select() loop abstraction More...

Files
file	select.h
	libmnl integration

file	select.c
	select filedescriptor handling.

Data Structures
struct	osmo_fd
	Structure representing a file dsecriptor. More...

struct	osmo_signalfd

struct	poll_state

Macros
#define	OSMO_FD_READ 0x0001
	Indicate interest in reading from the file descriptor. More...

#define	OSMO_FD_WRITE 0x0002
	Indicate interest in writing to the file descriptor. More...

#define	OSMO_FD_EXCEPT 0x0004
	Indicate interest in exceptions from the file descriptor. More...

#define	OSMO_FD_MASK 0xFFFF
	Used as when_mask in osmo_fd_update_when() More...

#define	BSC_FD_READ OSMO_FD_READ

#define	BSC_FD_WRITE OSMO_FD_WRITE

#define	BSC_FD_EXCEPT OSMO_FD_EXCEPT

Typedefs
typedef void	osmo_signalfd_cb(struct osmo_signalfd osfd, const struct signalfd_siginfo fdsi)

Functions
void	osmo_fd_setup (struct osmo_fd ofd, int fd, unsigned int when, int(cb)(struct osmo_fd fd, unsigned int what), void data, unsigned int priv_nr)
	Set up an osmo-fd. More...

void	osmo_fd_update_when (struct osmo_fd *ofd, unsigned int when_mask, unsigned int when)
	Update the 'when' field of osmo_fd. More...

static void	osmo_fd_read_enable (struct osmo_fd *ofd)

static void	osmo_fd_read_disable (struct osmo_fd *ofd)

static void	osmo_fd_write_enable (struct osmo_fd *ofd)

static void	osmo_fd_write_disable (struct osmo_fd *ofd)

bool	osmo_fd_is_registered (struct osmo_fd *fd)
	Check if a file descriptor is already registered. More...

int	osmo_fd_register (struct osmo_fd *fd)
	Register a new file descriptor with select loop abstraction. More...

void	osmo_fd_unregister (struct osmo_fd *fd)
	Unregister a file descriptor from select loop abstraction. More...

void	osmo_fd_close (struct osmo_fd *fd)
	Close a file descriptor, mark it as closed + unregister from select loop abstraction. More...

int	osmo_select_main (int polling)
	select main loop integration More...

int	osmo_select_main_ctx (int polling)
	select main loop integration with temporary select-dispatch talloc context More...

void	osmo_select_init (void)
	initialize the osmocom select abstraction for the current thread More...

struct osmo_fd *	osmo_fd_get_by_fd (int fd)
	find an osmo_fd based on the integer fd More...

int	osmo_fd_fill_fds (void _rset, void _wset, void *_eset)
	Populate the fd_sets and return the highest fd number. More...

int	osmo_fd_disp_fds (void readset, void writeset, void *exceptset)

int	osmo_timerfd_disable (struct osmo_fd *ofd)
	disable the osmocom-wrapped timerfd More...

int	osmo_timerfd_schedule (struct osmo_fd ofd, const struct timespec first, const struct timespec *interval)
	schedule the osmocom-wrapped timerfd to occur first at first, then periodically at interval More...

int	osmo_timerfd_setup (struct osmo_fd ofd, int(cb)(struct osmo_fd , unsigned int), void data)
	setup osmocom-wrapped timerfd More...

struct osmo_signalfd *	osmo_signalfd_setup (void ctx, sigset_t set, osmo_signalfd_cb cb, void *data)
	create a signalfd and register it with osmocom select loop. More...

void	osmo_select_shutdown_request ()
	Request osmo_select_* to only service pending OSMO_FD_WRITE requests. More...

int	osmo_select_shutdown_requested ()
	Return the number of times osmo_select_shutdown_request() was called before. More...

bool	osmo_select_shutdown_done ()
	Return true after osmo_select_shutdown_requested() was called, and after an osmo_select poll loop found no more pending OSMO_FD_WRITE on any registered socket. More...

static unsigned int	poll_fill_fds (void)

static int	poll_disp_fds (unsigned int n_fd)

static int	_osmo_select_main (int polling)

static	__attribute__ ((constructor))

static int	signalfd_callback (struct osmo_fd *ofd, unsigned int what)

Variables
static __thread int	maxfd = 0

static __thread struct llist_head	osmo_fds

static __thread int	unregistered_count

static __thread struct poll_state	g_poll

static int	_osmo_select_shutdown_requested = 0
	See osmo_select_shutdown_request() More...

static bool	_osmo_select_shutdown_done = false
	See osmo_select_shutdown_request() More...

Detailed Description

select() loop abstraction

Macro Definition Documentation

◆ BSC_FD_EXCEPT

#define BSC_FD_EXCEPT OSMO_FD_EXCEPT

◆ BSC_FD_READ

#define BSC_FD_READ OSMO_FD_READ

◆ BSC_FD_WRITE

#define BSC_FD_WRITE OSMO_FD_WRITE

◆ OSMO_FD_EXCEPT

#define OSMO_FD_EXCEPT 0x0004

Indicate interest in exceptions from the file descriptor.

◆ OSMO_FD_MASK

#define OSMO_FD_MASK 0xFFFF

Used as when_mask in osmo_fd_update_when()

◆ OSMO_FD_READ

#define OSMO_FD_READ 0x0001

Indicate interest in reading from the file descriptor.

◆ OSMO_FD_WRITE

#define OSMO_FD_WRITE 0x0002

Indicate interest in writing to the file descriptor.

Typedef Documentation

◆ osmo_signalfd_cb

typedef void osmo_signalfd_cb(struct osmo_signalfd *osfd, const struct signalfd_siginfo *fdsi)

Function Documentation

◆ attribute()

static __attribute__ ( (constructor) )

static

References osmo_select_init().

◆ _osmo_select_main()

static int _osmo_select_main ( int polling )

static

References _osmo_select_shutdown_requested, g_poll, OSMO_ASSERT, osmo_ctx, osmo_timers_nearest_ms(), osmo_timers_prepare(), osmo_timers_update(), poll_state::poll, poll_disp_fds(), poll_fill_fds(), and osmo_talloc_contexts::select.

Referenced by osmo_select_main(), and osmo_select_main_ctx().

◆ osmo_fd_close()

void osmo_fd_close ( struct osmo_fd * fd )

Close a file descriptor, mark it as closed + unregister from select loop abstraction.

Parameters

[in] fd osmocom file descriptor to be unregistered + closed

If fd is registered, we unregister it from the select() loop abstraction. We then close the fd and set it to -1, as well as unsetting any 'when' flags

References osmo_fd::fd, osmo_fd_is_registered(), osmo_fd_unregister(), and osmo_fd::when.

Referenced by osmo_it_q_alloc(), and osmo_it_q_destroy().

◆ osmo_fd_disp_fds()

int osmo_fd_disp_fds	(	void *	readset,
		void *	writeset,
		void *	exceptset
	)

inline

References osmo_fd::cb, osmo_fd::fd, flags, list, llist_for_each_entry_safe, log_reset_context(), OSMO_FD_EXCEPT, OSMO_FD_READ, OSMO_FD_WRITE, osmo_fds, and unregistered_count.

◆ osmo_fd_fill_fds()

int osmo_fd_fill_fds	(	void *	_rset,
		void *	_wset,
		void *	_eset
	)

inline

Populate the fd_sets and return the highest fd number.

Parameters

[in]	_rset	The readfds to populate
[in]	_wset	The wrtiefds to populate
[in]	_eset	The errorfds to populate

Returns: The highest file descriptor seen or 0 on an empty list

References osmo_fd::fd, list, llist_for_each_entry, OSMO_FD_EXCEPT, OSMO_FD_READ, OSMO_FD_WRITE, osmo_fds, and osmo_fd::when.

◆ osmo_fd_get_by_fd()

struct osmo_fd * osmo_fd_get_by_fd ( int fd )

find an osmo_fd based on the integer fd

Parameters

[in] fd file descriptor to use as search key

Returns: osmo_fd for fd; NULL in case it doesn't exist

References osmo_fd::fd, list, llist_for_each_entry, and osmo_fds.

Referenced by poll_disp_fds().

◆ osmo_fd_is_registered()

bool osmo_fd_is_registered ( struct osmo_fd * fd )

Check if a file descriptor is already registered.

Parameters

[in] fd osmocom file descriptor to be checked

Returns: true if registered; otherwise false

References osmo_fd::fd, list, llist_for_each_entry, and osmo_fds.

Referenced by osmo_fd_close(), and osmo_fd_register().

◆ osmo_fd_read_disable()

static void osmo_fd_read_disable ( struct osmo_fd * ofd )

inlinestatic

References OSMO_FD_READ, and osmo_fd_update_when().

◆ osmo_fd_read_enable()

static void osmo_fd_read_enable ( struct osmo_fd * ofd )

inlinestatic

References OSMO_FD_MASK, OSMO_FD_READ, and osmo_fd_update_when().

◆ osmo_fd_register()

int osmo_fd_register ( struct osmo_fd * fd )

Register a new file descriptor with select loop abstraction.

Parameters

[in] fd osmocom file descriptor to be registered

Returns: 0 on success; negative in case of error

References osmo_fd::fd, flags, g_poll, osmo_fd::list, llist_add_tail(), maxfd, poll_state::num_registered, osmo_fd_is_registered(), osmo_fds, OTC_GLOBAL, poll_state::poll, and poll_state::poll_size.

Referenced by gsmtap_source_add_sink(), gsmtap_source_init(), log_target_create_file(), log_target_file_reopen(), log_target_file_switch_to_wqueue(), osmo_fd_init_ofd(), osmo_mnl_init(), osmo_signalfd_setup(), and osmo_timerfd_setup().

◆ osmo_fd_setup()

void osmo_fd_setup	(	struct osmo_fd *	ofd,
		int	fd,
		unsigned int	when,
		int()(struct osmo_fd fd, unsigned int what)	cb,
		void *	data,
		unsigned int	priv_nr
	)

Set up an osmo-fd.

Will not register it.

Parameters

[in,out]	ofd	Osmo FD to be set-up
[in]	fd	OS-level file descriptor number
[in]	when	bit-mask of OSMO_FD_{READ,WRITE,EXECEPT}
[in]	cb	Call-back function to be called
[in]	data	Private context pointer
[in]	priv_nr	Private number

References osmo_fd::cb, data, osmo_fd::data, osmo_fd::fd, osmo_fd::priv_nr, and osmo_fd::when.

Referenced by osmo_it_q_alloc(), osmo_mnl_init(), and osmo_signalfd_setup().

◆ osmo_fd_unregister()

void osmo_fd_unregister ( struct osmo_fd * fd )

Unregister a file descriptor from select loop abstraction.

Parameters

[in] fd osmocom file descriptor to be unregistered

References g_poll, osmo_fd::list, llist_del(), poll_state::num_registered, osmo_stats_tcp_osmo_fd_unregister(), and unregistered_count.

Referenced by gsmtap_source_free(), log_target_destroy(), log_target_file_reopen(), log_target_file_switch_to_stream(), osmo_fd_close(), osmo_mnl_destroy(), osmo_timerfd_setup(), and signalfd_callback().

◆ osmo_fd_update_when()

void osmo_fd_update_when	(	struct osmo_fd *	ofd,
		unsigned int	when_mask,
		unsigned int	when
	)

Update the 'when' field of osmo_fd.

"ofd->when = (ofd->when & when_mask) | when". Use this function instead of directly modifying ofd->when, as the latter will be removed soon.

References osmo_fd::when.

Referenced by osmo_fd_read_disable(), osmo_fd_read_enable(), osmo_fd_write_disable(), and osmo_fd_write_enable().

◆ osmo_fd_write_disable()

static void osmo_fd_write_disable ( struct osmo_fd * ofd )

inlinestatic

References osmo_fd_update_when(), and OSMO_FD_WRITE.

◆ osmo_fd_write_enable()

static void osmo_fd_write_enable ( struct osmo_fd * ofd )

inlinestatic

References OSMO_FD_MASK, osmo_fd_update_when(), and OSMO_FD_WRITE.

◆ osmo_select_init()

void osmo_select_init ( void )

initialize the osmocom select abstraction for the current thread

References INIT_LLIST_HEAD, and osmo_fds.

Referenced by __attribute__().

◆ osmo_select_main()

int osmo_select_main ( int polling )

select main loop integration

Parameters

[in] polling should we pollonly (1) or block on select (0)

Returns: 0 if no fd handled; 1 if fd handled; negative in case of error

References _osmo_select_main(), osmo_ctx, osmo_panic(), and osmo_talloc_contexts::select.

◆ osmo_select_main_ctx()

int osmo_select_main_ctx ( int polling )

select main loop integration with temporary select-dispatch talloc context

Parameters

[in] polling should we pollonly (1) or block on select (0)

Returns: 0 if no fd handled; 1 if fd handled; negative in case of error

References _osmo_select_main(), osmo_ctx, and osmo_talloc_contexts::select.

◆ osmo_select_shutdown_done()

bool osmo_select_shutdown_done ( )

Return true after osmo_select_shutdown_requested() was called, and after an osmo_select poll loop found no more pending OSMO_FD_WRITE on any registered socket.

References _osmo_select_shutdown_done.

◆ osmo_select_shutdown_request()

void osmo_select_shutdown_request ( )

Request osmo_select_* to only service pending OSMO_FD_WRITE requests.

Once all writes are done, osmo_select_shutdown_done() returns true. This allows for example to send all outbound packets before terminating the process.

Usage example:

static void signal_handler(int signum) { fprintf(stdout, "signal %u received\n", signum);

switch (signum) { case SIGINT: case SIGTERM: // If the user hits Ctrl-C the third time, just terminate immediately. if (osmo_select_shutdown_requested() >= 2) exit(-1); // Request write-only mode in osmo_select_main_ctx() osmo_select_shutdown_request(); break; [...] }

main() { signal(SIGINT, &signal_handler); signal(SIGTERM, &signal_handler);

[...]

// After the signal_handler issued osmo_select_shutdown_request(), osmo_select_shutdown_done() returns true // as soon as all write queues are empty. while (!osmo_select_shutdown_done()) { osmo_select_main_ctx(0); } }

References _osmo_select_shutdown_requested.

◆ osmo_select_shutdown_requested()

int osmo_select_shutdown_requested ( )

Return the number of times osmo_select_shutdown_request() was called before.

References _osmo_select_shutdown_requested.

◆ osmo_signalfd_setup()

struct osmo_signalfd * osmo_signalfd_setup	(	void *	ctx,
		sigset_t	set,
		osmo_signalfd_cb *	cb,
		void *	data
	)

create a signalfd and register it with osmocom select loop.

Parameters

[in]	ctx	talloc context from which osmo_signalfd is to be allocated
[in]	set	of signals to be accept via this file descriptor
[in]	cb	call-back function to be called for each arriving signal
[in]	data	opaque user-provided data to pass to callback

Returns: pointer to newly-allocated + registered osmo_signalfd; NULL on error

References osmo_signalfd::cb, data, osmo_signalfd::data, osmo_signalfd::ofd, OSMO_FD_READ, osmo_fd_register(), osmo_fd_setup(), signalfd_callback(), and osmo_signalfd::sigset.

◆ osmo_timerfd_disable()

int osmo_timerfd_disable ( struct osmo_fd * ofd )

disable the osmocom-wrapped timerfd

References osmo_fd::fd.

Referenced by start_timer().

◆ osmo_timerfd_schedule()

int osmo_timerfd_schedule	(	struct osmo_fd *	ofd,
		const struct timespec *	first,
		const struct timespec *	interval
	)

schedule the osmocom-wrapped timerfd to occur first at first, then periodically at interval

Parameters

[in]	ofd	Osmocom wrapped timerfd
[in]	first	Relative time at which the timer should first execute (NULL = interval)
[in]	interval	Time interval at which subsequent timer shall fire

Returns: 0 on success; negative on error

References osmo_fd::fd.

Referenced by start_timer().

◆ osmo_timerfd_setup()

int osmo_timerfd_setup	(	struct osmo_fd *	ofd,
		int()(struct osmo_fd , unsigned int)	cb,
		void *	data
	)

setup osmocom-wrapped timerfd

Parameters

[in,out]	ofd	Osmocom-wrapped timerfd on which to operate
[in]	cb	Call-back function called when timerfd becomes readable
[in]	data	Opaque data to be passed on to call-back