ovwin.c

汇编语言编的关于ov143b.asm的小程序

/******************************************************************************
                        U P D A T E _ H E A D E R
 ******************************************************************************/

update_header() {      /* update display header */

   gotorc(VOL_ROW,1);                  /* make sure volume, directory, */
   out_str(cw.drivep->volbuf,11,' ');  /* file, tagged info is correct */

   if (!cw.showall) {                  /* display the current dir name */
      gotorc(VOL_ROW,PATH_COL+1);      /*   but if showall is in effect */
      out_str(cw.dirbuf,65,' ');       /*   its done somewhere else */
   }

   disp_vol_stats();
   disp_file_stats();

   gotorc(MASK_ROW,MASK_COL-1);        /* display the selection mask */
   disp_char(cw.maskcmp ? ' ' : '~');
   out_str(cw.mask,MASK_LEN,' ');

   gotorc(MASK_ROW+1,MASK_COL-1);      /* display the selection attributes */
   disp_attrib(cw.selatrs);
   disp_str(cw.selatrs & DIR ? " D" : " .");
}


/******************************************************************************
                        U P D A T E _ W I N D O W
 *****************************************************************************/

int ALTCALL
update_window(fptr)    /* display a window full of file info */
int fptr;
{
   int col;
   register int i, m;

   if (numwin > 1 || cw.showall)       /* display window header if > 1 */
      disp_dirname();                  /*   window or showall mode */

   /* display a window of file names */

   for (i = 0; i + cw.fnrow < cw.fnrow + cw.ndrows; i++) {

      gotorc(i+cw.fnrow,0);

      if (i < cw.nrows) {
         for (col = 0, m = cw.nbase + i; m < cw.nfiles; col++, m += cw.nrows)
            disp_file(&files[m],(m == cw.curidx && fptr));

         if (col < cw.ncols)   /* try to only clear on rows where less */
            clr_eol();         /* than ncols are displayed */
      } else
         clr_eol();
   }

   /* display files dir path if showall mode */

   if (fptr && cw.showall && cw.curidx < cw.nfiles)
      disp_path(cw.curidx);

   if (cw.nfiles == 0)         /* display a msg if no files in dir */
      disp_empty_msg(fptr);
}


/******************************************************************************
                        A D J U S T _ W I N D O W
 *****************************************************************************/

int ALTCALL
adjust_window() {

   /* for MS DOS, assume the max length file name is 13.  8 for the primary
      name, 1 for '.', 3 for the extension, and 1 for '\' if its a directory */

   cw.maxlen = MAX_NAMELEN + 1;

   /* everything depends on # files in directory */

   if (cw.nfiles == 0)                 /* unusual, but dir may be empty */
      cw.nrows = cw.ncols = 1;
   else {                              /* are files, calc logical rows, cols */
      cw.ncols = (cw.info_display) ? 1 : 5;
      cw.nrows = (cw.nfiles+(cw.ncols-1)) / cw.ncols;
   }

   cw.colsiz = SCREEN_COLS / cw.ncols;         /* width of each column */

   /* update current logical idx */

   if (cw.curidx >= cw.nfiles)
      cw.curidx = cw.nfiles ? cw.nfiles - 1 : 0;

   /* make sure nbase is setup such that the current file is displayed */

   if (cw.nfiles <= cw.ndrows * cw.ncols) /* if file entries will fit on */
      cw.nbase = 0;                       /*   1 screen, start at 1st */
   else {
      cw.nbase = idx2lr(cw.curidx) - cw.ndrows / 2;  /* try to center curidx */
      if (cw.nbase > 0 && cw.nbase + cw.ndrows > cw.nrows) /* no blank rows  */
         cw.nbase = cw.nrows - cw.ndrows;                  /* if possible    */
      if (cw.nbase < 0)                              /* might overshoot */
         cw.nbase = 0;
   }

}


/******************************************************************************
                             I N F O C N T
 *****************************************************************************/

infocnt(chg)           /* display/remove info header when required */
int chg;
{
   int cur_isnt_top;

   inwin += chg;                       /* more or less info windows */

   cur_isnt_top = (numwin > 1 && curwin != winlis);

   /* if the count of info windows just went to 0, or it just went from 0 to 1,
      we need to add or remove the info display header.  The top display
      window losses or gains a row when this happens */

   if ((inwin == 0 && chg) || (inwin == 1 && chg > 0)) {

      /* do a temp switch to the top window if not already there */

      if (cur_isnt_top) {
         wincpy(curwin,&cw);
         savefiles(cw.save_files,cw.nfiles);
         wincpy(&cw,winlis);
         restorefiles(cw.save_files,cw.nfiles);
      }

      /* now add or remove a row from the window */

      if (inwin) {                     /* remove a line, display header */
         cw.fwrow++;  cw.fnrow++;
         cw.wrows--;  cw.ndrows--;
         infohead();
      } else {                         /* add a line, remove header */
         cw.fwrow--;  cw.fnrow--;
         cw.wrows++;  cw.ndrows++;
      }

      /* now update the top window display, but don't bother if the current
         window is the top window - it will be updated by caller */

      if (cur_isnt_top) {
         adjust_window();      /* calculate #rows, columns, etc to display */
         update_window(0);
      }

      /* restore windows if we did a temp switch above */

      if (cur_isnt_top) {
         wincpy(winlis,&cw);
         savefiles(cw.save_files,cw.nfiles);
         wincpy(&cw,curwin);
         restorefiles(cw.save_files,cw.nfiles);
      }
   }
}


/*****************************************************************************
                      D I S P _ E M P T Y _ M S G
 *****************************************************************************/

static int ALTCALL
disp_empty_msg(on)     /* display empty dir msg w/wo highlighting */
int on;
{
   if (on)
      setvattrib(DIS_HIGH);

   disp_str_at("No files!",cw.fnrow+1,SCREEN_COLS/2-5);

   if (on)
      setvattrib(DIS_NORM);
}


/*****************************************************************************
                        D I S P _ D I R N A M E
 *****************************************************************************/

disp_dirname() {       /* display the dir name header */

   char allmsg[20];

   if (cw.showall) {                   /* special header if showall mode */

      strcpy(allmsg,"FILES ON DRIVE ");
      strncat(allmsg,cw.dirbuf,2);
      center_text(cw.fwrow,allmsg);

   } else

      center_text(cw.fwrow,cw.dirbuf);    /* disp the dir name */
}


/*****************************************************************************
                          I N F O H E A D
 *****************************************************************************/

infohead() {           /* display the info header */

   setvattrib(DIS_HEAD);
   disp_str_at("      NAME           USED  ALLOCATED     DATE         TIME      R H S A DIR",
      FIRST_NROW,0);
   clr_eol();
   setvattrib(DIS_NORM);
}


/*****************************************************************************
                            S H O W _ A L L
 *****************************************************************************/

show_all() {

   if (anyshowall && !cw.showall)      /* only one window can do showall */
      show_error(0,ONE_SH_ALL,1,"Only one window can show all files!");

   if (cw.showall ^= 1) {      /* toggle showall mode */

      /* showall mode is being turned on, allocate space for dir name ptrs */

      if ((dirlst = (char **) calloc(MAX_DIR,sizeof(char *))) == NULL) {
         cw.showall = 0;
         show_error(0,NO_MEM,1,"Out of memory!  Show All is not active!");
      }

      if (numwin == 1) {       /* make row for showall header if not already */
         cw.fnrow++;
         cw.ndrows--;
      }

      anyshowall = TRUE;       /* yes, a window has showall turned on */

   } else              /* showall is being turned off */

      showoff();

   renew_window();     /* redo window with/without showall mode */
}

/*****************************************************************************
                              S H O W O F F
 *****************************************************************************/

showoff() {            /* turn off show all mode */

   register int i;
   register char **cp;

   for (i = 0, cp = dirlst; i < diridx; i++, cp++)     /* release dir name */
       free(*cp);                                      /*   memory */

   free((char *)dirlst);       /* now release pointer memory */

   diridx = 0;                 /* reset for next time */
   dirlst = NULL;

   cw.showall = anyshowall = FALSE;    /* no window has showall now */

   if (numwin == 1) {          /* release showall header line if not needed */
      cw.fnrow--;
      cw.ndrows++;
   }
}


/******************************************************************************
                              W I N C P Y
 ******************************************************************************/

static int ALTCALL
wincpy(to,from)        /* copy window structures - I made this a separate */
WINDOW *to, *from;     /* routine cause MSC generates a bunch of code for */
{                      /* each structure asignment - in reality, it just a */
                       /* little more than the code required to call this */
                       /* function, but... */

   *to = *from;        /* not much to look at */
}


/******************************************************************************
 **                  S A V E / R E S T O R E  F I L E S                      **
 ******************************************************************************/

static int ALTCALL
savefiles(fp,nf)       /* copy files[] to save area */
char far *fp;
int nf;
{
   movedata(dataseg,(unsigned int) files,FP_SEG(fp),FP_OFF(fp),
             nf * sizeof(FILE_ENT));
}

static int ALTCALL
restorefiles(fp,nf)    /* copy files[] from save area */
char far *fp;
int nf;
{
   movedata(FP_SEG(fp),FP_OFF(fp),dataseg,(unsigned int) files,
            nf * sizeof(FILE_ENT));
}