Identify() function working

I was trying to understand the code base and for ARW files how does the identify function call in the open_datastream() function extract the meta-data from that file
I am not able to understand the control of how it would work , would be really useful if someone mentions the specific lines in identify.cpp which will be used for the ARW format or which functions are called in the pipeline

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ARW files are really TIFF

ARW files are really TIFF(like)-containers, so all ARW-specific code is specific tag values parsing/assignment to internal data structures.
The main analysis is common to all tiffs.

-- Alex Tutubalin @LibRaw LLC