libc/test/src/unistd/swab_test.cpp

   1
   2 //===-- Unittests for swab ------------------------------------------------===//
   3 //
   4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   5 // See https://llvm.org/LICENSE.txt for license information.
   6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #include "src/unistd/swab.h"
  11
  12 #include "src/string/string_utils.h"
  13 #include "test/UnitTest/Test.h"
  14
  15 TEST(LlvmLibcSwabTest, NegativeSizeIsNoOp) {
  16   const char *from = "abc";
  17   char to[4] = {'x', 'y', 'z', '\0'};
  18   LIBC_NAMESPACE::swab(from, to, -1);
  19   ASSERT_STREQ(to, "xyz");
  20 }
  21
  22 TEST(LlvmLibcSwabTest, ZeroSizeIsNoOp) {
  23   const char *from = "abc";
  24   char to[4] = {'x', 'y', 'z', '\0'};
  25   LIBC_NAMESPACE::swab(from, to, 0);
  26   ASSERT_STREQ(to, "xyz");
  27 }
  28
  29 TEST(LlvmLibcSwabTest, SingleByteIsNoOp) {
  30   char from[] = {'a'};
  31   char to[4] = {'x', 'y', 'z', '\0'};
  32   LIBC_NAMESPACE::swab(from, to, sizeof(from));
  33   ASSERT_STREQ(to, "xyz");
  34 }
  35
  36 TEST(LlvmLibcSwabTest, NullPtrsAreNotDeRefedIfNIsLessThanTwo) {
  37   // This test passes if a crash does not happen
  38   LIBC_NAMESPACE::swab(nullptr, nullptr, -1);
  39   LIBC_NAMESPACE::swab(nullptr, nullptr, 0);
  40   LIBC_NAMESPACE::swab(nullptr, nullptr, 1);
  41 }
  42
  43 TEST(LlvmLibcSwabTest, BytesAreSwappedWithEvenN) {
  44   {
  45     const char *from = "ab";
  46     char to[3] = {};
  47     LIBC_NAMESPACE::swab(from, to,
  48                          LIBC_NAMESPACE::internal::string_length(from));
  49     ASSERT_STREQ(to, "ba");
  50   }
  51   {
  52     const char *from = "abcd";
  53     char to[5] = {};
  54     LIBC_NAMESPACE::swab(from, to,
  55                          LIBC_NAMESPACE::internal::string_length(from));
  56     ASSERT_STREQ(to, "badc");
  57   }
  58   {
  59     const char *from = "aAaAaA";
  60     char to[7] = {};
  61     LIBC_NAMESPACE::swab(from, to,
  62                          LIBC_NAMESPACE::internal::string_length(from));
  63     ASSERT_STREQ(to, "AaAaAa");
  64   }
  65 }
  66
  67 TEST(LlvmLibcSwabTest, LastByteIgnoredWithOddN) {
  68   {
  69     const char *from = "aba";
  70     char to[3] = {};
  71     LIBC_NAMESPACE::swab(from, to,
  72                          LIBC_NAMESPACE::internal::string_length(from));
  73     ASSERT_STREQ(to, "ba");
  74   }
  75   {
  76     const char *from = "abcde";
  77     char to[5] = {};
  78     LIBC_NAMESPACE::swab(from, to,
  79                          LIBC_NAMESPACE::internal::string_length(from));
  80     ASSERT_STREQ(to, "badc");
  81   }
  82   {
  83     const char *from = "aAaAaAx";
  84     char to[7] = {};
  85     LIBC_NAMESPACE::swab(from, to,
  86                          LIBC_NAMESPACE::internal::string_length(from));
  87     ASSERT_STREQ(to, "AaAaAa");
  88   }
  89 }