optimize: persist fdlist for duration of main_loop

constant malloc and realloc was wasting lots of time

3 files changed, 9 insertions, 2 deletions

diff --git a/common/utils.c b/common/utils.c
index 6803941..f66d889 100644
--- a/common/utils.c
+++ b/common/utils.c
@@ -65,6 +65,11 @@ void fdlist_free(struct fdlist *list)
         list->fds = NULL;
 }
 
+void fdlist_reset(struct fdlist *list)
+{
+        list->count = 0;
+}
+
 void collection_init(struct collection *col)
 {
         col->list = malloc(sizeof(void *));
diff --git a/common/utils.h b/common/utils.h
index ad4ac9d..f9cfa93 100644
--- a/common/utils.h
+++ b/common/utils.h
@@ -39,6 +39,7 @@ struct fdlist {
 void fdlist_create(struct fdlist *list);
 void fdlist_add(struct fdlist *list, enum fdowner owner, int fd, short events);
 void fdlist_free(struct fdlist *list);
+void fdlist_reset(struct fdlist *list);
 
 struct collection {
         void **list;
diff --git a/daemon/main.c b/daemon/main.c
index 893f26d..f85d034 100644
--- a/daemon/main.c
+++ b/daemon/main.c
@@ -138,6 +138,7 @@ int main_loop(int listenfd)
         int to, cnt, i, dto;
         struct fdlist pollfds;
 
+        fdlist_create(&pollfds);
         while(!should_exit) {
                 usbmuxd_log(LL_FLOOD, "main_loop iteration");
                 to = usb_get_timeout();
@@ -147,7 +148,7 @@ int main_loop(int listenfd)
                 if(dto < to)
                         to = dto;
 
-                fdlist_create(&pollfds);
+                fdlist_reset(&pollfds);
                 fdlist_add(&pollfds, FD_LISTEN, listenfd, POLLIN);
                 usb_get_fds(&pollfds);
                 client_get_fds(&pollfds);
@@ -201,8 +202,8 @@ int main_loop(int listenfd)
                                 }
                         }
                 }
-                fdlist_free(&pollfds);
         }
+        fdlist_free(&pollfds);
         return 0;
 }