Added ptrace support for BSDs

* Moved ptrace API into it's own module with cfg'ed modules exported for linux/android or BSDs.
* Replicated current linux API for BSD
* Added API functions to peek and poke memory to avoid needing to replicate deprecated linux API and remaining feature complete
* Added helper function for `PTRACE_KILL` requests
* Updated tests based on new API changes
* Added addition kill calls to `test_ptrace_cont` as inferior death doesn't happen immediately on OSX which caused issues in the tests.

2 files changed, 29 insertions, 6 deletions

diff --git a/test/sys/mod.rs b/test/sys/mod.rs
index bdc079d8..46f29123 100644
--- a/test/sys/mod.rs
+++ b/test/sys/mod.rs
@@ -27,5 +27,10 @@ mod test_uio;
 mod test_epoll;
 mod test_pthread;
 #[cfg(any(target_os = "android",
-          target_os = "linux"))]
+          target_os = "dragonfly",
+          target_os = "freebsd",
+          target_os = "linux",
+          target_os = "macos",
+          target_os = "netbsd",
+          target_os = "openbsd"))]
 mod test_ptrace;
diff --git a/test/sys/test_ptrace.rs b/test/sys/test_ptrace.rs
index a15a7921..24d9b522 100644
--- a/test/sys/test_ptrace.rs
+++ b/test/sys/test_ptrace.rs
@@ -1,7 +1,9 @@
 use nix::Error;
 use nix::errno::Errno;
 use nix::unistd::getpid;
-use nix::sys::ptrace::{self, Options};
+use nix::sys::ptrace;
+#[cfg(any(target_os = "android", target_os = "linux"))]
+use nix::sys::ptrace::Options;
 
 #[cfg(any(target_os = "android", target_os = "linux"))]
 use std::mem;
@@ -11,11 +13,13 @@ fn test_ptrace() {
     // Just make sure ptrace can be called at all, for now.
     // FIXME: qemu-user doesn't implement ptrace on all arches, so permit ENOSYS
     let err = ptrace::attach(getpid()).unwrap_err();
-    assert!(err == Error::Sys(Errno::EPERM) || err == Error::Sys(Errno::ENOSYS));
+    assert!(err == Error::Sys(Errno::EPERM) || err == Error::Sys(Errno::EINVAL) ||
+            err == Error::Sys(Errno::ENOSYS));
 }
 
 // Just make sure ptrace_setoptions can be called at all, for now.
 #[test]
+#[cfg(any(target_os = "android", target_os = "linux"))]
 fn test_ptrace_setoptions() {
     let err = ptrace::setoptions(getpid(), Options::PTRACE_O_TRACESYSGOOD).unwrap_err();
     assert!(err != Error::UnsupportedOperation);
@@ -23,6 +27,7 @@ fn test_ptrace_setoptions() {
 
 // Just make sure ptrace_getevent can be called at all, for now.
 #[test]
+#[cfg(any(target_os = "android", target_os = "linux"))]
 fn test_ptrace_getevent() {
     let err = ptrace::getevent(getpid()).unwrap_err();
     assert!(err != Error::UnsupportedOperation);
@@ -30,6 +35,7 @@ fn test_ptrace_getevent() {
 
 // Just make sure ptrace_getsiginfo can be called at all, for now.
 #[test]
+#[cfg(any(target_os = "android", target_os = "linux"))]
 fn test_ptrace_getsiginfo() {
     if let Err(Error::UnsupportedOperation) = ptrace::getsiginfo(getpid()) {
         panic!("ptrace_getsiginfo returns Error::UnsupportedOperation!");
@@ -38,6 +44,7 @@ fn test_ptrace_getsiginfo() {
 
 // Just make sure ptrace_setsiginfo can be called at all, for now.
 #[test]
+#[cfg(any(target_os = "android", target_os = "linux"))]
 fn test_ptrace_setsiginfo() {
     let siginfo = unsafe { mem::uninitialized() };
     if let Err(Error::UnsupportedOperation) = ptrace::setsiginfo(getpid(), &siginfo) {
@@ -50,10 +57,12 @@ fn test_ptrace_setsiginfo() {
 fn test_ptrace_cont() {
     use nix::sys::ptrace;
     use nix::sys::signal::{raise, Signal};
-    use nix::sys::wait::{waitpid, WaitStatus};
+    use nix::sys::wait::{waitpid, WaitPidFlag, WaitStatus};
     use nix::unistd::fork;
     use nix::unistd::ForkResult::*;
 
+    let _m = ::FORK_MTX.lock().expect("Mutex got poisoned by another test");
+
     // FIXME: qemu-user doesn't implement ptrace on all architectures
     // and retunrs ENOSYS in this case.
     // We (ab)use this behavior to detect the affected platforms
@@ -79,9 +88,18 @@ fn test_ptrace_cont() {
             assert_eq!(waitpid(child, None), Ok(WaitStatus::Stopped(child, Signal::SIGTRAP)));
             ptrace::cont(child, None).unwrap();
             assert_eq!(waitpid(child, None), Ok(WaitStatus::Stopped(child, Signal::SIGTRAP)));
-            ptrace::cont(child, Signal::SIGKILL).unwrap();
+            ptrace::cont(child, Some(Signal::SIGKILL)).unwrap();
             match waitpid(child, None) {
-                Ok(WaitStatus::Signaled(pid, Signal::SIGKILL, _)) if pid == child => {}
+                Ok(WaitStatus::Signaled(pid, Signal::SIGKILL, _)) if pid == child => {
+                    // FIXME It's been observed on some systems (apple) the 
+                    // tracee may not be killed but remain as a zombie process
+                    // affecting other wait based tests. Add an extra kill just
+                    // to make sure there are no zombies.
+                    let _ = waitpid(child, Some(WaitPidFlag::WNOHANG));
+                    while ptrace::cont(child, Some(Signal::SIGKILL)).is_ok() {
+                        let _ = waitpid(child, Some(WaitPidFlag::WNOHANG));
+                    }
+                }
                 _ => panic!("The process should have been killed"),
             }
         },