Finally find a clean ownership solution for resolve().

adsbus/resolve.c

@@ -2,6 +2,7 @@
 #include <fcntl.h>
 #include <netdb.h>
 #include <stdlib.h>
+#include <string.h>
 #include <unistd.h>
 #include <pthread.h>
 
@@ -9,53 +10,39 @@
 
 #include "resolve.h"
 
-struct resolve_request {
+struct resolve {
 	int fd;
-	const char *node;
-	const char *service;
-	int flags;
-	struct addrinfo **addrs;
-	const char **error;
-};
 
-struct resolve_peer {
-	struct peer peer;
-	struct peer *inner_peer;
+	char *node;
+	char *service;
+	int flags;
+
+	int err;
+	struct addrinfo *addrs;
 };
 
 static pthread_t resolve_thread;
 static int resolve_write_fd;
 
-static void resolve_handler(struct peer *peer) {
-	struct resolve_peer *resolve_peer = (struct resolve_peer *) peer;
-
-	assert(!close(resolve_peer->peer.fd));
-
-	peer_call(resolve_peer->inner_peer);
-	free(resolve_peer);
-}
-
 static void *resolve_main(void *arg) {
 	int fd = (int) (intptr_t) arg;
-	struct resolve_request *request;
-	ssize_t ret;
-	while ((ret = read(fd, &request, sizeof(request))) == sizeof(request)) {
+	struct resolve *res;
+	ssize_t len;
+	while ((len = read(fd, &res, sizeof(res))) == sizeof(res)) {
 		struct addrinfo hints = {
 			.ai_family = AF_UNSPEC,
 			.ai_socktype = SOCK_STREAM,
-			.ai_flags = AI_V4MAPPED | AI_ADDRCONFIG | request->flags,
+			.ai_flags = AI_V4MAPPED | AI_ADDRCONFIG | res->flags,
 		};
-		int err = getaddrinfo(request->node, request->service, &hints, request->addrs);
-		if (err) {
-			*request->addrs = NULL;
-			*request->error = gai_strerror(err);
-		} else {
-			*request->error = NULL;
-		}
-		close(request->fd);
-		free(request);
+		res->err = getaddrinfo(res->node, res->service, &hints, &res->addrs);
+		free(res->node);
+		free(res->service);
+		res->node = res->service = NULL;
+		assert(write(res->fd, &res, sizeof(res)) == sizeof(res));
+		close(res->fd);
+		res->fd = -1;
 	}
-	assert(!ret);
+	assert(!len);
 	assert(!close(fd));
 	return NULL;
 }
@@ -72,22 +59,28 @@ void resolve_cleanup() {
 	assert(!pthread_join(resolve_thread, NULL));
 }
 
-void resolve(struct peer *peer, const char *node, const char *service, int flags, struct addrinfo **addrs, const char **error) {
+void resolve(struct peer *peer, const char *node, const char *service, int flags) {
 	int fds[2];
 	assert(!pipe2(fds, O_CLOEXEC));
 
-	struct resolve_request *request = malloc(sizeof(*request));
-	request->fd = fds[1];
-	request->node = node;
-	request->service = service;
-	request->flags = flags;
-	request->addrs = addrs;
-	request->error = error;
-	assert(write(resolve_write_fd, &request, sizeof(request)) == sizeof(request));
+	struct resolve *res = malloc(sizeof(*res));
+	res->fd = fds[1];
+	res->node = strdup(node);
+	res->service = strdup(service);
+	res->flags = flags;
+	assert(write(resolve_write_fd, &res, sizeof(res)) == sizeof(res));
 
-	struct resolve_peer *resolve_peer = malloc(sizeof(*resolve_peer));
-	resolve_peer->peer.fd = fds[0];
-	resolve_peer->peer.event_handler = resolve_handler;
-	resolve_peer->inner_peer = peer;
-	peer_epoll_add((struct peer *) resolve_peer, EPOLLRDHUP);
+	peer->fd = fds[0];
+	peer_epoll_add(peer, EPOLLIN);
+}
+
+int resolve_result(struct peer *peer, struct addrinfo **addrs) {
+	struct resolve *res;
+	assert(read(peer->fd, &res, sizeof(res)) == sizeof(res));
+	assert(!close(peer->fd));
+	peer->fd = -1;
+	*addrs = res->addrs;
+	int err = res->err;
+	free(res);
+	return err;
 }