tty.cpp

Go to the documentation of this file.

// -------------------------------------------------------//
//
// SHAMROCK code for hydrodynamics
// Copyright (c) 2021-2026 Timothée David--Cléris <tim.shamrock@proton.me>
// SPDX-License-Identifier: CeCILL Free Software License Agreement v2.1
// Shamrock is licensed under the CeCILL 2.1 License, see LICENSE for more information
//
// -------------------------------------------------------//

 
#include "sham/term/tty.hpp"
#include <cstdio>
#include <utility>
 
#if __has_include(<unistd.h>)
    #include <unistd.h>
#endif
 
#if __has_include(<sys/ioctl.h>)
    #include <sys/ioctl.h>
#endif
 
namespace {

    bool compute_is_a_tty() {
#if __has_include(<unistd.h>)
        return isatty(fileno(stdout));
#else
        return true;
#endif
    }
 
} // namespace
 
namespace sham::term {
 
    bool is_a_tty() {
        static bool cached = compute_is_a_tty();
        return cached;
    }

    int tty_forced_width = 0;
 
    void set_tty_columns(int columns) { tty_forced_width = columns; }

    std::pair<int, int> get_tty_dim() {
        // If forced width is set, return it
        if (tty_forced_width > 0) {
            return {10, tty_forced_width};
        }
 
        // If the current terminal is not a tty, return a default value
        if (!is_a_tty()) {
            return {10, 100};
        }
 
        // If the terminal is a tty, query its size
#if __has_include(<sys/ioctl.h>) &&  __has_include(<unistd.h>)
        struct winsize w;
        ioctl(STDOUT_FILENO, TIOCGWINSZ, &w);
 
        // If the terminal size is invalid, return a default value
        if (w.ws_col == 0 || w.ws_row == 0) {
            return {10, 100};
        }
        return {w.ws_row, w.ws_col};
#else
        // If the terminal is a tty but we don't have a way to query its size,
        // return a default value
        return {10, 100};
#endif
    }
 
    int get_tty_columns() { return get_tty_dim().second; }
    int get_tty_lines() { return get_tty_dim().first; }

    bool utf8_supported = false;
 
    void set_support_utf8(bool support) { utf8_supported = support; }
    bool support_utf8() { return utf8_supported; }
 
} // namespace sham::term