rts/OSThreads: Improve error handling consistency

Previously we relied on the caller to check the return value from
broadcastCondition and friends, most of whom neglected to do so. Given
that these functions should not fail anyways, I've opted to drop the
return value entirely and rather move the result check into the
OSThreads functions.

This slightly changes the semantics of timedWaitCondition which now
returns false only in the case of timeout, rather than any error as
previously done.

3 files changed, 33 insertions, 23 deletions

diff --git a/includes/rts/OSThreads.h b/includes/rts/OSThreads.h
index b711036b17..08d90de06e 100644
--- a/includes/rts/OSThreads.h
+++ b/includes/rts/OSThreads.h
@@ -173,9 +173,10 @@ extern void joinOSThread          ( OSThreadId id );
 //
 extern void initCondition         ( Condition* pCond );
 extern void closeCondition        ( Condition* pCond );
-extern bool broadcastCondition    ( Condition* pCond );
-extern bool signalCondition       ( Condition* pCond );
-extern bool waitCondition         ( Condition* pCond, Mutex* pMut );
+extern void broadcastCondition    ( Condition* pCond );
+extern void signalCondition       ( Condition* pCond );
+extern void waitCondition         ( Condition* pCond, Mutex* pMut );
+// Returns false on timeout, true otherwise.
 extern bool timedWaitCondition    ( Condition* pCond, Mutex* pMut, Time timeout);
 
 //
diff --git a/rts/posix/OSThreads.c b/rts/posix/OSThreads.c
index 8ac23d4168..04375006d2 100644
--- a/rts/posix/OSThreads.c
+++ b/rts/posix/OSThreads.c
@@ -104,33 +104,31 @@
 void
 initCondition( Condition* pCond )
 {
-  pthread_cond_init(pCond, NULL);
-  return;
+  CHECK(pthread_cond_init(pCond, NULL) == 0);
 }
 
 void
 closeCondition( Condition* pCond )
 {
-  pthread_cond_destroy(pCond);
-  return;
+  CHECK(pthread_cond_destroy(pCond) == 0);
 }
 
-bool
+void
 broadcastCondition ( Condition* pCond )
 {
-  return (pthread_cond_broadcast(pCond) == 0);
+  CHECK(pthread_cond_broadcast(pCond) == 0);
 }
 
-bool
+void
 signalCondition ( Condition* pCond )
 {
-  return (pthread_cond_signal(pCond) == 0);
+  CHECK(pthread_cond_signal(pCond) == 0);
 }
 
-bool
+void
 waitCondition ( Condition* pCond, Mutex* pMut )
 {
-  return (pthread_cond_wait(pCond,pMut) == 0);
+  CHECK(pthread_cond_wait(pCond,pMut) == 0);
 }
 
 bool
@@ -143,7 +141,15 @@ timedWaitCondition ( Condition* pCond, Mutex* pMut, Time timeout) {
         .tv_nsec = TimeToNS(timeout - SecondsToTime(secs))
     };
 
-    return pthread_cond_timedwait(pCond,pMut, &t) == 0;
+    int ret = pthread_cond_timedwait(pCond,pMut, &t);
+    switch (ret) {
+    case ETIMEDOUT:
+        return false;
+    case 0:
+        return true;
+    default:
+        barf("pthread_cond_timedwait failed");
+    }
 }
 
 void
diff --git a/rts/win32/OSThreads.c b/rts/win32/OSThreads.c
index 46e363b3ab..2c1e462cb4 100644
--- a/rts/win32/OSThreads.c
+++ b/rts/win32/OSThreads.c
@@ -543,25 +543,22 @@ closeCondition( Condition* pCond STG_UNUSED)
   return;
 }
 
-bool
+void
 broadcastCondition ( Condition* pCond )
 {
   WakeAllConditionVariable(pCond);
-  return true;
 }
 
-bool
+void
 signalCondition ( Condition* pCond )
 {
   WakeConditionVariable(pCond);
-  return true;
 }
 
-bool
+void
 waitCondition ( Condition* pCond, Mutex* pMut )
 {
-  SleepConditionVariableSRW(pCond, pMut, INFINITE, 0);
-  return true;
+  CHECK(SleepConditionVariableSRW(pCond, pMut, INFINITE, 0));
 }
 
 bool
@@ -570,8 +567,14 @@ timedWaitCondition ( Condition* pCond, Mutex* pMut, Time timeout )
   // If we pass a timeout of 0 SleepConditionVariableSRW will return immediately
   // https://docs.microsoft.com/en-us/windows/win32/api/synchapi/nf-synchapi-sleepconditionvariablesrw
   DWORD ms = (DWORD)stg_min(1, TimeToMS(timeout));
-  SleepConditionVariableSRW(pCond, pMut, ms, 0);
-  return true;
+  BOOL res = SleepConditionVariableSRW(pCond, pMut, ms, 0);
+  if (res) {
+    return true; // success
+  } else if (GetLastError() == ERROR_TIMEOUT) {
+    return false; // timeout
+  } else {
+    barf("timedWaitCondition: error %" FMT_Word, (StgWord) GetLastError());
+  }
 }
 
 void