httpd/server/log.c

	log.c revision cf8fe49d9d89cfa4b62cb2b1376ca6f25b81b362
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim/* ====================================================================
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * The Apache Software License, Version 1.1
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * Copyright (c) 2000-2002 The Apache Software Foundation.  All rights
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * reserved.
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * Redistribution and use in source and binary forms, with or without
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * modification, are permitted provided that the following conditions
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * are met:
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * 1. Redistributions of source code must retain the above copyright
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *    notice, this list of conditions and the following disclaimer.
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * 2. Redistributions in binary form must reproduce the above copyright
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *    notice, this list of conditions and the following disclaimer in
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *    the documentation and/or other materials provided with the
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *    distribution.
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * 3. The end-user documentation included with the redistribution,
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *    if any, must include the following acknowledgment:
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *       "This product includes software developed by the
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *        Apache Software Foundation (http://www.apache.org/)."
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *    Alternately, this acknowledgment may appear in the software itself,
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *    if and wherever such third-party acknowledgments normally appear.
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * 4. The names "Apache" and "Apache Software Foundation" must
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *    not be used to endorse or promote products derived from this
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *    software without prior written permission. For written
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *    permission, please contact apache@apache.org.
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * 5. Products derived from this software may not be called "Apache",
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *    nor may "Apache" appear in their name, without prior written
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *    permission of the Apache Software Foundation.
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * SUCH DAMAGE.
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * ====================================================================
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * This software consists of voluntary contributions made by many
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * individuals on behalf of the Apache Software Foundation.  For more
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * information on the Apache Software Foundation, please see
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * <http://www.apache.org/>.
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * Portions of this software are based upon public domain software
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * originally written at the National Center for Supercomputing Applications,
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * University of Illinois, Urbana-Champaign.
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim */
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim/*
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * http_log.c: Dealing with the logs and errors
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim * Rob McCool
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim *
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim */
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#include "apr.h"
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#include "apr_general.h"        /* for signal stuff */
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#include "apr_strings.h"
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#include "apr_errno.h"
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#include "apr_thread_proc.h"
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#include "apr_lib.h"
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#include "apr_signal.h"
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#define APR_WANT_STDIO
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#define APR_WANT_STRFUNC
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#include "apr_want.h"
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#if APR_HAVE_STDARG_H
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#include <stdarg.h>
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#endif
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#if APR_HAVE_UNISTD_H
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#include <unistd.h>
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#endif
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#define CORE_PRIVATE
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#include "ap_config.h"
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#include "httpd.h"
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#include "http_config.h"
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#include "http_core.h"
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#include "http_log.h"
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#include "http_main.h"
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#include "util_time.h"
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jimtypedef struct {
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    char    *t_name;
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    int      t_val;
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim} TRANS;
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jimAPR_HOOK_STRUCT(
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    APR_HOOK_LINK(error_log)
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim)
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jimint AP_DECLARE_DATA ap_default_loglevel = DEFAULT_LOGLEVEL;
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#ifdef HAVE_SYSLOG
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jimstatic const TRANS facilities[] = {
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    {"auth",    LOG_AUTH},
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#ifdef LOG_AUTHPRIV
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    {"authpriv",LOG_AUTHPRIV},
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#endif
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#ifdef LOG_CRON
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    {"cron",    LOG_CRON},
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#endif
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#ifdef LOG_DAEMON
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    {"daemon",  LOG_DAEMON},
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#endif
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#ifdef LOG_FTP
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    {"ftp", LOG_FTP},
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#endif
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#ifdef LOG_KERN
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    {"kern",    LOG_KERN},
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#endif
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#ifdef LOG_LPR
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    {"lpr", LOG_LPR},
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#endif
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#ifdef LOG_MAIL
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    {"mail",    LOG_MAIL},
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#endif
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#ifdef LOG_NEWS
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    {"news",    LOG_NEWS},
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#endif
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#ifdef LOG_SYSLOG
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    {"syslog",  LOG_SYSLOG},
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#endif
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#ifdef LOG_USER
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    {"user",    LOG_USER},
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#endif
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#ifdef LOG_UUCP
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    {"uucp",    LOG_UUCP},
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#endif
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#ifdef LOG_LOCAL0
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    {"local0",  LOG_LOCAL0},
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#endif
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#ifdef LOG_LOCAL1
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    {"local1",  LOG_LOCAL1},
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#endif
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#ifdef LOG_LOCAL2
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    {"local2",  LOG_LOCAL2},
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#endif
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#ifdef LOG_LOCAL3
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    {"local3",  LOG_LOCAL3},
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#endif
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#ifdef LOG_LOCAL4
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    {"local4",  LOG_LOCAL4},
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#endif
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#ifdef LOG_LOCAL5
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    {"local5",  LOG_LOCAL5},
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#endif
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#ifdef LOG_LOCAL6
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    {"local6",  LOG_LOCAL6},
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#endif
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#ifdef LOG_LOCAL7
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    {"local7",  LOG_LOCAL7},
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim#endif
67139e2d50d1e11558d87f7042f61cb04bb0d1d2jim    {NULL,      -1},
};
#endif

static const TRANS priorities[] = {
    {"emerg",   APLOG_EMERG},
    {"alert",   APLOG_ALERT},
    {"crit",    APLOG_CRIT},
    {"error",   APLOG_ERR},
    {"warn",    APLOG_WARNING},
    {"notice",  APLOG_NOTICE},
    {"info",    APLOG_INFO},
    {"debug",   APLOG_DEBUG},
    {NULL,      -1},
};

static apr_file_t *stderr_log = NULL;

AP_DECLARE(void) ap_open_stderr_log(apr_pool_t *p)
{
    apr_file_open_stderr(&stderr_log, p);
}

static int log_child(apr_pool_t *p, const char *progname,
                     apr_file_t **fpin)
{
    /* Child process code for 'ErrorLog "|..."';
     * may want a common framework for this, since I expect it will
     * be common for other foo-loggers to want this sort of thing...
     */
    apr_status_t rc;
    apr_procattr_t *procattr;
    apr_proc_t *procnew;

    if (((rc = apr_procattr_create(&procattr, p)) == APR_SUCCESS)
        && ((rc = apr_procattr_io_set(procattr,
                                      APR_FULL_BLOCK,
                                      APR_NO_PIPE,
                                      APR_NO_PIPE)) == APR_SUCCESS)) {
        char **args;
        const char *pname;

        apr_tokenize_to_argv(progname, &args, p);
        pname = apr_pstrdup(p, args[0]);
        procnew = (apr_proc_t *)apr_pcalloc(p, sizeof(*procnew));
        rc = apr_proc_create(procnew, pname, (const char * const *)args,
                             NULL, procattr, p);

        if (rc == APR_SUCCESS) {
            apr_pool_note_subprocess(p, procnew, APR_KILL_AFTER_TIMEOUT);
            (*fpin) = procnew->in;
        }
    }

    return rc;
}

static void open_error_log(server_rec *s, apr_pool_t *p)
{
    const char *fname;
    int rc;

    if (*s->error_fname == '|') {
        apr_file_t *dummy = NULL;

        /* This starts a new process... */
        rc = log_child (p, s->error_fname + 1, &dummy);
        if (rc != APR_SUCCESS) {
            ap_log_error(APLOG_MARK, APLOG_STARTUP, rc, NULL,
                         "Couldn't start ErrorLog process");
            exit(1);
        }

        s->error_log = dummy;
    }

#ifdef HAVE_SYSLOG
    else if (!strncasecmp(s->error_fname, "syslog", 6)) {
        if ((fname = strchr(s->error_fname, ':'))) {
            const TRANS *fac;

            fname++;
            for (fac = facilities; fac->t_name; fac++) {
                if (!strcasecmp(fname, fac->t_name)) {
                    openlog(ap_server_argv0, LOG_NDELAY|LOG_CONS|LOG_PID,
                            fac->t_val);
                    s->error_log = NULL;
                    return;
                }
            }
        }
        else {
            openlog(ap_server_argv0, LOG_NDELAY|LOG_CONS|LOG_PID, LOG_LOCAL7);
        }

        s->error_log = NULL;
    }
#endif
    else {
        fname = ap_server_root_relative(p, s->error_fname);
        if (!fname) {
            ap_log_error(APLOG_MARK, APLOG_STARTUP, APR_EBADPATH, NULL,
                         "%s: Invalid error log path %s.",
                         ap_server_argv0, s->error_fname);
            exit(1);
        }
        if ((rc = apr_file_open(&s->error_log, fname,
                               APR_APPEND | APR_READ | APR_WRITE | APR_CREATE,
                               APR_OS_DEFAULT, p)) != APR_SUCCESS) {
            ap_log_error(APLOG_MARK, APLOG_STARTUP, rc, NULL,
                         "%s: could not open error log file %s.",
                         ap_server_argv0, s->error_fname);
            exit(1);
        }

        apr_file_set_inherit(s->error_log);
    }
}

void ap_open_logs(server_rec *s_main, apr_pool_t *p)
{
    apr_status_t rc = APR_SUCCESS;
    server_rec *virt, *q;
    int replace_stderr;
    apr_file_t *errfile = NULL;

    open_error_log(s_main, p);

    replace_stderr = 1;
    if (s_main->error_log) {
        /* replace stderr with this new log */
        apr_file_flush(s_main->error_log);
        if ((rc = apr_file_open_stderr(&errfile, p)) == APR_SUCCESS) {
            rc = apr_file_dup2(errfile, s_main->error_log, p);
        }
        if (rc != APR_SUCCESS) {
            ap_log_error(APLOG_MARK, APLOG_CRIT, rc, s_main,
                         "unable to replace stderr with error_log");
        }
        else {
            replace_stderr = 0;
        }
    }
    /* note that stderr may still need to be replaced with something
     * because it points to the old error log, or back to the tty
     * of the submitter.
     * XXX: This is BS - /dev/null is non-portable
     */
    if (replace_stderr && freopen("/dev/null", "w", stderr) == NULL) {
        ap_log_error(APLOG_MARK, APLOG_CRIT, errno, s_main,
                     "unable to replace stderr with /dev/null");
    }

    for (virt = s_main->next; virt; virt = virt->next) {
        if (virt->error_fname) {
            for (q=s_main; q != virt; q = q->next) {
                if (q->error_fname != NULL
                    && strcmp(q->error_fname, virt->error_fname) == 0) {
                    break;
                }
            }

            if (q == virt) {
                open_error_log(virt, p);
            }
            else {
                virt->error_log = q->error_log;
            }
        }
        else {
            virt->error_log = s_main->error_log;
        }
    }
}

AP_DECLARE(void) ap_error_log2stderr(server_rec *s) {
    apr_file_t *errfile = NULL;

    apr_file_open_stderr(&errfile, s->process->pool);
    if (s->error_log != NULL) {
        apr_file_dup2(s->error_log, errfile, s->process->pool);
    }
}

static void log_error_core(const char *file, int line, int level,
                           apr_status_t status, const server_rec *s,
                           const request_rec *r, apr_pool_t *pool,
                           const char *fmt, va_list args)
{
    char errstr[MAX_STRING_LEN];
    size_t len, errstrlen;
    apr_file_t *logf = NULL;
    const char *referer;
    int level_and_mask = level & APLOG_LEVELMASK;

    if (s == NULL) {
        /*
         * If we are doing stderr logging (startup), don't log messages that are
         * above the default server log level unless it is a startup/shutdown
         * notice
         */
        if ((level_and_mask != APLOG_NOTICE)
            && (level_and_mask > ap_default_loglevel)) {
            return;
        }

        logf = stderr_log;
    }
    else if (s->error_log) {
        /*
         * If we are doing normal logging, don't log messages that are
         * above the server log level unless it is a startup/shutdown notice
         */
        if ((level_and_mask != APLOG_NOTICE)
            && (level_and_mask > s->loglevel)) {
            return;
        }

        logf = s->error_log;
    }
#ifdef TPF
    else if (tpf_child) {
        /*
         * If we are doing normal logging, don't log messages that are
         * above the server log level unless it is a startup/shutdown notice
         */
        if ((level_and_mask != APLOG_NOTICE)
            && (level_and_mask > s->loglevel)) {
            return;
        }

        logf = stderr;
    }
#endif /* TPF */
    else {
        /*
         * If we are doing syslog logging, don't log messages that are
         * above the server log level (including a startup/shutdown notice)
         */
        if (level_and_mask > s->loglevel) {
            return;
        }
    }

    if (logf && ((level & APLOG_STARTUP) != APLOG_STARTUP)) {
        errstr[0] = '[';
        ap_recent_ctime(errstr + 1, apr_time_now());
        errstr[1 + APR_CTIME_LEN - 1] = ']';
        errstr[1 + APR_CTIME_LEN    ] = ' ';
        len = 1 + APR_CTIME_LEN + 1;
    } else {
        len = 0;
    }

    if ((level & APLOG_STARTUP) != APLOG_STARTUP) {
        len += apr_snprintf(errstr + len, MAX_STRING_LEN - len,
                            "[%s] ", priorities[level_and_mask].t_name);
    }

#ifndef TPF
    if (file && level_and_mask == APLOG_DEBUG) {
#ifdef _OSD_POSIX
        char tmp[256];
        char *e = strrchr(file, '/');

        /* In OSD/POSIX, the compiler returns for __FILE__
         * a string like: __FILE__="*POSIX(/usr/include/stdio.h)"
         * (it even returns an absolute path for sources in
         * the current directory). Here we try to strip this
         * down to the basename.
         */
        if (e != NULL && e[1] != '\0') {
            apr_snprintf(tmp, sizeof(tmp), "%s", &e[1]);
            e = &tmp[strlen(tmp)-1];
            if (*e == ')') {
                *e = '\0';
            }
            file = tmp;
        }
#endif /*_OSD_POSIX*/
        len += apr_snprintf(errstr + len, MAX_STRING_LEN - len,
                            "%s(%d): ", file, line);
    }
#endif /* TPF */

    if (r && r->connection) {
        /* XXX: TODO: add a method of selecting whether logged client
         * addresses are in dotted quad or resolved form... dotted
         * quad is the most secure, which is why I'm implementing it
         * first. -djg
         */
        len += apr_snprintf(errstr + len, MAX_STRING_LEN - len,
                            "[client %s] ", r->connection->remote_ip);
    }
    if (!(level & APLOG_NOERRNO) && (status != 0)) {
        char buf[120];
        len += apr_snprintf(errstr + len, MAX_STRING_LEN - len,
                            "(%d)%s: ", status,
                            apr_strerror(status, buf, sizeof(buf)));
    }
    errstrlen = len;
    len += apr_vsnprintf(errstr + len, MAX_STRING_LEN - len, fmt, args);

    if (r && (referer = apr_table_get(r->headers_in, "Referer"))) {
        len += apr_snprintf(errstr + len, MAX_STRING_LEN - len,
                            ", referer: %s", referer);
    }

    /* NULL if we are logging to syslog */
    if (logf) {
        /* Truncate for the terminator (as apr_snprintf does) */
        if (len > MAX_STRING_LEN - sizeof(APR_EOL_STR)) {
            len = MAX_STRING_LEN - sizeof(APR_EOL_STR);
        }
        strcpy(errstr + len, APR_EOL_STR);
        apr_file_puts(errstr, logf);
        apr_file_flush(logf);
    }
#ifdef HAVE_SYSLOG
    else {
        syslog(level_and_mask, "%s", errstr);
    }
#endif

    ap_run_error_log(file, line, level, status, s, r, pool, errstr + errstrlen);
}

AP_DECLARE(void) ap_log_error(const char *file, int line, int level,
                              apr_status_t status, const server_rec *s,
                              const char *fmt, ...)
{
    va_list args;

    va_start(args, fmt);
    log_error_core(file, line, level, status, s, NULL, NULL, fmt, args);
    va_end(args);
}

AP_DECLARE(void) ap_log_perror(const char *file, int line, int level,
                               apr_status_t status, apr_pool_t *p,
                               const char *fmt, ...)
{
    va_list args;

    va_start(args, fmt);
    log_error_core(file, line, level, status, NULL, NULL, p, fmt, args);
    va_end(args);
}

AP_DECLARE(void) ap_log_rerror(const char *file, int line, int level,
                               apr_status_t status, const request_rec *r,
                               const char *fmt, ...)
{
    va_list args;

    va_start(args, fmt);
    log_error_core(file, line, level, status, r->server, r, NULL, fmt, args);

    /*
     * IF the error level is 'warning' or more severe,
     * AND there isn't already error text associated with this request,
     * THEN make the message text available to ErrorDocument and
     * other error processors.  This can be disabled by stuffing
     * something, even an empty string, into the "error-notes" cell
     * before calling this routine.
     */
    va_end(args);
    va_start(args,fmt);
    if (((level & APLOG_LEVELMASK) <= APLOG_WARNING)
        && (apr_table_get(r->notes, "error-notes") == NULL)) {
        apr_table_setn(r->notes, "error-notes",
                       ap_escape_html(r->pool, apr_pvsprintf(r->pool, fmt,
                                                             args)));
    }
    va_end(args);
}

AP_DECLARE(void) ap_log_pid(apr_pool_t *p, const char *filename)
{
    apr_file_t *pid_file = NULL;
    apr_finfo_t finfo;
    static pid_t saved_pid = -1;
    pid_t mypid;
    apr_status_t rv;
    const char *fname;

    if (!filename) {
        return;
    }

    fname = ap_server_root_relative(p, filename);
    if (!fname) {
        ap_log_error(APLOG_MARK, APLOG_STARTUP|APLOG_CRIT, APR_EBADPATH,
                     NULL, "Invalid PID file path %s, ignoring.", filename);
        return;
    }

    mypid = getpid();
    if (mypid != saved_pid
        && apr_stat(&finfo, fname, APR_FINFO_MTIME, p) == APR_SUCCESS) {
        /* AP_SIG_GRACEFUL and HUP call this on each restart.
         * Only warn on first time through for this pid.
         *
         * XXX: Could just write first time through too, although
         *      that may screw up scripts written to do something
         *      based on the last modification time of the pid file.
         */
        ap_log_perror(APLOG_MARK, APLOG_NOERRNO|APLOG_WARNING, 0, p,
                      apr_psprintf(p, "pid file %s overwritten -- Unclean "
                                   "shutdown of previous Apache run?",
                                   fname));
    }

    if ((rv = apr_file_open(&pid_file, fname,
                            APR_WRITE | APR_CREATE | APR_TRUNCATE,
                            APR_UREAD | APR_UWRITE | APR_GREAD | APR_WREAD, p))
        != APR_SUCCESS) {
        ap_log_error(APLOG_MARK, APLOG_ERR, rv, NULL,
                     "could not create %s", fname);
        ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_ERR, 0, NULL,
                     "%s: could not log pid to file %s",
                     ap_server_argv0, fname);
        exit(1);
    }
    apr_file_printf(pid_file, "%ld" APR_EOL_STR, (long)mypid);
    apr_file_close(pid_file);
    saved_pid = mypid;
}

AP_DECLARE(void) ap_log_assert(const char *szExp, const char *szFile,
                               int nLine)
{
    char time_str[APR_CTIME_LEN];

    apr_ctime(time_str, apr_time_now());
    ap_log_error(APLOG_MARK, APLOG_CRIT | APLOG_NOERRNO, 0, NULL,
                 "[%s] file %s, line %d, assertion \"%s\" failed",
                 time_str, szFile, nLine, szExp);
#if defined(WIN32)
    DebugBreak();
#else
    /* unix assert does an abort leading to a core dump */
    abort();
#endif
}

/* piped log support */

#ifdef AP_HAVE_RELIABLE_PIPED_LOGS
/* forward declaration */
static void piped_log_maintenance(int reason, void *data, apr_wait_t status);

static int piped_log_spawn(piped_log *pl)
{
    int rc;
    apr_procattr_t *procattr;
    apr_proc_t *procnew = NULL;
    apr_status_t status;

    if (((status = apr_procattr_create(&procattr, pl->p)) != APR_SUCCESS) ||
        ((status = apr_procattr_child_in_set(procattr,
                                             ap_piped_log_read_fd(pl),
                                             ap_piped_log_write_fd(pl)))
        != APR_SUCCESS)) {
        char buf[120];
        /* Something bad happened, give up and go away. */
        ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
                     "piped_log_spawn: unable to setup child process '%s': %s",
                     pl->program, apr_strerror(status, buf, sizeof(buf)));
        rc = -1;
    }
    else {
        char **args;
        const char *pname;

        apr_tokenize_to_argv(pl->program, &args, pl->p);
        pname = apr_pstrdup(pl->p, args[0]);
        procnew = apr_pcalloc(pl->p, sizeof(apr_proc_t));
        rc = apr_proc_create(procnew, pname, (const char * const *) args,
                             NULL, procattr, pl->p);

        if (rc == APR_SUCCESS) {
            /* pjr - This no longer happens inside the child, */
            /*   I am assuming that if apr_proc_create was  */
            /*   successful that the child is running.        */
            RAISE_SIGSTOP(PIPED_LOG_SPAWN);
            pl->pid = procnew;
            ap_piped_log_write_fd(pl) = procnew->in;
            apr_proc_other_child_register(procnew, piped_log_maintenance, pl,
                                          ap_piped_log_write_fd(pl), pl->p);
        }
    }

    return 0;
}


static void piped_log_maintenance(int reason, void *data, apr_wait_t status)
{
    piped_log *pl = data;
    apr_status_t stats;

    switch (reason) {
    case APR_OC_REASON_DEATH:
        pl->pid = NULL;
        apr_proc_other_child_unregister(pl);
        if (pl->program == NULL) {
            /* during a restart */
            break;
        }
        break;
    case APR_OC_REASON_LOST:
        pl->pid = NULL;
        apr_proc_other_child_unregister(pl);
        if (pl->program == NULL) {
            /* during a restart */
            break;
        }
        if ((stats = piped_log_spawn(pl)) != APR_SUCCESS) {
            /* what can we do?  This could be the error log we're having
             * problems opening up... */
            char buf[120];
            ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
                         "piped_log_maintenance: unable to respawn '%s': %s",
                         pl->program, apr_strerror(stats, buf, sizeof(buf)));
        }
        break;

    case APR_OC_REASON_UNWRITABLE:
        /* We should not kill off the pipe here, since it may only be full.
         * If it really is locked, we should kill it off manually. */
    break;

    case APR_OC_REASON_RESTART:
        pl->program = NULL;
        if (pl->pid != NULL) {
            apr_proc_kill(pl->pid, SIGTERM);
        }
        break;

    case APR_OC_REASON_UNREGISTER:
        break;
    }
}


static apr_status_t piped_log_cleanup_for_exec(void *data)
{
    piped_log *pl = data;

    apr_file_close(ap_piped_log_read_fd(pl));
    apr_file_close(ap_piped_log_write_fd(pl));
    return APR_SUCCESS;
}


static apr_status_t piped_log_cleanup(void *data)
{
    piped_log *pl = data;

    if (pl->pid != NULL) {
        apr_proc_kill(pl->pid, SIGTERM);
    }
    return piped_log_cleanup_for_exec(data);
}


AP_DECLARE(piped_log *) ap_open_piped_log(apr_pool_t *p, const char *program)
{
    piped_log *pl;

    pl = apr_palloc(p, sizeof (*pl));
    pl->p = p;
    pl->program = apr_pstrdup(p, program);
    pl->pid = NULL;
    if (apr_file_pipe_create(&ap_piped_log_read_fd(pl),
                             &ap_piped_log_write_fd(pl), p) != APR_SUCCESS) {
        return NULL;
    }
    apr_pool_cleanup_register(p, pl, piped_log_cleanup,
                              piped_log_cleanup_for_exec);
    if (piped_log_spawn(pl) == -1) {
        int save_errno = errno;
        apr_pool_cleanup_kill(p, pl, piped_log_cleanup);
        apr_file_close(ap_piped_log_read_fd(pl));
        apr_file_close(ap_piped_log_write_fd(pl));
        errno = save_errno;
        return NULL;
    }
    return pl;
}

#else /* !AP_HAVE_RELIABLE_PIPED_LOGS */

static apr_status_t piped_log_cleanup(void *data)
{
    piped_log *pl = data;

    apr_file_close(ap_piped_log_write_fd(pl));
    return APR_SUCCESS;
}

AP_DECLARE(piped_log *) ap_open_piped_log(apr_pool_t *p, const char *program)
{
    piped_log *pl;
    apr_file_t *dummy = NULL;
    int rc;

    rc = log_child(p, program, &dummy);
    if (rc != APR_SUCCESS) {
        ap_log_error(APLOG_MARK, APLOG_STARTUP, rc, NULL,
                     "Couldn't start piped log process");
        exit (1);
    }

    pl = apr_palloc(p, sizeof (*pl));
    pl->p = p;
    ap_piped_log_read_fd(pl) = NULL;
    ap_piped_log_write_fd(pl) = dummy;
    apr_pool_cleanup_register(p, pl, piped_log_cleanup, piped_log_cleanup);

    return pl;
}

#endif

AP_DECLARE(void) ap_close_piped_log(piped_log *pl)
{
    apr_pool_cleanup_run(pl->p, pl, piped_log_cleanup);
}

AP_IMPLEMENT_HOOK_VOID(error_log,
                       (const char *file, int line, int level,
                        apr_status_t status, const server_rec *s,
                        const request_rec *r, apr_pool_t *pool,
                        const char *errstr), (file, line, level,
                        status, s, r, pool, errstr))