Add pthread_join(3).

libpthread/Makefile

@@ -30,6 +30,7 @@ pthread_equal.o \
 pthread_exit.o \
 pthread_getspecific.o \
 pthread_initialize.o \
+pthread_join.o \
 pthread_key_create.o \
 pthread_key_delete.o \
 pthread_mutexattr_destroy.o \

libpthread/include/pthread.h

@@ -138,8 +138,10 @@ typedef __pthread_t pthread_t;
 struct pthread
 {
 	struct uthread uthread;
+	pthread_mutex_t join_lock;
 	void* (*entry_function)(void*);
 	void* entry_cookie;
+	void* exit_result;
 	void** keys;
 	size_t keys_length;
 };
@@ -242,7 +244,7 @@ void pthread_exit(void*);
 /* TODO: pthread_getcpuclockid */
 /* TODO: pthread_getschedparam */
 void* pthread_getspecific(pthread_key_t);
-/* TODO: pthread_join */
+int pthread_join(pthread_t, void**);
 int pthread_key_create(pthread_key_t*, void (*)(void*));
 int pthread_key_delete(pthread_key_t);
 /* TODO: pthread_mutex_consistent */

libpthread/pthread_create.c++

@@ -203,6 +203,10 @@ int pthread_create(pthread_t* restrict thread_ptr,
 	thread->uthread.tls_size = tls_size;
 	thread->uthread.arg_mmap = self->uthread.arg_mmap;
 	thread->uthread.arg_size = self->uthread.arg_size;
+	thread->join_lock = PTHREAD_NORMAL_MUTEX_INITIALIZER_NP;
+	thread->join_lock.lock = 1 /* LOCKED_VALUE */;
+	thread->join_lock.type = PTHREAD_MUTEX_NORMAL;
+	thread->join_lock.owner = (unsigned long) thread;
 	thread->entry_function = entry_function;
 	thread->entry_cookie = entry_cookie;
 

libpthread/pthread_exit.c++

@@ -31,7 +31,7 @@
 
 extern "C"
 __attribute__((__noreturn__))
-void pthread_exit(void* /*return_value*/)
+void pthread_exit(void* return_value)
 {
 	struct pthread* thread = pthread_self();
 
@@ -61,10 +61,13 @@ void pthread_exit(void* /*return_value*/)
 	pthread_mutex_unlock(&__pthread_num_threads_lock);
 	if ( num_threads == 1 )
 		exit(0);
+	thread->exit_result = return_value;
 	struct exit_thread extended;
 	memset(&extended, 0, sizeof(extended));
 	extended.unmap_from = thread->uthread.stack_mmap;
 	extended.unmap_size = thread->uthread.stack_size;
-	exit_thread(0, EXIT_THREAD_UNMAP, &extended);
+	extended.zero_from = &thread->join_lock.lock;
+	extended.zero_size = sizeof(thread->join_lock.lock);
+	exit_thread(0, EXIT_THREAD_UNMAP | EXIT_THREAD_ZERO, &extended);
 	__builtin_unreachable();
 }

libpthread/pthread_initialize.c++

@@ -72,4 +72,10 @@ static void elf_note_sortix_pthread_size()
 
 extern "C" void pthread_initialize(void)
 {
+	struct pthread* self = pthread_self();
+
+	self->join_lock = PTHREAD_NORMAL_MUTEX_INITIALIZER_NP;
+	self->join_lock.lock = 1 /* LOCKED_VALUE */;
+	self->join_lock.type = PTHREAD_MUTEX_NORMAL;
+	self->join_lock.owner = (unsigned long) self;
 }

libpthread/pthread_join.c++

@@ -0,0 +1,40 @@
+/*******************************************************************************
+
+    Copyright(C) Jonas 'Sortie' Termansen 2014.
+
+    This file is part of Sortix libpthread.
+
+    Sortix libpthread is free software: you can redistribute it and/or modify it
+    under the terms of the GNU Lesser General Public License as published by the
+    Free Software Foundation, either version 3 of the License, or (at your
+    option) any later version.
+
+    Sortix libpthread is distributed in the hope that it will be useful, but
+    WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+    or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
+    License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with Sortix libpthread. If not, see <http://www.gnu.org/licenses/>.
+
+    pthread_join.c++
+    Wait for thread termination.
+
+*******************************************************************************/
+
+#include <sys/mman.h>
+
+#include <pthread.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+extern "C" int pthread_join(pthread_t thread, void** result_ptr)
+{
+	pthread_mutex_lock(&thread->join_lock);
+	pthread_mutex_unlock(&thread->join_lock);
+	void* result = thread->exit_result;
+	munmap(thread->uthread.tls_mmap, thread->uthread.tls_size);
+	if ( result_ptr )
+		*result_ptr = result;
+	return 0;
+}