mpm_common.c revision f5f279e2a6995267cc1a91165c1137e828d490b1
/* 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.
*/
/* The purpose of this file is to store the code that MOST mpm's will need
* this does not mean a function only goes into this file if every MPM needs
* it. It means that if a function is needed by more than one MPM, and
* future maintenance would be served by making the code common, then the
* function belongs here.
*
* This is going in src/main because it is not platform specific, it is
* specific to multi-process servers, but NOT to Unix. Which is why it
* does not belong in src/os/unix
*/
#include "apr.h"
#include "apr_thread_proc.h"
#include "apr_signal.h"
#include "apr_strings.h"
#define APR_WANT_STRFUNC
#include "apr_want.h"
#include "apr_getopt.h"
#include "apr_optional.h"
#include "apr_allocator.h"
#include "httpd.h"
#include "http_config.h"
#include "http_log.h"
#include "http_main.h"
#include "mpm.h"
#include "mpm_common.h"
#include "ap_mpm.h"
#include "ap_listen.h"
#include "mpm_default.h"
#include "util_mutex.h"
#ifdef AP_MPM_WANT_SET_SCOREBOARD
#include "scoreboard.h"
#endif
#ifdef HAVE_PWD_H
#include <pwd.h>
#endif
#ifdef HAVE_GRP_H
#include <grp.h>
#endif
#if APR_HAVE_UNISTD_H
#include <unistd.h>
#endif
#if AP_ENABLE_EXCEPTION_HOOK
APR_HOOK_STRUCT(
APR_HOOK_LINK(fatal_exception)
APR_HOOK_LINK(monitor)
)
AP_IMPLEMENT_HOOK_RUN_ALL(int, fatal_exception,
(ap_exception_info_t *ei), (ei), OK, DECLINED)
#else
APR_HOOK_STRUCT(
APR_HOOK_LINK(monitor)
)
#endif
AP_IMPLEMENT_HOOK_RUN_ALL(int, monitor,
(apr_pool_t *p), (p), OK, DECLINED)
#ifdef AP_MPM_WANT_RECLAIM_CHILD_PROCESSES
typedef enum {DO_NOTHING, SEND_SIGTERM, SEND_SIGKILL, GIVEUP} action_t;
typedef struct extra_process_t {
struct extra_process_t *next;
pid_t pid;
} extra_process_t;
static extra_process_t *extras;
void ap_register_extra_mpm_process(pid_t pid)
{
extra_process_t *p = (extra_process_t *)malloc(sizeof(extra_process_t));
p->next = extras;
p->pid = pid;
extras = p;
}
int ap_unregister_extra_mpm_process(pid_t pid)
{
extra_process_t *cur = extras;
extra_process_t *prev = NULL;
while (cur && cur->pid != pid) {
prev = cur;
cur = cur->next;
}
if (cur) {
if (prev) {
prev->next = cur->next;
}
else {
extras = cur->next;
}
free(cur);
return 1; /* found */
}
else {
/* we don't know about any such process */
return 0;
}
}
static int reclaim_one_pid(pid_t pid, action_t action)
{
apr_proc_t proc;
apr_status_t waitret;
proc.pid = pid;
waitret = apr_proc_wait(&proc, NULL, NULL, APR_NOWAIT);
if (waitret != APR_CHILD_NOTDONE) {
return 1;
}
switch(action) {
case DO_NOTHING:
break;
case SEND_SIGTERM:
/* ok, now it's being annoying */
ap_log_error(APLOG_MARK, APLOG_WARNING,
0, ap_server_conf,
"child process %" APR_PID_T_FMT
" still did not exit, "
"sending a SIGTERM",
pid);
kill(pid, SIGTERM);
break;
case SEND_SIGKILL:
ap_log_error(APLOG_MARK, APLOG_ERR,
0, ap_server_conf,
"child process %" APR_PID_T_FMT
" still did not exit, "
"sending a SIGKILL",
pid);
#ifndef BEOS
kill(pid, SIGKILL);
#else
/* sending a SIGKILL kills the entire team on BeOS, and as
* httpd thread is part of that team it removes any chance
* of ever doing a restart. To counter this I'm changing to
* use a kinder, gentler way of killing a specific thread
* that is just as effective.
*/
kill_thread(pid);
#endif
break;
case GIVEUP:
/* gave it our best shot, but alas... If this really
* is a child we are trying to kill and it really hasn't
* exited, we will likely fail to bind to the port
* after the restart.
*/
ap_log_error(APLOG_MARK, APLOG_ERR,
0, ap_server_conf,
"could not make child process %" APR_PID_T_FMT
" exit, "
"attempting to continue anyway",
pid);
break;
}
return 0;
}
void ap_reclaim_child_processes(int terminate)
{
apr_time_t waittime = 1024 * 16;
int i;
extra_process_t *cur_extra;
int not_dead_yet;
int max_daemons;
apr_time_t starttime = apr_time_now();
/* this table of actions and elapsed times tells what action is taken
* at which elapsed time from starting the reclaim
*/
struct {
action_t action;
apr_time_t action_time;
} action_table[] = {
{DO_NOTHING, 0}, /* dummy entry for iterations where we reap
* children but take no action against
* stragglers
*/
{SEND_SIGTERM, apr_time_from_sec(3)},
{SEND_SIGTERM, apr_time_from_sec(5)},
{SEND_SIGTERM, apr_time_from_sec(7)},
{SEND_SIGKILL, apr_time_from_sec(9)},
{GIVEUP, apr_time_from_sec(10)}
};
int cur_action; /* index of action we decided to take this
* iteration
*/
int next_action = 1; /* index of first real action */
ap_mpm_query(AP_MPMQ_MAX_DAEMON_USED, &max_daemons);
do {
apr_sleep(waittime);
/* don't let waittime get longer than 1 second; otherwise, we don't
* react quickly to the last child exiting, and taking action can
* be delayed
*/
waittime = waittime * 4;
if (waittime > apr_time_from_sec(1)) {
waittime = apr_time_from_sec(1);
}
/* see what action to take, if any */
if (action_table[next_action].action_time <= apr_time_now() - starttime) {
cur_action = next_action;
++next_action;
}
else {
cur_action = 0; /* nothing to do */
}
/* now see who is done */
not_dead_yet = 0;
for (i = 0; i < max_daemons; ++i) {
pid_t pid = MPM_CHILD_PID(i);
if (pid == 0) {
continue; /* not every scoreboard entry is in use */
}
if (reclaim_one_pid(pid, action_table[cur_action].action)) {
MPM_NOTE_CHILD_KILLED(i);
}
else {
++not_dead_yet;
}
}
cur_extra = extras;
while (cur_extra) {
extra_process_t *next = cur_extra->next;
if (reclaim_one_pid(cur_extra->pid, action_table[cur_action].action)) {
AP_DEBUG_ASSERT(1 == ap_unregister_extra_mpm_process(cur_extra->pid));
}
else {
++not_dead_yet;
}
cur_extra = next;
}
#if APR_HAS_OTHER_CHILD
apr_proc_other_child_refresh_all(APR_OC_REASON_RESTART);
#endif
} while (not_dead_yet > 0 &&
action_table[cur_action].action != GIVEUP);
}
void ap_relieve_child_processes(void)
{
int i;
extra_process_t *cur_extra;
int max_daemons;
ap_mpm_query(AP_MPMQ_MAX_DAEMON_USED, &max_daemons);
/* now see who is done */
for (i = 0; i < max_daemons; ++i) {
pid_t pid = MPM_CHILD_PID(i);
if (pid == 0) {
continue; /* not every scoreboard entry is in use */
}
if (reclaim_one_pid(pid, DO_NOTHING)) {
MPM_NOTE_CHILD_KILLED(i);
}
}
cur_extra = extras;
while (cur_extra) {
extra_process_t *next = cur_extra->next;
if (reclaim_one_pid(cur_extra->pid, DO_NOTHING)) {
AP_DEBUG_ASSERT(1 == ap_unregister_extra_mpm_process(cur_extra->pid));
}
cur_extra = next;
}
}
#endif /* AP_MPM_WANT_RECLAIM_CHILD_PROCESSES */
#ifdef AP_MPM_WANT_WAIT_OR_TIMEOUT
/* 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;
void ap_wait_or_timeout(apr_exit_why_e *status, int *exitcode, apr_proc_t *ret,
apr_pool_t *p)
{
apr_status_t rv;
++wait_or_timeout_counter;
if (wait_or_timeout_counter == INTERVAL_OF_WRITABLE_PROBES) {
wait_or_timeout_counter = 0;
ap_run_monitor(p);
}
rv = apr_proc_wait_all_procs(ret, exitcode, status, APR_NOWAIT, p);
if (APR_STATUS_IS_EINTR(rv)) {
ret->pid = -1;
return;
}
if (APR_STATUS_IS_CHILD_DONE(rv)) {
return;
}
#ifdef NEED_WAITPID
if ((ret = reap_children(exitcode, status)) > 0) {
return;
}
#endif
apr_sleep(SCOREBOARD_MAINTENANCE_INTERVAL);
ret->pid = -1;
return;
}
#endif /* AP_MPM_WANT_WAIT_OR_TIMEOUT */
#ifdef AP_MPM_WANT_PROCESS_CHILD_STATUS
int ap_process_child_status(apr_proc_t *pid, apr_exit_why_e why, int status)
{
int signum = status;
const char *sigdesc = apr_signal_description_get(signum);
/* Child died... if it died due to a fatal error,
* we should simply bail out. The caller needs to
* check for bad rc from us and exit, running any
* appropriate cleanups.
*
* If the child died due to a resource shortage,
* the parent should limit the rate of forking
*/
if (APR_PROC_CHECK_EXIT(why)) {
if (status == APEXIT_CHILDSICK) {
return status;
}
if (status == APEXIT_CHILDFATAL) {
ap_log_error(APLOG_MARK, APLOG_ALERT,
0, ap_server_conf,
"Child %" APR_PID_T_FMT
" returned a Fatal error... Apache is exiting!",
pid->pid);
return APEXIT_CHILDFATAL;
}
return 0;
}
if (APR_PROC_CHECK_SIGNALED(why)) {
switch (signum) {
case SIGTERM:
case SIGHUP:
case AP_SIG_GRACEFUL:
case SIGKILL:
break;
default:
if (APR_PROC_CHECK_CORE_DUMP(why)) {
ap_log_error(APLOG_MARK, APLOG_NOTICE,
0, ap_server_conf,
"child pid %ld exit signal %s (%d), "
"possible coredump in %s",
(long)pid->pid, sigdesc, signum,
ap_coredump_dir);
}
else {
ap_log_error(APLOG_MARK, APLOG_NOTICE,
0, ap_server_conf,
"child pid %ld exit signal %s (%d)",
(long)pid->pid, sigdesc, signum);
}
}
}
return 0;
}
#endif /* AP_MPM_WANT_PROCESS_CHILD_STATUS */
#if defined(TCP_NODELAY) && !defined(MPE) && !defined(TPF)
void ap_sock_disable_nagle(apr_socket_t *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.
*/
apr_status_t status = apr_socket_opt_set(s, APR_TCP_NODELAY, 1);
if (status != APR_SUCCESS) {
ap_log_error(APLOG_MARK, APLOG_WARNING, status, ap_server_conf,
"apr_socket_opt_set: (TCP_NODELAY)");
}
}
#endif
#ifdef HAVE_GETPWNAM
AP_DECLARE(uid_t) ap_uname2id(const char *name)
{
struct passwd *ent;
if (name[0] == '#')
return (atoi(&name[1]));
if (!(ent = getpwnam(name))) {
ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
"%s: bad user name %s", ap_server_argv0, name);
exit(1);
}
return (ent->pw_uid);
}
#endif
#ifdef HAVE_GETGRNAM
AP_DECLARE(gid_t) ap_gname2id(const char *name)
{
struct group *ent;
if (name[0] == '#')
return (atoi(&name[1]));
if (!(ent = getgrnam(name))) {
ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
"%s: bad group name %s", ap_server_argv0, name);
exit(1);
}
return (ent->gr_gid);
}
#endif
#ifndef HAVE_INITGROUPS
int initgroups(const char *name, gid_t basegid)
{
#if defined(QNX) || defined(MPE) || defined(BEOS) || defined(_OSD_POSIX) || defined(TPF) || defined(__TANDEM) || defined(OS2) || defined(WIN32) || defined(NETWARE)
/* QNX, MPE and BeOS do not appear to support supplementary groups. */
return 0;
#else /* ndef QNX */
gid_t groups[NGROUPS_MAX];
struct group *g;
int index = 0;
setgrent();
groups[index++] = basegid;
while (index < NGROUPS_MAX && ((g = getgrent()) != NULL)) {
if (g->gr_gid != basegid) {
char **names;
for (names = g->gr_mem; *names != NULL; ++names) {
if (!strcmp(*names, name))
groups[index++] = g->gr_gid;
}
}
}
endgrent();
return setgroups(index, groups);
#endif /* def QNX */
}
#endif /* def NEED_INITGROUPS */
#ifdef AP_MPM_USES_POD
AP_DECLARE(apr_status_t) ap_mpm_pod_open(apr_pool_t *p, ap_pod_t **pod)
{
apr_status_t rv;
*pod = apr_palloc(p, sizeof(**pod));
rv = apr_file_pipe_create(&((*pod)->pod_in), &((*pod)->pod_out), p);
if (rv != APR_SUCCESS) {
return rv;
}
apr_file_pipe_timeout_set((*pod)->pod_in, 0);
(*pod)->p = p;
/* close these before exec. */
apr_file_inherit_unset((*pod)->pod_in);
apr_file_inherit_unset((*pod)->pod_out);
return APR_SUCCESS;
}
AP_DECLARE(apr_status_t) ap_mpm_pod_check(ap_pod_t *pod)
{
char c;
apr_size_t len = 1;
apr_status_t rv;
rv = apr_file_read(pod->pod_in, &c, &len);
if ((rv == APR_SUCCESS) && (len == 1)) {
return APR_SUCCESS;
}
if (rv != APR_SUCCESS) {
return rv;
}
return AP_NORESTART;
}
AP_DECLARE(apr_status_t) ap_mpm_pod_close(ap_pod_t *pod)
{
apr_status_t rv;
rv = apr_file_close(pod->pod_out);
if (rv != APR_SUCCESS) {
return rv;
}
rv = apr_file_close(pod->pod_in);
if (rv != APR_SUCCESS) {
return rv;
}
return APR_SUCCESS;
}
static apr_status_t pod_signal_internal(ap_pod_t *pod)
{
apr_status_t rv;
char char_of_death = '!';
apr_size_t one = 1;
rv = apr_file_write(pod->pod_out, &char_of_death, &one);
if (rv != APR_SUCCESS) {
ap_log_error(APLOG_MARK, APLOG_WARNING, rv, ap_server_conf,
"write pipe_of_death");
}
return rv;
}
/* This function connects to the server, then immediately closes the connection.
* This permits the MPM to skip the poll when there is only one listening
* socket, because it provides a alternate way to unblock an accept() when
* the pod is used.
*/
static apr_status_t dummy_connection(ap_pod_t *pod)
{
char *srequest;
apr_status_t rv;
apr_socket_t *sock;
apr_pool_t *p;
apr_size_t len;
/* create a temporary pool for the socket. pconf stays around too long */
rv = apr_pool_create(&p, pod->p);
if (rv != APR_SUCCESS) {
return rv;
}
rv = apr_socket_create(&sock, ap_listeners->bind_addr->family,
SOCK_STREAM, 0, p);
if (rv != APR_SUCCESS) {
ap_log_error(APLOG_MARK, APLOG_WARNING, rv, ap_server_conf,
"get socket to connect to listener");
apr_pool_destroy(p);
return rv;
}
/* on some platforms (e.g., FreeBSD), the kernel won't accept many
* queued connections before it starts blocking local connects...
* we need to keep from blocking too long and instead return an error,
* because the MPM won't want to hold up a graceful restart for a
* long time
*/
rv = apr_socket_timeout_set(sock, apr_time_from_sec(3));
if (rv != APR_SUCCESS) {
ap_log_error(APLOG_MARK, APLOG_WARNING, rv, ap_server_conf,
"set timeout on socket to connect to listener");
apr_socket_close(sock);
apr_pool_destroy(p);
return rv;
}
rv = apr_socket_connect(sock, ap_listeners->bind_addr);
if (rv != APR_SUCCESS) {
int log_level = APLOG_WARNING;
if (APR_STATUS_IS_TIMEUP(rv)) {
/* probably some server processes bailed out already and there
* is nobody around to call accept and clear out the kernel
* connection queue; usually this is not worth logging
*/
log_level = APLOG_DEBUG;
}
ap_log_error(APLOG_MARK, log_level, rv, ap_server_conf,
"connect to listener on %pI", ap_listeners->bind_addr);
}
/* Create the request string. We include a User-Agent so that
* adminstrators can track down the cause of the odd-looking
* requests in their logs.
*/
srequest = apr_pstrcat(p, "OPTIONS * HTTP/1.0\r\nUser-Agent: ",
ap_get_server_banner(),
" (internal dummy connection)\r\n\r\n", NULL);
/* Since some operating systems support buffering of data or entire
* requests in the kernel, we send a simple request, to make sure
* the server pops out of a blocking accept().
*/
/* XXX: This is HTTP specific. We should look at the Protocol for each
* listener, and send the correct type of request to trigger any Accept
* Filters.
*/
len = strlen(srequest);
apr_socket_send(sock, srequest, &len);
apr_socket_close(sock);
apr_pool_destroy(p);
return rv;
}
AP_DECLARE(apr_status_t) ap_mpm_pod_signal(ap_pod_t *pod)
{
apr_status_t rv;
rv = pod_signal_internal(pod);
if (rv != APR_SUCCESS) {
return rv;
}
return dummy_connection(pod);
}
void ap_mpm_pod_killpg(ap_pod_t *pod, int num)
{
int i;
apr_status_t rv = APR_SUCCESS;
/* we don't write anything to the pod here... we assume
* that the would-be reader of the pod has another way to
* see that it is time to die once we wake it up
*
* writing lots of things to the pod at once is very
* problematic... we can fill the kernel pipe buffer and
* be blocked until somebody consumes some bytes or
* we hit a timeout... if we hit a timeout we can't just
* keep trying because maybe we'll never successfully
* write again... but then maybe we'll leave would-be
* readers stranded (a number of them could be tied up for
* a while serving time-consuming requests)
*/
for (i = 0; i < num && rv == APR_SUCCESS; i++) {
rv = dummy_connection(pod);
}
}
#endif /* #ifdef AP_MPM_USES_POD */
/* standard mpm configuration handling */
#ifdef AP_MPM_WANT_SET_PIDFILE
const char *ap_pid_fname = NULL;
const char *ap_mpm_set_pidfile(cmd_parms *cmd, void *dummy,
const char *arg)
{
const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
if (err != NULL) {
return err;
}
if (cmd->server->is_virtual) {
return "PidFile directive not allowed in <VirtualHost>";
}
ap_pid_fname = arg;
return NULL;
}
#endif
#ifdef AP_MPM_WANT_SET_SCOREBOARD
const char * ap_mpm_set_scoreboard(cmd_parms *cmd, void *dummy,
const char *arg)
{
const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
if (err != NULL) {
return err;
}
ap_scoreboard_fname = arg;
return NULL;
}
#endif
#ifdef AP_MPM_WANT_SET_LOCKFILE
const char *ap_lock_fname = NULL;
const char *ap_mpm_set_lockfile(cmd_parms *cmd, void *dummy,
const char *arg)
{
const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
if (err != NULL) {
return err;
}
ap_lock_fname = arg;
return NULL;
}
#endif
#ifdef AP_MPM_WANT_SET_MAX_REQUESTS
int ap_max_requests_per_child = 0;
const char *ap_mpm_set_max_requests(cmd_parms *cmd, void *dummy,
const char *arg)
{
const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
if (err != NULL) {
return err;
}
ap_max_requests_per_child = atoi(arg);
return NULL;
}
#endif
#ifdef AP_MPM_WANT_SET_COREDUMPDIR
char ap_coredump_dir[MAX_STRING_LEN];
int ap_coredumpdir_configured;
const char *ap_mpm_set_coredumpdir(cmd_parms *cmd, void *dummy,
const char *arg)
{
apr_status_t rv;
apr_finfo_t finfo;
const char *fname;
const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
if (err != NULL) {
return err;
}
fname = ap_server_root_relative(cmd->pool, arg);
if (!fname) {
return apr_pstrcat(cmd->pool, "Invalid CoreDumpDirectory path ",
arg, NULL);
}
if ((rv = apr_stat(&finfo, fname, APR_FINFO_TYPE, cmd->pool)) != APR_SUCCESS) {
return apr_pstrcat(cmd->pool, "CoreDumpDirectory ", fname,
" does not exist", NULL);
}
if (finfo.filetype != APR_DIR) {
return apr_pstrcat(cmd->pool, "CoreDumpDirectory ", fname,
" is not a directory", NULL);
}
apr_cpystrn(ap_coredump_dir, fname, sizeof(ap_coredump_dir));
ap_coredumpdir_configured = 1;
return NULL;
}
#endif
#ifdef AP_MPM_WANT_SET_GRACEFUL_SHUTDOWN
int ap_graceful_shutdown_timeout = 0;
const char * ap_mpm_set_graceful_shutdown(cmd_parms *cmd, void *dummy,
const char *arg)
{
const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
if (err != NULL) {
return err;
}
ap_graceful_shutdown_timeout = atoi(arg);
return NULL;
}
#endif
#ifdef AP_MPM_WANT_SET_ACCEPT_LOCK_MECH
apr_lockmech_e ap_accept_lock_mech = APR_LOCK_DEFAULT;
AP_DECLARE(const char *) ap_mpm_set_accept_lock_mech(cmd_parms *cmd,
void *dummy,
const char *arg)
{
apr_status_t rv;
const char *lockfile;
const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
if (err != NULL) {
return err;
}
rv = ap_parse_mutex(arg, cmd->server->process->pool,
&ap_accept_lock_mech, &lockfile);
if ((rv == APR_ENOTIMPL) || (rv == APR_ENOLOCK)) {
return apr_pstrcat(cmd->pool, "Invalid AcceptMutex argument ", arg,
" (", ap_available_mutexes_string, ")", NULL);
} else if (rv == APR_BADARG) {
return apr_pstrcat(cmd->pool, "Invalid AcceptMutex filepath ",
arg, NULL);
}
/* perchild can't use SysV sems because the permissions on the accept
* mutex can't be set to allow all processes to use the mutex and
* at the same time keep all users from being able to dink with the
* mutex
*/
#if defined(PERCHILD_MPM)
if (ap_accept_lock_mech == APR_LOCK_SYSVSEM) {
return apr_pstrcat(cmd->pool, "Invalid AcceptMutex argument ", arg,
" (", ap_available_mutexes_string, ")", NULL);
}
#endif
if (lockfile && !ap_lock_fname)
ap_lock_fname = lockfile;
return NULL;
}
#endif
#ifdef AP_MPM_WANT_SIGNAL_SERVER
static const char *dash_k_arg;
static int send_signal(pid_t pid, int sig)
{
if (kill(pid, sig) < 0) {
ap_log_error(APLOG_MARK, APLOG_STARTUP, errno, NULL,
"sending signal to server");
return 1;
}
return 0;
}
int ap_signal_server(int *exit_status, apr_pool_t *pconf)
{
apr_status_t rv;
pid_t otherpid;
int running = 0;
int have_pid_file = 0;
const char *status;
*exit_status = 0;
rv = ap_read_pid(pconf, ap_pid_fname, &otherpid);
if (rv != APR_SUCCESS) {
if (rv != APR_ENOENT) {
ap_log_error(APLOG_MARK, APLOG_STARTUP, rv, NULL,
"Error retrieving pid file %s", ap_pid_fname);
ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
"Remove it before continuing if it is corrupted.");
*exit_status = 1;
return 1;
}
status = "httpd (no pid file) not running";
}
else {
have_pid_file = 1;
if (kill(otherpid, 0) == 0) {
running = 1;
status = apr_psprintf(pconf,
"httpd (pid %" APR_PID_T_FMT ") already "
"running", otherpid);
}
else {
status = apr_psprintf(pconf,
"httpd (pid %" APR_PID_T_FMT "?) not running",
otherpid);
}
}
if (!strcmp(dash_k_arg, "start")) {
if (running) {
printf("%s\n", status);
return 1;
}
}
if (!strcmp(dash_k_arg, "stop")) {
if (!running) {
printf("%s\n", status);
}
else {
send_signal(otherpid, SIGTERM);
}
return 1;
}
if (!strcmp(dash_k_arg, "restart")) {
if (!running) {
printf("httpd not running, trying to start\n");
}
else {
*exit_status = send_signal(otherpid, SIGHUP);
return 1;
}
}
if (!strcmp(dash_k_arg, "graceful")) {
if (!running) {
printf("httpd not running, trying to start\n");
}
else {
*exit_status = send_signal(otherpid, AP_SIG_GRACEFUL);
return 1;
}
}
if (!strcmp(dash_k_arg, "graceful-stop")) {
#ifdef AP_MPM_WANT_SET_GRACEFUL_SHUTDOWN
if (!running) {
printf("%s\n", status);
}
else {
*exit_status = send_signal(otherpid, AP_SIG_GRACEFUL_STOP);
}
#else
printf("httpd MPM \"" MPM_NAME "\" does not support graceful-stop\n");
#endif
return 1;
}
return 0;
}
void ap_mpm_rewrite_args(process_rec *process)
{
apr_array_header_t *mpm_new_argv;
apr_status_t rv;
apr_getopt_t *opt;
char optbuf[3];
const char *optarg;
int fixed_args;
mpm_new_argv = apr_array_make(process->pool, process->argc,
sizeof(const char **));
*(const char **)apr_array_push(mpm_new_argv) = process->argv[0];
fixed_args = mpm_new_argv->nelts;
apr_getopt_init(&opt, process->pool, process->argc, process->argv);
opt->errfn = NULL;
optbuf[0] = '-';
/* option char returned by apr_getopt() will be stored in optbuf[1] */
optbuf[2] = '\0';
while ((rv = apr_getopt(opt, "k:" AP_SERVER_BASEARGS,
optbuf + 1, &optarg)) == APR_SUCCESS) {
switch(optbuf[1]) {
case 'k':
if (!dash_k_arg) {
if (!strcmp(optarg, "start") || !strcmp(optarg, "stop") ||
!strcmp(optarg, "restart") || !strcmp(optarg, "graceful") ||
!strcmp(optarg, "graceful-stop")) {
dash_k_arg = optarg;
break;
}
}
default:
*(const char **)apr_array_push(mpm_new_argv) =
apr_pstrdup(process->pool, optbuf);
if (optarg) {
*(const char **)apr_array_push(mpm_new_argv) = optarg;
}
}
}
/* back up to capture the bad argument */
if (rv == APR_BADCH || rv == APR_BADARG) {
opt->ind--;
}
while (opt->ind < opt->argc) {
*(const char **)apr_array_push(mpm_new_argv) =
apr_pstrdup(process->pool, opt->argv[opt->ind++]);
}
process->argc = mpm_new_argv->nelts;
process->argv = (const char * const *)mpm_new_argv->elts;
if (dash_k_arg) {
APR_REGISTER_OPTIONAL_FN(ap_signal_server);
}
}
#endif /* AP_MPM_WANT_SIGNAL_SERVER */
#ifdef AP_MPM_WANT_SET_MAX_MEM_FREE
apr_uint32_t ap_max_mem_free = APR_ALLOCATOR_MAX_FREE_UNLIMITED;
const char *ap_mpm_set_max_mem_free(cmd_parms *cmd, void *dummy,
const char *arg)
{
long value;
const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
if (err != NULL) {
return err;
}
value = strtol(arg, NULL, 0);
if (value < 0 || errno == ERANGE)
return apr_pstrcat(cmd->pool, "Invalid MaxMemFree value: ",
arg, NULL);
ap_max_mem_free = (apr_uint32_t)value * 1024;
return NULL;
}
#endif /* AP_MPM_WANT_SET_MAX_MEM_FREE */
#ifdef AP_MPM_WANT_SET_STACKSIZE
apr_size_t ap_thread_stacksize = 0; /* use system default */
const char *ap_mpm_set_thread_stacksize(cmd_parms *cmd, void *dummy,
const char *arg)
{
long value;
const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
if (err != NULL) {
return err;
}
value = strtol(arg, NULL, 0);
if (value < 0 || errno == ERANGE)
return apr_pstrcat(cmd->pool, "Invalid ThreadStackSize value: ",
arg, NULL);
ap_thread_stacksize = (apr_size_t)value;
return NULL;
}
#endif /* AP_MPM_WANT_SET_STACKSIZE */
#ifdef AP_MPM_WANT_FATAL_SIGNAL_HANDLER
static pid_t parent_pid, my_pid;
apr_pool_t *pconf;
#if AP_ENABLE_EXCEPTION_HOOK
static int exception_hook_enabled;
const char *ap_mpm_set_exception_hook(cmd_parms *cmd, void *dummy,
const char *arg)
{
const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
if (err != NULL) {
return err;
}
if (cmd->server->is_virtual) {
return "EnableExceptionHook directive not allowed in <VirtualHost>";
}
if (strcasecmp(arg, "on") == 0) {
exception_hook_enabled = 1;
}
else if (strcasecmp(arg, "off") == 0) {
exception_hook_enabled = 0;
}
else {
return "parameter must be 'on' or 'off'";
}
return NULL;
}
static void run_fatal_exception_hook(int sig)
{
ap_exception_info_t ei = {0};
if (exception_hook_enabled &&
geteuid() != 0 &&
my_pid != parent_pid) {
ei.sig = sig;
ei.pid = my_pid;
ap_run_fatal_exception(&ei);
}
}
#endif /* AP_ENABLE_EXCEPTION_HOOK */
/* handle all varieties of core dumping signals */
static void sig_coredump(int sig)
{
apr_filepath_set(ap_coredump_dir, pconf);
apr_signal(sig, SIG_DFL);
#if AP_ENABLE_EXCEPTION_HOOK
run_fatal_exception_hook(sig);
#endif
/* linuxthreads issue calling getpid() here:
* This comparison won't match if the crashing thread is
* some module's thread that runs in the parent process.
* The fallout, which is limited to linuxthreads:
* The special log message won't be written when such a
* thread in the parent causes the parent to crash.
*/
if (getpid() == parent_pid) {
ap_log_error(APLOG_MARK, APLOG_NOTICE,
0, ap_server_conf,
"seg fault or similar nasty error detected "
"in the parent process");
/* XXX we can probably add some rudimentary cleanup code here,
* like getting rid of the pid file. If any additional bad stuff
* happens, we are protected from recursive errors taking down the
* system since this function is no longer the signal handler GLA
*/
}
kill(getpid(), sig);
/* At this point we've got sig blocked, because we're still inside
* the signal handler. When we leave the signal handler it will
* be unblocked, and we'll take the signal... and coredump or whatever
* is appropriate for this particular Unix. In addition the parent
* will see the real signal we received -- whereas if we called
* abort() here, the parent would only see SIGABRT.
*/
}
apr_status_t ap_fatal_signal_child_setup(server_rec *s)
{
my_pid = getpid();
return APR_SUCCESS;
}
apr_status_t ap_fatal_signal_setup(server_rec *s, apr_pool_t *in_pconf)
{
#ifndef NO_USE_SIGACTION
struct sigaction sa;
sigemptyset(&sa.sa_mask);
#if defined(SA_ONESHOT)
sa.sa_flags = SA_ONESHOT;
#elif defined(SA_RESETHAND)
sa.sa_flags = SA_RESETHAND;
#else
sa.sa_flags = 0;
#endif
sa.sa_handler = sig_coredump;
if (sigaction(SIGSEGV, &sa, NULL) < 0)
ap_log_error(APLOG_MARK, APLOG_WARNING, errno, s, "sigaction(SIGSEGV)");
#ifdef SIGBUS
if (sigaction(SIGBUS, &sa, NULL) < 0)
ap_log_error(APLOG_MARK, APLOG_WARNING, errno, s, "sigaction(SIGBUS)");
#endif
#ifdef SIGABORT
if (sigaction(SIGABORT, &sa, NULL) < 0)
ap_log_error(APLOG_MARK, APLOG_WARNING, errno, s, "sigaction(SIGABORT)");
#endif
#ifdef SIGABRT
if (sigaction(SIGABRT, &sa, NULL) < 0)
ap_log_error(APLOG_MARK, APLOG_WARNING, errno, s, "sigaction(SIGABRT)");
#endif
#ifdef SIGILL
if (sigaction(SIGILL, &sa, NULL) < 0)
ap_log_error(APLOG_MARK, APLOG_WARNING, errno, s, "sigaction(SIGILL)");
#endif
#ifdef SIGFPE
if (sigaction(SIGFPE, &sa, NULL) < 0)
ap_log_error(APLOG_MARK, APLOG_WARNING, errno, s, "sigaction(SIGFPE)");
#endif
#else /* NO_USE_SIGACTION */
apr_signal(SIGSEGV, sig_coredump);
#ifdef SIGBUS
apr_signal(SIGBUS, sig_coredump);
#endif /* SIGBUS */
#ifdef SIGABORT
apr_signal(SIGABORT, sig_coredump);
#endif /* SIGABORT */
#ifdef SIGABRT
apr_signal(SIGABRT, sig_coredump);
#endif /* SIGABRT */
#ifdef SIGILL
apr_signal(SIGILL, sig_coredump);
#endif /* SIGILL */
#ifdef SIGFPE
apr_signal(SIGFPE, sig_coredump);
#endif /* SIGFPE */
#endif /* NO_USE_SIGACTION */
pconf = in_pconf;
parent_pid = my_pid = getpid();
return APR_SUCCESS;
}
#endif /* AP_MPM_WANT_FATAL_SIGNAL_HANDLER */