tree-wide: use -EBADF for fd initialization

-1 was used everywhere, but -EBADF or -EBADFD started being used in various
places. Let's make things consistent in the new style.

Note that there are two candidates:
EBADF 9 Bad file descriptor
EBADFD 77 File descriptor in bad state

Since we're initializating the fd, we're just assigning a value that means
"no fd yet", so it's just a bad file descriptor, and the first errno fits
better. If instead we had a valid file descriptor that became invalid because
of some operation or state change, the other errno would fit better.

In some places, initialization is dropped if unnecessary.

src/nspawn/nspawn-cgroup.c

@@ -20,7 +20,7 @@
 #include "user-util.h"
 
 static int chown_cgroup_path(const char *path, uid_t uid_shift) {
-        _cleanup_close_ int fd = -1;
+        _cleanup_close_ int fd = -EBADF;
 
         fd = open(path, O_RDONLY|O_CLOEXEC|O_DIRECTORY);
         if (fd < 0)

src/nspawn/nspawn-expose-ports.c

@@ -160,7 +160,7 @@ int expose_port_execute(sd_netlink *rtnl, FirewallContext **fw_ctx, ExposePort *
 }
 
 int expose_port_send_rtnl(int send_fd) {
-        _cleanup_close_ int fd = -1;
+        _cleanup_close_ int fd = -EBADF;
         int r;
 
         assert(send_fd >= 0);

src/nspawn/nspawn-patch-uid.c

@@ -28,7 +28,7 @@ static int get_acl(int fd, const char *name, acl_type_t type, acl_t *ret) {
         assert(ret);
 
         if (name) {
-                _cleanup_close_ int child_fd = -1;
+                _cleanup_close_ int child_fd = -EBADF;
 
                 child_fd = openat(fd, name, O_PATH|O_CLOEXEC|O_NOFOLLOW);
                 if (child_fd < 0)
@@ -53,7 +53,7 @@ static int set_acl(int fd, const char *name, acl_type_t type, acl_t acl) {
         assert(acl);
 
         if (name) {
-                _cleanup_close_ int child_fd = -1;
+                _cleanup_close_ int child_fd = -EBADF;
 
                 child_fd = openat(fd, name, O_PATH|O_CLOEXEC|O_NOFOLLOW);
                 if (child_fd < 0)

src/nspawn/nspawn-setuid.c

@@ -93,7 +93,7 @@ int change_uid_gid(const char *user, bool chown_stdio, char **ret_home) {
         _cleanup_free_ gid_t *gids = NULL;
         _cleanup_free_ char *home = NULL, *line = NULL;
         _cleanup_fclose_ FILE *f = NULL;
-        _cleanup_close_ int fd = -1;
+        _cleanup_close_ int fd = -EBADF;
         unsigned n_gids = 0;
         uid_t uid;
         gid_t gid;

src/nspawn/nspawn.c

@@ -2459,7 +2459,7 @@ static int setup_credentials(const char *root) {
 
         for (size_t i = 0; i < arg_n_credentials; i++) {
                 _cleanup_free_ char *j = NULL;
-                _cleanup_close_ int fd = -1;
+                _cleanup_close_ int fd = -EBADF;
 
                 j = path_join(q, arg_credentials[i].id);
                 if (!j)
@@ -2500,7 +2500,7 @@ static int setup_credentials(const char *root) {
 static int setup_kmsg(int fd_inner_socket) {
         _cleanup_(unlink_and_freep) char *from = NULL;
         _cleanup_free_ char *fifo = NULL;
-        _cleanup_close_ int fd = -1;
+        _cleanup_close_ int fd = -EBADF;
         int r;
 
         assert(fd_inner_socket >= 0);
@@ -3590,7 +3590,7 @@ static int inner_child(
 }
 
 static int setup_notify_child(void) {
-        _cleanup_close_ int fd = -1;
+        _cleanup_close_ int fd = -EBADF;
         static const union sockaddr_union sa = {
                 .un.sun_family = AF_UNIX,
                 .un.sun_path = NSPAWN_NOTIFY_SOCKET_PATH,
@@ -3631,7 +3631,7 @@ static int outer_child(
 
         _cleanup_(bind_user_context_freep) BindUserContext *bind_user_context = NULL;
         _cleanup_strv_free_ char **os_release_pairs = NULL;
-        _cleanup_close_ int fd = -1, mntns_fd = -EBADF;
+        _cleanup_close_ int fd = -EBADF, mntns_fd = -EBADF;
         bool idmap = false;
         const char *p;
         pid_t pid;
@@ -4760,7 +4760,7 @@ static int run_container(
         int ifi = 0, r;
         ssize_t l;
         sigset_t mask_chld;
-        _cleanup_close_ int child_netns_fd = -1;
+        _cleanup_close_ int child_netns_fd = -EBADF;
 
         assert_se(sigemptyset(&mask_chld) == 0);
         assert_se(sigaddset(&mask_chld, SIGCHLD) == 0);
@@ -5168,7 +5168,7 @@ static int run_container(
         }
 
         if (arg_console_mode != CONSOLE_PIPE) {
-                _cleanup_close_ int fd = -1;
+                _cleanup_close_ int fd = -EBADF;
                 PTYForwardFlags flags = 0;
 
                 /* Retrieve the master pty allocated by inner child */
@@ -5236,7 +5236,7 @@ static int run_container(
                         return r;
 
                 if (r == 0) {
-                        _cleanup_close_ int parent_netns_fd = -1;
+                        _cleanup_close_ int parent_netns_fd = -EBADF;
 
                         r = namespace_open(getpid(), NULL, NULL, &parent_netns_fd, NULL, NULL);
                         if (r < 0) {
@@ -5373,7 +5373,7 @@ static int initialize_rlimits(void) {
 }
 
 static int cant_be_in_netns(void) {
-        _cleanup_close_ int fd = -1;
+        _cleanup_close_ int fd = -EBADF;
         struct ucred ucred;
         int r;