1 files changed, 62 insertions, 0 deletions
diff --git a/stdlib/tst-getenv-thread.c b/stdlib/tst-getenv-thread.c
new file mode 100644
index 0000000..2668ae1
--- /dev/null
+++ b/stdlib/tst-getenv-thread.c
@@ -0,0 +1,62 @@
+/* Test getenv with concurrent setenv.
+   Copyright (C) 2024 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <support/check.h>
+#include <support/xthread.h>
+
+/* Set to false by the main thread after doing all the setenv
+   calls.  */
+static bool running = true;
+
+/* Used to synchronize the start of the getenv thread.  */
+static pthread_barrier_t barrier;
+
+/* Invoke getenv for a nonexisting environment variable in a loop.
+   This checks that concurrent setenv does not invalidate the
+   environment array while getenv reads it.  */
+static void *
+getenv_thread (void *ignored)
+{
+  xpthread_barrier_wait (&barrier);
+  while (__atomic_load_n (&running, __ATOMIC_RELAXED))
+    TEST_VERIFY (getenv ("unset_variable") == NULL);
+  return NULL;
+}
+
+static int
+do_test (void)
+{
+  xpthread_barrier_init (&barrier, NULL, 2);
+  pthread_t thr = xpthread_create (NULL, getenv_thread, NULL);
+  xpthread_barrier_wait (&barrier);
+  for (int i = 0; i < 1000; ++i)
+    {
+      char buf[30];
+      snprintf (buf, sizeof (buf), "V%d", i);
+      TEST_COMPARE (setenv (buf, buf + 1, 1), 0);
+    }
+  __atomic_store_n (&running, false, __ATOMIC_RELAXED);
+  xpthread_join (thr);
+  xpthread_barrier_destroy (&barrier);
+  return 0;
+}
+
+#include <support/test-driver.c>