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#pragma once
#include "config.h"
#include "mm/pagetable.h"
#include "proc/kthread.h"
#include "types.h"
#include "vm/vmmap.h"
/*===========
* Structures
*==========*/
/*
* Process resource information
*/
#define PROC_MAX_COUNT 65536
#define PROC_NAME_LEN 256
/* Process states */
typedef enum
{
PROC_RUNNING, /* Has running threads */
PROC_DEAD /* Exited, but not yet wait'ed */
} proc_state_t;
/* Process descriptor */
typedef struct proc
{
pid_t p_pid; /* Process ID */
char p_name[PROC_NAME_LEN]; /* Process name */
list_t p_threads; /* Threads list */
list_t p_children; /* Children list */
struct proc *p_pproc; /* Parent process */
list_link_t p_list_link; /* Link of list of all processes */
list_link_t p_child_link; /* Link on parent's list of children */
long p_status; /* Exit status */
proc_state_t p_state; /* Process state */
pml4_t *p_pml4; /* Page table. */
/*
* If a parent is waiting on a child, the parent puts itself on its own
* p_wait queue. When a child terminates, it broadcasts on its parent's
* p_wait to wake it up.
*/
ktqueue_t p_wait;
/* VFS related */
struct file *p_files[NFILES]; /* Open files */
struct vnode *p_cwd; /* Current working directory */
/* VM related */
/*
* The current value of a process's break is maintained in the 'p_brk'.
*
* The 'p_brk' and 'p_start_brk' members of a proc_t struct are initialized
* by the loader. 'p_start_brk' is subsequently never modified; it always
* holds the initial value of the break.
*
* The loader sets 'p_start_brk' to be the end of the bss section (search
* online for memory layout diagrams of a running process for more
* details).
*
* These are both addresses.
*/
void *p_brk; /* Process break; see brk(2) */
void *p_start_brk; /* Initial value of process break */
struct vmmap *p_vmmap; /* List of areas mapped into process's
user address space. */
} proc_t;
/*==========
* Functions
*=========*/
/**
* Initializes the proc subsystem at system startup.
*/
void proc_init(void);
/**
* Initializes the special idleproc at system startup.
*/
void proc_idleproc_init();
/**
* Shuts down certain subsystems at system shutdown.
*/
void initproc_finish();
/**
* Allocates and initializes a new process.
*
* @param name the name to give the newly created process
* @return the newly created process
*/
proc_t *proc_create(const char *name);
/**
* Frees all the resources associated with a process.
*
* @param proc process to destroy
*/
void proc_destroy(proc_t *proc);
/**
* Handles exiting the current process.
*
* @param retval exit code for the thread and process
*/
void proc_thread_exiting(void *retval);
/**
* Stops another process from running again by cancelling all its
* threads.
*
* @param proc the process to kill
* @param status the status the process should exit with
*/
void proc_kill(proc_t *proc, long status);
/**
* Kills every process except for the idle process and direct children
* of the idle process.
*/
void proc_kill_all(void);
/*========================
* Functions: System calls
*=======================*/
/**
* Implements the _exit(2) system call.
*
* @param status the exit status of the process
*/
void do_exit(long status);
/**
* Implements the waitpid(2) system call.
*
* @param pid the pid to wait on, or -1 to wait on any child
* @param status used to return the exit status of the child
* @param options only 0 is supported (no options)
*
* @return the pid of the child process which was cleaned up, or
* - ENOTSUP invalid input
* - ECHILD valid child could not be found
*/
pid_t do_waitpid(pid_t pid, int *status, int options);
/**
* This function implements the fork(2) system call.
*
* @param regs the register state at the time of the system call
*/
struct regs;
long do_fork(struct regs *regs);
/*===========
* Miscellany
*==========*/
/*
* Special PIDs reserved for specific processes
*/
#define PID_IDLE 0
#define PID_INIT 1
/*
* Enable global use of idleproc
*/
extern proc_t idleproc;
/*=====================
* Functions: Debugging
*====================*/
/**
* Provides detailed debug information about a given process.
*
* @param arg a pointer to the process
* @param buf buffer to write to
* @param osize size of the buffer
* @return the remaining size of the buffer
*/
size_t proc_info(const void *arg, char *buf, size_t osize);
/**
* Provides debug information overview of all processes.
*
* @param arg must be NULL
* @param buf buffer to write to
* @param osize size of the buffer
* @return the remaining size of the buffer
*/
size_t proc_list_info(const void *arg, char *buf, size_t osize);
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