// Formatting library for C++ - tests of the C++ interface to POSIX functions
//
// Copyright (c) 2012 - present, Victor Zverovich
// All rights reserved.
//
// For the license information refer to format.h.

#include <cstdlib>  // std::exit
#include <cstring>
#include <memory>

#include "fmt/posix.h"
#include "gtest-extra.h"
#include "util.h"

#ifdef fileno
#  undef fileno
#endif

using fmt::buffered_file;
using fmt::error_code;
using fmt::file;

// Checks if the file is open by reading one character from it.
static bool isopen(int fd) {
  char buffer;
  return FMT_POSIX(read(fd, &buffer, 1)) == 1;
}

static bool isclosed(int fd) {
  char buffer;
  std::streamsize result = 0;
  SUPPRESS_ASSERT(result = FMT_POSIX(read(fd, &buffer, 1)));
  return result == -1 && errno == EBADF;
}

// Opens a file for reading.
static file open_file() {
  file read_end, write_end;
  file::pipe(read_end, write_end);
  write_end.write(FILE_CONTENT, std::strlen(FILE_CONTENT));
  write_end.close();
  return read_end;
}

// Attempts to write a string to a file.
static void write(file& f, fmt::string_view s) {
  std::size_t num_chars_left = s.size();
  const char* ptr = s.data();
  do {
    std::size_t count = f.write(ptr, num_chars_left);
    ptr += count;
    // We can't write more than size_t bytes since num_chars_left
    // has type size_t.
    num_chars_left -= count;
  } while (num_chars_left != 0);
}

TEST(BufferedFileTest, DefaultCtor) {
  buffered_file f;
  EXPECT_TRUE(f.get() == nullptr);
}

TEST(BufferedFileTest, MoveCtor) {
  buffered_file bf = open_buffered_file();
  FILE* fp = bf.get();
  EXPECT_TRUE(fp != nullptr);
  buffered_file bf2(std::move(bf));
  EXPECT_EQ(fp, bf2.get());
  EXPECT_TRUE(bf.get() == nullptr);
}

TEST(BufferedFileTest, MoveAssignment) {
  buffered_file bf = open_buffered_file();
  FILE* fp = bf.get();
  EXPECT_TRUE(fp != nullptr);
  buffered_file bf2;
  bf2 = std::move(bf);
  EXPECT_EQ(fp, bf2.get());
  EXPECT_TRUE(bf.get() == nullptr);
}

TEST(BufferedFileTest, MoveAssignmentClosesFile) {
  buffered_file bf = open_buffered_file();
  buffered_file bf2 = open_buffered_file();
  int old_fd = bf2.fileno();
  bf2 = std::move(bf);
  EXPECT_TRUE(isclosed(old_fd));
}

TEST(BufferedFileTest, MoveFromTemporaryInCtor) {
  FILE* fp = nullptr;
  buffered_file f(open_buffered_file(&fp));
  EXPECT_EQ(fp, f.get());
}

TEST(BufferedFileTest, MoveFromTemporaryInAssignment) {
  FILE* fp = nullptr;
  buffered_file f;
  f = open_buffered_file(&fp);
  EXPECT_EQ(fp, f.get());
}

TEST(BufferedFileTest, MoveFromTemporaryInAssignmentClosesFile) {
  buffered_file f = open_buffered_file();
  int old_fd = f.fileno();
  f = open_buffered_file();
  EXPECT_TRUE(isclosed(old_fd));
}

TEST(BufferedFileTest, CloseFileInDtor) {
  int fd = 0;
  {
    buffered_file f = open_buffered_file();
    fd = f.fileno();
  }
  EXPECT_TRUE(isclosed(fd));
}

TEST(BufferedFileTest, CloseErrorInDtor) {
  std::unique_ptr<buffered_file> f(new buffered_file(open_buffered_file()));
  EXPECT_WRITE(stderr,
               {
                 // The close function must be called inside EXPECT_WRITE,
                 // otherwise the system may recycle closed file descriptor when
                 // redirecting the output in EXPECT_STDERR and the second close
                 // will break output redirection.
                 FMT_POSIX(close(f->fileno()));
                 SUPPRESS_ASSERT(f.reset(nullptr));
               },
               format_system_error(EBADF, "cannot close file") + "\n");
}

TEST(BufferedFileTest, Close) {
  buffered_file f = open_buffered_file();
  int fd = f.fileno();
  f.close();
  EXPECT_TRUE(f.get() == nullptr);
  EXPECT_TRUE(isclosed(fd));
}

TEST(BufferedFileTest, CloseError) {
  buffered_file f = open_buffered_file();
  FMT_POSIX(close(f.fileno()));
  EXPECT_SYSTEM_ERROR_NOASSERT(f.close(), EBADF, "cannot close file");
  EXPECT_TRUE(f.get() == nullptr);
}

TEST(BufferedFileTest, Fileno) {
  buffered_file f;
#ifndef __COVERITY__
  // fileno on a null FILE pointer either crashes or returns an error.
  // Disable Coverity because this is intentional.
  EXPECT_DEATH_IF_SUPPORTED(
      {
        try {
          f.fileno();
        } catch (const fmt::system_error&) {
          std::exit(1);
        }
      },
      "");
#endif
  f = open_buffered_file();
  EXPECT_TRUE(f.fileno() != -1);
  file copy = file::dup(f.fileno());
  EXPECT_READ(copy, FILE_CONTENT);
}

TEST(FileTest, DefaultCtor) {
  file f;
  EXPECT_EQ(-1, f.descriptor());
}

TEST(FileTest, OpenBufferedFileInCtor) {
  FILE* fp = safe_fopen("test-file", "w");
  std::fputs(FILE_CONTENT, fp);
  std::fclose(fp);
  file f("test-file", file::RDONLY);
  ASSERT_TRUE(isopen(f.descriptor()));
}

TEST(FileTest, OpenBufferedFileError) {
  EXPECT_SYSTEM_ERROR(file("nonexistent", file::RDONLY), ENOENT,
                      "cannot open file nonexistent");
}

TEST(FileTest, MoveCtor) {
  file f = open_file();
  int fd = f.descriptor();
  EXPECT_NE(-1, fd);
  file f2(std::move(f));
  EXPECT_EQ(fd, f2.descriptor());
  EXPECT_EQ(-1, f.descriptor());
}

TEST(FileTest, MoveAssignment) {
  file f = open_file();
  int fd = f.descriptor();
  EXPECT_NE(-1, fd);
  file f2;
  f2 = std::move(f);
  EXPECT_EQ(fd, f2.descriptor());
  EXPECT_EQ(-1, f.descriptor());
}

TEST(FileTest, MoveAssignmentClosesFile) {
  file f = open_file();
  file f2 = open_file();
  int old_fd = f2.descriptor();
  f2 = std::move(f);
  EXPECT_TRUE(isclosed(old_fd));
}

static file OpenBufferedFile(int& fd) {
  file f = open_file();
  fd = f.descriptor();
  return f;
}

TEST(FileTest, MoveFromTemporaryInCtor) {
  int fd = 0xdead;
  file f(OpenBufferedFile(fd));
  EXPECT_EQ(fd, f.descriptor());
}

TEST(FileTest, MoveFromTemporaryInAssignment) {
  int fd = 0xdead;
  file f;
  f = OpenBufferedFile(fd);
  EXPECT_EQ(fd, f.descriptor());
}

TEST(FileTest, MoveFromTemporaryInAssignmentClosesFile) {
  int fd = 0xdead;
  file f = open_file();
  int old_fd = f.descriptor();
  f = OpenBufferedFile(fd);
  EXPECT_TRUE(isclosed(old_fd));
}

TEST(FileTest, CloseFileInDtor) {
  int fd = 0;
  {
    file f = open_file();
    fd = f.descriptor();
  }
  EXPECT_TRUE(isclosed(fd));
}

TEST(FileTest, CloseErrorInDtor) {
  std::unique_ptr<file> f(new file(open_file()));
  EXPECT_WRITE(stderr,
               {
                 // The close function must be called inside EXPECT_WRITE,
                 // otherwise the system may recycle closed file descriptor when
                 // redirecting the output in EXPECT_STDERR and the second close
                 // will break output redirection.
                 FMT_POSIX(close(f->descriptor()));
                 SUPPRESS_ASSERT(f.reset(nullptr));
               },
               format_system_error(EBADF, "cannot close file") + "\n");
}

TEST(FileTest, Close) {
  file f = open_file();
  int fd = f.descriptor();
  f.close();
  EXPECT_EQ(-1, f.descriptor());
  EXPECT_TRUE(isclosed(fd));
}

TEST(FileTest, CloseError) {
  file f = open_file();
  FMT_POSIX(close(f.descriptor()));
  EXPECT_SYSTEM_ERROR_NOASSERT(f.close(), EBADF, "cannot close file");
  EXPECT_EQ(-1, f.descriptor());
}

TEST(FileTest, Read) {
  file f = open_file();
  EXPECT_READ(f, FILE_CONTENT);
}

TEST(FileTest, ReadError) {
  file f("test-file", file::WRONLY);
  char buf;
  // We intentionally read from a file opened in the write-only mode to
  // cause error.
  EXPECT_SYSTEM_ERROR(f.read(&buf, 1), EBADF, "cannot read from file");
}

TEST(FileTest, Write) {
  file read_end, write_end;
  file::pipe(read_end, write_end);
  write(write_end, "test");
  write_end.close();
  EXPECT_READ(read_end, "test");
}

TEST(FileTest, WriteError) {
  file f("test-file", file::RDONLY);
  // We intentionally write to a file opened in the read-only mode to
  // cause error.
  EXPECT_SYSTEM_ERROR(f.write(" ", 1), EBADF, "cannot write to file");
}

TEST(FileTest, Dup) {
  file f = open_file();
  file copy = file::dup(f.descriptor());
  EXPECT_NE(f.descriptor(), copy.descriptor());
  EXPECT_EQ(FILE_CONTENT, read(copy, std::strlen(FILE_CONTENT)));
}

#ifndef __COVERITY__
TEST(FileTest, DupError) {
  int value = -1;
  EXPECT_SYSTEM_ERROR_NOASSERT(file::dup(value), EBADF,
                               "cannot duplicate file descriptor -1");
}
#endif

TEST(FileTest, Dup2) {
  file f = open_file();
  file copy = open_file();
  f.dup2(copy.descriptor());
  EXPECT_NE(f.descriptor(), copy.descriptor());
  EXPECT_READ(copy, FILE_CONTENT);
}

TEST(FileTest, Dup2Error) {
  file f = open_file();
  EXPECT_SYSTEM_ERROR_NOASSERT(
      f.dup2(-1), EBADF,
      fmt::format("cannot duplicate file descriptor {} to -1", f.descriptor()));
}

TEST(FileTest, Dup2NoExcept) {
  file f = open_file();
  file copy = open_file();
  error_code ec;
  f.dup2(copy.descriptor(), ec);
  EXPECT_EQ(ec.get(), 0);
  EXPECT_NE(f.descriptor(), copy.descriptor());
  EXPECT_READ(copy, FILE_CONTENT);
}

TEST(FileTest, Dup2NoExceptError) {
  file f = open_file();
  error_code ec;
  SUPPRESS_ASSERT(f.dup2(-1, ec));
  EXPECT_EQ(EBADF, ec.get());
}

TEST(FileTest, Pipe) {
  file read_end, write_end;
  file::pipe(read_end, write_end);
  EXPECT_NE(-1, read_end.descriptor());
  EXPECT_NE(-1, write_end.descriptor());
  write(write_end, "test");
  EXPECT_READ(read_end, "test");
}

TEST(FileTest, Fdopen) {
  file read_end, write_end;
  file::pipe(read_end, write_end);
  int read_fd = read_end.descriptor();
  EXPECT_EQ(read_fd, FMT_POSIX(fileno(read_end.fdopen("r").get())));
}

TEST(FileTest, FdopenError) {
  file f;
  EXPECT_SYSTEM_ERROR_NOASSERT(f.fdopen("r"), EBADF,
                               "cannot associate stream with file descriptor");
}

#ifdef FMT_LOCALE
TEST(LocaleTest, Strtod) {
  fmt::Locale locale;
  const char *start = "4.2", *ptr = start;
  EXPECT_EQ(4.2, locale.strtod(ptr));
  EXPECT_EQ(start + 3, ptr);
}
#endif
