rust: do not use --generate-cstr

--generate-cstr is a good idea and generally the right thing to do,
but it is not available in Debian 12 and Ubuntu 22.04.  Work around
the absence.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

meson.build

@@ -3961,13 +3961,15 @@ common_all = static_library('common',
                             dependencies: common_ss.all_dependencies())
 
 if have_rust
+  # We would like to use --generate-cstr, but it is only available
+  # starting with bindgen 0.66.0.  The oldest supported versions
+  # are in Ubuntu 22.04 (0.59.1) and Debian 12 (0.60.1).
   bindgen_args = [
     '--disable-header-comment',
     '--raw-line', '// @generated',
     '--ctypes-prefix', 'std::os::raw',
     '--formatter', 'rustfmt',
     '--generate-block',
-    '--generate-cstr',
     '--impl-debug',
     '--merge-extern-blocks',
     '--no-doc-comments',

rust/hw/char/pl011/src/device.rs

@@ -12,6 +12,7 @@ use qemu_api::{
     bindings::{self, *},
     c_str,
     definitions::ObjectImpl,
+    device_class::TYPE_SYS_BUS_DEVICE,
 };
 
 use crate::{

rust/qemu-api/src/device_class.rs

@@ -2,6 +2,10 @@
 // Author(s): Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
 // SPDX-License-Identifier: GPL-2.0-or-later
 
+use std::ffi::CStr;
+
+use crate::bindings;
+
 #[macro_export]
 macro_rules! device_class_init {
     ($func:ident, props => $props:ident, realize_fn => $realize_fn:expr, legacy_reset_fn => $legacy_reset_fn:expr, vmsd => $vmsd:ident$(,)*) => {
@@ -62,3 +66,9 @@ macro_rules! declare_properties {
         ];
     };
 }
+
+// workaround until we can use --generate-cstr in bindgen.
+pub const TYPE_DEVICE: &CStr =
+    unsafe { CStr::from_bytes_with_nul_unchecked(bindings::TYPE_DEVICE) };
+pub const TYPE_SYS_BUS_DEVICE: &CStr =
+    unsafe { CStr::from_bytes_with_nul_unchecked(bindings::TYPE_SYS_BUS_DEVICE) };

rust/qemu-api/tests/tests.rs

@@ -8,7 +8,7 @@ use qemu_api::{
     bindings::*,
     c_str, declare_properties, define_property,
     definitions::{Class, ObjectImpl},
-    device_class_init,
+    device_class, device_class_init,
     zeroable::Zeroable,
 };
 
@@ -57,7 +57,7 @@ fn test_device_decl_macros() {
         type Class = DummyClass;
         const TYPE_INFO: qemu_api::bindings::TypeInfo = qemu_api::type_info! { Self };
         const TYPE_NAME: &'static CStr = c_str!("dummy");
-        const PARENT_TYPE_NAME: Option<&'static CStr> = Some(TYPE_DEVICE);
+        const PARENT_TYPE_NAME: Option<&'static CStr> = Some(device_class::TYPE_DEVICE);
         const ABSTRACT: bool = false;
         const INSTANCE_INIT: Option<unsafe extern "C" fn(obj: *mut Object)> = None;
         const INSTANCE_POST_INIT: Option<unsafe extern "C" fn(obj: *mut Object)> = None;