[avb] Move PartitionName and util methods to separate modules
This is a refactoring. There's no behavior change in this cl.
Bug: 256148034
Test: m pvmfw_img && atest libpvmfw_avb.integration_test
Change-Id: I3926076293cead03db0ca3409fc82fc120cb80ce
diff --git a/pvmfw/avb/src/utils.rs b/pvmfw/avb/src/utils.rs
new file mode 100644
index 0000000..bb27497
--- /dev/null
+++ b/pvmfw/avb/src/utils.rs
@@ -0,0 +1,53 @@
+// Copyright 2023, The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//! Common utility functions.
+
+use crate::error::AvbIOError;
+use core::ptr::NonNull;
+
+pub(crate) fn write<T>(ptr: *mut T, value: T) -> Result<(), AvbIOError> {
+ let ptr = to_nonnull(ptr)?;
+ // SAFETY: It is safe as the raw pointer `ptr` is a nonnull pointer.
+ unsafe {
+ *ptr.as_ptr() = value;
+ }
+ Ok(())
+}
+
+pub(crate) fn as_ref<'a, T>(ptr: *mut T) -> Result<&'a T, AvbIOError> {
+ let ptr = to_nonnull(ptr)?;
+ // SAFETY: It is safe as the raw pointer `ptr` is a nonnull pointer.
+ unsafe { Ok(ptr.as_ref()) }
+}
+
+pub(crate) fn to_nonnull<T>(ptr: *mut T) -> Result<NonNull<T>, AvbIOError> {
+ NonNull::new(ptr).ok_or(AvbIOError::NoSuchValue)
+}
+
+pub(crate) fn is_not_null<T>(ptr: *const T) -> Result<(), AvbIOError> {
+ if ptr.is_null() {
+ Err(AvbIOError::NoSuchValue)
+ } else {
+ Ok(())
+ }
+}
+
+pub(crate) fn to_usize<T: TryInto<usize>>(num: T) -> Result<usize, AvbIOError> {
+ num.try_into().map_err(|_| AvbIOError::InvalidValueSize)
+}
+
+pub(crate) fn usize_checked_add(x: usize, y: usize) -> Result<usize, AvbIOError> {
+ x.checked_add(y).ok_or(AvbIOError::InvalidValueSize)
+}