prefork.c revision 7b85491921b9bfae551088fad57aa683fb108311
/* ====================================================================
* 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
* 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/>.
*
*/
/*
* httpd.c: simple http daemon for answering WWW file requests
*
*
* 03-21-93 Rob McCool wrote original code (up to NCSA HTTPd 1.3)
*
* 03-06-95 blong
* changed server number for child-alone processes to 0 and changed name
* of processes
*
* 03-10-95 blong
* Added numerous speed hacks proposed by Robert S. Thau (rst@ai.mit.edu)
* including set group before fork, and call gettime before to fork
* to set up libraries.
*
* 04-14-95 rst / rh
* Brandon's code snarfed from NCSA 1.4, but tinkered to work with the
* Apache server, and also to have child processes do accept() directly.
*
* April-July '95 rst
* Extensive rework for Apache.
*/
/* TODO: this is a cobbled together prefork MPM example... it should mostly
* TODO: behave like apache-1.3... here's a short list of things I think
* TODO: need cleaning up still:
* TODO: - use ralf's mm stuff for the shared mem and mutexes
* TODO: - clean up scoreboard stuff when we figure out how to do it in 2.0
*/
#define CORE_PRIVATE
#include "apr_portable.h"
#include "httpd.h"
#include "mpm_default.h"
#include "http_main.h"
#include "http_log.h"
#include "http_config.h"
#include "http_core.h" /* for get_remote_host */
#include "http_connection.h"
#include "scoreboard.h"
#include "ap_mpm.h"
#include "unixd.h"
#include "iol_socket.h"
#include "ap_listen.h"
#ifdef USE_SHMGET_SCOREBOARD
#endif
#ifdef HAVE_BSTRING_H
#include <bstring.h> /* for IRIX, FD_SET calls bzero() */
#endif
/* config globals */
static int ap_max_requests_per_child=0;
static char *ap_pid_fname=NULL;
static char *ap_scoreboard_fname=NULL;
static char *ap_lock_fname;
static int ap_daemons_to_start=0;
static int ap_daemons_min_free=0;
static int ap_daemons_max_free=0;
static int ap_daemons_limit=0;
static time_t ap_restart_time=0;
static int ap_extended_status = 0;
/*
* The max child slot ever assigned, preserved across restarts. Necessary
* to deal with MaxClients changes across SIGUSR1 restarts. We use this
* value to optimize routines that have to scan the entire scoreboard.
*/
static int max_daemons_limit = -1;
static char ap_coredump_dir[MAX_STRING_LEN];
/* *Non*-shared http_main globals... */
static server_rec *server_conf;
static ap_socket_t *sd;
static int listenmaxfd;
/* 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 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 {
int pid;
void (*maintenance) (int, void *, ap_wait_t);
void *data;
int write_fd;
};
static other_child_rec *other_children;
#endif
static int my_pid; /* it seems silly to call getpid all the time */
#ifndef MULTITHREAD
static int my_child_num;
#endif
#ifdef TPF
int tpf_child = 0;
#endif /* TPF */
#ifdef GPROF
/*
* change directory for gprof to plop the gmon.out file
* configure in httpd.conf:
* GprofDir logs/ -> $ServerRoot/logs/gmon.out
* GprofDir logs/% -> $ServerRoot/logs/gprof.$pid/gmon.out
*/
static void chdir_for_gprof(void)
{
if(dir) {
char buf[512];
}
"gprof: error creating directory %s", dir);
}
}
else {
}
}
#else
#define chdir_for_gprof()
#endif
/* a clean exit from a child with proper cleanup */
static void clean_child_exit(int code)
{
if (pchild) {
}
}
#if defined(USE_FCNTL_SERIALIZED_ACCEPT) || defined(USE_FLOCK_SERIALIZED_ACCEPT)
static void expand_lock_fname(ap_context_t *p)
{
/* XXXX possibly bogus cast */
}
#endif
#if defined (USE_USLOCK_SERIALIZED_ACCEPT)
#include <ulocks.h>
#define accept_mutex_child_init(x)
static void accept_mutex_init(ap_context_t *p)
{
/* default is 8, allocate enough for all the children plus the parent */
perror("usconfig(CONF_INITUSERS)");
exit(-1);
}
perror("usconfig(CONF_LOCKTYPE)");
exit(-1);
}
perror("usconfig(CONF_ARENATYPE)");
exit(-1);
}
perror("usinit");
exit(-1);
}
perror("usnewlock");
exit(-1);
}
}
static void accept_mutex_on(void)
{
case 1:
/* got lock */
break;
case 0:
"didn't get lock");
case -1:
perror("ussetlock");
}
}
static void accept_mutex_off(void)
{
perror("usunsetlock");
}
}
#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 int have_accept_mutex;
static sigset_t accept_block_mask;
static sigset_t accept_previous_mask;
static void accept_mutex_child_cleanup(void *foo)
{
&& have_accept_mutex) {
}
}
static void accept_mutex_child_init(ap_context_t *p)
{
}
static void accept_mutex_cleanup(void *foo)
{
perror("munmap");
}
}
static void accept_mutex_init(ap_context_t *p)
{
int fd;
if (fd == -1) {
}
perror("mmap");
}
perror("pthread_mutexattr_init");
}
perror("pthread_mutexattr_setpshared");
}
perror("pthread_mutex_init");
}
}
static void accept_mutex_on(void)
{
int err;
perror("sigprocmask(SIG_BLOCK)");
}
perror("pthread_mutex_lock");
}
have_accept_mutex = 1;
}
static void accept_mutex_off(void)
{
int err;
perror("pthread_mutex_unlock");
}
/* 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 = 0;
perror("sigprocmask(SIG_SETMASK)");
clean_child_exit(1);
}
}
#elif defined (USE_SYSVSEM_SERIALIZED_ACCEPT)
#ifdef NEED_UNION_SEMUN
/* it makes no sense, but this isn't defined on solaris */
union semun {
long val;
};
#endif
static int sem_id = -1;
/* 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.
*/
static void accept_mutex_cleanup(void *foo)
{
if (sem_id < 0)
return;
/* this is ignored anyhow */
}
#define accept_mutex_child_init(x)
static void accept_mutex_init(ap_context_t *p)
{
/* acquire the semaphore */
if (sem_id < 0) {
perror("semget");
}
perror("semctl(SETVAL)");
}
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.
*/
perror("semctl(IPC_SET)");
}
}
/* preinitialize these */
}
static void accept_mutex_on(void)
{
perror("accept_mutex_on");
}
}
}
static void accept_mutex_off(void)
{
perror("accept_mutex_off");
}
}
}
#elif defined(USE_FCNTL_SERIALIZED_ACCEPT)
static int lock_fd = -1;
#define accept_mutex_child_init(x)
/*
* Initialize mutex lock.
* Must be safe to call this on a restart.
*/
static void accept_mutex_init(ap_context_t *p)
{
if (lock_fd == -1) {
perror("open");
"Cannot open lock file: %s", ap_lock_fname);
}
}
static void accept_mutex_on(void)
{
int ret;
/* nop */
}
if (ret < 0) {
"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!");
}
}
static void accept_mutex_off(void)
{
int ret;
/* nop */
}
if (ret < 0) {
"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!");
}
}
#elif defined(USE_FLOCK_SERIALIZED_ACCEPT)
static int lock_fd = -1;
{
return APR_SUCCESS;
}
/*
* Initialize mutex lock.
* Done by each child at it's birth
*/
static void accept_mutex_child_init(ap_context_t *p)
{
if (ret != APR_SUCCESS) {
"Child cannot open lock file: %s", ap_lock_fname);
}
}
/*
* Initialize mutex lock.
* Must be safe to call this on a restart.
*/
static void accept_mutex_init(ap_context_t *p)
{
APR_UREAD|APR_UWRITE, p);
if (ret != APR_SUCCESS) {
"Parent cannot open lock file: %s", ap_lock_fname);
}
}
static void accept_mutex_on(void)
{
int ret;
continue;
if (ret < 0) {
"flock: LOCK_EX: Error getting accept lock. Exiting!");
}
}
static void accept_mutex_off(void)
{
"flock: LOCK_UN: Error freeing accept lock. Exiting!");
}
}
#elif defined(USE_OS2SEM_SERIALIZED_ACCEPT)
static void accept_mutex_cleanup(void *foo)
{
}
/*
* Initialize mutex lock.
* Done by each child at it's birth
*/
static void accept_mutex_child_init(ap_context_t *p)
{
if (rc != 0) {
"Child cannot open lock semaphore, rc=%d", rc);
} else {
}
}
/*
* Initialize mutex lock.
* Must be safe to call this on a restart.
*/
static void accept_mutex_init(ap_context_t *p)
{
if (rc != 0) {
"Parent cannot create lock semaphore, rc=%d", rc);
}
}
static void accept_mutex_on(void)
{
if (rc != 0) {
"OS2SEM: Error %d getting accept lock. Exiting!", rc);
}
}
static void accept_mutex_off(void)
{
if (rc != 0) {
"OS2SEM: Error %d freeing accept lock. Exiting!", rc);
}
}
#elif defined(USE_TPF_CORE_SERIALIZED_ACCEPT)
static int tpf_core_held;
static void accept_mutex_cleanup(void *foo)
{
if(tpf_core_held)
}
#define accept_mutex_init(x)
static void accept_mutex_child_init(ap_context_t *p)
{
tpf_core_held = 0;
}
static void accept_mutex_on(void)
{
tpf_core_held = 1;
}
static void accept_mutex_off(void)
{
tpf_core_held = 0;
}
#else
/* Default --- no serialization. Other methods *could* go here,
* as #elifs...
*/
#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)
#define accept_mutex_on()
#define accept_mutex_off()
#endif
#endif
/* On some architectures it's safe to do unserialized accept()s in the single
* Listen case. But it's never safe to do it in the case where there's
* multiple Listen statements. Define SINGLE_LISTEN_UNSERIALIZED_ACCEPT
* when it's safe in the single Listen case.
*/
#else
#endif
/*****************************************************************
* dealing with other children
*/
#ifdef HAS_OTHER_CHILD
{
}
/* 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.
*/
{
/* 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)
{
int fd_max;
int rc;
if (other_children == NULL)
return;
fd_max = 0;
do {
continue;
}
}
if (fd_max == 0)
return;
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 */
"could not probe writable fds", server_conf);
return;
}
if (rc == 0)
return;
continue;
continue;
}
}
/* possibly reap an other_child, return 0 if yes, -1 if not */
{
continue;
return 0;
}
return -1;
}
#endif
/*****************************************************************
*
* Dealing with the scoreboard... a lot of these variables are global
* only to avoid getting clobbered by the longjmp() that happens when
* a hard timeout expires...
*
* We begin with routines which deal with the file itself...
*/
#if defined(USE_OS2_SCOREBOARD)
/* The next two routines are used to access shared memory under OS/2. */
/* This requires EMX v09c to be installed. */
{
void *mem;
Heap_t h;
if (rc != 0)
return NULL;
if (h == NULL)
return (caddr_t) h;
}
{
the shared memory object */
of the shared memory object */
/* Request read and write access to */
/* the shared memory object */
if (rc != 0) {
return 0;
}
return BaseAddress;
}
static void setup_shared_mem(ap_context_t *p)
{
caddr_t m;
int rc;
if (m == 0) {
"%s: Could not create OS/2 Shared memory pool.",
}
if (rc != 0) {
"%s: Could not uopen() newly created OS/2 Shared memory pool.",
}
ap_scoreboard_image = (scoreboard *) m;
}
static void reopen_scoreboard(ap_context_t *p)
{
caddr_t m;
int rc;
if (m == 0) {
"%s: Could not find existing OS/2 Shared memory pool.",
}
ap_scoreboard_image = (scoreboard *) m;
}
#elif defined(USE_POSIX_SCOREBOARD)
/*
* POSIX 1003.4 style
*
* Note 1:
* where no subdirectories allowed.
*
* POSIX shm_open() and shm_unlink() will take care about this issue,
* but to avoid confusion, I suggest to redefine scoreboard file name
* in httpd.conf to cut "logs/" from it. With default setup actual name
* will be "/dev/shmem/logs.apache_status".
*
* If something went wrong and Apache did not unlinked this object upon
* exit, you can remove it manually, using "rm -f" command.
*
* Note 2:
* does NOT support BSD style anonymous mapping. So, the order of
* conditional compilation is important:
* this #ifdef section must be ABOVE the next one (BSD style).
*
* I tested this stuff and it works fine for me, but if it provides
* trouble for you, just comment out USE_MMAP_SCOREBOARD in QNX section
* of ap_config.h
*
* June 5, 1997,
* Igor N. Kovalenko -- infoh@mail.wplus.net
*/
static void cleanup_shared_mem(void *d)
{
}
static void setup_shared_mem(ap_context_t *p)
{
char buf[512];
caddr_t m;
int fd;
if (fd == -1) {
}
}
}
ap_scoreboard_image = (scoreboard *) m;
}
static void reopen_scoreboard(ap_context_t *p)
{
}
#elif defined(USE_MMAP_SCOREBOARD)
static void setup_shared_mem(ap_context_t *p)
{
caddr_t m;
#if defined(MAP_ANON)
/* BSD style */
#ifdef CONVEXOS11
/*
* 9-Aug-97 - Jeff Venters (venters@convex.hp.com)
* ConvexOS maps address space as follows:
* 0x00000000 - 0x7fffffff : Kernel
* 0x80000000 - 0xffffffff : User
* Start mmapped area 1GB above start of text.
*
* Also, the length requires a pointer as the actual length is
* returned (rounded up to a page boundary).
*/
{
unsigned len = SCOREBOARD_SIZE;
}
#elif defined(MAP_TMPFILE)
{
char mfile[] = "/tmp/apache_shmem_XXXX";
if (fd == -1) {
perror("open");
}
if (m == (caddr_t) - 1) {
perror("mmap");
}
}
#else
#endif
if (m == (caddr_t) - 1) {
perror("mmap");
"%s: Could not mmap memory", ap_server_argv0);
}
#else
/* Sun style */
int fd;
if (fd == -1) {
perror("open");
"%s: Could not open /dev/zero", ap_server_argv0);
}
if (m == (caddr_t) - 1) {
perror("mmap");
"%s: Could not mmap /dev/zero", ap_server_argv0);
}
#endif
ap_scoreboard_image = (scoreboard *) m;
}
static void reopen_scoreboard(ap_context_t *p)
{
}
#elif defined(USE_SHMGET_SCOREBOARD)
static int shmid = -1;
static void setup_shared_mem(ap_context_t *p)
{
#ifdef MOVEBREAK
char *obrk;
#endif
#ifdef LINUX
"Your kernel was built without CONFIG_SYSVIPC\n"
"%s: Please consult the Apache FAQ for details",
}
#endif
"could not call shmget");
}
"created shared memory segment #%d", shmid);
#ifdef MOVEBREAK
/*
* Some SysV systems place the shared segment WAY too close
* to the dynamic memory break point (sbrk(0)). This severely
* refuse to move past that point.
*
* To get around this, we move the break point "way up there",
* attach the segment and then move break back down. Ugly
*/
"sbrk() could not move break");
}
#endif
/*
* We exit below, after we try to remove the segment
*/
}
else { /* only worry about permissions if we attached the segment */
"shmctl() could not stat segment #%d", shmid);
}
else {
"shmctl() could not set segment #%d", shmid);
}
}
}
/*
* We must avoid leaving segments in the kernel's
* (small) tables.
*/
"shmctl: IPC_RMID: could not remove shared memory segment #%d",
shmid);
}
#ifdef MOVEBREAK
if (obrk == (char *) -1)
return; /* nothing else to do */
"sbrk() could not move break back");
}
#endif
}
static void reopen_scoreboard(ap_context_t *p)
{
}
#elif defined(USE_TPF_SCOREBOARD)
static void cleanup_scoreboard_heap()
{
int rv;
if(rv == RSYSC_ERROR) {
"rsysc() could not release scoreboard system heap");
}
}
static void setup_shared_mem(ap_context_t *p)
{
if (!ap_scoreboard_image) {
"httpd: Could not create scoreboard system heap storage.");
}
}
static void reopen_scoreboard(ap_context_t *p)
{
}
#else
#define SCOREBOARD_FILE
static scoreboard _scoreboard_image;
static int scoreboard_fd = -1;
/* XXX: things are seriously screwed if we ever have to do a partial
* read or write ... we could get a corrupted scoreboard
*/
{
do {
if (rv > 0) {
}
}
{
do {
if (rv > 0) {
}
}
static void cleanup_scoreboard_file(void *foo)
{
}
void reopen_scoreboard(ap_context_t *p)
{
if (scoreboard_fd != -1)
ap_pclosef(p, scoreboard_fd);
#ifdef TPF
#endif /* TPF */
if (scoreboard_fd == -1) {
"Cannot open scoreboard file:");
clean_child_exit(1);
}
}
#endif
/* Called by parent process */
static void reinit_scoreboard(ap_context_t *p)
{
int running_gen = 0;
if (ap_scoreboard_image)
#ifndef SCOREBOARD_FILE
if (ap_scoreboard_image == NULL) {
setup_shared_mem(p);
}
#else
if (scoreboard_fd == -1) {
"Cannot open scoreboard file:");
}
#endif
}
/* Routines called to deal with the scoreboard image
* --- note that we do *not* need write locks, since update_child_status
* only updates a *single* record in place, and only one process writes to
* a given scoreboard slot at a time (either the child process owning that
* slot, or the parent, noting that the child has died).
*
* As a final note --- setting the score entry to getpid() is always safe,
* since when the parent is writing an entry, it's only noting SERVER_DEAD
* anyway.
*/
ap_inline void ap_sync_scoreboard_image(void)
{
#ifdef SCOREBOARD_FILE
lseek(scoreboard_fd, 0L, 0);
#endif
}
API_EXPORT(int) ap_exists_scoreboard_image(void)
{
return (ap_scoreboard_image ? 1 : 0);
}
{
#ifdef SCOREBOARD_FILE
#endif
}
{
int old_status;
if (child_num < 0)
return -1;
if (ap_extended_status) {
/*
* Reset individual counters
*/
if (status == SERVER_DEAD) {
ss->my_access_count = 0L;
ss->my_bytes_served = 0L;
}
ss->conn_count = (unsigned short) 0;
ss->conn_bytes = (unsigned long) 0;
}
if (r) {
conn_rec *c = r->connection;
if (r->the_request == NULL) {
} else {
/* Don't reveal the password in the server-status view */
}
}
}
/* clean up the slot's vhostrec pointer (maybe re-used)
* and mark the slot as belonging to a new generation.
*/
#ifdef SCOREBOARD_FILE
sizeof(parent_score));
#endif
}
return old_status;
}
static void update_scoreboard_global(void)
{
#ifdef SCOREBOARD_FILE
sizeof ap_scoreboard_image->global);
#endif
}
{
#if !defined(HAVE_GETTIMEOFDAY) && !defined(NO_TIMES)
#endif
if (child_num < 0)
return;
if (status == START_PREQUEST) {
#if !defined(HAVE_GETTIMEOFDAY)
#ifndef NO_TIMES
#endif /* NO_TIMES */
#else
#endif
}
else if (status == STOP_PREQUEST) {
#if !defined(HAVE_GETTIMEOFDAY)
#ifndef NO_TIMES
#endif
#else
#endif
}
}
/*
static void increment_counts(int child_num, request_rec *r)
{
long int bs = 0;
short_score *ss;
ap_sync_scoreboard_image();
ss = &ap_scoreboard_image->servers[child_num];
if (r->sent_bodyct)
ap_bgetopt(r->connection->client, BO_BYTECT, &bs);
#ifndef NO_TIMES
times(&ss->times);
#endif
ss->access_count++;
ss->my_access_count++;
ss->conn_count++;
ss->bytes_served += (unsigned long) bs;
ss->my_bytes_served += (unsigned long) bs;
ss->conn_bytes += (unsigned long) bs;
put_scoreboard_info(child_num, ss);
}
*/
static int find_child_by_pid(int pid)
{
int i;
for (i = 0; i < max_daemons_limit; ++i)
return i;
return -1;
}
static void reclaim_child_processes(int terminate)
{
#ifndef MULTITHREAD
int i, status;
int not_dead_yet;
#ifdef HAS_OTHER_CHILD
#endif
/* 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.
*/
/* now see who is done */
not_dead_yet = 0;
for (i = 0; i < max_daemons_limit; ++i) {
continue;
continue;
}
++not_dead_yet;
switch (tries) {
case 1: /* 16ms */
case 2: /* 82ms */
break;
case 3: /* 344ms */
/* perhaps it missed the SIGHUP, lets try again */
0, server_conf,
"child process %d did not exit, sending another SIGHUP",
pid);
break;
case 4: /* 16ms */
case 5: /* 82ms */
case 6: /* 344ms */
break;
case 7: /* 1.4sec */
/* ok, now it's being annoying */
0, server_conf,
"child process %d still did not exit, sending a SIGTERM",
pid);
break;
case 8: /* 6 sec */
/* die child scum */
"child process %d still did not exit, sending a SIGKILL",
pid);
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.
*/
"could not make child process %d exit, "
"attempting to continue anyway", pid);
break;
}
}
#ifdef HAS_OTHER_CHILD
continue;
}
else if (waitret == 0) {
++not_dead_yet;
}
else if (waitret == -1) {
/* uh what the heck? they didn't call unregister? */
}
}
#endif
if (!not_dead_yet) {
/* nothing left to wait for */
break;
}
}
#endif /* ndef MULTITHREAD */
}
#if defined(NEED_WAITPID)
/*
Systems without a real waitpid sometimes lose a child's exit while waiting
for another. Search through the scoreboard for missing children.
*/
{
int n, pid;
for (n = 0; n < max_daemons_limit; ++n) {
/* just mark it as having a successful exit status */
return(pid);
}
}
return 0;
}
#endif
/* 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;
{
int ret;
#ifdef HAS_OTHER_CHILD
#endif
}
return -1;
}
if (ret > 0) {
return ret;
}
#ifdef NEED_WAITPID
return ret;
}
#endif
return -1;
}
/* handle all varieties of core dumping signals */
static void sig_coredump(int 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.
*/
}
/*****************************************************************
* Connection structures and accounting...
*/
{
clean_child_exit(0);
}
static int volatile deferred_die;
static int volatile usr1_just_die;
static void usr1_handler(int sig)
{
if (usr1_just_die) {
}
deferred_die = 1;
}
/* volatile just in case */
static int volatile shutdown_pending;
static int volatile restart_pending;
static int volatile is_graceful;
ap_generation_t volatile ap_my_generation=0;
{
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;
}
{
if (restart_pending == 1) {
/* Probably not an error - don't bother reporting it */
return;
}
restart_pending = 1;
}
static void set_signals(void)
{
#ifndef NO_USE_SIGACTION
if (!one_process) {
#if defined(SA_ONESHOT)
#elif defined(SA_RESETHAND)
#endif
#ifdef SIGBUS
#endif
#ifdef SIGABORT
#endif
#ifdef SIGABRT
#endif
#ifdef SIGILL
#endif
}
#ifdef SIGINT
#endif
#ifdef SIGXCPU
#endif
#ifdef SIGXFSZ
#endif
#ifdef SIGPIPE
#endif
/* we want to ignore HUPs and USR1 while we're busy processing one */
#else
if (!one_process) {
#ifdef SIGBUS
#endif /* SIGBUS */
#ifdef SIGABORT
#endif /* SIGABORT */
#ifdef SIGABRT
#endif /* SIGABRT */
#ifdef SIGILL
#endif /* SIGILL */
#ifdef SIGXCPU
#endif /* SIGXCPU */
#ifdef SIGXFSZ
#endif /* SIGXFSZ */
}
#ifdef SIGHUP
#endif /* SIGHUP */
#ifdef SIGUSR1
#endif /* SIGUSR1 */
#ifdef SIGPIPE
#endif /* SIGPIPE */
#endif
}
static void sock_disable_nagle(int s)
{
/* 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;
sizeof(int)) < 0) {
"setsockopt: (TCP_NODELAY)");
}
}
#else
#define sock_disable_nagle(s) /* NOOP */
#endif
/*****************************************************************
* Child process main loop.
* The following vars are static to avoid getting clobbered by longjmp();
* they are really private to child_main.
*/
static int srv;
static ap_socket_t *csd;
static int requests_this_child;
{
r->connection->keepalive = 0;
}
int ap_graceful_stop_signalled(void)
{
if (deferred_die ||
return 1;
}
return 0;
}
static void child_main(int child_num_arg)
{
int sockdes;
requests_this_child = 0;
/* Get a sub context for global allocations in this child, so that
* we can have cleanups occur when the child exits.
*/
/* needs to be done before we switch UIDs so we have permissions */
if (unixd_setup_child()) {
}
#ifdef OS2
/* Stop Ctrl-C/Ctrl-Break signals going to child processes */
{
unsigned long ulTimes;
}
#endif
while (!ap_graceful_stop_signalled()) {
/* Prepare to receive a SIGUSR1 due to graceful restart so that
* we can exit cleanly.
*/
usr1_just_die = 1;
/*
* (Re)initialize this child to a pre-connection state.
*/
current_conn = NULL;
if ((ap_max_requests_per_child > 0
&& requests_this_child++ >= ap_max_requests_per_child)) {
clean_child_exit(0);
}
/*
* Wait for an acceptable connection to arrive.
*/
/* Lock around "accept", if necessary */
for (;;) {
if (ap_listeners->next) {
/* more than one socket */
/* Single Unix documents select as returning errnos
* EBADF, EINTR, and EINVAL... and in none of those
* cases does it make sense to continue. In fact
* on Linux 2.0.x we seem to end up with EFAULT
* occasionally, and we'd loop forever due to it.
*/
clean_child_exit(1);
}
if (srv <= 0)
continue;
/* we remember the last_lr we searched last time around so that
we don't end up starving any particular listening socket */
lr = ap_listeners;
}
else {
if (!lr)
lr = ap_listeners;
}
do {
goto got_listener;
if (!lr)
lr = ap_listeners;
}
/* FIXME: if we get here, something bad has happened, and we're
probably gonna spin forever.
*/
continue;
}
else {
/* only one socket, just pretend we did the other stuff */
}
/* if we accept() something we don't want to die, so we have to
* defer the exit
*/
usr1_just_die = 0;
for (;;) {
if (deferred_die) {
/* we didn't get a socket, and we were told to die */
clean_child_exit(0);
}
break;
}
if (stat == APR_SUCCESS)
break; /* We have a socket ready for reading */
else {
/* TODO: this accept result handling stuff should be abstracted...
* it's already out of date between the various unix mpms
*/
/* Our old behaviour here was to continue after accept()
* errors. But this leads us into lots of troubles
* because most of the errors are quite fatal. For
* example, EMFILE can be caused by slow descriptor
* leaks (say in a 3rd party module, or libc). It's
* foolish for us to continue after an EMFILE. We also
* seem to tickle kernel bugs on some platforms which
* lead to never-ending loops here. So it seems best
* to just exit in most cases.
*/
switch (errno) {
#ifdef EPROTO
/* EPROTO on certain older kernels really means
* ECONNABORTED, so we need to ignore it for them.
* See discussion in new-httpd archives nh.9701
* search for EPROTO.
*
* Also see nh.9603, search for EPROTO:
* There is potentially a bug in Solaris 2.x x<6,
* and other boxes that implement tcp sockets in
* userland (i.e. on top of STREAMS). On these
* systems, EPROTO can actually result in a fatal
* loop. See PR#981 for example. It's hard to
* handle both uses of EPROTO.
*/
case EPROTO:
#endif
#ifdef ECONNABORTED
case ECONNABORTED:
#endif
/* Linux generates the rest of these, other tcp
* stacks (i.e. bsd) tend to hide them behind
* getsockopt() interfaces. They occur when
* the net goes sour or the client disconnects
* after the three-way handshake has been done
* in the kernel but before userland has picked
* up the socket.
*/
#ifdef ECONNRESET
case ECONNRESET:
#endif
#ifdef ETIMEDOUT
case ETIMEDOUT:
#endif
#ifdef EHOSTUNREACH
case EHOSTUNREACH:
#endif
#ifdef ENETUNREACH
case ENETUNREACH:
#endif
break;
#ifdef ENETDOWN
case ENETDOWN:
/*
* When the network layer has been shut down, there
* is not much use in simply exiting: the parent
* would simply re-create us (and we'd fail again).
* Use the CHILDFATAL code to tear the server down.
* @@@ Martin's idea for possible improvement:
* A different approach would be to define
* a new APEXIT_NETDOWN exit code, the reception
* of which would make the parent shutdown all
* children, then idle-loop until it detected that
* the network is up again, and restart the children.
* Ben Hyde noted that temporary ENETDOWN situations
* occur in mobile IP.
*/
"accept: giving up.");
#endif /*ENETDOWN*/
#ifdef TPF
case EINACT:
"offload device inactive");
break;
default:
#else
default:
"accept: (client socket)");
clean_child_exit(1);
#endif
}
}
if (ap_graceful_stop_signalled()) {
clean_child_exit(0);
}
usr1_just_die = 1;
}
#ifdef TPF
if (csd == 0) /* 0 is invalid socket for TPF */
continue;
#endif
/* We've got a socket, let's at least process one request off the
* socket before we accept a graceful restart request. We set
* the signal to ignore because we don't want to disturb any
* third party code.
*/
/*
* We now have a connection, so set it up with the appropriate
*/
continue;
}
"filedescriptor (%u) larger than FD_SETSIZE (%u) "
"found, you probably need to rebuild Apache with a "
}
else {
"error attaching to socket");
}
continue;
}
(request_rec *) NULL);
}
}
{
int pid;
}
if (one_process) {
#ifdef SIGQUIT
#endif
}
#ifdef _OSD_POSIX
/* BS2000 requires a "special" version of fork() before a setuid() call */
#else
#endif
/* fork didn't succeed. Fix the scoreboard or else
* it will say SERVER_STARTING forever and ever
*/
/* 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>
"processor unbind failed %d", status);
}
#endif
/* Disable the restart signal handlers and enable the just_die stuff.
* Note that since restart() just notes that a restart has been
* requested there's no race condition here.
*/
}
#ifdef SCOREBOARD_FILE
sizeof(parent_score));
#endif
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_daemons_limit; ++i) {
continue;
}
break;
}
}
}
/*
* idle_spawn_rate is the number of children that will be spawned on the
* next maintenance cycle if there aren't enough idle servers. It is
* doubled up to MAX_SPAWN_RATE, and reset only when a cycle goes by
* without the need to spawn.
*/
static int idle_spawn_rate = 1;
#ifndef MAX_SPAWN_RATE
#define MAX_SPAWN_RATE (32)
#endif
static int hold_off_on_exponential_spawning;
static void perform_idle_server_maintenance(void)
{
int i;
int to_kill;
int idle_count;
int free_length;
int free_slots[MAX_SPAWN_RATE];
int last_non_dead;
int total_non_dead;
/* initialize the free_list */
free_length = 0;
to_kill = -1;
idle_count = 0;
last_non_dead = -1;
total_non_dead = 0;
for (i = 0; i < ap_daemons_limit; ++i) {
int status;
break;
if (status == SERVER_DEAD) {
/* try to keep children numbers as low as possible */
if (free_length < idle_spawn_rate) {
free_slots[free_length] = i;
++free_length;
}
}
else {
/* We consider a starting server as idle because we started it
* at least a cycle ago, and if it still hasn't finished starting
* then we're just going to swamp things worse by forking more.
* So we hopefully won't need to fork more if we count it.
* This depends on the ordering of SERVER_READY and SERVER_STARTING.
*/
if (status <= SERVER_READY) {
++ idle_count;
/* always kill the highest numbered child if we have to...
* no really well thought out reason ... other than observing
* the server behaviour under linux where lower numbered children
* tend to service more hits (and hence are more likely to have
* their data in cpu caches).
*/
to_kill = i;
}
last_non_dead = i;
}
}
if (idle_count > ap_daemons_max_free) {
/* kill off one child... we use SIGUSR1 because that'll cause it to
* shut down gracefully, in case it happened to pick up a request
* while we were counting
*/
idle_spawn_rate = 1;
}
else if (idle_count < ap_daemons_min_free) {
/* terminate the free list */
if (free_length == 0) {
/* only report this condition once */
static int reported = 0;
if (!reported) {
"server reached MaxClients setting, consider"
" raising the MaxClients setting");
reported = 1;
}
idle_spawn_rate = 1;
}
else {
if (idle_spawn_rate >= 8) {
"server seems busy, (you may need "
"to increase StartServers, or Min/MaxSpareServers), "
"spawning %d children, there are %d idle, and "
"%d total children", idle_spawn_rate,
}
for (i = 0; i < free_length; ++i) {
#ifdef TPF
if(free_length == 1) {
shutdown_pending = 1;
"No active child processes: shutting down");
}
}
#else
#endif /* TPF */
}
/* 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
*/
}
else if (idle_spawn_rate < MAX_SPAWN_RATE) {
idle_spawn_rate *= 2;
}
}
}
else {
idle_spawn_rate = 1;
}
}
{
/* Child died... if it died due to a fatal error,
* we should simply bail out.
*/
"Child %d returned a Fatal error... \n"
"Apache is exiting!",
pid);
}
if (WIFSIGNALED(status)) {
case SIGTERM:
case SIGHUP:
case SIGUSR1:
case SIGKILL:
break;
default:
#ifdef SYS_SIGLIST
#ifdef WCOREDUMP
0, server_conf,
"child pid %d exit signal %s (%d), "
"possible coredump in %s",
}
else {
#endif
0, server_conf,
"child pid %d exit signal %s (%d)", pid,
#ifdef WCOREDUMP
}
#endif
#else
"child pid %d exit signal %d",
#endif
}
}
}
static int setup_listeners(server_rec *s)
{
int sockdes;
"no listening sockets available, shutting down");
return -1;
}
listenmaxfd = -1;
if (sockdes > listenmaxfd) {
}
}
return 0;
}
/*****************************************************************
* Executive routines.
*/
{
server_conf = s;
if (setup_listeners(s)) {
/* XXX: hey, what's the right way for the mpm to indicate a fatal error? */
return 1;
}
if (!is_graceful) {
}
#ifdef SCOREBOARD_FILE
else {
}
#endif
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 SIGUSR1). 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.
*/
}
if (!is_graceful) {
}
else {
/* give the system some time to recover before kicking into
* exponential mode */
}
"%s configured -- resuming normal operations",
"Server built: %s", ap_get_server_built());
restart_pending = shutdown_pending = 0;
while (!restart_pending && !shutdown_pending) {
int child_slot;
/* XXX: if it takes longer than 1 second for all our children
* to start up and get into IDLE state then we may spawn an
* extra child
*/
if (pid >= 0) {
/* non-fatal death... note that it's gone in the scoreboard. */
if (child_slot >= 0) {
(request_rec *) NULL);
&& child_slot < ap_daemons_limit) {
/* we're still doing a 1-for-1 replacement of dead
* children with new children
*/
}
#ifdef HAS_OTHER_CHILD
}
/* 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.
*/
0, 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.
*/
/* 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;
}
#ifdef TPF
sleep(1);
#endif /*TPF */
}
if (shutdown_pending) {
/* Time to gracefully shut down:
* Kill child processes, tell them to call child_exit, etc...
*/
}
/* cleanup pid file on normal shutdown */
{
0, server_conf,
"removed PID file %s (pid=%ld)",
}
"caught SIGTERM, shutting down");
return 1;
}
/* we've been told to restart */
if (one_process) {
/* not worth thinking about */
return 1;
}
/* advance to the next generation */
/* XXX: we really need to make sure this new generation number isn't in
* use by any of the children.
*/
if (is_graceful) {
#ifndef SCOREBOARD_FILE
int i;
#endif
"SIGUSR1 received. Doing graceful restart");
/* kill off the idle ones */
}
#ifndef SCOREBOARD_FILE
/* This is mostly for debugging... so that we know what is still
* gracefully dealing with existing request. But we can't really
* do it if we're in a SCOREBOARD_FILE because it'll cause
* corruption too easily.
*/
for (i = 0; i < ap_daemons_limit; ++i) {
}
}
#endif
}
else {
/* Kill 'em off */
}
reclaim_child_processes(0); /* Not when just starting up */
"SIGHUP received. Attempting to restart");
}
if (!is_graceful) {
}
return 0;
}
{
static int restart_num = 0;
/* sigh, want this only the second time around */
if (restart_num++ == 1) {
is_graceful = 0;
if (!one_process) {
unixd_detach();
}
}
ap_extended_status = 0;
}
static void prefork_hooks(void)
{
INIT_SIGLIST();
#ifdef AUX3
(void) set42sig();
#endif
/* TODO: set one_process properly */ one_process = 0;
}
{
return err;
}
return "PidFile directive not allowed in <VirtualHost>";
}
ap_pid_fname = arg;
return NULL;
}
{
return err;
}
return NULL;
}
{
return err;
}
ap_lock_fname = arg;
return NULL;
}
{
return err;
}
return NULL;
}
{
return err;
}
if (ap_daemons_min_free <= 0) {
"WARNING: detected MinSpareServers set to non-positive.");
"Resetting to 1 to avoid almost certain Apache failure.");
"Please read the documentation.");
ap_daemons_min_free = 1;
}
return NULL;
}
{
return err;
}
return NULL;
}
{
return err;
}
if (ap_daemons_limit > HARD_SERVER_LIMIT) {
"WARNING: MaxClients of %d exceeds compile time limit "
" lowering MaxClients to %d. To increase, please "
"see the", HARD_SERVER_LIMIT);
}
else if (ap_daemons_limit < 1) {
"WARNING: Require MaxClients > 0, setting to 1");
ap_daemons_limit = 1;
}
return NULL;
}
{
return err;
}
return NULL;
}
{
const char *fname;
return err;
}
" does not exist or is not a directory", NULL);
}
return NULL;
}
/* Stub functions until this MPM supports the connection status API */
const char *value)
{
/* NOP */
}
{
/* NOP */
}
static const command_rec prefork_cmds[] = {
"A file for logging the server process ID"},
"A file for Apache to maintain runtime process management information"},
"The lockfile used when Apache needs to lock the accept() call"},
"Number of child processes launched at server startup" },
"Minimum number of idle children, to handle request spikes" },
"Maximum number of idle children" },
"Maximum number of children alive at the same time" },
"Maximum number of requests a particular child serves before dying." },
"The location of the directory Apache changes to before dumping core" },
{ NULL }
};
NULL, /* create per-directory config structure */
NULL, /* merge per-directory config structures */
NULL, /* create per-server config structure */
NULL, /* merge per-server config structures */
prefork_cmds, /* command ap_table_t */
NULL, /* handlers */
prefork_hooks, /* register hooks */
};