[PATCH 2/2] Add type for gaschange events, if missing

[Anton Lundin]

On 17 July, 2014 - Miika Turkia wrote:

> On Thu, Jul 17, 2014 at 10:05 AM, Anton Lundin <glance at acc.umu.se> wrote:
> 
> > On 12 July, 2014 - Miika Turkia wrote:
> >
> > > On Sat, Jul 12, 2014 at 3:21 PM, Anton Lundin <glance at acc.umu.se> wrote:
> > >
> > > > On 12 July, 2014 - Miika Turkia wrote:
> > > >
> > > > > On Sat, Jul 12, 2014 at 2:24 PM, Anton Lundin <glance at acc.umu.se>
> > wrote:
> > > > >
> > > > > > On 12 July, 2014 - Miika Turkia wrote:
> > > > > >
> > > > > > > Subsurface has saved gas change events without type attribute at
> > some
> > > > > > > point. Thus we need to add the type when reading in log files,
> > if it
> > > > is
> > > > > > > missing. (Gas change logic relies on the type field nowadays.)
> > > > > > >
> > > > > > > Fixes #617
> > > > > > > Fixes #600
> > > > > > >
> > > > > > > Signed-off-by: Miika Turkia <miika.turkia at gmail.com>
> > > > > > > ---
> > > > > > >  parse-xml.c | 6 ++++++
> > > > > > >  1 file changed, 6 insertions(+)
> > > > > > >
> > > > > > > diff --git a/parse-xml.c b/parse-xml.c
> > > > > > > index 5375e32..606e251 100644
> > > > > > > --- a/parse-xml.c
> > > > > > > +++ b/parse-xml.c
> > > > > > > @@ -1337,6 +1337,12 @@ static void event_end(void)
> > > > > > >                               pic->offset.seconds =
> > > > > > cur_event.time.seconds;
> > > > > > >                               dive_add_picture(cur_dive, pic);
> > > > > > >                       } else {
> > > > > > > +                             /* At some point gas change events
> > did
> > > > not
> > > > > > have any type. Thus we need to add
> > > > > > > +                              * one on import, if we encounter
> > the
> > > > type
> > > > > > one missing.
> > > > > > > +                              */
> > > > > > > +                             if (cur_event.type == 0 && strcmp(
> > > > > > cur_event.name, "gaschange") == 0)
> > > > > > > +                                     cur_event.type = 25;
> > > > > >
> > > > > > I would prefer if we used SAMPLE_EVENT_GASCHANGE2 instead of the
> > enum
> > > > > > number.
> > > > > >
> > > > > > Are you sure they are of type GASCHANGE2, aka with He? I would
> > guess
> > > > > > they where of type GASCHANGE , aka the ones without any He info.
> > > > > >
> > > > >
> > > > > All the test dives use type 25 even though there is no helium in
> > them and
> > > > > manually added gas change event uses hard coded 25 as well, so I
> > didn't
> > > > > realize it should change based on gas. I'll send a fix shortly...
> > > > >
> > > >
> > > > It depends on what format the source of the event was talking. There
> > are
> > > > DC's that only tell us the o2 content, even if the gas had a he-part.
> > > >
> > > > If you look at the get_cylinder_index function, if its a
> > > > SAMPLE_EVENT_GASCHANGE, just don't care about any he-parts when were
> > > > looking for the matching gas, eg:
> > > >
> > > > If a dive had a gaslist like:
> > > > * 21/35
> > > > * AIR
> > > >
> > > > Then a SAMPLE_EVENT_GASCHANGE with o2 = 21% would return the 21/35, its
> > > > the fist best match, but a SAMPLE_EVENT_GASCHANGE2 with o2 = 21% he =
> > 0%
> > > > would return the air because the 21/35 has helium in it and the event
> > > > says that the gas shouldn't have any helium in it.
> > > >
> > > >
> > > > I would say in the unknown event type case, if the event data has a he
> > > > part then its definitely a SAMPLE_EVENT_GASCHANGE2, otherwise i would
> > > > guess at a SAMPLE_EVENT_GASCHANGE, and let get_cylinder_index figure
> > the
> > > > rest out.
> > > >
> > >
> > > This patch should take care of adding proper type attribute for both XML
> > > import and manually added gas change events.
> > >
> > > miika
> >
> > > From e60b73cf33f79f144fc15705ac4f11645fed68e9 Mon Sep 17 00:00:00 2001
> > > From: Miika Turkia <miika.turkia at gmail.com>
> > > Date: Sat, 12 Jul 2014 15:51:03 +0300
> > > Subject: [PATCH] Detect proper event type based on helium content
> > >
> > > Select proper SAMPLE_EVENT_GASCHANGE "version" based on helium content
> > > on the mix.
> > >
> > > Signed-off-by: Miika Turkia <miika.turkia at gmail.com>
> > > ---
> > >  parse-xml.c | 5 +++--
> > >  1 file changed, 3 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/parse-xml.c b/parse-xml.c
> > > index 606e251..20eafc3 100644
> > > --- a/parse-xml.c
> > > +++ b/parse-xml.c
> > > @@ -11,6 +11,7 @@
> > >  #include <libxml/parserInternals.h>
> > >  #include <libxml/tree.h>
> > >  #include <libxslt/transform.h>
> > > +#include <libdivecomputer/parser.h>
> > >
> > >  #include "gettext.h"
> > >
> > > @@ -712,7 +713,7 @@ void add_gas_switch_event(struct dive *dive, struct
> > divecomputer *dc, int second
> > >       he = (he + 5) / 10;
> > >       value = o2 + (he << 16);
> > >
> > > -     add_event(dc, seconds, 25, 0, value, "gaschange"); /*
> > SAMPLE_EVENT_GASCHANGE2 */
> > > +     add_event(dc, seconds, he ? SAMPLE_EVENT_GASCHANGE2 :
> > SAMPLE_EVENT_GASCHANGE, 0, value, "gaschange");
> > >  }
> > >
> > >  static void get_cylinderindex(char *buffer, uint8_t *i)
> > > @@ -1341,7 +1342,7 @@ static void event_end(void)
> > >                                * one on import, if we encounter the type
> > one missing.
> > >                                */
> > >                               if (cur_event.type == 0 && strcmp(
> > cur_event.name, "gaschange") == 0)
> > > -                                     cur_event.type = 25;
> > > +                                     cur_event.type = cur_event.value
> > >> 16 > 0 ? SAMPLE_EVENT_GASCHANGE2 : SAMPLE_EVENT_GASCHANGE;
> > >
> > >                               add_event(dc, cur_event.time.seconds,
> > >                                         cur_event.type, cur_event.flags,
> >
> > I would say that this code is wrong.
> >
> > You can't choose between SAMPLE_EVENT_GASCHANGE and
> > SAMPLE_EVENT_GASCHANGE2 just based on if there is helium in the gas or
> > not.
> >
> > You should use SAMPLE_EVENT_GASCHANGE if the gaschange event only
> > contains the oxygen part of a gasmix, and SAMPLE_EVENT_GASCHANGE2 if the
> > event describes the whole gasmix.
> >
> 
> So in Subsurface we should always use SAMPLE_EVENT_GASCHANGE2? Unless
> libdivecomputer tells us otherwise? If I am finally understanding you...
>

I hope i didn't mess things up too badly for you.

Yes, if we added the event, we should always use
SAMPLE_EVENT_GASCHANGE2, but we can't assume that all events we read
without a event type will be SAMPLE_EVENT_GASCHANGE2.

//Anton

-- 
Anton Lundin	+46702-161604