From: Lennart Poettering <lennart@poettering.net>
Date: Fri, 22 Oct 2021 22:21:20 +0000 (+0200)
Subject: dirent-util: move getdents64() related definitions to common header
X-Git-Tag: v250-rc1~426^2~5
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=ca664db25860d7fcd581380e24ad74f510c1f40f;p=thirdparty%2Fsystemd.git

dirent-util: move getdents64() related definitions to common header

We want to reuse getdents64() wherever necessary, let's hence move
definitions useful for that into public code.
---

diff --git a/src/basic/dirent-util.h b/src/basic/dirent-util.h
index c7956e7c1b7..73e78102a59 100644
--- a/src/basic/dirent-util.h
+++ b/src/basic/dirent-util.h
@@ -33,3 +33,21 @@ struct dirent *readdir_no_dot(DIR *dirp);
                         }                                               \
                         break;                                          \
                 } else
+
+/* Maximum space one dirent structure might require at most */
+#define DIRENT_SIZE_MAX CONST_MAX(sizeof(struct dirent), offsetof(struct dirent, d_name) + NAME_MAX + 1)
+
+/* Only if 64bit off_t is enabled struct dirent + struct dirent64 are actually the same. We require this, and
+ * we want them to be interchangeable to make getdents64() work, hence verify that. */
+assert_cc(_FILE_OFFSET_BITS == 64);
+assert_cc(sizeof(struct dirent) == sizeof(struct dirent64));
+assert_cc(offsetof(struct dirent, d_ino) == offsetof(struct dirent64, d_ino));
+assert_cc(sizeof_field(struct dirent, d_ino) == sizeof_field(struct dirent64, d_ino));
+assert_cc(offsetof(struct dirent, d_off) == offsetof(struct dirent64, d_off));
+assert_cc(sizeof_field(struct dirent, d_off) == sizeof_field(struct dirent64, d_off));
+assert_cc(offsetof(struct dirent, d_reclen) == offsetof(struct dirent64, d_reclen));
+assert_cc(sizeof_field(struct dirent, d_reclen) == sizeof_field(struct dirent64, d_reclen));
+assert_cc(offsetof(struct dirent, d_type) == offsetof(struct dirent64, d_type));
+assert_cc(sizeof_field(struct dirent, d_type) == sizeof_field(struct dirent64, d_type));
+assert_cc(offsetof(struct dirent, d_name) == offsetof(struct dirent64, d_name));
+assert_cc(sizeof_field(struct dirent, d_name) == sizeof_field(struct dirent64, d_name));
diff --git a/src/basic/recurse-dir.c b/src/basic/recurse-dir.c
index 86018c8d29c..adc855955a6 100644
--- a/src/basic/recurse-dir.c
+++ b/src/basic/recurse-dir.c
@@ -25,9 +25,6 @@ static bool ignore_dirent(const struct dirent *de, RecurseDirFlags flags) {
                 dot_or_dot_dot(de->d_name);
 }
 
-/* Maximum space one direent structure might require at most */
-#define DIRENT_SIZE_MAX MAX(sizeof(struct dirent), offsetof(struct dirent, d_name) + NAME_MAX + 1)
-
 int readdir_all(int dir_fd,
                 RecurseDirFlags flags,
                 DirectoryEntries **ret) {
@@ -39,24 +36,9 @@ int readdir_all(int dir_fd,
         assert(dir_fd >= 0);
 
         /* Returns an array with pointers to "struct dirent" directory entries, optionally sorted. Free the
-         * array with readdir_all_freep(). */
-
-        /* Only if 64bit off_t is enabled struct dirent + struct dirent64 are actually the same. We require
-         * this, and we want them to be interchangeable, hence verify that. */
-        assert_cc(_FILE_OFFSET_BITS == 64);
-        assert_cc(sizeof(struct dirent) == sizeof(struct dirent64));
-        assert_cc(offsetof(struct dirent, d_ino) == offsetof(struct dirent64, d_ino));
-        assert_cc(sizeof(((struct dirent*) NULL)->d_ino) == sizeof(((struct dirent64*) NULL)->d_ino));
-        assert_cc(offsetof(struct dirent, d_off) == offsetof(struct dirent64, d_off));
-        assert_cc(sizeof(((struct dirent*) NULL)->d_off) == sizeof(((struct dirent64*) NULL)->d_off));
-        assert_cc(offsetof(struct dirent, d_reclen) == offsetof(struct dirent64, d_reclen));
-        assert_cc(sizeof(((struct dirent*) NULL)->d_reclen) == sizeof(((struct dirent64*) NULL)->d_reclen));
-        assert_cc(offsetof(struct dirent, d_type) == offsetof(struct dirent64, d_type));
-        assert_cc(sizeof(((struct dirent*) NULL)->d_type) == sizeof(((struct dirent64*) NULL)->d_type));
-        assert_cc(offsetof(struct dirent, d_name) == offsetof(struct dirent64, d_name));
-        assert_cc(sizeof(((struct dirent*) NULL)->d_name) == sizeof(((struct dirent64*) NULL)->d_name));
-
-        /* Start with space for up to 8 directory entries. We expect at least 2 ("." + ".."), hence hopefully
+         * array with readdir_all_freep().
+         *
+         * Start with space for up to 8 directory entries. We expect at least 2 ("." + ".."), hence hopefully
          * 8 will cover most cases comprehensively. (Note that most likely a lot more entries will actually
          * fit in the buffer, given we calculate maximum file name length here.) */
         de = malloc(offsetof(DirectoryEntries, buffer) + DIRENT_SIZE_MAX * 8);