stat-util: Add xstatfsat()

src/basic/stat-util.c

@@ -455,6 +455,20 @@ int statx_fallback(int dfd, const char *path, int flags, unsigned mask, struct s
         return 0;
 }
 
+int xstatfsat(int dir_fd, const char *path, struct statfs *ret) {
+        _cleanup_close_ int fd = -EBADF;
+
+        assert(dir_fd >= 0 || dir_fd == AT_FDCWD);
+        assert(path);
+        assert(ret);
+
+        fd = xopenat(dir_fd, path, O_PATH|O_CLOEXEC|O_NOCTTY, 0);
+        if (fd < 0)
+                return fd;
+
+        return RET_NERRNO(fstatfs(fd, ret));
+}
+
 void inode_hash_func(const struct stat *q, struct siphash *state) {
         siphash24_compress(&q->st_dev, sizeof(q->st_dev), state);
         siphash24_compress(&q->st_ino, sizeof(q->st_ino), state);

src/basic/stat-util.h

@@ -79,6 +79,8 @@ bool statx_mount_same(const struct new_statx *a, const struct new_statx *b);
 
 int statx_fallback(int dfd, const char *path, int flags, unsigned mask, struct statx *sx);
 
+int xstatfsat(int dir_fd, const char *path, struct statfs *ret);
+
 #if HAS_FEATURE_MEMORY_SANITIZER
 #  warning "Explicitly initializing struct statx, to work around msan limitation. Please remove as soon as msan has been updated to not require this."
 #  define STRUCT_STATX_DEFINE(var)              \