libsagui-docs/example_httpsrv_sse_8c-example.html

/*                         _

 *   ___  __ _  __ _ _   _(_)

 *  / __|/ _` |/ _` | | | | |

 *  \__ \ (_| | (_| | |_| | |

 *  |___/\__,_|\__, |\__,_|_|

 *             |___/

 *

 * Cross-platform library which helps to develop web servers or frameworks.

 *

 * Copyright (C) 2016-2020 Silvio Clecio <silvioprog@gmail.com>

 *

 * Sagui library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * Sagui library is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with Sagui library; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */


#include <stdio.h>

#include <stdlib.h>

#include <stdint.h>

#include <string.h>

#ifdef _WIN32

#include <windows.h>

#else /* _WIN32 */

#include <unistd.h>

#endif /* _WIN32 */

#include <sagui.h>


/* NOTE: Error checking has been omitted to make it clear. */


#define PAGE                                                                   \

  "<html>\n"                                                                   \

  "<head>\n"                                                                   \

  "<title>SSE example</title>\n"                                               \

  "</head><body><h2 id=\"counter\">Please wait ...</h2>\n"                     \

  "<script>\n"                                                                 \

  "const es = new EventSource('/');\n"                                         \

  "es.onmessage = function (ev) {\n"                                           \

  "  document.getElementById('counter').innerText = 'Counting: ' + ev.data;\n" \

  "};\n"                                                                       \

  "</script>\n"                                                                \

  "</body>\n"                                                                  \

  "</html>"


static unsigned int COUNT = 0;


#ifdef _WIN32

#define sleep Sleep

#endif /* _WIN32 */


static ssize_t sse_read_cb(__SG_UNUSED void *handle, uint64_t offset, char *buf,

                           size_t size) {

  char msg[20];

  if (offset == 0) {

    size = sprintf(msg, "retry: 1000\n");

  } else {

    size = sprintf(msg, "data: %d\n\n", ++COUNT);

    sleep(1);

  }

  memcpy(buf, msg, size);

  msg[size] = '\0';

  return size;

}


static void req_cb(__SG_UNUSED void *cls, struct sg_httpreq *req,

                   struct sg_httpres *res) {

  struct sg_strmap *pair;

  struct sg_strmap **req_headers = sg_httpreq_headers(req);

  struct sg_strmap **res_headers = sg_httpres_headers(res);

  if (sg_strmap_find(*req_headers, "Accept", &pair) == 0 &&

      strstr(sg_strmap_val(pair), "text/event-stream")) {

    sg_strmap_set(res_headers, "Access-Control-Allow-Origin", "*");

    sg_strmap_set(res_headers, "Content-Type", "text/event-stream");

    sg_httpres_sendstream(res, 0, sse_read_cb, NULL, NULL, 200);

    return;

  }

  if (strcmp(sg_httpreq_path(req), "/favicon.ico") == 0) {

    sg_httpres_send(res, "", "", 204);

    return;

  }

  sg_httpres_send(res, PAGE, "text/html; charset=utf-8", 200);

}


int main(int argc, const char *argv[]) {

  struct sg_httpsrv *srv;

  if (argc != 2) {

    printf("%s <PORT>\n", argv[0]);

    return EXIT_FAILURE;

  }

  srv = sg_httpsrv_new(req_cb, NULL);

  if (!sg_httpsrv_listen(srv, strtol(argv[1], NULL, 10), true)) {

    sg_httpsrv_free(srv);

    return EXIT_FAILURE;

  }

  fprintf(stdout, "Server running at http://localhost:%d\n",

          sg_httpsrv_port(srv));

  fflush(stdout);

  getchar();

  sg_httpsrv_free(srv);

  return EXIT_SUCCESS;

}

sg_httpres_headers
struct sg_strmap ** sg_httpres_headers(struct sg_httpres *res)

sg_httpsrv_new
struct sg_httpsrv * sg_httpsrv_new(sg_httpreq_cb cb, void *cls) __attribute__((malloc))

sg_httpreq_headers
struct sg_strmap ** sg_httpreq_headers(struct sg_httpreq *req)

sg_httpsrv_free
void sg_httpsrv_free(struct sg_httpsrv *srv)

sg_httpreq_path
const char * sg_httpreq_path(struct sg_httpreq *req)

sg_httpres_sendstream
int sg_httpres_sendstream(struct sg_httpres *res, uint64_t size, sg_read_cb read_cb, void *handle, sg_free_cb free_cb, unsigned int status)

sg_httpres_send
#define sg_httpres_send(res, val, content_type, status)
Definition sagui.h:1032

sg_httpsrv_listen
bool sg_httpsrv_listen(struct sg_httpsrv *srv, uint16_t port, bool threaded)

sg_httpsrv_port
uint16_t sg_httpsrv_port(struct sg_httpsrv *srv)

sg_strmap_set
int sg_strmap_set(struct sg_strmap **map, const char *name, const char *val)

sg_strmap_val
const char * sg_strmap_val(struct sg_strmap *pair)

sg_strmap_find
int sg_strmap_find(struct sg_strmap *map, const char *name, struct sg_strmap **pair)

sagui.h

sg_httpreq

sg_httpres

sg_httpsrv

sg_strmap