libfdt: Add adb_subnode_with_name_len() and subnode_with_name_len()
APIs are added to create a node and its supernodes without allocating
tokenized names.
Bug: 277993056
Test: atest liblibfdt.integration_test
Change-Id: I5a43d41e0bea1e9b7d0182b98d9aa5e0c079dd2e
diff --git a/libs/libfdt/src/lib.rs b/libs/libfdt/src/lib.rs
index 5683ce3..d800c13 100644
--- a/libs/libfdt/src/lib.rs
+++ b/libs/libfdt/src/lib.rs
@@ -670,12 +670,49 @@
/// Adds a new subnode to the given node and return it as a FdtNodeMut on success.
pub fn add_subnode(&'a mut self, name: &CStr) -> Result<Self> {
+ let offset = self.add_subnode_offset(name.to_bytes())?;
+ Ok(Self { fdt: self.fdt, offset })
+ }
+
+ /// Adds a new subnode to the given node with name and namelen, and returns it as a FdtNodeMut
+ /// on success.
+ pub fn add_subnode_with_namelen(&'a mut self, name: &CStr, namelen: usize) -> Result<Self> {
+ let offset = { self.add_subnode_offset(&name.to_bytes()[..namelen])? };
+ Ok(Self { fdt: self.fdt, offset })
+ }
+
+ fn add_subnode_offset(&mut self, name: &[u8]) -> Result<c_int> {
+ let namelen = name.len().try_into().unwrap();
// SAFETY: Accesses are constrained to the DT totalsize (validated by ctor).
let ret = unsafe {
- libfdt_bindgen::fdt_add_subnode(self.fdt.as_mut_ptr(), self.offset, name.as_ptr())
+ libfdt_bindgen::fdt_add_subnode_namelen(
+ self.fdt.as_mut_ptr(),
+ self.offset,
+ name.as_ptr().cast::<_>(),
+ namelen,
+ )
};
+ fdt_err(ret)
+ }
- Ok(Self { fdt: self.fdt, offset: fdt_err(ret)? })
+ /// Returns the subnode of the given name with len.
+ pub fn subnode_with_namelen(&'a mut self, name: &CStr, namelen: usize) -> Result<Option<Self>> {
+ let offset = self.subnode_offset(&name.to_bytes()[..namelen])?;
+ Ok(offset.map(|offset| Self { fdt: self.fdt, offset }))
+ }
+
+ fn subnode_offset(&self, name: &[u8]) -> Result<Option<c_int>> {
+ let namelen = name.len().try_into().unwrap();
+ // SAFETY: Accesses are constrained to the DT totalsize (validated by ctor).
+ let ret = unsafe {
+ libfdt_bindgen::fdt_subnode_offset_namelen(
+ self.fdt.as_ptr(),
+ self.offset,
+ name.as_ptr().cast::<_>(),
+ namelen,
+ )
+ };
+ fdt_err_or_option(ret)
}
fn parent(&'a self) -> Result<FdtNode<'a>> {