Add getrlimit(2) and setrlimit(2)

Author: kamalmarhubi

src/sys/mod.rs

@@ -15,6 +15,8 @@ pub mod memfd;
 #[cfg(not(any(target_os = "ios", target_os = "freebsd", target_os = "dragonfly")))]
 pub mod ioctl;
 
+pub mod resource;
+
 #[cfg(any(target_os = "linux", target_os = "android"))]
 pub mod sendfile;
 

src/sys/resource.rs

@@ -0,0 +1,54 @@
+use std::mem;
+
+use libc::{self, c_int};
+pub use libc::{rlimit, RLIM_INFINITY};
+#[cfg(any(target_os = "linux",
+          target_os = "openbsd",
+          target_os = "netbsd",
+          target_os = "bitrig"))]
+pub use libc::{RLIM_SAVED_CUR, RLIM_SAVED_MAX};
+
+use {Errno, Result};
+
+#[repr(i32)]
+pub enum Resource {
+    // POSIX
+    RLIMIT_CORE = libc::RLIMIT_CORE,
+    RLIMIT_CPU = libc::RLIMIT_CPU,
+    RLIMIT_DATA = libc::RLIMIT_DATA,
+    RLIMIT_FSIZE = libc::RLIMIT_FSIZE,
+    RLIMIT_NOFILE = libc::RLIMIT_NOFILE,
+    RLIMIT_STACK = libc::RLIMIT_STACK,
+    RLIMIT_AS = libc::RLIMIT_AS,
+    // BSDs and Linux
+    #[cfg(all(unix, not(target_os = "solaris")))]
+    RLIMIT_MEMLOCK = libc::RLIMIT_MEMLOCK,
+    #[cfg(all(unix, not(target_os = "solaris")))]
+    RLIMIT_NPROC = libc::RLIMIT_NPROC,
+    #[cfg(all(unix, not(target_os = "solaris")))]
+    RLIMIT_RSS = libc::RLIMIT_RSS,
+    // Linux-only
+    #[cfg(any(target_os = "linux", target_os = "android"))]
+    RLIMIT_LOCKS = libc::RLIMIT_LOCKS,
+    #[cfg(any(target_os = "linux", target_os = "android"))]
+    RLIMIT_MSGQUEUE = libc::RLIMIT_MSGQUEUE,
+    #[cfg(any(target_os = "linux", target_os = "android"))]
+    RLIMIT_NICE = libc::RLIMIT_NICE,
+    #[cfg(any(target_os = "linux", target_os = "android"))]
+    RLIMIT_RTPRIO = libc::RLIMIT_RTPRIO,
+    #[cfg(any(target_os = "linux", target_os = "android"))]
+    RLIMIT_RTTIME = libc::RLIMIT_RTTIME,
+    #[cfg(any(target_os = "linux", target_os = "android"))]
+    RLIMIT_SIGPENDING = libc::RLIMIT_SIGPENDING,
+}
+
+pub fn getrlimit(resource: Resource) -> Result<rlimit> {
+    let mut rlim = unsafe { mem::uninitialized() };
+    let res = unsafe { libc::getrlimit(resource as c_int, &mut rlim as *mut _) };
+    Errno::result(res).map(|_| rlim)
+}
+
+pub fn setrlimit(resource: Resource, rlim: rlimit) -> Result<()> {
+    let res = unsafe { libc::setrlimit(resource as c_int, &rlim as *const _) };
+    Errno::result(res).map(drop)
+}

test/test.rs

@@ -11,6 +11,7 @@ mod sys;
 mod test_fcntl;
 mod test_net;
 mod test_nix_path;
+mod test_resource;
 #[cfg(any(target_os = "linux", target_os = "android"))]
 mod test_sendfile;
 mod test_stat;

test/test_resource.rs

@@ -0,0 +1,22 @@
+use nix::sys::resource::{Resource, getrlimit, setrlimit};
+
+#[test]
+pub fn test_resource_limits() {
+    let mut limit = getrlimit(Resource::RLIMIT_STACK).unwrap();
+    assert!(limit.rlim_cur != limit.rlim_max);
+
+    let orig_limit = limit;
+
+    limit.rlim_cur = limit.rlim_max;
+    setrlimit(Resource::RLIMIT_STACK, limit).unwrap();
+
+    let limit2 = getrlimit(Resource::RLIMIT_STACK).unwrap();
+    assert_eq!(limit.rlim_cur, limit2.rlim_cur);
+    assert_eq!(limit.rlim_max, limit2.rlim_max);
+
+    setrlimit(Resource::RLIMIT_STACK, orig_limit).unwrap();
+
+    let final_limit = getrlimit(Resource::RLIMIT_STACK).unwrap();
+    assert_eq!(orig_limit.rlim_cur, final_limit.rlim_cur);
+    assert_eq!(orig_limit.rlim_max, final_limit.rlim_max);
+}