Fixed crash if initialization of EGL failed but was tried again later.

The internal function SDL_EGL_LoadLibrary() did not delete and remove a mostly
uninitialized data structure if loading the library first failed. A later try to
use EGL then skipped initialization and assumed it was previously successful
because the data structure now already existed. This led to at least one crash
in the internal function SDL_EGL_ChooseConfig() because a NULL pointer was
dereferenced to make a call to eglBindAPI().

src/thread/pthread/SDL_syscond.c

@@ -0,0 +1,158 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2015 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+#include "../../SDL_internal.h"
+
+#include <sys/time.h>
+#include <time.h>
+#include <unistd.h>
+#include <errno.h>
+#include <pthread.h>
+
+#include "SDL_thread.h"
+#include "SDL_sysmutex_c.h"
+
+struct SDL_cond
+{
+    pthread_cond_t cond;
+};
+
+/* Create a condition variable */
+SDL_cond *
+SDL_CreateCond(void)
+{
+    SDL_cond *cond;
+
+    cond = (SDL_cond *) SDL_malloc(sizeof(SDL_cond));
+    if (cond) {
+        if (pthread_cond_init(&cond->cond, NULL) < 0) {
+            SDL_SetError("pthread_cond_init() failed");
+            SDL_free(cond);
+            cond = NULL;
+        }
+    }
+    return (cond);
+}
+
+/* Destroy a condition variable */
+void
+SDL_DestroyCond(SDL_cond * cond)
+{
+    if (cond) {
+        pthread_cond_destroy(&cond->cond);
+        SDL_free(cond);
+    }
+}
+
+/* Restart one of the threads that are waiting on the condition variable */
+int
+SDL_CondSignal(SDL_cond * cond)
+{
+    int retval;
+
+    if (!cond) {
+        return SDL_SetError("Passed a NULL condition variable");
+    }
+
+    retval = 0;
+    if (pthread_cond_signal(&cond->cond) != 0) {
+        return SDL_SetError("pthread_cond_signal() failed");
+    }
+    return retval;
+}
+
+/* Restart all threads that are waiting on the condition variable */
+int
+SDL_CondBroadcast(SDL_cond * cond)
+{
+    int retval;
+
+    if (!cond) {
+        return SDL_SetError("Passed a NULL condition variable");
+    }
+
+    retval = 0;
+    if (pthread_cond_broadcast(&cond->cond) != 0) {
+        return SDL_SetError("pthread_cond_broadcast() failed");
+    }
+    return retval;
+}
+
+int
+SDL_CondWaitTimeout(SDL_cond * cond, SDL_mutex * mutex, Uint32 ms)
+{
+    int retval;
+#ifndef HAVE_CLOCK_GETTIME
+    struct timeval delta;
+#endif
+    struct timespec abstime;
+
+    if (!cond) {
+        return SDL_SetError("Passed a NULL condition variable");
+    }
+
+#ifdef HAVE_CLOCK_GETTIME
+    clock_gettime(CLOCK_REALTIME, &abstime);
+
+    abstime.tv_nsec += (ms % 1000) * 1000000;
+    abstime.tv_sec += ms / 1000;
+#else
+    gettimeofday(&delta, NULL);
+
+    abstime.tv_sec = delta.tv_sec + (ms / 1000);
+    abstime.tv_nsec = (delta.tv_usec + (ms % 1000) * 1000) * 1000;
+#endif
+    if (abstime.tv_nsec > 1000000000) {
+        abstime.tv_sec += 1;
+        abstime.tv_nsec -= 1000000000;
+    }
+
+  tryagain:
+    retval = pthread_cond_timedwait(&cond->cond, &mutex->id, &abstime);
+    switch (retval) {
+    case EINTR:
+        goto tryagain;
+        break;
+    case ETIMEDOUT:
+        retval = SDL_MUTEX_TIMEDOUT;
+        break;
+    case 0:
+        break;
+    default:
+        retval = SDL_SetError("pthread_cond_timedwait() failed");
+    }
+    return retval;
+}
+
+/* Wait on the condition variable, unlocking the provided mutex.
+   The mutex must be locked before entering this function!
+ */
+int
+SDL_CondWait(SDL_cond * cond, SDL_mutex * mutex)
+{
+    if (!cond) {
+        return SDL_SetError("Passed a NULL condition variable");
+    } else if (pthread_cond_wait(&cond->cond, &mutex->id) != 0) {
+        return SDL_SetError("pthread_cond_wait() failed");
+    }
+    return 0;
+}
+
+/* vi: set ts=4 sw=4 expandtab: */

src/thread/pthread/SDL_sysmutex.c

@@ -0,0 +1,195 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2015 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+#include "../../SDL_internal.h"
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+#include <errno.h>
+#include <pthread.h>
+
+#include "SDL_thread.h"
+
+#if !SDL_THREAD_PTHREAD_RECURSIVE_MUTEX && \
+    !SDL_THREAD_PTHREAD_RECURSIVE_MUTEX_NP
+#define FAKE_RECURSIVE_MUTEX 1
+#endif
+
+struct SDL_mutex
+{
+    pthread_mutex_t id;
+#if FAKE_RECURSIVE_MUTEX
+    int recursive;
+    pthread_t owner;
+#endif
+};
+
+SDL_mutex *
+SDL_CreateMutex(void)
+{
+    SDL_mutex *mutex;
+    pthread_mutexattr_t attr;
+
+    /* Allocate the structure */
+    mutex = (SDL_mutex *) SDL_calloc(1, sizeof(*mutex));
+    if (mutex) {
+        pthread_mutexattr_init(&attr);
+#if SDL_THREAD_PTHREAD_RECURSIVE_MUTEX
+        pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE);
+#elif SDL_THREAD_PTHREAD_RECURSIVE_MUTEX_NP
+        pthread_mutexattr_setkind_np(&attr, PTHREAD_MUTEX_RECURSIVE_NP);
+#else
+        /* No extra attributes necessary */
+#endif
+        if (pthread_mutex_init(&mutex->id, &attr) != 0) {
+            SDL_SetError("pthread_mutex_init() failed");
+            SDL_free(mutex);
+            mutex = NULL;
+        }
+    } else {
+        SDL_OutOfMemory();
+    }
+    return (mutex);
+}
+
+void
+SDL_DestroyMutex(SDL_mutex * mutex)
+{
+    if (mutex) {
+        pthread_mutex_destroy(&mutex->id);
+        SDL_free(mutex);
+    }
+}
+
+/* Lock the mutex */
+int
+SDL_LockMutex(SDL_mutex * mutex)
+{
+#if FAKE_RECURSIVE_MUTEX
+    pthread_t this_thread;
+#endif
+
+    if (mutex == NULL) {
+        return SDL_SetError("Passed a NULL mutex");
+    }
+
+#if FAKE_RECURSIVE_MUTEX
+    this_thread = pthread_self();
+    if (mutex->owner == this_thread) {
+        ++mutex->recursive;
+    } else {
+        /* The order of operations is important.
+           We set the locking thread id after we obtain the lock
+           so unlocks from other threads will fail.
+         */
+        if (pthread_mutex_lock(&mutex->id) == 0) {
+            mutex->owner = this_thread;
+            mutex->recursive = 0;
+        } else {
+            return SDL_SetError("pthread_mutex_lock() failed");
+        }
+    }
+#else
+    if (pthread_mutex_lock(&mutex->id) < 0) {
+        return SDL_SetError("pthread_mutex_lock() failed");
+    }
+#endif
+    return 0;
+}
+
+int
+SDL_TryLockMutex(SDL_mutex * mutex)
+{
+    int retval;
+#if FAKE_RECURSIVE_MUTEX
+    pthread_t this_thread;
+#endif
+
+    if (mutex == NULL) {
+        return SDL_SetError("Passed a NULL mutex");
+    }
+
+    retval = 0;
+#if FAKE_RECURSIVE_MUTEX
+    this_thread = pthread_self();
+    if (mutex->owner == this_thread) {
+        ++mutex->recursive;
+    } else {
+        /* The order of operations is important.
+         We set the locking thread id after we obtain the lock
+         so unlocks from other threads will fail.
+         */
+        if (pthread_mutex_lock(&mutex->id) == 0) {
+            mutex->owner = this_thread;
+            mutex->recursive = 0;
+        } else if (errno == EBUSY) {
+            retval = SDL_MUTEX_TIMEDOUT;
+        } else {
+            retval = SDL_SetError("pthread_mutex_trylock() failed");
+        }
+    }
+#else
+    if (pthread_mutex_trylock(&mutex->id) != 0) {
+        if (errno == EBUSY) {
+            retval = SDL_MUTEX_TIMEDOUT;
+        } else {
+            retval = SDL_SetError("pthread_mutex_trylock() failed");
+        }
+    }
+#endif
+    return retval;
+}
+
+int
+SDL_UnlockMutex(SDL_mutex * mutex)
+{
+    if (mutex == NULL) {
+        return SDL_SetError("Passed a NULL mutex");
+    }
+
+#if FAKE_RECURSIVE_MUTEX
+    /* We can only unlock the mutex if we own it */
+    if (pthread_self() == mutex->owner) {
+        if (mutex->recursive) {
+            --mutex->recursive;
+        } else {
+            /* The order of operations is important.
+               First reset the owner so another thread doesn't lock
+               the mutex and set the ownership before we reset it,
+               then release the lock semaphore.
+             */
+            mutex->owner = 0;
+            pthread_mutex_unlock(&mutex->id);
+        }
+    } else {
+        return SDL_SetError("mutex not owned by this thread");
+    }
+
+#else
+    if (pthread_mutex_unlock(&mutex->id) < 0) {
+        return SDL_SetError("pthread_mutex_unlock() failed");
+    }
+#endif /* FAKE_RECURSIVE_MUTEX */
+
+    return 0;
+}
+
+/* vi: set ts=4 sw=4 expandtab: */

src/thread/pthread/SDL_sysmutex_c.h

@@ -0,0 +1,32 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2015 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+#include "../../SDL_internal.h"
+
+#ifndef _SDL_mutex_c_h
+#define _SDL_mutex_c_h
+
+struct SDL_mutex
+{
+    pthread_mutex_t id;
+};
+
+#endif /* _SDL_mutex_c_h */
+/* vi: set ts=4 sw=4 expandtab: */

src/thread/pthread/SDL_syssem.c

@@ -0,0 +1,209 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2015 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+#include "../../SDL_internal.h"
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+#include <errno.h>
+#include <pthread.h>
+#include <semaphore.h>
+#include <sys/time.h>
+#include <time.h>
+
+#include "SDL_thread.h"
+#include "SDL_timer.h"
+
+/* Wrapper around POSIX 1003.1b semaphores */
+
+#if defined(__MACOSX__) || defined(__IPHONEOS__)
+/* Mac OS X doesn't support sem_getvalue() as of version 10.4 */
+#include "../generic/SDL_syssem.c"
+#else
+
+struct SDL_semaphore
+{
+    sem_t sem;
+};
+
+/* Create a semaphore, initialized with value */
+SDL_sem *
+SDL_CreateSemaphore(Uint32 initial_value)
+{
+    SDL_sem *sem = (SDL_sem *) SDL_malloc(sizeof(SDL_sem));
+    if (sem) {
+        if (sem_init(&sem->sem, 0, initial_value) < 0) {
+            SDL_SetError("sem_init() failed");
+            SDL_free(sem);
+            sem = NULL;
+        }
+    } else {
+        SDL_OutOfMemory();
+    }
+    return sem;
+}
+
+void
+SDL_DestroySemaphore(SDL_sem * sem)
+{
+    if (sem) {
+        sem_destroy(&sem->sem);
+        SDL_free(sem);
+    }
+}
+
+int
+SDL_SemTryWait(SDL_sem * sem)
+{
+    int retval;
+
+    if (!sem) {
+        return SDL_SetError("Passed a NULL semaphore");
+    }
+    retval = SDL_MUTEX_TIMEDOUT;
+    if (sem_trywait(&sem->sem) == 0) {
+        retval = 0;
+    }
+    return retval;
+}
+
+int
+SDL_SemWait(SDL_sem * sem)
+{
+    int retval;
+
+    if (!sem) {
+        return SDL_SetError("Passed a NULL semaphore");
+    }
+
+    retval = sem_wait(&sem->sem);
+    if (retval < 0) {
+        retval = SDL_SetError("sem_wait() failed");
+    }
+    return retval;
+}
+
+int
+SDL_SemWaitTimeout(SDL_sem * sem, Uint32 timeout)
+{
+    int retval;
+#ifdef HAVE_SEM_TIMEDWAIT
+#ifndef HAVE_CLOCK_GETTIME
+    struct timeval now;
+#endif
+    struct timespec ts_timeout;
+#else
+    Uint32 end;
+#endif
+
+    if (!sem) {
+        return SDL_SetError("Passed a NULL semaphore");
+    }
+
+    /* Try the easy cases first */
+    if (timeout == 0) {
+        return SDL_SemTryWait(sem);
+    }
+    if (timeout == SDL_MUTEX_MAXWAIT) {
+        return SDL_SemWait(sem);
+    }
+
+#ifdef HAVE_SEM_TIMEDWAIT
+    /* Setup the timeout. sem_timedwait doesn't wait for
+    * a lapse of time, but until we reach a certain time.
+    * This time is now plus the timeout.
+    */
+#ifdef HAVE_CLOCK_GETTIME
+    clock_gettime(CLOCK_REALTIME, &ts_timeout);
+
+    /* Add our timeout to current time */
+    ts_timeout.tv_nsec += (timeout % 1000) * 1000000;
+    ts_timeout.tv_sec += timeout / 1000;
+#else
+    gettimeofday(&now, NULL);
+
+    /* Add our timeout to current time */
+    ts_timeout.tv_sec = now.tv_sec + (timeout / 1000);
+    ts_timeout.tv_nsec = (now.tv_usec + (timeout % 1000) * 1000) * 1000;
+#endif
+
+    /* Wrap the second if needed */
+    if (ts_timeout.tv_nsec > 1000000000) {
+        ts_timeout.tv_sec += 1;
+        ts_timeout.tv_nsec -= 1000000000;
+    }
+
+    /* Wait. */
+    do {
+        retval = sem_timedwait(&sem->sem, &ts_timeout);
+    } while (retval < 0 && errno == EINTR);
+
+    if (retval < 0) {
+        if (errno == ETIMEDOUT) {
+            retval = SDL_MUTEX_TIMEDOUT;
+        } else {
+            SDL_SetError("sem_timedwait returned an error: %s", strerror(errno));
+        }
+    }
+#else
+    end = SDL_GetTicks() + timeout;
+    while ((retval = SDL_SemTryWait(sem)) == SDL_MUTEX_TIMEDOUT) {
+        if (SDL_TICKS_PASSED(SDL_GetTicks(), end)) {
+            break;
+        }
+        SDL_Delay(1);
+    }
+#endif /* HAVE_SEM_TIMEDWAIT */
+
+    return retval;
+}
+
+Uint32
+SDL_SemValue(SDL_sem * sem)
+{
+    int ret = 0;
+    if (sem) {
+        sem_getvalue(&sem->sem, &ret);
+        if (ret < 0) {
+            ret = 0;
+        }
+    }
+    return (Uint32) ret;
+}
+
+int
+SDL_SemPost(SDL_sem * sem)
+{
+    int retval;
+
+    if (!sem) {
+        return SDL_SetError("Passed a NULL semaphore");
+    }
+
+    retval = sem_post(&sem->sem);
+    if (retval < 0) {
+        SDL_SetError("sem_post() failed");
+    }
+    return retval;
+}
+
+#endif /* __MACOSX__ */
+/* vi: set ts=4 sw=4 expandtab: */

src/thread/pthread/SDL_systhread.c

@@ -0,0 +1,246 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2015 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#include "../../SDL_internal.h"
+
+#include <pthread.h>
+
+#if HAVE_PTHREAD_NP_H
+#include <pthread_np.h>
+#endif
+
+#include <signal.h>
+
+#ifdef __LINUX__
+#include <sys/time.h>
+#include <sys/resource.h>
+#include <sys/syscall.h>
+#include <unistd.h>
+#endif /* __LINUX__ */
+
+#if defined(__LINUX__) || defined(__MACOSX__) || defined(__IPHONEOS__)
+#include <dlfcn.h>
+#ifndef RTLD_DEFAULT
+#define RTLD_DEFAULT NULL
+#endif
+#endif
+
+#include "SDL_platform.h"
+#include "SDL_thread.h"
+#include "SDL_hints.h"
+#include "../SDL_thread_c.h"
+#include "../SDL_systhread.h"
+#ifdef __ANDROID__
+#include "../../core/android/SDL_android.h"
+#endif
+
+#ifdef __HAIKU__
+#include <be/kernel/OS.h>
+#endif
+
+#include "SDL_assert.h"
+
+#ifndef __NACL__
+/* List of signals to mask in the subthreads */
+static const int sig_list[] = {
+    SIGHUP, SIGINT, SIGQUIT, SIGPIPE, SIGALRM, SIGTERM, SIGCHLD, SIGWINCH,
+    SIGVTALRM, SIGPROF, 0
+};
+#endif
+
+static void *
+RunThread(void *data)
+{
+#ifdef __ANDROID__
+    Android_JNI_SetupThread();
+#endif
+    SDL_RunThread(data);
+    return NULL;
+}
+
+#if defined(__MACOSX__) || defined(__IPHONEOS__)
+static SDL_bool checked_setname = SDL_FALSE;
+static int (*ppthread_setname_np)(const char*) = NULL;
+#elif defined(__LINUX__)
+static SDL_bool checked_setname = SDL_FALSE;
+static int (*ppthread_setname_np)(pthread_t, const char*) = NULL;
+#endif
+int
+SDL_SYS_CreateThread(SDL_Thread * thread, void *args)
+{
+    pthread_attr_t type;
+    size_t ss;
+    const char *hint = SDL_GetHint(SDL_HINT_THREAD_STACK_SIZE);
+
+    /* do this here before any threads exist, so there's no race condition. */
+    #if defined(__MACOSX__) || defined(__IPHONEOS__) || defined(__LINUX__)
+    if (!checked_setname) {
+        void *fn = dlsym(RTLD_DEFAULT, "pthread_setname_np");
+        #if defined(__MACOSX__) || defined(__IPHONEOS__)
+        ppthread_setname_np = (int(*)(const char*)) fn;
+        #elif defined(__LINUX__)
+        ppthread_setname_np = (int(*)(pthread_t, const char*)) fn;
+        #endif
+        checked_setname = SDL_TRUE;
+    }
+    #endif
+
+    /* Set the thread attributes */
+    if (pthread_attr_init(&type) != 0) {
+        return SDL_SetError("Couldn't initialize pthread attributes");
+    }
+    pthread_attr_setdetachstate(&type, PTHREAD_CREATE_JOINABLE);
+    
+    /* If the SDL_HINT_THREAD_STACK_SIZE exists and it seems to be a positive number, use it */
+    if (hint && hint[0] >= '0' && hint[0] <= '9') {
+        const size_t stacksize = (size_t) SDL_atoi(hint);
+        if (stacksize > 0) {
+            pthread_attr_setstacksize(&type, stacksize);
+        }
+    }
+    
+    pthread_attr_getstacksize(&type, &ss);
+
+    /* Create the thread and go! */
+    if (pthread_create(&thread->handle, &type, RunThread, args) != 0) {
+        return SDL_SetError("Not enough resources to create thread");
+    }
+
+    return 0;
+}
+
+void
+SDL_SYS_SetupThread(const char *name)
+{
+#if !defined(__ANDROID__) && !defined(__NACL__)
+    int i;
+    sigset_t mask;
+#endif /* !__ANDROID__ && !__NACL__ */
+
+    if (name != NULL) {
+        #if defined(__MACOSX__) || defined(__IPHONEOS__) || defined(__LINUX__)
+        SDL_assert(checked_setname);
+        if (ppthread_setname_np != NULL) {
+            #if defined(__MACOSX__) || defined(__IPHONEOS__)
+            ppthread_setname_np(name);
+            #elif defined(__LINUX__)
+            ppthread_setname_np(pthread_self(), name);
+            #endif
+        }
+        #elif HAVE_PTHREAD_SETNAME_NP
+            pthread_setname_np(pthread_self(), name);
+        #elif HAVE_PTHREAD_SET_NAME_NP
+            pthread_set_name_np(pthread_self(), name);
+        #elif defined(__HAIKU__)
+            /* The docs say the thread name can't be longer than B_OS_NAME_LENGTH. */
+            char namebuf[B_OS_NAME_LENGTH];
+            SDL_snprintf(namebuf, sizeof (namebuf), "%s", name);
+            namebuf[sizeof (namebuf) - 1] = '\0';
+            rename_thread(find_thread(NULL), namebuf);
+        #endif
+    }
+
+   /* NativeClient does not yet support signals.*/
+#if !defined(__ANDROID__) && !defined(__NACL__)
+    /* Mask asynchronous signals for this thread */
+    sigemptyset(&mask);
+    for (i = 0; sig_list[i]; ++i) {
+        sigaddset(&mask, sig_list[i]);
+    }
+    pthread_sigmask(SIG_BLOCK, &mask, 0);
+#endif /* !__ANDROID__ && !__NACL__ */
+
+
+#ifdef PTHREAD_CANCEL_ASYNCHRONOUS
+    /* Allow ourselves to be asynchronously cancelled */
+    {
+        int oldstate;
+        pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, &oldstate);
+    }
+#endif
+}
+
+SDL_threadID
+SDL_ThreadID(void)
+{
+    return ((SDL_threadID) pthread_self());
+}
+
+int
+SDL_SYS_SetThreadPriority(SDL_ThreadPriority priority)
+{
+#if __NACL__ 
+    /* FIXME: Setting thread priority does not seem to be supported in NACL */
+    return 0;
+#elif __LINUX__
+    int value;
+
+    if (priority == SDL_THREAD_PRIORITY_LOW) {
+        value = 19;
+    } else if (priority == SDL_THREAD_PRIORITY_HIGH) {
+        value = -20;
+    } else {
+        value = 0;
+    }
+    if (setpriority(PRIO_PROCESS, syscall(SYS_gettid), value) < 0) {
+        /* Note that this fails if you're trying to set high priority
+           and you don't have root permission. BUT DON'T RUN AS ROOT!
+         */
+        return SDL_SetError("setpriority() failed");
+    }
+    return 0;
+#else
+    struct sched_param sched;
+    int policy;
+    pthread_t thread = pthread_self();
+
+    if (pthread_getschedparam(thread, &policy, &sched) < 0) {
+        return SDL_SetError("pthread_getschedparam() failed");
+    }
+    if (priority == SDL_THREAD_PRIORITY_LOW) {
+        sched.sched_priority = sched_get_priority_min(policy);
+    } else if (priority == SDL_THREAD_PRIORITY_HIGH) {
+        sched.sched_priority = sched_get_priority_max(policy);
+    } else {
+        int min_priority = sched_get_priority_min(policy);
+        int max_priority = sched_get_priority_max(policy);
+        sched.sched_priority = (min_priority + (max_priority - min_priority) / 2);
+    }
+    if (pthread_setschedparam(thread, policy, &sched) < 0) {
+        return SDL_SetError("pthread_setschedparam() failed");
+    }
+    return 0;
+#endif /* linux */
+}
+
+void
+SDL_SYS_WaitThread(SDL_Thread * thread)
+{
+    pthread_join(thread->handle, 0);
+}
+
+void
+SDL_SYS_DetachThread(SDL_Thread * thread)
+{
+    pthread_detach(thread->handle);
+}
+
+/* vi: set ts=4 sw=4 expandtab: */

src/thread/pthread/SDL_systhread_c.h

@@ -0,0 +1,27 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2015 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+#include "../../SDL_internal.h"
+
+#include <pthread.h>
+
+typedef pthread_t SYS_ThreadHandle;
+
+/* vi: set ts=4 sw=4 expandtab: */

src/thread/pthread/SDL_systls.c

@@ -0,0 +1,69 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2015 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+#include "../../SDL_internal.h"
+#include "SDL_thread.h"
+#include "../SDL_thread_c.h"
+
+#include <pthread.h>
+
+
+#define INVALID_PTHREAD_KEY ((pthread_key_t)-1)
+
+static pthread_key_t thread_local_storage = INVALID_PTHREAD_KEY;
+static SDL_bool generic_local_storage = SDL_FALSE;
+
+SDL_TLSData *
+SDL_SYS_GetTLSData()
+{
+    if (thread_local_storage == INVALID_PTHREAD_KEY && !generic_local_storage) {
+        static SDL_SpinLock lock;
+        SDL_AtomicLock(&lock);
+        if (thread_local_storage == INVALID_PTHREAD_KEY && !generic_local_storage) {
+            pthread_key_t storage;
+            if (pthread_key_create(&storage, NULL) == 0) {
+                SDL_MemoryBarrierRelease();
+                thread_local_storage = storage;
+            } else {
+                generic_local_storage = SDL_TRUE;
+            }
+        }
+        SDL_AtomicUnlock(&lock);
+    }
+    if (generic_local_storage) {
+        return SDL_Generic_GetTLSData();
+    }
+    SDL_MemoryBarrierAcquire();
+    return (SDL_TLSData *)pthread_getspecific(thread_local_storage);
+}
+
+int
+SDL_SYS_SetTLSData(SDL_TLSData *data)
+{
+    if (generic_local_storage) {
+        return SDL_Generic_SetTLSData(data);
+    }
+    if (pthread_setspecific(thread_local_storage, data) != 0) {
+        return SDL_SetError("pthread_setspecific() failed");
+    }
+    return 0;
+}
+
+/* vi: set ts=4 sw=4 expandtab: */