libc/test/src/stdio/setbuf_test.cpp

   1 //===-- Unittests for setbuf ----------------------------------------------===//
   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 "hdr/stdio_macros.h"
  10 #include "src/stdio/fclose.h"
  11 #include "src/stdio/fopen.h"
  12 #include "src/stdio/fread.h"
  13 #include "src/stdio/fwrite.h"
  14 #include "src/stdio/setbuf.h"
  15 #include "src/stdio/ungetc.h"
  16 #include "test/UnitTest/Test.h"
  17
  18 TEST(LlvmLibcSetbufTest, DefaultBufsize) {
  19   // The idea in this test is to change the buffer after opening a file and
  20   // ensure that read and write work as expected.
  21   constexpr char FILENAME[] = "testdata/setbuf_test_default_bufsize.test";
  22   ::FILE *file = LIBC_NAMESPACE::fopen(FILENAME, "w");
  23   ASSERT_FALSE(file == nullptr);
  24   char buffer[BUFSIZ];
  25   LIBC_NAMESPACE::setbuf(file, buffer);
  26   constexpr char CONTENT[] = "abcdef";
  27   constexpr size_t CONTENT_SIZE = sizeof(CONTENT);
  28   ASSERT_EQ(CONTENT_SIZE,
  29             LIBC_NAMESPACE::fwrite(CONTENT, 1, CONTENT_SIZE, file));
  30   ASSERT_EQ(0, LIBC_NAMESPACE::fclose(file));
  31
  32   file = LIBC_NAMESPACE::fopen(FILENAME, "r");
  33   LIBC_NAMESPACE::setbuf(file, buffer);
  34   ASSERT_FALSE(file == nullptr);
  35   char data[CONTENT_SIZE];
  36   ASSERT_EQ(LIBC_NAMESPACE::fread(&data, 1, CONTENT_SIZE, file), CONTENT_SIZE);
  37   ASSERT_STREQ(CONTENT, data);
  38   ASSERT_EQ(0, LIBC_NAMESPACE::fclose(file));
  39 }
  40
  41 TEST(LlvmLibcSetbufTest, NullBuffer) {
  42   // The idea in this test is that we set a null buffer and ensure that
  43   // everything works correctly.
  44   constexpr char FILENAME[] = "testdata/setbuf_test_null_buffer.test";
  45   ::FILE *file = LIBC_NAMESPACE::fopen(FILENAME, "w");
  46   ASSERT_FALSE(file == nullptr);
  47   LIBC_NAMESPACE::setbuf(file, nullptr);
  48   constexpr char CONTENT[] = "abcdef";
  49   constexpr size_t CONTENT_SIZE = sizeof(CONTENT);
  50   ASSERT_EQ(CONTENT_SIZE,
  51             LIBC_NAMESPACE::fwrite(CONTENT, 1, CONTENT_SIZE, file));
  52   ASSERT_EQ(0, LIBC_NAMESPACE::fclose(file));
  53
  54   file = LIBC_NAMESPACE::fopen(FILENAME, "r");
  55   LIBC_NAMESPACE::setbuf(file, nullptr);
  56   ASSERT_FALSE(file == nullptr);
  57   char data[CONTENT_SIZE];
  58   ASSERT_EQ(LIBC_NAMESPACE::fread(&data, 1, CONTENT_SIZE, file), CONTENT_SIZE);
  59   ASSERT_STREQ(CONTENT, data);
  60
  61   // Ensure that ungetc also works.
  62   char unget_char = 'z';
  63   ASSERT_EQ(int(unget_char), LIBC_NAMESPACE::ungetc(unget_char, file));
  64   char c;
  65   ASSERT_EQ(LIBC_NAMESPACE::fread(&c, 1, 1, file), size_t(1));
  66   ASSERT_EQ(c, unget_char);
  67
  68   ASSERT_EQ(0, LIBC_NAMESPACE::fclose(file));
  69 }