usock-udp (Unix Socket UDP)

Header: udo/usock-udp.h

Table of contents (click to go)

Macros

Enums

Unions

Structs

1. udo_usock_udp

2. udo_usock_udp_server_create_info

3. udo_usock_udp_client_create_info

Functions

1. udo_usock_udp_server_create()

2. udo_usock_udp_server_recv_data()

3. udo_usock_udp_client_create()

4. udo_usock_udp_client_send_data()

5. udo_usock_udp_get_fd()

6. udo_usock_udp_get_unix_path()

7. udo_usock_udp_destroy()

8. udo_usock_udp_get_sizeof()

9. udo_usock_udp_recv_data()

10. udo_usock_udp_send_data()

API Documentation

udo_usock_udp (private)

Structure defining UDO Unix Socket UDP context.

struct udo_usock_udp

struct udo_log_error_struct err;

bool free;

int fd;

struct sockaddr_un addr;

struct sockaddr_un saddr;

err

Stores information about the error that occured

for the given context and may later be retrieved

by caller.

free

If structure allocated with calloc(3) member will be

set to true so that, we know to call free(3) when

destroying the context.

fd

File descriptor to the open UDP socket

addr

Stores byte information about the UDP unix domain

socket context. Is used for client and server bind(2).

saddr

Stores byte information about the UDP unix domain

socket context. Is used for client connect(2).

---

udo_usock_udp_server_create_info

Structure passed to udo_usock_udp_server_create()

used to define how to create the server.

struct udo_usock_udp_server_create_info

const char *unix_path;

unix_path

Absolute path to unix domain socket

to recvfrom(2) data with.

udo_usock_udp_server_create

struct udo_usock_udp *udo_usock_udp_server_create(struct udo_usock_udp *usock, const void *usock_info);

Creates a socket that may be utilized for server socket operations.

Param	Decription
usock	May be NULL or a pointer to a struct udo_usock_udp. If NULL memory will be allocated and return to caller. If not NULL address passed will be used to store the newly created struct udo_usock_udp context.
usock_info	Implementation uses a pointer to a struct udo_usock_udp_server_create_info.

Returns:

on success: Pointer to a struct udo_usock_udp

on failure: NULL

---

udo_usock_udp_server_recv_data

ssize_t udo_usock_udp_server_recv_data(struct udo_usock_udp *usock, void *data, const size_t size, struct sockaddr_un *addr, const void *usock_info);

Receive data from server socket file descriptor.

Param	Decription
usock	Pointer to a struct udo_usock_udp context.
data	Pointer to buffer to store data received from a socket.
size	Size of data to receive from a socket.
addr	Pointer to struct sockaddr_un which stores the address information of the socket that data was received from.
usock_info	Reserved for future usage. For now used to set the flag argument of recvfrom(2).

Returns:

on success: Amount of bytes received

on failure: # < 0

---

udo_usock_udp_client_create_info

Structure passed to udo_usock_udp_client_create()

used to define how to create the client.

struct udo_usock_udp_client_create_info

const char *srv_unix_path;

const char *cli_unix_path;

srv_unix_path

Absolute path to unix domain socket to write to.

cli_unix_path

Absolute path to unix domain socket to read with.

Largely so the srv_unix_path knows the path to

the client when leveraging the recvfrom(2) call.

udo_usock_udp_client_create

struct udo_usock_udp *udo_usock_udp_client_create(struct udo_usock_udp *usock, const void *usock_info);

Creates a socket that may be utilized for client socket operations.

Fliters client socket to allow sending data without passing a

struct sockaddr_un to sendto(2).

NOTE: Due to filtering approach caller must first create

the server via udo_usock_udp_server_create(). So, that

the connect(2) call doesn’t fail.

Param	Decription
usock	May be NULL or a pointer to a struct udo_usock_udp. If NULL memory will be allocated and return to caller. If not NULL address passed will be used to store the newly created struct udo_usock_udp context.
usock_info	Implementation uses a pointer to a struct udo_usock_udp_client_create_info.

Returns:

on success: Pointer to a struct udo_usock_udp

on failure: NULL

---

udo_usock_udp_client_send_data

ssize_t udo_usock_udp_client_send_data(struct udo_usock_udp *usock, const void *data, const size_t size, const void *usock_info);

Send data to client socket address provided via

call to udo_usock_udp_client_create().

Param	Must pass a pointer to a struct udo_usock_udp.
data	Pointer to buffer to send through socket.
size	Size of data to send through socket.
usock_info	Reserved for future usage. For now used to set the flag argument of sendto(2).

Returns:

on success: Amount of bytes sent

on failure: # < 0

---

udo_usock_udp_get_fd

int udo_usock_udp_get_fd(struct udo_usock_udp *usock);

Acquire socket file descriptor associated with

struct udo_usock_udp context.

Param	Decription
usock	Must pass a pointer to a struct udo_usock_udp.

Returns:

on success: Unix domain socket file descriptor

on failure: -1

---

udo_usock_udp_get_unix_path

const char *udo_usock_udp_get_unix_path(struct udo_usock_udp *usock);

Acquire textual path to unix domain socket file in string

format associated with struct udo_usock_udp context.

Param	Decription
usock	Must pass a pointer to a struct udo_usock_udp.

Returns:

on success: Textual path to unix domain socket

on failure: NULL

---

udo_usock_udp_destroy

void udo_usock_udp_destroy(struct udo_usock_udp *usock);

Frees any allocated memory and closes FD’s (if open) created after

udo_usock_udp_server_create() or udo_usock_udp_client_create() call.

Param	Decription
usock	Pointer to a valid struct udo_usock_udp.

---

udo_usock_udp_get_sizeof

int udo_usock_udp_get_sizeof(void);

Returns size of the internal structure. So,

if caller decides to allocate memory outside

of API interface they know the exact amount

of bytes.

Returns:

on success: sizeof(struct udo_usock_udp)

on failure: sizeof(struct udo_usock_udp)

---

udo_usock_udp_recv_data

ssize_t udo_usock_udp_recv_data(const int sock_fd, void *data, const size_t size, struct sockaddr_un *addr, const void *usock_info);

Receive data from socket file descriptor.

Param	Decription
sock_fd	Socket file descriptor to receive data from.
data	Pointer to buffer to store data received from a socket.
size	Size of data to receive from a socket.
addr	Pointer to struct sockaddr_un which stores the address information of the socket that data was received from.
usock_info	Reserved for future usage. For now used to set the flag argument of recvfrom(2).

Returns:

on success: Amount of bytes received

on failure: # < 0

---

udo_usock_udp_send_data

ssize_t udo_usock_udp_send_data(const int sock_fd, const void *data, const size_t size, const struct sockaddr_un *addr, const void *usock_info);

Send data to socket file descriptor.

Param	Decription
sock_fd	Socket file descriptor to send data to.
data	Pointer to buffer to send through socket.
size	Size of data to send through socket.
addr	Pointer to struct sockaddr_un which stores the address information of a socket that data will be sent to.
usock_info	Reserved for future usage. For now used to set the flag argument of sendto(2).

Returns:

on success: Amount of bytes sent

on failure: # < 0

---