From ccef9696f13b39b619f7b12d770a2908cc2ecdd3 Mon Sep 17 00:00:00 2001 From: "Jonathan A. Kollasch" Date: Wed, 29 Nov 2017 11:31:09 -0600 Subject: [PATCH] NetBSD: add sysctl backend for std::env::current_exe Use the CTL_KERN.KERN_PROC_ARGS.-1.KERN_PROC_PATHNAME sysctl in preference over the /proc/curproc/exe symlink. Additionally, perform more validation of aformentioned symlink. Particularly on pre-8.x NetBSD this symlink will point to '/' when accurate information is unavailable. --- src/libstd/sys/unix/os.rs | 29 ++++++++++++++++++++++++++++- 1 file changed, 28 insertions(+), 1 deletion(-) diff --git a/src/libstd/sys/unix/os.rs b/src/libstd/sys/unix/os.rs index 7e965b4b4c5b2..4f33a2b12fe5d 100644 --- a/src/libstd/sys/unix/os.rs +++ b/src/libstd/sys/unix/os.rs @@ -223,7 +223,34 @@ pub fn current_exe() -> io::Result { #[cfg(target_os = "netbsd")] pub fn current_exe() -> io::Result { - ::fs::read_link("/proc/curproc/exe") + fn sysctl() -> io::Result { + unsafe { + let mib = [libc::CTL_KERN, libc::KERN_PROC_ARGS, -1, libc::KERN_PROC_PATHNAME]; + let mut path_len: usize = 0; + cvt(libc::sysctl(mib.as_ptr(), mib.len() as ::libc::c_uint, + ptr::null_mut(), &mut path_len, + ptr::null(), 0))?; + if path_len <= 1 { + return Err(io::Error::new(io::ErrorKind::Other, + "KERN_PROC_PATHNAME sysctl returned zero-length string")) + } + let mut path: Vec = Vec::with_capacity(path_len); + cvt(libc::sysctl(mib.as_ptr(), mib.len() as ::libc::c_uint, + path.as_ptr() as *mut libc::c_void, &mut path_len, + ptr::null(), 0))?; + path.set_len(path_len - 1); // chop off NUL + Ok(PathBuf::from(OsString::from_vec(path))) + } + } + fn procfs() -> io::Result { + let curproc_exe = path::Path::new("/proc/curproc/exe"); + if curproc_exe.is_file() { + return ::fs::read_link(curproc_exe); + } + Err(io::Error::new(io::ErrorKind::Other, + "/proc/curproc/exe doesn't point to regular file.")) + } + sysctl().or_else(|_| procfs()) } #[cfg(any(target_os = "bitrig", target_os = "openbsd"))]