New error variant and fixed nits

ctru-rs/examples/camera-image.rs

@@ -119,9 +119,10 @@ fn rotate_image_to_screen(src: &[u8], framebuf: *mut u8, width: usize, height: u
             let draw_index = (draw_x * height + draw_y) * 2; // This 2 stands for the number of bytes per pixel (16 bits)
 
             unsafe {
+                // We'll work with pointers since the frambuffer is a raw pointer regardless.
+                // The offsets are completely safe as long as the width and height are correct.
                 let pixel_pointer = framebuf.offset(draw_index as isize);
-                *pixel_pointer = src[read_index];
+                pixel_pointer.copy_from(src.as_ptr().offset(read_index as isize), 2);
-                *pixel_pointer.offset(1) = src[read_index + 1];
             }
         }
     }

ctru-rs/src/error.rs

@@ -55,6 +55,8 @@ pub enum Error {
     Libc(String),
     ServiceAlreadyActive,
     OutputAlreadyRedirected,
+    /// The first member is the length of the buffer provided by the user, the second parameter is the size of the requested data (in bytes).
+    BufferTooShort(usize, usize),
 }
 
 impl Error {
@@ -101,6 +103,7 @@ impl fmt::Debug for Error {
             Self::Libc(err) => f.debug_tuple("Libc").field(err).finish(),
             Self::ServiceAlreadyActive => f.debug_tuple("ServiceAlreadyActive").finish(),
             Self::OutputAlreadyRedirected => f.debug_tuple("OutputAlreadyRedirected").finish(),
+            Self::BufferTooShort(provided, wanted) => f.debug_tuple("BufferTooShort").field(provided).field(wanted).finish(),
         }
     }
 }
@@ -110,7 +113,7 @@ impl fmt::Display for Error {
         match self {
             &Self::Os(err) => write!(
                 f,
-                "libctru result code 0x{err:08X}: [{} {}] {}: {}",
+                "Libctru result code 0x{err:08X}: [{} {}] {}: {}",
                 result_code_level_str(err),
                 result_code_module_str(err),
                 result_code_summary_str(err),
@@ -119,8 +122,9 @@ impl fmt::Display for Error {
             Self::Libc(err) => write!(f, "{err}"),
             Self::ServiceAlreadyActive => write!(f, "Service already active"),
             Self::OutputAlreadyRedirected => {
-                write!(f, "output streams are already redirected to 3dslink")
+                write!(f, "Output streams are already redirected to 3dslink")
             }
+            Self::BufferTooShort(provided, wanted) => write!(f, "The provided buffer's length is too short (length = {provided}) to hold the wanted data (size = {wanted})")
         }
     }
 }

ctru-rs/src/services/cam.rs

@@ -3,7 +3,7 @@
 //! The CAM service provides access to the cameras. Cameras can return 2D images
 //! in the form of byte vectors which can be used for display or other usages.
 
-use crate::error::ResultCode;
+use crate::error::{Error, ResultCode};
 use crate::services::gspgpu::FramebufferFormat;
 use bitflags::bitflags;
 use ctru_sys::Handle;
@@ -710,10 +710,6 @@ pub trait Camera {
     ///
     /// This will error if the camera is busy or if the timeout duration is reached.
     ///
-    /// # Panics
-    ///
-    /// This function will panic if `buffer.len() < (width * height * 2)`.
-    ///
     /// # Arguments
     ///
     /// * `width` - Width of the desired image
@@ -745,9 +741,9 @@ pub trait Camera {
             ))?;
         };
 
-        let screen_size = u32::from(width) * u32::from(height) * 2;
+        let screen_size: usize = usize::from(width) * usize::from(height) * 2;
         if buffer.len() < screen_size as usize {
-            panic!("Provided buffer's length is shorter than the desired width and height matrix.")
+            return Err(Error::BufferTooShort(buffer.len(), screen_size))
         }
 
         unsafe {
@@ -760,9 +756,9 @@ pub trait Camera {
             let mut completion_handle: Handle = 0;
             ResultCode(ctru_sys::CAMU_SetReceiving(
                 &mut completion_handle,
-                buffer.as_mut_ptr() as *mut ::libc::c_void,
+                buffer.as_mut_ptr().cast(),
                 self.port_as_raw(),
-                screen_size,
+                screen_size as u32,
                 transfer_unit.try_into().unwrap(),
             ))?;
             Ok::<Handle, i32>(completion_handle)