From 9de89e037af45b046017aa9caebeced63b4a464b Mon Sep 17 00:00:00 2001
From: Paul Sajna <paulsajna@gmail.com>
Date: Sun, 4 Mar 2018 09:03:46 -0800
Subject: [PATCH] fchdir

---
 platform/src/linux/mod.rs | 6 ++++++
 platform/src/redox/mod.rs | 5 +++++
 src/unistd/src/lib.rs     | 2 +-
 3 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/platform/src/linux/mod.rs b/platform/src/linux/mod.rs
index 20c1d59355..e810f8d483 100644
--- a/platform/src/linux/mod.rs
+++ b/platform/src/linux/mod.rs
@@ -51,6 +51,12 @@ pub fn fchown(fildes: c_int, owner: uid_t, group: gid_t) -> c_int {
     }
 }
 
+pub fn fchdir(fildes: c_int) -> c_int {
+    unsafe {
+        syscall!(FCHDIR, fildes) as c_int
+    }
+}
+
 #[cfg(target_arch = "x86_64")]
 pub fn open(path: *const c_char, oflag: c_int, mode: mode_t) -> c_int {
     unsafe {
diff --git a/platform/src/redox/mod.rs b/platform/src/redox/mod.rs
index 02755a3c9e..f80e5fd3de 100644
--- a/platform/src/redox/mod.rs
+++ b/platform/src/redox/mod.rs
@@ -40,6 +40,11 @@ pub fn fchown(fd: c_int, owner: uid_t, group: gid_t) -> c_int {
     syscall::fchown(owner, group)? as c_int
 }
 
+pub fn fchdir(fd: c_int) -> c_int {
+    let path = fpath(fd as usize, &[]).unwrap();
+    syscall::chdir(path)? as c_int
+}
+
 pub fn open(path: *const c_char, oflag: c_int, mode: mode_t) -> c_int {
     let path = unsafe { c_str(path) };
     syscall::open(path, (oflag as usize) | (mode as usize)).unwrap() as c_int
diff --git a/src/unistd/src/lib.rs b/src/unistd/src/lib.rs
index 2b7de078b4..d60f11bcee 100644
--- a/src/unistd/src/lib.rs
+++ b/src/unistd/src/lib.rs
@@ -136,7 +136,7 @@ pub extern "C" fn fchown(fildes: c_int, owner: uid_t, group: gid_t) -> c_int {
 
 #[no_mangle]
 pub extern "C" fn fchdir(fildes: c_int) -> c_int {
-    unimplemented!();
+    platform::fchdir(fildes)
 }
 
 #[no_mangle]