drivers/graphics/graphics-ipc: Nicer version handling of version command

drivers/graphics/driver-graphics/src/lib.rs

@@ -1,5 +1,6 @@
 #![feature(slice_as_array)]
 
+use std::cmp;
 use std::collections::{BTreeMap, HashMap};
 use std::fs::File;
 use std::io::{self, Write};
@@ -18,8 +19,8 @@ pub trait GraphicsAdapter {
     type Framebuffer: Framebuffer;
     type Cursor: CursorFramebuffer;
 
-    fn name(&self) -> [u8;16];
-    fn desc(&self) -> [u8;16];
+    fn name(&self) -> &'static [u8];
+    fn desc(&self) -> &'static [u8];
 
     fn get_cap(&self, cap: u64) -> Result<u64>;
     fn set_client_cap(&self, cap: u64, value: u64) -> Result<()>;
@@ -448,8 +449,17 @@ impl<T: GraphicsAdapter> SchemeSync for GraphicsScheme<T> {
                     payload.version_major = 1;
                     payload.version_minor = 4;
                     payload.version_patchlevel = 0;
-                    payload.name = self.adapter.name();
-                    payload.desc = self.adapter.desc();
+
+                    let name = self.adapter.name();
+                    let name_len = cmp::min(name.len(), payload.name_len);
+                    payload.name[..name_len].copy_from_slice(&name[..name_len]);
+                    payload.name_len = name.len();
+
+                    let desc = self.adapter.desc();
+                    let desc_len = cmp::min(desc.len(), payload.name_len);
+                    payload.desc[..desc_len].copy_from_slice(&desc[..desc_len]);
+                    payload.desc_len = desc.len();
+
                     Ok(size_of::<ipc::DisplayCount>())
                 }
 

drivers/graphics/graphics-ipc/src/v2.rs

@@ -160,7 +160,9 @@ pub mod ipc {
         pub version_minor: u32,
         pub version_patchlevel: u32,
         // FIXME allow variable sized fields
+        pub name_len: usize,
         pub name: [u8; 16],
+        pub desc_len: usize,
         pub desc: [u8; 16],
     }
 

drivers/graphics/vesad/src/scheme.rs

@@ -19,27 +19,25 @@ impl GraphicsAdapter for FbAdapter {
     type Framebuffer = GraphicScreen;
     type Cursor = VesadCursor;
 
-    fn name(&self) -> [u8; 16] {
-        [
-            b'v', b'e', b's', b'a', b'd', 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-        ]
+    fn name(&self) -> &'static [u8] {
+        b"vesad"
     }
 
-    fn desc(&self) -> [u8; 16] {
-        [b'V', b'E', b'S', b'A', 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
+    fn desc(&self) -> &'static [u8] {
+        b"VESA"
     }
 
     fn get_cap(&self, cap: u64) -> syscall::Result<u64> {
         match cap {
             CAP_DUMB_BUFFER => Ok(1),
-            _ => Err(syscall::Error::new(EINVAL))
+            _ => Err(syscall::Error::new(EINVAL)),
         }
     }
 
     fn set_client_cap(&self, cap: u64, _value: u64) -> syscall::Result<()> {
         match cap {
             CLIENT_CAP_CURSOR_PLANE_HOTSPOT => Ok(()),
-            _ => Err(syscall::Error::new(EINVAL))
+            _ => Err(syscall::Error::new(EINVAL)),
         }
     }
 

drivers/graphics/virtio-gpud/src/scheme.rs

@@ -201,22 +201,18 @@ impl<'a> GraphicsAdapter for VirtGpuAdapter<'a> {
     type Framebuffer = VirtGpuFramebuffer<'a>;
     type Cursor = VirtGpuCursor;
 
-    fn name(&self) -> [u8; 16] {
-        [
-            b'v', b'i', b'r', b't', b'i', b'o', b'-', b'g', b'p', b'u', b'd', 0, 0, 0, 0, 0,
-        ]
+    fn name(&self) -> &'static [u8] {
+        b"virtio-gpud"
     }
 
-    fn desc(&self) -> [u8; 16] {
-        [
-            b'V', b'i', b'r', b't', b'I', b'O', b' ', b'G', b'P', b'U', 0, 0, 0, 0, 0, 0,
-        ]
+    fn desc(&self) -> &'static [u8] {
+        b"VirtIO GPU"
     }
 
     fn get_cap(&self, cap: u64) -> syscall::Result<u64> {
         match cap {
             CAP_DUMB_BUFFER => Ok(1),
-            _ => Err(syscall::Error::new(EINVAL))
+            _ => Err(syscall::Error::new(EINVAL)),
         }
     }
 
@@ -224,7 +220,7 @@ impl<'a> GraphicsAdapter for VirtGpuAdapter<'a> {
         match cap {
             // FIXME hide cursor plane unless this client cap is set
             CLIENT_CAP_CURSOR_PLANE_HOTSPOT => Ok(()),
-            _ => Err(syscall::Error::new(EINVAL))
+            _ => Err(syscall::Error::new(EINVAL)),
         }
     }