1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/security/nss/lib/ssl/sslmutex.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,125 @@
1.4 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.5 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.6 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.7 +#ifndef __SSLMUTEX_H_
1.8 +#define __SSLMUTEX_H_ 1
1.9 +
1.10 +/* What SSL really wants is portable process-shared unnamed mutexes in
1.11 + * shared memory, that have the property that if the process that holds
1.12 + * them dies, they are released automatically, and that (unlike fcntl
1.13 + * record locking) lock to the thread, not to the process.
1.14 + * NSPR doesn't provide that.
1.15 + * Windows has mutexes that meet that description, but they're not portable.
1.16 + * POSIX mutexes are not automatically released when the holder dies,
1.17 + * and other processes/threads cannot release the mutex on behalf of the
1.18 + * dead holder.
1.19 + * POSIX semaphores can be used to accomplish this on systems that implement
1.20 + * process-shared unnamed POSIX semaphores, because a watchdog thread can
1.21 + * discover and release semaphores that were held by a dead process.
1.22 + * On systems that do not support process-shared POSIX unnamed semaphores,
1.23 + * they can be emulated using pipes.
1.24 + * The performance cost of doing that is not yet measured.
1.25 + *
1.26 + * So, this API looks a lot like POSIX pthread mutexes.
1.27 + */
1.28 +
1.29 +#include "prtypes.h"
1.30 +#include "prlock.h"
1.31 +
1.32 +#if defined(NETBSD)
1.33 +#include <sys/param.h> /* for __NetBSD_Version__ */
1.34 +#endif
1.35 +
1.36 +#if defined(WIN32)
1.37 +
1.38 +#include <wtypes.h>
1.39 +
1.40 +typedef struct
1.41 +{
1.42 + PRBool isMultiProcess;
1.43 +#ifdef WINNT
1.44 + /* on WINNT we need both the PRLock and the Win32 mutex for fibers */
1.45 + struct {
1.46 +#else
1.47 + union {
1.48 +#endif
1.49 + PRLock* sslLock;
1.50 + HANDLE sslMutx;
1.51 + } u;
1.52 +} sslMutex;
1.53 +
1.54 +typedef int sslPID;
1.55 +
1.56 +#elif defined(LINUX) || defined(AIX) || defined(BEOS) || defined(BSDI) || (defined(NETBSD) && __NetBSD_Version__ < 500000000) || defined(OPENBSD)
1.57 +
1.58 +#include <sys/types.h>
1.59 +#include "prtypes.h"
1.60 +
1.61 +typedef struct {
1.62 + PRBool isMultiProcess;
1.63 + union {
1.64 + PRLock* sslLock;
1.65 + struct {
1.66 + int mPipes[3];
1.67 + PRInt32 nWaiters;
1.68 + } pipeStr;
1.69 + } u;
1.70 +} sslMutex;
1.71 +typedef pid_t sslPID;
1.72 +
1.73 +#elif defined(XP_UNIX) /* other types of Unix */
1.74 +
1.75 +#include <sys/types.h> /* for pid_t */
1.76 +#include <semaphore.h> /* for sem_t, and sem_* functions */
1.77 +
1.78 +typedef struct
1.79 +{
1.80 + PRBool isMultiProcess;
1.81 + union {
1.82 + PRLock* sslLock;
1.83 + sem_t sem;
1.84 + } u;
1.85 +} sslMutex;
1.86 +
1.87 +typedef pid_t sslPID;
1.88 +
1.89 +#else
1.90 +
1.91 +/* what platform is this ?? */
1.92 +
1.93 +typedef struct {
1.94 + PRBool isMultiProcess;
1.95 + union {
1.96 + PRLock* sslLock;
1.97 + /* include cross-process locking mechanism here */
1.98 + } u;
1.99 +} sslMutex;
1.100 +
1.101 +typedef int sslPID;
1.102 +
1.103 +#endif
1.104 +
1.105 +#include "seccomon.h"
1.106 +
1.107 +SEC_BEGIN_PROTOS
1.108 +
1.109 +extern SECStatus sslMutex_Init(sslMutex *sem, int shared);
1.110 +
1.111 +/* If processLocal is set to true, then just free resources which are *only* associated
1.112 + * with the current process. Leave any shared resources (including the state of
1.113 + * shared memory) intact. */
1.114 +extern SECStatus sslMutex_Destroy(sslMutex *sem, PRBool processLocal);
1.115 +
1.116 +extern SECStatus sslMutex_Unlock(sslMutex *sem);
1.117 +
1.118 +extern SECStatus sslMutex_Lock(sslMutex *sem);
1.119 +
1.120 +#ifdef WINNT
1.121 +
1.122 +extern SECStatus sslMutex_2LevelInit(sslMutex *sem);
1.123 +
1.124 +#endif
1.125 +
1.126 +SEC_END_PROTOS
1.127 +
1.128 +#endif
