process.c File Reference

Process data structures and functions. More...

Macros
#define	__DEBUG_HEADER__   "[PROC ]"
	Change header.
#define	__DEBUG_LEVEL__   LOGLEVEL_NOTICE
	Set log level.

Functions
static int	__count_args (char **args)
	Counts the number of arguments. More...
static int	__count_args_bytes (char **args)
	Counts the bytes occupied by the arguments. More...
static char **	__push_args_on_stack (uintptr_t *stack, char *args[])
	Pushes the arguments on the stack. More...
static int	__reset_process (task_struct *task)
	Resets the process. More...
static int	__has_shebang (vfs_file_t *file)
	Checks if the file starts with a shebang. More...
static int	__load_executable (const char *path, task_struct *task, uint32_t *entry)
	Replace the current process with a loaded exectuable. More...
static task_struct *	__alloc_task (task_struct *source, task_struct *parent, const char *name)
	Allocates the memory for a task. More...
int	init_tasking (void)
	Initialize the task management. More...
task_struct *	process_create_init (const char *path)
	Create and spawn the init process. More...
char *	sys_getcwd (char *buf, size_t size)
	Get current working directory. More...
int	sys_chdir (char const *path)
	Changes the working directory. More...
int	sys_fchdir (int fd)
	Changes the working directory. More...
pid_t	sys_fork (pt_regs *f)
	Clone the calling process, but without copying the whole address space. The calling process is suspended until the new process exits or is replaced by a call to ‘execve’. More...
int	sys_execve (pt_regs *f)
	Replaces the current process image with a new process image. More...

Variables
static kmem_cache_t *	task_struct_cache
	Cache for creating the task structs.
static task_struct *	init_proc
	The task_struct of the init process.

Detailed Description

Process data structures and functions.

Copyright

(c) 2014-2024 This file is distributed under the MIT License. See LICENSE.md for details.

Function Documentation

__alloc_task()

static task_struct* __alloc_task ( task_struct *  source, task_struct *  parent, const char *  name  )

inlinestatic

Allocates the memory for a task.

Parameters

source	the source task we use for the copy.
parent	the parent process.
name	the name of the new process.

Returns

pointer to the newly allocated task.

__count_args()

static int __count_args ( char **  args )

inlinestatic

Counts the number of arguments.

Parameters

args	the array of arguments, it must be NULL terminated.

Returns

the number of arguments.

__count_args_bytes()

static int __count_args_bytes ( char **  args )

inlinestatic

Counts the bytes occupied by the arguments.

Parameters

args	the array of arguments, it must be NULL terminated.

Returns

the bytes occupied by the arguments.

__has_shebang()

static int __has_shebang ( vfs_file_t *  file )

static

Checks if the file starts with a shebang.

Parameters

file	the file to check.

Returns

1 if it contains a shebang, 0 otherwise.

__load_executable()

static int __load_executable ( const char *  path, task_struct *  task, uint32_t *  entry  )

static

Replace the current process with a loaded exectuable.

Parameters

path	the path to the executable to load.
task	the task to laod the exectuable.
entry

Returns

-errno or 0 on failure, 1 on success, 2 if a interpreter was loaded

__push_args_on_stack()

static char** __push_args_on_stack ( uintptr_t *  stack, char *  args[]  )

inlinestatic

Pushes the arguments on the stack.

Parameters

stack	pointer to the stack location.
args	the list of arguments.

Returns

the final position of the stack, where the list of pushed arguments is stored.

__reset_process()

static int __reset_process ( task_struct *  task )

static

Resets the process.

Parameters

task	the process to reset.

Returns

0 on failure, 1 otherwise.

init_tasking()

int init_tasking

(

void

)

Initialize the task management.

Returns

1 success, 0 failure.

process_create_init()

task_struct* process_create_init

(

const char *

path

)

Create and spawn the init process.

Parameters

path	Path of the init program.

Returns

Pointer to init process.

sys_chdir()

int sys_chdir

(

char const *

path

)

Changes the working directory.

Parameters

path	The new working directory.

Returns

On success 0. On error -1, and errno indicates the error.

sys_execve()

int sys_execve

(

pt_regs *

f

)

Replaces the current process image with a new process image.

Parameters

f	CPU registers whe calling this function.

Returns

0 on success, -1 on error.

sys_fchdir()

int sys_fchdir

(

int

fd

)

Changes the working directory.

Parameters

fd	File descriptor of the new working directory.

Returns

On success 0. On error -1, and errno indicates the error.

sys_fork()

pid_t sys_fork

(

pt_regs *

f

)

Clone the calling process, but without copying the whole address space. The calling process is suspended until the new process exits or is replaced by a call to ‘execve’.

Parameters

f	CPU registers whe calling this function.

Returns

Return -1 for errors, 0 to the new process, and the process ID of the new process to the old process.

sys_getcwd()

char* sys_getcwd	(	char *	buf,
		size_t	size
	)

Get current working directory.

Parameters

buf	The array where the CWD will be copied.
size	The size of the array.

Returns

On success, returns the same pointer to buf. On failure, returnr NULL, and errno is set to indicate the error.