#-h- detab.r         2908 asc 07-may-80 15:21:50
#-h- main             268 asc 07-may-80 15:21:40
 #--------------------------------------------------------------------
 #include symbols definitions
 #	include symbols
 #--------------------------------------------------------------------
##	detab -- main program
 
 
#	call initr4
#	call dotab
#	call endr4
#	end
 
#-h- dotab            746 asc 07-may-80 15:21:41
 ## dotab - driver for detab tool
# subroutine dotab 
 subroutine main
    character buf(MAXLINE)
    integer open, getarg, length, alldig
    integer tabs(MAXLINE), int, i, k, l
  
 
    call settab(tabs)   # set initial tab stops 
    int = ERR
  
     for (i=1; getarg(i, buf, MAXLINE) != EOF; i=i+1)
	{
	if (buf(1) == QMARK)
		call error ("usage:  detab [<t1>...] [+<n>] [file...]")
        if (buf(1) == PLUS | alldig(buf) == YES)	#ignore flags
		next
	if (buf(1) == MINUS & buf(2) == EOS)	#read from standard input
		int = STDIN
	else
		int = open(buf, READ)
	if (int == ERR)
		call cant(buf)
	call detab (tabs, int)
	if (int != STDIN)
		call close(int)
	}
   
    if (int == ERR)	#no files read
	call detab(tabs, STDIN)
    return
    end
#-h- detabs           603 asc 07-may-80 15:21:42
 ## detab - convert tabs to equivalent number of blanks
 subroutine detab (tabs, int)
 integer int
 character getch
 character c
 integer tabs(ARB)
 integer tabpos
 integer col
 
    col = 1 
    while (getch(c, int) != EOF) 
       if (c == TAB) 
          repeat { 
             call putc(BLANK) 
             col = col + 1 
             if (tabpos(col, tabs) == YES) 
                break 
             } 
       else if (c == NEWLINE) { 
          call putc(NEWLINE) 
          col = 1 
          } 
       else { 
          call putc(c) 
          col = col + 1 
          } 
    return 
    end 
#-h- settab           820 asc 07-may-80 15:21:42
 # settab - set initial tab stops 
    subroutine settab(tabs) 
    integer alldig
    integer tabs(MAXLINE), m, p, k, i, j, l 
    integer getarg, ctoi
    character n(4)
  
   p = 0 
   for (i=1; i<=MAXLINE; i=i+1) 
       tabs(i) = NO 
   for (j=1; getarg(j,n,4)!=EOF; j=j+1) 
       { 
       k=1 
       if (n(1) == PLUS) 
          k = k + 1 
       if (alldig(n(k)) == NO)
		next
       l = ctoi(n,k) 
       if (l<=0 | l>MAXLINE) 
          next 
       if (n(1)!=PLUS) 
          { 
          p = l 
          tabs(p) = YES 
          } 
       else 
          { 
          if (p==0) 
             p = l  + 1
          for (m=p; m<=MAXLINE; m=m+l) 
             tabs(m) = YES 
          } 
      } 
   if (p==0) 
      { 
      for (i=9; i<=MAXLINE; i=i+8) 
          tabs(i) = YES 
      } 
   return 
   end 
#-h- tabpos           226 asc 07-may-80 15:21:43
 # tabpos - return YES if col is a tab stop 
    integer function tabpos(col, tabs) 
    integer col, i, tabs(MAXLINE) 
  
    if (col > MAXLINE) 
       tabpos = YES 
    else 
       tabpos = tabs(col) 
    return 
    end