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2019-02-28libstd => 2018Taiki Endo-1/+1
2018-12-25Remove licensesMark Rousskov-10/+0
2018-12-07Various minor/cosmetic improvements to codeAlexander Regueiro-1/+1
2018-10-23fix typos in various placesMatthias Krüger-1/+1
2018-10-05Address review commentsGabriel Majeri-43/+67
2018-09-28Rewrite section on concurrencyGabriel Majeri-4/+5
2018-09-28Fix broken linksGabriel Majeri-5/+7
2018-09-27Address review commentsGabriel Majeri-14/+15
Reword the lead paragraph and turn the list items into complete sentences.
2018-09-27Make example code use global variablesGabriel Majeri-13/+14
Because `fn main()` was added automatically, the variables were actually local statics.
2018-09-27Expand the documentation for the std::sync moduleGabriel Majeri-4/+119
Provides an overview on why synchronization is required, as well a short summary of what sync primitives are available.
2018-06-29Rename alloc::arc to alloc::sync, to match std::syncSimon Sapin-1/+1
2018-04-12Import the `alloc` crate as `alloc_crate` in stdSimon Sapin-1/+1
… to make the name `alloc` available.
2016-07-12std: Clean out deprecated APIsAlex Crichton-11/+3
This primarily removes a lot of `sync::Static*` APIs and rejiggers the associated implementations. While doing this it was discovered that the `is_poisoned` method can actually result in a data race for the Mutex/RwLock primitives, so the inner `Cell<bool>` was changed to an `AtomicBool` to prevent the associated data race. Otherwise the usage/gurantees should be the same they were before.
2016-05-24std: Stabilize APIs for the 1.10 releaseAlex Crichton-0/+4
This commit applies the FCP decisions made by the libs team for the 1.10 cycle, including both new stabilizations and deprecations. Specifically, the list of APIs is: Stabilized: * `os::windows::fs::OpenOptionsExt::access_mode` * `os::windows::fs::OpenOptionsExt::share_mode` * `os::windows::fs::OpenOptionsExt::custom_flags` * `os::windows::fs::OpenOptionsExt::attributes` * `os::windows::fs::OpenOptionsExt::security_qos_flags` * `os::unix::fs::OpenOptionsExt::custom_flags` * `sync::Weak::new` * `Default for sync::Weak` * `panic::set_hook` * `panic::take_hook` * `panic::PanicInfo` * `panic::PanicInfo::payload` * `panic::PanicInfo::location` * `panic::Location` * `panic::Location::file` * `panic::Location::line` * `ffi::CStr::from_bytes_with_nul` * `ffi::CStr::from_bytes_with_nul_unchecked` * `ffi::FromBytesWithNulError` * `fs::Metadata::modified` * `fs::Metadata::accessed` * `fs::Metadata::created` * `sync::atomic::Atomic{Usize,Isize,Bool,Ptr}::compare_exchange` * `sync::atomic::Atomic{Usize,Isize,Bool,Ptr}::compare_exchange_weak` * `collections::{btree,hash}_map::{Occupied,Vacant,}Entry::key` * `os::unix::net::{UnixStream, UnixListener, UnixDatagram, SocketAddr}` * `SocketAddr::is_unnamed` * `SocketAddr::as_pathname` * `UnixStream::connect` * `UnixStream::pair` * `UnixStream::try_clone` * `UnixStream::local_addr` * `UnixStream::peer_addr` * `UnixStream::set_read_timeout` * `UnixStream::set_write_timeout` * `UnixStream::read_timeout` * `UnixStream::write_Timeout` * `UnixStream::set_nonblocking` * `UnixStream::take_error` * `UnixStream::shutdown` * Read/Write/RawFd impls for `UnixStream` * `UnixListener::bind` * `UnixListener::accept` * `UnixListener::try_clone` * `UnixListener::local_addr` * `UnixListener::set_nonblocking` * `UnixListener::take_error` * `UnixListener::incoming` * RawFd impls for `UnixListener` * `UnixDatagram::bind` * `UnixDatagram::unbound` * `UnixDatagram::pair` * `UnixDatagram::connect` * `UnixDatagram::try_clone` * `UnixDatagram::local_addr` * `UnixDatagram::peer_addr` * `UnixDatagram::recv_from` * `UnixDatagram::recv` * `UnixDatagram::send_to` * `UnixDatagram::send` * `UnixDatagram::set_read_timeout` * `UnixDatagram::set_write_timeout` * `UnixDatagram::read_timeout` * `UnixDatagram::write_timeout` * `UnixDatagram::set_nonblocking` * `UnixDatagram::take_error` * `UnixDatagram::shutdown` * RawFd impls for `UnixDatagram` * `{BTree,Hash}Map::values_mut` * `<[_]>::binary_search_by_key` Deprecated: * `StaticCondvar` - this, and all other static synchronization primitives below, are usable today through the lazy-static crate on stable Rust today. Additionally, we'd like the non-static versions to be directly usable in a static context one day, so they're unlikely to be the final forms of the APIs in any case. * `CONDVAR_INIT` * `StaticMutex` * `MUTEX_INIT` * `StaticRwLock` * `RWLOCK_INIT` * `iter::Peekable::is_empty` Closes #27717 Closes #27720 cc #27784 (but encode methods still exist) Closes #30014 Closes #30425 Closes #30449 Closes #31190 Closes #31399 Closes #31767 Closes #32111 Closes #32281 Closes #32312 Closes #32551 Closes #33018
2016-05-11Export OnceState from libstdAmanieu d'Antras-1/+1
2016-03-12std: Clean out deprecated APIsAlex Crichton-4/+0
Removes all unstable and deprecated APIs prior to the 1.8 release. All APIs that are deprecated in the 1.8 release are sticking around for the rest of this cycle. Some notable changes are: * The `dynamic_lib` module was moved into `rustc_back` as the compiler still relies on a few bits and pieces. * The `DebugTuple` formatter now special-cases an empty struct name with only one field to append a trailing comma.
2016-03-04End stdlib module summaries with a full stop.Steve Klabnik-1/+1
Fixes #9447
2016-01-16std: Stabilize APIs for the 1.7 releaseAlex Crichton-0/+1
This commit stabilizes and deprecates the FCP (final comment period) APIs for the upcoming 1.7 beta release. The specific APIs which changed were: Stabilized * `Path::strip_prefix` (renamed from `relative_from`) * `path::StripPrefixError` (new error type returned from `strip_prefix`) * `Ipv4Addr::is_loopback` * `Ipv4Addr::is_private` * `Ipv4Addr::is_link_local` * `Ipv4Addr::is_multicast` * `Ipv4Addr::is_broadcast` * `Ipv4Addr::is_documentation` * `Ipv6Addr::is_unspecified` * `Ipv6Addr::is_loopback` * `Ipv6Addr::is_unique_local` * `Ipv6Addr::is_multicast` * `Vec::as_slice` * `Vec::as_mut_slice` * `String::as_str` * `String::as_mut_str` * `<[T]>::clone_from_slice` - the `usize` return value is removed * `<[T]>::sort_by_key` * `i32::checked_rem` (and other signed types) * `i32::checked_neg` (and other signed types) * `i32::checked_shl` (and other signed types) * `i32::checked_shr` (and other signed types) * `i32::saturating_mul` (and other signed types) * `i32::overflowing_add` (and other signed types) * `i32::overflowing_sub` (and other signed types) * `i32::overflowing_mul` (and other signed types) * `i32::overflowing_div` (and other signed types) * `i32::overflowing_rem` (and other signed types) * `i32::overflowing_neg` (and other signed types) * `i32::overflowing_shl` (and other signed types) * `i32::overflowing_shr` (and other signed types) * `u32::checked_rem` (and other unsigned types) * `u32::checked_neg` (and other unsigned types) * `u32::checked_shl` (and other unsigned types) * `u32::saturating_mul` (and other unsigned types) * `u32::overflowing_add` (and other unsigned types) * `u32::overflowing_sub` (and other unsigned types) * `u32::overflowing_mul` (and other unsigned types) * `u32::overflowing_div` (and other unsigned types) * `u32::overflowing_rem` (and other unsigned types) * `u32::overflowing_neg` (and other unsigned types) * `u32::overflowing_shl` (and other unsigned types) * `u32::overflowing_shr` (and other unsigned types) * `ffi::IntoStringError` * `CString::into_string` * `CString::into_bytes` * `CString::into_bytes_with_nul` * `From<CString> for Vec<u8>` * `From<CString> for Vec<u8>` * `IntoStringError::into_cstring` * `IntoStringError::utf8_error` * `Error for IntoStringError` Deprecated * `Path::relative_from` - renamed to `strip_prefix` * `Path::prefix` - use `components().next()` instead * `os::unix::fs` constants - moved to the `libc` crate * `fmt::{radix, Radix, RadixFmt}` - not used enough to stabilize * `IntoCow` - conflicts with `Into` and may come back later * `i32::{BITS, BYTES}` (and other integers) - not pulling their weight * `DebugTuple::formatter` - will be removed * `sync::Semaphore` - not used enough and confused with system semaphores Closes #23284 cc #27709 (still lots more methods though) Closes #27712 Closes #27722 Closes #27728 Closes #27735 Closes #27729 Closes #27755 Closes #27782 Closes #27798
2015-11-18Add missing annotations and some testsVadim Petrochenkov-0/+11
2015-08-22Auto merge of #27871 - alexcrichton:stabilize-libcore, r=aturonbors-1/+1
These commits move libcore into a state so that it's ready for stabilization, performing some minor cleanup: * The primitive modules for integers in the standard library were all removed from the source tree as they were just straight reexports of the libcore variants. * The `core::atomic` module now lives in `core::sync::atomic`. The `core::sync` module is otherwise empty, but ripe for expansion! * The `core::prelude::v1` module was stabilized after auditing that it is a subset of the standard library's prelude plus some primitive extension traits (char, str, and slice) * Some unstable-hacks for float parsing errors were shifted around to not use the same unstable hacks (e.g. the `flt2dec` module is now used for "privacy"). After this commit, the remaining large unstable functionality specific to libcore is: * `raw`, `intrinsics`, `nonzero`, `array`, `panicking`, `simd` -- these modules are all unstable or not reexported in the standard library, so they're just remaining in the same status quo as before * `num::Float` - this extension trait for floats needs to be audited for functionality (much of that is happening in #27823) and may also want to be renamed to `FloatExt` or `F32Ext`/`F64Ext`. * Should the extension traits for primitives be stabilized in libcore? I believe other unstable pieces are not isolated to just libcore but also affect the standard library. cc #27701
2015-08-19Turn TimedOut into a BarrierWaitResult style opaque typeSteven Fackler-1/+1
2015-08-19Make Condvar::wait_timeout return an enum instead of a boolSteven Fackler-1/+1
Returning a primitive bool results in a somewhat confusing API - does `true` indicate success - i.e. no timeout, or that a timeout has occurred? An explicitly named enum makes it clearer. [breaking-change]
2015-08-17core: Move `atomic` into a new `sync` moduleAlex Crichton-1/+1
This mirrors the same hierarchy in the standard library.
2015-08-12Remove all unstable deprecated functionalityAlex Crichton-4/+0
This commit removes all unstable and deprecated functions in the standard library. A release was recently cut (1.3) which makes this a good time for some spring cleaning of the deprecated functions.
2015-06-17More test fixes and fallout of stability changesAlex Crichton-0/+1
2015-04-08Implement reentrant mutexes and make stdio use themSimonas Kazlauskas-7/+6
write_fmt calls write for each formatted field. The default implementation of write_fmt is used, which will call write on not-yet-locked stdout (and write locking after), therefore making print! in multithreaded environment still interleave contents of two separate prints. This patch implements reentrant mutexes, changes stdio handles to use these mutexes and overrides write_fmt to lock the stdio handle for the whole duration of the call.
2015-03-31std: Clean out #[deprecated] APIsAlex Crichton-3/+0
This commit cleans out a large amount of deprecated APIs from the standard library and some of the facade crates as well, updating all users in the compiler and in tests as it goes along.
2015-02-25allow(deprecated) for TaskPool (fixup #22783)Manish Goregaokar-0/+1
2015-01-23grandfathered -> rust1Brian Anderson-1/+1
2015-01-21Add 'feature' and 'since' to stability attributesBrian Anderson-1/+1
2015-01-05rollup merge of #20565: alexcrichton/missing-stabilityAlex Crichton-1/+1
Conflicts: src/libstd/sync/mpsc/mod.rs
2015-01-05rollup merge of #20519: ville-h/rwlock-renameAlex Crichton-2/+2
Conflicts: src/libstd/sync/rwlock.rs
2015-01-04std: Fix missing stability in syncAlex Crichton-1/+1
* The `sync` module is stable * The `sync::mpsc` module is stable * The `Sender::send` method is stable. * The `Once::doit` method is now removed. * Deprecated atomic initializers are removed. * Renamed atomic initializers are now stable.
2015-01-04fix code referencing RwLockWriteGuardville-h-1/+1
2015-01-04fix code referencing RwLockReadGuardville-h-1/+1
2015-01-04fix code and comments referencing RW_LOCK_INITville-h-1/+1
2015-01-03Remove deprecated functionalityAlex Crichton-1/+1
This removes a large array of deprecated functionality, regardless of how recently it was deprecated. The purpose of this commit is to clean out the standard libraries and compiler for the upcoming alpha release. Some notable compiler changes were to enable warnings for all now-deprecated command line arguments (previously the deprecated versions were silently accepted) as well as removing deriving(Zero) entirely (the trait was removed). The distribution no longer contains the libtime or libregex_macros crates. Both of these have been deprecated for some time and are available externally.
2015-01-04fix code and comments referencing StaticRwLockville-h-1/+1
2015-01-04fix code and comments referencing RwLockville-h-1/+1
2015-01-02rollup merge of #20315: alexcrichton/std-syncAlex Crichton-1/+1
Conflicts: src/libstd/rt/exclusive.rs src/libstd/sync/barrier.rs src/libstd/sys/unix/pipe.rs src/test/bench/shootout-binarytrees.rs src/test/bench/shootout-fannkuch-redux.rs
2015-01-02rollup merge of #20273: alexcrichton/second-pass-commAlex Crichton-0/+2
Conflicts: src/doc/guide.md src/libcollections/bit.rs src/libcollections/btree/node.rs src/libcollections/slice.rs src/libcore/ops.rs src/libcore/prelude.rs src/librand/rand_impls.rs src/librustc/middle/check_match.rs src/librustc/middle/infer/region_inference/mod.rs src/librustc_driver/lib.rs src/librustdoc/test.rs src/libstd/bitflags.rs src/libstd/io/comm_adapters.rs src/libstd/io/mem.rs src/libstd/io/mod.rs src/libstd/io/net/pipe.rs src/libstd/io/net/tcp.rs src/libstd/io/net/udp.rs src/libstd/io/pipe.rs src/libstd/io/process.rs src/libstd/io/stdio.rs src/libstd/io/timer.rs src/libstd/io/util.rs src/libstd/macros.rs src/libstd/os.rs src/libstd/path/posix.rs src/libstd/path/windows.rs src/libstd/prelude/v1.rs src/libstd/rand/mod.rs src/libstd/rand/os.rs src/libstd/sync/barrier.rs src/libstd/sync/condvar.rs src/libstd/sync/future.rs src/libstd/sync/mpsc/mod.rs src/libstd/sync/mpsc/mpsc_queue.rs src/libstd/sync/mpsc/select.rs src/libstd/sync/mpsc/spsc_queue.rs src/libstd/sync/mutex.rs src/libstd/sync/once.rs src/libstd/sync/rwlock.rs src/libstd/sync/semaphore.rs src/libstd/sync/task_pool.rs src/libstd/sys/common/helper_thread.rs src/libstd/sys/unix/process.rs src/libstd/sys/unix/timer.rs src/libstd/sys/windows/c.rs src/libstd/sys/windows/timer.rs src/libstd/sys/windows/tty.rs src/libstd/thread.rs src/libstd/thread_local/mod.rs src/libstd/thread_local/scoped.rs src/libtest/lib.rs src/test/auxiliary/cci_capture_clause.rs src/test/bench/shootout-reverse-complement.rs src/test/bench/shootout-spectralnorm.rs src/test/compile-fail/array-old-syntax-2.rs src/test/compile-fail/bind-by-move-no-guards.rs src/test/compile-fail/builtin-superkinds-self-type.rs src/test/compile-fail/comm-not-freeze-receiver.rs src/test/compile-fail/comm-not-freeze.rs src/test/compile-fail/issue-12041.rs src/test/compile-fail/unsendable-class.rs src/test/run-pass/builtin-superkinds-capabilities-transitive.rs src/test/run-pass/builtin-superkinds-capabilities-xc.rs src/test/run-pass/builtin-superkinds-capabilities.rs src/test/run-pass/builtin-superkinds-self-type.rs src/test/run-pass/capturing-logging.rs src/test/run-pass/closure-bounds-can-capture-chan.rs src/test/run-pass/comm.rs src/test/run-pass/core-run-destroy.rs src/test/run-pass/drop-trait-enum.rs src/test/run-pass/hashmap-memory.rs src/test/run-pass/issue-13494.rs src/test/run-pass/issue-3609.rs src/test/run-pass/issue-4446.rs src/test/run-pass/issue-4448.rs src/test/run-pass/issue-8827.rs src/test/run-pass/issue-9396.rs src/test/run-pass/ivec-tag.rs src/test/run-pass/rust-log-filter.rs src/test/run-pass/send-resource.rs src/test/run-pass/send-type-inference.rs src/test/run-pass/sendable-class.rs src/test/run-pass/spawn-types.rs src/test/run-pass/task-comm-0.rs src/test/run-pass/task-comm-10.rs src/test/run-pass/task-comm-11.rs src/test/run-pass/task-comm-13.rs src/test/run-pass/task-comm-14.rs src/test/run-pass/task-comm-15.rs src/test/run-pass/task-comm-16.rs src/test/run-pass/task-comm-3.rs src/test/run-pass/task-comm-4.rs src/test/run-pass/task-comm-5.rs src/test/run-pass/task-comm-6.rs src/test/run-pass/task-comm-7.rs src/test/run-pass/task-comm-9.rs src/test/run-pass/task-comm-chan-nil.rs src/test/run-pass/task-spawn-move-and-copy.rs src/test/run-pass/task-stderr.rs src/test/run-pass/tcp-accept-stress.rs src/test/run-pass/tcp-connect-timeouts.rs src/test/run-pass/tempfile.rs src/test/run-pass/trait-bounds-in-arc.rs src/test/run-pass/trivial-message.rs src/test/run-pass/unique-send-2.rs src/test/run-pass/unique-send.rs src/test/run-pass/unwind-resource.rs
2015-01-01std: Second pass stabilization of syncAlex Crichton-1/+1
This pass performs a second pass of stabilization through the `std::sync` module, avoiding modules/types that are being handled in other PRs (e.g. mutexes, rwlocks, condvars, and channels). The following items are now stable * `sync::atomic` * `sync::atomic::ATOMIC_BOOL_INIT` (was `INIT_ATOMIC_BOOL`) * `sync::atomic::ATOMIC_INT_INIT` (was `INIT_ATOMIC_INT`) * `sync::atomic::ATOMIC_UINT_INIT` (was `INIT_ATOMIC_UINT`) * `sync::Once` * `sync::ONCE_INIT` * `sync::Once::call_once` (was `doit`) * C == `pthread_once(..)` * Boost == `call_once(..)` * Windows == `InitOnceExecuteOnce` * `sync::Barrier` * `sync::Barrier::new` * `sync::Barrier::wait` (now returns a `bool`) * `sync::Semaphore::new` * `sync::Semaphore::acquire` * `sync::Semaphore::release` The following items remain unstable * `sync::SemaphoreGuard` * `sync::Semaphore::access` - it's unclear how this relates to the poisoning story of mutexes. * `sync::TaskPool` - the semantics of a failing task and whether a thread is re-attached to a thread pool are somewhat unclear, and the utility of this type in `sync` is question with respect to the jobs of other primitives. This type will likely become stable or move out of the standard library over time. * `sync::Future` - futures as-is have yet to be deeply re-evaluated with the recent core changes to Rust's synchronization story, and will likely become stable in the future but are unstable until that time comes. [breaking-change]
2014-12-29std: Stabilization pass for mutex/rwlock/condvarAlex Crichton-12/+2
This commit performs a stabilization pass over the sync::{mutex, rwlock, condvar} modules, marking the following items as stable: * Mutex * Mutex::new * Mutex::lock * Mutex::try_lock * MutexGuard * RWLock * RWLock::new * RWLock::read * RWLock::try_read * RWLock::write * RWLock::try_write * RWLockReadGuard * RWLockWriteGuard * Condvar * Condvar::new * Condvar::wait * Condvar::notify_one * Condvar::notify_all * PoisonError * TryLockError * TryLockError::Poisoned * TryLockError::WouldBlock * LockResult * TryLockResult The following items remain unstable to explore future possibilities of unifying the static/non-static variants of the types: * StaticMutex * StaticMutex::new * StaticMutex::lock * StaticMutex::try_lock * StaticMutex::desroy * StaticRWLock * StaticRWLock::new * StaticRWLock::read * StaticRWLock::try_read * StaticRWLock::write * StaticRWLock::try_write * StaticRWLock::destroy The following items were removed in favor of `Guard<'static, ()>` instead. * StaticMutexGuard * StaticRWLockReadGuard * StaticRWLockWriteGuard
2014-12-29std: Second pass stabilization for `comm`Alex Crichton-0/+2
This commit is a second pass stabilization for the `std::comm` module, performing the following actions: * The entire `std::comm` module was moved under `std::sync::mpsc`. This movement reflects that channels are just yet another synchronization primitive, and they don't necessarily deserve a special place outside of the other concurrency primitives that the standard library offers. * The `send` and `recv` methods have all been removed. * The `send_opt` and `recv_opt` methods have been renamed to `send` and `recv`. This means that all send/receive operations return a `Result` now indicating whether the operation was successful or not. * The error type of `send` is now a `SendError` to implement a custom error message and allow for `unwrap()`. The error type contains an `into_inner` method to extract the value. * The error type of `recv` is now `RecvError` for the same reasons as `send`. * The `TryRecvError` and `TrySendError` types have had public reexports removed of their variants and the variant names have been tweaked with enum namespacing rules. * The `Messages` iterator is renamed to `Iter` This functionality is now all `#[stable]`: * `Sender` * `SyncSender` * `Receiver` * `std::sync::mpsc` * `channel` * `sync_channel` * `Iter` * `Sender::send` * `Sender::clone` * `SyncSender::send` * `SyncSender::try_send` * `SyncSender::clone` * `Receiver::recv` * `Receiver::try_recv` * `Receiver::iter` * `SendError` * `RecvError` * `TrySendError::{mod, Full, Disconnected}` * `TryRecvError::{mod, Empty, Disconnected}` * `SendError::into_inner` * `TrySendError::into_inner` This is a breaking change due to the modification of where this module is located, as well as the changing of the semantics of `send` and `recv`. Most programs just need to rename imports of `std::comm` to `std::sync::mpsc` and add calls to `unwrap` after a send or a receive operation. [breaking-change]
2014-12-29std: Return Result from RWLock/Mutex methodsAlex Crichton-2/+13
All of the current std::sync primitives have poisoning enable which means that when a task fails inside of a write-access lock then all future attempts to acquire the lock will fail. This strategy ensures that stale data whose invariants are possibly not upheld are never viewed by other tasks to help propagate unexpected panics (bugs in a program) among tasks. Currently there is no way to test whether a mutex or rwlock is poisoned. One method would be to duplicate all the methods with a sister foo_catch function, for example. This pattern is, however, against our [error guidelines][errors]. As a result, this commit exposes the fact that a task has failed internally through the return value of a `Result`. [errors]: https://github.com/rust-lang/rfcs/blob/master/text/0236-error-conventions.md#do-not-provide-both-result-and-fail-variants All methods now return a `LockResult<T>` or a `TryLockResult<T>` which communicates whether the lock was poisoned or not. In a `LockResult`, both the `Ok` and `Err` variants contains the `MutexGuard<T>` that is being returned in order to allow access to the data if poisoning is not desired. This also means that the lock is *always* held upon returning from `.lock()`. A new type, `PoisonError`, was added with one method `into_guard` which can consume the assertion that a lock is poisoned to gain access to the underlying data. This is a breaking change because the signatures of these methods have changed, often incompatible ways. One major difference is that the `wait` methods on a condition variable now consume the guard and return it in as a `LockResult` to indicate whether the lock was poisoned while waiting. Most code can be updated by calling `.unwrap()` on the return value of `.lock()`. [breaking-change]
2014-12-05std: Rewrite the `sync` moduleAlex Crichton-29/+15
This commit is a reimplementation of `std::sync` to be based on the system-provided primitives wherever possible. The previous implementation was fundamentally built on top of channels, and as part of the runtime reform it has become clear that this is not the level of abstraction that the standard level should be providing. This rewrite aims to provide as thin of a shim as possible on top of the system primitives in order to make them safe. The overall interface of the `std::sync` module has in general not changed, but there are a few important distinctions, highlighted below: * The condition variable type, `Condvar`, has been separated out of a `Mutex`. A condition variable is now an entirely separate type. This separation benefits users who only use one mutex, and provides a clearer distinction of who's responsible for managing condition variables (the application). * All of `Condvar`, `Mutex`, and `RWLock` are now directly built on top of system primitives rather than using a custom implementation. The `Once`, `Barrier`, and `Semaphore` types are still built upon these abstractions of the system primitives. * The `Condvar`, `Mutex`, and `RWLock` types all have a new static type and constant initializer corresponding to them. These are provided primarily for C FFI interoperation, but are often useful to otherwise simply have a global lock. The types, however, will leak memory unless `destroy()` is called on them, which is clearly documented. * The `Condvar` implementation for an `RWLock` write lock has been removed. This may be added back in the future with a userspace implementation, but this commit is focused on exposing the system primitives first. * The fundamental architecture of this design is to provide two separate layers. The first layer is that exposed by `sys_common` which is a cross-platform bare-metal abstraction of the system synchronization primitives. No attempt is made at making this layer safe, and it is quite unsafe to use! It is currently not exported as part of the API of the standard library, but the stabilization of the `sys` module will ensure that these will be exposed in time. The purpose of this layer is to provide the core cross-platform abstractions if necessary to implementors. The second layer is the layer provided by `std::sync` which is intended to be the thinnest possible layer on top of `sys_common` which is entirely safe to use. There are a few concerns which need to be addressed when making these system primitives safe: * Once used, the OS primitives can never be **moved**. This means that they essentially need to have a stable address. The static primitives use `&'static self` to enforce this, and the non-static primitives all use a `Box` to provide this guarantee. * Poisoning is leveraged to ensure that invalid data is not accessible from other tasks after one has panicked. In addition to these overall blanket safety limitations, each primitive has a few restrictions of its own: * Mutexes and rwlocks can only be unlocked from the same thread that they were locked by. This is achieved through RAII lock guards which cannot be sent across threads. * Mutexes and rwlocks can only be unlocked if they were previously locked. This is achieved by not exposing an unlocking method. * A condition variable can only be waited on with a locked mutex. This is achieved by requiring a `MutexGuard` in the `wait()` method. * A condition variable cannot be used concurrently with more than one mutex. This is guaranteed by dynamically binding a condition variable to precisely one mutex for its entire lifecycle. This restriction may be able to be relaxed in the future (a mutex is unbound when no threads are waiting on the condvar), but for now it is sufficient to guarantee safety. * Condvars now support timeouts for their blocking operations. The implementation for these operations is provided by the system. Due to the modification of the `Condvar` API, removal of the `std::sync::mutex` API, and reimplementation, this is a breaking change. Most code should be fairly easy to port using the examples in the documentation of these primitives. [breaking-change] Closes #17094 Closes #18003
2014-11-24Merge libsync into libstdAaron Turon-7/+31
This patch merges the `libsync` crate into `libstd`, undoing part of the facade. This is in preparation for ultimately merging `librustrt`, as well as the upcoming rewrite of `sync`. Because this removes the `libsync` crate, it is a: [breaking-change] However, all uses of `libsync` should be able to reroute through `std::sync` and `std::comm` instead.
2014-10-19Remove a large amount of deprecated functionalityAlex Crichton-3/+0
Spring cleaning is here! In the Fall! This commit removes quite a large amount of deprecated functionality from the standard libraries. I tried to ensure that only old deprecated functionality was removed. This is removing lots and lots of deprecated features, so this is a breaking change. Please consult the deprecation messages of the deleted code to see how to migrate code forward if it still needs migration. [breaking-change]
2014-08-18libsyntax: Remove the `use foo = bar` syntax from the language in favorPatrick Walton-1/+1
of `use bar as foo`. Change all uses of `use foo = bar` to `use bar as foo`. Implements RFC #47. Closes #16461. [breaking-change]
2014-08-07Fix typomdinger-1/+1