MQ is the measured quantity, e.g. voltage, current, temperature.
UNIT is the unit in which these quantities are measured, e.g. volt,
ampere, celsius, kelvin, etc. etc.
The same MQ can be specified in different UNITs by the driver, depending
on what the hardware reports. Conversion is left to the frontends.
This will come back in some form or another later, but for now
don't clutter the API with non-working stuff. Removing stuff from APIs
is not possible without breaking the API, adding stuff later is simpler.
Use SR_API to mark public API symbols, and SR_PRIV for private symbols.
Variables and functions marked 'static' are private already and don't
need SR_PRIV. However, functions which are not static (because they need
to be used in other libsigrok-internal files) but are also not meant to
be part of the public libsigrok API, must use SR_PRIV.
This uses the 'visibility' feature of gcc (requires gcc >= 4.0).
Details: http://gcc.gnu.org/wiki/Visibility
The API should be generic and only provide sr_device_instance_new() and
friends, but not sr_usb_device_instance_new(), sr_serial_device_instance_new(),
or others for other device types we may have in the future. The
frontends shouldn't have to know or care about this implementation detail.
This also fixes the problem that parts of sigrok.h contained
'#ifdef HAVE_LIBUSB_1_0' and such, which is even less desirable for the API.
The usb/serial instance specifics are now private, and each driver that
needs them keeps a pointer in its driver-specific context.
For now, there's no analog/scope support in sigrok yet (will be added
later), so remove any such items from the public API (sigrok.h).
Having '#if defined(HAVE_LA_ALSA)' in sigrok.h is a bug anyway, the API
must not have anything device-dependent in general, and sigrok.h
specifically must not have any #ifdefs for specific hardware.
These version numbers represent the sigrok version (i.e., the version
of the tarball, such as "sigrok-0.2.0.tar.gz"), but _not_ the libsigrok
(libtool) library/API/ABI versions. Thus, they should not be in
libsigrok's include file (sigrok.h).