httpd/server/util_mutex.c

	util_mutex.c revision d88a642829b2aa45e810f5bcc31be8e901b0aa3b
967e5f3c25249c779575864692935627004d3f9eChristian Maeder/* Licensed to the Apache Software Foundation (ASF) under one or more
967e5f3c25249c779575864692935627004d3f9eChristian Maeder * contributor license agreements.  See the NOTICE file distributed with
967e5f3c25249c779575864692935627004d3f9eChristian Maeder * this work for additional information regarding copyright ownership.
75a6279dbae159d018ef812185416cf6df386c10Till Mossakowski * The ASF licenses this file to You under the Apache License, Version 2.0
967e5f3c25249c779575864692935627004d3f9eChristian Maeder * (the "License"); you may not use this file except in compliance with
967e5f3c25249c779575864692935627004d3f9eChristian Maeder * the License.  You may obtain a copy of the License at
967e5f3c25249c779575864692935627004d3f9eChristian Maeder *
89054b2b95a3f92e78324dc852f3d34704e2ca49Christian Maeder *     http://www.apache.org/licenses/LICENSE-2.0
967e5f3c25249c779575864692935627004d3f9eChristian Maeder *
967e5f3c25249c779575864692935627004d3f9eChristian Maeder * Unless required by applicable law or agreed to in writing, software
967e5f3c25249c779575864692935627004d3f9eChristian Maeder * distributed under the License is distributed on an "AS IS" BASIS,
967e5f3c25249c779575864692935627004d3f9eChristian Maeder * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
967e5f3c25249c779575864692935627004d3f9eChristian Maeder * See the License for the specific language governing permissions and
967e5f3c25249c779575864692935627004d3f9eChristian Maeder * limitations under the License.
967e5f3c25249c779575864692935627004d3f9eChristian Maeder */
fd896e2068ad7e50aed66ac18c3720ea7ff2619fChristian Maeder
7221c71b38c871ce66eee4537cb681d468308dfbChristian Maeder/*
34c05dd06c937d85e7f552e4ff0d36ca0393daeaChristian Maeder * util_mutex.c: Useful functions for determining allowable
7221c71b38c871ce66eee4537cb681d468308dfbChristian Maeder *               mutexes and mutex settings
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder */
967e5f3c25249c779575864692935627004d3f9eChristian Maeder
fd896e2068ad7e50aed66ac18c3720ea7ff2619fChristian Maeder
fd896e2068ad7e50aed66ac18c3720ea7ff2619fChristian Maeder#include "apr.h"
997c56f3bc74a703043010978e5013fdb074d659Christian Maeder#include "apr_hash.h"
967e5f3c25249c779575864692935627004d3f9eChristian Maeder#include "apr_strings.h"
9744c7d9fa61d255d5e73beec7edc3499522e9e2Till Mossakowski#include "apr_lib.h"
9744c7d9fa61d255d5e73beec7edc3499522e9e2Till Mossakowski
fd896e2068ad7e50aed66ac18c3720ea7ff2619fChristian Maeder#define APR_WANT_STRFUNC
89054b2b95a3f92e78324dc852f3d34704e2ca49Christian Maeder#include "apr_want.h"
fd896e2068ad7e50aed66ac18c3720ea7ff2619fChristian Maeder
dea4c92f0c061d589c542d0640a18dab36dfbb46Christian Maeder#include "ap_config.h"
fd896e2068ad7e50aed66ac18c3720ea7ff2619fChristian Maeder#include "httpd.h"
dea4c92f0c061d589c542d0640a18dab36dfbb46Christian Maeder#include "http_main.h"
fd896e2068ad7e50aed66ac18c3720ea7ff2619fChristian Maeder#include "http_config.h"
dea4c92f0c061d589c542d0640a18dab36dfbb46Christian Maeder#include "http_log.h"
dea4c92f0c061d589c542d0640a18dab36dfbb46Christian Maeder#include "util_mutex.h"
dea4c92f0c061d589c542d0640a18dab36dfbb46Christian Maeder#if AP_NEED_SET_MUTEX_PERMS
dea4c92f0c061d589c542d0640a18dab36dfbb46Christian Maeder#include "unixd.h"
dea4c92f0c061d589c542d0640a18dab36dfbb46Christian Maeder#endif
dea4c92f0c061d589c542d0640a18dab36dfbb46Christian Maeder#ifdef HAVE_UNISTD_H
967e5f3c25249c779575864692935627004d3f9eChristian Maeder#include <unistd.h> /* getpid() */
dea4c92f0c061d589c542d0640a18dab36dfbb46Christian Maeder#endif
dea4c92f0c061d589c542d0640a18dab36dfbb46Christian Maeder
dea4c92f0c061d589c542d0640a18dab36dfbb46Christian MaederAP_DECLARE(apr_status_t) ap_parse_mutex(const char *arg, apr_pool_t *pool,
dea4c92f0c061d589c542d0640a18dab36dfbb46Christian Maeder                                        apr_lockmech_e *mutexmech,
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder                                        const char **mutexfile)
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder{
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    /* Split arg into meth and file */
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    char *meth = apr_pstrdup(pool, arg);
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    char *file = strchr(meth, ':');
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    if (file) {
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder        *(file++) = '\0';
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder        if (!*file) {
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder            file = NULL;
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder        }
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    }
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    /* APR determines temporary filename unless overridden below,
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder     * we presume file indicates an mutexfile is a file path
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder     * unless the method sets mutexfile=file and NULLs file
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder     */
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    *mutexfile = NULL;
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    if (!strcasecmp(meth, "none") || !strcasecmp(meth, "no")) {
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder        return APR_ENOLOCK;
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    }
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder
239090e32b9079422ea1ce61197557e5b816f455Christian Maeder    /* NOTE: previously, 'yes' implied 'sem' */
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    if (!strcasecmp(meth, "default") || !strcasecmp(meth, "yes")) {
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder        *mutexmech = APR_LOCK_DEFAULT;
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    }
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder#if APR_HAS_FCNTL_SERIALIZE
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    else if (!strcasecmp(meth, "fcntl") || !strcasecmp(meth, "file")) {
7a879b08ae0ca30006f9be887a73212b07f10204Christian Maeder        *mutexmech = APR_LOCK_FCNTL;
7a879b08ae0ca30006f9be887a73212b07f10204Christian Maeder    }
7a879b08ae0ca30006f9be887a73212b07f10204Christian Maeder#endif
7a879b08ae0ca30006f9be887a73212b07f10204Christian Maeder#if APR_HAS_FLOCK_SERIALIZE
7a879b08ae0ca30006f9be887a73212b07f10204Christian Maeder    else if (!strcasecmp(meth, "flock") || !strcasecmp(meth, "file")) {
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder        *mutexmech = APR_LOCK_FLOCK;
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    }
7a879b08ae0ca30006f9be887a73212b07f10204Christian Maeder#endif
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder#if APR_HAS_POSIXSEM_SERIALIZE
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    else if (!strcasecmp(meth, "posixsem") || !strcasecmp(meth, "sem")) {
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder        *mutexmech = APR_LOCK_POSIXSEM;
09eef8548cd62d787cf3a6535f9eae10592eec89Christian Maeder        /* Posix/SysV semaphores aren't file based, use the literal name
7a879b08ae0ca30006f9be887a73212b07f10204Christian Maeder         * if provided and fall back on APR's default if not.  Today, APR
7a879b08ae0ca30006f9be887a73212b07f10204Christian Maeder         * will ignore it, but once supported it has an absurdly short limit.
7a879b08ae0ca30006f9be887a73212b07f10204Christian Maeder         */
7a879b08ae0ca30006f9be887a73212b07f10204Christian Maeder        if (file) {
7a879b08ae0ca30006f9be887a73212b07f10204Christian Maeder            *mutexfile = apr_pstrdup(pool, file);
7a879b08ae0ca30006f9be887a73212b07f10204Christian Maeder
7a879b08ae0ca30006f9be887a73212b07f10204Christian Maeder            file = NULL;
7a879b08ae0ca30006f9be887a73212b07f10204Christian Maeder        }
34c05dd06c937d85e7f552e4ff0d36ca0393daeaChristian Maeder    }
34c05dd06c937d85e7f552e4ff0d36ca0393daeaChristian Maeder#endif
7a879b08ae0ca30006f9be887a73212b07f10204Christian Maeder#if APR_HAS_SYSVSEM_SERIALIZE
7a879b08ae0ca30006f9be887a73212b07f10204Christian Maeder    else if (!strcasecmp(meth, "sysvsem") || !strcasecmp(meth, "sem")) {
7a879b08ae0ca30006f9be887a73212b07f10204Christian Maeder        *mutexmech = APR_LOCK_SYSVSEM;
7a879b08ae0ca30006f9be887a73212b07f10204Christian Maeder    }
09eef8548cd62d787cf3a6535f9eae10592eec89Christian Maeder#endif
09eef8548cd62d787cf3a6535f9eae10592eec89Christian Maeder#if APR_HAS_PROC_PTHREAD_SERIALIZE
09eef8548cd62d787cf3a6535f9eae10592eec89Christian Maeder    else if (!strcasecmp(meth, "pthread")) {
adee28c3eb7bb0b9bb045d26ee6d35e19cf39053Christian Maeder        *mutexmech = APR_LOCK_PROC_PTHREAD;
adee28c3eb7bb0b9bb045d26ee6d35e19cf39053Christian Maeder    }
adee28c3eb7bb0b9bb045d26ee6d35e19cf39053Christian Maeder#endif
adee28c3eb7bb0b9bb045d26ee6d35e19cf39053Christian Maeder    else {
89054b2b95a3f92e78324dc852f3d34704e2ca49Christian Maeder        return APR_ENOTIMPL;
adee28c3eb7bb0b9bb045d26ee6d35e19cf39053Christian Maeder    }
adee28c3eb7bb0b9bb045d26ee6d35e19cf39053Christian Maeder
adee28c3eb7bb0b9bb045d26ee6d35e19cf39053Christian Maeder    /* Unless the method above assumed responsibility for setting up
adee28c3eb7bb0b9bb045d26ee6d35e19cf39053Christian Maeder     * mutexfile and NULLing out file, presume it is a file we
adee28c3eb7bb0b9bb045d26ee6d35e19cf39053Christian Maeder     * are looking to use
967e5f3c25249c779575864692935627004d3f9eChristian Maeder     */
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    if (file) {
967e5f3c25249c779575864692935627004d3f9eChristian Maeder        *mutexfile = ap_server_root_relative(pool, file);
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder        if (!*mutexfile) {
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder            return APR_BADARG;
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder        }
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder    }
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder    return APR_SUCCESS;
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder}
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maedertypedef struct {
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder    apr_int32_t options;
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder    int set;
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder    int none;
967e5f3c25249c779575864692935627004d3f9eChristian Maeder    int omit_pid;
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder    apr_lockmech_e mech;
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder    const char *dir;
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder} mutex_cfg_t;
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder/* hash is created the first time a module calls ap_mutex_register(),
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder * rather than attempting to be the REALLY_REALLY_FIRST pre-config
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder * hook; it is cleaned up when the associated pool goes away; assume
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder * pconf is the pool passed to ap_mutex_register()
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder */
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maederstatic apr_hash_t *mxcfg_by_type;
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maederstatic apr_status_t cleanup_mx_hash(void *dummy)
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder{
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder    mxcfg_by_type = NULL;
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder    return APR_SUCCESS;
bfa9e03532243ceb487f0384d0f6a447f1ce7670Till Mossakowski}
7221c71b38c871ce66eee4537cb681d468308dfbChristian Maeder
7221c71b38c871ce66eee4537cb681d468308dfbChristian Maederstatic void mx_hash_init(apr_pool_t *p)
7221c71b38c871ce66eee4537cb681d468308dfbChristian Maeder{
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder    mutex_cfg_t *def;
7221c71b38c871ce66eee4537cb681d468308dfbChristian Maeder
7221c71b38c871ce66eee4537cb681d468308dfbChristian Maeder    if (mxcfg_by_type) {
7221c71b38c871ce66eee4537cb681d468308dfbChristian Maeder        return;
7221c71b38c871ce66eee4537cb681d468308dfbChristian Maeder    }
bfa9e03532243ceb487f0384d0f6a447f1ce7670Till Mossakowski
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    mxcfg_by_type = apr_hash_make(p);
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    apr_pool_cleanup_register(p, NULL, cleanup_mx_hash, apr_pool_cleanup_null);
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    /* initialize default mutex configuration */
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    def = apr_pcalloc(p, sizeof *def);
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    def->mech = APR_LOCK_DEFAULT;
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder#ifdef DEFAULT_REL_RUNTIMEDIR
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    def->dir = DEFAULT_REL_RUNTIMEDIR;
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder#else
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    def->dir = "logs";
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder#endif
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    apr_hash_set(mxcfg_by_type, "default", APR_HASH_KEY_STRING, def);
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder}
dea4c92f0c061d589c542d0640a18dab36dfbb46Christian Maeder
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian MaederAP_DECLARE_NONSTD(const char *)ap_set_mutex(cmd_parms *cmd, void *dummy,
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder                                            const char *arg)
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder{
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    apr_pool_t *p = cmd->pool;
7a879b08ae0ca30006f9be887a73212b07f10204Christian Maeder    const char **elt;
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    const char *mechdir;
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    int no_mutex = 0, omit_pid = 0;
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    apr_array_header_t *type_list;
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    apr_lockmech_e mech;
dea4c92f0c061d589c542d0640a18dab36dfbb46Christian Maeder    apr_status_t rv;
dea4c92f0c061d589c542d0640a18dab36dfbb46Christian Maeder    const char *mutexdir;
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    mutex_cfg_t *mxcfg;
7a879b08ae0ca30006f9be887a73212b07f10204Christian Maeder    const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    if (err != NULL) {
7a879b08ae0ca30006f9be887a73212b07f10204Christian Maeder        return err;
0a8ea95bcf0e3f84fed0b725c049ec2a956a4a28Christian Maeder    }
967e5f3c25249c779575864692935627004d3f9eChristian Maeder
967e5f3c25249c779575864692935627004d3f9eChristian Maeder    mechdir = ap_getword_conf(cmd->pool, &arg);
967e5f3c25249c779575864692935627004d3f9eChristian Maeder    if (*mechdir == '\0') {
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder        return "Mutex requires at least a mechanism argument ("
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder               AP_ALL_AVAILABLE_MUTEXES_STRING ")";
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder    }
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder    rv = ap_parse_mutex(mechdir, p, &mech, &mutexdir);
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder    if (rv == APR_ENOTIMPL) {
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder        return apr_pstrcat(p, "Invalid Mutex argument ", mechdir,
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder                           " (" AP_ALL_AVAILABLE_MUTEXES_STRING ")", NULL);
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder    }
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder    else if (rv == APR_BADARG
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder             || (mutexdir && !ap_is_directory(p, mutexdir))) {
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder        return apr_pstrcat(p, "Invalid Mutex directory in argument ",
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder                           mechdir, NULL);
967e5f3c25249c779575864692935627004d3f9eChristian Maeder    }
967e5f3c25249c779575864692935627004d3f9eChristian Maeder    else if (rv == APR_ENOLOCK) { /* "none" */
7221c71b38c871ce66eee4537cb681d468308dfbChristian Maeder        no_mutex = 1;
09eef8548cd62d787cf3a6535f9eae10592eec89Christian Maeder    }
09eef8548cd62d787cf3a6535f9eae10592eec89Christian Maeder
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder    /* "OmitPID" can appear at the end of the list, so build a list of
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder     * mutex type names while looking for "OmitPID" (anywhere) or the end
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder     */
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder    type_list = apr_array_make(cmd->pool, 4, sizeof(char *));
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder    while (*arg) {
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder        char *s = ap_getword_conf(cmd->pool, &arg);
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder        if (!strcasecmp(s, "omitpid")) {
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder            omit_pid = 1;
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder        }
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder        else {
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder            char **new_type = (char **)apr_array_push(type_list);
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder            *new_type = s;
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder        }
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder    }
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder    if (apr_is_empty_array(type_list)) { /* no mutex type?  assume "default" */
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder        char **new_type = (char **)apr_array_push(type_list);
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder        *new_type = "default";
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder    }
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder    while ((elt = (const char **)apr_array_pop(type_list)) != NULL) {
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder        const char *type = *elt;
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder        mxcfg = apr_hash_get(mxcfg_by_type, type, APR_HASH_KEY_STRING);
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder        if (!mxcfg) {
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder            return apr_psprintf(p, "Mutex type %s is not valid", type);
7221c71b38c871ce66eee4537cb681d468308dfbChristian Maeder        }
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder        mxcfg->none = 0; /* in case that was the default */
967e5f3c25249c779575864692935627004d3f9eChristian Maeder        mxcfg->omit_pid = omit_pid;
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder        mxcfg->set = 1;
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder        if (no_mutex) {
83814002b4922114cbe7e9ba728472a0bf44aac5Christian Maeder            if (!(mxcfg->options & AP_MUTEX_ALLOW_NONE)) {
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder                return apr_psprintf(p,
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder                                    "None is not allowed for mutex type %s",
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder                                    type);
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder            }
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder            mxcfg->none = 1;
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder        }
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder        else {
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder            mxcfg->mech = mech;
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder            if (mutexdir) { /* retain mutex default if not configured */
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder                mxcfg->dir = mutexdir;
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder            }
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder        }
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder    }
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder
dedabc954aa15f6ad0764472a9434dc6dafe3db2Christian Maeder    return NULL;
}

AP_DECLARE(apr_status_t) ap_mutex_register(apr_pool_t *pconf,
                                           const char *type,
                                           const char *default_dir,
                                           apr_lockmech_e default_mech,
                                           apr_int32_t options)
{
    mutex_cfg_t *mxcfg = apr_pcalloc(pconf, sizeof *mxcfg);

    if ((options & ~(AP_MUTEX_ALLOW_NONE | AP_MUTEX_DEFAULT_NONE))) {
        return APR_EINVAL;
    }

    mx_hash_init(pconf);

    mxcfg->options = options;
    if (options & AP_MUTEX_DEFAULT_NONE) {
        mxcfg->none = 1;
    }
    mxcfg->dir = default_dir; /* usually NULL */
    mxcfg->mech = default_mech; /* usually APR_LOCK_DEFAULT */
    apr_hash_set(mxcfg_by_type, type, APR_HASH_KEY_STRING, mxcfg);

    return APR_SUCCESS;
}

static int mutex_needs_file(apr_lockmech_e mech)
{
    if (mech != APR_LOCK_FLOCK
        && mech != APR_LOCK_FCNTL
#if APR_USE_FLOCK_SERIALIZE || APR_USE_FCNTL_SERIALIZE
        && mech != APR_LOCK_DEFAULT
#endif
        ) {
        return 0;
    }
    return 1;
}

static const char *get_mutex_filename(apr_pool_t *p, mutex_cfg_t *mxcfg,
                                      const char *type,
                                      const char *instance_id)
{
    const char *pid_suffix = "";

    if (!mutex_needs_file(mxcfg->mech)) {
        return NULL;
    }

#if HAVE_UNISTD_H
    if (!mxcfg->omit_pid) {
        pid_suffix = apr_psprintf(p, ".%" APR_PID_T_FMT, getpid());
    }
#endif

    return ap_server_root_relative(p,
                                   apr_pstrcat(p,
                                               mxcfg->dir,
                                               "/",
                                               type,
                                               instance_id ? "-" : "",
                                               instance_id ? instance_id : "",
                                               pid_suffix,
                                               NULL));
}

static mutex_cfg_t *mxcfg_lookup(apr_pool_t *p, const char *type)
{
    mutex_cfg_t *defcfg, *mxcfg, *newcfg;

    defcfg = apr_hash_get(mxcfg_by_type, "default", APR_HASH_KEY_STRING);

    /* MUST exist in table, or wasn't registered */
    mxcfg = apr_hash_get(mxcfg_by_type, type, APR_HASH_KEY_STRING);
    if (!mxcfg) {
        return NULL;
    }

    /* order of precedence:
     * 1. Mutex directive for this mutex
     * 2. Mutex directive for "default"
     * 3. Defaults for this mutex from ap_mutex_register()
     * 4. Global defaults
     */

    if (mxcfg->set) {
        newcfg = mxcfg;
    }
    else if (defcfg->set) {
        newcfg = defcfg;
    }
    else if (mxcfg->none || mxcfg->mech != APR_LOCK_DEFAULT) {
        newcfg = mxcfg;
    }
    else {
        newcfg = defcfg;
    }

    if (!newcfg->none && mutex_needs_file(newcfg->mech) && !newcfg->dir) {
        /* a file-based mutex mechanism was configured, but
         * without a mutex file directory; go back through
         * the chain to find the directory, store in new
         * mutex cfg structure
         */
        newcfg = apr_pmemdup(p, newcfg, sizeof *newcfg);

        /* !true if dir not already set: mxcfg->set && defcfg->dir */
        if (defcfg->set && defcfg->dir) {
            newcfg->dir = defcfg->dir;
        }
        else if (mxcfg->dir) {
            newcfg->dir = mxcfg->dir;
        }
        else {
            newcfg->dir = defcfg->dir;
        }
    }

    return newcfg;
}

static void log_bad_create_options(server_rec *s, const char *type)
{
    ap_log_error(APLOG_MARK, APLOG_EMERG, 0, s,
                 "Invalid options were specified when creating the %s mutex",
                 type);
}

static void log_unknown_type(server_rec *s, const char *type)
{
    ap_log_error(APLOG_MARK, APLOG_EMERG, 0, s,
                 "Can't create mutex of unknown type %s", type);
}

static void log_create_failure(apr_status_t rv, server_rec *s, const char *type,
                               const char *fname)
{
    ap_log_error(APLOG_MARK, APLOG_EMERG, rv, s,
                 "Couldn't create the %s mutex %s%s%s", type,
                 fname ? "(file " : "",
                 fname ? fname : "",
                 fname ? ")" : "");
}

static void log_perms_failure(apr_status_t rv, server_rec *s, const char *type)
{
    ap_log_error(APLOG_MARK, APLOG_EMERG, rv, s,
                 "Couldn't set permissions on the %s mutex; "
                 "check User and Group directives",
                 type);
}

AP_DECLARE(apr_status_t) ap_global_mutex_create(apr_global_mutex_t **mutex,
                                                const char *type,
                                                const char *instance_id,
                                                server_rec *s, apr_pool_t *p,
                                                apr_int32_t options)
{
    apr_status_t rv;
    const char *fname;
    mutex_cfg_t *mxcfg = mxcfg_lookup(p, type);

    if (options) {
        log_bad_create_options(s, type);
        return APR_EINVAL;
    }

    if (!mxcfg) {
        log_unknown_type(s, type);
        return APR_EINVAL;
    }

    if (mxcfg->none) {
        *mutex = NULL;
        return APR_SUCCESS;
    }

    fname = get_mutex_filename(p, mxcfg, type, instance_id);

    rv = apr_global_mutex_create(mutex, fname, mxcfg->mech, p);
    if (rv != APR_SUCCESS) {
        log_create_failure(rv, s, type, fname);
        return rv;
    }

#ifdef AP_NEED_SET_MUTEX_PERMS
    rv = ap_unixd_set_global_mutex_perms(*mutex);
    if (rv != APR_SUCCESS) {
        log_perms_failure(rv, s, type);
        return rv;
    }
#endif

    return APR_SUCCESS;
}

AP_DECLARE(apr_status_t) ap_proc_mutex_create(apr_proc_mutex_t **mutex,
                                              const char *type,
                                              const char *instance_id,
                                              server_rec *s, apr_pool_t *p,
                                              apr_int32_t options)
{
    apr_status_t rv;
    const char *fname;
    mutex_cfg_t *mxcfg = mxcfg_lookup(p, type);

    if (options) {
        log_bad_create_options(s, type);
        return APR_EINVAL;
    }

    if (!mxcfg) {
        log_unknown_type(s, type);
        return APR_EINVAL;
    }

    if (mxcfg->none) {
        *mutex = NULL;
        return APR_SUCCESS;
    }

    fname = get_mutex_filename(p, mxcfg, type, instance_id);

    rv = apr_proc_mutex_create(mutex, fname, mxcfg->mech, p);
    if (rv != APR_SUCCESS) {
        log_create_failure(rv, s, type, fname);
        return rv;
    }

#ifdef AP_NEED_SET_MUTEX_PERMS
    rv = ap_unixd_set_proc_mutex_perms(*mutex);
    if (rv != APR_SUCCESS) {
        log_perms_failure(rv, s, type);
        return rv;
    }
#endif

    return APR_SUCCESS;
}