[PATCH 2/3] rust_binder: store Option<Error> in TransactionInfo

[Alice Ryhl]

Store Option<Error> instead of a raw i32 errno in TransactionInfo so
that the Error value can be used directly when formatting transaction
failures without having to reconstruct it from the integer errno.

Signed-off-by: Alice Ryhl <aliceryhl@xxxxxxxxxx>
---
 drivers/android/binder/thread.rs      | 6 +++---
 drivers/android/binder/transaction.rs | 8 ++++++--
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/drivers/android/binder/thread.rs b/drivers/android/binder/thread.rs
index e5ae3b0e56c5..5bb7ae2f7920 100644
--- a/drivers/android/binder/thread.rs
+++ b/drivers/android/binder/thread.rs
@@ -1333,8 +1333,8 @@ fn transaction(self: &Arc<Self>, cmd: u32, reader: &mut UserSliceReader) -> Resu
             if err.reply != BR_TRANSACTION_COMPLETE {
                 info.reply = err.reply;
                 info.error_line = Some(err.line);
-                if let Some(source) = &err.source {
-                    info.errno = source.to_errno();
+                if let Some(source) = err.source {
+                    info.errno = Some(source);
 
                     {
                         let mut inner = self.inner.lock();
@@ -1476,7 +1476,7 @@ fn reply_inner(self: &Arc<Self>, info: &mut TransactionInfo) -> BinderResult {
             orig.from
                 .deliver_reply(Err(BR_FAILED_REPLY), &orig, Some(ee));
             info.reply = BR_FAILED_REPLY;
-            info.errno = param;
+            info.errno = err.source;
             info.error_line = Some(err.line);
             err.reply = BR_TRANSACTION_COMPLETE;
             err
diff --git a/drivers/android/binder/transaction.rs b/drivers/android/binder/transaction.rs
index e627522141b8..d934c6821b15 100644
--- a/drivers/android/binder/transaction.rs
+++ b/drivers/android/binder/transaction.rs
@@ -136,7 +136,11 @@ fn new(info: &TransactionInfo, ctx: &crate::Context) -> Self {
             offsets_size: info.offsets_size,
             return_error_line: if failed { info.error_line } else { None },
             return_error: if failed { info.reply } else { 0 },
-            return_error_param: if failed { info.errno } else { 0 },
+            return_error_param: if failed {
+                info.errno.map_or(0, |e| e.to_errno())
+            } else {
+                0
+            },
             context_name,
         }
     }
@@ -254,7 +258,7 @@ pub(crate) struct TransactionInfo {
     pub(crate) offsets_size: usize,
     pub(crate) buffers_size: usize,
     pub(crate) target_handle: u32,
-    pub(crate) errno: i32,
+    pub(crate) errno: Option<Error>,
     pub(crate) reply: u32,
     pub(crate) error_line: Option<ErrorLocation>,
     pub(crate) oneway_spam_suspect: bool,

-- 
2.56.0.rc1.315.gc6ed9934b7-goog