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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef __SSLMUTEX_H_
#define __SSLMUTEX_H_ 1
/* What SSL really wants is portable process-shared unnamed mutexes in
* shared memory, that have the property that if the process that holds
* them dies, they are released automatically, and that (unlike fcntl
* record locking) lock to the thread, not to the process.
* NSPR doesn't provide that.
* Windows has mutexes that meet that description, but they're not portable.
* POSIX mutexes are not automatically released when the holder dies,
* and other processes/threads cannot release the mutex on behalf of the
* dead holder.
* POSIX semaphores can be used to accomplish this on systems that implement
* process-shared unnamed POSIX semaphores, because a watchdog thread can
* discover and release semaphores that were held by a dead process.
* On systems that do not support process-shared POSIX unnamed semaphores,
* they can be emulated using pipes.
* The performance cost of doing that is not yet measured.
*
* So, this API looks a lot like POSIX pthread mutexes.
*/
#include "prtypes.h"
#include "prlock.h"
#if defined(NETBSD)
#include <sys/param.h> /* for __NetBSD_Version__ */
#endif
#if defined(WIN32)
#include <wtypes.h>
typedef struct {
PRBool isMultiProcess;
#ifdef WINNT
/* on WINNT we need both the PRLock and the Win32 mutex for fibers */
struct {
#else
union {
#endif
PRLock *sslLock;
HANDLE sslMutx;
} u;
} sslMutex;
typedef int sslPID;
#elif defined(LINUX) || defined(AIX) || defined(BSDI) || \
(defined(NETBSD) && __NetBSD_Version__ < 500000000) || defined(OPENBSD) || defined(__GLIBC__)
#include <sys/types.h>
#include "prtypes.h"
typedef struct {
PRBool isMultiProcess;
union {
PRLock *sslLock;
struct {
int mPipes[3];
PRInt32 nWaiters;
} pipeStr;
} u;
} sslMutex;
typedef pid_t sslPID;
/* other types of unix, except OS X */
#elif defined(XP_UNIX) && !defined(DARWIN)
#include <sys/types.h> /* for pid_t */
#include <semaphore.h> /* for sem_t, and sem_* functions */
typedef struct {
PRBool isMultiProcess;
union {
PRLock *sslLock;
sem_t sem;
} u;
} sslMutex;
typedef pid_t sslPID;
#else /* no support for cross-process locking */
/* what platform is this ?? */
typedef struct {
PRBool isMultiProcess;
union {
PRLock *sslLock;
/* include cross-process locking mechanism here */
} u;
} sslMutex;
#ifdef DARWIN
typedef pid_t sslPID;
#else
typedef int sslPID;
#endif
#endif
#include "seccomon.h"
SEC_BEGIN_PROTOS
extern SECStatus sslMutex_Init(sslMutex *sem, int shared);
/* If processLocal is set to true, then just free resources which are *only* associated
* with the current process. Leave any shared resources (including the state of
* shared memory) intact. */
extern SECStatus sslMutex_Destroy(sslMutex *sem, PRBool processLocal);
extern SECStatus sslMutex_Unlock(sslMutex *sem);
extern SECStatus sslMutex_Lock(sslMutex *sem);
#ifdef WINNT
extern SECStatus sslMutex_2LevelInit(sslMutex *sem);
#endif
SEC_END_PROTOS
#endif