Creating a New Process

Creating a New Process

This explains what happens when the kernel creates a new process

1. The function process_t createProcess(uint executableLocation) is called
2. The kernel creates a new process_t
3. Increment uint16_t nextPID
4. If nextPID overflows, return
5. Otherwise, set uint16_t PID to nextPID
6. The kernel then runs through memory until it runs into the EOF characters, recording how large the file is
7. Next, the kernel attempts to allocate the smallest block that will fit the executable by calling void* allocateBlock(uint8_t size)
8. If the kernel cannot allocate a block, it will return a null pointer
9. If the kernel can allocate a block, it will reserve the memory block in the memory table and return a pointer to the memory block
10. Set int* stackPointer to the processes stack
11. Set pageTable_t* pageTable to a newly created pageTable_t
12. Get the first process
13. Get the first processes process_t* previousProcess
14. Set that processes process_t* nextProcess to the new process
15. Set the new processes previousProcess to the first processes previousProcess
16. Set the first processes previousProcess to the new process
17. And set the new processes nextProcess to the first process