fix: Replace C-style casts with C++ casts

This commit addresses cppcheck warnings about C-style casts (cstyleCast)
by replacing them with appropriate C++ casts. C-style casts are considered
dangerous because they can perform unsafe conversions without compile-time
type checking, while C++ casts are more explicit and type-safe.

Changes made:
- static_cast for safe type conversions (e.g., void* to struct*)
- reinterpret_cast for pointer type conversions (e.g., uint8_t* to char*)
- Combined static_cast and reinterpret_cast for integer-to-pointer conversions

Fixed files:
- kmscube/cube-gles2.cpp: GLvoid* casts for OpenGL vertex attribute pointers
- kmscube/cube-wl.cpp: Wayland interface pointer casts
- kmscube/cube-x11.cpp: X11 window handle conversion
- utils/fbtest.cpp: mmap return value cast
- utils/kmstest.cpp: Framebuffer pointer arithmetic
- utils/kmsview.cpp: Framebuffer memory mapping cast

3 files changed, 7 insertions, 7 deletions

diff --git a/kmscube/cube-gles2.cpp b/kmscube/cube-gles2.cpp
index 854c90e..0e52a32 100644
--- a/kmscube/cube-gles2.cpp
+++ b/kmscube/cube-gles2.cpp
@@ -200,11 +200,11 @@ GlScene::GlScene()
 	glBufferSubData(GL_ARRAY_BUFFER, positionsoffset, sizeof(vVertices), &vVertices[0]);
 	glBufferSubData(GL_ARRAY_BUFFER, colorsoffset, sizeof(vColors), &vColors[0]);
 	glBufferSubData(GL_ARRAY_BUFFER, normalsoffset, sizeof(vNormals), &vNormals[0]);
-	glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, (const GLvoid*)positionsoffset);
+	glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, reinterpret_cast<const GLvoid*>(positionsoffset));
 	glEnableVertexAttribArray(0);
-	glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 0, (const GLvoid*)normalsoffset);
+	glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 0, reinterpret_cast<const GLvoid*>(normalsoffset));
 	glEnableVertexAttribArray(1);
-	glVertexAttribPointer(2, 3, GL_FLOAT, GL_FALSE, 0, (const GLvoid*)colorsoffset);
+	glVertexAttribPointer(2, 3, GL_FLOAT, GL_FALSE, 0, reinterpret_cast<const GLvoid*>(colorsoffset));
 	glEnableVertexAttribArray(2);
 }
 
diff --git a/kmscube/cube-wl.cpp b/kmscube/cube-wl.cpp
index 136a4ed..95ad5c3 100644
--- a/kmscube/cube-wl.cpp
+++ b/kmscube/cube-wl.cpp
@@ -23,9 +23,9 @@ struct window {
 static void registry_add_object(void* data, struct wl_registry* registry, uint32_t name, const char* interface, uint32_t version)
 {
 	if (!strcmp(interface, "wl_compositor"))
-		s_compositor = (struct wl_compositor*)wl_registry_bind(registry, name, &wl_compositor_interface, 0);
+		s_compositor = static_cast<struct wl_compositor*>(wl_registry_bind(registry, name, &wl_compositor_interface, 0));
 	else if (!strcmp(interface, "wl_shell"))
-		s_shell = (struct wl_shell*)wl_registry_bind(registry, name, &wl_shell_interface, 0);
+		s_shell = static_cast<struct wl_shell*>(wl_registry_bind(registry, name, &wl_shell_interface, 0));
 }
 
 static void registry_remove_object(void* data, struct wl_registry* registry, uint32_t name)
@@ -41,7 +41,7 @@ static void shell_surface_ping(void* data, struct wl_shell_surface* shell_surfac
 
 static void shell_surface_configure(void* data, struct wl_shell_surface* shell_surface, uint32_t edges, int32_t width, int32_t height)
 {
-	struct window* window = (struct window*)data;
+	struct window* window = static_cast<struct window*>(data);
 
 	wl_egl_window_resize(window->egl_window, width, height, 0, 0);
 }
diff --git a/kmscube/cube-x11.cpp b/kmscube/cube-x11.cpp
index ae018ea..eb57616 100644
--- a/kmscube/cube-x11.cpp
+++ b/kmscube/cube-x11.cpp
@@ -13,7 +13,7 @@ using namespace std;
 static void main_loop(Display* dpy, xcb_connection_t* c, xcb_window_t window, uint32_t width, uint32_t height)
 {
 	EglState egl(dpy);
-	EglSurface surface(egl, (void*)(uintptr_t)window);
+	EglSurface surface(egl, reinterpret_cast<void*>(static_cast<uintptr_t>(window)));
 	GlScene scene;
 
 	scene.set_viewport(width, height);