The dc_parser_set_data() function allows to re-use a parser object for
multiple dives. The advantages of this feature are actually very limited
in practice. The reduction in memory consumption is almost negligible,
because the amount of internal state in the parser is typically very
small. But the implementation requires some additional complexity
because each backend needs code to reset its internal state. Therefore,
the function is removed and the data and size needs to be passed
directly to the dc_parser_new() and dc_parser_new2() functions instead.
Because keeping a reference to the data has also caused issues in the
past, especially for applications implemented in a garbage collected
language, the data will now also get copied internally.
Only a few dive computer backends (reefnet, aladin and memomouse)
require the clock parameters for parsing the date/time. Therefore,
those parameters are removed from the constructor function and
applications should set the clock parameters with the
dc_parser_set_clock() function instead.
The getopt function is defined in the unistd.h header file. This header
file is only available on posix compatible systems. For example, on
Windows it's not available when building without mingw.
Comparing signed and unsigned integer expressions can have unexpected
results because the signed integer will get promoted to an unsigned
integer. To avoid the warning, add an explicit cast to the unsigned
type, along with a check to catch negative values.
For applications supporting offline parsing (like libdivecomputer's own
dctool application), some device specific knowledge is still required in
order to map a particular model to the corresponding backend. The new
convenience function will take care of that internally.
The already existing dc_parser_new() function does the same, but
requires an open device handle, which makes it unsuitable for offline
parsing.
Libdivecomputer always uses metric units internally. But when reverse
engineering a device that stores everything using imperial units, it's
very convenient to be able to switch the output to imperial units too.