1 files changed, 119 insertions, 0 deletions
diff --git a/gnulib-tests/test-readlink.h b/gnulib-tests/test-readlink.h
new file mode 100644
index 0000000..b457fa6
--- /dev/null
+++ b/gnulib-tests/test-readlink.h
@@ -0,0 +1,119 @@
+/* Tests of readlink.
+   Copyright (C) 2009-2022 Free Software Foundation, Inc.
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program 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 General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
+
+/* Written by Eric Blake <ebb9@byu.net>, 2009.  */
+
+/* This file is designed to test both readlink(a,b,c) and
+   readlinkat(AT_FDCWD,a,b,c).  FUNC is the function to test.  Assumes
+   that BASE and ASSERT are already defined, and that appropriate
+   headers are already included.  If PRINT, warn before skipping
+   symlink tests with status 77.  */
+
+static int
+test_readlink (ssize_t (*func) (char const *, char *, size_t), bool print)
+{
+  char buf[80];
+
+  /* Sanity checks of failures.  Mingw lacks symlink, but readlink can
+     still distinguish between various errors.  */
+  memset (buf, 0xff, sizeof buf);
+  errno = 0;
+  ASSERT (func ("no_such", buf, sizeof buf) == -1);
+  ASSERT (errno == ENOENT);
+  errno = 0;
+  ASSERT (func ("no_such/", buf, sizeof buf) == -1);
+  ASSERT (errno == ENOENT);
+  errno = 0;
+  ASSERT (func ("", buf, sizeof buf) == -1);
+  ASSERT (errno == ENOENT || errno == EINVAL);
+  errno = 0;
+  ASSERT (func (".", buf, sizeof buf) == -1);
+  ASSERT (errno == EINVAL);
+  errno = 0;
+  ASSERT (func ("./", buf, sizeof buf) == -1);
+  ASSERT (errno == EINVAL);
+  ASSERT (close (creat (BASE "file", 0600)) == 0);
+  errno = 0;
+  ASSERT (func (BASE "file", buf, sizeof buf) == -1);
+  ASSERT (errno == EINVAL);
+  errno = 0;
+  ASSERT (func (BASE "file/", buf, sizeof buf) == -1);
+  ASSERT (errno == ENOTDIR || errno == EINVAL); /* AIX yields EINVAL */
+
+  /* Now test actual symlinks.  */
+  if (symlink (BASE "dir", BASE "link"))
+    {
+      ASSERT (unlink (BASE "file") == 0);
+      if (print)
+        fputs ("skipping test: symlinks not supported on this file system\n",
+               stderr);
+      return 77;
+    }
+  ASSERT (mkdir (BASE "dir", 0700) == 0);
+  errno = 0;
+  ASSERT (func (BASE "link/", buf, sizeof buf) == -1);
+  ASSERT (errno == EINVAL);
+  ASSERT (symlink (BASE "link", BASE "link2") == 0);
+  errno = 0;
+  ASSERT (func (BASE "link2/", buf, sizeof buf) == -1);
+  ASSERT (errno == EINVAL);
+  ASSERT (unlink (BASE "link2") == 0);
+  ASSERT (symlink (BASE "file", BASE "link2") == 0);
+  errno = 0;
+  ASSERT (func (BASE "link2/", buf, sizeof buf) == -1);
+  ASSERT (errno == ENOTDIR || errno == EINVAL); /* AIX yields EINVAL */
+  ASSERT (unlink (BASE "file") == 0);
+  ASSERT (unlink (BASE "link2") == 0);
+  {
+    /* Up till now, no readlink has been successful, so buf should be
+       unchanged.  */
+    int i;
+    for (i = 0; i < sizeof buf; i++)
+      ASSERT (buf[i] == (char) 0xff);
+  }
+  {
+    size_t len = strlen (BASE "dir");
+    /* When passing too small of a buffer, expect the truncated
+       length, or an ERANGE failure.  However, a size of 0 is not
+       portable enough to test.  */
+    ssize_t result;
+    errno = 0;
+    result = readlink (BASE "link", buf, 1);
+    if (result == -1)
+      {
+        ASSERT (errno == ERANGE);
+        ASSERT (buf[0] == (char) 0xff);
+      }
+    else
+      {
+        ASSERT (result == 1);
+        ASSERT (buf[0] == BASE[0]);
+      }
+    ASSERT (buf[1] == (char) 0xff);
+    ASSERT (func (BASE "link", buf, len) == len);
+    ASSERT (strncmp (buf, BASE "dir", len) == 0);
+    ASSERT (buf[len] == (char) 0xff);
+    ASSERT (func (BASE "link", buf, sizeof buf) == len);
+    ASSERT (strncmp (buf, BASE "dir", len) == 0);
+    /* POSIX says rest of buf is unspecified; but in practice, it is
+       either left alone, or NUL-terminated.  */
+    ASSERT (buf[len] == '\0' || buf[len] == (char) 0xff);
+  }
+  ASSERT (rmdir (BASE "dir") == 0);
+  ASSERT (unlink (BASE "link") == 0);
+
+  return 0;
+}