursor->prev != NULL) { /* jump to end of line above */`	470	`} else if (db->cursor->prev != NULL) { /* jump to end of line above */`
473	`cursor_up(db);`	471	`cursor_up(db);`
474	`cursor_eol(db);`	472	`cursor_eol(db);`
475	`}`	473	`}`
476	`}`	474	`}`
477		475
478		476
479	`static void cursor_home(struct file *db) {`	477	`static void cursor_home(struct file *db) {`
480	`db->cursorposx = 0;`	478	`db->cursorposx = 0;`
481	`if (db->xoffset != 0) {`	479	`if (db->xoffset != 0) {`
482	`db->xoffset = 0;`	480	`db->xoffset = 0;`
483	`uidirty.from = 0;`	481	`uidirty.from = 0;`
484	`uidirty.to = 0xff;`	482	`uidirty.to = 0xff;`
485	`}`	483	`}`
486	`}`	484	`}`
487		485
488		486
489	`static void cursor_right(struct file *db) {`	487	`static void cursor_right(struct file *db) {`
490	`if (db->cursor->len > db->xoffset + db->cursorposx) {`	488	`if (db->cursor->len > db->xoffset + db->cursorposx) {`
491	`if (db->cursorposx < screenw - 2) {`	489	`if (db->cursorposx < screenw - 2) {`
492	`db->cursorposx += 1;`	490	`db->cursorposx += 1;`
493	`} else {`	491	`} else {`
494	`db->xoffset += 1;`	492	`db->xoffset += 1;`
495	`uidirty.from = 0;`	493	`uidirty.from = 0;`
496	`uidirty.to = 0xff;`	494	`uidirty.to = 0xff;`
497	`}`	495	`}`
498	`} else if (db->cursor->next != NULL) { /* jump to start of next line */`	496	`} else if (db->cursor->next != NULL) { /* jump to start of next line */`
499	`cursor_down(db);`	497	`cursor_down(db);`
500	`cursor_home(db);`	498	`cursor_home(db);`

Subversion Repositories SvarDOS

(root)/sved/trunk/sved.c @ 1777 – Rev 1438 → 1439