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diff --git a/rubbos/app/httpd-2.0.64/server/mpm/experimental/leader/leader.c b/rubbos/app/httpd-2.0.64/server/mpm/experimental/leader/leader.c
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+++ b/rubbos/app/httpd-2.0.64/server/mpm/experimental/leader/leader.c
@@ -0,0 +1,1976 @@
+/* Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "apr.h"
+#include "apr_portable.h"
+#include "apr_strings.h"
+#include "apr_file_io.h"
+#include "apr_thread_proc.h"
+#include "apr_signal.h"
+#include "apr_thread_cond.h"
+#include "apr_thread_mutex.h"
+#include "apr_proc_mutex.h"
+#define APR_WANT_STRFUNC
+#include "apr_want.h"
+
+#if APR_HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#if APR_HAVE_SYS_SOCKET_H
+#include <sys/socket.h>
+#endif
+#if APR_HAVE_SYS_WAIT_H
+#include <sys/wait.h>
+#endif
+#ifdef HAVE_SYS_PROCESSOR_H
+#include <sys/processor.h> /* for bindprocessor() */
+#endif
+
+#if !APR_HAS_THREADS
+#error The Leader/Follower MPM requires APR threads, but they are unavailable.
+#endif
+
+#define CORE_PRIVATE
+
+#include "ap_config.h"
+#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 "mpm_common.h"
+#include "ap_listen.h"
+#include "scoreboard.h"
+#include "mpm_default.h"
+#include "apr_poll.h"
+
+#include <signal.h>
+#include <limits.h> /* for INT_MAX */
+
+#include "apr_atomic.h"
+
+/* 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 DEFAULT_SERVER_LIMIT
+#define DEFAULT_SERVER_LIMIT 16
+#endif
+
+/* Admin can't tune ServerLimit beyond MAX_SERVER_LIMIT. We want
+ * some sort of compile-time limit to help catch typos.
+ */
+#ifndef MAX_SERVER_LIMIT
+#define MAX_SERVER_LIMIT 20000
+#endif
+
+/* Limit on the threads per process. Clients will be locked out if more than
+ * this * 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 DEFAULT_THREAD_LIMIT
+#define DEFAULT_THREAD_LIMIT 64
+#endif
+
+/* Admin can't tune ThreadLimit beyond MAX_THREAD_LIMIT. We want
+ * some sort of compile-time limit to help catch typos.
+ */
+#ifndef MAX_THREAD_LIMIT
+#define MAX_THREAD_LIMIT 20000
+#endif
+
+/*
+ * Actual definitions of config globals
+ */
+
+int ap_threads_per_child = 0; /* Worker threads per child */
+static int ap_daemons_to_start = 0;
+static int min_spare_threads = 0;
+static int max_spare_threads = 0;
+static int ap_daemons_limit = 0;
+static int server_limit = DEFAULT_SERVER_LIMIT;
+static int first_server_limit;
+static int thread_limit = DEFAULT_THREAD_LIMIT;
+static int first_thread_limit;
+static int changed_limit_at_restart;
+static int dying = 0;
+static int workers_may_exit = 0;
+static int start_thread_may_exit = 0;
+static int requests_this_child;
+static int num_listensocks = 0;
+static int resource_shortage = 0;
+static int mpm_state = AP_MPMQ_STARTING;
+
+typedef struct worker_wakeup_info worker_wakeup_info;
+
+/* The structure used to pass unique initialization info to each thread */
+typedef struct {
+ int pid;
+ int tid;
+ int sd;
+} proc_info;
+
+
+/* Structure used to pass information to the thread responsible for
+ * creating the rest of the threads.
+ */
+typedef struct {
+ apr_thread_t **threads;
+ int child_num_arg;
+ apr_threadattr_t *threadattr;
+} thread_starter;
+
+#define ID_FROM_CHILD_THREAD(c, t) ((c * thread_limit) + t)
+
+/*
+ * The max child slot ever assigned, preserved across restarts. Necessary
+ * to deal with MaxClients changes across AP_SIG_GRACEFUL restarts. We
+ * use this value to optimize routines that have to scan the entire
+ * scoreboard.
+ */
+int ap_max_daemons_limit = -1;
+
+static ap_pod_t *pod;
+
+/* *Non*-shared http_main globals... */
+
+server_rec *ap_server_conf;
+
+/* This MPM respects a couple of runtime flags that can aid in debugging.
+ * Setting the -DNO_DETACH flag will prevent the root process from
+ * detaching from its controlling terminal. Additionally, setting
+ * the -DONE_PROCESS flag (which implies -DNO_DETACH) will get you the
+ * child_main loop running in the process which originally started up.
+ * This gives you 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
+
+static apr_pool_t *pconf; /* Pool for config stuff */
+static apr_pool_t *pchild; /* Pool for httpd child stuff */
+
+static pid_t ap_my_pid; /* Linux getpid() doesn't work except in main
+ thread. Use this instead */
+static pid_t parent_pid;
+
+/* Locks for accept serialization */
+static apr_proc_mutex_t *accept_mutex;
+
+#ifdef SINGLE_LISTEN_UNSERIALIZED_ACCEPT
+#define SAFE_ACCEPT(stmt) (ap_listeners->next ? (stmt) : APR_SUCCESS)
+#else
+#define SAFE_ACCEPT(stmt) (stmt)
+#endif
+
+
+/* Structure used to wake up an idle worker thread
+ */
+struct worker_wakeup_info {
+ apr_uint32_t next; /* index into worker_wakeups array,
+ * used to build a linked list
+ */
+ apr_thread_cond_t *cond;
+ apr_thread_mutex_t *mutex;
+};
+
+static worker_wakeup_info *worker_wakeup_create(apr_pool_t *pool)
+{
+ apr_status_t rv;
+ worker_wakeup_info *wakeup;
+
+ wakeup = (worker_wakeup_info *)apr_palloc(pool, sizeof(*wakeup));
+ if ((rv = apr_thread_cond_create(&wakeup->cond, pool)) != APR_SUCCESS) {
+ return NULL;
+ }
+ if ((rv = apr_thread_mutex_create(&wakeup->mutex, APR_THREAD_MUTEX_DEFAULT,
+ pool)) != APR_SUCCESS) {
+ return NULL;
+ }
+ /* The wakeup's mutex will be unlocked automatically when
+ * the worker blocks on the condition variable
+ */
+ apr_thread_mutex_lock(wakeup->mutex);
+ return wakeup;
+}
+
+
+/* Structure used to hold a stack of idle worker threads
+ */
+typedef struct {
+ /* 'state' consists of several fields concatenated into a
+ * single 32-bit int for use with the apr_atomic_cas() API:
+ * state & STACK_FIRST is the thread ID of the first thread
+ * in a linked list of idle threads
+ * state & STACK_TERMINATED indicates whether the proc is shutting down
+ * state & STACK_NO_LISTENER indicates whether the process has
+ * no current listener thread
+ */
+ apr_uint32_t state;
+} worker_stack;
+
+#define STACK_FIRST 0xffff
+#define STACK_LIST_END 0xffff
+#define STACK_TERMINATED 0x10000
+#define STACK_NO_LISTENER 0x20000
+
+static worker_wakeup_info **worker_wakeups = NULL;
+
+static worker_stack* worker_stack_create(apr_pool_t *pool, apr_size_t max)
+{
+ worker_stack *stack = (worker_stack *)apr_palloc(pool, sizeof(*stack));
+ stack->state = STACK_NO_LISTENER | STACK_LIST_END;
+ return stack;
+}
+
+static apr_status_t worker_stack_wait(worker_stack *stack,
+ apr_uint32_t worker_id)
+{
+ worker_wakeup_info *wakeup = worker_wakeups[worker_id];
+
+ while (1) {
+ apr_uint32_t state = stack->state;
+ if (state & (STACK_TERMINATED | STACK_NO_LISTENER)) {
+ if (state & STACK_TERMINATED) {
+ return APR_EINVAL;
+ }
+ if (apr_atomic_cas(&(stack->state), STACK_LIST_END, state) !=
+ state) {
+ continue;
+ }
+ else {
+ return APR_SUCCESS;
+ }
+ }
+ wakeup->next = state;
+ if (apr_atomic_cas(&(stack->state), worker_id, state) != state) {
+ continue;
+ }
+ else {
+ return apr_thread_cond_wait(wakeup->cond, wakeup->mutex);
+ }
+ }
+}
+
+static apr_status_t worker_stack_awaken_next(worker_stack *stack)
+{
+
+ while (1) {
+ apr_uint32_t state = stack->state;
+ apr_uint32_t first = state & STACK_FIRST;
+ if (first == STACK_LIST_END) {
+ if (apr_atomic_cas(&(stack->state), state | STACK_NO_LISTENER,
+ state) != state) {
+ continue;
+ }
+ else {
+ return APR_SUCCESS;
+ }
+ }
+ else {
+ worker_wakeup_info *wakeup = worker_wakeups[first];
+ if (apr_atomic_cas(&(stack->state), (state ^ first) | wakeup->next,
+ state) != state) {
+ continue;
+ }
+ else {
+ /* Acquire and release the idle worker's mutex to ensure
+ * that it's actually waiting on its condition variable
+ */
+ apr_status_t rv;
+ if ((rv = apr_thread_mutex_lock(wakeup->mutex)) !=
+ APR_SUCCESS) {
+ return rv;
+ }
+ if ((rv = apr_thread_mutex_unlock(wakeup->mutex)) !=
+ APR_SUCCESS) {
+ return rv;
+ }
+ return apr_thread_cond_signal(wakeup->cond);
+ }
+ }
+ }
+}
+
+static apr_status_t worker_stack_term(worker_stack *stack)
+{
+ int i;
+ apr_status_t rv;
+
+ while (1) {
+ apr_uint32_t state = stack->state;
+ if (apr_atomic_cas(&(stack->state), state | STACK_TERMINATED,
+ state) == state) {
+ break;
+ }
+ }
+ for (i = 0; i < ap_threads_per_child; i++) {
+ if ((rv = worker_stack_awaken_next(stack)) != APR_SUCCESS) {
+ return rv;
+ }
+ }
+ return APR_SUCCESS;
+}
+
+static worker_stack *idle_worker_stack;
+
+#define ST_INIT 0
+#define ST_GRACEFUL 1
+#define ST_UNGRACEFUL 2
+
+static int terminate_mode = ST_INIT;
+
+static void signal_threads(int mode)
+{
+ if (terminate_mode == mode) {
+ return;
+ }
+ terminate_mode = mode;
+ mpm_state = AP_MPMQ_STOPPING;
+ workers_may_exit = 1;
+
+ worker_stack_term(idle_worker_stack);
+}
+
+AP_DECLARE(apr_status_t) ap_mpm_query(int query_code, int *result)
+{
+ switch(query_code){
+ case AP_MPMQ_MAX_DAEMON_USED:
+ *result = ap_max_daemons_limit;
+ return APR_SUCCESS;
+ case AP_MPMQ_IS_THREADED:
+ *result = AP_MPMQ_STATIC;
+ return APR_SUCCESS;
+ case AP_MPMQ_IS_FORKED:
+ *result = AP_MPMQ_DYNAMIC;
+ return APR_SUCCESS;
+ case AP_MPMQ_HARD_LIMIT_DAEMONS:
+ *result = server_limit;
+ return APR_SUCCESS;
+ case AP_MPMQ_HARD_LIMIT_THREADS:
+ *result = thread_limit;
+ return APR_SUCCESS;
+ case AP_MPMQ_MAX_THREADS:
+ *result = ap_threads_per_child;
+ return APR_SUCCESS;
+ case AP_MPMQ_MIN_SPARE_DAEMONS:
+ *result = 0;
+ return APR_SUCCESS;
+ case AP_MPMQ_MIN_SPARE_THREADS:
+ *result = min_spare_threads;
+ return APR_SUCCESS;
+ case AP_MPMQ_MAX_SPARE_DAEMONS:
+ *result = 0;
+ return APR_SUCCESS;
+ case AP_MPMQ_MAX_SPARE_THREADS:
+ *result = max_spare_threads;
+ return APR_SUCCESS;
+ case AP_MPMQ_MAX_REQUESTS_DAEMON:
+ *result = ap_max_requests_per_child;
+ return APR_SUCCESS;
+ case AP_MPMQ_MAX_DAEMONS:
+ *result = ap_daemons_limit;
+ return APR_SUCCESS;
+ case AP_MPMQ_MPM_STATE:
+ *result = mpm_state;
+ return APR_SUCCESS;
+ }
+ return APR_ENOTIMPL;
+}
+
+/* a clean exit from a child with proper cleanup */
+static void clean_child_exit(int code) __attribute__ ((noreturn));
+static void clean_child_exit(int code)
+{
+ mpm_state = AP_MPMQ_STOPPING;
+ if (pchild) {
+ apr_pool_destroy(pchild);
+ }
+ ap_mpm_pod_close(pod);
+ exit(code);
+}
+
+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;
+static volatile int child_fatal;
+ap_generation_t volatile ap_my_generation;
+
+/*
+ * 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.
+ */
+
+static void ap_start_shutdown(void)
+{
+ mpm_state = AP_MPMQ_STOPPING;
+ 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 */
+static void ap_start_restart(int graceful)
+{
+ mpm_state = AP_MPMQ_STOPPING;
+ 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)
+{
+ if (ap_my_pid == parent_pid) {
+ ap_start_shutdown();
+ }
+ else {
+ signal_threads(ST_GRACEFUL);
+ }
+}
+
+static void restart(int sig)
+{
+ ap_start_restart(sig == AP_SIG_GRACEFUL);
+}
+
+static void set_signals(void)
+{
+#ifndef NO_USE_SIGACTION
+ struct sigaction sa;
+#endif
+
+ if (!one_process) {
+ ap_fatal_signal_setup(ap_server_conf, pconf);
+ }
+
+#ifndef NO_USE_SIGACTION
+ sigemptyset(&sa.sa_mask);
+ sa.sa_flags = 0;
+
+ sa.sa_handler = sig_term;
+ if (sigaction(SIGTERM, &sa, NULL) < 0)
+ ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf,
+ "sigaction(SIGTERM)");
+#ifdef SIGINT
+ if (sigaction(SIGINT, &sa, NULL) < 0)
+ ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_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, errno, ap_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, errno, ap_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, errno, ap_server_conf,
+ "sigaction(SIGPIPE)");
+#endif
+
+ /* we want to ignore HUPs and AP_SIG_GRACEFUL while we're busy
+ * processing one */
+ sigaddset(&sa.sa_mask, SIGHUP);
+ sigaddset(&sa.sa_mask, AP_SIG_GRACEFUL);
+ sa.sa_handler = restart;
+ if (sigaction(SIGHUP, &sa, NULL) < 0)
+ ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf,
+ "sigaction(SIGHUP)");
+ if (sigaction(AP_SIG_GRACEFUL, &sa, NULL) < 0)
+ ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf,
+ "sigaction(" AP_SIG_GRACEFUL_STRING ")");
+#else
+ if (!one_process) {
+#ifdef SIGXCPU
+ apr_signal(SIGXCPU, SIG_DFL);
+#endif /* SIGXCPU */
+#ifdef SIGXFSZ
+ apr_signal(SIGXFSZ, SIG_DFL);
+#endif /* SIGXFSZ */
+ }
+
+ apr_signal(SIGTERM, sig_term);
+#ifdef SIGHUP
+ apr_signal(SIGHUP, restart);
+#endif /* SIGHUP */
+#ifdef AP_SIG_GRACEFUL
+ apr_signal(AP_SIG_GRACEFUL, restart);
+#endif /* AP_SIG_GRACEFUL */
+#ifdef SIGPIPE
+ apr_signal(SIGPIPE, SIG_IGN);
+#endif /* SIGPIPE */
+
+#endif
+}
+
+/*****************************************************************
+ * Here follows a long bunch of generic server bookkeeping stuff...
+ */
+
+int ap_graceful_stop_signalled(void)
+ /* XXX this is really a bad confusing obsolete name
+ * maybe it should be ap_mpm_process_exiting?
+ */
+{
+ return workers_may_exit;
+}
+
+/*****************************************************************
+ * Child process main loop.
+ */
+
+static void process_socket(apr_pool_t *p, apr_socket_t *sock, int my_child_num,
+ int my_thread_num, apr_bucket_alloc_t *bucket_alloc)
+{
+ conn_rec *current_conn;
+ long conn_id = ID_FROM_CHILD_THREAD(my_child_num, my_thread_num);
+ int csd;
+ ap_sb_handle_t *sbh;
+
+ ap_create_sb_handle(&sbh, p, my_child_num, my_thread_num);
+ apr_os_sock_get(&csd, sock);
+
+ current_conn = ap_run_create_connection(p, ap_server_conf, sock,
+ conn_id, sbh, bucket_alloc);
+ if (current_conn) {
+ ap_process_connection(current_conn, sock);
+ ap_lingering_close(current_conn);
+ }
+}
+
+/* requests_this_child has gone to zero or below. See if the admin coded
+ "MaxRequestsPerChild 0", and keep going in that case. Doing it this way
+ simplifies the hot path in worker_thread */
+static void check_infinite_requests(void)
+{
+ if (ap_max_requests_per_child) {
+ signal_threads(ST_GRACEFUL);
+ }
+ else {
+ /* wow! if you're executing this code, you may have set a record.
+ * either this child process has served over 2 billion requests, or
+ * you're running a threaded 2.0 on a 16 bit machine.
+ *
+ * I'll buy pizza and beers at Apachecon for the first person to do
+ * the former without cheating (dorking with INT_MAX, or running with
+ * uncommitted performance patches, for example).
+ *
+ * for the latter case, you probably deserve a beer too. Greg Ames
+ */
+
+ requests_this_child = INT_MAX; /* keep going */
+ }
+}
+
+static void unblock_signal(int sig)
+{
+ sigset_t sig_mask;
+
+ sigemptyset(&sig_mask);
+ sigaddset(&sig_mask, sig);
+#if defined(SIGPROCMASK_SETS_THREAD_MASK)
+ sigprocmask(SIG_UNBLOCK, &sig_mask, NULL);
+#else
+ pthread_sigmask(SIG_UNBLOCK, &sig_mask, NULL);
+#endif
+}
+
+static void *worker_thread(apr_thread_t *thd, void * dummy)
+{
+ proc_info * ti = dummy;
+ int process_slot = ti->pid;
+ int thread_slot = ti->tid;
+ apr_uint32_t my_worker_num = (apr_uint32_t)(ti->tid);
+ apr_pool_t *tpool = apr_thread_pool_get(thd);
+ void *csd = NULL;
+ apr_allocator_t *allocator;
+ apr_pool_t *ptrans; /* Pool for per-transaction stuff */
+ apr_bucket_alloc_t *bucket_alloc;
+ int n;
+ apr_pollfd_t *pollset;
+ apr_status_t rv;
+ ap_listen_rec *lr, *last_lr = ap_listeners;
+ int is_listener;
+
+ ap_update_child_status_from_indexes(process_slot, thread_slot, SERVER_STARTING, NULL);
+
+ free(ti);
+
+ apr_allocator_create(&allocator);
+ apr_allocator_max_free_set(allocator, ap_max_mem_free);
+ /* XXX: why is ptrans's parent not tpool? --jcw 08/2003 */
+ apr_pool_create_ex(&ptrans, NULL, NULL, allocator);
+ apr_allocator_owner_set(allocator, ptrans);
+ bucket_alloc = apr_bucket_alloc_create_ex(allocator);
+
+ apr_poll_setup(&pollset, num_listensocks, tpool);
+ for(lr = ap_listeners ; lr != NULL ; lr = lr->next)
+ apr_poll_socket_add(pollset, lr->sd, APR_POLLIN);
+
+ /* TODO: Switch to a system where threads reuse the results from earlier
+ poll calls - manoj */
+ is_listener = 0;
+ while (!workers_may_exit) {
+
+ ap_update_child_status_from_indexes(process_slot, thread_slot,
+ SERVER_READY, NULL);
+ if (!is_listener) {
+ /* Wait until it's our turn to become the listener */
+ if ((rv = worker_stack_wait(idle_worker_stack, my_worker_num)) !=
+ APR_SUCCESS) {
+ if (rv != APR_EINVAL) {
+ ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf,
+ "worker_stack_wait failed. Shutting down");
+ }
+ break;
+ }
+ if (workers_may_exit) {
+ break;
+ }
+ is_listener = 1;
+ }
+
+ /* TODO: requests_this_child should be synchronized - aaron */
+ if (requests_this_child <= 0) {
+ check_infinite_requests();
+ }
+ if (workers_may_exit) break;
+
+ if ((rv = SAFE_ACCEPT(apr_proc_mutex_lock(accept_mutex)))
+ != APR_SUCCESS) {
+ int level = APLOG_EMERG;
+
+ if (workers_may_exit) {
+ break;
+ }
+ if (ap_scoreboard_image->parent[process_slot].generation !=
+ ap_scoreboard_image->global->running_generation) {
+ level = APLOG_DEBUG; /* common to get these at restart time */
+ }
+ ap_log_error(APLOG_MARK, level, rv, ap_server_conf,
+ "apr_proc_mutex_lock failed. Attempting to shutdown "
+ "process gracefully.");
+ signal_threads(ST_GRACEFUL);
+ break; /* skip the lock release */
+ }
+
+ if (!ap_listeners->next) {
+ /* Only one listener, so skip the poll */
+ lr = ap_listeners;
+ }
+ else {
+ while (!workers_may_exit) {
+ apr_status_t ret;
+ apr_int16_t event;
+
+ ret = apr_poll(pollset, num_listensocks, &n, -1);
+ if (ret != APR_SUCCESS) {
+ if (APR_STATUS_IS_EINTR(ret)) {
+ continue;
+ }
+
+ /* apr_poll() will only return errors in catastrophic
+ * circumstances. Let's try exiting gracefully, for now. */
+ ap_log_error(APLOG_MARK, APLOG_ERR, ret, (const server_rec *)
+ ap_server_conf, "apr_poll: (listen)");
+ signal_threads(ST_GRACEFUL);
+ }
+
+ if (workers_may_exit) break;
+
+ /* find a listener */
+ lr = last_lr;
+ do {
+ lr = lr->next;
+ if (lr == NULL) {
+ lr = ap_listeners;
+ }
+ /* XXX: Should we check for POLLERR? */
+ apr_poll_revents_get(&event, lr->sd, pollset);
+ if (event & APR_POLLIN) {
+ last_lr = lr;
+ goto got_fd;
+ }
+ } while (lr != last_lr);
+ }
+ }
+ got_fd:
+ if (!workers_may_exit) {
+ rv = lr->accept_func(&csd, lr, ptrans);
+ /* later we trash rv and rely on csd to indicate success/failure */
+ AP_DEBUG_ASSERT(rv == APR_SUCCESS || !csd);
+
+ if (rv == APR_EGENERAL) {
+ /* E[NM]FILE, ENOMEM, etc */
+ resource_shortage = 1;
+ signal_threads(ST_GRACEFUL);
+ }
+ if ((rv = SAFE_ACCEPT(apr_proc_mutex_unlock(accept_mutex)))
+ != APR_SUCCESS) {
+ int level = APLOG_EMERG;
+
+ if (workers_may_exit) {
+ break;
+ }
+ if (ap_scoreboard_image->parent[process_slot].generation !=
+ ap_scoreboard_image->global->running_generation) {
+ level = APLOG_DEBUG; /* common to get these at restart time */
+ }
+ ap_log_error(APLOG_MARK, level, rv, ap_server_conf,
+ "apr_proc_mutex_unlock failed. Attempting to "
+ "shutdown process gracefully.");
+ signal_threads(ST_GRACEFUL);
+ }
+ if (csd != NULL) {
+ is_listener = 0;
+ worker_stack_awaken_next(idle_worker_stack);
+ process_socket(ptrans, csd, process_slot,
+ thread_slot, bucket_alloc);
+ apr_pool_clear(ptrans);
+ requests_this_child--;
+ }
+ if ((ap_mpm_pod_check(pod) == APR_SUCCESS) ||
+ (ap_my_generation !=
+ ap_scoreboard_image->global->running_generation)) {
+ signal_threads(ST_GRACEFUL);
+ break;
+ }
+ }
+ else {
+ if ((rv = SAFE_ACCEPT(apr_proc_mutex_unlock(accept_mutex)))
+ != APR_SUCCESS) {
+ ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf,
+ "apr_proc_mutex_unlock failed. Attempting to "
+ "shutdown process gracefully.");
+ signal_threads(ST_GRACEFUL);
+ }
+ break;
+ }
+ }
+
+ dying = 1;
+ ap_scoreboard_image->parent[process_slot].quiescing = 1;
+
+ worker_stack_term(idle_worker_stack);
+
+ ap_update_child_status_from_indexes(process_slot, thread_slot,
+ (dying) ? SERVER_DEAD : SERVER_GRACEFUL, (request_rec *) NULL);
+
+ apr_bucket_alloc_destroy(bucket_alloc);
+
+ apr_thread_exit(thd, APR_SUCCESS);
+ return NULL;
+}
+
+static int check_signal(int signum)
+{
+ switch (signum) {
+ case SIGTERM:
+ case SIGINT:
+ return 1;
+ }
+ return 0;
+}
+
+/* XXX under some circumstances not understood, children can get stuck
+ * in start_threads forever trying to take over slots which will
+ * never be cleaned up; for now there is an APLOG_DEBUG message issued
+ * every so often when this condition occurs
+ */
+static void * APR_THREAD_FUNC start_threads(apr_thread_t *thd, void *dummy)
+{
+ thread_starter *ts = dummy;
+ apr_thread_t **threads = ts->threads;
+ apr_threadattr_t *thread_attr = ts->threadattr;
+ int child_num_arg = ts->child_num_arg;
+ int my_child_num = child_num_arg;
+ proc_info *my_info;
+ apr_status_t rv;
+ int i;
+ int threads_created = 0;
+ int loops;
+ int prev_threads_created;
+
+ idle_worker_stack = worker_stack_create(pchild, ap_threads_per_child);
+ if (idle_worker_stack == NULL) {
+ ap_log_error(APLOG_MARK, APLOG_ALERT, 0, ap_server_conf,
+ "worker_stack_create() failed");
+ clean_child_exit(APEXIT_CHILDFATAL);
+ }
+
+ worker_wakeups = (worker_wakeup_info **)
+ apr_palloc(pchild, sizeof(worker_wakeup_info *) *
+ ap_threads_per_child);
+
+ loops = prev_threads_created = 0;
+ while (1) {
+ for (i = 0; i < ap_threads_per_child; i++) {
+ int status = ap_scoreboard_image->servers[child_num_arg][i].status;
+ worker_wakeup_info *wakeup;
+
+ if (status != SERVER_GRACEFUL && status != SERVER_DEAD) {
+ continue;
+ }
+
+ wakeup = worker_wakeup_create(pchild);
+ if (wakeup == NULL) {
+ ap_log_error(APLOG_MARK, APLOG_ALERT|APLOG_NOERRNO, 0,
+ ap_server_conf, "worker_wakeup_create failed");
+ clean_child_exit(APEXIT_CHILDFATAL);
+ }
+ worker_wakeups[threads_created] = wakeup;
+ my_info = (proc_info *)malloc(sizeof(proc_info));
+ if (my_info == NULL) {
+ ap_log_error(APLOG_MARK, APLOG_ALERT, errno, ap_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;
+
+ /* We are creating threads right now */
+ ap_update_child_status_from_indexes(my_child_num, i,
+ SERVER_STARTING, NULL);
+ /* We let each thread update its own scoreboard entry. This is
+ * done because it lets us deal with tid better.
+ */
+ rv = apr_thread_create(&threads[i], thread_attr,
+ worker_thread, my_info, pchild);
+ if (rv != APR_SUCCESS) {
+ ap_log_error(APLOG_MARK, APLOG_ALERT, rv, ap_server_conf,
+ "apr_thread_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. */
+ apr_sleep(10 * APR_USEC_PER_SEC);
+ clean_child_exit(APEXIT_CHILDFATAL);
+ }
+ threads_created++;
+ }
+ if (start_thread_may_exit || threads_created == ap_threads_per_child) {
+ break;
+ }
+ /* wait for previous generation to clean up an entry */
+ apr_sleep(1 * APR_USEC_PER_SEC);
+ ++loops;
+ if (loops % 120 == 0) { /* every couple of minutes */
+ if (prev_threads_created == threads_created) {
+ ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf,
+ "child %" APR_PID_T_FMT " isn't taking over "
+ "slots very quickly (%d of %d)",
+ ap_my_pid, threads_created, ap_threads_per_child);
+ }
+ prev_threads_created = threads_created;
+ }
+ }
+
+ /* What state should this child_main process be listed as in the
+ * scoreboard...?
+ * ap_update_child_status_from_indexes(my_child_num, i, SERVER_STARTING,
+ * (request_rec *) NULL);
+ *
+ * This state should be listed separately in the scoreboard, in some kind
+ * of process_status, not mixed in with the worker threads' status.
+ * "life_status" is almost right, but it's in the worker's structure, and
+ * the name could be clearer. gla
+ */
+ apr_thread_exit(thd, APR_SUCCESS);
+ return NULL;
+}
+
+static void join_workers(apr_thread_t **threads)
+{
+ int i;
+ apr_status_t rv, thread_rv;
+
+ for (i = 0; i < ap_threads_per_child; i++) {
+ if (threads[i]) { /* if we ever created this thread */
+ rv = apr_thread_join(&thread_rv, threads[i]);
+ if (rv != APR_SUCCESS) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ap_server_conf,
+ "apr_thread_join: unable to join worker "
+ "thread %d",
+ i);
+ }
+ }
+ }
+}
+
+static void join_start_thread(apr_thread_t *start_thread_id)
+{
+ apr_status_t rv, thread_rv;
+
+ start_thread_may_exit = 1; /* tell it to give up in case it is still
+ * trying to take over slots from a
+ * previous generation
+ */
+ rv = apr_thread_join(&thread_rv, start_thread_id);
+ if (rv != APR_SUCCESS) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ap_server_conf,
+ "apr_thread_join: unable to join the start "
+ "thread");
+ }
+}
+
+static void child_main(int child_num_arg)
+{
+ apr_thread_t **threads;
+ apr_status_t rv;
+ thread_starter *ts;
+ apr_threadattr_t *thread_attr;
+ apr_thread_t *start_thread_id;
+
+ mpm_state = AP_MPMQ_STARTING; /* for benefit of any hooks that run as this
+ * child initializes
+ */
+
+ ap_my_pid = getpid();
+ ap_fatal_signal_child_setup(ap_server_conf);
+ apr_pool_create(&pchild, pconf);
+
+ /*stuff to do before we switch id's, so we have permissions.*/
+ ap_reopen_scoreboard(pchild, NULL, 0);
+
+ rv = SAFE_ACCEPT(apr_proc_mutex_child_init(&accept_mutex, ap_lock_fname,
+ pchild));
+ if (rv != APR_SUCCESS) {
+ ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf,
+ "Couldn't initialize cross-process lock in child");
+ clean_child_exit(APEXIT_CHILDFATAL);
+ }
+
+ if (unixd_setup_child()) {
+ clean_child_exit(APEXIT_CHILDFATAL);
+ }
+
+ ap_run_child_init(pchild, ap_server_conf);
+
+ /* done with init critical section */
+
+ /* Just use the standard apr_setup_signal_thread to block all signals
+ * from being received. The child processes no longer use signals for
+ * any communication with the parent process.
+ */
+ rv = apr_setup_signal_thread();
+ if (rv != APR_SUCCESS) {
+ ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf,
+ "Couldn't initialize signal thread");
+ clean_child_exit(APEXIT_CHILDFATAL);
+ }
+
+ if (ap_max_requests_per_child) {
+ requests_this_child = ap_max_requests_per_child;
+ }
+ else {
+ /* coding a value of zero means infinity */
+ requests_this_child = INT_MAX;
+ }
+
+ /* Setup worker threads */
+
+ /* clear the storage; we may not create all our threads immediately,
+ * and we want a 0 entry to indicate a thread which was not created
+ */
+ threads = (apr_thread_t **)calloc(1,
+ sizeof(apr_thread_t *) * ap_threads_per_child);
+ if (threads == NULL) {
+ ap_log_error(APLOG_MARK, APLOG_ALERT, errno, ap_server_conf,
+ "malloc: out of memory");
+ clean_child_exit(APEXIT_CHILDFATAL);
+ }
+
+ ts = (thread_starter *)apr_palloc(pchild, sizeof(*ts));
+
+ apr_threadattr_create(&thread_attr, pchild);
+ /* 0 means PTHREAD_CREATE_JOINABLE */
+ apr_threadattr_detach_set(thread_attr, 0);
+
+ ts->threads = threads;
+ ts->child_num_arg = child_num_arg;
+ ts->threadattr = thread_attr;
+
+ rv = apr_thread_create(&start_thread_id, thread_attr, start_threads,
+ ts, pchild);
+ if (rv != APR_SUCCESS) {
+ ap_log_error(APLOG_MARK, APLOG_ALERT, rv, ap_server_conf,
+ "apr_thread_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. */
+ apr_sleep(10 * APR_USEC_PER_SEC);
+ clean_child_exit(APEXIT_CHILDFATAL);
+ }
+
+ mpm_state = AP_MPMQ_RUNNING;
+
+ /* If we are only running in one_process mode, we will want to
+ * still handle signals. */
+ if (one_process) {
+ /* Block until we get a terminating signal. */
+ apr_signal_thread(check_signal);
+ /* make sure the start thread has finished; signal_threads()
+ * and join_workers() depend on that
+ */
+ /* XXX join_start_thread() won't be awakened if one of our
+ * threads encounters a critical error and attempts to
+ * shutdown this child
+ */
+ join_start_thread(start_thread_id);
+ signal_threads(ST_UNGRACEFUL); /* helps us terminate a little more
+ * quickly than the dispatch of the signal thread
+ * beats the Pipe of Death and the browsers
+ */
+ /* A terminating signal was received. Now join each of the
+ * workers to clean them up.
+ * If the worker already exited, then the join frees
+ * their resources and returns.
+ * If the worker hasn't exited, then this blocks until
+ * they have (then cleans up).
+ */
+ join_workers(threads);
+ }
+ else { /* !one_process */
+ /* remove SIGTERM from the set of blocked signals... if one of
+ * the other threads in the process needs to take us down
+ * (e.g., for MaxRequestsPerChild) it will send us SIGTERM
+ */
+ unblock_signal(SIGTERM);
+ join_start_thread(start_thread_id);
+ join_workers(threads);
+ }
+
+ free(threads);
+
+ clean_child_exit(resource_shortage ? APEXIT_CHILDSICK : 0);
+}
+
+static int make_child(server_rec *s, int slot)
+{
+ int pid;
+
+ if (slot + 1 > ap_max_daemons_limit) {
+ ap_max_daemons_limit = slot + 1;
+ }
+
+ if (one_process) {
+ set_signals();
+ ap_scoreboard_image->parent[slot].pid = getpid();
+ child_main(slot);
+ }
+
+ if ((pid = fork()) == -1) {
+ ap_log_error(APLOG_MARK, APLOG_ERR, errno, s,
+ "fork: Unable to fork new process");
+
+ /* fork didn't succeed. Fix the scoreboard or else
+ * it will say SERVER_STARTING forever and ever
+ */
+ ap_update_child_status_from_indexes(slot, 0, SERVER_DEAD, NULL);
+
+ /* 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. */
+ apr_sleep(10 * APR_USEC_PER_SEC);
+
+ return -1;
+ }
+
+ if (!pid) {
+#ifdef HAVE_BINDPROCESSOR
+ /* By default, AIX binds to a single processor. This bit unbinds
+ * children which will then bind to another CPU.
+ */
+ int status = bindprocessor(BINDPROCESS, (int)getpid(),
+ PROCESSOR_CLASS_ANY);
+ if (status != OK)
+ ap_log_error(APLOG_MARK, APLOG_WARNING, errno,
+ ap_server_conf,
+ "processor unbind failed %d", status);
+#endif
+ RAISE_SIGSTOP(MAKE_CHILD);
+
+ apr_signal(SIGTERM, just_die);
+ child_main(slot);
+
+ clean_child_exit(0);
+ }
+ /* else */
+ ap_scoreboard_image->parent[slot].quiescing = 0;
+ ap_scoreboard_image->parent[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_daemons_limit; ++i) {
+ if (ap_scoreboard_image->parent[i].pid != 0) {
+ continue;
+ }
+ if (make_child(ap_server_conf, i) < 0) {
+ break;
+ }
+ --number_to_start;
+ }
+}
+
+
+/*
+ * 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, j;
+ int idle_thread_count;
+ worker_score *ws;
+ process_score *ps;
+ int free_length;
+ int totally_free_length = 0;
+ int free_slots[MAX_SPAWN_RATE];
+ int last_non_dead;
+ int total_non_dead;
+
+ /* initialize the free_list */
+ free_length = 0;
+
+ idle_thread_count = 0;
+ last_non_dead = -1;
+ total_non_dead = 0;
+
+ for (i = 0; i < ap_daemons_limit; ++i) {
+ /* Initialization to satisfy the compiler. It doesn't know
+ * that ap_threads_per_child is always > 0 */
+ int status = SERVER_DEAD;
+ int any_dying_threads = 0;
+ int any_dead_threads = 0;
+ int all_dead_threads = 1;
+
+ if (i >= ap_max_daemons_limit && totally_free_length == idle_spawn_rate)
+ break;
+ ps = &ap_scoreboard_image->parent[i];
+ for (j = 0; j < ap_threads_per_child; j++) {
+ ws = &ap_scoreboard_image->servers[i][j];
+ status = ws->status;
+
+ /* XXX any_dying_threads is probably no longer needed GLA */
+ any_dying_threads = any_dying_threads ||
+ (status == SERVER_GRACEFUL);
+ any_dead_threads = any_dead_threads || (status == SERVER_DEAD);
+ all_dead_threads = all_dead_threads &&
+ (status == SERVER_DEAD ||
+ status == SERVER_GRACEFUL);
+
+ /* 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 && status != SERVER_DEAD &&
+ !ps->quiescing &&
+ ps->generation == ap_my_generation &&
+ /* XXX the following shouldn't be necessary if we clean up
+ * properly after seg faults, but we're not yet GLA
+ */
+ ps->pid != 0) {
+ ++idle_thread_count;
+ }
+ }
+ if (any_dead_threads && totally_free_length < idle_spawn_rate
+ && (!ps->pid /* no process in the slot */
+ || ps->quiescing)) { /* or at least one is going away */
+ if (all_dead_threads) {
+ /* great! we prefer these, because the new process can
+ * start more threads sooner. So prioritize this slot
+ * by putting it ahead of any slots with active threads.
+ *
+ * first, make room by moving a slot that's potentially still
+ * in use to the end of the array
+ */
+ free_slots[free_length] = free_slots[totally_free_length];
+ free_slots[totally_free_length++] = i;
+ }
+ else {
+ /* slot is still in use - back of the bus
+ */
+ free_slots[free_length] = i;
+ }
+ ++free_length;
+ }
+ /* XXX if (!ps->quiescing) is probably more reliable GLA */
+ if (!any_dying_threads) {
+ last_non_dead = i;
+ ++total_non_dead;
+ }
+ }
+ ap_max_daemons_limit = last_non_dead + 1;
+
+ if (idle_thread_count > max_spare_threads) {
+ /* Kill off one child */
+ ap_mpm_pod_signal(pod);
+ idle_spawn_rate = 1;
+ }
+ else if (idle_thread_count < min_spare_threads) {
+ /* terminate the free list */
+ if (free_length == 0) {
+ /* only report this condition once */
+ static int reported = 0;
+
+ if (!reported) {
+ ap_log_error(APLOG_MARK, APLOG_ERR, 0,
+ ap_server_conf,
+ "server reached MaxClients setting, consider"
+ " raising the MaxClients setting");
+ reported = 1;
+ }
+ idle_spawn_rate = 1;
+ }
+ else {
+ if (free_length > idle_spawn_rate) {
+ free_length = idle_spawn_rate;
+ }
+ if (idle_spawn_rate >= 8) {
+ ap_log_error(APLOG_MARK, APLOG_INFO, 0,
+ ap_server_conf,
+ "server seems busy, (you may need "
+ "to increase StartServers, ThreadsPerChild "
+ "or Min/MaxSpareThreads), "
+ "spawning %d children, there are around %d idle "
+ "threads, and %d total children", free_length,
+ idle_thread_count, total_non_dead);
+ }
+ for (i = 0; i < free_length; ++i) {
+ make_child(ap_server_conf, free_slots[i]);
+ }
+ /* 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 (idle_spawn_rate < MAX_SPAWN_RATE) {
+ idle_spawn_rate *= 2;
+ }
+ }
+ }
+ else {
+ idle_spawn_rate = 1;
+ }
+}
+
+static void server_main_loop(int remaining_children_to_start)
+{
+ int child_slot;
+ apr_exit_why_e exitwhy;
+ int status, processed_status;
+ apr_proc_t pid;
+ int i;
+
+ while (!restart_pending && !shutdown_pending) {
+ ap_wait_or_timeout(&exitwhy, &status, &pid, pconf);
+
+ if (pid.pid != -1) {
+ processed_status = ap_process_child_status(&pid, exitwhy, status);
+ if (processed_status == APEXIT_CHILDFATAL) {
+ shutdown_pending = 1;
+ child_fatal = 1;
+ return;
+ }
+ /* non-fatal death... note that it's gone in the scoreboard. */
+ child_slot = find_child_by_pid(&pid);
+ if (child_slot >= 0) {
+ for (i = 0; i < ap_threads_per_child; i++)
+ ap_update_child_status_from_indexes(child_slot, i, SERVER_DEAD,
+ (request_rec *) NULL);
+
+ ap_scoreboard_image->parent[child_slot].pid = 0;
+ ap_scoreboard_image->parent[child_slot].quiescing = 0;
+ if (processed_status == APEXIT_CHILDSICK) {
+ /* resource shortage, minimize the fork rate */
+ idle_spawn_rate = 1;
+ }
+ else if (remaining_children_to_start
+ && child_slot < ap_daemons_limit) {
+ /* we're still doing a 1-for-1 replacement of dead
+ * children with new children
+ */
+ make_child(ap_server_conf, child_slot);
+ --remaining_children_to_start;
+ }
+#if APR_HAS_OTHER_CHILD
+ }
+ else if (apr_proc_other_child_read(&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_WARNING, 0,
+ ap_server_conf,
+ "long lost child came home! (pid %ld)",
+ (long)pid.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_idle_server_maintenance();
+ }
+}
+
+int ap_mpm_run(apr_pool_t *_pconf, apr_pool_t *plog, server_rec *s)
+{
+ int remaining_children_to_start;
+ apr_status_t rv;
+
+ ap_log_pid(pconf, ap_pid_fname);
+
+ first_server_limit = server_limit;
+ first_thread_limit = thread_limit;
+ if (changed_limit_at_restart) {
+ ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s,
+ "WARNING: Attempt to change ServerLimit or ThreadLimit "
+ "ignored during restart");
+ changed_limit_at_restart = 0;
+ }
+
+ /* Initialize cross-process accept lock */
+ ap_lock_fname = apr_psprintf(_pconf, "%s.%" APR_PID_T_FMT,
+ ap_server_root_relative(_pconf, ap_lock_fname),
+ ap_my_pid);
+
+ rv = apr_proc_mutex_create(&accept_mutex, ap_lock_fname,
+ ap_accept_lock_mech, _pconf);
+ if (rv != APR_SUCCESS) {
+ ap_log_error(APLOG_MARK, APLOG_EMERG, rv, s,
+ "Couldn't create accept lock");
+ mpm_state = AP_MPMQ_STOPPING;
+ return 1;
+ }
+
+#if APR_USE_SYSVSEM_SERIALIZE
+ if (ap_accept_lock_mech == APR_LOCK_DEFAULT ||
+ ap_accept_lock_mech == APR_LOCK_SYSVSEM) {
+#else
+ if (ap_accept_lock_mech == APR_LOCK_SYSVSEM) {
+#endif
+ rv = unixd_set_proc_mutex_perms(accept_mutex);
+ if (rv != APR_SUCCESS) {
+ ap_log_error(APLOG_MARK, APLOG_EMERG, rv, s,
+ "Couldn't set permissions on cross-process lock; "
+ "check User and Group directives");
+ mpm_state = AP_MPMQ_STOPPING;
+ return 1;
+ }
+ }
+
+ if (!is_graceful) {
+ if (ap_run_pre_mpm(s->process->pool, SB_SHARED) != OK) {
+ mpm_state = AP_MPMQ_STOPPING;
+ return 1;
+ }
+ /* fix the generation number in the global score; we just got a new,
+ * cleared scoreboard
+ */
+ ap_scoreboard_image->global->running_generation = ap_my_generation;
+ }
+
+ set_signals();
+ /* Don't thrash... */
+ if (max_spare_threads < min_spare_threads + ap_threads_per_child)
+ max_spare_threads = min_spare_threads + ap_threads_per_child;
+
+ /* 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 AP_SIG_GRACEFUL). 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_daemons_to_start;
+ if (remaining_children_to_start > ap_daemons_limit) {
+ remaining_children_to_start = ap_daemons_limit;
+ }
+ 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_NOTICE, 0, ap_server_conf,
+ "%s configured -- resuming normal operations",
+ ap_get_server_version());
+ ap_log_error(APLOG_MARK, APLOG_INFO, 0, ap_server_conf,
+ "Server built: %s", ap_get_server_built());
+#ifdef AP_MPM_WANT_SET_ACCEPT_LOCK_MECH
+ ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf,
+ "AcceptMutex: %s (default: %s)",
+ apr_proc_mutex_name(accept_mutex),
+ apr_proc_mutex_defname());
+#endif
+ restart_pending = shutdown_pending = 0;
+ mpm_state = AP_MPMQ_RUNNING;
+
+ server_main_loop(remaining_children_to_start);
+ mpm_state = AP_MPMQ_STOPPING;
+
+ if (shutdown_pending) {
+ /* Time to gracefully shut down:
+ * Kill child processes, tell them to call child_exit, etc...
+ * (By "gracefully" we don't mean graceful in the same sense as
+ * "apachectl graceful" where we allow old connections to finish.)
+ */
+ if (unixd_killpg(getpgrp(), SIGTERM) < 0) {
+ ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "killpg SIGTERM");
+ }
+ ap_reclaim_child_processes(1); /* Start with SIGTERM */
+
+ if (!child_fatal) {
+ /* 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_INFO, 0,
+ ap_server_conf,
+ "removed PID file %s (pid=%ld)",
+ pidfile, (long)getpid());
+
+ ap_log_error(APLOG_MARK, APLOG_NOTICE, 0,
+ ap_server_conf, "caught SIGTERM, shutting down");
+ }
+ return 1;
+ }
+
+ /* we've been told to restart */
+ apr_signal(SIGHUP, SIG_IGN);
+
+ 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.
+ */
+ ++ap_my_generation;
+ ap_scoreboard_image->global->running_generation = ap_my_generation;
+
+ if (is_graceful) {
+ ap_log_error(APLOG_MARK, APLOG_NOTICE, 0, ap_server_conf,
+ AP_SIG_GRACEFUL_STRING " received. Doing graceful restart");
+ /* wake up the children...time to die. But we'll have more soon */
+ ap_mpm_pod_killpg(pod, ap_daemons_limit);
+
+
+ /* This is mostly for debugging... so that we know what is still
+ * gracefully dealing with existing request.
+ */
+
+ }
+ 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.
+ */
+ ap_mpm_pod_killpg(pod, ap_daemons_limit);
+
+ ap_reclaim_child_processes(1); /* Start with SIGTERM */
+ ap_log_error(APLOG_MARK, APLOG_NOTICE, 0, ap_server_conf,
+ "SIGHUP received. Attempting to restart");
+ }
+
+ return 0;
+}
+
+/* This really should be a post_config hook, but the error log is already
+ * redirected by that point, so we need to do this in the open_logs phase.
+ */
+static int leader_open_logs(apr_pool_t *p, apr_pool_t *plog, apr_pool_t *ptemp, server_rec *s)
+{
+ apr_status_t rv;
+
+ pconf = p;
+ ap_server_conf = s;
+
+ if ((num_listensocks = ap_setup_listeners(ap_server_conf)) < 1) {
+ ap_log_error(APLOG_MARK, APLOG_ALERT|APLOG_STARTUP, 0,
+ NULL, "no listening sockets available, shutting down");
+ return DONE;
+ }
+
+ if (!one_process) {
+ if ((rv = ap_mpm_pod_open(pconf, &pod))) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT|APLOG_STARTUP, rv, NULL,
+ "Could not open pipe-of-death.");
+ return DONE;
+ }
+ }
+ return OK;
+}
+
+static int leader_pre_config(apr_pool_t *pconf, apr_pool_t *plog,
+ apr_pool_t *ptemp)
+{
+ static int restart_num = 0;
+ int no_detach, debug, foreground;
+ ap_directive_t *pdir;
+ ap_directive_t *max_clients = NULL;
+ apr_status_t rv;
+
+ mpm_state = AP_MPMQ_STARTING;
+
+ /* make sure that "ThreadsPerChild" gets set before "MaxClients" */
+ for (pdir = ap_conftree; pdir != NULL; pdir = pdir->next) {
+ if (strncasecmp(pdir->directive, "ThreadsPerChild", 15) == 0) {
+ if (!max_clients) {
+ break; /* we're in the clear, got ThreadsPerChild first */
+ }
+ else {
+ /* now to swap the data */
+ ap_directive_t temp;
+
+ temp.directive = pdir->directive;
+ temp.args = pdir->args;
+ /* Make sure you don't change 'next', or you may get loops! */
+ /* XXX: first_child, parent, and data can never be set
+ * for these directives, right? -aaron */
+ temp.filename = pdir->filename;
+ temp.line_num = pdir->line_num;
+
+ pdir->directive = max_clients->directive;
+ pdir->args = max_clients->args;
+ pdir->filename = max_clients->filename;
+ pdir->line_num = max_clients->line_num;
+
+ max_clients->directive = temp.directive;
+ max_clients->args = temp.args;
+ max_clients->filename = temp.filename;
+ max_clients->line_num = temp.line_num;
+ break;
+ }
+ }
+ else if (!max_clients
+ && strncasecmp(pdir->directive, "MaxClients", 10) == 0) {
+ max_clients = pdir;
+ }
+ }
+
+ debug = ap_exists_config_define("DEBUG");
+
+ if (debug) {
+ foreground = one_process = 1;
+ no_detach = 0;
+ }
+ else {
+ one_process = ap_exists_config_define("ONE_PROCESS");
+ no_detach = ap_exists_config_define("NO_DETACH");
+ foreground = ap_exists_config_define("FOREGROUND");
+ }
+
+ /* sigh, want this only the second time around */
+ if (restart_num++ == 1) {
+ is_graceful = 0;
+
+ if (!one_process && !foreground) {
+ rv = apr_proc_detach(no_detach ? APR_PROC_DETACH_FOREGROUND
+ : APR_PROC_DETACH_DAEMONIZE);
+ if (rv != APR_SUCCESS) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, NULL,
+ "apr_proc_detach failed");
+ return HTTP_INTERNAL_SERVER_ERROR;
+ }
+ }
+ parent_pid = ap_my_pid = getpid();
+ }
+
+ unixd_pre_config(ptemp);
+ ap_listen_pre_config();
+ ap_daemons_to_start = DEFAULT_START_DAEMON;
+ min_spare_threads = DEFAULT_MIN_FREE_DAEMON * DEFAULT_THREADS_PER_CHILD;
+ max_spare_threads = DEFAULT_MAX_FREE_DAEMON * DEFAULT_THREADS_PER_CHILD;
+ ap_daemons_limit = 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;
+#ifdef AP_MPM_WANT_SET_MAX_MEM_FREE
+ ap_max_mem_free = APR_ALLOCATOR_MAX_FREE_UNLIMITED;
+#endif
+
+ apr_cpystrn(ap_coredump_dir, ap_server_root, sizeof(ap_coredump_dir));
+
+ return OK;
+}
+
+static void leader_hooks(apr_pool_t *p)
+{
+ /* The leader open_logs phase must run before the core's, or stderr
+ * will be redirected to a file, and the messages won't print to the
+ * console.
+ */
+ static const char *const aszSucc[] = {"core.c", NULL};
+ one_process = 0;
+
+ ap_hook_open_logs(leader_open_logs, NULL, aszSucc, APR_HOOK_MIDDLE);
+ /* we need to set the MPM state before other pre-config hooks use MPM query
+ * to retrieve it, so register as REALLY_FIRST
+ */
+ ap_hook_pre_config(leader_pre_config, NULL, NULL, APR_HOOK_REALLY_FIRST);
+}
+
+static const char *set_daemons_to_start(cmd_parms *cmd, void *dummy,
+ const char *arg)
+{
+ const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
+ if (err != NULL) {
+ return err;
+ }
+
+ ap_daemons_to_start = atoi(arg);
+ return NULL;
+}
+
+static const char *set_min_spare_threads(cmd_parms *cmd, void *dummy,
+ const char *arg)
+{
+ const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
+ if (err != NULL) {
+ return err;
+ }
+
+ min_spare_threads = atoi(arg);
+ if (min_spare_threads <= 0) {
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ "WARNING: detected MinSpareThreads set to non-positive.");
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ "Resetting to 1 to avoid almost certain Apache failure.");
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ "Please read the documentation.");
+ min_spare_threads = 1;
+ }
+
+ return NULL;
+}
+
+static const char *set_max_spare_threads(cmd_parms *cmd, void *dummy,
+ const char *arg)
+{
+ const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
+ if (err != NULL) {
+ return err;
+ }
+
+ max_spare_threads = atoi(arg);
+ return NULL;
+}
+
+static const char *set_max_clients (cmd_parms *cmd, void *dummy,
+ const char *arg)
+{
+ int max_clients;
+ const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
+ if (err != NULL) {
+ return err;
+ }
+
+ /* It is ok to use ap_threads_per_child here because we are
+ * sure that it gets set before MaxClients in the pre_config stage. */
+ max_clients = atoi(arg);
+ if (max_clients < ap_threads_per_child) {
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ "WARNING: MaxClients (%d) must be at least as large",
+ max_clients);
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ " large as ThreadsPerChild (%d). Automatically",
+ ap_threads_per_child);
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ " increasing MaxClients to %d.",
+ ap_threads_per_child);
+ max_clients = ap_threads_per_child;
+ }
+ ap_daemons_limit = max_clients / ap_threads_per_child;
+ if ((max_clients > 0) && (max_clients % ap_threads_per_child)) {
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ "WARNING: MaxClients (%d) is not an integer multiple",
+ max_clients);
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ " of ThreadsPerChild (%d), lowering MaxClients to %d",
+ ap_threads_per_child,
+ ap_daemons_limit * ap_threads_per_child);
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ " for a maximum of %d child processes,",
+ ap_daemons_limit);
+ max_clients = ap_daemons_limit * ap_threads_per_child;
+ }
+ if (ap_daemons_limit > server_limit) {
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ "WARNING: MaxClients of %d would require %d servers,",
+ max_clients, ap_daemons_limit);
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ " and would exceed the ServerLimit value of %d.",
+ server_limit);
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ " Automatically lowering MaxClients to %d. To increase,",
+ server_limit * ap_threads_per_child);
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ " please see the ServerLimit directive.");
+ ap_daemons_limit = server_limit;
+ }
+ else if (ap_daemons_limit < 1) {
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ "WARNING: Require MaxClients > 0, setting to 1");
+ ap_daemons_limit = 1;
+ }
+ return NULL;
+}
+
+static const char *set_threads_per_child (cmd_parms *cmd, void *dummy,
+ const 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 > thread_limit) {
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ "WARNING: ThreadsPerChild of %d exceeds ThreadLimit "
+ "value of %d", ap_threads_per_child,
+ thread_limit);
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ "threads, lowering ThreadsPerChild to %d. To increase, please"
+ " see the", thread_limit);
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ " ThreadLimit directive.");
+ ap_threads_per_child = thread_limit;
+ }
+ else if (ap_threads_per_child < 1) {
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ "WARNING: Require ThreadsPerChild > 0, setting to 1");
+ ap_threads_per_child = 1;
+ }
+ return NULL;
+}
+
+static const char *set_server_limit (cmd_parms *cmd, void *dummy, const char *arg)
+{
+ int tmp_server_limit;
+
+ const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
+ if (err != NULL) {
+ return err;
+ }
+
+ tmp_server_limit = atoi(arg);
+ /* you cannot change ServerLimit across a restart; ignore
+ * any such attempts
+ */
+ if (first_server_limit &&
+ tmp_server_limit != server_limit) {
+ /* how do we log a message? the error log is a bit bucket at this
+ * point; we'll just have to set a flag so that ap_mpm_run()
+ * logs a warning later
+ */
+ changed_limit_at_restart = 1;
+ return NULL;
+ }
+ server_limit = tmp_server_limit;
+
+ if (server_limit > MAX_SERVER_LIMIT) {
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ "WARNING: ServerLimit of %d exceeds compile time limit "
+ "of %d servers,", server_limit, MAX_SERVER_LIMIT);
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ " lowering ServerLimit to %d.", MAX_SERVER_LIMIT);
+ server_limit = MAX_SERVER_LIMIT;
+ }
+ else if (server_limit < 1) {
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ "WARNING: Require ServerLimit > 0, setting to 1");
+ server_limit = 1;
+ }
+ return NULL;
+}
+
+static const char *set_thread_limit (cmd_parms *cmd, void *dummy, const char *arg)
+{
+ int tmp_thread_limit;
+
+ const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
+ if (err != NULL) {
+ return err;
+ }
+
+ tmp_thread_limit = atoi(arg);
+ /* you cannot change ThreadLimit across a restart; ignore
+ * any such attempts
+ */
+ if (first_thread_limit &&
+ tmp_thread_limit != thread_limit) {
+ /* how do we log a message? the error log is a bit bucket at this
+ * point; we'll just have to set a flag so that ap_mpm_run()
+ * logs a warning later
+ */
+ changed_limit_at_restart = 1;
+ return NULL;
+ }
+ thread_limit = tmp_thread_limit;
+
+ if (thread_limit > MAX_THREAD_LIMIT) {
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ "WARNING: ThreadLimit of %d exceeds compile time limit "
+ "of %d servers,", thread_limit, MAX_THREAD_LIMIT);
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ " lowering ThreadLimit to %d.", MAX_THREAD_LIMIT);
+ thread_limit = MAX_THREAD_LIMIT;
+ }
+ else if (thread_limit < 1) {
+ ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+ "WARNING: Require ThreadLimit > 0, setting to 1");
+ thread_limit = 1;
+ }
+ return NULL;
+}
+
+static const command_rec leader_cmds[] = {
+UNIX_DAEMON_COMMANDS,
+LISTEN_COMMANDS,
+AP_INIT_TAKE1("StartServers", set_daemons_to_start, NULL, RSRC_CONF,
+ "Number of child processes launched at server startup"),
+AP_INIT_TAKE1("MinSpareThreads", set_min_spare_threads, NULL, RSRC_CONF,
+ "Minimum number of idle children, to handle request spikes"),
+AP_INIT_TAKE1("MaxSpareThreads", set_max_spare_threads, NULL, RSRC_CONF,
+ "Maximum number of idle children"),
+AP_INIT_TAKE1("MaxClients", set_max_clients, NULL, RSRC_CONF,
+ "Maximum number of children alive at the same time"),
+AP_INIT_TAKE1("ThreadsPerChild", set_threads_per_child, NULL, RSRC_CONF,
+ "Number of threads each child creates"),
+AP_INIT_TAKE1("ServerLimit", set_server_limit, NULL, RSRC_CONF,
+ "Maximum value of MaxClients for this run of Apache"),
+AP_INIT_TAKE1("ThreadLimit", set_thread_limit, NULL, RSRC_CONF,
+ "Maximum worker threads in a server for this run of Apache"),
+{ NULL }
+};
+
+module AP_MODULE_DECLARE_DATA mpm_leader_module = {
+ MPM20_MODULE_STUFF,
+ ap_mpm_rewrite_args, /* hook to run before apache parses args */
+ NULL, /* create per-directory config structure */
+ NULL, /* merge per-directory config structures */
+ NULL, /* create per-server config structure */
+ NULL, /* merge per-server config structures */
+ leader_cmds, /* command apr_table_t */
+ leader_hooks /* register_hooks */
+};
+