Rollup merge of #139343 - cberner:filelock_wouldblock, r=workingjubilee

Change signature of File::try_lock and File::try_lock_shared

These methods now return Result<(), TryLockError> instead of Result<bool, Error> to make their use less errorprone

These methods are unstable under the "file_lock" feature. The related tracking issue is https://github.com/rust-lang/rust/pull/130999 and this PR changes the signatures as discussed by libs-api: https://github.com/rust-lang/rust/issues/130994#issuecomment-2770838848

7 files changed, 58 insertions, 41 deletions

diff --git a/library/std/src/sys/fs/hermit.rs b/library/std/src/sys/fs/hermit.rs
index 99690abe8ed..a9774bef9e3 100644
--- a/library/std/src/sys/fs/hermit.rs
+++ b/library/std/src/sys/fs/hermit.rs
@@ -1,4 +1,5 @@
 use crate::ffi::{CStr, OsStr, OsString, c_char};
+use crate::fs::TryLockError;
 use crate::io::{self, BorrowedCursor, Error, ErrorKind, IoSlice, IoSliceMut, SeekFrom};
 use crate::os::hermit::ffi::OsStringExt;
 use crate::os::hermit::hermit_abi::{
@@ -12,7 +13,7 @@ use crate::sys::common::small_c_string::run_path_with_cstr;
 use crate::sys::fd::FileDesc;
 pub use crate::sys::fs::common::{copy, exists};
 use crate::sys::time::SystemTime;
-use crate::sys::{cvt, unsupported};
+use crate::sys::{cvt, unsupported, unsupported_err};
 use crate::sys_common::{AsInner, AsInnerMut, FromInner, IntoInner};
 use crate::{fmt, mem};
 
@@ -366,12 +367,12 @@ impl File {
         unsupported()
     }
 
-    pub fn try_lock(&self) -> io::Result<bool> {
-        unsupported()
+    pub fn try_lock(&self) -> Result<(), TryLockError> {
+        Err(TryLockError::Error(unsupported_err()))
     }
 
-    pub fn try_lock_shared(&self) -> io::Result<bool> {
-        unsupported()
+    pub fn try_lock_shared(&self) -> Result<(), TryLockError> {
+        Err(TryLockError::Error(unsupported_err()))
     }
 
     pub fn unlock(&self) -> io::Result<()> {
diff --git a/library/std/src/sys/fs/solid.rs b/library/std/src/sys/fs/solid.rs
index 39de933b724..3bfb39bac95 100644
--- a/library/std/src/sys/fs/solid.rs
+++ b/library/std/src/sys/fs/solid.rs
@@ -2,6 +2,7 @@
 
 use crate::ffi::{CStr, CString, OsStr, OsString};
 use crate::fmt;
+use crate::fs::TryLockError;
 use crate::io::{self, BorrowedCursor, IoSlice, IoSliceMut, SeekFrom};
 use crate::mem::MaybeUninit;
 use crate::os::raw::{c_int, c_short};
@@ -11,7 +12,7 @@ use crate::sync::Arc;
 pub use crate::sys::fs::common::exists;
 use crate::sys::pal::{abi, error};
 use crate::sys::time::SystemTime;
-use crate::sys::unsupported;
+use crate::sys::{unsupported, unsupported_err};
 use crate::sys_common::ignore_notfound;
 
 type CIntNotMinusOne = core::num::niche_types::NotAllOnes<c_int>;
@@ -352,12 +353,12 @@ impl File {
         unsupported()
     }
 
-    pub fn try_lock(&self) -> io::Result<bool> {
-        unsupported()
+    pub fn try_lock(&self) -> Result<(), TryLockError> {
+        Err(TryLockError::Error(unsupported_err()))
     }
 
-    pub fn try_lock_shared(&self) -> io::Result<bool> {
-        unsupported()
+    pub fn try_lock_shared(&self) -> Result<(), TryLockError> {
+        Err(TryLockError::Error(unsupported_err()))
     }
 
     pub fn unlock(&self) -> io::Result<()> {
diff --git a/library/std/src/sys/fs/uefi.rs b/library/std/src/sys/fs/uefi.rs
index d6ae86bd3d2..416c90b98b6 100644
--- a/library/std/src/sys/fs/uefi.rs
+++ b/library/std/src/sys/fs/uefi.rs
@@ -2,6 +2,7 @@ use r_efi::protocols::file;
 
 use crate::ffi::OsString;
 use crate::fmt;
+use crate::fs::TryLockError;
 use crate::hash::Hash;
 use crate::io::{self, BorrowedCursor, IoSlice, IoSliceMut, SeekFrom};
 use crate::path::{Path, PathBuf};
@@ -227,11 +228,11 @@ impl File {
         self.0
     }
 
-    pub fn try_lock(&self) -> io::Result<bool> {
+    pub fn try_lock(&self) -> Result<(), TryLockError> {
         self.0
     }
 
-    pub fn try_lock_shared(&self) -> io::Result<bool> {
+    pub fn try_lock_shared(&self) -> Result<(), TryLockError> {
         self.0
     }
 
diff --git a/library/std/src/sys/fs/unix.rs b/library/std/src/sys/fs/unix.rs
index 5af59a2a914..863358596c1 100644
--- a/library/std/src/sys/fs/unix.rs
+++ b/library/std/src/sys/fs/unix.rs
@@ -75,6 +75,7 @@ use libc::{dirent64, fstat64, ftruncate64, lseek64, lstat64, off64_t, open64, st
 
 use crate::ffi::{CStr, OsStr, OsString};
 use crate::fmt::{self, Write as _};
+use crate::fs::TryLockError;
 use crate::io::{self, BorrowedCursor, Error, IoSlice, IoSliceMut, SeekFrom};
 use crate::os::unix::io::{AsFd, AsRawFd, BorrowedFd, FromRawFd, IntoRawFd};
 use crate::os::unix::prelude::*;
@@ -1310,15 +1311,17 @@ impl File {
         target_os = "netbsd",
         target_vendor = "apple",
     ))]
-    pub fn try_lock(&self) -> io::Result<bool> {
+    pub fn try_lock(&self) -> Result<(), TryLockError> {
         let result = cvt(unsafe { libc::flock(self.as_raw_fd(), libc::LOCK_EX | libc::LOCK_NB) });
-        if let Err(ref err) = result {
+        if let Err(err) = result {
             if err.kind() == io::ErrorKind::WouldBlock {
-                return Ok(false);
+                Err(TryLockError::WouldBlock)
+            } else {
+                Err(TryLockError::Error(err))
             }
+        } else {
+            Ok(())
         }
-        result?;
-        return Ok(true);
     }
 
     #[cfg(not(any(
@@ -1328,8 +1331,11 @@ impl File {
         target_os = "netbsd",
         target_vendor = "apple",
     )))]
-    pub fn try_lock(&self) -> io::Result<bool> {
-        Err(io::const_error!(io::ErrorKind::Unsupported, "try_lock() not supported"))
+    pub fn try_lock(&self) -> Result<(), TryLockError> {
+        Err(TryLockError::Error(io::const_error!(
+            io::ErrorKind::Unsupported,
+            "try_lock() not supported"
+        )))
     }
 
     #[cfg(any(
@@ -1339,15 +1345,17 @@ impl File {
         target_os = "netbsd",
         target_vendor = "apple",
     ))]
-    pub fn try_lock_shared(&self) -> io::Result<bool> {
+    pub fn try_lock_shared(&self) -> Result<(), TryLockError> {
         let result = cvt(unsafe { libc::flock(self.as_raw_fd(), libc::LOCK_SH | libc::LOCK_NB) });
-        if let Err(ref err) = result {
+        if let Err(err) = result {
             if err.kind() == io::ErrorKind::WouldBlock {
-                return Ok(false);
+                Err(TryLockError::WouldBlock)
+            } else {
+                Err(TryLockError::Error(err))
             }
+        } else {
+            Ok(())
         }
-        result?;
-        return Ok(true);
     }
 
     #[cfg(not(any(
@@ -1357,8 +1365,11 @@ impl File {
         target_os = "netbsd",
         target_vendor = "apple",
     )))]
-    pub fn try_lock_shared(&self) -> io::Result<bool> {
-        Err(io::const_error!(io::ErrorKind::Unsupported, "try_lock_shared() not supported"))
+    pub fn try_lock_shared(&self) -> Result<(), TryLockError> {
+        Err(TryLockError::Error(io::const_error!(
+            io::ErrorKind::Unsupported,
+            "try_lock_shared() not supported"
+        )))
     }
 
     #[cfg(any(
diff --git a/library/std/src/sys/fs/unsupported.rs b/library/std/src/sys/fs/unsupported.rs
index 45e93deffa3..0ff9533c047 100644
--- a/library/std/src/sys/fs/unsupported.rs
+++ b/library/std/src/sys/fs/unsupported.rs
@@ -1,5 +1,6 @@
 use crate::ffi::OsString;
 use crate::fmt;
+use crate::fs::TryLockError;
 use crate::hash::{Hash, Hasher};
 use crate::io::{self, BorrowedCursor, IoSlice, IoSliceMut, SeekFrom};
 use crate::path::{Path, PathBuf};
@@ -206,11 +207,11 @@ impl File {
         self.0
     }
 
-    pub fn try_lock(&self) -> io::Result<bool> {
+    pub fn try_lock(&self) -> Result<(), TryLockError> {
         self.0
     }
 
-    pub fn try_lock_shared(&self) -> io::Result<bool> {
+    pub fn try_lock_shared(&self) -> Result<(), TryLockError> {
         self.0
     }
 
diff --git a/library/std/src/sys/fs/wasi.rs b/library/std/src/sys/fs/wasi.rs
index 773040571bc..ebfc7377a2e 100644
--- a/library/std/src/sys/fs/wasi.rs
+++ b/library/std/src/sys/fs/wasi.rs
@@ -1,4 +1,5 @@
 use crate::ffi::{CStr, OsStr, OsString};
+use crate::fs::TryLockError;
 use crate::io::{self, BorrowedCursor, IoSlice, IoSliceMut, SeekFrom};
 use crate::mem::{self, ManuallyDrop};
 use crate::os::raw::c_int;
@@ -10,7 +11,7 @@ use crate::sys::common::small_c_string::run_path_with_cstr;
 use crate::sys::fd::WasiFd;
 pub use crate::sys::fs::common::exists;
 use crate::sys::time::SystemTime;
-use crate::sys::unsupported;
+use crate::sys::{unsupported, unsupported_err};
 use crate::sys_common::{AsInner, FromInner, IntoInner, ignore_notfound};
 use crate::{fmt, iter, ptr};
 
@@ -461,12 +462,12 @@ impl File {
         unsupported()
     }
 
-    pub fn try_lock(&self) -> io::Result<bool> {
-        unsupported()
+    pub fn try_lock(&self) -> Result<(), TryLockError> {
+        Err(TryLockError::Error(unsupported_err()))
     }
 
-    pub fn try_lock_shared(&self) -> io::Result<bool> {
-        unsupported()
+    pub fn try_lock_shared(&self) -> Result<(), TryLockError> {
+        Err(TryLockError::Error(unsupported_err()))
     }
 
     pub fn unlock(&self) -> io::Result<()> {
diff --git a/library/std/src/sys/fs/windows.rs b/library/std/src/sys/fs/windows.rs
index 9215f937567..9039fd00f5d 100644
--- a/library/std/src/sys/fs/windows.rs
+++ b/library/std/src/sys/fs/windows.rs
@@ -3,6 +3,7 @@
 use crate::alloc::{Layout, alloc, dealloc};
 use crate::borrow::Cow;
 use crate::ffi::{OsStr, OsString, c_void};
+use crate::fs::TryLockError;
 use crate::io::{self, BorrowedCursor, Error, IoSlice, IoSliceMut, SeekFrom};
 use crate::mem::{self, MaybeUninit, offset_of};
 use crate::os::windows::io::{AsHandle, BorrowedHandle};
@@ -399,7 +400,7 @@ impl File {
         self.acquire_lock(0)
     }
 
-    pub fn try_lock(&self) -> io::Result<bool> {
+    pub fn try_lock(&self) -> Result<(), TryLockError> {
         let result = cvt(unsafe {
             let mut overlapped = mem::zeroed();
             c::LockFileEx(
@@ -413,18 +414,18 @@ impl File {
         });
 
         match result {
-            Ok(_) => Ok(true),
+            Ok(_) => Ok(()),
             Err(err)
                 if err.raw_os_error() == Some(c::ERROR_IO_PENDING as i32)
                     || err.raw_os_error() == Some(c::ERROR_LOCK_VIOLATION as i32) =>
             {
-                Ok(false)
+                Err(TryLockError::WouldBlock)
             }
-            Err(err) => Err(err),
+            Err(err) => Err(TryLockError::Error(err)),
         }
     }
 
-    pub fn try_lock_shared(&self) -> io::Result<bool> {
+    pub fn try_lock_shared(&self) -> Result<(), TryLockError> {
         let result = cvt(unsafe {
             let mut overlapped = mem::zeroed();
             c::LockFileEx(
@@ -438,14 +439,14 @@ impl File {
         });
 
         match result {
-            Ok(_) => Ok(true),
+            Ok(_) => Ok(()),
             Err(err)
                 if err.raw_os_error() == Some(c::ERROR_IO_PENDING as i32)
                     || err.raw_os_error() == Some(c::ERROR_LOCK_VIOLATION as i32) =>
             {
-                Ok(false)
+                Err(TryLockError::WouldBlock)
             }
-            Err(err) => Err(err),
+            Err(err) => Err(TryLockError::Error(err)),
         }
     }