Add thread-safety primitives

This commit is contained in:
Behdad Esfahbod 2012-10-07 14:24:28 -04:00
parent f6d8306e56
commit 814871b2aa
5 changed files with 254 additions and 2 deletions

View File

@ -5,6 +5,7 @@ Copyright © 2005 Patrick Lam
Copyright © 2009 Roozbeh Pournader
Copyright © 2008,2009 Red Hat, Inc.
Copyright © 2008 Danilo Šegan
Copyright © 2012 Google, Inc.
Permission to use, copy, modify, distribute, and sell this software and its

View File

@ -123,6 +123,7 @@ EXTRA_DIST += \
libfontconfig_la_SOURCES = \
fcarch.h \
fcatomic.c \
fcatomic.h \
fcblanks.c \
fccache.c \
fccfg.c \
@ -138,6 +139,7 @@ libfontconfig_la_SOURCES = \
fclist.c \
fcmatch.c \
fcmatrix.c \
fcmutex.h \
fcname.c \
fcobjs.c \
fcobjs.h \

123
src/fcatomic.h Normal file
View File

@ -0,0 +1,123 @@
/*
* Mutex operations. Originally copied from HarfBuzz.
*
* Copyright © 2007 Chris Wilson
* Copyright © 2009,2010 Red Hat, Inc.
* Copyright © 2011,2012 Google, Inc.
*
* This is part of HarfBuzz, a text shaping library.
*
* Permission is hereby granted, without written agreement and without
* license or royalty fees, to use, copy, modify, and distribute this
* software and its documentation for any purpose, provided that the
* above copyright notice and the following two paragraphs appear in
* all copies of this software.
*
* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*
* Contributor(s):
* Chris Wilson <chris@chris-wilson.co.uk>
* Red Hat Author(s): Behdad Esfahbod
* Google Author(s): Behdad Esfahbod
*/
#ifndef _FCATOMIC_H_
#define _FCATOMIC_H_
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
/* atomic_int */
/* We need external help for these */
#if 0
#elif !defined(FC_NO_MT) && defined(_MSC_VER) || defined(__MINGW32__)
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
/* mingw32 does not have MemoryBarrier.
* MemoryBarrier may be defined as a macro or a function.
* Just make a failsafe version for ourselves. */
#ifdef MemoryBarrier
#define HBMemoryBarrier MemoryBarrier
#else
static inline void HBMemoryBarrier (void) {
long dummy = 0;
InterlockedExchange (&dummy, 1);
}
#endif
typedef long fc_atomic_int_t;
#define fc_atomic_int_add(AI, V) InterlockedExchangeAdd (&(AI), (V))
#define fc_atomic_ptr_get(P) (HBMemoryBarrier (), (void *) *(P))
#define fc_atomic_ptr_cmpexch(P,O,N) (InterlockedCompareExchangePointer ((void **) (P), (void *) (N), (void *) (O)) == (void *) (O))
#elif !defined(FC_NO_MT) && defined(__APPLE__)
#include <libkern/OSAtomic.h>
typedef int32_t fc_atomic_int_t;
#define fc_atomic_int_add(AI, V) (OSAtomicAdd32Barrier ((V), &(AI)) - (V))
#define fc_atomic_ptr_get(P) (OSMemoryBarrier (), (void *) *(P))
#define fc_atomic_ptr_cmpexch(P,O,N) OSAtomicCompareAndSwapPtrBarrier ((void *) (O), (void *) (N), (void **) (P))
#elif !defined(FC_NO_MT) && defined(HAVE_INTEL_ATOMIC_PRIMITIVES)
typedef int fc_atomic_int_t;
#define fc_atomic_int_add(AI, V) __sync_fetch_and_add (&(AI), (V))
#define fc_atomic_ptr_get(P) (void *) (__sync_synchronize (), *(P))
#define fc_atomic_ptr_cmpexch(P,O,N) __sync_bool_compare_and_swap ((P), (O), (N))
#elif !defined(FC_NO_MT)
#define FC_ATOMIC_INT_NIL 1 /* Warn that fallback implementation is in use. */
typedef volatile int fc_atomic_int_t;
#define fc_atomic_int_add(AI, V) (((AI) += (V)) - (V))
#define fc_atomic_ptr_get(P) ((void *) *(P))
#define fc_atomic_ptr_cmpexch(P,O,N) (* (void * volatile *) (P) == (void *) (O) ? (* (void * volatile *) (P) = (void *) (N), true) : false)
#else /* FC_NO_MT */
typedef int fc_atomic_int_t;
#define fc_atomic_int_add(AI, V) (((AI) += (V)) - (V))
#define fc_atomic_ptr_get(P) ((void *) *(P))
#define fc_atomic_ptr_cmpexch(P,O,N) (* (void **) (P) == (void *) (O) ? (* (void **) (P) = (void *) (N), true) : false)
#endif
/* reference count */
#define FC_REF_CONSTANT ((fc_atomic_int_t) -1)
#define FC_REF_CONSTANT_INIT {FC_REF_CONSTANT}
typedef struct _FcRef { fc_atomic_int_t count; } FcRef;
static inline void FcRefInit (FcRef *r, int v) { r->count = v; }
static inline int FcRefInc (FcRef *r) { return fc_atomic_int_add (r->count, +1); }
static inline int FcRefDec (FcRef *r) { return fc_atomic_int_add (r->count, -1); }
static inline void FcRefFinish (FcRef *r) { r->count = FC_REF_CONSTANT; }
static inline FcBool FcRefIsConst (FcRef *r) { return r->count == FC_REF_CONSTANT; }
#endif /* _FCATOMIC_H_ */

View File

@ -44,6 +44,8 @@
#include <fontconfig/fontconfig.h>
#include <fontconfig/fcprivate.h>
#include "fcdeprecate.h"
#include "fcmutex.h"
#include "fcatomic.h"
#ifndef FC_CONFIG_PATH
#define FC_CONFIG_PATH "fonts.conf"
@ -293,8 +295,6 @@ typedef struct _FcCharLeaf {
FcChar32 map[256/32];
} FcCharLeaf;
#define FC_REF_CONSTANT -1
struct _FcCharSet {
int ref; /* reference count */
int num; /* size of leaves and numbers arrays */

126
src/fcmutex.h Normal file
View File

@ -0,0 +1,126 @@
/*
* Atomic int and pointer operations. Originally copied from HarfBuzz.
*
* Copyright © 2007 Chris Wilson
* Copyright © 2009,2010 Red Hat, Inc.
* Copyright © 2011,2012 Google, Inc.
*
* Permission is hereby granted, without written agreement and without
* license or royalty fees, to use, copy, modify, and distribute this
* software and its documentation for any purpose, provided that the
* above copyright notice and the following two paragraphs appear in
* all copies of this software.
*
* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*
* Contributor(s):
* Chris Wilson <chris@chris-wilson.co.uk>
* Red Hat Author(s): Behdad Esfahbod
* Google Author(s): Behdad Esfahbod
*/
#ifndef _FCMUTEX_H_
#define _FCMUTEX_H_
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
/* mutex */
/* We need external help for these */
#if 0
#elif !defined(FC_NO_MT) && defined(_MSC_VER) || defined(__MINGW32__)
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
typedef CRITICAL_SECTION fc_mutex_impl_t;
#define FC_MUTEX_IMPL_INIT { NULL, 0, 0, NULL, NULL, 0 }
#define fc_mutex_impl_init(M) InitializeCriticalSection (M)
#define fc_mutex_impl_lock(M) EnterCriticalSection (M)
#define fc_mutex_impl_unlock(M) LeaveCriticalSection (M)
#define fc_mutex_impl_finish(M) DeleteCriticalSection (M)
#elif !defined(FC_NO_MT) && (defined(HAVE_PTHREAD) || defined(__APPLE__))
#include <pthread.h>
typedef pthread_mutex_t fc_mutex_impl_t;
#define FC_MUTEX_IMPL_INIT PTHREAD_MUTEX_INITIALIZER
#define fc_mutex_impl_init(M) pthread_mutex_init (M, NULL)
#define fc_mutex_impl_lock(M) pthread_mutex_lock (M)
#define fc_mutex_impl_unlock(M) pthread_mutex_unlock (M)
#define fc_mutex_impl_finish(M) pthread_mutex_destroy (M)
#elif !defined(FC_NO_MT) && defined(HAVE_INTEL_ATOMIC_PRIMITIVES)
#if defined(HAVE_SCHED_H) && defined(HAVE_SCHED_YIELD)
# include <sched.h>
# define FC_SCHED_YIELD() sched_yield ()
#else
# define FC_SCHED_YIELD() FC_STMT_START {} FC_STMT_END
#endif
/* This actually is not a totally awful implementation. */
typedef volatile int fc_mutex_impl_t;
#define FC_MUTEX_IMPL_INIT 0
#define fc_mutex_impl_init(M) *(M) = 0
#define fc_mutex_impl_lock(M) FC_STMT_START { while (__sync_lock_test_and_set((M), 1)) FC_SCHED_YIELD (); } FC_STMT_END
#define fc_mutex_impl_unlock(M) __sync_lock_release (M)
#define fc_mutex_impl_finish(M) FC_STMT_START {} FC_STMT_END
#elif !defined(FC_NO_MT)
#if defined(HAVE_SCHED_H) && defined(HAVE_SCHED_YIELD)
# include <sched.h>
# define FC_SCHED_YIELD() sched_yield ()
#else
# define FC_SCHED_YIELD() FC_STMT_START {} FC_STMT_END
#endif
#define FC_MUTEX_INT_NIL 1 /* Warn that fallback implementation is in use. */
typedef volatile int fc_mutex_impl_t;
#define FC_MUTEX_IMPL_INIT 0
#define fc_mutex_impl_init(M) *(M) = 0
#define fc_mutex_impl_lock(M) FC_STMT_START { while (*(M)) FC_SCHED_YIELD (); (*(M))++; } FC_STMT_END
#define fc_mutex_impl_unlock(M) (*(M))--;
#define fc_mutex_impl_finish(M) FC_STMT_START {} FC_STMT_END
#else /* FC_NO_MT */
typedef int fc_mutex_impl_t;
#define FC_MUTEX_IMPL_INIT 0
#define fc_mutex_impl_init(M) FC_STMT_START {} FC_STMT_END
#define fc_mutex_impl_lock(M) FC_STMT_START {} FC_STMT_END
#define fc_mutex_impl_unlock(M) FC_STMT_START {} FC_STMT_END
#define fc_mutex_impl_finish(M) FC_STMT_START {} FC_STMT_END
#endif
#define FC_MUTEX_INIT {FC_MUTEX_IMPL_INIT}
typedef fc_mutex_impl_t FcMutex;
static inline void FcMutexInit (FcMutex *m) { fc_mutex_impl_init (m); }
static inline void FcMutexLock (FcMutex *m) { fc_mutex_impl_lock (m); }
static inline void FcMutexUnlock (FcMutex *m) { fc_mutex_impl_unlock (m); }
static inline void FcMutexFinish (FcMutex *m) { fc_mutex_impl_finish (m); }
#endif /* _FCMUTEX_H_ */