[libc-commits] [libc] [llvm] [libc][CndVar] reimplmement conditional variable with FIFO ordering (PR #192748)

[Michael Jones via libc-commits]

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@@ -6,49 +6,406 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC___SUPPORT_SRC_THREADS_LINUX_CNDVAR_H
-#define LLVM_LIBC___SUPPORT_SRC_THREADS_LINUX_CNDVAR_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_THREADS_CNDVAR_H
+#define LLVM_LIBC_SRC___SUPPORT_THREADS_CNDVAR_H
 
 #include "hdr/stdint_proxy.h" // uint32_t
+#include "src/__support/CPP/mutex.h"
+#include "src/__support/CPP/new.h"
 #include "src/__support/macros/config.h"
-#include "src/__support/threads/futex_utils.h"       // Futex
-#include "src/__support/threads/mutex.h"             // Mutex
-#include "src/__support/threads/raw_mutex.h"         // RawMutex
+#include "src/__support/threads/futex_utils.h" // Futex
+#include "src/__support/threads/mutex.h"       // Mutex
+#include "src/__support/threads/raw_mutex.h"   // RawMutex
+
+#ifndef LIBC_COPT_TIMEOUT_ENSURE_MONOTONICITY
+#define LIBC_COPT_TIMEOUT_ENSURE_MONOTONICITY 1
+#endif
 
 namespace LIBC_NAMESPACE_DECL {
 
-class CndVar {
-  enum CndWaiterStatus : uint32_t {
-    WS_Waiting = 0xE,
-    WS_Signalled = 0x5,
+enum class CndVarResult {
+  // The waiter successfully received a signal.
+  Success,
+  // Error occurs during mutex acquisition.
+  MutexError,
+  // Timeout occurs.
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michaelrj-google wrote:

these comments are unnecessary. Remove.

https://github.com/llvm/llvm-project/pull/192748