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/string/string_utils.h"
  12 #include "src/unistd/readlinkat.h"
  13 #include "src/unistd/symlink.h"
  14 #include "src/unistd/unlink.h"
  15 #include "test/UnitTest/ErrnoSetterMatcher.h"
  16 #include "test/UnitTest/Test.h"
  17
  18 #include "hdr/fcntl_macros.h"
  19
  20 namespace cpp = LIBC_NAMESPACE::cpp;
  21
  22 TEST(LlvmLibcReadlinkatTest, CreateAndUnlink) {
  23   using LIBC_NAMESPACE::testing::ErrnoSetterMatcher::Succeeds;
  24   constexpr const char *FILENAME = "readlinkat_test_file";
  25   auto LINK_VAL = libc_make_test_file_path(FILENAME);
  26   constexpr const char *FILENAME2 = "readlinkat_test_file.link";
  27   auto LINK = libc_make_test_file_path(FILENAME2);
  28   LIBC_NAMESPACE::libc_errno = 0;
  29
  30   // The test strategy is as follows:
  31   //   1. Create a symlink with value LINK_VAL.
  32   //   2. Read the symlink with readlink. The link value read should be LINK_VAL
  33   //   3. Cleanup the symlink created in step #1.
  34   ASSERT_THAT(LIBC_NAMESPACE::symlink(LINK_VAL, LINK), Succeeds(0));
  35
  36   char buf[256];
  37   ssize_t len = LIBC_NAMESPACE::readlinkat(
  38       AT_FDCWD, LINK, buf, LIBC_NAMESPACE::internal::string_length(FILENAME));
  39   ASSERT_ERRNO_SUCCESS();
  40   ASSERT_EQ(cpp::string_view(buf, len), cpp::string_view(LINK_VAL));
  41
  42   ASSERT_THAT(LIBC_NAMESPACE::unlink(LINK), Succeeds(0));
  43 }
  44
  45 TEST(LlvmLibcReadlinkatTest, ReadlinkInNonExistentPath) {
  46   using LIBC_NAMESPACE::testing::ErrnoSetterMatcher::Fails;
  47   constexpr auto LEN = 8;
  48   char buf[LEN];
  49   ASSERT_THAT(
  50       LIBC_NAMESPACE::readlinkat(AT_FDCWD, "non-existent-link", buf, LEN),
  51       Fails(ENOENT));
  52 }