Add custom server API and runtime limits

site/doc/areas/sys.txt

@@ -22,3 +22,5 @@ zip_read
 zip_extract
 gz_compress
 gz_uncompress
+server_start_http
+server_stop

site/doc/pages/server_start_http.txt

@@ -0,0 +1,38 @@
+:sig
+pid_t server_start_http(String key, String socket_fn_or_port, String call_uce_filename, String call_function = "")
+
+:params
+key : runtime-wide server key
+socket_fn_or_port : TCP port number or Unix socket path to listen on
+call_uce_filename : `.uce` file containing `SERVE_HTTP` handlers
+call_function : optional named `SERVE_HTTP:name` handler
+return value : listener process PID, or `0` when it could not be started
+
+:see
+>sys
+server_stop
+task
+
+:content
+Starts or updates a custom HTTP listener backed by a UCE handler file.
+
+The server key is runtime-wide. Calling `server_start_http()` again with the same key and the same bind target updates the mapped UCE file/function without restarting the listener. If the bind target changes, UCE stops the old listener and starts a replacement.
+
+`socket_fn_or_port` may be a numeric TCP port such as `"19091"` or a Unix socket path.
+
+Handler files use `SERVE_HTTP`:
+
+```uce
+SERVE_HTTP(Request* req)
+{
+    req->header["Content-Type"] = "text/plain; charset=utf-8";
+    print("hello from custom HTTP\n");
+}
+
+SERVE_HTTP:admin(Request* req)
+{
+    print("named handler\n");
+}
+```
+
+The custom server dispatcher uses the same nonblocking HTTP listener machinery as the built-in HTTP/WebSocket path, and hands request/response data through the normal `Request` object. Handler code may block in the first implementation; future worker dispatch can be added without changing this API.

site/doc/pages/server_stop.txt

@@ -0,0 +1,19 @@
+:sig
+bool server_stop(String key)
+
+:params
+key : runtime-wide server key used with `server_start_http()`
+return value : `true` when no listener remains or a stop signal was sent
+
+:see
+>sys
+server_start_http
+
+:content
+Stops a custom server listener by key and removes its registry config.
+
+```uce
+server_stop("site-tests-http");
+```
+
+`server_stop()` currently targets custom servers started through `server_start_http()`. The same key model is intended to extend to future `server_start_tcp()` and `server_start_udp()` helpers.

site/tests/servers/http.uce

@@ -0,0 +1,16 @@
+SERVE_HTTP(Request* req)
+{
+	req->header["Content-Type"] = "text/plain; charset=utf-8";
+	print("custom-http-default\n");
+	print("method=", req->params["REQUEST_METHOD"], "\n");
+	print("uri=", req->params["REQUEST_URI"], "\n");
+	print("body=", req->in, "\n");
+}
+
+SERVE_HTTP:named(Request* req)
+{
+	req->header["Content-Type"] = "text/plain; charset=utf-8";
+	print("custom-http-named\n");
+	print("function=", req->params["UCE_SERVE_HTTP_FUNCTION"], "\n");
+	print("query=", req->params["QUERY_STRING"], "\n");
+}

site/tests/services.uce

@@ -25,7 +25,7 @@ RENDER(Request& context)
 			failed++;
 	};
 
-	u64 sockfd = socket_connect("localhost", 80);
+	u64 sockfd = socket_connect("127.0.0.1", 80);
 	if(sockfd != 0)
 	{
 		bool write_ok = socket_write(sockfd, "GET /tests/index.uce HTTP/1.0\r\nHost: uce.openfu.com\r\n\r\n");
@@ -39,7 +39,28 @@ RENDER(Request& context)
 	}
 	else
 	{
-		mark("socket_connect() / socket_write() / socket_read()", "fail", "socket_connect(localhost, 80) returned 0");
+		mark("socket_connect() / socket_write() / socket_read()", "fail", "socket_connect(127.0.0.1, 80) returned 0");
+	}
+
+	pid_t custom_http_pid = server_start_http("site-tests-http", "19091", "servers/http.uce", "named");
+	usleep(200000);
+	u64 custom_http_sockfd = socket_connect("127.0.0.1", 19091);
+	if(custom_http_sockfd != 0)
+	{
+		bool write_ok = socket_write(custom_http_sockfd, "GET /custom-test?alpha=1 HTTP/1.0\r\nHost: localhost\r\n\r\n");
+		String response = socket_read(custom_http_sockfd, 4096, 2);
+		socket_close(custom_http_sockfd);
+		server_stop("site-tests-http");
+		mark(
+			"server_start_http() / SERVE_HTTP:named",
+			(custom_http_pid != 0 && write_ok && response.find("custom-http-named") != String::npos && response.find("query=alpha=1") != String::npos) ? "pass" : "fail",
+			response.substr(0, response.length() > 260 ? 260 : response.length())
+		);
+	}
+	else
+	{
+		server_stop("site-tests-http");
+		mark("server_start_http() / SERVE_HTTP:named", "fail", "socket_connect(127.0.0.1, 19091) returned 0; pid=" + std::to_string(custom_http_pid));
 	}
 
 	u64 memfd = memcache_connect();
@@ -60,7 +81,7 @@ RENDER(Request& context)
 	}
 
 	MySQL mysql;
-	mysql.connect("localhost", "root", "");
+	mysql.connect("127.0.0.1", "root", "");
 	String mysql_error_text = trim(mysql.error());
 	if(mysql_error_text != "")
 	{