Add various pty functions

  * grantpt
  * ptsname/ptsname_r
  * posix_openpt
  * unlockpt

Author: Susurrus

src/lib.rs

@@ -44,6 +44,8 @@ pub mod mount;
 #[cfg(target_os = "linux")]
 pub mod mqueue;
 
+pub mod pty;
+
 #[cfg(any(target_os = "linux", target_os = "macos"))]
 pub mod poll;
 

src/pty.rs

@@ -0,0 +1,72 @@
+use std::ffi::CStr;
+use std::os::unix::io::RawFd;
+
+use libc;
+
+use {Errno, Error, fcntl, Result};
+
+pub fn grantpt(fd: RawFd) -> Result<()> {
+    if unsafe { libc::grantpt(fd) } < 0 {
+        return Err(Error::last().into());
+    }
+
+    Ok(())
+}
+
+pub fn posix_openpt(flags: fcntl::OFlag) -> Result<RawFd> {
+    let fd = unsafe {
+        libc::posix_openpt(flags.bits())
+    };
+
+    if fd < 0 {
+        return Err(Error::last().into());
+    }
+
+    Ok(fd)
+}
+
+pub fn ptsname(fd: RawFd) -> Result<String> {
+    let name_ptr = unsafe { libc::ptsname(fd) };
+    if name_ptr.is_null() {
+        return Err(Errno::ENOTTY.into());
+    }
+
+    let name_cstr = unsafe { CStr::from_ptr(name_ptr) };
+    let name = match name_cstr.to_str() {
+        Ok(s) => s.to_string(),
+        Err(_) => {
+            // FIXME: Unsure what error I should report here.
+            return Err(Error::last().into());
+        }
+    };
+    Ok(name)
+}
+
+#[cfg(any(target_os = "linux",
+          target_os = "android",
+          target_os = "emscripten",
+          target_os = "fuchsia"))]
+pub fn ptsname_r(fd: RawFd) -> Result<String> {
+    let mut name_buf = [0 as libc::c_char; 64];
+    if unsafe { libc::ptsname_r(fd, name_buf.as_mut_ptr(), name_buf.len()) } != 0 {
+        return Err(Error::last().into());
+    }
+
+    let name_cstr = unsafe { CStr::from_ptr(name_buf.as_ptr()) };
+    let name = match name_cstr.to_str() {
+        Ok(s) => s.to_string(),
+        Err(_) => {
+            // FIXME: Unsure what error I should report here.
+            return Err(Error::last().into());
+        }
+    };
+    Ok(name)
+}
+
+pub fn unlockpt(fd: RawFd) -> Result<()> {
+    if unsafe { libc::unlockpt(fd) } < 0 {
+        return Err(Error::last().into());
+    }
+
+    Ok(())
+}