[apple/syslog.git] / libsystem_asl.tproj / src / asl.c

/*
 * Copyright (c) 2004-2012 Apple Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 *
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this
 * file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */

#include <assert.h>
#include <string.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <unistd.h>
#include <stdarg.h>
#include <syslog.h>
#include <errno.h>
#include <limits.h>
#include <time.h>
#include <sys/time.h>
#include <sys/fcntl.h>
#include <crt_externs.h>
#include <asl.h>
#include <regex.h>
#include <notify.h>
#include <mach/mach.h>
#include <mach/std_types.h>
#include <mach/mig.h>
#include <mach/mach_types.h>
#include <sys/types.h>
#include <servers/bootstrap.h>
#include <bootstrap_priv.h>
#include <pthread.h>
#include <dispatch/dispatch.h>
#include <libkern/OSAtomic.h>
#include <asl_ipc.h>
#include "asl_core.h"
#include "asl_msg.h"
#include "asl_store.h"
#include "asl_private.h"

#define streq(A, B) (strcmp(A, B) == 0)
#define strcaseeq(A, B) (strcasecmp(A, B) == 0)

#define forever for(;;)

#define FETCH_BATCH     256

#define LEVEL_MASK   0x0000000f
#define EVAL_MASK    0x000000f0
#define EVAL_IGNORE  0x00000000
#define EVAL_ASLFILE 0x00000010
#define EVAL_SEND    0x00000020
#define EVAL_TUNNEL  0x00000040
#define EVAL_FILE    0x00000080
#define EVAL_QUOTA   0x00000100

/*
 * Clients get a max of 36000 messages per hour.
 * Their quota gets refilled at a rate of 10 messages per second.
 */
#define QUOTA_MPH 36000
#define QUOTA_MPS 10
#define QUOTA_MSG_INTERVAL 60

#define QUOTA_MSG "*** LOG MESSAGE QUOTA EXCEEDED - SOME MESSAGES FROM THIS PROCESS HAVE BEEN DISCARDED ***"
#define QUOTA_LEVEL "2"

/* forward */
time_t asl_parse_time(const char *);
const char *asl_syslog_faciliy_num_to_name(int n);
static int _asl_send_message(aslclient ac, uint32_t eval, asl_msg_t *msg, const char *mstring);
__private_extern__ asl_client_t *_asl_open_default();

/* private asl_file SPI */
__private_extern__ uint32_t asl_file_open_write_fd(int fd, asl_file_t **s);

/* notify SPI */
uint32_t notify_register_plain(const char *name, int *out_token);

/* fork handling in syslog.c */
extern void _syslog_fork_child();

typedef struct
{
        int fd;
        asl_msg_t *msg;
        dispatch_semaphore_t sem;
} asl_aux_context_t;

typedef struct
{
        int notify_count;
        int rc_change_token;
        int notify_token;
        int master_token;
        uint64_t proc_filter;
        uint64_t master_filter;
        time_t last_send;
        time_t last_oq_msg;
        uint32_t quota;
        dispatch_once_t port_lookup_once;
        mach_port_t server_port;
        char *sender;
        pthread_mutex_t lock;
        int aux_count;
        asl_aux_context_t **aux_ctx;
        asl_client_t *asl;
} _asl_global_t;


#ifndef BUILDING_VARIANT
__private_extern__ _asl_global_t _asl_global = {0, -1, -1, -1, 0LL, 0LL, 0LL, 0LL, 0, 0, MACH_PORT_NULL, NULL, PTHREAD_MUTEX_INITIALIZER, 0, NULL, NULL};

#define ASL_SERVICE_NAME "com.apple.system.logger"

/*
 * Called from the child process inside fork() to clean up
 * inherited state from the parent process.
 *
 * NB. A lock isn't required, since we're single threaded in this call.
 */
void
_asl_fork_child()
{
        _asl_global.notify_count = 0;
        _asl_global.rc_change_token = -1;
        _asl_global.master_token = -1;
        _asl_global.notify_token = -1;
        _asl_global.quota = 0;
        _asl_global.last_send = 0;
        _asl_global.last_oq_msg = 0;

        _asl_global.port_lookup_once = 0;
        _asl_global.server_port = MACH_PORT_NULL;

        pthread_mutex_init(&(_asl_global.lock), NULL);
}

/*
 * asl_remote_notify_name: returns the notification key for remote-control filter
 * changes for this process.
 */
char *
asl_remote_notify_name()
{
        pid_t pid = getpid();
        uid_t euid = geteuid();
        char *str = NULL;

        if (euid == 0) asprintf(&str, "%s.%d", NOTIFY_PREFIX_SYSTEM, pid);
        else asprintf(&str, "user.uid.%d.syslog.%d", euid, pid);

        return str;
}

static int
_asl_notify_open(int do_lock)
{
        char *notify_name;
        uint32_t status;

        if (do_lock != 0) pthread_mutex_lock(&_asl_global.lock);

        _asl_global.notify_count++;

        if (_asl_global.notify_token != -1)
        {
                if (do_lock != 0) pthread_mutex_unlock(&_asl_global.lock);
                return 0;
        }

        if (_asl_global.rc_change_token == -1)
        {
                status = notify_register_check(NOTIFY_RC, &_asl_global.rc_change_token);
                if (status != NOTIFY_STATUS_OK) _asl_global.rc_change_token = -1;
        }

        if (_asl_global.master_token == -1)
        {
                status = notify_register_plain(NOTIFY_SYSTEM_MASTER, &_asl_global.master_token);
                if (status != NOTIFY_STATUS_OK) _asl_global.master_token = -1;
        }

        notify_name = asl_remote_notify_name();
        if (notify_name != NULL)
        {
                status = notify_register_plain(notify_name, &_asl_global.notify_token);
                free(notify_name);
                if (status != NOTIFY_STATUS_OK) _asl_global.notify_token = -1;
        }

        if (do_lock != 0) pthread_mutex_unlock(&_asl_global.lock);

        if (_asl_global.notify_token == -1) return -1;
        return 0;
}

static void
_asl_notify_close()
{
        pthread_mutex_lock(&_asl_global.lock);

        if (_asl_global.notify_count > 0) _asl_global.notify_count--;

        if (_asl_global.notify_count > 0)
        {
                pthread_mutex_unlock(&_asl_global.lock);
                return;
        }

        if (_asl_global.rc_change_token >= 0) notify_cancel(_asl_global.rc_change_token);
        _asl_global.rc_change_token = -1;

        if (_asl_global.master_token >= 0) notify_cancel(_asl_global.master_token);
        _asl_global.master_token = -1;

        if (_asl_global.notify_token >= 0) notify_cancel(_asl_global.notify_token);
        _asl_global.notify_token = -1;

        pthread_mutex_unlock(&_asl_global.lock);
}

static void
_asl_global_init()
{
        if (_asl_global.server_port == MACH_PORT_NULL)
        {
                mach_port_t newport = MACH_PORT_NULL;
                char *str = getenv("ASL_DISABLE");
                if ((str == NULL) || strcmp(str, "1"))
                {
                        bootstrap_look_up2(bootstrap_port, ASL_SERVICE_NAME, &newport, 0, BOOTSTRAP_PRIVILEGED_SERVER);
                        if (newport != MACH_PORT_NULL)
                        {
                                if (!OSAtomicCompareAndSwap32Barrier(MACH_PORT_NULL, newport, (int32_t *)&_asl_global.server_port))
                                {
                                        mach_port_deallocate(mach_task_self(), newport);
                                }
                        }
                }
        }
}

static void
_asl_global_reset()
{
        mach_port_t tmp = _asl_global.server_port;
        _asl_global.server_port = MACH_PORT_NULL;
        mach_port_deallocate(mach_task_self(), tmp);
}

aslclient
asl_open(const char *ident, const char *facility, uint32_t opts)
{
        char *name, *x;
        asl_client_t *asl;

        asl = (asl_client_t *)calloc(1, sizeof(asl_client_t));
        if (asl == NULL)
        {
                errno = ENOMEM;
                return NULL;
        }

        asl->options = opts;

        asl->sock = -1;

        _asl_global_init();

        asl->pid = getpid();
        asl->uid = getuid();
        asl->gid = getgid();

        asl->filter = ASL_FILTER_MASK_UPTO(ASL_LEVEL_NOTICE);

        if (ident != NULL)
        {
                asl->name = strdup(ident);
                if (asl->name == NULL)
                {
                        if (asl->sock >= 0) close(asl->sock);
                        free(asl);
                        return NULL;
                }
        }
        else
        {
                name = *(*_NSGetArgv());
                if (name != NULL)
                {
                        x = strrchr(name, '/');
                        if (x != NULL) x++;
                        else x = name;
                        asl->name = strdup(x);
                        if (asl->name == NULL)
                        {
                                if (asl->sock >= 0) close(asl->sock);
                                free(asl);
                                return NULL;
                        }
                }
        }

        asl->facility = NULL;
        if (facility != NULL) asl->facility = strdup(facility);
        else asl->facility = strdup(asl_syslog_faciliy_num_to_name(LOG_USER));
        if (asl->facility == NULL)
        {
                if (asl->sock >= 0) close(asl->sock);
                if (asl->name != NULL) free(asl->name);
                free(asl);
                return NULL;
        }

        if (!(asl->options & ASL_OPT_NO_REMOTE)) _asl_notify_open(1);

        if (asl->options & ASL_OPT_STDERR)
        {
                /* only add stderr if it is valid */
                if (fcntl(STDERR_FILENO, F_GETFD) >= 0)
                {
                        asl_add_output_file((aslclient)asl, STDERR_FILENO, ASL_MSG_FMT_STD, ASL_TIME_FMT_LCL, ASL_FILTER_MASK_UPTO(ASL_LEVEL_DEBUG), ASL_ENCODE_SAFE);
                }
                else
                {
                        /* stderr has been closed, ignore ASL_OPT_STDERR flag */
                        asl->options &= ~ASL_OPT_STDERR;
                }
        }

        asl->refcount = 1;

        return (aslclient)asl;
}

aslclient
asl_open_from_file(int fd, const char *ident, const char *facility)
{
        char *name, *x;
        asl_client_t *asl;
        uint32_t status;

        asl = (asl_client_t *)calloc(1, sizeof(asl_client_t));
        if (asl == NULL)
        {
                errno = ENOMEM;
                return NULL;
        }

        asl->options = ASL_OPT_NO_REMOTE;
        asl->sock = -1;

        asl->pid = getpid();
        asl->uid = getuid();
        asl->gid = getgid();

        asl->filter = ASL_FILTER_MASK_UPTO(ASL_LEVEL_DEBUG);

        if (ident != NULL)
        {
                asl->name = strdup(ident);
                if (asl->name == NULL)
                {
                        free(asl);
                        return NULL;
                }
        }
        else
        {
                name = *(*_NSGetArgv());
                if (name != NULL)
                {
                        x = strrchr(name, '/');
                        if (x != NULL) x++;
                        else x = name;
                        asl->name = strdup(x);
                        if (asl->name == NULL)
                        {
                                free(asl);
                                return NULL;
                        }
                }
        }

        asl->facility = NULL;
        if (facility != NULL) asl->facility = strdup(facility);
        else asl->facility = strdup(asl_syslog_faciliy_num_to_name(LOG_USER));
        if (asl->facility == NULL)
        {
                if (asl->name != NULL) free(asl->name);
                free(asl);
                return NULL;
        }

        status = asl_file_open_write_fd(fd, &(asl->aslfile));
        if (status != ASL_STATUS_OK)
        {
                if (asl->name != NULL) free(asl->name);
                if (asl->facility != NULL) free(asl->facility);
                free(asl);
                return NULL;
        }

        asl->aslfileid = 1;
        asl->refcount = 1;

        return (aslclient)asl;
}

__private_extern__ void
asl_client_release(asl_client_t *asl)
{
        uint32_t i;

        if (asl == NULL) return;

        if (OSAtomicDecrement32(&asl->refcount) > 0) return;

        free(asl->name);
        free(asl->facility);

        if (asl->sock >= 0) close(asl->sock);
        if (!(asl->options & ASL_OPT_NO_REMOTE)) _asl_notify_close();

        for (i = 0; i < asl->out_count; i++)
        {
                free(asl->out_list[i].mfmt);
                free(asl->out_list[i].tfmt);
        }

        free(asl->out_list);

        memset(asl, 0, sizeof(asl_client_t));
        free(asl);
}

void
asl_close(aslclient ac)
{
        asl_client_release((asl_client_t *)ac);
}

__private_extern__ asl_client_t *
asl_client_retain(asl_client_t *asl)
{
        int32_t new;

        if (asl == NULL) return NULL;

        new = OSAtomicIncrement32(&asl->refcount);
        assert(new >= 1);

        return asl;
}

__private_extern__ asl_client_t *
_asl_open_default()
{
        static dispatch_once_t once;

        dispatch_once(&once, ^{
                /*
                 * Do a sleight-of-hand with ASL_OPT_NO_REMOTE to avoid a deadlock
                 * since asl_open(xxx, yyy, 0) calls _asl_notify_open(1)
                 * which locks _asl_global.lock.
                 */
                _asl_global.asl = asl_open(NULL, NULL, ASL_OPT_NO_REMOTE);

                /* Reset options to clear ASL_OPT_NO_REMOTE bit */
                if (_asl_global.asl != NULL) _asl_global.asl->options = 0;

                /* Now call _asl_notify_open(0) to finish the work */
                _asl_notify_open(0);
        });

        return _asl_global.asl;
}

/*
 * asl_add_file: write log messages to the given file descriptor
 * Log messages will be written to this file as well as to the server.
 */
int
asl_add_output_file(aslclient ac, int fd, const char *mfmt, const char *tfmt, int filter, int text_encoding)
{
        uint32_t i;
        int use_global_lock;
        asl_client_t *asl;

        use_global_lock = 0;
        asl = (asl_client_t *)ac;
        if (asl == NULL)
        {
                asl = _asl_open_default();
                if (asl == NULL) return -1;
                pthread_mutex_lock(&_asl_global.lock);
                use_global_lock = 1;
        }

        for (i = 0; i < asl->out_count; i++)
        {
                if (asl->out_list[i].fd == fd)
                {
                        /* update message format, time format, filter, and text encoding */
                        free(asl->out_list[i].mfmt);
                        asl->out_list[i].mfmt = NULL;
                        if (mfmt != NULL) asl->out_list[i].mfmt = strdup(mfmt);

                        free(asl->out_list[i].tfmt);
                        asl->out_list[i].tfmt = NULL;
                        if (tfmt != NULL) asl->out_list[i].tfmt = strdup(tfmt);

                        asl->out_list[i].encoding = text_encoding;
                        asl->out_list[i].filter = filter;

                        if (use_global_lock != 0) pthread_mutex_unlock(&_asl_global.lock);
                        return 0;
                }
        }

        if (asl->out_count == 0)
        {
                asl->out_list = (asl_out_file_t *)calloc(1, sizeof(asl_out_file_t));
        }
        else
        {
                asl->out_list = (asl_out_file_t *)reallocf(asl->out_list, (1 + asl->out_count) * sizeof(asl_out_file_t));
        }

        if (asl->out_list == NULL)
        {
                if (use_global_lock != 0) pthread_mutex_unlock(&_asl_global.lock);
                return -1;
        }

        asl->out_list[asl->out_count].fd = fd;
        asl->out_list[asl->out_count].encoding = text_encoding;
        asl->out_list[asl->out_count].filter = filter;
        if (mfmt != NULL) asl->out_list[asl->out_count].mfmt = strdup(mfmt);
        if (tfmt != NULL) asl->out_list[asl->out_count].tfmt = strdup(tfmt);

        asl->out_count++;

        if (use_global_lock != 0) pthread_mutex_unlock(&_asl_global.lock);
        return 0;
}

int
asl_set_output_file_filter(aslclient ac, int fd, int filter)
{
        uint32_t i, last;
        int use_global_lock;
        asl_client_t *asl;

        use_global_lock = 0;
        asl = (asl_client_t *)ac;
        if (asl == NULL)
        {
                asl = _asl_open_default();
                if (asl == NULL) return -1;
                pthread_mutex_lock(&_asl_global.lock);
                use_global_lock = 1;
        }

        last = 0;

        for (i = 0; i < asl->out_count; i++)
        {
                if (asl->out_list[i].fd == fd)
                {
                        /* update filter */
                        last = asl->out_list[i].filter;
                        asl->out_list[i].filter = filter;
                        break;
                }
        }

        if (use_global_lock != 0) pthread_mutex_unlock(&_asl_global.lock);
        return last;
}

/* SPI - Deprecated */
int
asl_add_output(aslclient ac, int fd, const char *mfmt, const char *tfmt, uint32_t text_encoding)
{
        return asl_add_output_file(ac, fd, mfmt, tfmt, ASL_FILTER_MASK_UPTO(ASL_LEVEL_DEBUG), text_encoding);
}

int
asl_add_log_file(aslclient ac, int fd)
{
        return asl_add_output_file(ac, fd, ASL_MSG_FMT_STD, ASL_TIME_FMT_LCL, ASL_FILTER_MASK_UPTO(ASL_LEVEL_DEBUG), ASL_ENCODE_SAFE);
}

/*
 * asl_remove_output: stop writing log messages to the given file descriptor
 */
int
asl_remove_output_file(aslclient ac, int fd)
{
        uint32_t i;
        int x, use_global_lock;
        asl_client_t *asl;

        use_global_lock = 0;
        asl = (asl_client_t *)ac;
        if (asl == NULL)
        {
                asl = _asl_open_default();
                if (asl == NULL) return -1;
                pthread_mutex_lock(&_asl_global.lock);
                use_global_lock = 1;
        }

        if (asl->out_count == 0)
        {
                if (use_global_lock != 0) pthread_mutex_unlock(&_asl_global.lock);
                return 0;
        }

        x = -1;
        for (i = 0; i < asl->out_count; i++)
        {
                if (asl->out_list[i].fd == fd)
                {
                        x = i;
                        break;
                }
        }

        if (x == -1)
        {
                if (use_global_lock != 0) pthread_mutex_unlock(&_asl_global.lock);
                return 0;
        }

        free(asl->out_list[x].mfmt);
        free(asl->out_list[x].tfmt);

        for (i = x + 1; i < asl->out_count; i++, x++)
        {
                asl->out_list[x] = asl->out_list[i];
        }

        asl->out_count--;

        if (asl->out_count == 0)
        {
                free(asl->out_list);
                asl->out_list = NULL;
        }
        else
        {
                asl->out_list = (asl_out_file_t *)reallocf(asl->out_list, asl->out_count * sizeof(asl_out_file_t));

                if (asl->out_list == NULL)
                {
                        asl->out_count = 0;
                        if (use_global_lock != 0) pthread_mutex_unlock(&_asl_global.lock);
                        return -1;
                }
        }

        if (use_global_lock != 0) pthread_mutex_unlock(&_asl_global.lock);
        return 0;
}

int
asl_remove_output(aslclient ac, int fd)
{
        return asl_remove_output_file(ac, fd);
}

int
asl_remove_log_file(aslclient ac, int fd)
{
        return asl_remove_output_file(ac, fd);
}

int
asl_set_filter(aslclient ac, int f)
{
        int last, use_global_lock;
        asl_client_t *asl;

        use_global_lock = 0;
        asl = (asl_client_t *)ac;
        if (asl == NULL)
        {
                asl = _asl_open_default();
                if (asl == NULL) return -1;
                pthread_mutex_lock(&_asl_global.lock);
                use_global_lock = 1;
        }

        last = asl->filter;
        asl->filter = f;

        if (use_global_lock != 0) pthread_mutex_unlock(&_asl_global.lock);
        return last;
}

/*
 * Evaluate client / message / level to determine what to do with a message.
 * Checks filters, tunneling, and log files.  Returns EVAL_IGNORE if the message
 * can be ignored.  Otherwise it returns the bits below, ORed with the level.
 *
 * EVAL_ASLFILE - will write to an asl file (see asl_open_from_file)
 * EVAL_SEND - will send to syslogd
 * EVAL_TUNNEL - will send to syslogd with tunneling enabled
 * EVAL_FILE - will write to file
 */
uint32_t
_asl_evaluate_send(aslclient ac, aslmsg msg, int slevel)
{
        asl_client_t *asl = (asl_client_t *)ac;
        uint32_t level, lmask, filter, status, tunnel;
        int check, out;
        uint64_t v64;
        const char *val;

        if (asl == NULL)
        {
                asl = _asl_open_default();
                if (asl == NULL) return EVAL_IGNORE;
        }

        check = ASL_LEVEL_DEBUG;
        if (slevel >= 0) check = slevel;

        val = asl_get((aslmsg)msg, ASL_KEY_LEVEL);
        if (val != NULL) check = atoi(val);

        if (check < ASL_LEVEL_EMERG) check = ASL_LEVEL_EMERG;
        else if (check > ASL_LEVEL_DEBUG) check = ASL_LEVEL_DEBUG;
        level = check;

        out = check;

        if (asl->aslfile != NULL) return (out | EVAL_ASLFILE);

        lmask = ASL_FILTER_MASK(level);

        filter = asl->filter & 0xff;
        tunnel = (asl->filter & ASL_FILTER_MASK_TUNNEL) >> 8;
        
        if (!(asl->options & ASL_OPT_NO_REMOTE))
        {
                pthread_mutex_lock(&_asl_global.lock);

                if (_asl_global.rc_change_token >= 0)
                {
                        /* initialize or re-check process-specific and master filters  */
                        check = 0;
                        status = notify_check(_asl_global.rc_change_token, &check);
                        if ((status == NOTIFY_STATUS_OK) && (check != 0))
                        {
                                if (_asl_global.master_token >= 0)
                                {
                                        v64 = 0;
                                        status = notify_get_state(_asl_global.master_token, &v64);
                                        if (status == NOTIFY_STATUS_OK) _asl_global.master_filter = v64;
                                }

                                if (_asl_global.notify_token >= 0)
                                {
                                        v64 = 0;
                                        status = notify_get_state(_asl_global.notify_token, &v64);
                                        if (status == NOTIFY_STATUS_OK) _asl_global.proc_filter = v64;
                                }
                        }
                }

                pthread_mutex_unlock(&_asl_global.lock);

                /* master filter overrides local filter */
                if (_asl_global.master_filter != 0)
                {
                        filter = _asl_global.master_filter;
                        tunnel = 1;
                }

                /* process-specific filter overrides local and master */
                if (_asl_global.proc_filter != 0)
                {
                        filter = _asl_global.proc_filter;
                        tunnel = 1;
                }
        }

        if ((filter != 0) && ((filter & lmask) != 0))
        {
                out |= EVAL_SEND;
                if (tunnel != 0) out |= EVAL_TUNNEL;
                if (asl->out_count > 0) out |= EVAL_FILE;

                return out;
        }

        if ((asl->options & ASL_OPT_SYSLOG_LEGACY) && (filter != 0) && ((filter & lmask) == 0))
        {
                return EVAL_IGNORE;
        }

        if (asl->out_count > 0) return (out | EVAL_FILE);

        return EVAL_IGNORE;
}

#endif /* BUILDING_VARIANT */

/*
 * _asl_lib_vlog
 * Internal routine used by asl_vlog.
 * msg:  an aslmsg
 * eval: log level and send flags for the message
 * format: A formating string
 * ap: va_list for the format
 * returns 0 for success, non-zero for failure
 */
static int
_asl_lib_vlog(aslclient ac, uint32_t eval, aslmsg msg, const char *format, va_list ap)
{
        int saved_errno = errno;
        int status;
        char *str, *fmt, estr[NL_TEXTMAX];
        uint32_t i, len, elen, expand;
        asl_client_t *asl;

        asl = (asl_client_t *)ac;
        if (asl == NULL)
        {
                /*
                 * Initialize _asl_global so that asl_new will have global data.
                 * Not strictly necessary, but helps performance.
                 */
                asl = _asl_open_default();
                if (asl == NULL) return -1;
        }

        if (format == NULL) return -1;

        /* insert strerror for %m */
        len = 0;
        elen = 0;

        expand = 0;
        for (i = 0; format[i] != '\0'; i++)
        {
                if (format[i] == '%')
                {
                        if (format[i+1] == '\0') len++;
                        else if (format[i+1] == 'm')
                        {
                                expand = 1;
                                strerror_r(saved_errno, estr, sizeof(estr));
                                elen = strlen(estr);
                                len += elen;
                                i++;
                        }
                        else
                        {
                                len += 2;
                                i++;
                        }
                }
                else len++;
        }

        fmt = (char *)format;

        if (expand != 0)
        {
                fmt = malloc(len + 1);
                if (fmt == NULL)
                {
                        if (estr != NULL) free(estr);
                        return -1;
                }

                len = 0;

                for (i = 0; format[i] != '\0'; i++)
                {
                        if (format[i] == '%')
                        {
                                if (format[i+1] == '\0')
                                {
                                }
                                else if ((format[i+1] == 'm') && (elen != 0))
                                {
                                        memcpy(fmt+len, estr, elen);
                                        len += elen;
                                        i++;
                                }
                                else
                                {
                                        fmt[len++] = format[i++];
                                        fmt[len++] = format[i];
                                }
                        }
                        else fmt[len++] = format[i];
                }

                fmt[len] = '\0';
        }

        str = NULL;
        vasprintf(&str, fmt, ap);
        if (expand != 0) free(fmt);

        if (str == NULL) return -1;

        status = _asl_send_message(ac, eval, (asl_msg_t *)msg, str);
        free(str);

        return status;
}

/*
 * asl_vlog
 * Similar to asl_log, but take a va_list instead of a list of arguments.
 * msg:  an aslmsg
 * level: the log level of the associated message
 * format: A formating string
 * ap: va_list for the format
 * returns 0 for success, non-zero for failure
 */
int
asl_vlog(aslclient ac, aslmsg msg, int level, const char *format, va_list ap)
{
        uint32_t eval = _asl_evaluate_send(ac, msg, level);
        if (eval == EVAL_IGNORE) return 0;

        return _asl_lib_vlog(ac, eval, msg, format, ap);
}

/*
 * _asl_lib_log
 * SPI used by ASL_PREFILTER_LOG. Converts format arguments to a va_list and
 * forwards the call to _asl_lib_vlog.
 * msg:  an aslmsg
 * eval: log level and send flags for the message
 * format: A formating string
 * ... args for format
 * returns 0 for success, non-zero for failure
 */
int
_asl_lib_log(aslclient ac, uint32_t eval, aslmsg msg, const char *format, ...)
{
        int status;
        if (eval == EVAL_IGNORE) return 0;

        va_list ap;
        va_start(ap, format);
        status = _asl_lib_vlog(ac, eval, msg, format, ap);
        va_end(ap);

        return status;
}

/*
 * asl_log
 * Processes an ASL log message.
 * msg:  an aslmsg
 * level: the log level of the associated message
 * format: A formating string
 * ... args for format
 * returns 0 for success, non-zero for failure
 */
int
asl_log(aslclient ac, aslmsg msg, int level, const char *format, ...)
{
        int status;
        uint32_t eval = _asl_evaluate_send(ac, msg, level);
        if (eval == EVAL_IGNORE) return 0;

        va_list ap;
        va_start(ap, format);
        status = _asl_lib_vlog(ac, eval, msg, format, ap);
        va_end(ap);

        return status;
}

#ifndef BUILDING_VARIANT

/*
 * asl_get_filter: gets the values for the local, master, and remote filters, 
 * and indicates which one is active.
 */
int
asl_get_filter(aslclient ac, int *local, int *master, int *remote, int *active)
{
        asl_client_t *asl, *asl_default;
        int l, m, r, x;
        int status, check;
        uint64_t v64;

        l = 0;
        m = 0;
        r = 0;
        x = 0;

        asl_default = _asl_open_default();

        asl = (asl_client_t *)ac;
        if (asl == NULL) asl = asl_default;
        if (asl != NULL) l = asl->filter & 0xff;

        if ((asl_default != NULL) && (!(asl_default->options & ASL_OPT_NO_REMOTE)))
        {
                pthread_mutex_lock(&_asl_global.lock);

                if (_asl_global.rc_change_token >= 0)
                {
                        /* initialize or re-check process-specific and master filters  */
                        check = 0;
                        status = notify_check(_asl_global.rc_change_token, &check);
                        if ((status == NOTIFY_STATUS_OK) && (check != 0))
                        {
                                if (_asl_global.master_token >= 0)
                                {
                                        v64 = 0;
                                        status = notify_get_state(_asl_global.master_token, &v64);
                                        if (status == NOTIFY_STATUS_OK) _asl_global.master_filter = v64;
                                }

                                if (_asl_global.notify_token >= 0)
                                {
                                        v64 = 0;
                                        status = notify_get_state(_asl_global.notify_token, &v64);
                                        if (status == NOTIFY_STATUS_OK) _asl_global.proc_filter = v64;
                                }
                        }
                }

                m = _asl_global.master_filter;
                if (m != 0) x = 1;

                r = _asl_global.proc_filter;
                if (r != 0) x = 2;

                pthread_mutex_unlock(&_asl_global.lock);
        }

        if (local != NULL) *local = l;
        if (master != NULL) *master = m;
        if (remote != NULL) *remote = r;
        if (active != NULL) *active = x;

        return 0;
}

static int
_asl_send_message(aslclient ac, uint32_t eval, asl_msg_t *msg, const char *mstring)
{
        uint32_t i, len, level, lmask, outstatus;
        const char *val;
        char *name, *x;
        time_t tick;
        struct timeval tval;
        int status;
        asl_client_t *asl;
        int use_global_lock;
        kern_return_t kstatus;
        char aux_val[64];
        char aux_host[_POSIX_HOST_NAME_MAX];
        asl_msg_t *aux;

        if (eval == EVAL_IGNORE) return 0;

        level = eval & LEVEL_MASK;
        eval &= EVAL_MASK;
        lmask = ASL_FILTER_MASK(level);

        use_global_lock = 0;
        asl = (asl_client_t *)ac;
        if (asl == NULL)
        {
                asl = _asl_open_default();
                if (asl == NULL) return -1;
                use_global_lock = 1;
        }

        if (asl->aslfile != NULL) use_global_lock = 1;

        /* 
         * Time, TimeNanoSec, Host, PID, UID, and GID values get set here.
         * Also sets Sender & Facility (if unset) and "ASLOption store" if remote control is active.
         */
        aux = asl_msg_new(ASL_TYPE_MSG);

        if (mstring != NULL) asl_msg_set_key_val(aux, ASL_KEY_MSG, mstring);

        snprintf(aux_val, sizeof(aux_val), "%u", level);
        asl_msg_set_key_val(aux, ASL_KEY_LEVEL, aux_val);

        memset(&tval, 0, sizeof(struct timeval));

        status = gettimeofday(&tval, NULL);
        if (status == 0)
        {
                snprintf(aux_val, sizeof(aux_val), "%lu", tval.tv_sec);
                asl_msg_set_key_val(aux, ASL_KEY_TIME, aux_val);
                snprintf(aux_val, sizeof(aux_val), "%d", tval.tv_usec * 1000);
                asl_msg_set_key_val(aux, ASL_KEY_TIME_NSEC, aux_val);
        }
        else
        {
                tick = time(NULL);
                snprintf(aux_val, sizeof(aux_val), "%lu", tick);
                asl_msg_set_key_val(aux, ASL_KEY_TIME, aux_val);
        }

        memset(&aux_host, 0, _POSIX_HOST_NAME_MAX);
        if (gethostname(aux_host, _POSIX_HOST_NAME_MAX) == 0)
        {
                asl_msg_set_key_val(aux, ASL_KEY_HOST, aux_host);
        }

        snprintf(aux_val, sizeof(aux_val), "%u", getpid());
        asl_msg_set_key_val(aux, ASL_KEY_PID, aux_val);

        snprintf(aux_val, sizeof(aux_val), "%d", getuid());
        asl_msg_set_key_val(aux, ASL_KEY_UID, aux_val);

        snprintf(aux_val, sizeof(aux_val), "%d", getgid());
        asl_msg_set_key_val(aux, ASL_KEY_GID, aux_val);

        /*
         * Set Sender if needed
         */
        status = asl_msg_lookup((asl_msg_t *)msg, ASL_KEY_SENDER, &val, NULL);
        if ((status != 0) || (val == NULL))
        {
                if ((ac != NULL) && (ac->name != NULL))
                {
                        /* Use the Sender name from the client handle */
                        asl_msg_set_key_val(aux, ASL_KEY_SENDER, ac->name);
                }
                else
                {
                        /* Get the value for ASL_KEY_SENDER from cache */
                        if (_asl_global.sender == NULL)
                        {
                                name = *(*_NSGetArgv());
                                if (name != NULL)
                                {
                                        x = strrchr(name, '/');
                                        if (x != NULL) x++;
                                        else x = name;

                                        pthread_mutex_lock(&_asl_global.lock);
                                        if (_asl_global.sender == NULL) _asl_global.sender = strdup(x);
                                        pthread_mutex_unlock(&_asl_global.lock);
                                }
                        }

                        if (_asl_global.sender != NULL) asl_msg_set_key_val(aux, ASL_KEY_SENDER, _asl_global.sender);
                        else asl_msg_set_key_val(aux, ASL_KEY_SENDER, "Unknown");
                }
        }

        /*
         * Set Facility
         */
        status = asl_msg_lookup((asl_msg_t *)msg, ASL_KEY_FACILITY, &val, NULL);
        if ((status != 0) || (val == NULL))
        {
                if ((ac != NULL) && (ac->facility != NULL))
                {
                        /* Use the Facility name from the client handle */
                        asl_msg_set_key_val(aux, ASL_KEY_FACILITY, ac->facility);
                }
        }

        /* Set "ASLOption store" if tunneling */

        if (eval & EVAL_TUNNEL)
        {
                val = asl_get((aslmsg)msg, ASL_KEY_OPTION);
                if (val == NULL)
                {
                        asl_msg_set_key_val(aux, ASL_KEY_OPTION, ASL_OPT_STORE);
                }
                else
                {
                        char *aux_option = NULL;
                        asprintf(&aux_option, "%s %s", ASL_OPT_STORE, val);
                        asl_msg_set_key_val(aux, ASL_KEY_OPTION, aux_option);
                        free(aux_option);
                }
        }

        outstatus = -1;

        if (use_global_lock != 0) pthread_mutex_lock(&_asl_global.lock);

        aux = asl_msg_merge(aux, msg);

        /*
         * If there is an aslfile this is a stand-alone file client.
         * Just save to the file.
         */
        if (asl->aslfile != NULL)
        {
                outstatus = ASL_STATUS_FAILED;

                if (aux != NULL)
                {
                        outstatus = asl_file_save(asl->aslfile, (aslmsg)aux, &(asl->aslfileid));
                        asl->aslfileid++;
                }

                asl_msg_release(aux);

                if (use_global_lock != 0) pthread_mutex_unlock(&_asl_global.lock);
                return outstatus;
        }

        _asl_global_init();
        outstatus = 0;

        /* manage quota */
        if ((eval & EVAL_TUNNEL) == 0)
        {
                time_t last_send = _asl_global.last_send;
                time_t last_oq = _asl_global.last_oq_msg;
                uint32_t qcurr = _asl_global.quota;
                time_t delta;
                uint32_t qinc, qnew;

                qnew = qcurr;

                /* add QUOTA_MPS to quota for each second we've been idle */
                if (tval.tv_sec > last_send)
                {
                        delta = tval.tv_sec - last_send;

                        qinc = QUOTA_MPH;
                        if (delta < (QUOTA_MPH / QUOTA_MPS)) qinc = delta * QUOTA_MPS;

                        qnew = MIN(QUOTA_MPH, qcurr + qinc);
                        OSAtomicCompareAndSwapLongBarrier(last_send, tval.tv_sec, (long *)&_asl_global.last_send);
                }

                if (qnew == 0)
                {
                        if ((tval.tv_sec - last_oq) > QUOTA_MSG_INTERVAL)
                        {
                                eval |= EVAL_QUOTA;
                                OSAtomicCompareAndSwapLongBarrier(last_oq, tval.tv_sec, (long *)&_asl_global.last_oq_msg);
                        }
                        else
                        {
                                eval &= ~EVAL_SEND;
                        }
                }
                else
                {
                        OSAtomicCompareAndSwap32Barrier(qcurr, qnew - 1, (int32_t *)&_asl_global.quota);
                }
        }

        if ((_asl_global.server_port != MACH_PORT_NULL) && (eval & EVAL_SEND))
        {
                asl_string_t *send_str;
                const char *str;
                size_t vmsize;

                if (eval & EVAL_QUOTA)
                {
                        asl_msg_set_key_val(aux, ASL_KEY_LEVEL, QUOTA_LEVEL);
                        asl_msg_set_key_val(aux, ASL_KEY_MSG, QUOTA_MSG);
                }

                send_str = asl_msg_to_string_raw(ASL_STRING_MIG, aux, "raw");
                len = asl_string_length(send_str);
                vmsize = asl_string_allocated_size(send_str);
                str = asl_string_free_return_bytes(send_str);

                if (len != 0)
                {
                        /* send a mach message to syslogd */
                        kstatus = _asl_server_message(_asl_global.server_port, (caddr_t)str, len);
                        if (kstatus != KERN_SUCCESS)
                        {
                                /* retry once if the call failed */
                                _asl_global_reset();
                                _asl_global_init();
                                kstatus = _asl_server_message(_asl_global.server_port, (caddr_t)str, len);
                                if (kstatus != KERN_SUCCESS)
                                {
                                        _asl_global_reset();
                                        vm_deallocate(mach_task_self(), (vm_address_t)str, vmsize);
                                        outstatus = -1;
                                }
                        }
                }
                else if (vmsize >0) vm_deallocate(mach_task_self(), (vm_address_t)str, vmsize);
        }

        if ((aux != NULL) && (asl->out_count > 0))
        {
                /* write to file descriptors */
                for (i = 0; i < asl->out_count; i++)
                {
                        if ((asl->out_list[i].fd >= 0) && (asl->out_list[i].filter != 0) && ((asl->out_list[i].filter & lmask) != 0))
                        {
                                char *str;

                                len = 0;
                                str = asl_format_message(aux, asl->out_list[i].mfmt, asl->out_list[i].tfmt, asl->out_list[i].encoding, &len);
                                if (str == NULL) continue;

                                status = write(asl->out_list[i].fd, str, len - 1);
                                if (status < 0)
                                {
                                        /* soft error for fd 2 (stderr) */
                                        if (asl->out_list[i].fd != 2) outstatus = -1;
                                        asl->out_list[i].fd = -1;
                                }

                                free(str);
                        }
                }
        }

        asl_msg_release(aux);

        if (use_global_lock != 0) pthread_mutex_unlock(&_asl_global.lock);

        return outstatus;
}

/*
 * asl_send: send a message 
 * This routine may be used instead of asl_log() or asl_vlog() if asl_set() 
 * has been used to set all of a message's attributes.
 * eval:  hints about what to do with the message
 * msg:  an aslmsg
 * returns 0 for success, non-zero for failure
 */
int
asl_send(aslclient ac, aslmsg msg)
{
        int status = 0;
        uint32_t eval = _asl_evaluate_send(ac, msg, -1);
        if (eval != 0) status = _asl_send_message(ac, eval, (asl_msg_t *)msg, NULL);

        return status;
}

static int
_asl_aux_save_context(asl_aux_context_t *ctx)
{
        if (ctx == NULL) return -1;

        pthread_mutex_lock(&_asl_global.lock);

        _asl_global.aux_ctx = (asl_aux_context_t **)reallocf(_asl_global.aux_ctx, (_asl_global.aux_count + 1) * sizeof(asl_aux_context_t *));
        if (_asl_global.aux_ctx == NULL)
        {
                _asl_global.aux_count = 0;
                return -1;
        }

        _asl_global.aux_ctx[_asl_global.aux_count++] = ctx;

        pthread_mutex_unlock(&_asl_global.lock);

        return 0;
}

/*
 * Creates an auxiliary file that may be used to save arbitrary data.  The ASL message msg
 * will be saved at the time that the auxiliary file is created.  The message will include
 * any keys and values found in msg, and it will include the title and Uniform Type
 * Identifier specified.  Output parameter out_fd will contain the file descriptor of the
 * new auxiliary file.
 */
static int
_asl_auxiliary(asl_msg_t *msg, const char *title, const char *uti, const char *url, int *out_fd)
{
        asl_msg_t *aux;
        asl_string_t *send_str;
        const char *str;
        fileport_t fileport;
        kern_return_t kstatus;
        size_t len, vmsize;
        uint32_t newurllen, where;
        int status, fd, fdpair[2];
        caddr_t newurl;
        dispatch_queue_t pipe_q;
        dispatch_io_t pipe_channel;
        dispatch_semaphore_t sem;

        aux = asl_msg_new(ASL_TYPE_MSG);

        if (title != NULL)
        {
                asl_msg_set_key_val(aux, ASL_KEY_AUX_TITLE, title);
        }

        if (uti == NULL)
        {
                asl_msg_set_key_val(aux, ASL_KEY_AUX_UTI, "public.data");
        }
        else
        {
                asl_msg_set_key_val(aux, ASL_KEY_AUX_UTI, uti);
        }

        if (url != NULL)
        {
                asl_msg_set_key_val(aux, ASL_KEY_AUX_URL, url);
        }

        aux = asl_msg_merge(aux, msg);

        /* if (out_fd == NULL), this is from asl_log_auxiliary_location */
        if (out_fd == NULL)
        {
                uint32_t eval = _asl_evaluate_send(NULL, (aslmsg)aux, -1);
                status = _asl_send_message(NULL, eval, aux, NULL);
                asl_msg_release(aux);
                return status;
        }

        where = asl_store_location();

        if (where == ASL_STORE_LOCATION_MEMORY)
        {
                /* create a pipe */

                asl_aux_context_t *ctx = (asl_aux_context_t *)calloc(1, sizeof(asl_aux_context_t));
                if (ctx == NULL) return -1;

                status = pipe(fdpair);
                if (status < 0)
                {
                        free(ctx);
                        return -1;
                }

                /* give read end to dispatch_io_read */
                fd = fdpair[0];
                sem = dispatch_semaphore_create(0);
                ctx->sem = sem;
                ctx->fd = fdpair[1];

                status = _asl_aux_save_context(ctx);
                if (status != 0)
                {
                        close(fdpair[0]);
                        close(fdpair[1]);
                        dispatch_release(sem);
                        free(ctx);
                        return -1;
                }

                pipe_q = dispatch_queue_create("PipeQ", NULL);
                pipe_channel = dispatch_io_create(DISPATCH_IO_STREAM, fd, pipe_q, ^(int err){
                        close(fd);
                });

                *out_fd = fdpair[1];

                dispatch_io_set_low_water(pipe_channel, SIZE_MAX);

                dispatch_io_read(pipe_channel, 0, SIZE_MAX, pipe_q, ^(bool done, dispatch_data_t pipedata, int err){
                        if (err == 0)
                        {
                                size_t len = dispatch_data_get_size(pipedata);
                                if (len > 0)
                                {
                                        const char *bytes = NULL;
                                        char *encoded;
                                        uint32_t eval;

                                        dispatch_data_t md = dispatch_data_create_map(pipedata, (const void **)&bytes, &len);
                                        encoded = asl_core_encode_buffer(bytes, len);
                                        asl_msg_set_key_val(aux, ASL_KEY_AUX_DATA, encoded);
                                        free(encoded);
                                        eval = _asl_evaluate_send(NULL, (aslmsg)aux, -1);
                                        _asl_send_message(NULL, eval, aux, NULL);
                                        asl_msg_release(aux);
                                        dispatch_release(md);
                                }
                        }

                        if (done)
                        {
                                dispatch_semaphore_signal(sem);
                                dispatch_release(pipe_channel);
                                dispatch_release(pipe_q);
                        }
                });

                return 0;
        }

        _asl_global_init();
        if (_asl_global.server_port == MACH_PORT_NULL) return -1;

        send_str = asl_msg_to_string_raw(ASL_STRING_MIG, aux, "raw");
        len = asl_string_length(send_str);
        vmsize = asl_string_allocated_size(send_str);
        str = asl_string_free_return_bytes(send_str);

        if (len == 0) 
        {
                asl_msg_release(aux);
                vm_deallocate(mach_task_self(), (vm_address_t)str, vmsize);
                return -1;
        }

        status = 0;
        fileport = MACH_PORT_NULL;
        status = KERN_SUCCESS;

        kstatus = _asl_server_create_aux_link(_asl_global.server_port, (caddr_t)str, len, &fileport, &newurl, &newurllen, &status);
        if (kstatus != KERN_SUCCESS)
        {
                /* retry once if the call failed */
                _asl_global_reset();
                _asl_global_init();
                kstatus = _asl_server_create_aux_link(_asl_global.server_port, (caddr_t)str, len, &fileport, &newurl, &newurllen, &status);
                if (kstatus != KERN_SUCCESS)
                {
                        _asl_global_reset();
                        vm_deallocate(mach_task_self(), (vm_address_t)str, vmsize);
                        asl_msg_release(aux);
                        return -1;
                }
        }

        if (status != 0)
        {
                asl_msg_release(aux);
                return status;
        }

        if (newurl != NULL)
        {
                asl_msg_set_key_val(aux, ASL_KEY_AUX_URL, newurl);
                vm_deallocate(mach_task_self(), (vm_address_t)newurl, newurllen);
        }

        if (fileport == MACH_PORT_NULL)
        {
                asl_msg_release(aux);
                return -1;
        }

        fd = fileport_makefd(fileport);
        mach_port_deallocate(mach_task_self(), fileport);
        if (fd < 0)
        {
                asl_msg_release(aux);
                status = -1;
        }
        else
        {
                asl_aux_context_t *ctx = (asl_aux_context_t *)calloc(1, sizeof(asl_aux_context_t));
                if (ctx == NULL)
                {
                        status = -1;
                }
                else
                {
                        *out_fd = fd;

                        ctx->fd = fd;
                        ctx->msg = aux;

                        status = _asl_aux_save_context(ctx);
                }
        }

        return status;
}

int
asl_create_auxiliary_file(aslmsg msg, const char *title, const char *uti, int *out_fd)
{
        if (out_fd == NULL) return -1;

        return _asl_auxiliary((asl_msg_t *)msg, title, uti, NULL, out_fd);
}

int
asl_log_auxiliary_location(aslmsg msg, const char *title, const char *uti, const char *url)
{
        return _asl_auxiliary((asl_msg_t *)msg, title, uti, url, NULL);
}

/*
 * Close an auxiliary file.
 * Sends the cached auxiliary message to syslogd.
 */
int
asl_close_auxiliary_file(int fd)
{
        int i, j, status;
        asl_msg_t *aux_msg;
        dispatch_semaphore_t aux_sem = NULL;

        pthread_mutex_lock(&(_asl_global.lock));

        aux_msg = NULL;
        status = -1;

        for (i = 0; i < _asl_global.aux_count; i++)
        {
                if (_asl_global.aux_ctx[i]->fd == fd)
                {
                        status = 0;

                        aux_msg = _asl_global.aux_ctx[i]->msg;
                        aux_sem = _asl_global.aux_ctx[i]->sem;

                        free(_asl_global.aux_ctx[i]);

                        for (j = i + 1; j < _asl_global.aux_count; i++, j++)
                        {
                                _asl_global.aux_ctx[i] = _asl_global.aux_ctx[j];
                        }

                        _asl_global.aux_count--;

                        if (_asl_global.aux_count == 0)
                        {
                                free(_asl_global.aux_ctx);
                                _asl_global.aux_ctx = NULL;
                        }
                        else
                        {
                                _asl_global.aux_ctx = (asl_aux_context_t **)reallocf(_asl_global.aux_ctx, _asl_global.aux_count * sizeof(asl_aux_context_t *));
                                if (_asl_global.aux_ctx == NULL)
                                {
                                        _asl_global.aux_count = 0;
                                        status = -1;
                                }
                        }

                        break;
                }
        }

        pthread_mutex_unlock(&(_asl_global.lock));

        close(fd);

        if (aux_msg != NULL)
        {
                uint32_t eval = _asl_evaluate_send(NULL, (aslmsg)aux_msg, -1);
                if (_asl_send_message(NULL, eval, aux_msg, NULL) != ASL_STATUS_OK) status = -1;
                asl_msg_release(aux_msg);
        }

        if (aux_sem != NULL)
        {
                dispatch_semaphore_wait(aux_sem, DISPATCH_TIME_FOREVER);
                dispatch_release(aux_sem);
        }

        return status;
}

/*
 * asl_search: Search for messages matching the criteria described
 * by the aslmsg.  The caller should set the attributes to match using
 * asl_set_query() or asl_set().  The operatoin ASL_QUERY_OP_EQUAL is
 * used for attributes set with asl_set().
 * a:  an aslmsg
 * returns: a set of messages that can be iterated over using aslresp_next(),
 * and the values can be retrieved using aslresp_get.
 */

/*
 * This routine searches the ASL datastore on disk (/var/log/asl).
 * It is called my asl_search if syslogd is not running or if syslogd
 * indicates that an in-memory store is not being used.
 */
static aslresponse
_asl_search_store(aslclient ac, aslmsg a)
{
        asl_search_result_t query, *out;
        asl_msg_t *q, *qlist[1];
        uint32_t status, op;
        uint64_t last_id, start_id;
        asl_store_t *store;
        const char *val;

        if (a == NULL) return NULL;

        q = (asl_msg_t *)a;

        /* check for "ASLMessageId >[=] n" and set start_id */
        start_id = 0;
        val = NULL;

        status = asl_msg_lookup(q, ASL_KEY_MSG_ID, &val, &op);
        if ((status == 0) && (val != NULL) && (op & ASL_QUERY_OP_GREATER))
        {
                if (op & ASL_QUERY_OP_EQUAL) start_id = atoll(val);
                else start_id = atoll(val) + 1;
        }

        store = NULL;
        status = asl_store_open_read(NULL, &store);
        if (status != 0) return NULL;
        if (store == NULL) return NULL;

        out = NULL;
        last_id = 0;

        qlist[0] = (asl_msg_t *)a;
        memset(&query, 0, sizeof(asl_search_result_t));
        query.count = 1;
        query.msg = qlist;

        status = asl_store_match(store, &query, &out, &last_id, start_id, 0, 1);
        asl_store_close(store);

        return out;
}

static uint32_t
_asl_search_concat_results(asl_search_result_t *batch, asl_search_result_t **out)
{
        uint32_t i, j;

        if (out == NULL) return ASL_STATUS_FAILED;

        /* nothing to do if batch is NULL or contains no messages */
        if (batch == NULL) return 0;
        if (batch->count == 0)
        {
                aslresponse_free(batch);
                return 0;
        }

        if (*out == NULL) *out = (asl_search_result_t *)calloc(1, sizeof(asl_search_result_t));
        if (*out == NULL)
        {
                aslresponse_free(batch);
                return ASL_STATUS_FAILED;
        }

        if ((*out)->count == 0)
        {
                (*out)->msg = (asl_msg_t **)calloc(batch->count, sizeof(asl_msg_t *));
        }
        else
        {
                (*out)->msg = (asl_msg_t **)reallocf((*out)->msg, ((*out)->count + batch->count) * sizeof(asl_msg_t *));
        }

        if ((*out)->msg == NULL)
        {
                aslresponse_free(batch);
                free(*out);
                *out = NULL;
                return ASL_STATUS_FAILED;
        }

        for (i = 0, j = (*out)->count; i < batch->count; i++, j++) (*out)->msg[j] = batch->msg[i];

        (*out)->count += batch->count;
        free(batch->msg);
        free(batch);
        return ASL_STATUS_OK;
}

static aslresponse
_asl_search_memory(aslclient ac, aslmsg a)
{
        asl_search_result_t *batch, *out;
        char *qstr, *str, *res;
        uint32_t len, reslen, status;
        uint64_t cmax, qmin;
        kern_return_t kstatus;
        caddr_t vmstr;

        if (a == NULL) return 0;

        _asl_global_init();
        if (_asl_global.server_port == MACH_PORT_NULL) return NULL;

        len = 0;
        qstr = asl_msg_to_string((asl_msg_t *)a, &len);

        str = NULL;
        if (qstr == NULL)
        {
                asprintf(&str, "0\n");
                len = 3;
        }
        else
        {
                asprintf(&str, "1\n%s\n", qstr);
                len += 3;
                free(qstr);
        }

        if (str == NULL) return NULL;

        /*
         * Fetch a batch of results each time through the loop.
         * Fetching small batches rebuces the load on syslogd.
         */
        out = NULL;
        qmin = 0;
        cmax = 0;

        forever
        {
                res = NULL;
                reslen = 0;
                status = ASL_STATUS_OK;

                kstatus = vm_allocate(mach_task_self(), (vm_address_t *)&vmstr, len, TRUE);
                if (kstatus != KERN_SUCCESS) return NULL;

                memmove(vmstr, str, len);

                status = 0;
                kstatus = _asl_server_query_2(_asl_global.server_port, vmstr, len, qmin, FETCH_BATCH, 0, (caddr_t *)&res, &reslen, &cmax, (int *)&status);
                if (kstatus != KERN_SUCCESS)
                {
                        /* retry once if the call failed */
                        _asl_global_reset();
                        _asl_global_init();
                        kstatus = _asl_server_query_2(_asl_global.server_port, vmstr, len, qmin, FETCH_BATCH, 0, (caddr_t *)&res, &reslen, &cmax, (int *)&status);
                        if (kstatus != KERN_SUCCESS)
                        {
                                _asl_global_reset();
                                break;
                        }
                }

                if (res == NULL) break;

                batch = asl_list_from_string(res);
                vm_deallocate(mach_task_self(), (vm_address_t)res, reslen);

                status = _asl_search_concat_results(batch, &out);
                if (status != ASL_STATUS_OK) break;
                if ((out == NULL) || (out->count < FETCH_BATCH)) break;

                if (cmax >= qmin) qmin = cmax + 1;
        }

        free(str);

        return out;
}

aslmsg
_asl_server_control_query(void)
{
        asl_search_result_t *list = NULL;
        char *qstr, *res;
        uint32_t len, reslen, status;
        uint64_t cmax, qmin;
        kern_return_t kstatus;
        caddr_t vmstr;
        asl_msg_t *m = NULL;
        static const char ctlstr[] = "1\nQ [= ASLOption control]\n";

        _asl_global_init();
        if (_asl_global.server_port == MACH_PORT_NULL) return NULL;

        len = strlen(ctlstr) + 1;

        qmin = 0;
        cmax = 0;
        res = NULL;
        reslen = 0;

        kstatus = vm_allocate(mach_task_self(), (vm_address_t *)&vmstr, len, TRUE);
        if (kstatus != KERN_SUCCESS) return NULL;

        memmove(vmstr, ctlstr, len);

        status = 0;
        kstatus = _asl_server_query_2(_asl_global.server_port, vmstr, len, qmin, FETCH_BATCH, 0, (caddr_t *)&res, &reslen, &cmax, (int *)&status);
        if (kstatus != KERN_SUCCESS)
        {
                /* retry once if the call failed */
                _asl_global_reset();
                _asl_global_init();
                kstatus = _asl_server_query_2(_asl_global.server_port, vmstr, len, qmin, FETCH_BATCH, 0, (caddr_t *)&res, &reslen, &cmax, (int *)&status);
                if (kstatus != KERN_SUCCESS) _asl_global_reset();
        }
        
        list = asl_list_from_string(res);
        vm_deallocate(mach_task_self(), (vm_address_t)res, reslen);

        if (list == NULL) return NULL;
        if (list->count > 0) m = asl_msg_retain(list->msg[0]);
        aslresponse_free((aslresponse)list);
        return (aslmsg)m;
}

int
asl_store_location()
{
        kern_return_t kstatus;
        char *res;
        uint32_t reslen, status;
        uint64_t cmax;

        _asl_global_init();
        if (_asl_global.server_port == MACH_PORT_NULL) return ASL_STORE_LOCATION_FILE;

        res = NULL;
        reslen = 0;
        cmax = 0;
        status = ASL_STATUS_OK;

        kstatus = _asl_server_query_2(_asl_global.server_port, NULL, 0, 0, -1, 0, (caddr_t *)&res, &reslen, &cmax, (int *)&status);
        if (kstatus != KERN_SUCCESS)
        {
                /* retry once if the call failed */
                _asl_global_reset();
                _asl_global_init();
                kstatus = _asl_server_query_2(_asl_global.server_port, NULL, 0, 0, -1, 0, (caddr_t *)&res, &reslen, &cmax, (int *)&status);
        }

        /* res should never be returned, but just to be certain we don't leak VM ... */
        if (res != NULL) vm_deallocate(mach_task_self(), (vm_address_t)res, reslen);

        if (kstatus != KERN_SUCCESS)
        {
                _asl_global_reset();
                return ASL_STORE_LOCATION_FILE;
        }

        if (status == ASL_STATUS_OK) return ASL_STORE_LOCATION_MEMORY;
        return ASL_STORE_LOCATION_FILE;
}

aslresponse
asl_search(aslclient ac, aslmsg a)
{
        int where;
        asl_search_result_t *out;

        _asl_global_init();

        where = asl_store_location();
        if (where == ASL_STORE_LOCATION_FILE) out = _asl_search_store(ac, a);
        else out = _asl_search_memory(ac, a);

        return out;
}

int
asl_syslog_faciliy_name_to_num(const char *name)
{
        if (name == NULL) return -1;

        if (strcaseeq(name, "auth")) return LOG_AUTH;
        if (strcaseeq(name, "authpriv")) return LOG_AUTHPRIV;
        if (strcaseeq(name, "cron")) return LOG_CRON;
        if (strcaseeq(name, "daemon")) return LOG_DAEMON;
        if (strcaseeq(name, "ftp")) return LOG_FTP;
        if (strcaseeq(name, "install")) return LOG_INSTALL;
        if (strcaseeq(name, "kern")) return LOG_KERN;
        if (strcaseeq(name, "lpr")) return LOG_LPR;
        if (strcaseeq(name, "mail")) return LOG_MAIL;
        if (strcaseeq(name, "netinfo")) return LOG_NETINFO;
        if (strcaseeq(name, "remoteauth")) return LOG_REMOTEAUTH;
        if (strcaseeq(name, "news")) return LOG_NEWS;
        if (strcaseeq(name, "security")) return LOG_AUTH;
        if (strcaseeq(name, "syslog")) return LOG_SYSLOG;
        if (strcaseeq(name, "user")) return LOG_USER;
        if (strcaseeq(name, "uucp")) return LOG_UUCP;
        if (strcaseeq(name, "local0")) return LOG_LOCAL0;
        if (strcaseeq(name, "local1")) return LOG_LOCAL1;
        if (strcaseeq(name, "local2")) return LOG_LOCAL2;
        if (strcaseeq(name, "local3")) return LOG_LOCAL3;
        if (strcaseeq(name, "local4")) return LOG_LOCAL4;
        if (strcaseeq(name, "local5")) return LOG_LOCAL5;
        if (strcaseeq(name, "local6")) return LOG_LOCAL6;
        if (strcaseeq(name, "local7")) return LOG_LOCAL7;
        if (strcaseeq(name, "launchd")) return LOG_LAUNCHD;

        return -1;
}

const char *
asl_syslog_faciliy_num_to_name(int n)
{
        if (n < 0) return NULL;

        if (n == LOG_AUTH) return "auth";
        if (n == LOG_AUTHPRIV) return "authpriv";
        if (n == LOG_CRON) return "cron";
        if (n == LOG_DAEMON) return "daemon";
        if (n == LOG_FTP) return "ftp";
        if (n == LOG_INSTALL) return "install";
        if (n == LOG_KERN) return "kern";
        if (n == LOG_LPR) return "lpr";
        if (n == LOG_MAIL) return "mail";
        if (n == LOG_NETINFO) return "netinfo";
        if (n == LOG_REMOTEAUTH) return "remoteauth";
        if (n == LOG_NEWS) return "news";
        if (n == LOG_AUTH) return "security";
        if (n == LOG_SYSLOG) return "syslog";
        if (n == LOG_USER) return "user";
        if (n == LOG_UUCP) return "uucp";
        if (n == LOG_LOCAL0) return "local0";
        if (n == LOG_LOCAL1) return "local1";
        if (n == LOG_LOCAL2) return "local2";
        if (n == LOG_LOCAL3) return "local3";
        if (n == LOG_LOCAL4) return "local4";
        if (n == LOG_LOCAL5) return "local5";
        if (n == LOG_LOCAL6) return "local6";
        if (n == LOG_LOCAL7) return "local7";
        if (n == LOG_LAUNCHD) return "launchd";

        return NULL;
}

/*
 * utility for converting a time string into a time_t
 * we only deal with the following formats:
 * Canonical form YYYY.MM.DD hh:mm:ss UTC
 * ctime() form Mth dd hh:mm:ss (e.g. Aug 25 09:54:37)
 * absolute form - # seconds since the epoch (e.g. 1095789191)
 * relative time - seconds before or after now (e.g. -300, +43200)
 * relative time - days/hours/minutes/seconds before or after now (e.g. -1d, +6h, +30m, -10s)
 */

#define CANONICAL_TIME_REX "^[0-9][0-9][0-9][0-9].[01]?[0-9].[0-3]?[0-9][ ]+[0-2]?[0-9]:[0-5][0-9]:[0-5][0-9][ ]+UTC$"
#define CTIME_REX "^[adfjmnos][aceopu][bcglnprtvy][ ]+[0-3]?[0-9][ ]+[0-2]?[0-9]:[0-5][0-9]:[0-5][0-9]$"
#define ABSOLUTE_TIME_REX "^[0-9]+[s]?$"
#define RELATIVE_TIME_REX "^[\\+-\\][0-9]+[smhdw]?$"

#define SECONDS_PER_MINUTE 60
#define SECONDS_PER_HOUR 3600
#define SECONDS_PER_DAY 86400
#define SECONDS_PER_WEEK 604800

static regex_t rex_canon, rex_ctime, rex_abs, rex_rel;
static int reg_status = 0;

/*
 * We use the last letter in the month name to determine
 * the month number (0-11).  There are two collisions:
 * Jan and Jun both end in n
 * Mar and Apr both end in r
 * In these cases we check the second letter.
 *
 * The MTH_LAST array maps the last letter to a number.
 */
static const int8_t MTH_LAST[] = {-1, 1, 11, -1, -1, -1, 7, -1, -1, -1, -1, 6, -1, 5, -1, 8, -1, 3, -1, 9, -1, 10, -1, -1, 4, -1};

static int
_month_num(char *s)
{
        int i;
        int8_t v8;

        v8 = -1;
        if (s[2] > 90) v8 = s[2] - 'a';
        else v8 = s[2] - 'A';

        if ((v8 < 0) || (v8 > 25)) return -1;

        v8 = MTH_LAST[v8];
        if (v8 < 0) return -1;

        i = v8;
        if ((i == 5) && ((s[1] == 'a') || (s[1] == 'A'))) return 0;
        if ((i == 3) && ((s[1] == 'a') || (s[1] == 'A'))) return 2;
        return i;
}

time_t
asl_parse_time(const char *in)
{
        int len, y;
        struct tm t;
        time_t tick, delta, factor;
        char *str, *p, *x;
        static dispatch_once_t once;

        if (in == NULL) return -1;

        dispatch_once(&once, ^{
                int status;
                int rflags = REG_EXTENDED | REG_NOSUB | REG_ICASE;

                memset(&rex_canon, 0, sizeof(regex_t));
                status = regcomp(&rex_canon, CANONICAL_TIME_REX, rflags);
                if (status != 0) reg_status = -1;

                memset(&rex_ctime, 0, sizeof(regex_t));
                status = regcomp(&rex_ctime, CTIME_REX, rflags);
                if (status != 0) reg_status = -1;

                memset(&rex_abs, 0, sizeof(regex_t));
                status = regcomp(&rex_abs, ABSOLUTE_TIME_REX, rflags);
                if (status != 0) reg_status = -1;

                memset(&rex_rel, 0, sizeof(regex_t));
                status = regcomp(&rex_rel, RELATIVE_TIME_REX, rflags);
                if (status != 0) reg_status = -1;
        });

        if (reg_status < 0) return -1;

        len = strlen(in) + 1;

        if (regexec(&rex_abs, in, 0, NULL, 0) == 0)
        {
                /*
                 * Absolute time (number of seconds since the epoch)
                 */
                str = strdup(in);
                if (str == NULL) return -1;

                if ((str[len-2] == 's') || (str[len-2] == 'S')) str[len-2] = '\0';

                tick = atol(str);
                free(str);

                return tick;
        }
        else if (regexec(&rex_rel, in, 0, NULL, 0) == 0)
        {
                /*
                 * Reletive time (number of seconds before or after right now)
                 */
                str = strdup(in);
                if (str == NULL) return -1;

                factor = 1;

                if ((str[len-2] == 's') || (str[len-2] == 'S'))
                {
                        str[len-2] = '\0';
                }
                else if ((str[len-2] == 'm') || (str[len-2] == 'M'))
                {
                        str[len-2] = '\0';
                        factor = SECONDS_PER_MINUTE;
                }
                else if ((str[len-2] == 'h') || (str[len-2] == 'H'))
                {
                        str[len-2] = '\0';
                        factor = SECONDS_PER_HOUR;
                }
                else if ((str[len-2] == 'd') || (str[len-2] == 'D'))
                {
                        str[len-2] = '\0';
                        factor = SECONDS_PER_DAY;
                }
                else if ((str[len-2] == 'w') || (str[len-2] == 'W'))
                {
                        str[len-2] = '\0';
                        factor = SECONDS_PER_WEEK;
                }

                tick = time(NULL);
                delta = factor * atol(str);
                tick += delta;

                free(str);

                return tick;
        }
        else if (regexec(&rex_canon, in, 0, NULL, 0) == 0)
        {
                memset(&t, 0, sizeof(struct tm));
                str = strdup(in);
                if (str == NULL) return -1;

                /* Get year */
                x = str;
                p = strchr(x, '.');
                *p = '\0';
                t.tm_year = atoi(x) - 1900;

                /* Get month */
                x = p + 1;
                p = strchr(x, '.');
                *p = '\0';
                t.tm_mon = atoi(x) - 1;

                /* Get day */
                x = p + 1;
                p = strchr(x, ' ');
                *p = '\0';
                t.tm_mday = atoi(x);

                /* Get hour */
                for (x = p + 1; *x == ' '; x++);
                p = strchr(x, ':');
                *p = '\0';
                t.tm_hour = atoi(x);

                /* Get minutes */
                x = p + 1;
                p = strchr(x, ':');
                *p = '\0';
                t.tm_min = atoi(x);

                /* Get seconds */
                x = p + 1;
                p = strchr(x, ' ');
                *p = '\0';
                t.tm_sec = atoi(x);

                free(str);
                return timegm(&t);
        }
        else if (regexec(&rex_ctime, in, 0, NULL, 0) == 0)
        {
                /* We assume it's in the current year */
                memset(&t, 0, sizeof(struct tm));
                tick = time(NULL);
                gmtime_r(&tick, &t);
                y = t.tm_year;

                memset(&t, 0, sizeof(struct tm));
                str = strdup(in);
                if (str == NULL) return -1;

                t.tm_year = y;
                t.tm_mon = _month_num(str);
                if (t.tm_mon < 0) return -1;

                for (x = strchr(str, ' '); *x == ' '; x++);
                p = strchr(x, ' ');
                *p = '\0';
                t.tm_mday = atoi(x);

                /* Get hour */
                for (x = p + 1; *x == ' '; x++);
                p = strchr(x, ':');
                *p = '\0';
                t.tm_hour = atoi(x);

                /* Get minutes */
                x = p + 1;
                p = strchr(x, ':');
                *p = '\0';
                t.tm_min = atoi(x);

                /* Get seconds */
                x = p + 1;
                t.tm_sec = atoi(x);

                t.tm_isdst = -1;

                free(str);
                return mktime(&t);
        }

        return -1;
}

#endif /* BUILDING_VARIANT */