Start/stop acquisition callbacks: Consistently name the 'void *' parameter
cb_data for now. The per-device-instance device pointer is called
'session_dev_id' everywhere for now, but this should be renamed to
something more clear.
Avoid plain malloc()/free() in sr/srd, especially in the API calls.
Also avoid g_malloc*() in favor of g_try_malloc*().
Use g_strdup() instead of strdup() so that we can use g_free()
consistently everywhere.
Exceptions: Stuff that is allocated via other libs (not using glib),
should also be properly free'd using the respective free-ing function
(instead of g_free()). Examples: Stuff allocated by libusb, libftdi, etc.
Also, use sr_err() instead of sr_warn() for actual errors. sr_warn() is
meant for non-fatal/uncritical warnings.
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.
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.
In the lib, we should only #include "sigrok.h" or "sigrok-internal.h",
but not the (possibly installed and thus different/older versions) via
<sigrok.h> or <sigrok-internal.h>.
Frontends should of course use <sigrok.h> and <sigrok-internal.h>.
This is useful to allow frontends to react upon close failures in a
way they see fit (e.g. a popup in the GUI, or error message in the CLI).
They can also still ignore the error if they want, of course.
The g_malloc()/g_malloc0() versions exit/segfault if not enough memory
is available, which is not a good thing in libsigrok.
Instead, we use the g_try_malloc()/g_try_malloc0() variants, which
return NULL if not enough memory is available, so that the caller can
handle the error properly.
We should use these (internal) functions in libsigrok exclusively from
now on, i.e. no more use of glib's g_debug() etc.
These functions are only for libsigrok, the frontends use whatever
logging mechanism is suitable there.
support for metadata in recent versions of the FPGA code
moved constants and structs out to separate header file
got rid of all device instance-specific globals