http_server.c

/***============================================================================================================================
 * Depedencies inclusion
 * Necessary dependencies should be declared here. Header file should contain as little dependecies declarations as possible
 *=============================================================================================================================*/
 
#include "http_server.h"
#include "altcp.h"
#include "cmsis_os.h"
#include <string.h>
 
 
/***============================================================================================================================
 * Private functions definitions
 * These functions are only accessible from within the file's scope
 *=============================================================================================================================*/
 
static void _http_close(struct altcp_pcb *pcb, http_request_s *req){
 
    altcp_arg(pcb, NULL);
    altcp_recv(pcb, NULL);
    altcp_sent(pcb, NULL);
    altcp_poll(pcb, NULL, 0);
    altcp_err(pcb,  NULL);
 
    if(req != NULL){
        http_request_free(req);
    }
 
    altcp_close(pcb);
 
}
 
static err_t _http_send(struct altcp_pcb *pcb, http_request_s *req){
 
    err_t err = ERR_OK;
 
    uint16_t max_len, chunk_len = LWIP_MIN(http_response_get_bytes_left(req->res), 0xffff);
 
    if(chunk_len <= 0){
        return ERR_OK;
    }
 
    max_len = altcp_sndbuf(pcb);
    if (max_len < chunk_len) {
        chunk_len = max_len;
    }
 
    do {
        err = altcp_write(pcb, req->res->data_ptr + req->res->data_ptr_index, chunk_len, 0);
        if (err == ERR_MEM) {
            if ((altcp_sndbuf(pcb) == 0) || (altcp_sndqueuelen(pcb) >= TCP_SND_QUEUELEN)) {
                chunk_len = 1;
            } else {
                chunk_len /= 2;
            }
        }
    } while ((err == ERR_MEM) && (chunk_len > 1));
 
    if (err == ERR_OK) {
        req->res->data_ptr_index += chunk_len;
    }
 
    if(!http_response_get_bytes_left(req->res)){
        _http_close(pcb, req);
    }
 
    return err;
 
}
 
 
static err_t _http_receive(void *arg, struct altcp_pcb *pcb,struct pbuf *p, err_t err){
 
    http_request_s *req = arg;
 
    if(err != ERR_OK || p == NULL || req == NULL){
        if(p != NULL){ altcp_recved(pcb, p->tot_len); pbuf_free(p); }
        _http_close(pcb, req);
    }else{
        altcp_recved(pcb, p->tot_len);
        if(http_request_parse(req, p)){
            pbuf_free(p);
            req->router(req);
            _http_send(pcb, req);
        }else{
            pbuf_free(p);
            _http_close(pcb, req);
        }
    }
 
    return ERR_OK;
 
}
 
static err_t _http_sent(void *arg, struct altcp_pcb *pcb, uint16_t len){
    http_request_s *req = arg;
    if(req != NULL){
        _http_send(pcb, req);
    }
    return ERR_OK;
}
 
static err_t _http_poll(void *arg, struct altcp_pcb *pcb){
 
    http_request_s *req = arg;
 
      if (req == NULL) {
        _http_close(pcb, NULL);
        return ERR_OK;
      } else {
        req->retry_count++;
        if (req->retry_count == 10) {
          _http_close(pcb, req);
          return ERR_OK;
        }
        if (req->res->data_ptr != NULL) {
          if (_http_send(pcb, req)) {
            altcp_output(pcb);
          }
        }
      }
 
      return ERR_OK;
 
}
 
static void _http_error(void *arg, err_t err){
    http_request_s *req = arg;
    if (req != NULL) {
        http_request_free(req);
    }
}
 
static err_t _http_accept(void *arg, struct altcp_pcb *pcb, err_t err){
 
    http_server_s *server = arg;
 
    if(err != ERR_OK || pcb == NULL){
        err = ERR_VAL;
    }else{
 
        http_request_s *req = http_request_new(server->router);
 
        if(req == NULL){
            return ERR_MEM;
        }
 
        altcp_arg(pcb, req);
        altcp_recv(pcb, _http_receive);
        altcp_sent(pcb, _http_sent);
        altcp_poll(pcb, _http_poll, 4);
        altcp_err(pcb, _http_error);
 
    }
 
    return err;
 
}
 
static void _http_prepare_pcb(http_server_s *server){
 
    struct altcp_pcb *pcb;
 
    pcb = altcp_tcp_new_ip_type(IPADDR_TYPE_ANY);
 
    altcp_bind(pcb, IP_ANY_TYPE, server->port);
 
    pcb = altcp_listen(pcb);
 
    server->pcb = pcb;
 
    altcp_setprio(pcb, 1);
    altcp_arg(pcb, server);
    altcp_accept(pcb, _http_accept);
 
}
 
 
/***============================================================================================================================
 * Public functions definitions
 * These functions can be accessed outside of the file's scope
 * @see HTTP_server.h for declarations
 *=============================================================================================================================*/
 
http_server_s *http_server_init(uint16_t port, router_fn router){
 
    http_server_s *server = pvPortMalloc(sizeof(http_server_s));
 
    server->router = router;
    server->port = port;
 
    _http_prepare_pcb(server);
 
    return server;
 
}