HTTP client

Macros
#define	LWIP_HTTPC_HAVE_FILE_IO   0
#define	HTTP_DEFAULT_PORT   LWIP_IANA_PORT_HTTP

Typedefs
typedef enum ehttpc_result	httpc_result_t
typedef void(*	httpc_result_fn) (void *arg, httpc_result_t httpc_result, u32_t rx_content_len, u32_t srv_res, err_t err)
typedef err_t(*	httpc_headers_done_fn) (httpc_state_t *connection, void *arg, struct pbuf *hdr, u16_t hdr_len, u32_t content_len)

Enumerations
enum	ehttpc_result {   HTTPC_RESULT_OK = 0, HTTPC_RESULT_ERR_UNKNOWN = 1, HTTPC_RESULT_ERR_CONNECT = 2, HTTPC_RESULT_ERR_HOSTNAME = 3,   HTTPC_RESULT_ERR_CLOSED = 4, HTTPC_RESULT_ERR_TIMEOUT = 5, HTTPC_RESULT_ERR_SVR_RESP = 6, HTTPC_RESULT_ERR_MEM = 7,   HTTPC_RESULT_LOCAL_ABORT = 8, HTTPC_RESULT_ERR_CONTENT_LEN = 9 }

Functions
err_t	httpc_get_file (const ip_addr_t *server_addr, u16_t port, const char *uri, const httpc_connection_t *settings, altcp_recv_fn recv_fn, void *callback_arg, httpc_state_t **connection)
err_t	httpc_get_file_dns (const char *server_name, u16_t port, const char *uri, const httpc_connection_t *settings, altcp_recv_fn recv_fn, void *callback_arg, httpc_state_t **connection)

Detailed Description

Macro Definition Documentation

HTTP_DEFAULT_PORT

#define HTTP_DEFAULT_PORT   LWIP_IANA_PORT_HTTP

The default TCP port used for HTTP

LWIP_HTTPC_HAVE_FILE_IO

#define LWIP_HTTPC_HAVE_FILE_IO   0

HTTPC_HAVE_FILE_IO: define this to 1 to have functions dowloading directly to disk via fopen/fwrite. These functions are example implementations of the interface only.

Typedef Documentation

httpc_headers_done_fn

typedef err_t(* httpc_headers_done_fn) (httpc_state_t *connection, void *arg, struct pbuf *hdr, u16_t hdr_len, u32_t content_len)

Prototype of http client callback: called when the headers are received

Parameters

connection	http client connection
arg	argument specified when initiating the request
hdr	header pbuf(s) (may contain data also)
hdr_len	length of the heders in 'hdr'
content_len	content length as received in the headers (-1 if not received)

Returns

if != ERR_OK is returned, the connection is aborted

httpc_result_fn

typedef void(* httpc_result_fn) (void *arg, httpc_result_t httpc_result, u32_t rx_content_len, u32_t srv_res, err_t err)

Prototype of a http client callback function

Parameters

arg	argument specified when initiating the request
httpc_result	result of the http transfer (see enum httpc_result_t)
rx_content_len	number of bytes received (without headers)
srv_res	this contains the http status code received (if any)
err	an error returned by internal lwip functions, can help to specify the source of the error but must not necessarily be != ERR_OK

httpc_result_t

typedef enum ehttpc_result httpc_result_t

HTTP client result codes

Enumeration Type Documentation

ehttpc_result

enum ehttpc_result

HTTP client result codes

Enumerator
HTTPC_RESULT_OK	File successfully received
HTTPC_RESULT_ERR_UNKNOWN	Unknown error
HTTPC_RESULT_ERR_CONNECT	Connection to server failed
HTTPC_RESULT_ERR_HOSTNAME	Failed to resolve server hostname
HTTPC_RESULT_ERR_CLOSED	Connection unexpectedly closed by remote server
HTTPC_RESULT_ERR_TIMEOUT	Connection timed out (server didn't respond in time)
HTTPC_RESULT_ERR_SVR_RESP	Server responded with an error code
HTTPC_RESULT_ERR_MEM	Local memory error
HTTPC_RESULT_LOCAL_ABORT	Local abort
HTTPC_RESULT_ERR_CONTENT_LEN	Content length mismatch

Function Documentation

httpc_get_file()

err_t httpc_get_file	(	const ip_addr_t *	server_addr,
		u16_t	port,
		const char *	uri,
		const httpc_connection_t *	settings,
		altcp_recv_fn	recv_fn,
		void *	callback_arg,
		httpc_state_t **	connection
	)

HTTP client API: get a file by passing server IP address

Parameters

server_addr	IP address of the server to connect
port	tcp port of the server
uri	uri to get from the server, remember leading "/"!
settings	connection settings (callbacks, proxy, etc.)
recv_fn	the http body (not the headers) are passed to this callback
callback_arg	argument passed to all the callbacks
connection	retreives the connection handle (to match in callbacks)

Returns

ERR_OK if starting the request succeeds (callback_fn will be called later) or an error code

httpc_get_file_dns()

err_t httpc_get_file_dns	(	const char *	server_name,
		u16_t	port,
		const char *	uri,
		const httpc_connection_t *	settings,
		altcp_recv_fn	recv_fn,
		void *	callback_arg,
		httpc_state_t **	connection
	)

HTTP client API: get a file by passing server name as string (DNS name or IP address string)

Parameters

server_name	server name as string (DNS name or IP address string)
port	tcp port of the server
uri	uri to get from the server, remember leading "/"!
settings	connection settings (callbacks, proxy, etc.)
recv_fn	the http body (not the headers) are passed to this callback
callback_arg	argument passed to all the callbacks
connection	retreives the connection handle (to match in callbacks)

Returns

ERR_OK if starting the request succeeds (callback_fn will be called later) or an error code