1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183

// Copyright 2013-2015, The Gtk-rs Project Developers.
// See the COPYRIGHT file at the top-level directory of this distribution.
// Licensed under the MIT license, see the LICENSE file or <http://opensource.org/licenses/MIT>

use gdk;
use glib;
use glib::translate::*;
use gtk_sys;
use libc::c_uint;
use std::cell::Cell;
use std::ptr;
use std::sync::atomic::{AtomicBool, Ordering, ATOMIC_BOOL_INIT};

#[cfg(target_os = "macos")]
extern "C" {
    fn pthread_main_np() -> i32;
}

thread_local! {
    static IS_MAIN_THREAD: Cell<bool> = Cell::new(false)
}

static INITIALIZED: AtomicBool = ATOMIC_BOOL_INIT;

/// Asserts that this is the main thread and `gtk::init` has been called.
macro_rules! assert_initialized_main_thread {
    () => {
        if !::rt::is_initialized_main_thread() {
            if ::rt::is_initialized() {
                panic!("GTK may only be used from the main thread.");
            } else {
                panic!("GTK has not been initialized. Call `gtk::init` first.");
            }
        }
    };
}

/// No-op.
macro_rules! skip_assert_initialized {
    () => {};
}

/// Asserts that `gtk::init` has not been called.
#[allow(unused_macros)]
macro_rules! assert_not_initialized {
    () => {
        if ::rt::is_initialized() {
            panic!("This function has to be called before `gtk::init`.");
        }
    };
}

/// Returns `true` if GTK has been initialized.
#[inline]
pub fn is_initialized() -> bool {
    skip_assert_initialized!();
    INITIALIZED.load(Ordering::Acquire)
}

/// Returns `true` if GTK has been initialized and this is the main thread.
#[inline]
pub fn is_initialized_main_thread() -> bool {
    skip_assert_initialized!();
    IS_MAIN_THREAD.with(|c| c.get())
}

/// Informs this crate that GTK has been initialized and the current thread is the main one.
///
/// # Panics
///
/// This function will panic if you attempt to initialise GTK from more than
/// one thread.
///
/// # Safety
///
/// You must only call this if:
///
/// 1. You have initialised the underlying GTK library yourself.
/// 2. You did 1 on the thread with which you are calling this function
/// 3. You ensure that this thread is the main thread for the process.
pub unsafe fn set_initialized() {
    skip_assert_initialized!();
    if is_initialized_main_thread() {
        return;
    } else if is_initialized() {
        panic!("Attempted to initialize GTK from two different threads.");
    }

    //  OS X has its own notion of the main thread and init must be called on that thread.
    #[cfg(target_os = "macos")]
    {
        if pthread_main_np() == 0 {
            panic!("Attempted to initialize GTK on OSX from non-main thread");
        }
    }

    gdk::set_initialized();
    INITIALIZED.store(true, Ordering::Release);
    IS_MAIN_THREAD.with(|c| c.set(true));
}

/// Tries to initialize GTK+.
///
/// Call either this function or [`Application::new`][new] before using any
/// other GTK+ functions.
///
/// [new]: struct.Application.html#method.new
///
/// Note that this function calls `gtk_init_check()` rather than `gtk_init()`,
/// so will not cause the program to terminate if GTK could not be initialized.
/// Instead, an Ok is returned if the windowing system was successfully
/// initialized otherwise an Err is returned.
pub fn init() -> Result<(), glib::BoolError> {
    skip_assert_initialized!();
    if is_initialized_main_thread() {
        return Ok(());
    } else if is_initialized() {
        panic!("Attempted to initialize GTK from two different threads.");
    }
    unsafe {
        if from_glib(gtk_sys::gtk_init_check(ptr::null_mut(), ptr::null_mut())) {
            if !glib::MainContext::default().acquire() {
                return Err(glib_bool_error!("Failed to acquire default main context"));
            }

            set_initialized();
            Ok(())
        } else {
            Err(glib_bool_error!("Failed to initialize GTK"))
        }
    }
}

pub fn main_quit() {
    assert_initialized_main_thread!();
    unsafe {
        if gtk_sys::gtk_main_level() > 0 {
            gtk_sys::gtk_main_quit();
        } else if cfg!(debug_assertions) {
            panic!("Attempted to quit a GTK main loop when none is running.");
        }
    }
}

pub fn get_major_version() -> u32 {
    skip_assert_initialized!();
    unsafe { gtk_sys::gtk_get_major_version() as u32 }
}

pub fn get_minor_version() -> u32 {
    skip_assert_initialized!();
    unsafe { gtk_sys::gtk_get_minor_version() as u32 }
}

pub fn get_micro_version() -> u32 {
    skip_assert_initialized!();
    unsafe { gtk_sys::gtk_get_micro_version() as u32 }
}

pub fn get_binary_age() -> u32 {
    skip_assert_initialized!();
    unsafe { gtk_sys::gtk_get_binary_age() as u32 }
}

pub fn get_interface_age() -> u32 {
    skip_assert_initialized!();
    unsafe { gtk_sys::gtk_get_interface_age() as u32 }
}

pub fn check_version(
    required_major: u32,
    required_minor: u32,
    required_micro: u32,
) -> Option<String> {
    skip_assert_initialized!();
    unsafe {
        from_glib_none(gtk_sys::gtk_check_version(
            required_major as c_uint,
            required_minor as c_uint,
            required_micro as c_uint,
        ))
    }
}