Scoping out API

CMakeLists.txt

@@ -1,6 +1,34 @@
-cmake_minimum_required(VERSION 3.30)
-project(jstick)
+cmake_minimum_required(VERSION 3.18...3.30)
+project(jstick
+VERSION 1.0
+LANGUAGES CXX)
+
+
+if (PROJECT_SOURCE_DIR STREQUAL PROJECT_BINARY_DIR)
+    message(FATAL_ERROR "In-source builds are not allowed")
+endif()
 
 set(CMAKE_CXX_STANDARD 20)
 
-add_executable(jstick main.cpp)
+file(GLOB_RECURSE jstick_HEADERS "include/*.hpp")
+file(GLOB_RECURSE jstick_SRC "src/*.cpp")
+
+include_directories("include")
+
+if (UNIX)
+    add_library(jstick SHARED ${jstick_SRC})
+endif()
+
+if (WIN32)
+    add_library(jstick STATIC ${jstick_SRC})
+endif()
+
+target_include_directories(jstick PUBLIC ${jstick_SOURCE_DIR}/include)
+
+install(TARGETS ${PROJECT_NAME} DESTINATION lib/${PROJECT_NAME})
+
+install(FILES ${jstick_HEADERS} DESTINATION include/${PROJECT_NAME})
+
+add_executable(jstick-test main.cpp)
+
+target_link_libraries(jstick-test ${PROJECT_NAME})

include/jstick.hpp

@@ -0,0 +1,35 @@
+/// jstick - Dead Simple Game Controller Input Wrapper
+/// Developed and maintained by Josh O'Leary @ Redacted Software
+/// (c) 2025 redacted.cc
+/// This work is dedicated to the public domain.
+
+#pragma once
+
+namespace jstick {
+
+    //Event<int> JoystickConnected;
+    //Event<int> JoystickDisconnected;
+    //Event<JoystickButton> ButtonPressed;
+    //Event<JoystickButton> ButtonReleased;
+    //Event<int, JoystickAxis> AxisMoved;
+
+
+    struct Joystick {
+          int handle;
+
+    };
+
+    struct JoystickAxis {
+        float x;
+        float y;
+    };
+
+    /// Checks the device files for a joystick with the given handle.
+    /// @return True if the joystick device file exists.
+    bool JoystickDetected(int jsHandle = 0);
+    bool HasActiveJoystick();
+    bool InitJoystick(int jsHandle = 0);
+    int NumJoysticksDetected();
+    void JoystickServiceUpdate();
+    void ReadEventLoop();
+}

jstick.hpp

@@ -1,6 +0,0 @@
-#pragma once
-
-
-
-
-void jstick_read_events();

src/jstick.cpp

@@ -0,0 +1,106 @@
+#include <jstick.hpp>
+
+#include <linux/joystick.h>
+#include <cstddef>
+#include <cstdio>
+#include <format>
+#include <filesystem>
+#include <unistd.h>
+#include <bits/fs_fwd.h>
+
+int js_handle;
+bool js_connected;
+
+struct axis_state {
+    short x, y;
+};
+
+/// Reads a joystick event from the joystick device.
+/// @returns 0 on success. Otherwise -1 is returned.
+int read_event(int fd, struct js_event *event) {
+    ssize_t bytes;
+
+    bytes = read(fd, event, sizeof(*event));
+
+    if (bytes == sizeof(*event))
+        return 0;
+
+    /// Error, could not read full event.
+    return -1;
+}
+
+
+bool jstick::JoystickDetected(int jsHandle) {
+    return std::filesystem::exists(std::format("/dev/input/js{}", jsHandle));
+}
+
+int jstick::NumJoysticksDetected() {
+    int max = 4;
+    for (int i = 0; i < max; i++) {
+        if (!JoystickDetected(i))
+            return i;
+    }
+    return max;
+}
+
+
+
+void jstick::JoystickServiceUpdate() {
+    bool has = JoystickDetected();
+
+
+}
+
+void ProcessButtonEvent(uint8_t button_index, bool value) {
+
+}
+
+void ProcessAxisEvent(uint8_t axis, short x, short y) {
+
+}
+
+/// Keeps track of the current axis state.
+/// @note This function assumes that axes are numbered starting from 0, and that
+/// the X axis is an even number, and the Y axis is an odd number. However, this
+/// is usually a safe assumption.
+/// @returns the axis that the event indicated.
+size_t get_axis_state(struct js_event *event, struct axis_state axes[3])
+{
+    size_t axis = event->number / 2;
+
+    if (axis < 3)
+    {
+        if (event->number % 2 == 0)
+            axes[axis].x = event->value;
+        else
+            axes[axis].y = event->value;
+    }
+
+    return axis;
+}
+
+struct js_event event;
+struct axis_state axes[3] = {0};
+size_t axis;
+
+void jstick::ReadEventLoop() {
+
+    while (read_event(js_handle, &event) == 0) {
+        switch (event.type) {
+            case JS_EVENT_BUTTON:
+                ProcessButtonEvent(event.number, event.value ? true : false);
+                break;
+            case JS_EVENT_AXIS:
+                axis = get_axis_state(&event, axes);
+                if (axis < 3)
+                    ProcessAxisEvent(axis, axes[axis].x, axes[axis].y);
+                break;
+            case JS_EVENT_INIT:
+            default:
+                break;
+
+        }
+        fflush(stdout);
+    }
+}
+