From: Philip Hazelden <philip.hazelden@gmail.com>
Date: Sun, 3 Jul 2022 21:46:16 +0000 (+0100)
Subject: Rename: fix empty 'from' with / in filename.
X-Git-Tag: v2.39-rc1~584^2~2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8a6c0e598937aa26ab061214a08374a708249306;p=thirdparty%2Futil-linux.git

Rename: fix empty 'from' with / in filename.

Previously, if we did e.g.

    rename '' _ ./foo.txt

it would try to rename to ._/foo.txt, because `string_replace` was
passed `s="/foo.txt"` and `from` would match at the front. Now we pass
`s="foo.txt"`.

This doesn't affect the case when `to` contains a slash. In that
situation we'll still place `to` at the very beginning of the path, e.g.

    rename '' _/ ./foo.txt # rename to _/./foo.txt
    rename '' /_ ./foo.txt # rename to /_./foo.txt
---

diff --git a/misc-utils/rename.c b/misc-utils/rename.c
index 9979ab1523..e47359c0d9 100644
--- a/misc-utils/rename.c
+++ b/misc-utils/rename.c
@@ -203,8 +203,13 @@ static int do_file(char *from, char *to, char *s, int verbose, int noact,
 		warn(_("stat of %s failed"), s);
 		return 2;
 	}
-	if (strchr(from, '/') == NULL && strchr(to, '/') == NULL)
+	if (strchr(from, '/') == NULL && strchr(to, '/') == NULL) {
 		file = strrchr(s, '/');
+                /* We're going to search for `from` in `file`. If `from` is
+                   empty, we don't want it to match before the '/'. */
+		if (file != NULL)
+			file++;
+	}
 	if (file == NULL)
 		file = s;
 	if (string_replace(from, to, file, s, &newname) != 0)
diff --git a/tests/expected/rename/subdir b/tests/expected/rename/subdir
index f429602762..684cdb8fa8 100644
--- a/tests/expected/rename/subdir
+++ b/tests/expected/rename/subdir
@@ -27,3 +27,8 @@ renxme/aa
 rename_path_a
 rename_path_b
 rename_path_b/test2
+== empty 'from' ==
+`rename_test' -> `_rename_test'
+`./rename_test' -> `./_rename_test'
+`rename_test' -> `rename_subdir/rename_test'
+`./rename_test' -> `rename_subdir/./rename_test'
diff --git a/tests/ts/rename/subdir b/tests/ts/rename/subdir
index 192c2ff051..f6bd758756 100755
--- a/tests/ts/rename/subdir
+++ b/tests/ts/rename/subdir
@@ -65,4 +65,24 @@ rm -f rename_path_a/test2 rename_path_b/test2
 
 rmdir rename_path_a rename_path_b
 
+echo "== empty 'from' ==" >> $TS_OUTPUT
+
+touch rename_test
+$TS_CMD_RENAME -v '' _ rename_test >> $TS_OUTPUT 2>> $TS_ERRLOG
+rm -f *rename_test
+
+touch rename_test
+$TS_CMD_RENAME -v '' _ ./rename_test >> $TS_OUTPUT 2>> $TS_ERRLOG
+rm -f *rename_test
+
+touch rename_test
+mkdir rename_subdir
+$TS_CMD_RENAME -v '' rename_subdir/ rename_test >> $TS_OUTPUT 2>> $TS_ERRLOG
+rm -rf rename_subdir
+
+touch rename_test
+mkdir rename_subdir
+$TS_CMD_RENAME -v '' rename_subdir/ ./rename_test >> $TS_OUTPUT 2>> $TS_ERRLOG
+rm -rf rename_subdir
+
 ts_finalize