feat: add GLFW wrapper library

1 files changed, 44 insertions, 0 deletions

diff --git a/glfw/src/init.rs b/glfw/src/init.rs
new file mode 100644
index 0000000..d102db6
--- /dev/null
+++ b/glfw/src/init.rs
@@ -0,0 +1,44 @@
+use crate::util::is_main_thread;
+use crate::{get_glfw_error, Error};
+
+/// Initializes GLFW and returns a initialization token.
+///
+/// # Errors
+/// Will return `Err` if
+/// - The current thread is not the main thread
+/// - A GLFW error occurs
+pub fn initialize() -> Result<Glfw, Error>
+{
+    if !is_main_thread() {
+        return Err(Error::NotInMainThread);
+    }
+
+    // SAFETY: The current thread is the main thread
+    let success = unsafe { crate::ffi::glfwInit() };
+
+    if success == crate::ffi::GLFW_FALSE {
+        get_glfw_error()?;
+    }
+
+    Ok(Glfw { _priv: &() })
+}
+
+/// GLFW initialization token.
+pub struct Glfw
+{
+    /// This field has two purposes
+    /// - To make the struct not constructable without calling [`initialize`].
+    /// - To make the struct `!Send` and `!Sync`.
+    _priv: *const (),
+}
+
+impl Drop for Glfw
+{
+    fn drop(&mut self)
+    {
+        // SAFETY: The current thread cannot be any other thread than the main thread
+        // since the initialize function checks it and the GLFW initialization token is
+        // neither Send or Sync
+        unsafe { crate::ffi::glfwTerminate() };
+    }
+}