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Posted to cvs@httpd.apache.org by ma...@hyperreal.org on 1999/07/21 21:07:12 UTC

cvs commit: apache-2.0/mpm/src/modules/mpm/dexter Makefile.libdir Makefile.tmpl acceptlock.c acceptlock.h dexter.c dexter.h mpm_default.h scoreboard.c scoreboard.h

manoj       99/07/21 12:07:11

  Added:       mpm/src/modules/mpm/dexter Makefile.libdir Makefile.tmpl
                        acceptlock.c acceptlock.h dexter.c dexter.h
                        mpm_default.h scoreboard.c scoreboard.h
  Log:
  A new experimental MPM. Right now, it is the mpmt_pthread MPM with idle
  process management taken out (so the number of processes is constant)
  and with the scoreboard eliminated (replaced with a little table seen
  only by the parent). This will be a testbed for playing around with
  thread pools.
  
  Revision  Changes    Path
  1.1                  apache-2.0/mpm/src/modules/mpm/dexter/Makefile.libdir
  
  Index: Makefile.libdir
  ===================================================================
  This is a place-holder which indicates to Configure that it shouldn't
  provide the default targets when building the Makefile in this directory.
  Instead it'll just prepend all the important variable definitions, and
  copy the Makefile.tmpl onto the end.
  
  
  
  1.1                  apache-2.0/mpm/src/modules/mpm/dexter/Makefile.tmpl
  
  Index: Makefile.tmpl
  ===================================================================
  
  LIB=libdexter.$(LIBEXT)
  
  OBJS=\
       dexter.o acceptlock.o scoreboard.o
  OBJS_PIC=\
       dexter.lo acceptlock.lo scoreboard.lo
  
  all: lib
  
  lib: $(LIB)
  
  libdexter.a: $(OBJS)
  	rm -f $@
  	ar cr $@ $(OBJS)
  	$(RANLIB) $@
  
  libdexter.so: $(OBJS_PIC)
  	rm -f $@
  	$(LD_SHLIB) $(LDFLAGS_SHLIB) -o $@ $(OBJS_PIC) $(LIBS_SHLIB)
  
  libdexter.dll: $(OBJS_PIC) dexter.def
  	$(LD_SHLIB) $(LDFLAGS_SHLIB) -o $* $(OBJS_PIC) $(LIBS_SHLIB)
  	emxbind -b -q -s -h0 -ddexter.def $* && \
  	rm $*
  
  .SUFFIXES: .o .lo .dll
  
  .c.o:
  	$(CC) -c $(INCLUDES) $(CFLAGS) $<
  
  .c.lo:
  	$(CC) -c $(INCLUDES) $(CFLAGS) $(CFLAGS_SHLIB) $< && mv $*.o $*.lo
  
  clean:
  	rm -f $(OBJS) $(OBJS_PIC) $(LIB)
  
  distclean: clean
  	-rm -f Makefile
  
  # We really don't expect end users to use this rule.  It works only with
  # gcc, and rebuilds Makefile.tmpl.  You have to re-run Configure after
  # using it.
  depend:
  	cp Makefile.tmpl Makefile.tmpl.bak \
  	    && sed -ne '1,/^# DO NOT REMOVE/p' Makefile.tmpl > Makefile.new \
  	    && gcc -MM $(INCLUDES) $(CFLAGS) *.c >> Makefile.new \
  	    && sed -e '1,$$s: $(INCDIR)/: $$(INCDIR)/:g' \
  	           -e '1,$$s: $(OSDIR)/: $$(OSDIR)/:g' Makefile.new \
  		> Makefile.tmpl \
  	    && rm Makefile.new
  
  #Dependencies
  
  $(OBJS) $(OBJS_PIC): Makefile
  
  # DO NOT REMOVE
  acceptlock.o: acceptlock.c $(INCDIR)/httpd.h \
   $(INCDIR)/ap_config.h $(INCDIR)/ap_mmn.h \
   $(INCDIR)/ap_config_auto.h $(OSDIR)/os.h \
   $(OSDIR)/os-inline.c $(INCDIR)/ap_ctype.h \
   $(INCDIR)/hsregex.h $(INCDIR)/alloc.h \
   $(INCDIR)/buff.h $(INCDIR)/ap_iol.h \
   $(INCDIR)/ap.h $(INCDIR)/apr.h \
   $(INCDIR)/util_uri.h $(INCDIR)/http_main.h \
   $(INCDIR)/http_log.h $(INCDIR)/http_config.h \
   $(INCDIR)/ap_hooks.h $(INCDIR)/http_protocol.h \
   $(INCDIR)/http_request.h $(INCDIR)/http_conf_globals.h \
   $(INCDIR)/http_core.h $(INCDIR)/http_vhost.h \
   $(INCDIR)/util_script.h acceptlock.h dexter.h \
   $(OSDIR)/unixd.h
  dexter.o: dexter.c $(INCDIR)/httpd.h \
   $(INCDIR)/ap_config.h $(INCDIR)/ap_mmn.h \
   $(INCDIR)/ap_config_auto.h $(OSDIR)/os.h \
   $(OSDIR)/os-inline.c $(INCDIR)/ap_ctype.h \
   $(INCDIR)/hsregex.h $(INCDIR)/alloc.h \
   $(INCDIR)/buff.h $(INCDIR)/ap_iol.h \
   $(INCDIR)/ap.h $(INCDIR)/apr.h \
   $(INCDIR)/util_uri.h $(INCDIR)/http_main.h \
   $(INCDIR)/http_log.h $(INCDIR)/http_config.h \
   $(INCDIR)/ap_hooks.h $(INCDIR)/http_core.h \
   $(INCDIR)/http_connection.h $(INCDIR)/ap_mpm.h \
   $(OSDIR)/unixd.h $(OSDIR)/iol_socket.h \
   $(INCDIR)/ap_listen.h scoreboard.h mpm_default.h acceptlock.h
  scoreboard.o: scoreboard.c $(INCDIR)/httpd.h \
   $(INCDIR)/ap_config.h $(INCDIR)/ap_mmn.h \
   $(INCDIR)/ap_config_auto.h $(OSDIR)/os.h \
   $(OSDIR)/os-inline.c $(INCDIR)/ap_ctype.h \
   $(INCDIR)/hsregex.h $(INCDIR)/alloc.h \
   $(INCDIR)/buff.h $(INCDIR)/ap_iol.h \
   $(INCDIR)/ap.h $(INCDIR)/apr.h \
   $(INCDIR)/util_uri.h $(INCDIR)/http_log.h \
   $(INCDIR)/http_main.h $(INCDIR)/http_core.h \
   $(INCDIR)/http_config.h $(INCDIR)/ap_hooks.h \
   $(OSDIR)/unixd.h $(INCDIR)/http_conf_globals.h \
   dexter.h scoreboard.h mpm_default.h
  
  
  
  1.1                  apache-2.0/mpm/src/modules/mpm/dexter/acceptlock.c
  
  Index: acceptlock.c
  ===================================================================
  /* ====================================================================
   * Copyright (c) 1995-1999 The Apache Group.  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. All advertising materials mentioning features or use of this 
   *    software must display the following acknowledgment: 
   *    "This product includes software developed by the Apache Group 
   *    for use in the Apache HTTP server project (http://www.apache.org/)." 
   * 
   * 4. The names "Apache Server" and "Apache Group" must not be used to 
   *    endorse or promote products derived from this software without 
   *    prior written permission. For written permission, please contact 
   *    apache@apache.org. 
   * 
   * 5. Products derived from this software may not be called "Apache" 
   *    nor may "Apache" appear in their names without prior written 
   *    permission of the Apache Group. 
   * 
   * 6. Redistributions of any form whatsoever must retain the following 
   *    acknowledgment: 
   *    "This product includes software developed by the Apache Group 
   *    for use in the Apache HTTP server project (http://www.apache.org/)." 
   * 
   * THIS SOFTWARE IS PROVIDED BY THE APACHE GROUP ``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 GROUP 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 Group and was originally based 
   * on public domain software written at the National Center for 
   * Supercomputing Applications, University of Illinois, Urbana-Champaign. 
   * For more information on the Apache Group and the Apache HTTP server 
   * project, please see <http://www.apache.org/>. 
   * 
   */ 
  
  #include "httpd.h" 
  #include "http_main.h" 
  #include "http_log.h" 
  #include "http_config.h"	/* for read_config */ 
  #include "http_protocol.h"	/* for read_request */ 
  #include "http_request.h"	/* for process_request */ 
  #include "http_conf_globals.h" 
  #include "http_core.h"		/* for get_remote_host */ 
  #include "http_vhost.h" 
  #include "util_script.h"	/* to force util_script.c linking */ 
  #include "util_uri.h" 
  #include "acceptlock.h"
  #include "dexter.h"	/* For clean_child_exit */
  #include "unixd.h"
  #include <netinet/tcp.h> 
  #include <stdio.h> 
  
  #ifdef USE_SHMGET_SCOREBOARD
  #include <sys/types.h>
  #include <sys/ipc.h>
  #include <sys/shm.h>
  #endif
   
  #include <pthread.h>
  
  /* TODO: all these calls have to be ap_ prefixed, right? */
  /* Number of cross-process locks we're managing */
  static int lock_count;
  
  /* Filename prefix for locks */
  char *ap_lock_fname;
  
  /* Number of intra-process locks we're managing */
  static int intra_lock_count;
  
  /* Intraprocess locking used by other serialization techniques */
  static pthread_mutex_t *intra_mutex = NULL;
  
  static void intra_mutex_cleanup(void *foo)
  {
      int i;
  
      for (i = 0; i < intra_lock_count; i++) {
          (void) pthread_mutex_destroy(&intra_mutex[i]);
      }
  }
  
  void intra_mutex_init(pool *p, int number_of_locks)
  {
      int i;
  
      intra_lock_count = number_of_locks;
      intra_mutex = (pthread_mutex_t *)ap_palloc(p, intra_lock_count * sizeof(pthread_mutex_t ));
      for (i = 0; i < intra_lock_count; i++) {
          if (pthread_mutex_init(&intra_mutex[i], NULL) != 0) {
              perror("intra_mutex_init");
  	    clean_child_exit(APEXIT_CHILDFATAL);
          }
      }
      ap_register_cleanup(p, NULL, intra_mutex_cleanup, ap_null_cleanup);
  }
  
  void intra_mutex_on(int locknum)
  {
      if ((errno = pthread_mutex_lock(&intra_mutex[locknum])) != 0) {
          ap_log_error(APLOG_MARK, APLOG_EMERG, 
  		     (const server_rec *) ap_get_server_conf(),
  		     "Error getting intraprocess lock. Exiting!");
      }
  }
  
  void intra_mutex_off(int locknum)
  {
      if (pthread_mutex_unlock(&intra_mutex[locknum]) != 0) {
          ap_log_error(APLOG_MARK, APLOG_EMERG, 
  		     (const server_rec *) ap_get_server_conf(),
  		     "Error releasing intraprocess lock. Exiting!");
      }
  }
  
  #if defined(USE_FCNTL_SERIALIZED_ACCEPT) || defined(USE_FLOCK_SERIALIZED_ACCEPT)
  static void init_lock_fname(pool *p)
  {
      /* XXXX possibly bogus cast */
      ap_lock_fname = ap_psprintf(p, "%s.%lu",
          ap_server_root_relative(p, ap_lock_fname), (unsigned long)getpid());
  }
  
  static char * expand_lock_fname(pool *p, int i)
  {
      return ap_psprintf(p, "%s.%d", ap_lock_fname, i);
  }
  #endif
  
  #if defined (USE_USLOCK_SERIALIZED_ACCEPT)
  /* XXX - Don't know if we need the intraprocess locks here */
  
  #include <ulocks.h>
  #include "mpm_default.h"
  
  static ulock_t *uslock = NULL;
  
  void accept_mutex_init(pool *p, int number_of_locks)
  {
      ptrdiff_t old;
      usptr_t *us;
      int i;
  
      lock_count = number_of_locks;
      uslock = (ulock_t *)ap_palloc(p, lock_count * sizeof(ulock_t));
  
      for (i = 0; i < lock_count; i++) {
      /* default is 8, allocate enough for all the children plus the parent */
          if ((old = usconfig(CONF_INITUSERS, HARD_SERVER_LIMIT + 1)) == -1) {
  	    perror("usconfig(CONF_INITUSERS)");
  	    exit(-1);
  	}
  	
  	if ((old = usconfig(CONF_LOCKTYPE, US_NODEBUG)) == -1) {
  	    perror("usconfig(CONF_LOCKTYPE)");
  	    exit(-1);
  	}
  	if ((old = usconfig(CONF_ARENATYPE, US_SHAREDONLY)) == -1) {
  	    perror("usconfig(CONF_ARENATYPE)");
  	    exit(-1);
  	}
  	if ((us = usinit("/dev/zero")) == NULL) {
  	    perror("usinit");
  	    exit(-1);
  	}
  	
  	if ((uslock[i] = usnewlock(us)) == NULL) {
  	    perror("usnewlock");
  	    exit(-1);
  	}
      }
  }
  
  void accept_mutex_on(int locknum)
  {
      switch (ussetlock(uslock[locknum])) {
      case 1:
  	/* got lock */
  	break;
      case 0:
  	fprintf(stderr, "didn't get lock\n");
  	clean_child_exit(APEXIT_CHILDFATAL);
      case -1:
  	perror("ussetlock");
  	clean_child_exit(APEXIT_CHILDFATAL);
      }
  }
  
  void accept_mutex_off(int locknum)
  {
      if (usunsetlock(uslock[locknum]) == -1) {
  	perror("usunsetlock");
  	clean_child_exit(APEXIT_CHILDFATAL);
      }
  }
  
  #elif defined (USE_PTHREAD_SERIALIZED_ACCEPT)
  
  /* This code probably only works on Solaris ... but it works really fast
   * on Solaris.  Note that pthread mutexes are *NOT* released when a task
   * dies ... the task has to free it itself.  So we block signals and
   * try to be nice about releasing the mutex.
   */
  
  #include <pthread.h>
  
  static pthread_mutex_t *accept_mutex = (void *)(caddr_t) -1;
  static int *have_accept_mutex;
  /* The sections surrounded with this ifdef are not needed because of the
   * sigwait thread. They may be turned back on, though, depending on how the
   * port to nonthreaded mode goes */
  #ifdef NEED_TO_BLOCK_SIGNALS_AROUND_PTHREAD_CALLS
  static sigset_t accept_block_mask;
  static sigset_t *accept_previous_masks = NULL;
  #endif
  
  void accept_mutex_child_cleanup(void *foo)
  {
      int i;
     
      if (accept_mutex != (void *)(caddr_t)-1) {
          for (i = 0; i < lock_count; i++) {
  	    if (have_accept_mutex[i]) {
    	        pthread_mutex_unlock(&accept_mutex[i]);
              }
  	}
      }
  }
  void accept_mutex_child_init(pool *p)
  {
      ap_register_cleanup(p, NULL, accept_mutex_child_cleanup, ap_null_cleanup);
  #ifdef NEED_TO_BLOCK_SIGNALS_AROUND_PTHREAD_CALLS
      accept_previous_masks = ap_palloc(p, lock_count * sizeof(sigset_t));
  #endif
  }
  
  void accept_mutex_cleanup(void *foo)
  {
      int i;
     
      if (accept_mutex != (void *)(caddr_t)-1
          && munmap((caddr_t) accept_mutex,
                    sizeof(pthread_mutex_t) * lock_count)) {
  	perror("munmap");
      }
      accept_mutex = (void *)(caddr_t)-1;
  }
  
  void accept_mutex_init(pool *p, int number_of_locks)
  {
      pthread_mutexattr_t mattr;
      int fd;
      int i;
     
      lock_count = number_of_locks;
      have_accept_mutex = (int *)ap_palloc(p, 
  		    lock_count * sizeof(int));
  
      fd = open("/dev/zero", O_RDWR);
      if (fd == -1) {
          perror("open(/dev/zero)");
          exit(APEXIT_INIT);
      }
      accept_mutex = (pthread_mutex_t *) mmap((caddr_t) 0, 
                             sizeof(pthread_mutex_t) * lock_count, 
      			   PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
      if (accept_mutex == (void *) (caddr_t) - 1) {
          perror("mmap");
          exit(APEXIT_INIT);
      }
      close(fd);
      if ((errno = pthread_mutexattr_init(&mattr))) {
          perror("pthread_mutexattr_init");
          exit(APEXIT_INIT);
      }
      if ((errno = pthread_mutexattr_setpshared(&mattr,
      					  PTHREAD_PROCESS_SHARED))) {
          perror("pthread_mutexattr_setpshared");
          exit(APEXIT_INIT);
      }
      for (i = 0; i < lock_count; i++) {
  	if ((errno = pthread_mutex_init(&accept_mutex[i], &mattr))) {
  	    perror("pthread_mutex_init");
  	    exit(APEXIT_INIT);
  	}
      }
      if ((errno = pthread_mutexattr_destroy(&mattr))) {
          perror("pthread_mutexattr_destroy");
          exit(APEXIT_INIT);
      }
  #ifdef NEED_TO_BLOCK_SIGNALS_AROUND_PTHREAD_CALLS
      sigfillset(&accept_block_mask);
      sigdelset(&accept_block_mask, SIGHUP);
      sigdelset(&accept_block_mask, SIGTERM);
      sigdelset(&accept_block_mask, SIGWINCH);
  #endif
      ap_register_cleanup(p, NULL, accept_mutex_cleanup, ap_null_cleanup);
  }
  
  void accept_mutex_on(int locknum)
  {
      int err;
  
  #ifdef NEED_TO_BLOCK_SIGNALS_AROUND_PTHREAD_CALLS
      if (pthread_sigmask(SIG_BLOCK, &accept_block_mask,
                          &accept_previous_mask[locknum])) {
  	perror("pthread_sigmask(SIG_BLOCK)");
  	clean_child_exit(APEXIT_CHILDFATAL);
      }
  #endif
      if ((err = pthread_mutex_lock(&accept_mutex[locknum]))) {
  	errno = err;
  	perror("pthread_mutex_lock");
  	clean_child_exit(APEXIT_CHILDFATAL);
      }
      have_accept_mutex[locknum] = 1;
  }
  
  void accept_mutex_off(int locknum)
  {
      int err;
  
      if ((err = pthread_mutex_unlock(&accept_mutex[locknum]))) {
  	errno = err;
  	perror("pthread_mutex_unlock");
  	clean_child_exit(APEXIT_CHILDFATAL);
      }
      /* There is a slight race condition right here... if we were to die right
       * now, we'd do another pthread_mutex_unlock.  Now, doing that would let
       * another process into the mutex.  pthread mutexes are designed to be
       * fast, as such they don't have protection for things like testing if the
       * thread owning a mutex is actually unlocking it (or even any way of
       * testing who owns the mutex).
       *
       * If we were to unset have_accept_mutex prior to releasing the mutex
       * then the race could result in the server unable to serve hits.  Doing
       * it this way means that the server can continue, but an additional
       * child might be in the critical section ... at least it's still serving
       * hits.
       */
      have_accept_mutex[locknum] = 0;
  #ifdef NEED_TO_BLOCK_SIGNALS_AROUND_PTHREAD_CALLS
      if (pthread_sigmask(SIG_SETMASK, &accept_previous_mask[locknum], NULL)) {
  	perror("pthread_sigmask(SIG_SETMASK)");
  	clean_child_exit(1);
      }
  #endif
  }
  
  #elif defined (USE_SYSVSEM_SERIALIZED_ACCEPT)
  
  #include <sys/types.h>
  #include <sys/ipc.h>
  #include <sys/sem.h>
  
  #ifdef NEED_UNION_SEMUN
  /* it makes no sense, but this isn't defined on solaris */
  union semun {
      long val;
      struct semid_ds *buf;
      ushort *array;
  };
  
  #endif
  
  static int *sem_id = NULL;
  static struct sembuf op_on;
  static struct sembuf op_off;
  
  /* We get a random semaphore ... the lame sysv semaphore interface
   * means we have to be sure to clean this up or else we'll leak
   * semaphores.
   */
  void accept_mutex_cleanup(void *foo)
  {
      union semun ick;
      int i;
  
      for (i = 0; i < lock_count; i++) {
          if (sem_id[i] < 0)
  	  return;
  	/* this is ignored anyhow */
  	ick.val = 0;
  	semctl(sem_id[i], 0, IPC_RMID, ick);
      }
  }
  
  
  
  void accept_mutex_init(pool *p, int number_of_locks)
  {
      union semun ick;
      struct semid_ds buf;
      int i;
     
      lock_count = number_of_locks;
      sem_id = (int *)ap_palloc(p, lock_count * sizeof(int));
  
      for (i = 0; i < lock_count; i++) {
          /* acquire the semaphore */
          sem_id[i] = semget(IPC_PRIVATE, 1, IPC_CREAT | 0600);
  	if (sem_id[i] < 0) {
  	    perror("semget");
  	    exit(APEXIT_INIT);
  	}
  	ick.val = 1;
  	if (semctl(sem_id[i], 0, SETVAL, ick) < 0) {
  	    perror("semctl(SETVAL)");
  	    exit(APEXIT_INIT);
  	}
  	if (!getuid()) {
  	  /* restrict it to use only by the appropriate user_id ... not that this
  	   * stops CGIs from acquiring it and dinking around with it.
  	   */
  	    buf.sem_perm.uid = unixd_config.user_id;
  	    buf.sem_perm.gid = unixd_config.group_id;
  	    buf.sem_perm.mode = 0600;
  	    ick.buf = &buf;
  	    if (semctl(sem_id[i], 0, IPC_SET, ick) < 0) {
  	      perror("semctl(IPC_SET)");
  	      exit(APEXIT_INIT);
  	    }
  	}
  	ap_register_cleanup(p, NULL, accept_mutex_cleanup, ap_null_cleanup);
  
  	/* pre-initialize these */
  	op_on.sem_num = 0;
  	op_on.sem_op = -1;
  	op_on.sem_flg = SEM_UNDO;
  	op_off.sem_num = 0;
  	op_off.sem_op = 1;
  	op_off.sem_flg = SEM_UNDO;
      }
  }
  
  void accept_mutex_on(int locknum)
  {
      if (semop(sem_id[locknum], &op_on, 1) < 0) {
  	perror("accept_mutex_on");
  	clean_child_exit(APEXIT_CHILDFATAL);
      }
  }
  
  void accept_mutex_off(int locknum)
  {
      if (semop(sem_id[locknum], &op_off, 1) < 0) {
  	perror("accept_mutex_off");
  	clean_child_exit(APEXIT_CHILDFATAL);
      }
  }
  
  #elif defined(USE_FCNTL_SERIALIZED_ACCEPT)
  static struct flock lock_it;
  static struct flock unlock_it;
  
  static int *lock_fd = NULL;
  
  /*
   * Initialize mutex lock.
   * Must be safe to call this on a restart.
   */
  void accept_mutex_init(pool *p, int number_of_locks)
  {
      int i;
      char * lock_fname;
  
      lock_count = number_of_locks;
      lock_fd = (int *)ap_palloc(p, lock_count * sizeof(int *));
      lock_it.l_whence = SEEK_SET;	/* from current point */
      lock_it.l_start = 0;		/* -"- */
      lock_it.l_len = 0;			/* until end of file */
      lock_it.l_type = F_WRLCK;		/* set exclusive/write lock */
      lock_it.l_pid = 0;			/* pid not actually interesting */
      unlock_it.l_whence = SEEK_SET;	/* from current point */
      unlock_it.l_start = 0;		/* -"- */
      unlock_it.l_len = 0;		/* until end of file */
      unlock_it.l_type = F_UNLCK;		/* set exclusive/write lock */
      unlock_it.l_pid = 0;		/* pid not actually interesting */
  
      init_lock_fname(p);
      for (i = 0; i < lock_count; i++) {
          lock_fname = expand_lock_fname(p, i);
  	lock_fd[i] = ap_popenf(p, lock_fname, 
  			       O_CREAT | O_WRONLY | O_EXCL, 0644);
  	if (lock_fd[i] == -1) {
  	    perror("open");
  	    fprintf(stderr, "Cannot open lock file: %s\n", lock_fname);
  	    exit(APEXIT_INIT);
  	}
  	unlink(lock_fname);
      }
  }
  
  void accept_mutex_on(int locknum)
  {
      int ret;
  
      while ((ret = fcntl(lock_fd[locknum], F_SETLKW, &lock_it)) < 0 && 
  	   errno == EINTR) {
  	/* nop */
      }
  
      if (ret < 0) {
  	ap_log_error(APLOG_MARK, APLOG_EMERG, (const server_rec*) ap_get_server_conf(),
  		    "fcntl: F_SETLKW: Error getting accept lock, exiting!  "
  		    "Perhaps you need to use the LockFile directive to place "
  		    "your lock file on a local disk!");
  	clean_child_exit(APEXIT_CHILDFATAL);
      }
  }
  
  void accept_mutex_off(int locknum)
  {
      int ret;
  
      while ((ret = fcntl(lock_fd[locknum], F_SETLKW, &unlock_it)) < 0 
  	   && errno == EINTR) {
  	/* nop */
      }
      if (ret < 0) {
  	ap_log_error(APLOG_MARK, APLOG_EMERG, (const server_rec*) ap_get_server_conf(),
  		    "fcntl: F_SETLKW: Error freeing accept lock, exiting!  "
  		    "Perhaps you need to use the LockFile directive to place "
  		    "your lock file on a local disk!");
  	clean_child_exit(APEXIT_CHILDFATAL);
      }
  }
  
  #elif defined(USE_FLOCK_SERIALIZED_ACCEPT)
  
  static int *lock_fd = NULL;
  
  void accept_mutex_cleanup(void *foo)
  {
      int i;
    
      char * lock_fname;
      for (i = 0; i < lock_count; i++) {
          lock_fname = expand_lock_fname(foo, i);
          unlink(lock_fname);
      }
  }
  
  /*
   * Initialize mutex lock.
   * Done by each child at it's birth
   */ 
  void accept_mutex_child_init(pool *p)
  {
      int i;
    
      for (i = 0; i < lock_count; i++) {
          char *lock_fname = expand_lock_fname(p, i);
      
          lock_fd[i] = ap_popenf(p, lock_fname, O_WRONLY, 0600);
          if (lock_fd[i] == -1) {
  	  ap_log_error(APLOG_MARK, APLOG_EMERG, 
  		       (const server_rec *)ap_get_server_conf(),
  		       "Child cannot open lock file: %s", lock_fname);
  	  clean_child_exit(APEXIT_CHILDINIT);
          }
      }
  }
  
  /*
   * Initialize mutex lock.
   * Must be safe to call this on a restart.
   */
  void accept_mutex_init(pool *p, int number_of_locks)
  {
      int i;
      char *lock_fname;
    
      lock_count = number_of_locks;
      lock_fd = (int *)ap_palloc(p, lock_count * sizeof(int *));
      init_lock_fname(p);
      for (i = 0; i < lock_count; i++) {
          lock_fname = expand_lock_fname(p, i);
          unlink(lock_fname);
          lock_fd[i] = ap_popenf(p, lock_fname, 
  			       O_CREAT | O_WRONLY | O_EXCL, 0600);
          if (lock_fd[i] == -1) {
  	    ap_log_error(APLOG_MARK, APLOG_EMERG, 
  			 (const server_rec *) ap_get_server_conf(), 
  			 "Parent cannot open lock file: %s", lock_fname);
              exit(APEXIT_INIT);
          }
          ap_register_cleanup(p, p, accept_mutex_cleanup, ap_null_cleanup);
      }
  }
  
  void accept_mutex_on(int locknum)
  {
      int ret;
  
      while ((ret = flock(lock_fd[locknum], LOCK_EX)) < 0 && errno == EINTR)
          continue;
  
      if (ret < 0) {
          ap_log_error(APLOG_MARK, APLOG_EMERG, 
  		     (const server_rec *) ap_get_server_conf(),
  		     "flock: LOCK_EX: Error getting accept lock. Exiting!");
  	clean_child_exit(APEXIT_CHILDFATAL);
      }
  }
  
  void accept_mutex_off(int locknum)
  {
      if (flock(lock_fd[locknum], LOCK_UN) < 0) {
          ap_log_error(APLOG_MARK, APLOG_EMERG, 
  		     (const server_rec *) ap_get_server_conf(),
  		     "flock: LOCK_UN: Error freeing accept lock. Exiting!");
  	clean_child_exit(APEXIT_CHILDFATAL);
      }
  }
  
  #elif defined(USE_OS2SEM_SERIALIZED_ACCEPT)
  
  static HMTX *lock_sem = NULL;
  
  void accept_mutex_cleanup(void *foo)
  { 
      int i;
    
      for (i = 0; i < lock_count; i++) {
          DosReleaseMutexSem(lock_sem[i]);
  	DosCloseMutexSem(lock_sem[i]);
      }
  }
  
  /*
   * Initialize mutex lock.
   * Done by each child at it's birth
   */
  void accept_mutex_child_init(pool *p)
  {
      int i;
      
      for(i = 0; i < lock_count; i++) {
          int rc = DosOpenMutexSem(NULL, &lock_sem[locknum]);
  
  	if (rc != 0) {
  	    ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_EMERG, ap_get_server_conf(),
  			 "Child cannot open lock semaphore, rc=%d", rc);
  	    clean_child_exit(APEXIT_CHILDINIT);
  	}
      }
  }
  /*
   * Initialize mutex lock.
   * Must be safe to call this on a restart.
   */
  void accept_mutex_init(pool *p, int number_of_locks)
  {
      int rc;
      int i;
  
      lock_count = number_of_locks;
      lock_fd = (int *)ap_palloc(p, lock_count * sizeof(int *));
  
      for (i = 0; i < lock_count; i++) {
          rc = DosCreateMutexSem(NULL, &lock_sem[i], DC_SEM_SHARED, FALSE);
  
  	if (rc != 0) {
  	  ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_EMERG, ap_get_server_conf(),
  		       "Parent cannot create lock semaphore, rc=%d", rc);
  	  exit(APEXIT_INIT);
  	}
  	
  	ap_register_cleanup(p, NULL, accept_mutex_cleanup, ap_null_cleanup);
      }
  }
  
  void accept_mutex_on(int locknum)
  {
      int rc = DosRequestMutexSem(lock_sem[locknum], SEM_INDEFINITE_WAIT);
  
      if (rc != 0) {
  	ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_EMERG, ap_get_server_conf(),
  		    "OS2SEM: Error %d getting accept lock. Exiting!", rc);
  	clean_child_exit(APEXIT_CHILDFATAL);
      }
  }
  
  void accept_mutex_off(int locknum)
  {
      int rc = DosReleaseMutexSem(lock_sem[locknum]);
      
      if (rc != 0) {
  	ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_EMERG, ap_get_server_conf(),
  		    "OS2SEM: Error %d freeing accept lock. Exiting!", rc);
  	clean_child_exit(APEXIT_CHILDFATAL);
      }
  }
  
  #elif defined(USE_TPF_CORE_SERIALIZED_ACCEPT)
  
  static int tpf_core_held;
  
  static void accept_mutex_cleanup(void *foo)
  {
      if(tpf_core_held)
          coruc(RESOURCE_KEY);
  }
  
  #define accept_mutex_init(x)
  
  static void accept_mutex_child_init(pool *p)
  {
      ap_register_cleanup(p, NULL, accept_mutex_cleanup, ap_null_cleanup);
      tpf_core_held = 0;
  }
  
  static void accept_mutex_on(void)
  {
      corhc(RESOURCE_KEY);
      tpf_core_held = 1;
      ap_check_signals();
  }
  
  static void accept_mutex_off(void)
  {
      coruc(RESOURCE_KEY);
      tpf_core_held = 0;
      ap_check_signals();
  }
  
  #else
  /* Default --- no serialization.  Other methods *could* go here,
   * as #elifs...
   */
  #if !defined(MULTITHREAD)
  /* Multithreaded systems don't complete between processes for
   * the sockets. */
  
  #endif
  #endif
  
  
  
  
  1.1                  apache-2.0/mpm/src/modules/mpm/dexter/acceptlock.h
  
  Index: acceptlock.h
  ===================================================================
  /* ====================================================================
   * Copyright (c) 1995-1999 The Apache Group.  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. All advertising materials mentioning features or use of this 
   *    software must display the following acknowledgment: 
   *    "This product includes software developed by the Apache Group 
   *    for use in the Apache HTTP server project (http://www.apache.org/)." 
   * 
   * 4. The names "Apache Server" and "Apache Group" must not be used to 
   *    endorse or promote products derived from this software without 
   *    prior written permission. For written permission, please contact 
   *    apache@apache.org. 
   * 
   * 5. Products derived from this software may not be called "Apache" 
   *    nor may "Apache" appear in their names without prior written 
   *    permission of the Apache Group. 
   * 
   * 6. Redistributions of any form whatsoever must retain the following 
   *    acknowledgment: 
   *    "This product includes software developed by the Apache Group 
   *    for use in the Apache HTTP server project (http://www.apache.org/)." 
   * 
   * THIS SOFTWARE IS PROVIDED BY THE APACHE GROUP ``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 GROUP 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 Group and was originally based 
   * on public domain software written at the National Center for 
   * Supercomputing Applications, University of Illinois, Urbana-Champaign. 
   * For more information on the Apache Group and the Apache HTTP server 
   * project, please see <http://www.apache.org/>. 
   * 
   */ 
  
  #ifndef APACHE_ACCEPT_LOCK_H
  #define APACHE_ACCEPT_LOCK_H
  
  #ifdef __cplusplus
  extern "C" {
  #endif
    
  /* TODO: Maybe this should be hidden behind a function call. Haven't decided
   * exactly how, yet */
  extern char *ap_lock_fname;
  
  /* Lock file prefix, needed only for initial configuration */
  /* Prototypes for the intraprocess accept mutex functions */
  void intra_mutex_init(pool *p, int);
  void intra_mutex_on(int);
  void intra_mutex_off(int);
  
  /* Prototyps for the accept mutex functions. */
  #if defined (USE_USLOCK_SERIALIZED_ACCEPT)
  #define accept_mutex_child_init(x)
  void accept_mutex_init(pool *, int);
  void accept_mutex_on(int);
  void accept_mutex_off(int);
  
  #elif defined (USE_PTHREAD_SERIALIZED_ACCEPT)
  void accept_mutex_child_cleanup(void *);
  void accept_mutex_child_init(pool *);
  void accept_mutex_cleanup(void *);
  void accept_mutex_init(pool *, int);
  void accept_mutex_on(int);
  void accept_mutex_off(int);
  
  #elif defined (USE_SYSVSEM_SERIALIZED_ACCEPT)
  void accept_mutex_cleanup(void *);
  #define accept_mutex_child_init(x)
  void accept_mutex_init(pool *, int);
  void accept_mutex_on(int);
  void accept_mutex_off(int);
  
  #elif defined(USE_FCNTL_SERIALIZED_ACCEPT)
  #define accept_mutex_child_init(x)
  void accept_mutex_init(pool *, int);
  void accept_mutex_on(int);
  void accept_mutex_off(int);
  
  #elif defined(USE_FLOCK_SERIALIZED_ACCEPT)
  void accept_mutex_cleanup(void *);
  void accept_mutex_child_init(pool *);
  void accept_mutex_init(pool *, int);
  void accept_mutex_on(int);
  void accept_mutex_off(int);
  
  #elif defined(USE_OS2SEM_SERIALIZED_ACCEPT)
  void accept_mutex_cleanup(void *);
  void accept_mutex_child_init(pool *);
  void accept_mutex_init(pool *, int);
  void accept_mutex_on(int);
  void accept_mutex_off(int);
  
  #else
  #if !defined(MULTITHREAD)
  /* Multithreaded systems don't complete between processes for
   * the sockets. */
  #define NO_SERIALIZED_ACCEPT
  #define accept_mutex_child_init(x)
  #define accept_mutex_init(x, y)
  #define accept_mutex_on(x)
  #define accept_mutex_off(x)
  #endif
  #endif
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif /* APACHE_ACCEPT_LOCK_H */
  
  
  
  1.1                  apache-2.0/mpm/src/modules/mpm/dexter/dexter.c
  
  Index: dexter.c
  ===================================================================
  /* ====================================================================
   * Copyright (c) 1995-1999 The Apache Group.  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. All advertising materials mentioning features or use of this 
   *    software must display the following acknowledgment: 
   *    "This product includes software developed by the Apache Group 
   *    for use in the Apache HTTP server project (http://www.apache.org/)." 
   * 
   * 4. The names "Apache Server" and "Apache Group" must not be used to 
   *    endorse or promote products derived from this software without 
   *    prior written permission. For written permission, please contact 
   *    apache@apache.org. 
   * 
   * 5. Products derived from this software may not be called "Apache" 
   *    nor may "Apache" appear in their names without prior written 
   *    permission of the Apache Group. 
   * 
   * 6. Redistributions of any form whatsoever must retain the following 
   *    acknowledgment: 
   *    "This product includes software developed by the Apache Group 
   *    for use in the Apache HTTP server project (http://www.apache.org/)." 
   * 
   * THIS SOFTWARE IS PROVIDED BY THE APACHE GROUP ``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 GROUP 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 Group and was originally based 
   * on public domain software written at the National Center for 
   * Supercomputing Applications, University of Illinois, Urbana-Champaign. 
   * For more information on the Apache Group and the Apache HTTP server 
   * project, please see <http://www.apache.org/>. 
   * 
   */ 
   
  #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 "ap_mpm.h"
  #include "unixd.h"
  #include "iol_socket.h"
  #include "ap_listen.h"
  #include "scoreboard.h" 
  #include "acceptlock.h"
  
  #include <poll.h>
  #include <netinet/tcp.h> 
  #include <pthread.h>
  
  /*
   * Actual definitions of config globals
   */
  
  int ap_threads_per_child=0;         /* Worker threads per child */
  int ap_max_requests_per_child=0;
  static char *ap_pid_fname=NULL;
  static int ap_num_daemons=0;
  static time_t ap_restart_time=0;
  API_VAR_EXPORT int ap_extended_status = 0;
  static int workers_may_exit = 0;
  static int requests_this_child;
  static int num_listenfds = 0;
  static struct pollfd *listenfds;
  
  /* The structure used to pass unique initialization info to each thread */
  typedef struct {
      int pid;
      int tid;
      int sd;
      pool *tpool; /* "pthread" would be confusing */
  } proc_info;
  
  #if 0
  #define SAFE_ACCEPT(stmt) do {if (ap_listeners->next != NULL) {stmt;}} while (0)
  #else
  #define SAFE_ACCEPT(stmt) do {stmt;} while (0)
  #endif
  
  /*
   * The max child slot ever assigned, preserved across restarts.  Necessary
   * to deal with NumServers changes across SIGWINCH restarts.  We use this
   * value to optimize routines that have to scan the entire scoreboard.
   */
  int max_daemons_limit = -1;
  
  
  static char ap_coredump_dir[MAX_STRING_LEN];
  
  static int pipe_of_death[2];
  static pthread_mutex_t pipe_of_death_mutex;
  
  /* *Non*-shared http_main globals... */
  
  static server_rec *server_conf;
  
  /* one_process --- debugging mode variable; can be set from the command line
   * with the -X flag.  If set, this gets you the child_main loop running
   * in the process which originally started up (no detach, no make_child),
   * which is a pretty nice debugging environment.  (You'll get a SIGHUP
   * early in standalone_main; just continue through.  This is the server
   * trying to kill off any child processes which it might have lying
   * around --- Apache doesn't keep track of their pids, it just sends
   * SIGHUP to the process group, ignoring it in the root process.
   * Continue through and you'll be fine.).
   */
  
  static int one_process = 0;
  
  #ifdef DEBUG_SIGSTOP
  int raise_sigstop_flags;
  #endif
  
  #ifdef HAS_OTHER_CHILD
  /* used to maintain list of children which aren't part of the scoreboard */
  typedef struct other_child_rec other_child_rec;
  struct other_child_rec {
      other_child_rec *next;
      int pid;
      void (*maintenance) (int, void *, ap_wait_t);
      void *data;
      int write_fd;
  };
  static other_child_rec *other_children;
  #endif
  
  static pool *pconf;		/* Pool for config stuff */
  static pool *pchild;		/* Pool for httpd child stuff */
  
  static int my_pid; /* Linux getpid() doesn't work except in main thread. Use
                        this instead */
  /* Keep track of the number of worker threads currently active */
  static int worker_thread_count;
  static pthread_mutex_t worker_thread_count_mutex;
  
  /* Global, alas, so http_core can talk to us */
  enum server_token_type ap_server_tokens = SrvTk_FULL;
  
  API_EXPORT(const server_rec *) ap_get_server_conf(void)
  {
      return (server_conf);
  }
  
  /* a clean exit from a child with proper cleanup 
     static void clean_child_exit(int code) __attribute__ ((noreturn)); */
  void clean_child_exit(int code)
  {
      if (pchild) {
  	ap_destroy_pool(pchild);
      }
      exit(code);
  }
  
  /*****************************************************************
   * dealing with other children
   */
  
  #ifdef HAS_OTHER_CHILD
  API_EXPORT(void) ap_register_other_child(int pid,
  		       void (*maintenance) (int reason, void *, ap_wait_t status),
  			  void *data, int write_fd)
  {
      other_child_rec *ocr;
  
      ocr = ap_palloc(pconf, sizeof(*ocr));
      ocr->pid = pid;
      ocr->maintenance = maintenance;
      ocr->data = data;
      ocr->write_fd = write_fd;
      ocr->next = other_children;
      other_children = ocr;
  }
  
  /* note that since this can be called by a maintenance function while we're
   * scanning the other_children list, all scanners should protect themself
   * by loading ocr->next before calling any maintenance function.
   */
  API_EXPORT(void) ap_unregister_other_child(void *data)
  {
      other_child_rec **pocr, *nocr;
  
      for (pocr = &other_children; *pocr; pocr = &(*pocr)->next) {
  	if ((*pocr)->data == data) {
  	    nocr = (*pocr)->next;
  	    (*(*pocr)->maintenance) (OC_REASON_UNREGISTER, (*pocr)->data, -1);
  	    *pocr = nocr;
  	    /* XXX: um, well we've just wasted some space in pconf ? */
  	    return;
  	}
      }
  }
  
  /* test to ensure that the write_fds are all still writable, otherwise
   * invoke the maintenance functions as appropriate */
  static void probe_writable_fds(void)
  {
      return;
  #if 0
      fd_set writable_fds;
      int fd_max;
      other_child_rec *ocr, *nocr;
      struct timeval tv;
      int rc;
  
      if (other_children == NULL)
  	return;
  
      fd_max = 0;
      FD_ZERO(&writable_fds);
      do {
  	for (ocr = other_children; ocr; ocr = ocr->next) {
  	    if (ocr->write_fd == -1)
  		continue;
  	    FD_SET(ocr->write_fd, &writable_fds);
  	    if (ocr->write_fd > fd_max) {
  		fd_max = ocr->write_fd;
  	    }
  	}
  	if (fd_max == 0)
  	    return;
  
  	tv.tv_sec = 0;
  	tv.tv_usec = 0;
  	rc = ap_select(fd_max + 1, NULL, &writable_fds, NULL, &tv);
      } while (rc == -1 && errno == EINTR);
  
      if (rc == -1) {
  	/* XXX: uhh this could be really bad, we could have a bad file
  	 * descriptor due to a bug in one of the maintenance routines */
  	ap_log_unixerr("probe_writable_fds", "select",
  		    "could not probe writable fds", server_conf);
  	return;
      }
      if (rc == 0)
  	return;
  
      for (ocr = other_children; ocr; ocr = nocr) {
  	nocr = ocr->next;
  	if (ocr->write_fd == -1)
  	    continue;
  	if (FD_ISSET(ocr->write_fd, &writable_fds))
  	    continue;
  	(*ocr->maintenance) (OC_REASON_UNWRITABLE, ocr->data, -1);
      }
  #endif
  }
  
  /* possibly reap an other_child, return 0 if yes, -1 if not */
  static int reap_other_child(int pid, ap_wait_t status)
  {
      other_child_rec *ocr, *nocr;
  
      for (ocr = other_children; ocr; ocr = nocr) {
  	nocr = ocr->next;
  	if (ocr->pid != pid)
  	    continue;
  	ocr->pid = -1;
  	(*ocr->maintenance) (OC_REASON_DEATH, ocr->data, status);
  	return 0;
      }
      return -1;
  }
  #endif
  
  static void reclaim_child_processes(int terminate)
  {
      int i, status;
      long int waittime = 1024 * 16;	/* in usecs */
      struct timeval tv;
      int waitret, tries;
      int not_dead_yet;
  #ifdef HAS_OTHER_CHILD
      other_child_rec *ocr, *nocr;
  #endif
  
      for (tries = terminate ? 4 : 1; tries <= 9; ++tries) {
  	/* don't want to hold up progress any more than 
  	 * necessary, but we need to allow children a few moments to exit.
  	 * Set delay with an exponential backoff.
  	 */
  	tv.tv_sec = waittime / 1000000;
  	tv.tv_usec = waittime % 1000000;
  	waittime = waittime * 4;
  	ap_select(0, NULL, NULL, NULL, &tv);
  
  	/* now see who is done */
  	not_dead_yet = 0;
  	for (i = 0; i < max_daemons_limit; ++i) {
  	    int pid = ap_scoreboard_image[i].pid;
  
  	    if (pid == my_pid || pid == 0)
  		continue;
  
  	    waitret = waitpid(pid, &status, WNOHANG);
  	    if (waitret == pid || waitret == -1) {
  		ap_scoreboard_image[i].pid = 0;
  		continue;
  	    }
  	    ++not_dead_yet;
  	    switch (tries) {
  	    case 1:     /*  16ms */
  	    case 2:     /*  82ms */
  		break;
  	    case 3:     /* 344ms */
  	    case 4:     /*  16ms */
  	    case 5:     /*  82ms */
  	    case 6:     /* 344ms */
  	    case 7:     /* 1.4sec */
  		/* ok, now it's being annoying */
  		ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_WARNING,
  			    server_conf,
  		   "child process %d still did not exit, sending a SIGTERM",
  			    pid);
  		kill(pid, SIGTERM);
  		break;
  	    case 8:     /*  6 sec */
  		/* die child scum */
  		ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_ERR, server_conf,
  		   "child process %d still did not exit, sending a SIGKILL",
  			    pid);
  		kill(pid, SIGKILL);
  		break;
  	    case 9:     /* 14 sec */
  		/* gave it our best shot, but alas...  If this really 
  		 * is a child we are trying to kill and it really hasn't
  		 * exited, we will likely fail to bind to the port
  		 * after the restart.
  		 */
  		ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_ERR, server_conf,
  			    "could not make child process %d exit, "
  			    "attempting to continue anyway", pid);
  		break;
  	    }
  	}
  #ifdef HAS_OTHER_CHILD
  	for (ocr = other_children; ocr; ocr = nocr) {
  	    nocr = ocr->next;
  	    if (ocr->pid == -1)
  		continue;
  
  	    waitret = waitpid(ocr->pid, &status, WNOHANG);
  	    if (waitret == ocr->pid) {
  		ocr->pid = -1;
  		(*ocr->maintenance) (OC_REASON_DEATH, ocr->data, status);
  	    }
  	    else if (waitret == 0) {
  		(*ocr->maintenance) (OC_REASON_RESTART, ocr->data, -1);
  		++not_dead_yet;
  	    }
  	    else if (waitret == -1) {
  		/* uh what the heck? they didn't call unregister? */
  		ocr->pid = -1;
  		(*ocr->maintenance) (OC_REASON_LOST, ocr->data, -1);
  	    }
  	}
  #endif
  	if (!not_dead_yet) {
  	    /* nothing left to wait for */
  	    break;
  	}
      }
  }
  
  /* Finally, this routine is used by the caretaker process to wait for
   * a while...
   */
  
  /* number of calls to wait_or_timeout between writable probes */
  #ifndef INTERVAL_OF_WRITABLE_PROBES
  #define INTERVAL_OF_WRITABLE_PROBES 10
  #endif
  static int wait_or_timeout_counter;
  
  static int wait_or_timeout(ap_wait_t *status)
  {
      struct timeval tv;
      int ret;
  
      ++wait_or_timeout_counter;
      if (wait_or_timeout_counter == INTERVAL_OF_WRITABLE_PROBES) {
  	wait_or_timeout_counter = 0;
  #ifdef HAS_OTHER_CHILD
  	probe_writable_fds();
  #endif
      }
      ret = waitpid(-1, status, WNOHANG);
      if (ret == -1 && errno == EINTR) {
  	return -1;
      }
      if (ret > 0) {
  	return ret;
      }
      tv.tv_sec = SCOREBOARD_MAINTENANCE_INTERVAL / 1000000;
      tv.tv_usec = SCOREBOARD_MAINTENANCE_INTERVAL % 1000000;
      ap_select(0, NULL, NULL, NULL, &tv);
      return -1;
  }
  
  #if defined(NSIG)
  #define NumSIG NSIG
  #elif defined(_NSIG)
  #define NumSIG _NSIG
  #elif defined(__NSIG)
  #define NumSIG __NSIG
  #else
  #define NumSIG 32   /* for 1998's unixes, this is still a good assumption */
  #endif
  
  #ifdef SYS_SIGLIST /* platform has sys_siglist[] */
  #define INIT_SIGLIST()  /*nothing*/
  #else /* platform has no sys_siglist[], define our own */
  #define SYS_SIGLIST ap_sys_siglist
  #define INIT_SIGLIST() siglist_init();
  
  const char *ap_sys_siglist[NumSIG];
  
  static void siglist_init(void)
  {
      int sig;
  
      ap_sys_siglist[0] = "Signal 0";
  #ifdef SIGHUP
      ap_sys_siglist[SIGHUP] = "Hangup";
  #endif
  #ifdef SIGINT
      ap_sys_siglist[SIGINT] = "Interrupt";
  #endif
  #ifdef SIGQUIT
      ap_sys_siglist[SIGQUIT] = "Quit";
  #endif
  #ifdef SIGILL
      ap_sys_siglist[SIGILL] = "Illegal instruction";
  #endif
  #ifdef SIGTRAP
      ap_sys_siglist[SIGTRAP] = "Trace/BPT trap";
  #endif
  #ifdef SIGIOT
      ap_sys_siglist[SIGIOT] = "IOT instruction";
  #endif
  #ifdef SIGABRT
      ap_sys_siglist[SIGABRT] = "Abort";
  #endif
  #ifdef SIGEMT
      ap_sys_siglist[SIGEMT] = "Emulator trap";
  #endif
  #ifdef SIGFPE
      ap_sys_siglist[SIGFPE] = "Arithmetic exception";
  #endif
  #ifdef SIGKILL
      ap_sys_siglist[SIGKILL] = "Killed";
  #endif
  #ifdef SIGBUS
      ap_sys_siglist[SIGBUS] = "Bus error";
  #endif
  #ifdef SIGSEGV
      ap_sys_siglist[SIGSEGV] = "Segmentation fault";
  #endif
  #ifdef SIGSYS
      ap_sys_siglist[SIGSYS] = "Bad system call";
  #endif
  #ifdef SIGPIPE
      ap_sys_siglist[SIGPIPE] = "Broken pipe";
  #endif
  #ifdef SIGALRM
      ap_sys_siglist[SIGALRM] = "Alarm clock";
  #endif
  #ifdef SIGTERM
      ap_sys_siglist[SIGTERM] = "Terminated";
  #endif
  #ifdef SIGUSR1
      ap_sys_siglist[SIGUSR1] = "User defined signal 1";
  #endif
  #ifdef SIGUSR2
      ap_sys_siglist[SIGUSR2] = "User defined signal 2";
  #endif
  #ifdef SIGCLD
      ap_sys_siglist[SIGCLD] = "Child status change";
  #endif
  #ifdef SIGCHLD
      ap_sys_siglist[SIGCHLD] = "Child status change";
  #endif
  #ifdef SIGPWR
      ap_sys_siglist[SIGPWR] = "Power-fail restart";
  #endif
  #ifdef SIGWINCH
      ap_sys_siglist[SIGWINCH] = "Window changed";
  #endif
  #ifdef SIGURG
      ap_sys_siglist[SIGURG] = "urgent socket condition";
  #endif
  #ifdef SIGPOLL
      ap_sys_siglist[SIGPOLL] = "Pollable event occurred";
  #endif
  #ifdef SIGIO
      ap_sys_siglist[SIGIO] = "socket I/O possible";
  #endif
  #ifdef SIGSTOP
      ap_sys_siglist[SIGSTOP] = "Stopped (signal)";
  #endif
  #ifdef SIGTSTP
      ap_sys_siglist[SIGTSTP] = "Stopped";
  #endif
  #ifdef SIGCONT
      ap_sys_siglist[SIGCONT] = "Continued";
  #endif
  #ifdef SIGTTIN
      ap_sys_siglist[SIGTTIN] = "Stopped (tty input)";
  #endif
  #ifdef SIGTTOU
      ap_sys_siglist[SIGTTOU] = "Stopped (tty output)";
  #endif
  #ifdef SIGVTALRM
      ap_sys_siglist[SIGVTALRM] = "virtual timer expired";
  #endif
  #ifdef SIGPROF
      ap_sys_siglist[SIGPROF] = "profiling timer expired";
  #endif
  #ifdef SIGXCPU
      ap_sys_siglist[SIGXCPU] = "exceeded cpu limit";
  #endif
  #ifdef SIGXFSZ
      ap_sys_siglist[SIGXFSZ] = "exceeded file size limit";
  #endif
      for (sig=0; sig < sizeof(ap_sys_siglist)/sizeof(ap_sys_siglist[0]); ++sig)
          if (ap_sys_siglist[sig] == NULL)
              ap_sys_siglist[sig] = "";
  }
  #endif /* platform has sys_siglist[] */
  
  /* handle all varieties of core dumping signals */
  static void sig_coredump(int sig)
  {
      chdir(ap_coredump_dir);
      signal(sig, SIG_DFL);
      kill(getpid(), sig);
      /* At this point we've got sig blocked, because we're still inside
       * the signal handler.  When we leave the signal handler it will
       * be unblocked, and we'll take the signal... and coredump or whatever
       * is appropriate for this particular Unix.  In addition the parent
       * will see the real signal we received -- whereas if we called
       * abort() here, the parent would only see SIGABRT.
       */
  }
  
  static void just_die(int sig)
  {
      clean_child_exit(0);
  }
  
  /*****************************************************************
   * Connection structures and accounting...
   */
  
  /* volatile just in case */
  static int volatile shutdown_pending;
  static int volatile restart_pending;
  static int volatile is_graceful;
  
  /*
   * ap_start_shutdown() and ap_start_restart(), below, are a first stab at
   * functions to initiate shutdown or restart without relying on signals. 
   * Previously this was initiated in sig_term() and restart() signal handlers, 
   * but we want to be able to start a shutdown/restart from other sources --
   * e.g. on Win32, from the service manager. Now the service manager can
   * call ap_start_shutdown() or ap_start_restart() as appropiate.  Note that
   * these functions can also be called by the child processes, since global
   * variables are no longer used to pass on the required action to the parent.
   *
   * These should only be called from the parent process itself, since the
   * parent process will use the shutdown_pending and restart_pending variables
   * to determine whether to shutdown or restart. The child process should
   * call signal_parent() directly to tell the parent to die -- this will
   * cause neither of those variable to be set, which the parent will
   * assume means something serious is wrong (which it will be, for the
   * child to force an exit) and so do an exit anyway.
   */
  
  void ap_start_shutdown(void)
  {
      if (shutdown_pending == 1) {
  	/* Um, is this _probably_ not an error, if the user has
  	 * tried to do a shutdown twice quickly, so we won't
  	 * worry about reporting it.
  	 */
  	return;
      }
      shutdown_pending = 1;
  }
  
  /* do a graceful restart if graceful == 1 */
  void ap_start_restart(int graceful)
  {
  
      if (restart_pending == 1) {
  	/* Probably not an error - don't bother reporting it */
  	return;
      }
      restart_pending = 1;
      is_graceful = graceful;
  }
  
  static void sig_term(int sig)
  {
      ap_start_shutdown();
  }
  
  static void restart(int sig)
  {
  #ifndef WIN32
      ap_start_restart(sig == SIGWINCH);
  #else
      ap_start_restart(1);
  #endif
  }
  
  static void set_signals(void)
  {
  #ifndef NO_USE_SIGACTION
      struct sigaction sa;
  
      sigemptyset(&sa.sa_mask);
      sa.sa_flags = 0;
  
      if (!one_process) {
  	sa.sa_handler = sig_coredump;
  #if defined(SA_ONESHOT)
  	sa.sa_flags = SA_ONESHOT;
  #elif defined(SA_RESETHAND)
  	sa.sa_flags = SA_RESETHAND;
  #endif
  	if (sigaction(SIGSEGV, &sa, NULL) < 0)
  	    ap_log_error(APLOG_MARK, APLOG_WARNING, server_conf, "sigaction(SIGSEGV)");
  #ifdef SIGBUS
  	if (sigaction(SIGBUS, &sa, NULL) < 0)
  	    ap_log_error(APLOG_MARK, APLOG_WARNING, server_conf, "sigaction(SIGBUS)");
  #endif
  #ifdef SIGABORT
  	if (sigaction(SIGABORT, &sa, NULL) < 0)
  	    ap_log_error(APLOG_MARK, APLOG_WARNING, server_conf, "sigaction(SIGABORT)");
  #endif
  #ifdef SIGABRT
  	if (sigaction(SIGABRT, &sa, NULL) < 0)
  	    ap_log_error(APLOG_MARK, APLOG_WARNING, server_conf, "sigaction(SIGABRT)");
  #endif
  #ifdef SIGILL
  	if (sigaction(SIGILL, &sa, NULL) < 0)
  	    ap_log_error(APLOG_MARK, APLOG_WARNING, server_conf, "sigaction(SIGILL)");
  #endif
  	sa.sa_flags = 0;
      }
      sa.sa_handler = sig_term;
      if (sigaction(SIGTERM, &sa, NULL) < 0)
  	ap_log_error(APLOG_MARK, APLOG_WARNING, server_conf, "sigaction(SIGTERM)");
  #ifdef SIGINT
      if (sigaction(SIGINT, &sa, NULL) < 0)
          ap_log_error(APLOG_MARK, APLOG_WARNING, server_conf, "sigaction(SIGINT)");
  #endif
  #ifdef SIGXCPU
      sa.sa_handler = SIG_DFL;
      if (sigaction(SIGXCPU, &sa, NULL) < 0)
  	ap_log_error(APLOG_MARK, APLOG_WARNING, server_conf, "sigaction(SIGXCPU)");
  #endif
  #ifdef SIGXFSZ
      sa.sa_handler = SIG_DFL;
      if (sigaction(SIGXFSZ, &sa, NULL) < 0)
  	ap_log_error(APLOG_MARK, APLOG_WARNING, server_conf, "sigaction(SIGXFSZ)");
  #endif
  #ifdef SIGPIPE
      sa.sa_handler = SIG_IGN;
      if (sigaction(SIGPIPE, &sa, NULL) < 0)
  	ap_log_error(APLOG_MARK, APLOG_WARNING, server_conf, "sigaction(SIGPIPE)");
  #endif
  
      /* we want to ignore HUPs and WINCH while we're busy processing one */
      sigaddset(&sa.sa_mask, SIGHUP);
      sigaddset(&sa.sa_mask, SIGWINCH);
      sa.sa_handler = restart;
      if (sigaction(SIGHUP, &sa, NULL) < 0)
  	ap_log_error(APLOG_MARK, APLOG_WARNING, server_conf, "sigaction(SIGHUP)");
      if (sigaction(SIGWINCH, &sa, NULL) < 0)
  	ap_log_error(APLOG_MARK, APLOG_WARNING, server_conf, "sigaction(SIGWINCH)");
  #else
      if (!one_process) {
  	signal(SIGSEGV, sig_coredump);
  #ifdef SIGBUS
  	signal(SIGBUS, sig_coredump);
  #endif /* SIGBUS */
  #ifdef SIGABORT
  	signal(SIGABORT, sig_coredump);
  #endif /* SIGABORT */
  #ifdef SIGABRT
  	signal(SIGABRT, sig_coredump);
  #endif /* SIGABRT */
  #ifdef SIGILL
  	signal(SIGILL, sig_coredump);
  #endif /* SIGILL */
  #ifdef SIGXCPU
  	signal(SIGXCPU, SIG_DFL);
  #endif /* SIGXCPU */
  #ifdef SIGXFSZ
  	signal(SIGXFSZ, SIG_DFL);
  #endif /* SIGXFSZ */
      }
  
      signal(SIGTERM, sig_term);
  #ifdef SIGHUP
      signal(SIGHUP, restart);
  #endif /* SIGHUP */
  #ifdef SIGWINCH
      signal(SIGWINCH, restart);
  #endif /* SIGWINCH */
  #ifdef SIGPIPE
      signal(SIGPIPE, SIG_IGN);
  #endif /* SIGPIPE */
  
  #endif
  }
   
  static int setup_listeners(pool *pconf, server_rec *s)
  {
      ap_listen_rec *lr;
      int num_listeners = 0;
  
      if (ap_listen_open(pconf, s->port)) {
         return 0;
      }
      for (lr = ap_listeners; lr; lr = lr->next) {
          num_listeners++;
      }
      return num_listeners;
  }
  
  /*****************************************************************
   * Here follows a long bunch of generic server bookkeeping stuff...
   */
  
  #if defined(TCP_NODELAY) && !defined(MPE) && !defined(TPF)
  static void sock_disable_nagle(int s) /* ZZZ abstract */
  {
      /* The Nagle algorithm says that we should delay sending partial
       * packets in hopes of getting more data.  We don't want to do
       * this; we are not telnet.  There are bad interactions between
       * persistent connections and Nagle's algorithm that have very severe
       * performance penalties.  (Failing to disable Nagle is not much of a
       * problem with simple HTTP.)
       *
       * In spite of these problems, failure here is not a shooting offense.
       */
      int just_say_no = 1;
  
      if (setsockopt(s, IPPROTO_TCP, TCP_NODELAY, (char *) &just_say_no,
  		   sizeof(int)) < 0) {
  	ap_log_error(APLOG_MARK, APLOG_WARNING, server_conf,
  		    "setsockopt: (TCP_NODELAY)");
      }
  }
  
  #else
  #define sock_disable_nagle(s)	/* NOOP */
  #endif
  
  int ap_graceful_stop_signalled(void)
  {
      /* XXX - Does this really work? - Manoj */
      return is_graceful;
  }
  
  /*****************************************************************
   * Child process main loop.
   */
  
  static void process_socket(pool *p, struct sockaddr *sa_client, int csd, int my_child_num, int my_thread_num)
  {
      struct sockaddr sa_server; /* ZZZZ */
      size_t len = sizeof(struct sockaddr);
      BUFF *conn_io;
      conn_rec *current_conn;
      ap_iol *iol;
  
      if (getsockname(csd, &sa_server, &len) < 0) { 
  	ap_log_error(APLOG_MARK, APLOG_ERR, server_conf, "getsockname");
  	close(csd);
  	return;
      }
  
      sock_disable_nagle(csd);
  
      iol = unix_attach_socket(csd);
      if (iol == NULL) {
          if (errno == EBADF) {
              ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_WARNING, NULL,
                  "filedescriptor (%u) larger than FD_SETSIZE (%u) "
                  "found, you probably need to rebuild Apache with a "
                  "larger FD_SETSIZE", csd, FD_SETSIZE);
          }
          else {
              ap_log_error(APLOG_MARK, APLOG_WARNING, NULL,
                  "error attaching to socket");
          }
          close(csd);
  	return;
      }
  
      conn_io = ap_bcreate(p, B_RDWR);
      ap_bpush_iol(conn_io, iol);
  
      current_conn = ap_new_connection(p, server_conf, conn_io,
                                    (const struct sockaddr_in *) sa_client, 
                                    (const struct sockaddr_in *) &sa_server, 
                                    my_child_num, my_thread_num);
  
      ap_process_connection(current_conn);
  }
  
  static void * worker_thread(void * dummy)
  {
      proc_info * ti = dummy;
      int process_slot = ti->pid;
      int thread_slot = ti->tid;
      pool *tpool = ti->tpool;
      struct sockaddr sa_client;
      int csd = -1;
      pool *ptrans;		/* Pool for per-transaction stuff */
      int sd = -1;
      int srv;
      int ret;
      char pipe_read_char;
      int curr_pollfd, last_pollfd = 0;
      size_t len = sizeof(struct sockaddr);
  
      free(ti);
  
      ptrans = ap_make_sub_pool(tpool);
  
      pthread_mutex_lock(&worker_thread_count_mutex);
      worker_thread_count++;
      pthread_mutex_unlock(&worker_thread_count_mutex);
  
      /* TODO: Switch to a system where threads reuse the results from earlier
         poll calls - manoj */
      while (!workers_may_exit) {
          workers_may_exit |= (ap_max_requests_per_child != 0) && (requests_this_child <= 0);
          if (workers_may_exit) break;
  
          SAFE_ACCEPT(intra_mutex_on(0));
          if (workers_may_exit) {
              SAFE_ACCEPT(intra_mutex_off(0));
              break;
          }
          SAFE_ACCEPT(accept_mutex_on(0));
          while (!workers_may_exit) {
              srv = poll(listenfds, num_listenfds + 1, -1);
              if (srv < 0) {
                  if (errno == EINTR) {
                      continue;
                  }
  
                  /* poll() will only return errors in catastrophic
                   * circumstances. Let's try exiting gracefully, for now. */
                  ap_log_error(APLOG_MARK, APLOG_ERR, (const server_rec *)
                               ap_get_server_conf(), "poll: (listen)");
                  workers_may_exit = 1;
              }
  
              if (workers_may_exit) break;
  
              if (listenfds[0].revents & POLLIN) {
                  /* A process got a signal on the shutdown pipe. Check if we're
                   * the lucky process to die. */
                  pthread_mutex_lock(&pipe_of_death_mutex);
                  if (!workers_may_exit) {
                      ret = read(listenfds[0].fd, &pipe_read_char, 1);
                      if (ret == -1 && errno == EAGAIN) {
                          /* It lost the lottery. It must continue to suffer
                           * through a life of servitude. */
                          pthread_mutex_unlock(&pipe_of_death_mutex);
                          continue;
                      }
                      else {
                          /* It won the lottery (or something else is very
                           * wrong). Embrace death with open arms. */
                          workers_may_exit = 1;
                          pthread_mutex_unlock(&pipe_of_death_mutex);
                          break;
                      }
                  }
                  pthread_mutex_unlock(&pipe_of_death_mutex);
              }
  
              if (num_listenfds == 1) {
                  sd = ap_listeners->fd;
                  goto got_fd;
              }
              else {
                  /* find a listener */
                  curr_pollfd = last_pollfd;
                  do {
                      curr_pollfd++;
                      if (curr_pollfd > num_listenfds) {
                          curr_pollfd = 1;
                      }
                      /* XXX: Should we check for POLLERR? */
                      if (listenfds[curr_pollfd].revents & POLLIN) {
                          last_pollfd = curr_pollfd;
                          sd = listenfds[curr_pollfd].fd;
                          goto got_fd;
                      }
                  } while (curr_pollfd != last_pollfd);
              }
          }
      got_fd:
          SAFE_ACCEPT(accept_mutex_off(0));
          SAFE_ACCEPT(intra_mutex_off(0));
          if (workers_may_exit) break;
          csd = ap_accept(sd, &sa_client, &len);
          process_socket(ptrans, &sa_client, csd, process_slot, thread_slot);
          ap_clear_pool(ptrans);
          requests_this_child--;
      }
  
      ap_destroy_pool(tpool);
      pthread_mutex_lock(&worker_thread_count_mutex);
      worker_thread_count--;
      if (worker_thread_count == 0) {
          /* All the threads have exited, now finish the shutdown process
           * by signalling the sigwait thread */
          kill(my_pid, SIGTERM);
      }
      pthread_mutex_unlock(&worker_thread_count_mutex);
  
      return NULL;
  }
  
  static void child_main(int child_num_arg)
  {
      sigset_t sig_mask;
      int signal_received;
      pthread_t thread;
      pthread_attr_t thread_attr;
      int i;
      int my_child_num = child_num_arg;
      proc_info *my_info = NULL;
      ap_listen_rec *lr;
  
      my_pid = getpid();
      pchild = ap_make_sub_pool(pconf);
  
      /*stuff to do before we switch id's, so we have permissions.*/
  
      SAFE_ACCEPT(intra_mutex_init(pchild, 1));
      SAFE_ACCEPT(accept_mutex_child_init(pchild));
  
      if (unixd_setup_child()) {
  	clean_child_exit(APEXIT_CHILDFATAL);
      }
  
      ap_child_init_hook(pchild, server_conf);
  
      /*done with init critical section */
  
      /* All threads should mask signals out, accoring to sigwait(2) man page */
      sigemptyset(&sig_mask);
  
      if (pthread_sigmask(SIG_SETMASK, &sig_mask, NULL) != 0) {
          ap_log_error(APLOG_MARK, APLOG_ALERT, server_conf, "pthread_sigmask");
      }
  
      requests_this_child = ap_max_requests_per_child;
      
      /* Set up the pollfd array */
      listenfds = ap_palloc(pchild, sizeof(struct pollfd) * (num_listenfds + 1));
      listenfds[0].fd = pipe_of_death[0];
      listenfds[0].events = POLLIN;
      listenfds[0].revents = 0;
      for (lr = ap_listeners, i = 1; i <= num_listenfds; lr = lr->next, ++i) {
          listenfds[i].fd = lr->fd;
          listenfds[i].events = POLLIN; /* should we add POLLPRI ?*/
          listenfds[i].revents = 0;
      }
  
      /* Setup worker threads */
  
      worker_thread_count = 0;
      pthread_mutex_init(&worker_thread_count_mutex, NULL);
      pthread_mutex_init(&pipe_of_death_mutex, NULL);
      pthread_attr_init(&thread_attr);
      pthread_attr_setdetachstate(&thread_attr, PTHREAD_CREATE_DETACHED);
      for (i=0; i < ap_threads_per_child; i++) {
  
  	my_info = (proc_info *)malloc(sizeof(proc_info));
          if (my_info == NULL) {
              ap_log_error(APLOG_MARK, APLOG_ALERT, server_conf,
  		         "malloc: out of memory");
              clean_child_exit(APEXIT_CHILDFATAL);
          }
  	my_info->pid = my_child_num;
          my_info->tid = i;
  	my_info->sd = 0;
  	my_info->tpool = ap_make_sub_pool(pchild);
  	
  	/* We are creating threads right now */
  	if (pthread_create(&thread, &thread_attr, worker_thread, my_info)) {
  	    ap_log_error(APLOG_MARK, APLOG_ALERT, server_conf,
  			 "pthread_create: unable to create worker thread");
              /* In case system resources are maxxed out, we don't want
                 Apache running away with the CPU trying to fork over and
                 over and over again if we exit. */
              sleep(10);
  	    clean_child_exit(APEXIT_CHILDFATAL);
  	}
  
  	/* We let each thread update it's own scoreboard entry.  This is done
  	 * because it let's us deal with tid better.
  	 */
      }
  
      pthread_attr_destroy(&thread_attr);
  
      /* This thread will be the one responsible for handling signals */
      sigemptyset(&sig_mask);
      sigaddset(&sig_mask, SIGTERM);
      sigaddset(&sig_mask, SIGINT);
      sigwait(&sig_mask, &signal_received);
      switch (signal_received) {
          case SIGTERM:
          case SIGINT:
              just_die(signal_received);
              break;
          default:
              ap_log_error(APLOG_MARK, APLOG_ALERT, server_conf,
              "received impossible signal: %d", signal_received);
              just_die(SIGTERM);
      }
  }
  
  static int make_child(server_rec *s, int slot, time_t now) /* ZZZ */
  {
      int pid;
  
      (void) ap_update_child_status(slot, SERVER_ALIVE);
  
      if (slot + 1 > max_daemons_limit) {
          max_daemons_limit = slot + 1;
      }
  
      if (one_process) {
  	set_signals();
          ap_scoreboard_image[slot].pid = getpid();
  	child_main(slot);
      }
  
      if ((pid = fork()) == -1) {
          ap_log_error(APLOG_MARK, APLOG_ERR, s, "fork: Unable to fork new process");
  	/* In case system resources are maxxed out, we don't want
  	   Apache running away with the CPU trying to fork over and
  	   over and over again. */
  	sleep(10);
  
  	return -1;
      }
  
      if (!pid) {
  #ifdef AIX_BIND_PROCESSOR
        /* By default, AIX binds to a single processor.  This bit unbinds
  	 children which will then bind to another CPU.
        */
  #include <sys/processor.h>
          int status = bindprocessor(BINDPROCESS, (int)getpid(),
  			       PROCESSOR_CLASS_ANY);
  	if (status != OK)
  	    ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_WARNING, server_conf,
  			 "processor unbind failed %d", status);
  #endif
  
          RAISE_SIGSTOP(MAKE_CHILD);
  
  	/* XXX - For an unthreaded server, a signal handler will be necessary
          signal(SIGTERM, just_die);
  	*/
          child_main(slot);
  
  	return 0;
      }
      /* else */
      ap_scoreboard_image[slot].pid = pid;
      return 0;
  }
  
  /* start up a bunch of children */
  static void startup_children(int number_to_start)
  {
      int i;
  
      for (i = 0; number_to_start && i < ap_num_daemons; ++i) {
  	if (ap_scoreboard_image[i].pid != 0) {
  	    continue;
  	}
  	if (make_child(server_conf, i, 0) < 0) {
  	    break;
  	}
  	--number_to_start;
      }
  }
  
  
  /*
   * spawn_rate is the number of children that will be spawned on the
   * next maintenance cycle if there aren't enough servers.  It is
   * doubled up to MAX_SPAWN_RATE, and reset only when a cycle goes by
   * without the need to spawn.
   */
  static int spawn_rate = 1;
  #ifndef MAX_SPAWN_RATE
  #define MAX_SPAWN_RATE	(32)
  #endif
  static int hold_off_on_exponential_spawning;
  
  static void perform_child_maintenance(void)
  {
      int i;
      time_t now = 0;
      int free_length;
      int free_slots[MAX_SPAWN_RATE];
      int last_non_dead = -1;
  
      /* initialize the free_list */
      free_length = 0;
      
      ap_check_signals();
      
      for (i = 0; i < ap_num_daemons; ++i) {
          unsigned char status = ap_scoreboard_image[i].status;
  
          if (status == SERVER_DEAD) {
              free_slots[free_length] = i;
              ++free_length;
          } else {
              last_non_dead = i;
          }
  
  	if (free_length >= spawn_rate) {
  	    break;
  	}
      }
      max_daemons_limit = last_non_dead + 1;
  
      if (free_length > 0) {
  	for (i = 0; i < free_length; ++i) {
  	    make_child(server_conf, free_slots[i], now);
  	}
  	/* the next time around we want to spawn twice as many if this
  	 * wasn't good enough, but not if we've just done a graceful
  	 */
  	if (hold_off_on_exponential_spawning) {
  	    --hold_off_on_exponential_spawning;
  	}
  	else if (spawn_rate < MAX_SPAWN_RATE) {
  	    spawn_rate *= 2;
  	}
      }
      else {
          spawn_rate = 1;
      }
  }
  
  static void server_main_loop(int remaining_children_to_start)
  {
      int child_slot;
      ap_wait_t status;
      int pid;
  
      while (!restart_pending && !shutdown_pending) {
          pid = wait_or_timeout(&status);
          
          if (pid >= 0) {
              child_slot = find_child_by_pid(pid);
              if (child_slot >= 0) {
                  ap_update_child_status(child_slot, SERVER_DEAD);
                  
  		if (remaining_children_to_start
  		    && child_slot < ap_num_daemons) {
  		    /* we're still doing a 1-for-1 replacement of dead
                       * children with new children
                       */
                      /* ZZZ abstract out for AP funcs. */
  		    make_child(server_conf, child_slot, time(NULL));
  		    --remaining_children_to_start;
  		}
  #ifdef HAS_OTHER_CHILD
  	    }
  	    else if (reap_other_child(pid, status) == 0) {
  		/* handled */
  #endif
  	    }
  	    else if (is_graceful) {
  		/* Great, we've probably just lost a slot in the
  		    * scoreboard.  Somehow we don't know about this
  		    * child.
  		    */
  		ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_WARNING, server_conf,
  			    "long lost child came home! (pid %d)", pid);
  	    }
  	    /* Don't perform idle maintenance when a child dies,
               * only do it when there's a timeout.  Remember only a
               * finite number of children can die, and it's pretty
               * pathological for a lot to die suddenly.
               */
  	    continue;
  	}
  	else if (remaining_children_to_start) {
  	    /* we hit a 1 second timeout in which none of the previous
  	     * generation of children needed to be reaped... so assume
  	     * they're all done, and pick up the slack if any is left.
  	     */
  	    startup_children(remaining_children_to_start);
  	    remaining_children_to_start = 0;
  	    /* In any event we really shouldn't do the code below because
  	     * few of the servers we just started are in the IDLE state
  	     * yet, so we'd mistakenly create an extra server.
  	     */
  	    continue;
  	}
  
  	perform_child_maintenance();
      }
  }
  
  int ap_mpm_run(pool *_pconf, pool *plog, server_rec *s)
  {
      int remaining_children_to_start;
  
      pconf = _pconf;
      server_conf = s;
      if (pipe(pipe_of_death) == -1) {
          ap_log_error(APLOG_MARK, APLOG_ERR,
                       (const server_rec*) server_conf,
                       "pipe: (pipe_of_death)");
          exit(1);
      }
      ap_note_cleanups_for_fd(pconf, pipe_of_death[0]);
      ap_note_cleanups_for_fd(pconf, pipe_of_death[1]);
      if (fcntl(pipe_of_death[0], F_SETFD, O_NONBLOCK) == -1) {
          ap_log_error(APLOG_MARK, APLOG_ERR,
                       (const server_rec*) server_conf,
                       "fcntl: O_NONBLOCKing (pipe_of_death)");
          exit(1);
      }
      server_conf = s;
      if ((num_listenfds = setup_listeners(pconf, server_conf)) < 1) {
          /* XXX: hey, what's the right way for the mpm to indicate a fatal error? */
          ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_ALERT, s,
              "no listening sockets available, shutting down");
          return 1;
      }
      ap_clear_pool(plog);
      ap_open_logs(server_conf, plog);
      ap_log_pid(pconf, ap_pid_fname);
      SAFE_ACCEPT(accept_mutex_init(pconf, 1));
      if (!is_graceful) {
          reinit_scoreboard(pconf);
      }
  
      set_signals();
  
      /* If we're doing a graceful_restart then we're going to see a lot
       * of children exiting immediately when we get into the main loop
       * below (because we just sent them SIGWINCH).  This happens pretty
       * rapidly... and for each one that exits we'll start a new one until
       * we reach at least daemons_min_free.  But we may be permitted to
       * start more than that, so we'll just keep track of how many we're
       * supposed to start up without the 1 second penalty between each fork.
       */
      remaining_children_to_start = ap_num_daemons;
      if (!is_graceful) {
  	startup_children(remaining_children_to_start);
  	remaining_children_to_start = 0;
      }
      else {
  	/* give the system some time to recover before kicking into
  	    * exponential mode */
  	hold_off_on_exponential_spawning = 10;
      }
  
      ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_NOTICE, server_conf,
  		"%s configured -- resuming normal operations",
  		ap_get_server_version());
      ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_INFO, server_conf,
  		"Server built: %s", ap_get_server_built());
      restart_pending = shutdown_pending = 0;
  
      server_main_loop(remaining_children_to_start);
  
      if (shutdown_pending) {
          /* Time to gracefully shut down:
           * Kill child processes, tell them to call child_exit, etc...
           */
          if (ap_killpg(getpgrp(), SIGTERM) < 0) {
              ap_log_error(APLOG_MARK, APLOG_WARNING, server_conf, "killpg SIGTERM");
          }
          reclaim_child_processes(1);		/* Start with SIGTERM */
      
          /* cleanup pid file on normal shutdown */
          {
              const char *pidfile = NULL;
              pidfile = ap_server_root_relative (pconf, ap_pid_fname);
              if ( pidfile != NULL && unlink(pidfile) == 0)
                  ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_INFO,
              		 server_conf,
              		 "removed PID file %s (pid=%ld)",
              		 pidfile, (long)getpid());
          }
      
          ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_NOTICE, server_conf,
              "caught SIGTERM, shutting down");
      
  	return 1;
      }
  
      /* we've been told to restart */
      signal(SIGHUP, SIG_IGN);
  
      if (one_process) {
  	/* not worth thinking about */
  	return 1;
      }
  
      if (is_graceful) {
  	int i;
          char char_of_death = '!';
  
  	ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_NOTICE, server_conf,
  		    "SIGWINCH received.  Doing graceful restart");
  
  	/* This is mostly for debugging... so that we know what is still
           * gracefully dealing with existing request.
           */
  	
  	for (i = 0; i < ap_num_daemons; ++i) {
  	    if (ap_scoreboard_image[i].status != SERVER_DEAD) {
  	        ap_scoreboard_image[i].status = SERVER_DYING;
  	    } 
  	}
  	/* kill off the idle ones */
          for (i = 0; i < ap_num_daemons; ++i) {
              if (write(pipe_of_death[1], &char_of_death, 1) == -1) {
                  ap_log_error(APLOG_MARK, APLOG_WARNING, server_conf, "write pipe_of_death");
              }
          }
      }
      else {
        /* Kill 'em all.  Since the child acts the same on the parents SIGTERM 
         * and a SIGHUP, we may as well use the same signal, because some user
         * pthreads are stealing signals from us left and right.
         */
  	if (ap_killpg(getpgrp(), SIGTERM) < 0) {
  	    ap_log_error(APLOG_MARK, APLOG_WARNING, server_conf, "killpg SIGTERM");
  	}
          reclaim_child_processes(1);		/* Start with SIGTERM */
  	ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_NOTICE, server_conf,
  		    "SIGHUP received.  Attempting to restart");
      }
      if (!is_graceful) {
          ap_restart_time = time(NULL); /* ZZZZZ */
      }
      return 0;
  }
  
  static void dexter_pre_command_line(pool *pcommands)
  {
      INIT_SIGLIST()
      one_process = 0;
  }
  
  static void dexter_pre_config(pool *pconf, pool *plog, pool *ptemp)
  {
      static int restart_num = 0;
  
      one_process = ap_exists_config_define("ONE_PROCESS");
  
      /* sigh, want this only the second time around */
      if (restart_num++ == 1) {
  	is_graceful = 0;
  
  	if (!one_process) {
  	    unixd_detach();
  	}
  
  	my_pid = getpid();
      }
  
      unixd_pre_config();
      ap_listen_pre_config();
      ap_num_daemons = HARD_SERVER_LIMIT;
      ap_threads_per_child = DEFAULT_THREADS_PER_CHILD;
      ap_pid_fname = DEFAULT_PIDLOG;
      ap_lock_fname = DEFAULT_LOCKFILE;
      ap_max_requests_per_child = DEFAULT_MAX_REQUESTS_PER_CHILD;
      ap_extended_status = 0;
  
      ap_cpystrn(ap_coredump_dir, ap_server_root, sizeof(ap_coredump_dir));
  }
  
  
  static const char *set_pidfile(cmd_parms *cmd, void *dummy, char *arg) 
  {
      const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
      if (err != NULL) {
          return err;
      }
  
      if (cmd->server->is_virtual) {
  	return "PidFile directive not allowed in <VirtualHost>";
      }
      ap_pid_fname = arg;
      return NULL;
  }
  
  static const char *set_lockfile(cmd_parms *cmd, void *dummy, char *arg) 
  {
      const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
      if (err != NULL) {
          return err;
      }
  
      ap_lock_fname = arg;
      return NULL;
  }
  static const char *set_num_daemons (cmd_parms *cmd, void *dummy, char *arg) 
  {
      const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
      if (err != NULL) {
          return err;
      }
  
      ap_num_daemons = atoi(arg);
      if (ap_num_daemons > HARD_SERVER_LIMIT) {
         fprintf(stderr, "WARNING: MaxClients of %d exceeds compile time limit "
             "of %d servers,\n", ap_num_daemons, HARD_SERVER_LIMIT);
         fprintf(stderr, " lowering MaxClients to %d.  To increase, please "
             "see the\n", HARD_SERVER_LIMIT);
         fprintf(stderr, " HARD_SERVER_LIMIT define in src/include/httpd.h.\n");
         ap_num_daemons = HARD_SERVER_LIMIT;
      } 
      else if (ap_num_daemons < 1) {
  	fprintf(stderr, "WARNING: Require MaxClients > 0, setting to 1\n");
  	ap_num_daemons = 1;
      }
      return NULL;
  }
  
  static const char *set_threads_per_child (cmd_parms *cmd, void *dummy, char *arg) 
  {
      const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
      if (err != NULL) {
          return err;
      }
  
      ap_threads_per_child = atoi(arg);
      if (ap_threads_per_child > HARD_THREAD_LIMIT) {
          fprintf(stderr, "WARNING: ThreadsPerChild of %d exceeds compile time"
                  "limit of %d threads,\n", ap_threads_per_child,
                  HARD_THREAD_LIMIT);
          fprintf(stderr, " lowering ThreadsPerChild to %d. To increase, please"
                  "see the\n", HARD_THREAD_LIMIT);
          fprintf(stderr, " HARD_THREAD_LIMIT define in src/include/httpd.h.\n");
      }
      else if (ap_threads_per_child < 1) {
  	fprintf(stderr, "WARNING: Require ThreadsPerChild > 0, setting to 1\n");
  	ap_threads_per_child = 1;
      }
      return NULL;
  }
  
  static const char *set_max_requests(cmd_parms *cmd, void *dummy, char *arg) 
  {
      const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
      if (err != NULL) {
          return err;
      }
  
      ap_max_requests_per_child = atoi(arg);
  
      return NULL;
  }
  
  static const char *set_coredumpdir (cmd_parms *cmd, void *dummy, char *arg) 
  {
      struct stat finfo;
      const char *fname;
      const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
      if (err != NULL) {
          return err;
      }
  
      fname = ap_server_root_relative(cmd->pool, arg);
      /* ZZZ change this to the AP func FileInfo*/
      if ((stat(fname, &finfo) == -1) || !S_ISDIR(finfo.st_mode)) {
  	return ap_pstrcat(cmd->pool, "CoreDumpDirectory ", fname, 
  			  " does not exist or is not a directory", NULL);
      }
      ap_cpystrn(ap_coredump_dir, fname, sizeof(ap_coredump_dir));
      return NULL;
  }
  
  struct ap_thread_mutex {
      pthread_mutex_t mutex;
  };
  
  API_EXPORT(ap_thread_mutex *) ap_thread_mutex_new(void)
  {
      ap_thread_mutex *mtx;
  
      mtx = malloc(sizeof(ap_thread_mutex));
      pthread_mutex_init(&(mtx->mutex), NULL);
      return mtx;
  }
  
  API_EXPORT(void) ap_thread_mutex_lock(ap_thread_mutex *mtx)
  {
      /* Ignoring error conditions here. :( */
      pthread_mutex_lock(&(mtx->mutex));
  }
  
  API_EXPORT(void) ap_thread_mutex_unlock(ap_thread_mutex *mtx)
  {
      /* Here too. */
      pthread_mutex_unlock(&(mtx->mutex));
  }
  
  API_EXPORT(void) ap_thread_mutex_destroy(ap_thread_mutex *mtx)
  {
      /* Here too. */
      pthread_mutex_destroy(&(mtx->mutex));
      free(mtx);
  }
  
  
  static const command_rec dexter_cmds[] = {
  UNIX_DAEMON_COMMANDS
  LISTEN_COMMANDS
  { "PidFile", set_pidfile, NULL, RSRC_CONF, TAKE1,
      "A file for logging the server process ID"},
  { "LockFile", set_lockfile, NULL, RSRC_CONF, TAKE1,
      "The lockfile used when Apache needs to lock the accept() call"},
  { "NumServers", set_num_daemons, NULL, RSRC_CONF, TAKE1,
    "Number of children alive at the same time" },
  { "ThreadsPerChild", set_threads_per_child, NULL, RSRC_CONF, TAKE1,
    "Number of threads each child creates" },
  { "MaxRequestsPerChild", set_max_requests, NULL, RSRC_CONF, TAKE1,
    "Maximum number of requests a particular child serves before dying." },
  { "CoreDumpDirectory", set_coredumpdir, NULL, RSRC_CONF, TAKE1,
    "The location of the directory Apache changes to before dumping core" },
  { NULL }
  };
  
  module MODULE_VAR_EXPORT mpm_dexter_module = {
      STANDARD20_MODULE_STUFF,
      dexter_pre_command_line,	/* pre_command_line */
      dexter_pre_config,		/* pre_config */
      NULL,                       /* post_config */
      NULL,			/* open_logs */
      NULL, 			/* child_init */
      NULL,			/* create per-directory config structure */
      NULL,			/* merge per-directory config structures */
      NULL,			/* create per-server config structure */
      NULL,			/* merge per-server config structures */
      dexter_cmds,		/* command table */
      NULL,			/* handlers */
      NULL,			/* check auth */
      NULL,			/* check access */
      NULL,			/* type_checker */
      NULL,			/* pre-run fixups */
      NULL			/* register hooks */
  };
  
  /* force Expat to be linked into the server executable */
  #if defined(USE_EXPAT) && !defined(SHARED_CORE_BOOTSTRAP)
  #include "xmlparse.h"
  const XML_LChar *suck_in_expat(void);
  const XML_LChar *suck_in_expat(void)
  {
      return XML_ErrorString(XML_ERROR_NONE);
  }
  #endif /* USE_EXPAT */
  
  
  
  1.1                  apache-2.0/mpm/src/modules/mpm/dexter/dexter.h
  
  Index: dexter.h
  ===================================================================
  /* ====================================================================
   * Copyright (c) 1995-1999 The Apache Group.  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. All advertising materials mentioning features or use of this 
   *    software must display the following acknowledgment: 
   *    "This product includes software developed by the Apache Group 
   *    for use in the Apache HTTP server project (http://www.apache.org/)." 
   * 
   * 4. The names "Apache Server" and "Apache Group" must not be used to 
   *    endorse or promote products derived from this software without 
   *    prior written permission. For written permission, please contact 
   *    apache@apache.org. 
   * 
   * 5. Products derived from this software may not be called "Apache" 
   *    nor may "Apache" appear in their names without prior written 
   *    permission of the Apache Group. 
   * 
   * 6. Redistributions of any form whatsoever must retain the following 
   *    acknowledgment: 
   *    "This product includes software developed by the Apache Group 
   *    for use in the Apache HTTP server project (http://www.apache.org/)." 
   * 
   * THIS SOFTWARE IS PROVIDED BY THE APACHE GROUP ``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 GROUP 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 Group and was originally based 
   * on public domain software written at the National Center for 
   * Supercomputing Applications, University of Illinois, Urbana-Champaign. 
   * For more information on the Apache Group and the Apache HTTP server 
   * project, please see <http://www.apache.org/>. 
   * 
   */ 
  
  #ifndef APACHE_MPM_MPMT_PTHREAD_H
  #define APACHE_MPM_MPMT_PTHREAD_H
  
  extern int ap_threads_per_child;
  extern int max_daemons_limit;
  extern int ap_max_requests_per_child;
  extern int ap_pipe_of_death[2];
  extern void clean_child_exit(int);
  extern int ap_extended_status;
  extern void clean_child_exit(int);
  
  #endif /* APACHE_MPM_MPMT_PTHREAD_H */
  
  
  
  1.1                  apache-2.0/mpm/src/modules/mpm/dexter/mpm_default.h
  
  Index: mpm_default.h
  ===================================================================
  /* ====================================================================
   * Copyright (c) 1995-1999 The Apache Group.  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. All advertising materials mentioning features or use of this 
   *    software must display the following acknowledgment: 
   *    "This product includes software developed by the Apache Group 
   *    for use in the Apache HTTP server project (http://www.apache.org/)." 
   * 
   * 4. The names "Apache Server" and "Apache Group" must not be used to 
   *    endorse or promote products derived from this software without 
   *    prior written permission. For written permission, please contact 
   *    apache@apache.org. 
   * 
   * 5. Products derived from this software may not be called "Apache" 
   *    nor may "Apache" appear in their names without prior written 
   *    permission of the Apache Group. 
   * 
   * 6. Redistributions of any form whatsoever must retain the following 
   *    acknowledgment: 
   *    "This product includes software developed by the Apache Group 
   *    for use in the Apache HTTP server project (http://www.apache.org/)." 
   * 
   * THIS SOFTWARE IS PROVIDED BY THE APACHE GROUP ``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 GROUP 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 Group and was originally based 
   * on public domain software written at the National Center for 
   * Supercomputing Applications, University of Illinois, Urbana-Champaign. 
   * For more information on the Apache Group and the Apache HTTP server 
   * project, please see <http://www.apache.org/>. 
   * 
   */ 
  
  #ifndef APACHE_MPM_DEFAULT_H
  #define APACHE_MPM_DEFAULT_H
  
  /* Number of servers to spawn off by default --- also, if fewer than
   * this free when the caretaker checks, it will spawn more.
   */
  #ifndef DEFAULT_START_DAEMON
  #define DEFAULT_START_DAEMON 5
  #endif
  
  /* Maximum number of *free* server processes --- more than this, and
   * they will die off.
   */
  
  #ifndef DEFAULT_MAX_FREE_DAEMON
  #define DEFAULT_MAX_FREE_DAEMON 10
  #endif
  
  /* Minimum --- fewer than this, and more will be created */
  
  #ifndef DEFAULT_MIN_FREE_DAEMON
  #define DEFAULT_MIN_FREE_DAEMON 5
  #endif
  
  /* Limit on the total --- clients will be locked out if more servers than
   * this are needed.  It is intended solely to keep the server from crashing
   * when things get out of hand.
   *
   * We keep a hard maximum number of servers, for two reasons --- first off,
   * in case something goes seriously wrong, we want to stop the fork bomb
   * short of actually crashing the machine we're running on by filling some
   * kernel table.  Secondly, it keeps the size of the scoreboard file small
   * enough that we can read the whole thing without worrying too much about
   * the overhead.
   */
  #ifndef HARD_SERVER_LIMIT
  #define HARD_SERVER_LIMIT 8 
  #endif
  
  /* Limit on the threads per process.  Clients will be locked out if more than
   * this  * HARD_SERVER_LIMIT are needed.
   *
   * We keep this for one reason it keeps the size of the scoreboard file small
   * enough that we can read the whole thing without worrying too much about
   * the overhead.
   */
  #ifndef HARD_THREAD_LIMIT
  #define HARD_THREAD_LIMIT 64 
  #endif
  
  #ifndef DEFAULT_THREADS_PER_CHILD
  #define DEFAULT_THREADS_PER_CHILD 50
  #endif
  
  #endif /* AP_MPM_DEFAULT_H */
  
  
  
  1.1                  apache-2.0/mpm/src/modules/mpm/dexter/scoreboard.c
  
  Index: scoreboard.c
  ===================================================================
  #include "httpd.h"
  #include "http_log.h"
  #include "http_main.h"
  #include "http_core.h"
  #include "http_config.h"
  #include "unixd.h"
  #include "http_conf_globals.h"
  #include "dexter.h"
  #include "scoreboard.h"
  
  scoreboard ap_scoreboard_image[HARD_SERVER_LIMIT];
  
  void reinit_scoreboard(pool *p)
  {
      int i;
  
      for (i = 0; i < HARD_SERVER_LIMIT; i++) {
          ap_scoreboard_image[i].status = SERVER_DEAD;
          ap_scoreboard_image[i].pid = 0;
      }
  }
  
  API_EXPORT(int) find_child_by_pid(int pid)
  {
      int i;
  
      for (i = 0; i < max_daemons_limit; ++i)
  	if (ap_scoreboard_image[i].pid == pid)
  	    return i;
  
      return -1;
  }
  
  int ap_update_child_status(int child_num, int status)
  {
      int old_status;
  
      if (child_num < 0)
  	return -1;
  
      old_status = ap_scoreboard_image[child_num].status;
      ap_scoreboard_image[child_num].status = status;
  
      return old_status;
  }
  
  
  
  1.1                  apache-2.0/mpm/src/modules/mpm/dexter/scoreboard.h
  
  Index: scoreboard.h
  ===================================================================
  /* ====================================================================
   * Copyright (c) 1995-1999 The Apache Group.  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. All advertising materials mentioning features or use of this
   *    software must display the following acknowledgment:
   *    "This product includes software developed by the Apache Group
   *    for use in the Apache HTTP server project (http://www.apache.org/)."
   *
   * 4. The names "Apache Server" and "Apache Group" must not be used to
   *    endorse or promote products derived from this software without
   *    prior written permission. For written permission, please contact
   *    apache@apache.org.
   *
   * 5. Products derived from this software may not be called "Apache"
   *    nor may "Apache" appear in their names without prior written
   *    permission of the Apache Group.
   *
   * 6. Redistributions of any form whatsoever must retain the following
   *    acknowledgment:
   *    "This product includes software developed by the Apache Group
   *    for use in the Apache HTTP server project (http://www.apache.org/)."
   *
   * THIS SOFTWARE IS PROVIDED BY THE APACHE GROUP ``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 GROUP 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 Group and was originally based
   * on public domain software written at the National Center for
   * Supercomputing Applications, University of Illinois, Urbana-Champaign.
   * For more information on the Apache Group and the Apache HTTP server
   * project, please see <http://www.apache.org/>.
   *
   */
  
  #ifndef APACHE_SCOREBOARD_H
  #define APACHE_SCOREBOARD_H
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  #include "mpm_default.h"	/* For HARD_.*_LIMIT */
  
  /* Scoreboard info on a process is, for now, kept very brief --- 
   * just status value and pid (the latter so that the caretaker process
   * can properly update the scoreboard when a process dies).
   *
   * Status values:
   */
  
  #define SERVER_DEAD 0
  #define SERVER_ALIVE 1		/* Waiting for connection (or accept() lock) */
  #define SERVER_DYING 2		/* Waiting for connection (or accept() lock) */
  #define SERVER_NUM_STATUS 3	/* number of status settings */
  
  typedef struct {
      pid_t pid;
      unsigned char status;
  } scoreboard;
  
  void reinit_scoreboard(pool *p);
  
  API_EXPORT(int) find_child_by_pid(int pid);
  int ap_update_child_status(int child_num, int status);
  
  API_VAR_EXPORT extern scoreboard ap_scoreboard_image[HARD_SERVER_LIMIT];
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif	/* !APACHE_SCOREBOARD_H */