1 files changed, 90 insertions, 0 deletions
diff --git a/src/basic/stat-util.h b/src/basic/stat-util.h
new file mode 100644
index 0000000..74fb725
--- /dev/null
+++ b/src/basic/stat-util.h
@@ -0,0 +1,90 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+#pragma once
+
+#include <stdbool.h>
+#include <stddef.h>
+#include <sys/stat.h>
+#include <sys/statfs.h>
+#include <sys/types.h>
+#include <sys/vfs.h>
+
+#include "macro.h"
+
+int is_symlink(const char *path);
+int is_dir(const char *path, bool follow);
+int is_dir_fd(int fd);
+int is_device_node(const char *path);
+
+int dir_is_empty_at(int dir_fd, const char *path);
+static inline int dir_is_empty(const char *path) {
+        return dir_is_empty_at(AT_FDCWD, path);
+}
+
+static inline int dir_is_populated(const char *path) {
+        int r;
+        r = dir_is_empty(path);
+        if (r < 0)
+                return r;
+        return !r;
+}
+
+bool null_or_empty(struct stat *st) _pure_;
+int null_or_empty_path(const char *fn);
+int null_or_empty_fd(int fd);
+
+int path_is_read_only_fs(const char *path);
+
+int files_same(const char *filea, const char *fileb, int flags);
+
+/* The .f_type field of struct statfs is really weird defined on
+ * different archs. Let's give its type a name. */
+typedef typeof(((struct statfs*)NULL)->f_type) statfs_f_type_t;
+
+bool is_fs_type(const struct statfs *s, statfs_f_type_t magic_value) _pure_;
+int fd_is_fs_type(int fd, statfs_f_type_t magic_value);
+int path_is_fs_type(const char *path, statfs_f_type_t magic_value);
+
+bool is_temporary_fs(const struct statfs *s) _pure_;
+bool is_network_fs(const struct statfs *s) _pure_;
+
+int fd_is_temporary_fs(int fd);
+int fd_is_network_fs(int fd);
+
+int fd_is_network_ns(int fd);
+
+int path_is_temporary_fs(const char *path);
+
+/* Because statfs.t_type can be int on some architectures, we have to cast
+ * the const magic to the type, otherwise the compiler warns about
+ * signed/unsigned comparison, because the magic can be 32 bit unsigned.
+ */
+#define F_TYPE_EQUAL(a, b) (a == (typeof(a)) b)
+
+int stat_verify_regular(const struct stat *st);
+int fd_verify_regular(int fd);
+
+int stat_verify_directory(const struct stat *st);
+int fd_verify_directory(int fd);
+
+/* glibc and the Linux kernel have different ideas about the major/minor size. These calls will check whether the
+ * specified major is valid by the Linux kernel's standards, not by glibc's. Linux has 20bits of minor, and 12 bits of
+ * major space. See MINORBITS in linux/kdev_t.h in the kernel sources. (If you wonder why we define _y here, instead of
+ * comparing directly >= 0: it's to trick out -Wtype-limits, which would otherwise complain if the type is unsigned, as
+ * such a test would be pointless in such a case.) */
+
+#define DEVICE_MAJOR_VALID(x)                                           \
+        ({                                                              \
+                typeof(x) _x = (x), _y = 0;                             \
+                _x >= _y && _x < (UINT32_C(1) << 12);                   \
+                                                                        \
+        })
+
+#define DEVICE_MINOR_VALID(x)                                           \
+        ({                                                              \
+                typeof(x) _x = (x), _y = 0;                             \
+                _x >= _y && _x < (UINT32_C(1) << 20);                   \
+        })
+
+int device_path_make_major_minor(mode_t mode, dev_t devno, char **ret);
+int device_path_make_canonical(mode_t mode, dev_t devno, char **ret);
+int device_path_parse_major_minor(const char *path, mode_t *ret_mode, dev_t *ret_devno);