cvs commit: httpd-python/src filterobject.c

[gr...@apache.org]

grisha      2003/05/04 19:23:28

  Modified:    src      filterobject.c
  Log:
  added some hopefully helpful explanation of the confusing subject of filters
  
  Revision  Changes    Path
  1.22      +40 -1     httpd-python/src/filterobject.c
  
  Index: filterobject.c
  ===================================================================
  RCS file: /home/cvs/httpd-python/src/filterobject.c,v
  retrieving revision 1.21
  retrieving revision 1.22
  diff -u -r1.21 -r1.22
  --- filterobject.c	23 Jan 2003 20:20:00 -0000	1.21
  +++ filterobject.c	5 May 2003 02:23:28 -0000	1.22
  @@ -66,6 +66,45 @@
   
   #include "mod_python.h"
   
  +/*** Some explanation of what is going on here:
  + *
  + * In Apache terminology, an "input" filter filters data flowing from
  + * network to application (aka "up"), an "output" filter filters data
  + * flowing from application to network (aka "down").
  + *
  + * An output filter is invoked as a result of ap_pass_brigade()
  + * call. It is given a populated brigade, which it then gives in the
  + * same fashion to the next filter via ap_pass_brigade(). (The filter
  + * may chose to create a new brigade pass that instead).
  + *
  + * An input filter is invoked as a result of ap_get_brigade() call. It
  + * is given an empty brigade, which it is expected to populate, which
  + * may in turn require the filter to invoke the next filter in the
  + * same fashion (via ap_get_brigade()).
  + *
  + * In mod_python Output filters: 
  + *
  + * filter.read() - copies data from *given* bucket brigade (saved in
  + * self->bb_in) into a Python string.
  + *
  + * filter.write() - copies data from a Python string into a *new*
  + * bucket brigade (saved in self->bb_out).
  + *
  + * filter.close() - passes the self->bb_out brigade to the next filter
  + * via ap_pass_brigade()
  + *
  + * In mod_python Input filters:
  + *
  + * filter.read() - copies data from a *new* and *populated via
  + * ap_get_brigade* (saved as self->bb_in) into a Python string.
  + *
  + * filter.write() - copies data from a Python string into a *given*
  + * brigade (saved as self->bb_out).
  + *
  + * filter.close() - is a noop.
  + *
  + */
  + 
   /**
    **     MpFilter_FromFilter
    **