From e91e1c31111e23d3751479f5227e84d73505f6f2 Mon Sep 17 00:00:00 2001
From: Peter Hutterer <peter.hutterer@who-t.net>
Date: Tue, 6 May 2025 17:22:41 +1000
Subject: [PATCH] util: add a tmpdir helper

With the __attribute__(cleanup) helper this makes it simple
enough to provide a tempdir inside a function that is (recursively)
automatically deleted when the variable is deleted.

Part-of: <https://gitlab.freedesktop.org/libinput/libinput/-/merge_requests/1204>
---
 src/util-files.h  | 28 ++++++++++++++++++++++++++++
 test/test-utils.c | 18 ++++++++++++++++++
 2 files changed, 46 insertions(+)

diff --git a/src/util-files.h b/src/util-files.h
index a61358c4..5f10db99 100644
--- a/src/util-files.h
+++ b/src/util-files.h
@@ -113,3 +113,31 @@ char **
 list_files(const char **directories,
 	   const char *suffix,
 	   size_t *nfiles);
+
+struct tmpdir {
+	char *path;
+};
+
+static inline void
+tmpdir_destroy(struct tmpdir *tmpdir)
+{
+	/* String check so we can't accidentally rm -rf */
+	if (tmpdir->path && strstr(tmpdir->path, "tmpdir-")) {
+		rmdir_r(tmpdir->path);
+		free(tmpdir->path);
+	}
+	free(tmpdir);
+}
+
+DEFINE_DESTROY_CLEANUP_FUNC(tmpdir);
+
+static inline struct tmpdir *
+tmpdir_create(const char *basedir)
+{
+	_destroy_(tmpdir) *tmpdir = zalloc(sizeof(*tmpdir));
+	tmpdir->path = strdup_printf("%s/tmpdir-XXXXXX", basedir ? basedir : "/tmp");
+	if (!mkdtemp(tmpdir->path))
+		return NULL;
+
+	return steal(&tmpdir);
+}
diff --git a/test/test-utils.c b/test/test-utils.c
index cbbff6ed..4c746779 100644
--- a/test/test-utils.c
+++ b/test/test-utils.c
@@ -113,6 +113,23 @@ START_TEST(rmdir_r_test)
 }
 END_TEST
 
+START_TEST(tmpdir_test)
+{
+	_autofree_ char *tmpdir_path = NULL;
+	{
+		_destroy_(tmpdir) *tmpdir = tmpdir_create(NULL);
+
+		tmpdir_path = safe_strdup(tmpdir->path);
+
+		_autofree_ char *f1 = strdup_printf("%s/wipeme", tmpdir_path);
+		litest_assert_errno_success(close(open(f1, O_WRONLY | O_CREAT, 0644)));
+	}
+	struct stat st;
+	int rc = stat(tmpdir_path, &st) < 0 ? -errno : 0;
+	litest_assert_int_eq(rc, -ENOENT);
+}
+END_TEST
+
 START_TEST(find_files_test)
 {
 	_autofree_ char *dirname = strdup("/tmp/litest_find_files_test.XXXXXX");
@@ -2445,6 +2462,7 @@ int main(void)
 	ADD_TEST(auto_test);
 	ADD_TEST(mkdir_p_test);
 	ADD_TEST(rmdir_r_test);
+	ADD_TEST(tmpdir_test);
 	ADD_TEST(find_files_test);
 
 	ADD_TEST(array_for_each);