mpm_winnt.c

Apache V2.0.15 Alpha For Linuxhttpd-2_0_15-alpha.tar.Z

/* ====================================================================
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 2000-2001 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.
 *
 * 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.
 *
 * 4. The names "Apache" and "Apache Software Foundation" must
 *    not be used to endorse or promote products derived from this
 *    software without prior written permission. For written
 *    permission, please contact [e-mail].
 *
 * 5. Products derived from this software may not be called "Apache",
 *    nor may "Apache" appear in their name, without prior written
 *    permission of the Apache Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 * Portions of this software are based upon public domain software
 * originally written at the National Center for Supercomputing Applications,
 * University of Illinois, Urbana-Champaign.
 */

#define CORE_PRIVATE 
#include "httpd.h" 
#include "http_main.h" 
#include "http_log.h" 
#include "http_config.h"	/* for read_config */ 
#include "http_core.h"		/* for get_remote_host */ 
#include "http_connection.h"
#include "apr_portable.h"
#include "apr_getopt.h"
#include "apr_strings.h"
#include "apr_lib.h"
#include "ap_mpm.h"
#include "ap_config.h"
#include "ap_listen.h"
#include "mpm_default.h"
#include "mpm_winnt.h"
#include "mpm_common.h"
#include "scoreboard.h"


typedef HANDLE thread;
#ifdef CONTAINING_RECORD
#undef CONTAINING_RECORD
#endif
#define CONTAINING_RECORD(address, type, field) ((type *)( \
                                                  (PCHAR)(address) - \
                                                  (PCHAR)(&((type *)0)->field)))
#define PADDED_ADDR_SIZE sizeof(SOCKADDR_IN)+16

typedef struct CompContext {
    struct CompContext *next;
    OVERLAPPED Overlapped;
    apr_socket_t *sock;
    SOCKET accept_socket;
    char buff[2*PADDED_ADDR_SIZE];
    struct sockaddr *sa_server;
    int sa_server_len;
    struct sockaddr *sa_client;
    int sa_client_len;
    apr_pool_t *ptrans;
} COMP_CONTEXT, *PCOMP_CONTEXT;

typedef enum {
    IOCP_CONNECTION_ACCEPTED = 1,
    IOCP_WAIT_FOR_RECEIVE = 2,
    IOCP_WAIT_FOR_TRANSMITFILE = 3,
    IOCP_SHUTDOWN = 4
} io_state_e;

/* Queue for managing the passing of COMP_CONTEXTs from 
 * the accept thread to the worker threads and back again
 */
apr_lock_t  *qlock;
COMP_CONTEXT *qhead = NULL;
COMP_CONTEXT *qtail = NULL;

static HANDLE ThreadDispatchIOCP = NULL;

/* Definitions of WINNT MPM specific config globals */
static server_rec *server_conf;
static apr_pool_t *pconf;
static apr_pool_t *pchild = NULL;
static int workers_may_exit = 0;
static int shutdown_in_progress = 0;
static unsigned int g_blocked_threads = 0;
static int ap_max_requests_per_child=0;

static char *ap_pid_fname = NULL;

static HANDLE shutdown_event;	/* used to signal the parent to shutdown */
static HANDLE restart_event;	/* used to signal the parent to restart */
static HANDLE exit_event;       /* used by parent to signal the child to exit */
static HANDLE maintenance_event;

static char ap_coredump_dir[MAX_STRING_LEN];

static int one_process = 0;
static char const* signal_arg;

OSVERSIONINFO osver; /* VER_PLATFORM_WIN32_NT */

apr_lock_t *start_mutex;
static DWORD my_pid;
static DWORD parent_pid;

int ap_threads_per_child = 0;
int ap_daemons_to_start=0;

/* ap_get_max_daemons and ap_my_generation are used by the scoreboard
 * code
 */
ap_generation_t volatile ap_my_generation=0; /* Used by the scoreboard */

/* This is the helper code to resolve late bound entry points 
 * missing from one or more releases of the Win32 API...
 * but it sure would be nice if we didn't duplicate this code
 * from the APR ;-)
 */
static const char* const lateDllName[DLL_defined] = {
    "kernel32", "advapi32", "mswsock",  "ws2_32"  };
static HMODULE lateDllHandle[DLL_defined] = {
    NULL,       NULL,       NULL,       NULL      };

FARPROC ap_load_dll_func(ap_dlltoken_e fnLib, char* fnName, int ordinal)
{
    if (!lateDllHandle[fnLib]) { 
        lateDllHandle[fnLib] = LoadLibrary(lateDllName[fnLib]);
        if (!lateDllHandle[fnLib])
            return NULL;
    }
    if (ordinal)
        return GetProcAddress(lateDllHandle[fnLib], (char *) ordinal);
    else
        return GetProcAddress(lateDllHandle[fnLib], fnName);
}

/* To share the semaphores with other processes, we need a NULL ACL
 * Code from MS KB Q106387
 */
static PSECURITY_ATTRIBUTES GetNullACL()
{
    PSECURITY_DESCRIPTOR pSD;
    PSECURITY_ATTRIBUTES sa;

    sa  = (PSECURITY_ATTRIBUTES) LocalAlloc(LPTR, sizeof(SECURITY_ATTRIBUTES));
    pSD = (PSECURITY_DESCRIPTOR) LocalAlloc(LPTR,
					    SECURITY_DESCRIPTOR_MIN_LENGTH);
    if (pSD == NULL || sa == NULL) {
        return NULL;
    }
    apr_set_os_error(0);
    if (!InitializeSecurityDescriptor(pSD, SECURITY_DESCRIPTOR_REVISION)
	|| apr_get_os_error()) {
        LocalFree( pSD );
        LocalFree( sa );
        return NULL;
    }
    if (!SetSecurityDescriptorDacl(pSD, TRUE, (PACL) NULL, FALSE)
	|| apr_get_os_error()) {
        LocalFree( pSD );
        LocalFree( sa );
        return NULL;
    }
    sa->nLength = sizeof(sa);
    sa->lpSecurityDescriptor = pSD;
    sa->bInheritHandle = TRUE;
    return sa;
}

static void CleanNullACL( void *sa ) {
    if( sa ) {
        LocalFree( ((PSECURITY_ATTRIBUTES)sa)->lpSecurityDescriptor);
        LocalFree( sa );
    }
}

/*
 * The Win32 call WaitForMultipleObjects will only allow you to wait for 
 * a maximum of MAXIMUM_WAIT_OBJECTS (current 64).  Since the threading 
 * model in the multithreaded version of apache wants to use this call, 
 * we are restricted to a maximum of 64 threads.  This is a simplistic 
 * routine that will increase this size.
 */
static DWORD wait_for_many_objects(DWORD nCount, CONST HANDLE *lpHandles, 
                                   DWORD dwSeconds)
{
    time_t tStopTime;
    DWORD dwRet = WAIT_TIMEOUT;
    DWORD dwIndex=0;
    BOOL bFirst = TRUE;
  
    tStopTime = time(NULL) + dwSeconds;
  
    do {
        if (!bFirst)
            Sleep(1000);
        else
            bFirst = FALSE;
          
        for (dwIndex = 0; dwIndex * MAXIMUM_WAIT_OBJECTS < nCount; dwIndex++) {
            dwRet = WaitForMultipleObjects( 
                min(MAXIMUM_WAIT_OBJECTS, nCount - (dwIndex * MAXIMUM_WAIT_OBJECTS)),
                lpHandles + (dwIndex * MAXIMUM_WAIT_OBJECTS), 
                0, 0);
                                           
            if (dwRet != WAIT_TIMEOUT) {                                          
              break;
            }
        }
    } while((time(NULL) < tStopTime) && (dwRet == WAIT_TIMEOUT));
    
    return dwRet;
}

/*
 * Signalling Apache on NT.
 *
 * Under Unix, Apache can be told to shutdown or restart by sending various
 * signals (HUP, USR, TERM). On NT we don't have easy access to signals, so
 * we use "events" instead. The parent apache process goes into a loop
 * where it waits forever for a set of events. Two of those events are
 * called
 *
 *    apPID_shutdown
 *    apPID_restart
 *
 * (where PID is the PID of the apache parent process). When one of these
 * is signalled, the Apache parent performs the appropriate action. The events
 * can become signalled through internal Apache methods (e.g. if the child
 * finds a fatal error and needs to kill its parent), via the service
 * control manager (the control thread will signal the shutdown event when
 * requested to stop the Apache service), from the -k Apache command line,
 * or from any external program which finds the Apache PID from the
 * httpd.pid file.
 *
 * The signal_parent() function, below, is used to signal one of these events.
 * It can be called by any child or parent process, since it does not
 * rely on global variables.
 *
 * On entry, type gives the event to signal. 0 means shutdown, 1 means 
 * graceful restart.
 */
/*
 * Initialise the signal names, in the global variables signal_name_prefix, 
 * signal_restart_name and signal_shutdown_name.
 */
#define MAX_SIGNAL_NAME 30  /* Long enough for apPID_shutdown, where PID is an int */
char signal_name_prefix[MAX_SIGNAL_NAME];
char signal_restart_name[MAX_SIGNAL_NAME]; 
char signal_shutdown_name[MAX_SIGNAL_NAME];
void setup_signal_names(char *prefix)
{
    apr_snprintf(signal_name_prefix, sizeof(signal_name_prefix), prefix);    
    apr_snprintf(signal_shutdown_name, sizeof(signal_shutdown_name), 
	"%s_shutdown", signal_name_prefix);    
    apr_snprintf(signal_restart_name, sizeof(signal_restart_name), 
	"%s_restart", signal_name_prefix);    
}

void signal_parent(int type)
{
    HANDLE e;
    char *signal_name;
    
    /* after updating the shutdown_pending or restart flags, we need
     * to wake up the parent process so it can see the changes. The
     * parent will normally be waiting for either a child process
     * to die, or for a signal on the "spache-signal" event. So set the
     * "apache-signal" event here.
     */
    if (one_process) {
	return;
    }

    switch(type) {
    case 0: signal_name = signal_shutdown_name; break;
    case 1: signal_name = signal_restart_name; break;
    default: return;
    }
    e = OpenEvent(EVENT_ALL_ACCESS, FALSE, signal_name);
    if (!e) {
	/* Um, problem, can't signal the parent, which means we can't
	 * signal ourselves to die. Ignore for now...
	 */
	ap_log_error(APLOG_MARK, APLOG_EMERG, apr_get_os_error(), server_conf,
                     "OpenEvent on %s event", signal_name);
	return;
    }
    if (SetEvent(e) == 0) {
	/* Same problem as above */
	ap_log_error(APLOG_MARK, APLOG_EMERG, apr_get_os_error(), server_conf,
                     "SetEvent on %s event", signal_name);
	CloseHandle(e);
	return;
    }
    CloseHandle(e);
}

static int volatile is_graceful = 0;

AP_DECLARE(int) ap_graceful_stop_signalled(void)
{
    return is_graceful;
}

AP_DECLARE(void) ap_start_shutdown(void)
{
    signal_parent(0);
}

AP_DECLARE(void) ap_start_restart(int gracefully)
{
    is_graceful = gracefully;
    signal_parent(1);
}


/*
 * find_ready_listener()
 * Only used by Win9* and should go away when the win9*_accept() function is 
 * reimplemented using apr_poll().
 */
static ap_listen_rec *head_listener;
static APR_INLINE ap_listen_rec *find_ready_listener(fd_set * main_fds)
{
    ap_listen_rec *lr;
    SOCKET nsd;

    for (lr = head_listener; lr ; lr = lr->next) {
        apr_os_sock_get(&nsd, lr->sd);
	if (FD_ISSET(nsd, main_fds)) {
	    head_listener = lr->next;