Memory Management Simulation

Write a C++ program that simulates a simplified Memory Management system. When the program starts there will be 1 Meg (2²⁰) of available memory. Memory will be allocated in 512 byte memory blocks. Therefore, if a job requires 4 bytes of memory, it will allocate 1 block of memory (512 bytes), and if a job requires 513 bytes of memory it will allocate 2 blocks of memory (1024 bytes). Each job's memory must be a CONTIGUOUS block. If there isn't a block large enough available for a job, then the job doesn't allocate memory and the job is terminated. You will need to implement dynamic memory allocation algorithm using the " best-fit" for locating the block of memory to use for loading the new job. Best fit is using the smallest available memory block that will satisfy the request. I strongly suggest (not require) that you use a binary search to find the best available block.

The input file (input.txt) will consist of 3 fields.

Field 1: Action (char) - action to perform.

A = allocate memory block
P = write all the AllocatedMemBlock's to the output file in order from smallest to largest in size.
R = release memory block
S = stops the simulation
Z = simulates a reboot of the computer. All allocated memory is released. 1 Meg of contiguous memory is available.

Field 2: Process Id (unsigned int) – indicates the process id of the job

This field will be 0 if the action is P, S or Z

Field 3: Memory required (unsigned int) – amount of memory required by the job.

This field will be 0 if the action is P, R, S or Z

When your program first starts you need to dynamically allocate a memory allocation structure that indicates the available memory.

struct AllocatedMemBlock
{

   unsigned int ProcessId;
   unsigned int MemBlocks;
   unsigned int MemorySize;

};

Note: A Process Id of 0 indicates this block of memory is not being used by a job.

So after startup you should have a single AllocatedMemBlock with the following values:

Process Id = 0
MemBlocks = 2048   (1 Meg / 512 bytes/block)
MemorySize = 1048576 (1 Meg)

When you release a block of memory, DO NOT join your released block with other available blocks of memory.

Example input file.

Example output file (output.txt).

AllocatedMemBlock 1            
   Process Id = 0              
   MemBlocks = 2048            
   MemorySize = 1048576

AllocatedMemBlock 1
   Process Id = 1              
   MemBlocks = 4
   MemorySize = 2000           
AllocatedMemBlock 2            
   Process Id = 0
   MemBlocks = 2044
   MemorySize = 1046528

AllocatedMemBlock 1
   Process Id = 1
   MemBlocks = 4
   MemorySize = 2000
AllocatedMemBlock 2
   Process Id = 2
   MemBlocks = 8
   MemorySize = 4016
AllocatedMemBlock 3
   Process Id = 0
   MemBlocks = 2036
   MemorySize = 1042432

AllocatedMemBlock 1
   Process Id = 0
   MemBlocks = 4
   MemorySize = 2048
AllocatedMemBlock 2
   Process Id = 2
   MemBlocks = 8
   MemorySize = 4016
AllocatedMemBlock 3
   Process Id = 0
   MemBlocks = 2036
   MemorySize = 1042432

AllocatedMemBlock 1
   Process Id = 3
   MemBlocks = 1
   MemorySize = 500
AllocatedMemBlock 2
   Process Id = 0
   MemBlocks = 3
   MemorySize = 1536
AllocatedMemBlock 3
   Process Id = 2
   MemBlocks = 8
   MemorySize = 4016
AllocatedMemBlock 4
   Process Id = 0
   MemBlocks = 2036
   MemorySize = 1042432

AllocatedMemBlock 1
   Process Id = 0
   MemBlocks = 2048
   MemorySize = 1048576

Additional Requirements:

Your program must not leak memory. Your program should release all previous allocated memory blocks on a reboot action (Z).
Your program must use functions.
You are allowed to use C style arrays, std::arrays and vectors. You are NOT allowed to use linked list, queue or any other type of container.
You are allowed (encouraged) to use unique_ptr's.
You must include a header file with your function prototypes and include your header in your .cpp file. Header file must contain the minimum includes required for your header to compile on its own.

chrispaterson/cpp_memory_manager

Memory Management Simulation