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#pragma once
#include <kernel/arch/generic.h>
#include <kernel/handle.h>
#include <stdbool.h>
struct vfs_mount;
#define HANDLE_MAX 16
/* legal transitions described by process_transition */
enum process_state {
PS_RUNNING,
PS_DYING, /* during process_kill - mostly treated as alive */
PS_TOREAP, /* return message not collected */
PS_TOMBSTONE, /* fully dead, supports alive children */
/* not in the process tree, waits for free.
* *sibling holds a linked list of all the FORGOTTEN processes */
PS_FORGOTTEN,
PS_FREED, /* only meant to detect double frees */
PS_WAITS4CHILDDEATH,
PS_WAITS4FS,
PS_WAITS4REQUEST,
PS_WAITS4PIPE,
PS_WAITS4TIMER,
PS_LAST,
};
#define proc_alive(p) (p \
&& p->state != PS_TOREAP \
&& p->state != PS_TOMBSTONE \
&& p->state != PS_FORGOTTEN \
&& p->state != PS_FREED \
)
struct process {
struct pagedir *pages;
/* if NULL, refcount == 1. kmalloc'd */
uint64_t *pages_refcount;
struct registers regs;
struct process *sibling, *child, *parent;
enum process_state state;
union { /* saved value, meaning depends on .state */
int death_msg; // PS_DEAD
struct {
char __user *buf;
size_t max_len;
struct ufs_request __user *res;
} awaited_req; // PS_WAITS4REQUEST
struct {
struct handle *pipe;
char __user *buf;
size_t len;
struct process *next;
} waits4pipe;
struct {
/* managed by timer_schedule */
uint64_t goal;
struct process *next;
} waits4timer;
};
struct vfs_mount *mount;
struct handle **_handles; /* points to struct handle *[HANDLE_MAX] */
uint64_t *handles_refcount; /* works just like pages_refcount */
struct {
struct handle *procfs;
} specialh;
uint32_t cid; /* child id. unique amongst all of this process' siblings */
uint32_t nextcid; /* the child id to assign to the next spawned child */
uint32_t globalid; /* only for internal use, don't expose to userland */
uint32_t refcount; /* non-owning. should always be 0 on kill */
bool noreap;
/* allocated once, the requests from WAITS4FS get stored here */
struct vfs_request *reqslot;
/* vfs_backend controlled (not exclusively) by this process */
struct vfs_backend *controlled;
struct {
void *buf;
size_t len;
size_t pos;
} execbuf;
};
extern struct process *process_current;
/** Creates the root process. */
struct process *process_seed(void *data, size_t datalen);
struct process *process_fork(struct process *parent, int flags);
void process_kill(struct process *proc, int ret);
/** Kills all descendants. */
void process_filicide(struct process *proc, int ret);
/** Tries to reap a dead process / free a tombstone. */
void process_tryreap(struct process *dead);
/** Switches execution to any running process. */
_Noreturn void process_switch_any(void);
/** Used for iterating over all processes */
struct process *process_next(struct process *p, struct process *root);
handle_t process_find_free_handle(struct process *proc, handle_t start_at);
struct handle *process_handle_get(struct process *, handle_t);
handle_t process_handle_init(struct process *, enum handle_type, struct handle **);
handle_t process_handle_dup(struct process *p, handle_t from, handle_t to);
static inline void process_handle_close(struct process *p, handle_t hid) {
// TODO test
process_handle_dup(p, -1, hid);
}
/* Gets a handle and removes the process' reference to it, without decreasing the refcount.
* Meant to be used together with process_handle_put. */
struct handle *process_handle_take(struct process *, handle_t);
/* Put a handle in a process, taking the ownership away from the caller.
* Doesn't increase the refcount on success, decreases it on failure. */
handle_t process_handle_put(struct process *, struct handle *);
void process_transition(struct process *, enum process_state);
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