From f095ac2685627d72de7c93420b9584faaf06b8d3 Mon Sep 17 00:00:00 2001
From: reigadegr <2722688642@qq.com>
Date: Wed, 23 Sep 2026 08:00:03 +0800
Subject: [PATCH] fix(fs): Enable `sendfile` on Android

The `sendfile` function, its module declaration, and its re-export
were gated on `target_os = "linux"`, which excludes Android. Since
Android uses the Linux kernel and its bionic libc provides
`sendfile64`, these should be gated on `linux_kernel` instead.

This is consistent with the rest of the codebase (e.g. `copy_file_range`,
`raw_dir`, `statx`, `ioctl` all use `linux_kernel`) and with
`sendfile.rs` itself, which already uses `#[cfg(linux_kernel)]` on the
public function. The mismatch meant the module was never compiled on
Android despite the function being correctly gated.
---
 src/backend/libc/fs/syscalls.rs | 2 +-
 src/fs/mod.rs                   | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/backend/libc/fs/syscalls.rs b/src/backend/libc/fs/syscalls.rs
index c95eaf561..07000f3dc 100644
--- a/src/backend/libc/fs/syscalls.rs
+++ b/src/backend/libc/fs/syscalls.rs
@@ -1908,7 +1908,7 @@ const SYS_OPENAT2: i32 = 437;
 #[cfg(all(linux_kernel, target_pointer_width = "64"))]
 const SYS_OPENAT2: i64 = 437;
 
-#[cfg(target_os = "linux")]
+#[cfg(linux_kernel)]
 pub(crate) fn sendfile(
     out_fd: BorrowedFd<'_>,
     in_fd: BorrowedFd<'_>,
diff --git a/src/fs/mod.rs b/src/fs/mod.rs
index dfeed87ad..baf9d7e14 100644
--- a/src/fs/mod.rs
+++ b/src/fs/mod.rs
@@ -51,7 +51,7 @@ mod openat2;
 #[cfg(linux_kernel)]
 mod raw_dir;
 mod seek_from;
-#[cfg(target_os = "linux")]
+#[cfg(linux_kernel)]
 mod sendfile;
 #[cfg(not(target_os = "espidf"))]
 mod special;
@@ -117,7 +117,7 @@ pub use openat2::openat2;
 #[cfg(linux_kernel)]
 pub use raw_dir::{RawDir, RawDirEntry};
 pub use seek_from::SeekFrom;
-#[cfg(target_os = "linux")]
+#[cfg(linux_kernel)]
 pub use sendfile::sendfile;
 #[cfg(not(target_os = "espidf"))]
 pub use special::*;