dns: Use connection.c

This enables processing multiple requests at a time.

src/dns/dns-client.c

@@ -1,38 +1,34 @@
 /* Copyright (c) 2010-2018 Dovecot authors, see the included COPYING file */
 
 #include "lib.h"
-#include "ioloop.h"
 #include "istream.h"
 #include "ostream.h"
+#include "array.h"
+#include "strfuncs.h"
+#include "connection.h"
 #include "restrict-access.h"
 #include "master-service.h"
 
 #include <unistd.h>
 
-struct dns_client {
-	int fd;
-	struct istream *input;
-	struct ostream *output;
-	struct io *io;
-};
-
-#define MAX_INBUF_SIZE 1024
-#define MAX_OUTBUF_SIZE (1024*64)
-#define INPUT_TIMEOUT_MSECS (1000*10)
-
-static struct dns_client *dns_client = NULL;
-
-static void dns_client_destroy(struct dns_client **client);
+static struct connection_list *dns_clients = NULL;
 
-static int dns_client_input_line(struct dns_client *client, const char *line)
+static int dns_client_input_args(struct connection *client, const char *const *args)
 {
 	struct ip_addr *ips, ip;
 	const char *name;
 	unsigned int i, ips_count;
 	int ret;
 
-	if (str_begins(line, "IP\t")) {
-		ret = net_gethostbyname(line + 3, &ips, &ips_count);
+	if (strcmp(args[0], "QUIT") == 0) {
+		return -1;
+	} else if (args[1] == NULL) {
+		i_error("Got empty request");
+		return -1;
+	}
+
+	if (strcmp(args[0], "IP") == 0) {
+		ret = net_gethostbyname(args[1], &ips, &ips_count);
 		if (ret == 0 && ips_count == 0) {
 			/* shouldn't happen, but fix it anyway.. */
 			ret = EAI_NONAME;
@@ -44,12 +40,13 @@ static int dns_client_input_line(struct dns_client *client, const char *line)
 			o_stream_nsend_str(client->output,
 				t_strdup_printf("0 %u\n", ips_count));
 			for (i = 0; i < ips_count; i++) {
+				const char *ip = net_ip2addr(&ips[i]);
 				o_stream_nsend_str(client->output, t_strconcat(
 					net_ip2addr(&ips[i]), "\n", NULL));
 			}
 		}
-	} else if (str_begins(line, "NAME\t")) {
-		if (net_addr2ip(line+5, &ip) < 0)
+	} else if (strcmp(args[0], "NAME") == 0) {
+		if (net_addr2ip(args[1], &ip) < 0)
 			o_stream_nsend_str(client->output, "-1\n");
 		else if ((ret = net_gethostbyaddr(&ip, &name)) != 0) {
 			o_stream_nsend_str(client->output,
@@ -58,74 +55,37 @@ static int dns_client_input_line(struct dns_client *client, const char *line)
 			o_stream_nsend_str(client->output,
 				t_strdup_printf("0 %s\n", name));
 		}
-	} else if (strcmp(line, "QUIT") == 0) {
-		return -1;
 	} else {
 		o_stream_nsend_str(client->output, "Unknown command\n");
 	}
 
-	if (client->output->overflow)
-		return -1;
-	return 0;
-}
-
-static void dns_client_input(struct dns_client *client)
-{
-	const char *line;
-	int ret = 0;
-
-	o_stream_cork(client->output);
-	while ((line = i_stream_read_next_line(client->input)) != NULL) {
-		if (dns_client_input_line(client, line) < 0) {
-			ret = -1;
-			break;
-		}
-	}
-	o_stream_uncork(client->output);
-
-	if (client->input->eof || client->input->stream_errno != 0 || ret < 0)
-		dns_client_destroy(&client);
-}
-
-static struct dns_client *dns_client_create(int fd)
-{
-	struct dns_client *client;
-
-	client = i_new(struct dns_client, 1);
-	client->fd = fd;
-	client->input = i_stream_create_fd(fd, MAX_INBUF_SIZE);
-	client->output = o_stream_create_fd(fd, MAX_OUTBUF_SIZE);
-	o_stream_set_no_error_handling(client->output, TRUE);
-	client->io = io_add(fd, IO_READ, dns_client_input, client);
-	return client;
+	return 1;
 }
 
-static void dns_client_destroy(struct dns_client **_client)
+static void dns_client_destroy(struct connection *client)
 {
-	struct dns_client *client = *_client;
-
-	*_client = NULL;
-
-	io_remove(&client->io);
-	i_stream_destroy(&client->input);
-	o_stream_destroy(&client->output);
-	if (close(client->fd) < 0)
-		i_error("close() failed: %m");
+	connection_deinit(client);
 	i_free(client);
-
-	dns_client = NULL;
 	master_service_client_connection_destroyed(master_service);
 }
 
-static void client_connected(struct master_service_connection *conn)
-{
-	if (dns_client != NULL) {
-		i_error("dns-client must be configured with client_limit=1");
-		return;
-	}
+static const struct connection_vfuncs dns_client_vfuncs = {
+	.input_args = dns_client_input_args,
+	.destroy = dns_client_destroy
+};
+
+static const struct connection_settings dns_client_set = {
+	.dont_send_version = TRUE,
+	.input_max_size = (size_t)-1,
+	.output_max_size = (size_t)-1
+};
 
-	master_service_client_connection_accept(conn);
-	dns_client = dns_client_create(conn->fd);
+static void client_connected(struct master_service_connection *master_conn)
+{
+	struct connection *conn = i_new(struct connection, 1);
+	master_service_client_connection_accept(master_conn);
+	connection_init_server(dns_clients, conn, master_conn->name,
+			       master_conn->fd, master_conn->fd);
 }
 
 int main(int argc, char *argv[])
@@ -140,9 +100,13 @@ int main(int argc, char *argv[])
 
 	master_service_init_finish(master_service);
 
+	/* setup connection list */
+	dns_clients = connection_list_init(&dns_client_set, &dns_client_vfuncs);
+
 	master_service_run(master_service, client_connected);
-	if (dns_client != NULL)
-		dns_client_destroy(&dns_client);
+
+	/* disconnect all clients */
+	connection_list_deinit(&dns_clients);
 
 	master_service_deinit(&master_service);
         return 0;