freebsd stable - Oct 2020 - calendar (1) - patch to correct error description

man calendar states:
  "The calendar internal cpp does not correctly do #ifndef and will discard
  the rest of the file if a #ifndef is triggered."
That is wrong, as proved by test file:
---
// Test data for ~/.calendar/calendar 
*	bla0
#ifdef DEBUG1
* 28	bla1
#endif
#ifdef DEBUG2
* 28	bla2
#endif
#ifndef DEBUG3
* 28	bla3
#endif
#define DEBUG4 TRUE
#ifndef DEBUG4
* 28	bla4
#endif
* 28	bla5
---
Produces:
---
Oct 28 	bla5
Oct 28 	bla4
Oct 28 	bla3
Oct 28 	bla2
Oct 28 	bla1
---
Correction:
  The calendar internal cpp ignores directives #ifdef , #ifndef and #endif ,
  and simply including intervening text regardless.
Patch built Wed Oct 28 12:39:27 CET 2020
on .ctm_status src-12 914 .svn_revision 366896 :
---
http://www.berklix.com/~jhs/src/bsd/fixes/freebsd/src/gen/usr.bin/calendar/calendar.1.ifdef.REL=12.2-STABLE.diff
*** 12.2-STABLE/src/usr.bin/calendar/calendar.1	Wed Oct 21 01:14:23 2020
--- new-generic/src/usr.bin/calendar/calendar.1	Wed Oct 28 12:33:12 2020
***************
*** 323,330 ****
  .Sh BUGS
  The
  .Nm
! internal cpp does not correctly do #ifndef and will discard the rest
! of the file if a #ifndef is triggered.
  It also has a maximum of 50 include file and/or 100 #defines
  and only recognises #include, #define and
  #ifndef.
--- 323,330 ----
  .Sh BUGS
  The
  .Nm
! internal cpp ignores directives #ifdef , #ifndef and #endif ,
! and simply including intervening text regardless.
  It also has a maximum of 50 include file and/or 100 #defines
  and only recognises #include, #define and
  #ifndef.
---

Later I could file this with send-pr, but before that I'm chasing
another calendar cpp error (maybe which cpp is used may need to be
considered, & that might reflect into discussion of which cpp used
on which BSDs)

Cheers,
-- 
Julian Stacey, Consultant Sys. Eng. BSD Linux Unix, http://berklix.com/jhs/cv/
Crash Brexit profits financial speculators in cabinet damaging Britain.
UK stole 3.7 million votes from Brits abroad 700 K in EU http://stolenvotes.uk

Am 28.10.20 um 13:02 schrieb Julian H. Stacey:
> man calendar states:
>    "The calendar internal cpp does not correctly do #ifndef and will
discard
>    the rest of the file if a #ifndef is triggered."
> That is wrong, as proved by test file:
> ---
> // Test data for ~/.calendar/calendar
> *	bla0
> #ifdef DEBUG1
> * 28	bla1
> #endif
> #ifdef DEBUG2
> * 28	bla2
> #endif
> #ifndef DEBUG3
> * 28	bla3
> #endif
> #define DEBUG4 TRUE
> #ifndef DEBUG4
> * 28	bla4
> #endif
> * 28	bla5
> ---
> Produces:
> ---
> Oct 28 	bla5
> Oct 28 	bla4
> Oct 28 	bla3
> Oct 28 	bla2
> Oct 28 	bla1
> ---
> Correction:
>    The calendar internal cpp ignores directives #ifdef , #ifndef and #endif
,
>    and simply including intervening text regardless.
Hi Julian,

no, the calendar program worked as documented, see the BUGS section of
the man-page:

.Sh BUGS
The
.Nm
internal cpp does not correctly do #ifndef and will discard the rest-of 
the file if a #ifndef is triggered.-It also has a maximum of 50 include 
file and/or 100 #defines and only recognises #include, #define and
#ifndef.

There is no mention of #ifdef being supported ...

And your "#ifndef DEBUG4" did not trigger, since the whole line after
#define is used as the identifier, in your case "DEBUG4 TRUE".

This is not obvious from reading the man-page and it might be more
intuitive, if the identifier was only the word up to the first blank,
but the code in the calendar program does just strip off leading and 
trailing white-space. It might be too late to change this behavior.

I have updated the code in -CURRENT to support #ifdef (MFC in 3 days)
and I plan to add supported for nested conditions in -CURRENT (not
sure whether that should be merged to -STABLE, though).

I could change the #define and #if/ifndef to only consider the first
following word, but do not plan to do that at this time.

Regards, STefan