Merge branch 'patch5' into 'master'

feat: rwlock

Closes #196

See merge request redox-os/relibc!594

src/platform/redox/clone.rs

@@ -7,29 +7,6 @@ use syscall::{
     SetSighandlerData, SIGCONT,
 };
 
-use crate::sync::rwlock::Rwlock;
-
 use redox_rt::{proc::FdGuard, signal::sighandler_function};
 
-pub use redox_rt::proc::*;
-
-static CLONE_LOCK: Rwlock = Rwlock::new(crate::pthread::Pshared::Private);
-
-struct Guard;
-impl Drop for Guard {
-    fn drop(&mut self) {
-        CLONE_LOCK.unlock()
-    }
-}
-
-pub fn rdlock() -> impl Drop {
-    CLONE_LOCK.acquire_read_lock(None);
-
-    Guard
-}
-pub fn wrlock() -> impl Drop {
-    CLONE_LOCK.acquire_write_lock(None);
-
-    Guard
-}
-pub use redox_rt::thread::*;
+pub use redox_rt::{proc::*, thread::*};

src/platform/redox/mod.rs

@@ -34,6 +34,7 @@ use crate::{
         unistd::{F_OK, R_OK, W_OK, X_OK},
     },
     io::{self, prelude::*, BufReader},
+    sync::rwlock::RwLock,
 };
 
 pub use redox_rt::proc::FdGuard;
@@ -75,6 +76,8 @@ macro_rules! path_from_c_str {
 
 use self::{exec::Executable, path::canonicalize};
 
+static CLONE_LOCK: RwLock<()> = RwLock::new(());
+
 /// Redox syscall implementation of the platform abstraction layer.
 pub struct Sys;
 
@@ -260,7 +263,7 @@ impl Pal for Sys {
 
     unsafe fn fork() -> Result<pid_t> {
         // TODO: Find way to avoid lock.
-        let _guard = clone::wrlock();
+        let _guard = CLONE_LOCK.write();
 
         Ok(clone::fork_impl()? as pid_t)
     }
@@ -726,7 +729,7 @@ impl Pal for Sys {
     }
 
     unsafe fn rlct_clone(stack: *mut usize) -> Result<crate::pthread::OsTid> {
-        let _guard = clone::rdlock();
+        let _guard = CLONE_LOCK.read();
         let res = clone::rlct_clone_impl(stack);
 
         res.map(|mut fd| crate::pthread::OsTid {