Remove Program::fd() method

In recent times we started using file descriptor abstractions over "raw"
integers. As part of that we also relied on the AsFd trait and provided
implementations for the same.
Given that we implement this trait, it no longer makes sense to have a
dedicated fd() method. With this change we remove it from the Program
type.

Signed-off-by: Daniel Müller <[email protected]>

Author: d-e-s-o

examples/tc_port_whitelist/src/main.rs

@@ -1,6 +1,10 @@
+use std::os::unix::io::AsFd as _;
+
 use anyhow::bail;
 use anyhow::Result;
+
 use clap::Parser;
+
 use libbpf_rs::skel::OpenSkel;
 use libbpf_rs::skel::SkelBuilder;
 use libbpf_rs::MapFlags;
@@ -66,7 +70,7 @@ fn main() -> Result<()> {
     let progs = skel.progs();
     let ifidx = nix::net::if_::if_nametoindex(opts.iface.as_str())? as i32;
 
-    let mut tc_builder = TcHookBuilder::new(progs.handle_tc().fd());
+    let mut tc_builder = TcHookBuilder::new(progs.handle_tc().as_fd());
     tc_builder
         .ifindex(ifidx)
         .replace(true)
@@ -79,7 +83,7 @@ fn main() -> Result<()> {
     custom.parent(TC_H_CLSACT, TC_H_MIN_INGRESS).handle(2);
 
     // we can create a TcHook w/o the builder
-    let mut destroy_all = libbpf_rs::TcHook::new(progs.handle_tc().fd());
+    let mut destroy_all = libbpf_rs::TcHook::new(progs.handle_tc().as_fd());
     destroy_all
         .ifindex(ifidx)
         .attach_point(TC_EGRESS | TC_INGRESS);

examples/tproxy/src/main.rs

@@ -1,4 +1,5 @@
 use std::net::Ipv4Addr;
+use std::os::unix::io::AsFd as _;
 use std::str::FromStr;
 use std::sync::atomic::AtomicBool;
 use std::sync::atomic::Ordering;
@@ -71,7 +72,7 @@ fn main() -> Result<()> {
     let skel = open_skel.load()?;
     let progs = skel.progs();
     // Set up and attach ingress TC hook
-    let mut ingress = TcHookBuilder::new(progs.tproxy().fd())
+    let mut ingress = TcHookBuilder::new(progs.tproxy().as_fd())
         .ifindex(opts.ifindex)
         .replace(true)
         .handle(1)

libbpf-rs/CHANGELOG.md

@@ -13,6 +13,7 @@ Unreleased
 - Removed support for creating `Map` objects standalone (i.e. maps not created
   by libbpf)
 - Removed `Map::fd()` in favor of `Map::as_fd()`
+- Removed `Program::fd()` in favor of `Program::as_fd()`
 - Improved `btf_type_match!` macro, adding support for most of Rust's `match`
   capabilities
 - Added `skel` module exposing skeleton related traits

libbpf-rs/src/program.rs

@@ -416,11 +416,6 @@ impl Program {
         }
     }
 
-    /// Returns a file descriptor to the underlying program.
-    pub fn fd(&self) -> BorrowedFd {
-        self.as_fd()
-    }
-
     /// Returns program fd by id
     pub fn get_fd_by_id(id: u32) -> Result<OwnedFd> {
         let ret = unsafe { libbpf_sys::bpf_prog_get_fd_by_id(id) };
@@ -710,7 +705,12 @@ impl Program {
     /// Attach a verdict/parser to a [sockmap/sockhash](https://lwn.net/Articles/731133/)
     pub fn attach_sockmap(&self, map_fd: i32) -> Result<()> {
         let err = unsafe {
-            libbpf_sys::bpf_prog_attach(self.fd().as_raw_fd(), map_fd, self.attach_type() as u32, 0)
+            libbpf_sys::bpf_prog_attach(
+                self.as_fd().as_raw_fd(),
+                map_fd,
+                self.attach_type() as u32,
+                0,
+            )
         };
         util::parse_ret(err)
     }

libbpf-rs/tests/test.rs

@@ -1448,7 +1448,7 @@ fn test_sudo_program_get_fd_and_id() {
         .prog("handle__sched_wakeup")
         .expect("failed to find program");
 
-    let prog_fd = prog.fd();
+    let prog_fd = prog.as_fd();
     let prog_id = Program::get_id_by_fd(prog_fd).expect("failed to get program id by fd");
     let owned_prog_fd = Program::get_fd_by_id(prog_id).expect("failed to get program fd by id");
     close(owned_prog_fd.as_raw_fd()).expect("failed to close owned program fd");

libbpf-rs/tests/test_tc.rs

@@ -1,3 +1,4 @@
+use std::os::unix::io::AsFd as _;
 use std::os::unix::io::BorrowedFd;
 
 use serial_test::serial;
@@ -45,7 +46,7 @@ fn test_sudo_tc_basic_cycle() {
     bump_rlimit_mlock();
 
     let obj = get_test_object("tc-unit.bpf.o");
-    let fd = obj.prog("handle_tc").unwrap().fd();
+    let fd = obj.prog("handle_tc").unwrap().as_fd();
 
     let mut tc_builder = TcHookBuilder::new(fd);
     tc_builder
@@ -87,7 +88,7 @@ fn test_sudo_tc_attach_no_qdisc() {
     bump_rlimit_mlock();
 
     let obj = get_test_object("tc-unit.bpf.o");
-    let fd = obj.prog("handle_tc").unwrap().fd();
+    let fd = obj.prog("handle_tc").unwrap().as_fd();
 
     let mut tc_builder = TcHookBuilder::new(fd);
     tc_builder
@@ -112,7 +113,7 @@ fn test_sudo_tc_attach_basic() {
     bump_rlimit_mlock();
 
     let obj = get_test_object("tc-unit.bpf.o");
-    let fd = obj.prog("handle_tc").unwrap().fd();
+    let fd = obj.prog("handle_tc").unwrap().as_fd();
 
     let mut tc_builder = TcHookBuilder::new(fd);
     tc_builder
@@ -141,7 +142,7 @@ fn test_sudo_tc_attach_repeat() {
     bump_rlimit_mlock();
 
     let obj = get_test_object("tc-unit.bpf.o");
-    let fd = obj.prog("handle_tc").unwrap().fd();
+    let fd = obj.prog("handle_tc").unwrap().as_fd();
 
     let mut tc_builder = TcHookBuilder::new(fd);
     tc_builder
@@ -180,7 +181,7 @@ fn test_sudo_tc_attach_repeat() {
 fn test_sudo_tc_attach_custom() {
     bump_rlimit_mlock();
     let obj = get_test_object("tc-unit.bpf.o");
-    let fd = obj.prog("handle_tc").unwrap().fd();
+    let fd = obj.prog("handle_tc").unwrap().as_fd();
 
     let mut tc_builder = TcHookBuilder::new(fd);
     tc_builder
@@ -233,7 +234,7 @@ fn test_sudo_tc_attach_custom() {
 fn test_sudo_tc_detach_basic() {
     bump_rlimit_mlock();
     let obj = get_test_object("tc-unit.bpf.o");
-    let fd = obj.prog("handle_tc").unwrap().fd();
+    let fd = obj.prog("handle_tc").unwrap().as_fd();
 
     let mut tc_builder = TcHookBuilder::new(fd);
     tc_builder
@@ -280,7 +281,7 @@ fn test_sudo_tc_query() {
     bump_rlimit_mlock();
 
     let obj = get_test_object("tc-unit.bpf.o");
-    let fd = obj.prog("handle_tc").unwrap().fd();
+    let fd = obj.prog("handle_tc").unwrap().as_fd();
 
     let mut tc_builder = TcHookBuilder::new(fd);
     tc_builder
@@ -352,7 +353,7 @@ fn test_sudo_tc_double_create() {
     bump_rlimit_mlock();
 
     let obj = get_test_object("tc-unit.bpf.o");
-    let fd = obj.prog("handle_tc").unwrap().fd();
+    let fd = obj.prog("handle_tc").unwrap().as_fd();
 
     let mut tc_builder = TcHookBuilder::new(fd);
     tc_builder