src/thread/pthread/SDL_systhread.c
author Sam Lantinga <slouken@libsdl.org>
Fri, 15 Feb 2013 08:47:44 -0800
changeset 6885 700f1b25f77f
parent 6641 45187a87d35b
child 7037 3fedf1f25b94
permissions -rw-r--r--
Happy New Year!
     1 /*
     2   Simple DirectMedia Layer
     3   Copyright (C) 1997-2013 Sam Lantinga <slouken@libsdl.org>
     4 
     5   This software is provided 'as-is', without any express or implied
     6   warranty.  In no event will the authors be held liable for any damages
     7   arising from the use of this software.
     8 
     9   Permission is granted to anyone to use this software for any purpose,
    10   including commercial applications, and to alter it and redistribute it
    11   freely, subject to the following restrictions:
    12 
    13   1. The origin of this software must not be misrepresented; you must not
    14      claim that you wrote the original software. If you use this software
    15      in a product, an acknowledgment in the product documentation would be
    16      appreciated but is not required.
    17   2. Altered source versions must be plainly marked as such, and must not be
    18      misrepresented as being the original software.
    19   3. This notice may not be removed or altered from any source distribution.
    20 */
    21 
    22 #include "SDL_config.h"
    23 
    24 #include <pthread.h>
    25 
    26 #if HAVE_PTHREAD_NP_H
    27 #include <pthread_np.h>
    28 #endif
    29 
    30 #include <signal.h>
    31 
    32 #ifdef __LINUX__
    33 #include <sys/time.h>
    34 #include <sys/resource.h>
    35 #include <sys/syscall.h>
    36 #include <unistd.h>
    37 #endif // __LINUX__
    38 
    39 #if defined(__LINUX__) || defined(__MACOSX__) || defined(__IPHONEOS__)
    40 #include <dlfcn.h>
    41 #ifndef RTLD_DEFAULT
    42 #define RTLD_DEFAULT NULL
    43 #endif
    44 #endif
    45 
    46 #include "SDL_platform.h"
    47 #include "SDL_thread.h"
    48 #include "../SDL_thread_c.h"
    49 #include "../SDL_systhread.h"
    50 #ifdef __ANDROID__
    51 #include "../../core/android/SDL_android.h"
    52 #endif
    53 
    54 #include "SDL_assert.h"
    55 
    56 /* List of signals to mask in the subthreads */
    57 static const int sig_list[] = {
    58     SIGHUP, SIGINT, SIGQUIT, SIGPIPE, SIGALRM, SIGTERM, SIGCHLD, SIGWINCH,
    59     SIGVTALRM, SIGPROF, 0
    60 };
    61 
    62 
    63 static void *
    64 RunThread(void *data)
    65 {
    66 #ifdef __ANDROID__
    67     Android_JNI_SetupThread();
    68 #endif
    69     SDL_RunThread(data);
    70     return NULL;
    71 }
    72 
    73 #if defined(__MACOSX__) || defined(__IPHONEOS__)
    74 static SDL_bool checked_setname = SDL_FALSE;
    75 static int (*ppthread_setname_np)(const char*) = NULL;
    76 #elif defined(__LINUX__)
    77 static SDL_bool checked_setname = SDL_FALSE;
    78 static int (*ppthread_setname_np)(pthread_t, const char*) = NULL;
    79 #endif
    80 int
    81 SDL_SYS_CreateThread(SDL_Thread * thread, void *args)
    82 {
    83     pthread_attr_t type;
    84 
    85     /* do this here before any threads exist, so there's no race condition. */
    86     #if defined(__MACOSX__) || defined(__IPHONEOS__) || defined(__LINUX__)
    87     if (!checked_setname) {
    88         void *fn = dlsym(RTLD_DEFAULT, "pthread_setname_np");
    89         #if defined(__MACOSX__) || defined(__IPHONEOS__)
    90         ppthread_setname_np = (int(*)(const char*)) fn;
    91         #elif defined(__LINUX__)
    92         ppthread_setname_np = (int(*)(pthread_t, const char*)) fn;
    93         #endif
    94         checked_setname = SDL_TRUE;
    95     }
    96     #endif
    97 
    98     /* Set the thread attributes */
    99     if (pthread_attr_init(&type) != 0) {
   100         SDL_SetError("Couldn't initialize pthread attributes");
   101         return (-1);
   102     }
   103     pthread_attr_setdetachstate(&type, PTHREAD_CREATE_JOINABLE);
   104 
   105     /* Create the thread and go! */
   106     if (pthread_create(&thread->handle, &type, RunThread, args) != 0) {
   107         SDL_SetError("Not enough resources to create thread");
   108         return (-1);
   109     }
   110 
   111     return (0);
   112 }
   113 
   114 void
   115 SDL_SYS_SetupThread(const char *name)
   116 {
   117     int i;
   118     sigset_t mask;
   119 
   120     if (name != NULL) {
   121         #if defined(__MACOSX__) || defined(__IPHONEOS__) || defined(__LINUX__)
   122         SDL_assert(checked_setname);
   123         if (ppthread_setname_np != NULL) {
   124             #if defined(__MACOSX__) || defined(__IPHONEOS__)
   125             ppthread_setname_np(name);
   126             #elif defined(__LINUX__)
   127             ppthread_setname_np(pthread_self(), name);
   128             #endif
   129         }
   130         #elif HAVE_PTHREAD_SETNAME_NP
   131             pthread_setname_np(pthread_self(), name);
   132         #elif HAVE_PTHREAD_SET_NAME_NP
   133             pthread_set_name_np(pthread_self(), name);
   134         #endif
   135     }
   136 
   137     /* Mask asynchronous signals for this thread */
   138     sigemptyset(&mask);
   139     for (i = 0; sig_list[i]; ++i) {
   140         sigaddset(&mask, sig_list[i]);
   141     }
   142     pthread_sigmask(SIG_BLOCK, &mask, 0);
   143 
   144 #ifdef PTHREAD_CANCEL_ASYNCHRONOUS
   145     /* Allow ourselves to be asynchronously cancelled */
   146     {
   147         int oldstate;
   148         pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, &oldstate);
   149     }
   150 #endif
   151 }
   152 
   153 SDL_threadID
   154 SDL_ThreadID(void)
   155 {
   156     return ((SDL_threadID) pthread_self());
   157 }
   158 
   159 int
   160 SDL_SYS_SetThreadPriority(SDL_ThreadPriority priority)
   161 {
   162 #ifdef __LINUX__
   163     int value;
   164 
   165     if (priority == SDL_THREAD_PRIORITY_LOW) {
   166         value = 19;
   167     } else if (priority == SDL_THREAD_PRIORITY_HIGH) {
   168         value = -20;
   169     } else {
   170         value = 0;
   171     }
   172     if (setpriority(PRIO_PROCESS, syscall(SYS_gettid), value) < 0) {
   173         /* Note that this fails if you're trying to set high priority
   174            and you don't have root permission. BUT DON'T RUN AS ROOT!
   175          */
   176         SDL_SetError("setpriority() failed");
   177         return -1;
   178     }
   179     return 0;
   180 #else
   181     struct sched_param sched;
   182     int policy;
   183     pthread_t thread = pthread_self();
   184 
   185     if (pthread_getschedparam(thread, &policy, &sched) < 0) {
   186         SDL_SetError("pthread_getschedparam() failed");
   187         return -1;
   188     }
   189     if (priority == SDL_THREAD_PRIORITY_LOW) {
   190         sched.sched_priority = sched_get_priority_min(policy);
   191     } else if (priority == SDL_THREAD_PRIORITY_HIGH) {
   192         sched.sched_priority = sched_get_priority_max(policy);
   193     } else {
   194         int min_priority = sched_get_priority_min(policy);
   195         int max_priority = sched_get_priority_max(policy);
   196         sched.sched_priority = (min_priority + (max_priority - min_priority) / 2);
   197     }
   198     if (pthread_setschedparam(thread, policy, &sched) < 0) {
   199         SDL_SetError("pthread_setschedparam() failed");
   200         return -1;
   201     }
   202     return 0;
   203 #endif /* linux */
   204 }
   205 
   206 void
   207 SDL_SYS_WaitThread(SDL_Thread * thread)
   208 {
   209     pthread_join(thread->handle, 0);
   210 }
   211 
   212 /* vi: set ts=4 sw=4 expandtab: */