ov.c

汇编语言编的关于ov143b.asm的小程序

   adjust_window();                    /* set # rows, cols, etc */

   getchr();                           /* any keypress to continue */

   menu_row = MENU_ROW;                /* initialize menu subsystem */
   menu_hilite = DIS_HIGH;
   menu_lolite = DIS_NORM;
   top_menu = top_file_menu;

   setup_file_scr();                   /* display the static screen image */
   update_header();                    /* display header info */
   update_window(1);                   /*   and a window of data */

   grabbrk(&brkhit);           /* grab the ^Break/^C interrupt handler */

   /* call setjmp to establish the error handling jmp_buf,  errors in
      subfuntions will return here to start the next command */

   setjmp(back_to_main);

   /* main processing, obey each user command, terminate when done or
      user enters the EOF character or hits ^Break/^C */

   while (1) {
      obey();             /* only returns after ^Z or ^Break/^C */
      quit();             /* doesn't return if quitting */
   }

}


/******************************************************************************
 **                           O B E Y                                        **
 *****************************************************************************/

obey() {               /* obey / process a user command */

   register int ch, i;
   char *dp, *dirplus();

   menu_init();                /* display the initial menu */

   while ((ch = getchr()) != EOF_CH) { /* get a char from the user */

      brkhit = 0;              /* clr brk flag before each ov command */

      switch (ch) {

         case LEFT: case RIGHT:        /* left, right arrows */
         case UP:   case DOWN:         /* up, down arrows */
         case HOME: case END:
         case PGDN: case PGUP:

            if (dir_display)
               dir_move(ch);           /* move the dir pointer */
            else if (view_display)
               view_move(ch);          /* move within the view buffer/file */
            else if (def_display)
               def_move(ch);           /* move within define screen mode */
            else if (!restricted)
               move_file(ch);          /* move the file pointer */

            break;


         case ' ': case 9:             /* advance the menu selection pointer */
            menu_advance();
            break;


         case 8:                       /* backup the menu selection pointer */
            menu_backup();
            break;


         case RETURN:                  /* CR - do current menu selection */
            menu_do_current();
            break;


         case 27:                      /* escape - return to top menu */
            menu_init();               /* reset the menu subsystem */
            break;


         case TAG:                     /* single key command to tag current */
            if (!restricted && !def_display) {
               tag_current();
               if (cw.curidx < cw.nfiles-1)
                  move_file(DOWN);
            }
            break;


         case GOPAR:                   /* login to the parent dir */
            if (dir_display)
               dir_move(GOPAR);
            else
               if (!restricted) {
                  switch_dir(dp = dirplus(&files[cw.curidx],".."));
                  free(dp);
                  menu_init();
               }
            break;

         case GOSUB:                   /* login to dir under file ptr */
            if (dir_display) {
               dir_login();
               menu_init();
            } else {
               if (!restricted)
                  if (files[cw.curidx].flags & DIR) {
                     switch_dir(dp = dirplus(&files[cw.curidx],
                                             files[cw.curidx].name));
                     free(dp);
                     menu_init();
                  } else
                     tone(100,5);      /* beep the users mistake */
            }
            break;

         case NEXTT:                   /* goto next tagged file/find string */
         case PREVT:                   /* goto prev tagged file/find string */
            if (view_display)
               vfind(ch == NEXTT);
            else if (!restricted)
               tag_find(ch == NEXTT ? 1 : -1);
            break;

         case OPENW:                   /* open another file display window */
            if (!restricted)
               win_open();
            break;

         case CLOSEW:                  /* close current file display window */
            if (!restricted)
               win_close();
            break;

         case NEXTW:                   /* goto next file display window */
            if (!restricted)
               win_next();
            break;

         case PREVW:                   /* goto prev file display window */
            if (!restricted)
               win_prev();
            break;

         default:                      /* see if menu choice or UDK */

            if (ch >= UDK_START && ch <= UDK_END) {    /* UDK? */
               if (!restricted && !def_display) {
                  do_udk(ch);
                  menu_init();
               }
               break;
            }

            /* is it a menu selection? */

            if (!menu_do_char(ch))     /* do menu selection starting with ch */
               tone(100,5);            /* beep if not a valid selection */
            break;

      }

      if (winupdate) {                 /* some commands ask for one or */
         refresh_screen(1);            /* more windows to be updated */
         update_header();              /* make sure header is current */
         winupdate = 0;
      }
   }
}


/******************************************************************************
 **                             Q U I T                                      **
 *****************************************************************************/

quit() {               /* exit from overview */

   int ch;

   /* Ask the user if he really wants to exit (default = N).  If so, check
      to see if we are still in the initial startup dir.  If so, just exit.
      If not, ask if we should return to the original dir before
      quitting (default = return). */

   ch = ask("Quit OVERVIEW and return to DOS? (y/N): ");

   if (yes(ch)) {

      getcwd(cw.dirbuf,MAX_PATHLEN);   /* can mess cw.dibuf up cause quitting */

      if (strcmp(initialdir,cw.dirbuf) != 0) {
         ch = ask("Exit to current directory, or Return to original? (e/R): ");
         if (toupper(ch) != 'E')
            change_dir(initialdir);
      }
      reset_tty();                     /* restore pre OV tty settings */
      exit();                          /* So long, thanks for all the fish */
   }
}