-- Author: Prokash Sinha, prokash@garlic.com.

-- How to build: There is a simple Makefile in the same directory, use the followng command on a tty terminal
	$ make

It should build libmemstats.so in the same directory where you have other files.

-- How to install:  From terminal execute the following command.
	$ export LD_PRELOAD=/home/prokash/verkeda/libmemstats.so

-- How to uninstall: From the current tty session
	$ export LD_PRELOAD=


-- How to run:  This is a linux shared object ( .so ) file. Anytime you execute a command from the same terminal window it would start executing. For example: $python. Hit enter every now and then on the python interpreter and see the output.

-- Unix distribution: Linux prokash-Kudu 4.2.0-42-generic #49-Ubuntu SMP Tue Jun 28 21:26:26 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux

-- GCC : gcc (Ubuntu 5.2.1-22ubuntu2) 5.2.1 20151010
Copyright (C) 2015 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.



Satus Notes:

	Used the link -- https://www.gnu.org/software/libc/manual/html_node/Hooks-for-Malloc.html  for getting the idea. 

	Compiler should have aligned allocation, so did not use the realign hook

	UTC time format is not worked, so just plain local time.

	Instead of ### in the print, it is just number of bytes.

Testing:

	local testing using $ gcc main.c seems to be working.
	$ ./a.out 100  /* to loop thru 100 times 1 sec pause between iter.

	find .   or find /  working

	python and google-chrome does not work. One of the malloc that adjust
	the allocation to keep size ( since free does not have size as an arg)
        allocates correctly, but free( void*) does not go thru the shared obj.

Complexity:

	Since the aging is based on time, Hash Tables are used to minimize 
	the Inset and Remove time of memory allocations and free. 
	Address table H has size 0xffff
	whereas Time table T has size 0xfffff(roughly 24 days to wrap around).

Alternative Approach:

	dlsym method could be tried to hook directly into the memory routines,
	since the __malloc_hook and friends are depricated.