blame: source/misc/embedded_libs/fmt-8.1.1/test/gtest-extra.cc

// Formatting library for C++ - custom Google Test assertions

//

// Copyright (c) 2012 - present, Victor Zverovich

// All rights reserved.

//

// For the license information refer to format.h.

#include "gtest-extra.h"

#if FMT_USE_FCNTL

using fmt::file;

output_redirect::output_redirect(FILE* f) : file_(f) {

  flush();

  int fd = FMT_POSIX(fileno(f));

  // Create a file object referring to the original file.

  original_ = file::dup(fd);

  // Create a pipe.

  file write_end;

  file::pipe(read_end_, write_end);

  // Connect the passed FILE object to the write end of the pipe.

  write_end.dup2(fd);

}

output_redirect::~output_redirect() FMT_NOEXCEPT {

  try {

    restore();

  } catch (const std::exception& e) {

    std::fputs(e.what(), stderr);

  }

}

void output_redirect::flush() {

  int result = 0;

  do {

    result = fflush(file_);

  } while (result == EOF && errno == EINTR);

  if (result != 0) throw fmt::system_error(errno, "cannot flush stream");

}

void output_redirect::restore() {

  if (original_.descriptor() == -1) return;  // Already restored.

  flush();

  // Restore the original file.

  original_.dup2(FMT_POSIX(fileno(file_)));

  original_.close();

}

std::string output_redirect::restore_and_read() {

  // Restore output.

  restore();

  // Read everything from the pipe.

  std::string content;

  if (read_end_.descriptor() == -1) return content;  // Already read.

  enum { BUFFER_SIZE = 4096 };

  char buffer[BUFFER_SIZE];

  size_t count = 0;

  do {

    count = read_end_.read(buffer, BUFFER_SIZE);

    content.append(buffer, count);

  } while (count != 0);

  read_end_.close();

  return content;

}

std::string read(file& f, size_t count) {

  std::string buffer(count, '\0');

  size_t n = 0, offset = 0;

  do {

    n = f.read(&buffer[offset], count - offset);

    // We can't read more than size_t bytes since count has type size_t.

    offset += n;

  } while (offset < count && n != 0);

  buffer.resize(offset);

  return buffer;

}

#endif  // FMT_USE_FCNTL