libc/test/src/stdio/setvbuf_test.cpp

   1 //===-- Unittests for setvbuf ---------------------------------------------===//
   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/stdio/fclose.h"
  10 #include "src/stdio/fopen.h"
  11 #include "src/stdio/fread.h"
  12 #include "src/stdio/fwrite.h"
  13 #include "src/stdio/setvbuf.h"
  14 #include "test/UnitTest/Test.h"
  15
  16 #include "hdr/stdio_macros.h"
  17 #include "src/errno/libc_errno.h"
  18
  19 TEST(LlvmLibcSetvbufTest, SetNBFBuffer) {
  20   // The idea in this test is that we open a file for writing and reading, and
  21   // then set a NBF buffer to the write handle. Since it is NBF, the data
  22   // written using the write handle should be immediately readable by the read
  23   // handle.
  24   constexpr char FILENAME[] = "testdata/setvbuf_nbf.test";
  25
  26   ::FILE *fw = LIBC_NAMESPACE::fopen(FILENAME, "w");
  27   ASSERT_FALSE(fw == nullptr);
  28   char buffer[BUFSIZ];
  29   ASSERT_EQ(LIBC_NAMESPACE::setvbuf(fw, buffer, _IONBF, BUFSIZ), 0);
  30
  31   ::FILE *fr = LIBC_NAMESPACE::fopen(FILENAME, "r");
  32   ASSERT_FALSE(fr == nullptr);
  33
  34   constexpr char CONTENT[] = "abcdef";
  35   constexpr size_t CONTENT_SIZE = sizeof(CONTENT);
  36   for (size_t i = 0; i < CONTENT_SIZE; ++i) {
  37     ASSERT_EQ(size_t(1), LIBC_NAMESPACE::fwrite(CONTENT + i, 1, 1, fw));
  38     char c;
  39     ASSERT_EQ(size_t(1), LIBC_NAMESPACE::fread(&c, 1, 1, fr));
  40     ASSERT_EQ(c, CONTENT[i]);
  41   }
  42
  43   ASSERT_EQ(0, LIBC_NAMESPACE::fclose(fw));
  44   ASSERT_EQ(0, LIBC_NAMESPACE::fclose(fr));
  45
  46   // Make sure NBF buffer has no effect for reading.
  47   fr = LIBC_NAMESPACE::fopen(FILENAME, "r");
  48   char data[CONTENT_SIZE];
  49   ASSERT_EQ(LIBC_NAMESPACE::setvbuf(fr, buffer, _IONBF, BUFSIZ), 0);
  50   ASSERT_EQ(CONTENT_SIZE, LIBC_NAMESPACE::fread(data, 1, CONTENT_SIZE, fr));
  51   ASSERT_STREQ(CONTENT, data);
  52   ASSERT_EQ(0, LIBC_NAMESPACE::fclose(fr));
  53 }
  54
  55 TEST(LlvmLibcSetvbufTest, SetLBFBuffer) {
  56   // The idea in this test is that we open a file for writing and reading, and
  57   // then set a LBF buffer to the write handle. Since it is LBF, the data
  58   // written using the write handle should be available right after a '\n' is
  59   // written.
  60   constexpr char FILENAME[] = "testdata/setvbuf_lbf.test";
  61
  62   ::FILE *fw = LIBC_NAMESPACE::fopen(FILENAME, "w");
  63   ASSERT_FALSE(fw == nullptr);
  64   char buffer[BUFSIZ];
  65   ASSERT_EQ(LIBC_NAMESPACE::setvbuf(fw, buffer, _IOLBF, BUFSIZ), 0);
  66
  67   ::FILE *fr = LIBC_NAMESPACE::fopen(FILENAME, "r");
  68   ASSERT_FALSE(fr == nullptr);
  69
  70   constexpr char CONTENT[] = "abcdef\n";
  71   constexpr size_t CONTENT_SIZE = sizeof(CONTENT);
  72   ASSERT_EQ(CONTENT_SIZE, LIBC_NAMESPACE::fwrite(CONTENT, 1, CONTENT_SIZE, fw));
  73
  74   // Note that CONTENT_SIZE worth of data written also includes the
  75   // null-terminator '\0'. But, since it is after the new line character,
  76   // it should not be availabe for reading.
  77   char data[CONTENT_SIZE];
  78   ASSERT_EQ(CONTENT_SIZE - 1, LIBC_NAMESPACE::fread(data, 1, CONTENT_SIZE, fr));
  79   char c;
  80   ASSERT_EQ(size_t(0), LIBC_NAMESPACE::fread(&c, 1, 1, fr));
  81
  82   data[CONTENT_SIZE - 1] = '\0';
  83   ASSERT_STREQ(CONTENT, data);
  84
  85   ASSERT_EQ(0, LIBC_NAMESPACE::fclose(fw));
  86   ASSERT_EQ(0, LIBC_NAMESPACE::fclose(fr));
  87
  88   // Make sure LBF buffer has no effect for reading.
  89   fr = LIBC_NAMESPACE::fopen(FILENAME, "r");
  90   ASSERT_EQ(LIBC_NAMESPACE::setvbuf(fr, buffer, _IOLBF, BUFSIZ), 0);
  91   ASSERT_EQ(CONTENT_SIZE, LIBC_NAMESPACE::fread(data, 1, CONTENT_SIZE, fr));
  92   ASSERT_STREQ(CONTENT, data);
  93   ASSERT_EQ(0, LIBC_NAMESPACE::fclose(fr));
  94 }
  95
  96 TEST(LlvmLibcSetbufTest, InvalidBufferMode) {
  97   constexpr char FILENAME[] = "testdata/setvbuf_invalid_bufmode.test";
  98   ::FILE *f = LIBC_NAMESPACE::fopen(FILENAME, "w");
  99   ASSERT_FALSE(f == nullptr);
 100   char buf[BUFSIZ];
 101   ASSERT_NE(LIBC_NAMESPACE::setvbuf(f, buf, _IOFBF + _IOLBF + _IONBF, BUFSIZ),
 102             0);
 103   ASSERT_ERRNO_EQ(EINVAL);
 104
 105   LIBC_NAMESPACE::libc_errno = 0;
 106   ASSERT_EQ(0, LIBC_NAMESPACE::fclose(f));
 107 }