fixes #47 #48

* adjusted stacksize for mac os x
* handling status error conditions.
* fixed a nasty bug when calling thread::join() that did not properly handled the thread's retval.

Author: HerbertKoelman

include/pthread/thread.hpp

@@ -121,10 +121,11 @@ namespace pthread {
      * If the target thread is already terminated, the method returns immediately.
      *
      * This method does not itself cause a thread to be terminated.
-     *
+     * 
+     * @return the value returned by the joined thread (calling pthread_exit(void *retval))
      * @throws pthread_exception if this is not a thread or if thread_id == this_thread::get_id().
      */
-    int join();
+    void *join();
 
     /** @return true if this thread can be joined.
      */
@@ -166,10 +167,10 @@ namespace pthread {
      */
     void swap ( thread& other );
 
-    pthread_t      _thread;
-    pthread_attr_t _attr;
+    pthread_t      _thread; //!< thread identifier
+    pthread_attr_t _attr;   //!< thread attributes (stack size, ...)
 
-    thread_status  _status;
+    thread_status  _status; //!< thread status (@see thread_status)
   };
 
   /** base class of a thread.
@@ -245,9 +246,15 @@ namespace pthread {
 
     /** joins this thread.
      *
+     * @return value returned by the joined thread (pthread_exit(void *retval))
      * @throw pthread_exception if deadlock conditions are detected.
      */
-    int join() { return _thread->join() ;};
+    void *join() { return _thread->join() ;};
+    
+    /** @return true if this thread can be joined.
+     */
+    bool joinable() const { return _thread != 0 ;};
+
 
   private:
     pthread::thread *_thread;

src/thread.cpp

@@ -8,6 +8,7 @@
 
 #include "pthread/thread.hpp"
 #include <unistd.h>
+#include <cstdio>
 
 namespace pthread {
 
@@ -22,21 +23,36 @@ namespace pthread {
     }
   }
 
-  int thread::join () {
-    int rc = 0;
-    
-    if ( _thread == this_thread::get_id()){
-      throw pthread_exception("join failed, join yourself would endup in deadlock.");
-    }
-    if ( _status == thread_status::not_a_thread ){
-      throw pthread_exception("join failed, this is not a thread.");
-    }
+  void *thread::join () {
+    int    rc     = 0;
+    void *retval = 0;
 
-    if ( (rc = pthread_join(_thread, (void **)&_status)) != 0){
-      throw thread_exception("pthread_join failed.", rc );
+#if __cplusplus < 201103L
+    if ( _thread != NULL){
+#else
+    if ( _thread != nullptr){
+#endif
+      
+      if ( _thread == this_thread::get_id()){
+        throw pthread_exception("join failed, join yourself would endup in deadlock.");
+      }
+      
+      if ( _status == thread_status::not_a_thread ){
+        throw pthread_exception("join failed, this is not a thread.");
+      }
+      
+      if ( (rc = pthread_join(_thread, (void **)&retval)) != 0){
+        switch ( rc ) {
+          case EDEADLK:
+            throw thread_exception("EDEADLKpthread_join failed because of deadlock conditions.", rc );
+          case EINVAL:
+            throw thread_exception("EINVEL pthread_join failed not a joinable thread.", rc );
+          case ESRCH:
+            break; // thread has already ended.
+        }
+      }
     }
-    
-    return rc;
+    return retval;
   }
 
   int thread::cancel () {
@@ -72,7 +88,7 @@ namespace pthread {
     }
 
     if ( stack_size > 0 && (rc = pthread_attr_setstacksize(&_attr, stack_size)) != 0 ){
-      throw thread_exception("pthread_attr_setstacksize failed.", rc );
+      throw thread_exception("bad stacksize, check size passed to thread::thread; thread not started.", rc );
     }
 
     if ((rc = pthread_create(&_thread, &_attr, thread_startup_runnable, (void *) &work)) != 0){
@@ -128,7 +144,9 @@ namespace pthread {
   }
 
   thread_group::~thread_group(){
+    
     while(! _threads.empty()){
+      
 #if __cplusplus < 201103L
       std::auto_ptr<pthread::abstract_thread> pat(_threads.front());
 #else
@@ -137,9 +155,11 @@ namespace pthread {
 
       _threads.pop_front();
 
-      if ( _destructor_joins_first ){
+      if ( _destructor_joins_first && pat->joinable() ){
         try {
           pat->join();
+        } catch ( pthread_exception &err ){
+          printf("thread_group destructor failed to join one thread. %s, (%d) %s.\n", err.what(), err.pthread_errno(), err.pthread_errmsg());
         } catch ( ... ){};
       }
     }
@@ -158,7 +178,9 @@ namespace pthread {
 
   void thread_group::join(){
     for(auto iterator = _threads.begin(); iterator != _threads.end(); iterator++){
-      (*iterator)->join();
+      if ( (*iterator)->joinable() ){
+        (*iterator)->join(); 
+      }
     }
   }
 

tests/without-cpp11-pthread-tests.cpp

@@ -34,8 +34,7 @@ void message ( const std::string m){
 class worker: public pthread::abstract_thread {
 public:
 
-  worker(const std::string m = "anonymous worker", int sleep = 2*1000):abstract_thread(8000000),  msg(m), _sleep(sleep){
-//    msg.resize(msg.size()+1);    
+  worker(const std::string &m = "anonymous worker", int sleep = 2*1000):abstract_thread(8388608),  msg(m), _sleep(sleep){
   };
 
   ~worker(){
@@ -88,8 +87,8 @@ int main(int argc, const char * argv[]) {
   try {
     std::cout << "lib version: " << pthread::cpp_pthread_version() << std::endl;
 
-    int number_of_threads = 2;
-    if ( argc > 0 ){
+   int number_of_threads = 2;
+    if ( argc > 1 ){
        number_of_threads = atoi(argv[1]);
     }