http.h

/*
 * libhttp - A HTTP (RFC 2616) library for C.
 */

#ifndef http_h
#define http_h

#include <stddef.h>

typedef struct http_stream_s http_stream;
typedef struct http_session_s http_session;
typedef struct http_message_s http_message;

typedef int (*http_stream_cb)(http_stream* stream, void* context);

enum http_error_codes {
  HTTP_ENOTIMPL         /* Not yet implemented. */
};

enum http_message_type {
  HTTP_MESSAGE_REQUEST,
  HTTP_MESSAGE_RESPONSE
};

/* Streams provide an interface for writing data to the socket
 * bound to a session. They are responsible for handling any
 * encoding/decoding of the data. Data will be written or read from
 * buffers supplied and returning number of bytes actually transferred.
 * Note: these methods may or may not block depending on the
 * underlying socket's mode.
 */
size_t http_stream_read(char* buffer, size_t size);
size_t http_stream_write(const char* buffer, size_t size);

/* A session represents a connection between a client and the server.
 * Create a socket connected to the server or accept incoming client
 * from listening socket. Initialize a new HTTP session using this socket.
 * Closing the session also closes the underlying socket.
 */
http_session* http_session_init(int sockfd);
void http_session_close(http_session* session);

/* Parsing of messages arriving from a session.
 * Clients will parse responses while servers parse requests.
 */
http_message* http_session_parse_request(http_session* session);
http_message* http_session_parse_response(http_session* session);

/* Compose a new message for sending with a session.
 * Clients will compose requests while servers compose responses.
 */
http_message* http_request(const char* method, const char* uri);
http_message* http_response(int status_code, const char* reason_phrase);

/* Append a new header to the message if a field with
 * this name does not yet exist. If it already exists then
 * the new value will be appended follow RFC2616 4.2 guidelines.
 */
void http_message_append_header(http_message* msg, const char* name, const char* value);

/* Type of message: request or response. */
int http_message_get_type(http_message* msg);

/* Set a stream callback for reading or writing the message body.
 * A parsed (incoming) message will read while a composed (outgoing)
 * message will be writing.
 */
void http_message_set_body_cb(http_message* msg, http_stream_cb cb, void* context);

/* Send a fully composed message with a session. */
int http_session_send_message(http_session* session, const http_message* msg);

#endif