This is required for some hardware, e.g. ChronoVu LA8, where
33.333333 MHz or 2.439024 MHz are valid samplerates. This is because the
hardware takes a sampleperiod (in nanoseconds) as input, not a
samplerate (in Hz).
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.
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
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>.
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.
Joel Holdsworth
Bert Vermeulen
Uwe Hermann
Gareth McMullin