libc/test/src/pwd/getpwnam_r_test.cpp

//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
///
/// \file
/// Unit tests for getpwnam_r.
///
//===----------------------------------------------------------------------===//

#include "hdr/errno_macros.h"
#include "hdr/types/gid_t.h"
#include "hdr/types/size_t.h"
#include "hdr/types/struct_passwd.h"
#include "hdr/types/uid_t.h"
#include "pwd_test_utils.h"
#include "src/pwd/getpwnam_r.h"
#include "src/pwd/pwd_utils.h"
#include "test/UnitTest/Test.h"

using LlvmLibcGetpwnamRTest = LlvmLibcPwdTest;

TEST_F(LlvmLibcGetpwnamRTest, Success) {
  const char *content = "root:x:0:0:root:/root:/bin/bash\n"
                        "bin:x:1:1:bin:/bin:/sbin/nologin\n"
                        "daemon:x:2:2:daemon:/sbin:/sbin/nologin\n";
  ScopedPasswdFile test_file(
      libc_make_test_file_path("getpwnam_r_success.test"), content);

  struct passwd pwd;
  char buffer[256];
  struct passwd *result = nullptr;

  ASSERT_EQ(
      LIBC_NAMESPACE::getpwnam_r("bin", &pwd, buffer, sizeof(buffer), &result),
      0);
  ASSERT_EQ(result, &pwd);
  ASSERT_STREQ(pwd.pw_name, "bin");
  ASSERT_STREQ(pwd.pw_passwd, "x");
  ASSERT_EQ(pwd.pw_uid, static_cast<uid_t>(1));
  ASSERT_EQ(pwd.pw_gid, static_cast<gid_t>(1));
  ASSERT_STREQ(pwd.pw_gecos, "bin");
  ASSERT_STREQ(pwd.pw_dir, "/bin");
  ASSERT_STREQ(pwd.pw_shell, "/sbin/nologin");
}

TEST_F(LlvmLibcGetpwnamRTest, FirstAndLastEntries) {
  const char *content = "first:x:100:100:first:/home/first:/bin/sh\n"
                        "middle:x:101:101:middle:/home/middle:/bin/sh\n"
                        "last:x:102:102:last:/home/last:/bin/sh\n";
  ScopedPasswdFile test_file(
      libc_make_test_file_path("getpwnam_r_boundary.test"), content);

  struct passwd pwd;
  char buffer[256];
  struct passwd *result = nullptr;

  // Lookup the first entry
  ASSERT_EQ(LIBC_NAMESPACE::getpwnam_r("first", &pwd, buffer, sizeof(buffer),
                                       &result),
            0);
  ASSERT_EQ(result, &pwd);
  ASSERT_STREQ(pwd.pw_name, "first");
  ASSERT_EQ(pwd.pw_uid, static_cast<uid_t>(100));

  // Lookup the last entry
  result = nullptr;
  ASSERT_EQ(
      LIBC_NAMESPACE::getpwnam_r("last", &pwd, buffer, sizeof(buffer), &result),
      0);
  ASSERT_EQ(result, &pwd);
  ASSERT_STREQ(pwd.pw_name, "last");
  ASSERT_EQ(pwd.pw_uid, static_cast<uid_t>(102));
}

TEST_F(LlvmLibcGetpwnamRTest, NotFound) {
  const char *content = "root:x:0:0:root:/root:/bin/bash\n";
  ScopedPasswdFile test_file(
      libc_make_test_file_path("getpwnam_r_notfound.test"), content);

  struct passwd pwd;
  char buffer[256];
  struct passwd *result = reinterpret_cast<struct passwd *>(0xdeadbeef);

  ASSERT_EQ(LIBC_NAMESPACE::getpwnam_r("nonexistent", &pwd, buffer,
                                       sizeof(buffer), &result),
            0);
  ASSERT_EQ(result, static_cast<struct passwd *>(nullptr));
}

TEST_F(LlvmLibcGetpwnamRTest, BufferTooSmall) {
  const char *content = "root:x:0:0:root:/root:/bin/bash\n";
  ScopedPasswdFile test_file(
      libc_make_test_file_path("getpwnam_r_toosmall.test"), content);

  struct passwd pwd;
  char small_buf[8];
  struct passwd *result = reinterpret_cast<struct passwd *>(0xdeadbeef);

  ASSERT_EQ(LIBC_NAMESPACE::getpwnam_r("root", &pwd, small_buf,
                                       sizeof(small_buf), &result),
            ERANGE);
  ASSERT_EQ(result, static_cast<struct passwd *>(nullptr));

  // Single-byte buffer is insufficient and must return ERANGE.
  char tiny_buf[1];
  result = reinterpret_cast<struct passwd *>(0xdeadbeef);
  ASSERT_EQ(LIBC_NAMESPACE::getpwnam_r("root", &pwd, tiny_buf, sizeof(tiny_buf),
                                       &result),
            ERANGE);
  ASSERT_EQ(result, static_cast<struct passwd *>(nullptr));

  // Zero-byte buffer is insufficient and must return ERANGE.
  result = reinterpret_cast<struct passwd *>(0xdeadbeef);
  ASSERT_EQ(LIBC_NAMESPACE::getpwnam_r("root", &pwd, small_buf, 0, &result),
            ERANGE);
  ASSERT_EQ(result, static_cast<struct passwd *>(nullptr));

  // Note: passing nullptr for name, pwd, buffer, or result is undefined
  // behavior per POSIX. The implementation uses LIBC_CRASH_ON_NULLPTR for each
  // pointer, so there are no nullptr tests here in hermetic unit tests.
}

TEST_F(LlvmLibcGetpwnamRTest, BlankLines) {
  const char *content = "\nroot:x:0:0:root:/root:/bin/bash\n\n\n"
                        "bin:x:1:1:bin:/bin:/sbin/nologin\n\n";
  ScopedPasswdFile test_file(libc_make_test_file_path("getpwnam_r_blank.test"),
                             content);

  struct passwd pwd;
  char buffer[256];
  struct passwd *result = nullptr;

  ASSERT_EQ(
      LIBC_NAMESPACE::getpwnam_r("bin", &pwd, buffer, sizeof(buffer), &result),
      0);
  ASSERT_EQ(result, &pwd);
  ASSERT_STREQ(pwd.pw_name, "bin");
  ASSERT_EQ(pwd.pw_uid, static_cast<uid_t>(1));
}