#!/users/fdc/bin/wermit +
#
# ifdef2
#
# ifdef is a simple tool to check big C source files for 
# #if/#ifdef/#ifndef..#endif
# structure, handy for finding mismatches.
# ifdef2 also includes #define and #undef in the result.
#
# F. da Cruz, Columbia University, October 2009, November 2022
#
define display {
    .\%9 ::= (\m(depth) * 2) - 2
    echo "\flpad(\m(n),6). [\m(depth)] \frepeat(\32,\%9)\m(line)"
}
if not def \%1 exit 1 "usage: \%0 filename"
fopen /read \%c \%1
if fail exit 1
.depth = 0
.n = 0
while 1 {
    fread /line \%c line
    if fail break
    incr n
    .line := \fleft(\funtabify(\m(line)),40)
    if < \flen(\m(line)) 6 continue
    switch \m(line) {
      :#if*
        incr depth
        display
        break
      :#endif*
        display
        decr depth
        break
      :#define*
      :#undef*
        display
        break
      :default
        continue
    }
}
fclose \%c
exit