Summary

Add clhsdb "findsym" command to map a native symbol name to its address.

Problem

Clhsdb currently provides no way to map a native symbol to its address. This can be very useful for doing things like examining hotspot global variables.

Solution

Provide a "findsym" command that will map a native symbol to its address. The contents of the address can the be looked at using the existing "examine" command. This is an example clhsdb session:

hsdb> findsym MaxJNILocalCapacity
0x00007f10a8343da0: /scratch/cplummer/ws/jdk/jdk.clean/build/linux-x64-slowdebug/images/jdk/lib/server/libjvm.so + 0x1d81da0
hsdb> findpc 0x00007f10a8343da0
Address 0x00007f10a8343da0: MaxJNILocalCapacity
hsdb> examine 0x00007f10a8343da0
0x00007f10a8343da0: 0x0000000000010000 

And 0x10000 is the default value for MaxJNILocalCapacity as seen in globals.hpp.

Specification

The clhsdb "help" output will include an entry for this new command:

hsdb> help
Available commands:
...
  findpc address
  findsym name
...
hsdb> help findsym
Usage: findsym name