Added thirdparty: boost library

thirdparty/include/boost/histogram/detail/term_info.hpp

@@ -0,0 +1,87 @@
+// Copyright 2021 Hans Dembinski
+//
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE_1_0.txt
+// or copy at http://www.boost.org/LICENSE_1_0.txt)
+
+#ifndef BOOST_HISTOGRAM_DETAIL_TERM_INFO_HPP
+#define BOOST_HISTOGRAM_DETAIL_TERM_INFO_HPP
+
+#include <algorithm>
+
+#if defined __has_include
+#if __has_include(<sys/ioctl.h>) && __has_include(<unistd.h>)
+#include <sys/ioctl.h>
+#include <unistd.h>
+#endif
+#endif
+#include <boost/config.hpp>
+#include <cstdlib>
+#include <cstring>
+
+namespace boost {
+namespace histogram {
+namespace detail {
+
+namespace term_info {
+class env_t {
+public:
+  env_t(const char* key) {
+#if defined(BOOST_MSVC) // msvc complains about using std::getenv
+    _dupenv_s(&data_, &size_, key);
+#else
+    data_ = std::getenv(key);
+    if (data_) size_ = std::strlen(data_);
+#endif
+  }
+
+  ~env_t() {
+#if defined(BOOST_MSVC)
+    std::free(data_);
+#endif
+  }
+
+  bool contains(const char* s) {
+    const std::size_t n = std::strlen(s);
+    if (size_ < n) return false;
+    return std::strstr(data_, s);
+  }
+
+  operator bool() { return size_ > 0; }
+
+  explicit operator int() { return size_ ? std::atoi(data_) : 0; }
+
+  const char* data() const { return data_; }
+
+private:
+  char* data_;
+  std::size_t size_ = 0;
+};
+
+inline bool utf8() {
+  // return false only if LANG exists and does not contain the string UTF
+  env_t env("LANG");
+  bool b = true;
+  if (env) b = env.contains("UTF") || env.contains("utf");
+  return b;
+}
+
+inline int width() {
+  int w = 0;
+#if defined TIOCGWINSZ
+  struct winsize ws;
+  ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws);
+  w = (std::max)(static_cast<int>(ws.ws_col), 0); // not sure if ws_col can be less than 0
+#endif
+  env_t env("COLUMNS");
+  const int col = (std::max)(static_cast<int>(env), 0);
+  // if both t and w are set, COLUMNS may be used to restrict width
+  return w == 0 ? col : (std::min)(col, w);
+}
+} // namespace term_info
+
+} // namespace detail
+} // namespace histogram
+} // namespace boost
+
+#endif