Home | History | Annotate | Download | only in ssl 
      1 /* ***** BEGIN LICENSE BLOCK *****
      2  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
      3  *
      4  * The contents of this file are subject to the Mozilla Public License Version
      5  * 1.1 (the "License"); you may not use this file except in compliance with
      6  * the License. You may obtain a copy of the License at
      7  * http://www.mozilla.org/MPL/
      8  *
      9  * Software distributed under the License is distributed on an "AS IS" basis,
     10  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
     11  * for the specific language governing rights and limitations under the
     12  * License.
     13  *
     14  * The Original Code is the Netscape security libraries.
     15  *
     16  * The Initial Developer of the Original Code is
     17  * Netscape Communications Corporation.
     18  * Portions created by the Initial Developer are Copyright (C) 2001
     19  * the Initial Developer. All Rights Reserved.
     20  *
     21  * Contributor(s):
     22  *
     23  * Alternatively, the contents of this file may be used under the terms of
     24  * either the GNU General Public License Version 2 or later (the "GPL"), or
     25  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
     26  * in which case the provisions of the GPL or the LGPL are applicable instead
     27  * of those above. If you wish to allow use of your version of this file only
     28  * under the terms of either the GPL or the LGPL, and not to allow others to
     29  * use your version of this file under the terms of the MPL, indicate your
     30  * decision by deleting the provisions above and replace them with the notice
     31  * and other provisions required by the GPL or the LGPL. If you do not delete
     32  * the provisions above, a recipient may use your version of this file under
     33  * the terms of any one of the MPL, the GPL or the LGPL.
     34  *
     35  * ***** END LICENSE BLOCK ***** */
     36 /* $Id: sslmutex.h,v 1.12 2009/06/05 02:34:15 nelson%bolyard.com Exp $ */
     37 #ifndef __SSLMUTEX_H_
     38 #define __SSLMUTEX_H_ 1
     39 
     40 /* What SSL really wants is portable process-shared unnamed mutexes in
     41  * shared memory, that have the property that if the process that holds
     42  * them dies, they are released automatically, and that (unlike fcntl
     43  * record locking) lock to the thread, not to the process.
     44  * NSPR doesn't provide that.
     45  * Windows has mutexes that meet that description, but they're not portable.
     46  * POSIX mutexes are not automatically released when the holder dies,
     47  * and other processes/threads cannot release the mutex on behalf of the
     48  * dead holder.
     49  * POSIX semaphores can be used to accomplish this on systems that implement
     50  * process-shared unnamed POSIX semaphores, because a watchdog thread can
     51  * discover and release semaphores that were held by a dead process.
     52  * On systems that do not support process-shared POSIX unnamed semaphores,
     53  * they can be emulated using pipes.
     54  * The performance cost of doing that is not yet measured.
     55  *
     56  * So, this API looks a lot like POSIX pthread mutexes.
     57  */
     58 
     59 #include "prtypes.h"
     60 #include "prlock.h"
     61 
     62 #if defined(NETBSD)
     63 #include <sys/param.h> /* for __NetBSD_Version__ */
     64 #endif
     65 
     66 #if defined(WIN32)
     67 
     68 #include <wtypes.h>
     69 
     70 typedef struct
     71 {
     72     PRBool isMultiProcess;
     73 #ifdef WINNT
     74     /* on WINNT we need both the PRLock and the Win32 mutex for fibers */
     75     struct {
     76 #else
     77     union {
     78 #endif
     79         PRLock* sslLock;
     80         HANDLE sslMutx;
     81     } u;
     82 } sslMutex;
     83 
     84 typedef int    sslPID;
     85 
     86 #elif defined(LINUX) || defined(AIX) || defined(BEOS) || defined(BSDI) || (defined(NETBSD) && __NetBSD_Version__ < 500000000) || defined(OPENBSD)
     87 
     88 #include <sys/types.h>
     89 #include "prtypes.h"
     90 
     91 typedef struct {
     92     PRBool isMultiProcess;
     93     union {
     94         PRLock* sslLock;
     95         struct {
     96             int      mPipes[3];
     97             PRInt32  nWaiters;
     98         } pipeStr;
     99     } u;
    100 } sslMutex;
    101 typedef pid_t sslPID;
    102 
    103 #elif defined(XP_UNIX) /* other types of Unix */
    104 
    105 #include <sys/types.h>	/* for pid_t */
    106 #include <semaphore.h>  /* for sem_t, and sem_* functions */
    107 
    108 typedef struct
    109 {
    110     PRBool isMultiProcess;
    111     union {
    112         PRLock* sslLock;
    113         sem_t  sem;
    114     } u;
    115 } sslMutex;
    116 
    117 typedef pid_t sslPID;
    118 
    119 #else
    120 
    121 /* what platform is this ?? */
    122 
    123 typedef struct {
    124     PRBool isMultiProcess;
    125     union {
    126         PRLock* sslLock;
    127         /* include cross-process locking mechanism here */
    128     } u;
    129 } sslMutex;
    130 
    131 typedef int sslPID;
    132 
    133 #endif
    134 
    135 #include "seccomon.h"
    136 
    137 SEC_BEGIN_PROTOS
    138 
    139 extern SECStatus sslMutex_Init(sslMutex *sem, int shared);
    140 
    141 extern SECStatus sslMutex_Destroy(sslMutex *sem);
    142 
    143 extern SECStatus sslMutex_Unlock(sslMutex *sem);
    144 
    145 extern SECStatus sslMutex_Lock(sslMutex *sem);
    146 
    147 #ifdef WINNT
    148 
    149 extern SECStatus sslMutex_2LevelInit(sslMutex *sem);
    150 
    151 #endif
    152 
    153 SEC_END_PROTOS
    154 
    155 #endif
    156