1
/* Licensed to the Apache Software Foundation (ASF) under one or more
2
* contributor license agreements. See the NOTICE file distributed with
3
* this work for additional information regarding copyright ownership.
4
* The ASF licenses this file to You under the Apache License, Version 2.0
5
* (the "License"); you may not use this file except in compliance with
6
* the License. You may obtain a copy of the License at
8
* http://www.apache.org/licenses/LICENSE-2.0
10
* Unless required by applicable law or agreed to in writing, software
11
* distributed under the License is distributed on an "AS IS" BASIS,
12
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13
* See the License for the specific language governing permissions and
14
* limitations under the License.
17
/* The purpose of this file is to store the code that MOST mpm's will need
18
* this does not mean a function only goes into this file if every MPM needs
19
* it. It means that if a function is needed by more than one MPM, and
20
* future maintenance would be served by making the code common, then the
21
* function belongs here.
23
* This is going in src/main because it is not platform specific, it is
24
* specific to multi-process servers, but NOT to Unix. Which is why it
25
* does not belong in src/os/unix
30
* @brief Multi-Processing Modules functions
32
* @defgroup APACHE_MPM Multi-Processing Modules
37
#ifndef APACHE_MPM_COMMON_H
38
#define APACHE_MPM_COMMON_H
40
#include "ap_config.h"
42
#if APR_HAVE_NETINET_TCP_H
43
#include <netinet/tcp.h> /* for TCP_NODELAY */
52
/* The maximum length of the queue of pending connections, as defined
53
* by listen(2). Under some systems, it should be increased if you
54
* are experiencing a heavy TCP SYN flood attack.
56
* It defaults to 511 instead of 512 because some systems store it
57
* as an 8-bit datatype; 512 truncated to 8-bits is 0, while 511 is
60
#ifndef DEFAULT_LISTENBACKLOG
61
#define DEFAULT_LISTENBACKLOG 511
64
/* Signal used to gracefully restart */
65
#define AP_SIG_GRACEFUL SIGUSR1
67
/* Signal used to gracefully restart (without SIG prefix) */
68
#define AP_SIG_GRACEFUL_SHORT USR1
70
/* Signal used to gracefully restart (as a quoted string) */
71
#define AP_SIG_GRACEFUL_STRING "SIGUSR1"
73
/* Signal used to gracefully stop */
74
#define AP_SIG_GRACEFUL_STOP SIGWINCH
76
/* Signal used to gracefully stop (without SIG prefix) */
77
#define AP_SIG_GRACEFUL_STOP_SHORT WINCH
79
/* Signal used to gracefully stop (as a quoted string) */
80
#define AP_SIG_GRACEFUL_STOP_STRING "SIGWINCH"
83
* Make sure all child processes that have been spawned by the parent process
84
* have died. This includes process registered as "other_children".
85
* @warning This is only defined if the MPM defines
86
* AP_MPM_WANT_RECLAIM_CHILD_PROCESSES
87
* @param terminate Either 1 or 0. If 1, send the child processes SIGTERM
88
* each time through the loop. If 0, give the process time to die
89
* on its own before signalling it.
90
* @tip This function requires that some macros are defined by the MPM: <pre>
91
* MPM_CHILD_PID -- Get the pid from the specified spot in the scoreboard
92
* MPM_NOTE_CHILD_KILLED -- Note the child died in the scoreboard
94
* @tip The MPM child processes which are reclaimed are those listed
95
* in the scoreboard as well as those currently registered via
96
* ap_register_extra_mpm_process().
98
#ifdef AP_MPM_WANT_RECLAIM_CHILD_PROCESSES
99
void ap_reclaim_child_processes(int terminate);
103
* Catch any child processes that have been spawned by the parent process
104
* which have exited. This includes processes registered as "other_children".
105
* @warning This is only defined if the MPM defines
106
* AP_MPM_WANT_RECLAIM_CHILD_PROCESSES
107
* @tip This function requires that some macros are defined by the MPM: <pre>
108
* MPM_CHILD_PID -- Get the pid from the specified spot in the scoreboard
109
* MPM_NOTE_CHILD_KILLED -- Note the child died in the scoreboard
111
* @tip The MPM child processes which are relieved are those listed
112
* in the scoreboard as well as those currently registered via
113
* ap_register_extra_mpm_process().
115
#ifdef AP_MPM_WANT_RECLAIM_CHILD_PROCESSES
116
void ap_relieve_child_processes(void);
120
* Tell ap_reclaim_child_processes() and ap_relieve_child_processes() about
121
* an MPM child process which has no entry in the scoreboard.
122
* @warning This is only defined if the MPM defines
123
* AP_MPM_WANT_RECLAIM_CHILD_PROCESSES
124
* @param pid The process id of an MPM child process which should be
125
* reclaimed when ap_reclaim_child_processes() is called.
126
* @tip If an extra MPM child process terminates prior to calling
127
* ap_reclaim_child_processes(), remove it from the list of such processes
128
* by calling ap_unregister_extra_mpm_process().
130
#ifdef AP_MPM_WANT_RECLAIM_CHILD_PROCESSES
131
void ap_register_extra_mpm_process(pid_t pid);
135
* Unregister an MPM child process which was previously registered by a
136
* call to ap_register_extra_mpm_process().
137
* @warning This is only defined if the MPM defines
138
* AP_MPM_WANT_RECLAIM_CHILD_PROCESSES
139
* @param pid The process id of an MPM child process which no longer needs to
141
* @return 1 if the process was found and removed, 0 otherwise
143
#ifdef AP_MPM_WANT_RECLAIM_CHILD_PROCESSES
144
int ap_unregister_extra_mpm_process(pid_t pid);
148
* Determine if any child process has died. If no child process died, then
149
* this process sleeps for the amount of time specified by the MPM defined
150
* macro SCOREBOARD_MAINTENANCE_INTERVAL.
151
* @param status The return code if a process has died
152
* @param ret The process id of the process that died
153
* @param p The pool to allocate out of
155
#ifdef AP_MPM_WANT_WAIT_OR_TIMEOUT
156
void ap_wait_or_timeout(apr_exit_why_e *status, int *exitcode, apr_proc_t *ret,
161
* Log why a child died to the error log, if the child died without the
162
* parent signalling it.
163
* @param pid The child that has died
164
* @param status The status returned from ap_wait_or_timeout
165
* @return 0 on success, APEXIT_CHILDFATAL if MPM should terminate
167
#ifdef AP_MPM_WANT_PROCESS_CHILD_STATUS
168
int ap_process_child_status(apr_proc_t *pid, apr_exit_why_e why, int status);
171
#if defined(TCP_NODELAY) && !defined(MPE) && !defined(TPF)
173
* Turn off the nagle algorithm for the specified socket. The nagle algorithm
174
* says that we should delay sending partial packets in the hopes of getting
175
* more data. There are bad interactions between persistent connections and
176
* Nagle's algorithm that have severe performance penalties.
177
* @param s The socket to disable nagle for.
179
void ap_sock_disable_nagle(apr_socket_t *s);
181
#define ap_sock_disable_nagle(s) /* NOOP */
186
* Convert a username to a numeric ID
187
* @param name The name to convert
188
* @return The user id corresponding to a name
189
* @deffunc uid_t ap_uname2id(const char *name)
191
AP_DECLARE(uid_t) ap_uname2id(const char *name);
196
* Convert a group name to a numeric ID
197
* @param name The name to convert
198
* @return The group id corresponding to a name
199
* @deffunc gid_t ap_gname2id(const char *name)
201
AP_DECLARE(gid_t) ap_gname2id(const char *name);
204
#define AP_MPM_HARD_LIMITS_FILE APACHE_MPM_DIR "/mpm_default.h"
206
#ifdef AP_MPM_USES_POD
208
typedef struct ap_pod_t ap_pod_t;
217
* Open the pipe-of-death. The pipe of death is used to tell all child
218
* processes that it is time to die gracefully.
219
* @param p The pool to use for allocating the pipe
221
AP_DECLARE(apr_status_t) ap_mpm_pod_open(apr_pool_t *p, ap_pod_t **pod);
224
* Check the pipe to determine if the process has been signalled to die.
226
AP_DECLARE(apr_status_t) ap_mpm_pod_check(ap_pod_t *pod);
229
* Close the pipe-of-death
231
AP_DECLARE(apr_status_t) ap_mpm_pod_close(ap_pod_t *pod);
234
* Write data to the pipe-of-death, signalling that one child process
236
* @param p The pool to use when allocating any required structures.
238
AP_DECLARE(apr_status_t) ap_mpm_pod_signal(ap_pod_t *pod);
241
* Write data to the pipe-of-death, signalling that all child process
243
* @param p The pool to use when allocating any required structures.
244
* @param num The number of child processes to kill
246
AP_DECLARE(void) ap_mpm_pod_killpg(ap_pod_t *pod, int num);
250
* These data members are common to all mpms. Each new mpm
251
* should either use the appropriate ap_mpm_set_* function
252
* in their command table or create their own for custom or
253
* OS specific needs. These should work for most.
257
* The maximum number of requests each child thread or
258
* process handles before dying off
260
#ifdef AP_MPM_WANT_SET_MAX_REQUESTS
261
extern int ap_max_requests_per_child;
262
const char *ap_mpm_set_max_requests(cmd_parms *cmd, void *dummy,
267
* The filename used to store the process id.
269
#ifdef AP_MPM_WANT_SET_PIDFILE
270
extern const char *ap_pid_fname;
271
const char *ap_mpm_set_pidfile(cmd_parms *cmd, void *dummy,
276
* The name of lockfile used when Apache needs to lock the accept() call.
278
#ifdef AP_MPM_WANT_SET_LOCKFILE
279
extern const char *ap_lock_fname;
280
const char *ap_mpm_set_lockfile(cmd_parms *cmd, void *dummy,
285
* The system mutex implementation to use for the accept mutex.
287
#ifdef AP_MPM_WANT_SET_ACCEPT_LOCK_MECH
288
extern apr_lockmech_e ap_accept_lock_mech;
289
extern const char ap_valid_accept_mutex_string[];
290
const char *ap_mpm_set_accept_lock_mech(cmd_parms *cmd, void *dummy,
295
* Set the scorboard file.
297
#ifdef AP_MPM_WANT_SET_SCOREBOARD
298
const char *ap_mpm_set_scoreboard(cmd_parms *cmd, void *dummy,
303
* The directory that the server changes directory to dump core.
305
#ifdef AP_MPM_WANT_SET_COREDUMPDIR
306
extern char ap_coredump_dir[MAX_STRING_LEN];
307
extern int ap_coredumpdir_configured;
308
const char *ap_mpm_set_coredumpdir(cmd_parms *cmd, void *dummy,
313
* Set the timeout period for a graceful shutdown.
315
#ifdef AP_MPM_WANT_SET_GRACEFUL_SHUTDOWN
316
extern int ap_graceful_shutdown_timeout;
317
const char *ap_mpm_set_graceful_shutdown(cmd_parms *cmd, void *dummy,
319
#define AP_GRACEFUL_SHUTDOWN_TIMEOUT_COMMAND \
320
AP_INIT_TAKE1("GracefulShutdownTimeout", ap_mpm_set_graceful_shutdown, NULL, \
321
RSRC_CONF, "Maximum time in seconds to wait for child " \
322
"processes to complete transactions during shutdown")
326
#ifdef AP_MPM_WANT_SIGNAL_SERVER
327
int ap_signal_server(int *, apr_pool_t *);
328
void ap_mpm_rewrite_args(process_rec *);
331
#ifdef AP_MPM_WANT_SET_MAX_MEM_FREE
332
extern apr_uint32_t ap_max_mem_free;
333
extern const char *ap_mpm_set_max_mem_free(cmd_parms *cmd, void *dummy,
337
#ifdef AP_MPM_WANT_SET_STACKSIZE
338
extern apr_size_t ap_thread_stacksize;
339
extern const char *ap_mpm_set_thread_stacksize(cmd_parms *cmd, void *dummy,
343
#ifdef AP_MPM_WANT_FATAL_SIGNAL_HANDLER
344
extern apr_status_t ap_fatal_signal_setup(server_rec *s, apr_pool_t *pconf);
345
extern apr_status_t ap_fatal_signal_child_setup(server_rec *s);
348
#if AP_ENABLE_EXCEPTION_HOOK
349
extern const char *ap_mpm_set_exception_hook(cmd_parms *cmd, void *dummy,
353
AP_DECLARE_HOOK(int,monitor,(apr_pool_t *p))
359
#endif /* !APACHE_MPM_COMMON_H */
added
removed
include/mpm_common.h
