From 8437d676fba8219229baa26dff19658c958fe5df Mon Sep 17 00:00:00 2001
From: Darryl Pogue <dvpdiner2@gmail.com>
Date: Sun, 4 Mar 2012 14:18:44 -0800
Subject: [PATCH] Support named semaphores on *nix.

---
 Sources/Plasma/CoreLib/hsThread.h        | 11 +++-----
 Sources/Plasma/CoreLib/hsThread_Unix.cpp | 36 ++++++++++++++++++------
 2 files changed, 32 insertions(+), 15 deletions(-)

diff --git a/Sources/Plasma/CoreLib/hsThread.h b/Sources/Plasma/CoreLib/hsThread.h
index 8e162c3d..dc8418b7 100644
--- a/Sources/Plasma/CoreLib/hsThread.h
+++ b/Sources/Plasma/CoreLib/hsThread.h
@@ -145,7 +145,8 @@ class hsSemaphore {
     HANDLE  fSemaH;
 #elif HS_BUILD_FOR_UNIX
 #ifdef USE_SEMA
-    sem_t   fPSema;
+    sem_t*  fPSema;
+    bool    fNamed;
 #else
     pthread_mutex_t fPMutex;
     pthread_cond_t  fPCond;
@@ -153,13 +154,9 @@ class hsSemaphore {
 #endif
 #endif
 public:
-#ifdef HS_BUILD_FOR_WIN32
-    hsSemaphore(int initialValue=0, const char *name=nil);
-#else
-    hsSemaphore(int initialValue=0);
-#endif
+    hsSemaphore(int initialValue=0, const char* name=nil);
     ~hsSemaphore();
-    
+
     hsBool      Wait(hsMilliseconds timeToWait = kPosInfinity32);
     void        Signal();
 };
diff --git a/Sources/Plasma/CoreLib/hsThread_Unix.cpp b/Sources/Plasma/CoreLib/hsThread_Unix.cpp
index 8a25586b..109492a3 100644
--- a/Sources/Plasma/CoreLib/hsThread_Unix.cpp
+++ b/Sources/Plasma/CoreLib/hsThread_Unix.cpp
@@ -42,6 +42,8 @@ You can contact Cyan Worlds, Inc. by email legal@cyan.com
 #include "hsThread.h"
 #include "hsExceptions.h"
 #include <sys/errno.h>
+#include <sys/stat.h>
+#include <fcntl.h>
 #include <string.h>
 
 #define NO_POSIX_CLOCK 1
@@ -72,7 +74,7 @@ extern "C" {
     static void* gEntryPoint(void* param)
     {
         pthread_mutex_lock(((hsThread*)param)->GetStartupMutex());
-        void* ret = (void*)((hsThread*)param)->Run();
+        void* ret = (void*)(uintptr_t)((hsThread*)param)->Run();
         pthread_mutex_unlock(((hsThread*)param)->GetStartupMutex());
         pthread_exit(ret);
         return ret;
@@ -266,12 +268,24 @@ void hsMutex::Unlock()
 
 /////////////////////////////////////////////////////////////////////////////
 
-hsSemaphore::hsSemaphore(int initialValue)
+hsSemaphore::hsSemaphore(int initialValue, const char* name)
 {
 #ifdef USE_SEMA
-    int shared = 0; // 1 if sharing between processes
-    int status = ::sem_init(&fPSema, shared, initialValue);
-    hsThrowIfOSErr(status);
+    fPSema = nil;
+    if ((fNamed = (name != nil))) {
+        /* Named semaphore shared between processes */
+        fPSema = sem_open(name, O_CREAT, 0666, initialValue);
+        if (fPSema == SEM_FAILED)
+        {
+            hsAssert(0, "hsOSException");
+            throw hsOSException(errno);
+        }
+    } else {
+        /* Anonymous semaphore shared between threads */
+        int shared = 0; // 1 if sharing between processes
+        int status = sem_init(fPSema, shared, initialValue);
+        hsThrowIfOSErr(status);
+    }
 #else
     int status = ::pthread_mutex_init(&fPMutex, nil);
     hsThrowIfOSErr(status);
@@ -286,7 +300,12 @@ hsSemaphore::hsSemaphore(int initialValue)
 hsSemaphore::~hsSemaphore()
 {
 #ifdef USE_SEMA
-    int status = ::sem_destroy(&fPSema);
+    int status = 0;
+    if (fNamed) {
+        status = sem_close(fPSema);
+    } else {
+        status = sem_destroy(fPSema);
+    }
     hsThrowIfOSErr(status);
 #else
     int status = ::pthread_cond_destroy(&fPCond);
@@ -300,8 +319,9 @@ hsSemaphore::~hsSemaphore()
 hsBool hsSemaphore::Wait(hsMilliseconds timeToWait)
 {
 #ifdef USE_SEMA  // SHOULDN'T THIS USE timeToWait??!?!? -rje
+    // shouldn't this use sem_timedwait? -dpogue (2012-03-04)
     hsAssert( timeToWait==kPosInfinity32, "sem_t does not support wait with timeout. #undef USE_SEMA and recompile." );
-    int status = ::sem_wait(&fPSema);
+    int status = sem_wait(fPSema);
     hsThrowIfOSErr(status);
     return true;
 #else
@@ -351,7 +371,7 @@ EXIT:
 void hsSemaphore::Signal()
 {
 #ifdef USE_SEMA
-    int status = ::sem_post(&fPSema);
+    int status = sem_post(fPSema);
     hsThrowIfOSErr(status);
 #else
     int status = ::pthread_mutex_lock(&fPMutex);