modules/ssl/ssl_engine_mutex.c

/*                      _             _
**  _ __ ___   ___   __| |    ___ ___| |  mod_ssl
** | '_ ` _ \ / _ \ / _` |   / __/ __| |  Apache Interface to OpenSSL
** | | | | | | (_) | (_| |   \__ \__ \ |  www.modssl.org
** |_| |_| |_|\___/ \__,_|___|___/___/_|  ftp.modssl.org
**                      |_____|
**  ssl_engine_mutex.c
**  Semaphore for Mutual Exclusion
*/

/* ====================================================================
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 2000-2002 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
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 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
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                             /* ``Real programmers confuse
                                  Christmas and Halloween
                                  because DEC 25 = OCT 31.''
                                             -- Unknown     */
#include "mod_ssl.h"

int ssl_mutex_init(server_rec *s, apr_pool_t *p)
{
    SSLModConfigRec *mc = myModConfig(s);

    if (mc->nMutexMode == SSL_MUTEXMODE_NONE) 
        return TRUE;

    if (apr_lock_create(&mc->pMutex, APR_MUTEX, APR_LOCKALL, APR_LOCK_DEFAULT,
                        mc->szMutexFile, p) != APR_SUCCESS) {
        ssl_log(s, SSL_LOG_ERROR,
                   "Cannot create SSLMutex file `%s'",
                    mc->szMutexFile);
        return FALSE;
    }
    return TRUE;
}

int ssl_mutex_reinit(server_rec *s, apr_pool_t *p)
{
    SSLModConfigRec *mc = myModConfig(s);

    if (mc->nMutexMode == SSL_MUTEXMODE_NONE)
        return TRUE;

    if (apr_lock_child_init(&mc->pMutex, mc->szMutexFile, p) != APR_SUCCESS)
        return FALSE;
    return TRUE;
}

int ssl_mutex_on(server_rec *s)
{
    SSLModConfigRec *mc = myModConfig(s);

    if (mc->nMutexMode == SSL_MUTEXMODE_NONE)
        return TRUE;
    if (apr_lock_acquire(mc->pMutex) != APR_SUCCESS) {
        ssl_log(s, SSL_LOG_WARN, "Failed to acquire global mutex lock");
        return FALSE;
    }
    return TRUE;
}

int ssl_mutex_off(server_rec *s)
{
    SSLModConfigRec *mc = myModConfig(s);

    if (mc->nMutexMode == SSL_MUTEXMODE_NONE)
        return TRUE;
    if (apr_lock_release(mc->pMutex) != APR_SUCCESS) {
        ssl_log(s, SSL_LOG_WARN, "Failed to release global mutex lock");
        return FALSE;
    }
    return TRUE;
}