libc/test/src/unistd/readlinkat_test.cpp

   1 //===-- Unittests for readlinkat ------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "src/__support/CPP/string_view.h"
  10 #include "src/errno/libc_errno.h"
  11 #include "src/unistd/readlinkat.h"
  12 #include "src/unistd/symlink.h"
  13 #include "src/unistd/unlink.h"
  14 #include "test/UnitTest/ErrnoSetterMatcher.h"
  15 #include "test/UnitTest/Test.h"
  16
  17 #include <fcntl.h>
  18
  19 namespace cpp = LIBC_NAMESPACE::cpp;
  20
  21 TEST(LlvmLibcReadlinkatTest, CreateAndUnlink) {
  22   using LIBC_NAMESPACE::testing::ErrnoSetterMatcher::Succeeds;
  23   constexpr const char LINK_VAL[] = "readlinkat_test_value";
  24   constexpr const char LINK[] = "testdata/readlinkat.test.link";
  25   libc_errno = 0;
  26
  27   // The test strategy is as follows:
  28   //   1. Create a symlink with value LINK_VAL.
  29   //   2. Read the symlink with readlink. The link value read should be LINK_VAL
  30   //   3. Cleanup the symlink created in step #1.
  31   ASSERT_THAT(LIBC_NAMESPACE::symlink(LINK_VAL, LINK), Succeeds(0));
  32
  33   char buf[sizeof(LINK_VAL)];
  34   ssize_t len = LIBC_NAMESPACE::readlinkat(AT_FDCWD, LINK, buf, sizeof(buf));
  35   ASSERT_EQ(libc_errno, 0);
  36   ASSERT_EQ(cpp::string_view(buf, len), cpp::string_view(LINK_VAL));
  37
  38   ASSERT_THAT(LIBC_NAMESPACE::unlink(LINK), Succeeds(0));
  39 }
  40
  41 TEST(LlvmLibcReadlinkatTest, ReadlinkInNonExistentPath) {
  42   using LIBC_NAMESPACE::testing::ErrnoSetterMatcher::Fails;
  43   char buf[8];
  44   ASSERT_THAT(LIBC_NAMESPACE::readlinkat(AT_FDCWD, "non-existent-link", buf,
  45                                          sizeof(buf)),
  46               Fails(ENOENT));
  47 }