The second variant of the open or create functions were introduced to
maintain backwards compatibility. But after being removed from the
public api, these functions serve no purpose anymore, and can be removed
completely.
The vendor_product_parser_create() and vendor_product_device_open()
functions should be called indirectly, through the generic
dc_device_open() and dc_parser_new() functions. And the
vendor_product_extract_dives() functions are internal functions that
should never have been part of the public api in the first place.
The Cressi Drake is a mainly a freedive computer. The data format is
almost identical to the Leonardo. The main difference is that a single
dive now contains an entire freedive session. Each freedive in the
session is delimited with a 4 byte header containing the surface
interval and a special marker.
For dives with multiple gas mixes, an application doesn't have enough
info to figure out which one is the initial gas mix. Usually it's the
first gas mix, but that's not guaranteed. Reporting the intial gas mix
on the first sample avoids this problem.
Both the allocation and initialization of the object data structure is
now moved to a single function. The corresponding deallocation function
is intended to free objects that have been allocated, but are not fully
initialized yet. The public cleanup function shouldn't be used in such
case, because it may try to release resources that haven't been
initialized yet.
Instead of freeing the object data structure in the backend specific
cleanup function, the memory is now freed automatically in the base
class function. This reduces the amount of boilerplate code in the
backends. Backends that don't allocate any additional resources, do no
longer require a cleanup function at all.
The Cressi Leonardo does store an indicator for the ascent rate (e.g.
the number of arrows) in the upper two bits. This results in 4 possible
values, ranging from 0 to 3, with the following interpretation:
0.0 - 3.9 m/min No signal
4.0 - 7.9 m/min 1 Arrow
8.0 - 11.9 m/min 2 Arrows
12.0+ m/min 3 Arrows (with STOP icon)
Reported-By: Nick Shore <support@mac-dive.com>
When using up to 14 bits for the depth, the resulting values are too
large in some cases. Most likely the upper bits are used to store
something else. Even with only 11 bits, the resulting depth range
(0-204.7m) should still be more than sufficient.
Currently, each backend has it's own function to verify whether the
object vtable pointer is the expected one. All these functions can be
removed in favor of a single isintance function in the base class,
which takes the expected vtable pointer as a parameter.
Functions which are called through the vtable, don't need to verify the
vtable pointer, and those checks are removed.
The term "backend" can be confusing because it can refer to both the
virtual function table and the device/parser backends. The use of the
term "vtable" avoids this.
This is only a preliminary version. There is certainly some room for
improvement, but the basic functionality is already in place. That
should be sufficient for daily use, and possibles issues can always be
fixed when discovered.
