5 https://git.automotivelinux.org/apps/agl-service-signal-composer/plain/docs/part-1/3-Plugins.md?h=master
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12 Plugins are C/C++ shared libraries loaded by the binding to execute some
13 simple routine. Routine could be on reception of a new signal or at sources
14 initialization time or signal subscription with the respective JSON field
15 `onReceived` `init` and `getSignals`
17 A default plugin (builtin) is provided with 2 functions:
19 - **defaultOnReceived**: set and record a new signal value and its timestamp
20 in the signal composer service. It simply tooks the incoming event JSON object
21 and search for *key* `value` and `timestamp` then call function
23 - **setSignalValueWrap**: a `lua2c` function the could be called from any LUA
24 script to record a new signal value.
26 > **CAUTION**: `timestamp` value has to be typed as *uint64_t* with
27 > a **nanosecond** precision using a realtime clock. To correctly store it in
28 > a JSON-C object use the int64 type with the according fonctions:
29 > *json_object_new_int64()*
30 > *json_object_get_int64()*
31 > *json_object_set_int64()*