thread.h

00001 /*------------------------------------------------------------------------
00002  *  Copyright 2007-2009 (c) Jeff Brown <spadix@users.sourceforge.net>
00003  *
00004  *  This file is part of the ZBar Bar Code Reader.
00005  *
00006  *  The ZBar Bar Code Reader is free software; you can redistribute it
00007  *  and/or modify it under the terms of the GNU Lesser Public License as
00008  *  published by the Free Software Foundation; either version 2.1 of
00009  *  the License, or (at your option) any later version.
00010  *
00011  *  The ZBar Bar Code Reader is distributed in the hope that it will be
00012  *  useful, but WITHOUT ANY WARRANTY; without even the implied warranty
00013  *  of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014  *  GNU Lesser Public License for more details.
00015  *
00016  *  You should have received a copy of the GNU Lesser Public License
00017  *  along with the ZBar Bar Code Reader; if not, write to the Free
00018  *  Software Foundation, Inc., 51 Franklin St, Fifth Floor,
00019  *  Boston, MA  02110-1301  USA
00020  *
00021  *  http://sourceforge.net/projects/zbar
00022  *------------------------------------------------------------------------*/
00023 #ifndef _ZBAR_THREAD_H_
00024 #define _ZBAR_THREAD_H_
00025 
00026 /* simple platform thread abstraction
00027  */
00028 
00029 #include <config.h>
00030 #include "event.h"
00031 
00032 #if defined(_WIN32)
00033 
00034 # include <windows.h>
00035 # define HAVE_THREADS
00036 # define ZTHREAD DWORD WINAPI
00037 
00038 typedef ZTHREAD (zbar_thread_proc_t)(void*);
00039 
00040 typedef DWORD zbar_thread_id_t;
00041 
00042 #elif defined(HAVE_LIBPTHREAD)
00043 
00044 # include <pthread.h>
00045 # include <signal.h>
00046 # define HAVE_THREADS
00047 # define ZTHREAD void*
00048 
00049 typedef ZTHREAD (zbar_thread_proc_t)(void*);
00050 
00051 typedef pthread_t zbar_thread_id_t;
00052 
00053 #else
00054 
00055 # undef HAVE_THREADS
00056 # undef ZTHREAD
00057 
00058 typedef void zbar_thread_proc_t;
00059 typedef int zbar_thread_id_t;
00060 
00061 #endif
00062 
00063 
00064 typedef struct zbar_thread_s {
00065     zbar_thread_id_t tid;
00066     int started, running;
00067     zbar_event_t notify, activity;
00068 } zbar_thread_t;
00069 
00070 
00071 #if defined(_WIN32)
00072 
00073 static inline void _zbar_thread_init (zbar_thread_t *thr)
00074 {
00075     thr->running = 1;
00076     _zbar_event_trigger(&thr->activity);
00077 }
00078 
00079 static inline zbar_thread_id_t _zbar_thread_self ()
00080 {
00081     return(GetCurrentThreadId());
00082 }
00083 
00084 static inline int _zbar_thread_is_self (zbar_thread_id_t tid)
00085 {
00086     return(tid == GetCurrentThreadId());
00087 }
00088 
00089 
00090 #elif defined(HAVE_LIBPTHREAD)
00091 
00092 static inline void _zbar_thread_init (zbar_thread_t *thr)
00093 {
00094     sigset_t sigs;
00095     sigfillset(&sigs);
00096     pthread_sigmask(SIG_BLOCK, &sigs, NULL);
00097     thr->running = 1;
00098     _zbar_event_trigger(&thr->activity);
00099 }
00100 
00101 static inline zbar_thread_id_t _zbar_thread_self (void)
00102 {
00103     return(pthread_self());
00104 }
00105 
00106 static inline int _zbar_thread_is_self (zbar_thread_id_t tid)
00107 {
00108     return(pthread_equal(tid, pthread_self()));
00109 }
00110 
00111 
00112 #else
00113 
00114 # define _zbar_thread_start(...) -1
00115 # define _zbar_thread_stop(...) 0
00116 # define _zbar_thread_self(...) 0
00117 # define _zbar_thread_is_self(...) 1
00118 
00119 #endif
00120 
00121 #ifdef HAVE_THREADS
00122 extern int _zbar_thread_start(zbar_thread_t*, zbar_thread_proc_t*,
00123                               void*, zbar_mutex_t*);
00124 extern int _zbar_thread_stop(zbar_thread_t*, zbar_mutex_t*);
00125 #endif
00126 
00127 #endif
00128