ipc.c File Reference

Everything required to parse, interpret and respond to messages that are sent over IPC. More...

#include <sys/socket.h>
#include <sys/un.h>
#include <stdbool.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include "client.h"
#include "helper.h"
#include "howm.h"
#include "ipc.h"
#include "layout.h"
#include "monitor.h"
#include "op.h"
#include "scratchpad.h"
#include "types.h"
#include "workspace.h"

Macros
#define	CALL_INT(func, arg, lower, upper)
#define	CALL_WORKSPACE(func, arg, lower, upper)
#define	SET_INT(opt, arg, lower, upper)
#define	SET_BOOL(opt, arg)
#define	SET_COLOUR(opt, arg)

Enumerations
enum	msg_type { MSG_FUNCTION = 1, MSG_CONFIG }

Functions
static char **	ipc_process_args (char *msg, int len, int *err)
	Accepts a char array and convert it into an array of strings. More...
static int	ipc_arg_to_int (char *arg, int *err, int lower, int upper)
	Convert a numerical string into a decimal value, such as "12" becoming 12. More...
static int	ipc_process_function (char **args)
	Receive a char array from a UNIX socket and subsequently call a function, passing the args from within msg. More...
static int	ipc_process_config (char **args)
	Process a config message. If the config option isn't recognised, set err to IPC_ERR_NO_CONFIG. More...
static bool	ipc_arg_to_bool (char *arg, int *err)
	Convert an argument to a boolean. More...
int	ipc_init (void)
	Open a socket and return it. More...
void	ipc_cleanup (void)
	Delete the UNIX socket file. More...
int	ipc_process (char *msg, int len)
	Process a message depending on its type - a config message or a function call message. More...

Detailed Description

Everything required to parse, interpret and respond to messages that are sent over IPC.

Author

Harvey Hunt

Date

2015

Macro Definition Documentation

#define CALL_INT	(		func,
			arg,
			lower,
			upper
	)

Value:

do { \
                i = ipc_arg_to_int(arg, &err, lower, upper); \
                if (err == IPC_ERR_NONE) \
                        func(i); \
        } while (0)

#define CALL_WORKSPACE	(		func,
			arg,
			lower,
			upper
	)

Value:

do { \
                i = ipc_arg_to_int(arg, &err, lower, upper); \
                if (err == IPC_ERR_NONE) { \
                        func(index_to_workspace(mon, i)); \
                } \
        } while (0)

#define SET_BOOL	(		opt,
			arg
	)

Value:

do { \
                b = ipc_arg_to_bool(arg, &err); \
                        if (err == IPC_ERR_NONE) \
                                opt = b; \
        } while (0)

#define SET_COLOUR	(		opt,
			arg
	)

Value:

do { \
                if (strlen(arg) > 7) \
                        return IPC_ERR_ARG_TOO_LARGE; \
                else if (strlen(arg) < 7) \
                        return IPC_ERR_ARG_TOO_SMALL; \
                opt = get_colour(arg); \
        } while (0)

#define SET_INT	(		opt,
			arg,
			lower,
			upper
	)

Value:

do { \
                i = ipc_arg_to_int(arg, &err, lower, upper); \
                        if (err == IPC_ERR_NONE) \
                                opt = i; \
        } while (0)

Enumeration Type Documentation

enum msg_type

Enumerator
MSG_FUNCTION
MSG_CONFIG

Function Documentation

static bool ipc_arg_to_bool ( char *  arg, int *  err  )

static

Convert an argument to a boolean.

t and 1 are considered true, f and 0 are considered false.

Parameters

arg	A string containing the argument.
err	Where an error code should be stored.

Returns

A boolean, depending on whether the argument was true or false.

static int ipc_arg_to_int ( char *  arg, int *  err, int  lower, int  upper  )

static

Convert a numerical string into a decimal value, such as "12" becoming 12.

Minus signs are handled. It is assumed that a two digit number won't start with a zero. Args with more than two digits will not be accepted, nor will args that aren't numerical.

Parameters

arg	The string to be converted.
err	Where errors are reported.
lower	The lower bound for the returned value. Note: This is inclusive
upper	The upper bound for the returned value. Note: This is inclusive

Returns

The decimal representation of arg.

void ipc_cleanup

(

void

)

Delete the UNIX socket file.

int ipc_init

(

void

)

Open a socket and return it.

If a socket path is defined in the env variable defined as ENV_SOCK_VAR then use that - else use DEF_SOCK_PATH.

Returns

A socket file descriptor.

int ipc_process	(	char *	msg,
		int	len
	)

Process a message depending on its type - a config message or a function call message.

Parameters

msg	A buffer containing the message sent by cottage.
len	The length of the message.

Returns

An error code resulting from processing msg.

static char ** ipc_process_args ( char *  msg, int  len, int *  err  )

static

Accepts a char array and convert it into an array of strings.

msg is split into strings (delimited by a null character) and placed in an array. err is set with a corresponding error (such as args too few args), or nothing.

XXX: args must be freed by the caller.

Parameters

msg	A char array that is read from a UNIX socket.
len	The length of data in msg.
err	Where any errors will be stored.

Returns

A pointer to an array of strings, each one representing an argument that has been passed over a UNIX socket.

static int ipc_process_config ( char **  args )

static

Process a config message. If the config option isn't recognised, set err to IPC_ERR_NO_CONFIG.

Parameters

args	An array of strings representing the args.

Returns

err containing the error (or lack of) that has occurred.

static int ipc_process_function ( char **  args )

static

Receive a char array from a UNIX socket and subsequently call a function, passing the args from within msg.

Parameters

args	The args (as strings).

Returns

The error code, as set by this function itself or those that it calls.