extractor_ipc_gnu.c File Reference

IPC with plugin for GNU/POSIX systems. More...

#include "platform.h"
#include "extractor.h"
#include "extractor_datasource.h"
#include "extractor_logging.h"
#include "extractor_plugin_main.h"
#include "extractor_plugins.h"
#include "extractor_ipc.h"
#include <dirent.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/shm.h>
#include <signal.h>

Include dependency graph for extractor_ipc_gnu.c:

Go to the source code of this file.

Data Structures
struct	EXTRACTOR_SharedMemory
struct	EXTRACTOR_Channel

Functions
struct EXTRACTOR_SharedMemory *	EXTRACTOR_IPC_shared_memory_create_ (size_t size)
unsigned int	EXTRACTOR_IPC_shared_memory_change_rc_ (struct EXTRACTOR_SharedMemory *shm, int delta)
void	EXTRACTOR_IPC_shared_memory_destroy_ (struct EXTRACTOR_SharedMemory *shm)
ssize_t	EXTRACTOR_IPC_shared_memory_set_ (struct EXTRACTOR_SharedMemory *shm, struct EXTRACTOR_Datasource *ds, uint64_t off, size_t size)
uint64_t	EXTRACTOR_datasource_get_pos_ (struct EXTRACTOR_Datasource *ds)
struct EXTRACTOR_Channel *	EXTRACTOR_IPC_channel_create_ (struct EXTRACTOR_PluginList *plugin, struct EXTRACTOR_SharedMemory *shm)
void	EXTRACTOR_IPC_channel_destroy_ (struct EXTRACTOR_Channel *channel)
ssize_t	EXTRACTOR_IPC_channel_send_ (struct EXTRACTOR_Channel *channel, const void *data, size_t size)
int	EXTRACTOR_IPC_channel_recv_ (struct EXTRACTOR_Channel **channels, unsigned int num_channels, EXTRACTOR_ChannelMessageProcessor proc, void *proc_cls)

Detailed Description

IPC with plugin for GNU/POSIX systems.

Author

Christian Grothoff

Definition in file extractor_ipc_gnu.c.

Function Documentation

EXTRACTOR_datasource_get_pos_()

uint64_t EXTRACTOR_datasource_get_pos_

(

struct EXTRACTOR_Datasource *

ds

)

Query datasource for current position

Parameters

ds	data source to query

Returns

current position in the datasource or UINT_MAX on error

Definition at line 259 of file extractor_ipc_gnu.c.

EXTRACTOR_IPC_channel_create_()

struct EXTRACTOR_Channel* EXTRACTOR_IPC_channel_create_	(	struct EXTRACTOR_PluginList *	plugin,
		struct EXTRACTOR_SharedMemory *	shm
	)

Create a channel to communicate with a process wrapping the plugin of the given name. Starts the process as well.

Parameters

plugin	the plugin
shm	memory to share with the process

Returns

NULL on error, otherwise IPC channel

Definition at line 280 of file extractor_ipc_gnu.c.

EXTRACTOR_IPC_channel_destroy_()

void EXTRACTOR_IPC_channel_destroy_

(

struct EXTRACTOR_Channel *

channel

)

Destroy communication channel with a plugin/process. Also destroys the process.

Parameters

channel

channel to communicate with the plugin

Definition at line 399 of file extractor_ipc_gnu.c.

Referenced by EXTRACTOR_IPC_channel_create_(), and EXTRACTOR_IPC_channel_recv_().

EXTRACTOR_IPC_channel_recv_()

int EXTRACTOR_IPC_channel_recv_	(	struct EXTRACTOR_Channel **	channels,
		unsigned int	num_channels,
		EXTRACTOR_ChannelMessageProcessor	proc,
		void *	proc_cls
	)

Receive data from any of the given IPC channels (blocking). Wait for one of the plugins to reply. Selects on plugin output pipes, runs 'receive_reply' on each activated pipe until it gets a seek request or a done message. Called repeatedly by the user until all pipes are dry or broken.

Parameters

channels	array of channels, channels that break may be set to NULL
num_channels	length of the channels array
proc	function to call to process messages (may be called more than once)
proc_cls	closure for proc

Returns

-1 on error, 1 on success

Definition at line 467 of file extractor_ipc_gnu.c.

EXTRACTOR_IPC_channel_send_()

ssize_t EXTRACTOR_IPC_channel_send_	(	struct EXTRACTOR_Channel *	channel,
		const void *	data,
		size_t	size
	)

Send data via the given IPC channel (blocking).

Parameters

channel	channel to communicate with the plugin
buf	data to send
size	number of bytes in buf to send

Returns

-1 on error, number of bytes sent on success (never does partial writes)

Definition at line 428 of file extractor_ipc_gnu.c.

Referenced by EXTRACTOR_IPC_channel_create_().

EXTRACTOR_IPC_shared_memory_change_rc_()

unsigned int EXTRACTOR_IPC_shared_memory_change_rc_	(	struct EXTRACTOR_SharedMemory *	shm,
		int	delta
	)

Change the reference counter for this shm instance.

Parameters

shm	instance to update
delta	value to change RC by

Returns

new RC

Definition at line 196 of file extractor_ipc_gnu.c.

EXTRACTOR_IPC_shared_memory_create_()

struct EXTRACTOR_SharedMemory* EXTRACTOR_IPC_shared_memory_create_

(

size_t

size

)

Create a shared memory area.

Parameters

size	size of the shared area

Returns

NULL on error

Definition at line 134 of file extractor_ipc_gnu.c.

EXTRACTOR_IPC_shared_memory_destroy_()

void EXTRACTOR_IPC_shared_memory_destroy_

(

struct EXTRACTOR_SharedMemory *

shm

)

Destroy shared memory area.

Parameters

shm	memory area to destroy

Returns

NULL on error

Definition at line 211 of file extractor_ipc_gnu.c.

EXTRACTOR_IPC_shared_memory_set_()

ssize_t EXTRACTOR_IPC_shared_memory_set_	(	struct EXTRACTOR_SharedMemory *	shm,
		struct EXTRACTOR_Datasource *	ds,
		uint64_t	off,
		size_t	size
	)

Initialize shared memory area from data source.

Parameters

shm	memory area to initialize
ds	data source to use for initialization
off	offset to use in data source
size	number of bytes to copy

Returns

-1 on error, otherwise number of bytes copied

Definition at line 231 of file extractor_ipc_gnu.c.