Much closer to complete cleanup before exit.

adsbus/common.c

@@ -1,26 +1,52 @@
+#define _GNU_SOURCE
+
 #include <stdio.h>
 #include <stdbool.h>
 #include <assert.h>
 #include <stdlib.h>
 #include <string.h>
+#include <fcntl.h>
 #include <unistd.h>
 #include <signal.h>
+#include <errno.h>
 #include <uuid/uuid.h>
 
 #include "common.h"
 
 
-static int epoll_fd;
+static char server_id[UUID_LEN];
+static int peer_epoll_fd;
+static int peer_cancel_fd;
 static bool peer_canceled = false;
 
 static void peer_cancel(int signal) {
+	assert(!close(peer_cancel_fd));
+}
+
+static void peer_cancel_handler(struct peer *peer) {
+	fprintf(stderr, "X %s: Shutting down\n", server_id);
+	assert(!close(peer->fd));
+	free(peer);
 	peer_canceled = true;
 }
 
 void peer_init() {
+	uuid_gen(server_id);
+
+	peer_epoll_fd = epoll_create1(0);
+	assert(peer_epoll_fd >= 0);
+
+	int cancel_fds[2];
+	assert(!pipe2(cancel_fds, O_NONBLOCK));
+
+	struct peer *cancel_peer = malloc(sizeof(*cancel_peer));
+	assert(cancel_peer);
+	cancel_peer->fd = cancel_fds[0];
+	cancel_peer->event_handler = peer_cancel_handler;
+	peer_epoll_add(cancel_peer, EPOLLRDHUP);
+
+	peer_cancel_fd = cancel_fds[1];
 	signal(SIGINT, peer_cancel);
-	epoll_fd = epoll_create1(0);
-	assert(epoll_fd >= 0);
 }
 
 void peer_epoll_add(struct peer *peer, uint32_t events) {
@@ -30,28 +56,30 @@ void peer_epoll_add(struct peer *peer, uint32_t events) {
 			.ptr = peer,
 		},
 	};
-	assert(!epoll_ctl(epoll_fd, EPOLL_CTL_ADD, peer->fd, &ev));
+	assert(!epoll_ctl(peer_epoll_fd, EPOLL_CTL_ADD, peer->fd, &ev));
 }
 
 void peer_epoll_del(struct peer *peer) {
-	assert(!epoll_ctl(epoll_fd, EPOLL_CTL_DEL, peer->fd, NULL));
+	assert(!epoll_ctl(peer_epoll_fd, EPOLL_CTL_DEL, peer->fd, NULL));
 }
 
 void peer_loop() {
+	fprintf(stderr, "X %s: Starting event loop\n", server_id);
 	while (!peer_canceled) {
 #define MAX_EVENTS 10
 		struct epoll_event events[MAX_EVENTS];
-		int nfds = epoll_wait(epoll_fd, events, MAX_EVENTS, -1);
-		if (nfds < 0) {
-			perror("epoll_wait");
-			break;
+		int nfds = epoll_wait(peer_epoll_fd, events, MAX_EVENTS, -1);
+		if (nfds == -1 && errno == EINTR) {
+			continue;
 		}
+		assert(nfds > 0);
 
     for (int n = 0; n < nfds; n++) {
 			struct peer *peer = events[n].data.ptr;
 			peer->event_handler(peer);
 		}
 	}
+	assert(!close(peer_epoll_fd));
 }