#include <fcntl.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
#include <signal.h>
#include <unistd.h>
#include <limits.h>
#include <assert.h>
#include <sys/types.h>
#include <sys/param.h>
#include <sys/file.h>
#include <sys/mman.h>
#include <sys/ipc.h>
#include <sys/sem.h>
#include <gu_util.h>
#include "gusimplewhiteboard.h"
#include "guwhiteboardtypelist_c_generated.h"

Include dependency graph for gusimplewhiteboard.c:

Macros
#define	_XOPEN_SOURCE

#define	__block _xblock

#define	__block __attribute__((__blocks__(byref)))

#define	WHITEBOARD_MAGIC 0xfeeda11deadbeef5ULL

#define	SEMAPHORE_MAGIC_KEY 4242

#define	SEM_ERROR -1

#define	SEM_A 0200 /* alter permission */

#define	SEM_R 0400 /* read permission */

Typedefs
typedef void(*	gsw_sig_t) (int sig)

Functions
void	gsw_init_semaphores (gsw_sema_t s)
	initialise the whiteboard semaphores More...

gsw_sema_t	gsw_setup_semaphores (int key)
	set up a semaphore array for the whiteboard More...

gu_simple_whiteboard_descriptor *	gsw_new_numbered_whiteboard (const char *name, int n)
	access a named whiteboard: this is the designated standard wb constructor for C programs that want to assign a whiteboard number (uses a different semaphore than the default) More...

gu_simple_whiteboard_descriptor *	gsw_new_custom_whiteboard (const char name, const char message_names[], int num_messages, int semaphore_magic_key)
	Access a named, custom whiteboard. More...

gu_simple_whiteboard_descriptor *	gswr_new_whiteboard (int i)
	access a remote named whiteboard: this is the designated constructore for C programs More...

gu_simple_whiteboard_descriptor *	gsw_new_whiteboard (const char *name)
	access a named whiteboard: this is the designated constructore for C programs More...

void	gsw_free_whiteboard (gu_simple_whiteboard_descriptor *wbd)
	free the given whiteboard descriptor More...

gu_simple_whiteboard_descriptor *	get_local_singleton_whiteboard (void)
	create a simple whiteboard for the local singleton wb pointer More...

gu_simple_whiteboard *	gsw_create (const char name, int fdp, bool *initial)
	create a simple whiteboard More...

void	gsw_free (gu_simple_whiteboard *wb, int fd)
	free the whiteboard More...

int	gsw_procure (gsw_sema_t sem, enum gsw_semaphores s)
	grab a whiteboard semaphore More...

int	gsw_vacate (gsw_sema_t sem, enum gsw_semaphores s)
	release a whiteboard semaphore More...

int	gsw_register_message_type (gu_simple_whiteboard_descriptor wbd, const char name)
	register a new whiteboard message type More...

int	gsw_offset_for_message_type (gu_simple_whiteboard_descriptor wbd, const char name)
	get the numerical index of a whiteboard message type More...

gu_simple_message *	gsw_current_message (gu_simple_whiteboard *wb, int i)
	get the current shared memory location for the given whiteboard message type i More...

gu_simple_message *	gsw_next_message (gu_simple_whiteboard *wb, int i)
	get the next shared memory location for the given whiteboard message type i More...

void	gsw_increment (gu_simple_whiteboard *wb, int i)
	get the next shared memory location for the given whiteboard message type i More...

void	gsw_increment_event_counter (gu_simple_whiteboard *wb, int i)
	add to a messages event counter on the wb More...

void	gsw_add_process (gu_simple_whiteboard_descriptor *wbd, const pid_t proc)
	add process for subscription signalling More...

void	gsw_remove_process (gu_simple_whiteboard_descriptor *wbd, const pid_t proc)
	remove process for subscription signalling More...

void	gsw_signal_subscribers (gu_simple_whiteboard *wb)
	signal all subscribing processes More...

void	gsw_add_wbd_signal_handler (gu_simple_whiteboard_descriptor *wbd)
	add subscription signal handler More...

void	gsw_remove_wbd_signal_handler (gu_simple_whiteboard_descriptor *wbd)
	remove subscription signal handler More...

Macro Definition Documentation

◆ __block [1/2]

#define __block _xblock

Definition at line 94 of file gusimplewhiteboard.c.

◆ __block [2/2]

#define __block __attribute__((__blocks__(byref)))

Definition at line 94 of file gusimplewhiteboard.c.

◆ _XOPEN_SOURCE

#define _XOPEN_SOURCE

Definition at line 74 of file gusimplewhiteboard.c.

◆ SEM_A

#define SEM_A 0200 /* alter permission */

Definition at line 120 of file gusimplewhiteboard.c.

◆ SEM_ERROR

#define SEM_ERROR -1

Definition at line 116 of file gusimplewhiteboard.c.

◆ SEM_R

#define SEM_R 0400 /* read permission */

Definition at line 121 of file gusimplewhiteboard.c.

◆ SEMAPHORE_MAGIC_KEY

#define SEMAPHORE_MAGIC_KEY 4242

Definition at line 115 of file gusimplewhiteboard.c.

◆ WHITEBOARD_MAGIC

#define WHITEBOARD_MAGIC 0xfeeda11deadbeef5ULL

Definition at line 114 of file gusimplewhiteboard.c.

Typedef Documentation

◆ gsw_sig_t

typedef void(* gsw_sig_t) (int sig)

Definition at line 603 of file gusimplewhiteboard.c.

Function Documentation

◆ get_local_singleton_whiteboard()

gu_simple_whiteboard_descriptor * get_local_singleton_whiteboard ( void )

create a simple whiteboard for the local singleton wb pointer

Definition at line 281 of file gusimplewhiteboard.c.

Referenced by whiteboard_watcher::whiteboard_watcher(), generic_whiteboard_object< object_type >::init(), and SimpleWhiteboardTestPlainC::setUp.

◆ gsw_add_process()

void gsw_add_process	(	gu_simple_whiteboard_descriptor *	wbd,
		const pid_t	proc
	)

add process for subscription signalling

subscribe a new process to receive signals

Definition at line 528 of file gusimplewhiteboard.c.

References gsw_procure(), GSW_SEM_PROC, GSW_TOTAL_PROCESSES, gsw_vacate(), gsw_simple_whiteboard_s::processes, gsw_whiteboard_s::sem, gsw_simple_whiteboard_s::subscribed, u_int16_t, and gsw_whiteboard_s::wb.

Referenced by whiteboard_watcher::subscribe(), and guWhiteboard::Whiteboard::subscribeToMessage().

◆ gsw_add_wbd_signal_handler()

void gsw_add_wbd_signal_handler ( gu_simple_whiteboard_descriptor * wbd )

add subscription signal handler

Definition at line 613 of file gusimplewhiteboard.c.

References gsw_procure(), GSW_SEM_PROC, and gsw_whiteboard_s::sem.

Referenced by whiteboard_watcher::subscribe(), and guWhiteboard::Whiteboard::subscribeToMessage().

◆ gsw_create()

gu_simple_whiteboard * gsw_create	(	const char *	name,
		int *	fdp,
		bool *	ini
	)

create a simple whiteboard

Parameters

name	name of the whiteboard
fdp	pointer to internal file descriptor storage (NULL if not needed)
ini	pointer to boolean recording wb initialisation

Definition at line 296 of file gusimplewhiteboard.c.

References GSW_DEFAULT_NAME, gsw_free(), GU_SIMPLE_WHITEBOARD_BUFSIZE, GU_SIMPLE_WHITEBOARD_VERSION, gsw_simple_whiteboard_s::magic, gsw_simple_whiteboard_s::version, and WHITEBOARD_MAGIC.

Referenced by gsw_new_custom_whiteboard().

◆ gsw_current_message()

gu_simple_message * gsw_current_message	(	gu_simple_whiteboard *	wb,
		int	i
	)

get the current shared memory location for the given whiteboard message type i

Definition at line 498 of file gusimplewhiteboard.c.

References GU_SIMPLE_WHITEBOARD_GENERATIONS, gsw_simple_whiteboard_s::indexes, gsw_simple_whiteboard_s::messages, and u_int8_t.

Referenced by generic_whiteboard_object< object_type >::get(), and guWhiteboard::Whiteboard::getMessage().

◆ gsw_free()

void gsw_free	(	gu_simple_whiteboard *	wb,
		int	fd
	)

free the whiteboard

Parameters

wb	whiteboard to free
fd	file descriptor to close (-1 to skip)

Definition at line 351 of file gusimplewhiteboard.c.

Referenced by gsw_create().

◆ gsw_free_whiteboard()

void gsw_free_whiteboard ( gu_simple_whiteboard_descriptor * wbd )

free the given whiteboard descriptor

Parameters

wbd	descriptor for the whiteboard

Definition at line 254 of file gusimplewhiteboard.c.

Referenced by guWhiteboard::Whiteboard::~Whiteboard(), whiteboard_watcher::~whiteboard_watcher(), and gsw_new_custom_whiteboard().

◆ gsw_increment()

void gsw_increment	(	gu_simple_whiteboard *	wb,
		int	i
	)

get the next shared memory location for the given whiteboard message type i

Definition at line 514 of file gusimplewhiteboard.c.

References GU_SIMPLE_WHITEBOARD_GENERATIONS, gsw_simple_whiteboard_s::indexes, and u_int8_t.

Referenced by guWhiteboard::Whiteboard::addMessage(), and generic_whiteboard_object< object_type >::set().

◆ gsw_increment_event_counter()

void gsw_increment_event_counter	(	gu_simple_whiteboard *	wb,
		int	i
	)

add to a messages event counter on the wb

Definition at line 521 of file gusimplewhiteboard.c.

References gsw_simple_whiteboard_s::event_counters.

Referenced by guWhiteboard::Whiteboard::addMessage(), and generic_whiteboard_object< object_type >::set().

◆ gsw_init_semaphores()

void gsw_init_semaphores ( gsw_sema_t sem )

initialise the whiteboard semaphores

Parameters

sem	whiteboard semaphore descriptor

Definition at line 136 of file gusimplewhiteboard.c.

References GSW_NUM_SEM.

Referenced by gsw_new_custom_whiteboard(), and gsw_setup_semaphores().

◆ gsw_new_custom_whiteboard()

gu_simple_whiteboard_descriptor * gsw_new_custom_whiteboard	(	const char *	name,
		const char *	message_names[],
		int	num_messages,
		int	semaphore_magic_key
	)

Access a named, custom whiteboard.

This is the designated custom wb constructor for C programs

Parameters

name	The name of the whiteboard to create/access
message_names	Array of `char *` containing the pre-defined (static) message names
num_messages	Number of messages in the `message_names` array
semaphore_magic_key	Semaphore magic key to use

Definition at line 206 of file gusimplewhiteboard.c.

References gsw_whiteboard_s::callback_queue, gsw_whiteboard_s::fd, gsw_create(), gsw_free_whiteboard(), gsw_init_semaphores(), gsw_register_message_type(), gsw_setup_semaphores(), gsw_whiteboard_s::sem, SEM_ERROR, and gsw_whiteboard_s::wb.

Referenced by gsw_new_numbered_whiteboard().

◆ gsw_new_numbered_whiteboard()

gu_simple_whiteboard_descriptor * gsw_new_numbered_whiteboard	(	const char *	name,
		int	num
	)

access a named whiteboard: this is the designated standard wb constructor for C programs that want to assign a whiteboard number (uses a different semaphore than the default)

Parameters