tree-wide: use -EBADF more

src/basic/async.c

@@ -103,5 +103,5 @@ int asynchronous_close(int fd) {
                          assert_se(close_nointr(fd) != -EBADF);
         }
 
-        return -1;
+        return -EBADF;
 }

src/basic/chase-symlinks.c

@@ -206,7 +206,7 @@ int chase_symlinks_at(
 
         for (todo = buffer;;) {
                 _cleanup_free_ char *first = NULL;
-                _cleanup_close_ int child = -1;
+                _cleanup_close_ int child = -EBADF;
                 struct stat st;
                 const char *e;
 

src/basic/fd-util.c

@@ -246,7 +246,7 @@ static int close_all_fds_frugal(const int except[], size_t n_except) {
                                        "Refusing to loop over %d potential fds.",
                                        max_fd);
 
-        for (int fd = 3; fd >= 0; fd = fd < max_fd ? fd + 1 : -1) {
+        for (int fd = 3; fd >= 0; fd = fd < max_fd ? fd + 1 : -EBADF) {
                 int q;
 
                 if (fd_in_set(fd, except, n_except))

src/basic/fd-util.h

@@ -22,8 +22,8 @@ int safe_close(int fd);
 void safe_close_pair(int p[static 2]);
 
 static inline int safe_close_above_stdio(int fd) {
-        if (fd < 3) /* Don't close stdin/stdout/stderr, but still invalidate the fd by returning -1 */
-                return -1;
+        if (fd < 3) /* Don't close stdin/stdout/stderr, but still invalidate the fd by returning -EBADF. */
+                return -EBADF;
 
         return safe_close(fd);
 }
@@ -87,7 +87,7 @@ int fd_move_above_stdio(int fd);
 int rearrange_stdio(int original_input_fd, int original_output_fd, int original_error_fd);
 
 static inline int make_null_stdio(void) {
-        return rearrange_stdio(-1, -1, -1);
+        return rearrange_stdio(-EBADF, -EBADF, -EBADF);
 }
 
 /* Like TAKE_PTR() but for file descriptors, resetting them to -1 */

src/basic/fileio.c

@@ -767,7 +767,7 @@ int read_full_file_full(
 
         r = xfopenat(dir_fd, filename, "re", 0, &f);
         if (r < 0) {
-                _cleanup_close_ int sk = -1;
+                _cleanup_close_ int sk = -EBADF;
 
                 /* ENXIO is what Linux returns if we open a node that is an AF_UNIX socket */
                 if (r != -ENXIO)