feat: add an api to judge whether the conn was closed

Signed-off-by: Jianhui Zhao <zhaojh329@gmail.com>

src/connection.c

@@ -703,6 +703,13 @@ static struct http_parser_settings settings = {
     .on_message_complete = on_message_complete_cb
 };
 
+static bool conn_closed(struct uh_connection *conn)
+{
+    struct uh_connection_internal *conni = (struct uh_connection_internal *)conn;
+
+    return __sync_fetch_and_or(&conni->closed, 0);
+}
+
 static void conn_incref(struct uh_connection *conn)
 {
     struct uh_connection_internal *conni = (struct uh_connection_internal *)conn;
@@ -736,6 +743,11 @@ void conn_free(struct uh_connection_internal *conn)
 
     conn->flags |= CONN_F_CLOSED;
 
+    if (__sync_fetch_and_or(&conn->closed, 1)) {
+        conn_decref((struct uh_connection *)conn);
+        return;
+    }
+
     ev_timer_stop(loop, &conn->timer);
     ev_io_stop(loop, &conn->ior);
     ev_io_stop(loop, &conn->iow);
@@ -1061,6 +1073,7 @@ static void conn_init_cb(struct uh_connection *conn)
     conn->download_file = download_file;
     conn->serve_cgi = serve_cgi;
 
+    conn->closed = conn_closed;
     conn->close = conn_close;
 
     conn->incref = conn_incref;

src/connection.h

@@ -81,6 +81,7 @@ struct uh_connection_internal {
         int fd;
         uint64_t size;
     } file;
+    uint8_t closed;
     size_t refcount;
     struct ev_io ior;
     struct ev_io iow;

src/uhttpd.h

@@ -139,6 +139,7 @@ struct uh_connection {
     /* handle cgi */
     void (*serve_cgi)(struct uh_connection *conn, int event);
 
+    bool (*closed)(struct uh_connection *conn);
     void (*close)(struct uh_connection *conn);  /* close low level TCP connection */
     void (*incref)(struct uh_connection *conn);
     void (*decref)(struct uh_connection *conn);