Embedded websocket example

/* * Copyright (c) 2013-2015 the CivetWeb developers * Copyright (c) 2013 No Face Press, LLC * License http://opensource.org/licenses/mit-license.php MIT License */ // Simple example program on how to use Embedded C interface. #ifdef _WIN32 #include #else #include #endif #include #include "civetweb.h" #define DOCUMENT_ROOT "." #define PORT "8888" #define EXAMPLE_URI "/example" #define EXIT_URI "/exit" int exitNow = 0; int ExampleHandler(struct mg_connection *conn, void *cbdata) { mg_printf(conn, "HTTP/1.1 200 OK\r\nContent-Type: text/html\r\n\r\n"); mg_printf(conn, ""); mg_printf(conn, "

This is an example text from a C handler

"); mg_printf(conn, "

To see a page from the A handler click here

"); mg_printf(conn, "

To see a page from the A/B handler click here

"); mg_printf(conn, "

To see a page from the *.foo handler click here

"); mg_printf(conn, "

To test websocket handler click here

"); mg_printf(conn, "

To exit click here

", EXIT_URI); mg_printf(conn, "\n"); return 1; } int ExitHandler(struct mg_connection *conn, void *cbdata) { mg_printf(conn, "HTTP/1.1 200 OK\r\nContent-Type: text/plain\r\n\r\n"); mg_printf(conn, "Bye!\n"); exitNow = 1; return 1; } int AHandler(struct mg_connection *conn, void *cbdata) { mg_printf(conn, "HTTP/1.1 200 OK\r\nContent-Type: text/html\r\n\r\n"); mg_printf(conn, ""); mg_printf(conn, "

This is the A handler!!!

"); mg_printf(conn, "\n"); return 1; } int ABHandler(struct mg_connection *conn, void *cbdata) { mg_printf(conn, "HTTP/1.1 200 OK\r\nContent-Type: text/html\r\n\r\n"); mg_printf(conn, ""); mg_printf(conn, "

This is the AB handler!!!

"); mg_printf(conn, "\n"); return 1; } int FooHandler(struct mg_connection *conn, void *cbdata) { /* Handler may access the request info using mg_get_request_info */ struct mg_request_info * req_info = mg_get_request_info(conn); mg_printf(conn, "HTTP/1.1 200 OK\r\nContent-Type: text/html\r\n\r\n"); mg_printf(conn, ""); mg_printf(conn, "

This is the Foo handler!!!

"); mg_printf(conn, "

The request was:

%s %s HTTP/%s

", req_info->request_method, req_info->uri, req_info->http_version); mg_printf(conn, "\n"); return 1; } int WebSocketStartHandler(struct mg_connection *conn, void *cbdata) { mg_printf(conn, "HTTP/1.1 200 OK\r\nContent-Type: text/html\r\n\r\n"); mg_printf(conn, "\n"); mg_printf(conn, "\n\n"); mg_printf(conn, "\n"); mg_printf(conn, "Embedded websocket example\n"); #ifdef USE_WEBSOCKET /* mg_printf(conn, "\n"); ... xhtml style */ mg_printf(conn, "\n"); mg_printf(conn, "\n\n"); mg_printf(conn, "

No websocket connection yet

\n"); #else mg_printf(conn, "\n\n"); mg_printf(conn, "Example not compiled with USE_WEBSOCKET\n"); #endif mg_printf(conn, "\n\n"); return 1; } #ifdef USE_WEBSOCKET static struct mg_connection * ws_client; static unsigned long cnt; int WebSocketConnectHandler(const struct mg_connection * conn, void *cbdata) { int reject = 0; fprintf(stdout, "Websocket client %s\r\n\r\n", reject ? "rejected" : "accepted"); return reject; } void WebSocketReadyHandler(const struct mg_connection * conn, void *cbdata) { struct mg_context *ctx = mg_get_context((struct mg_connection *) /* TODO: check const_casts */ conn); const char * text = "Hello from the websocket ready handler"; /* TODO: check "const struct mg_connection *" vs "struct mg_connection *" everywhere */ mg_websocket_write((struct mg_connection *)conn, WEBSOCKET_OPCODE_TEXT, text, strlen(text)); fprintf(stdout, "Client added to the set of webserver connections\r\n\r\n"); mg_lock_context(ctx); ws_client = conn; mg_unlock_context(ctx); } int WebsocketDataHandler(const struct mg_connection * conn, int bits, char * data, size_t len, void *cbdata) { fprintf(stdout, "Websocket got data:\r\n"); fwrite(data, len, 1, stdout); fprintf(stdout, "\r\n\r\n"); return 1; } void WebSocketCloseHandler(const struct mg_connection * conn, void *cbdata) { struct mg_context *ctx = mg_get_context((struct mg_connection *) /* TODO: check const_casts */ conn); mg_lock_context(ctx); ws_client = NULL; mg_unlock_context(ctx); fprintf(stdout, "Client droped from the set of webserver connections\r\n\r\n"); } void InformWebsockets(struct mg_context *ctx) { char text[32]; mg_lock_context(ctx); if (ws_client) { sprintf(text, "%lu", ++cnt); mg_websocket_write(ws_client, WEBSOCKET_OPCODE_TEXT, text, strlen(text)); } mg_unlock_context(ctx); } #endif int main(int argc, char *argv[]) { const char * options[] = { "document_root", DOCUMENT_ROOT, "listening_ports", PORT, 0 }; struct mg_callbacks callbacks; struct mg_context *ctx; memset(&callbacks, 0, sizeof(callbacks)); ctx = mg_start(&callbacks, 0, options); mg_set_request_handler(ctx, EXAMPLE_URI, ExampleHandler, 0); mg_set_request_handler(ctx, EXIT_URI, ExitHandler, 0); mg_set_request_handler(ctx, "/a", AHandler, 0); mg_set_request_handler(ctx, "/a/b", ABHandler, 0); mg_set_request_handler(ctx, "**.foo$", FooHandler, 0); mg_set_request_handler(ctx, "/websocket", WebSocketStartHandler, 0); mg_set_websocket_handler(ctx, "/websocket", WebSocketConnectHandler, WebSocketReadyHandler, WebsocketDataHandler, WebSocketCloseHandler, 0); printf("Browse files at http://localhost:%s/\n", PORT); printf("Run example at http://localhost:%s%s\n", PORT, EXAMPLE_URI); printf("Exit at http://localhost:%s%s\n", PORT, EXIT_URI); while (!exitNow) { #ifdef _WIN32 Sleep(1000); #else sleep(1); #endif #ifdef USE_WEBSOCKET InformWebsockets(ctx); #endif } mg_stop(ctx); printf("Bye!\n"); return 0; }