FullPulse/app/lib/m_management/vty.c

/******************************************************************************
 * file    lib/management/vty.c 
 * author  YuLiang
 * version 1.0.0
 * date    09-Oct-2021
 * brief   This file provides all the vty operation functions.
 *
 ******************************************************************************
 * Attention
 *
 * <h2><center>&copy; COPYRIGHT(c) 2021 LandPower</center></h2>
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *   1. Redistributions of source code must retain the above copyright notice,
 *      this list of conditions and the following disclaimer.
 *   2. Redistributions in binary form must reproduce the above copyright notice,
 *      this list of conditions and the following disclaimer in the documentation
 *      and/or other materials provided with the distribution.
 *   3. Neither the name of LandPower nor the names of its contributors may be used to 
 *      endorse or promote products derived from this software without specific
 *      prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 ******************************************************************************/

/* Includes ------------------------------------------------------------------*/
//#ifdef HAVE_CONFIG_H
#include "config.h"
//#endif

#include <stdarg.h>
#include <sys/types.h>
#include <sys/time.h>
#include <pthread.h>
#include <arpa/inet.h>
#include <arpa/telnet.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <sys/uio.h>
#include <assert.h>
#include <ctype.h>

#include "list.h"
#include "sockunion.h"
#include "vty.h"
#include "cmd.h"

/* Private define ------------------------------------------------------------*/
#define BUFFER_SIZE_DEFAULT 4096
#define BUF_MAX_CHUNKS 16
#define BUF_MAX_FLUSH 131072

/* Private macro -------------------------------------------------------------*/
#define BUFFER_DATA_FREE(D) XFREE(MTYPE_BUF_DATA, (D))

/* Private typedef -----------------------------------------------------------*/
typedef enum
{
    BUFFER_ERROR = -1,          /* I/O错误产生. */
    BUFFER_EMPTY = 0,           /* 数据发送成功, 并且没有其他数据要发送了. */
    BUFFER_PENDING = 1          /* 数据发送成功, 但是数据并没有发送完. */
} BUF_STATUS_E;

/* Private variables ---------------------------------------------------------*/
static hash_t *cpu_record = NULL;
static struct timeval last_recent_time;
static struct timeval relative_time_base;
struct timeval recent_time;
/* init flag */
static unsigned short timers_inited;
/* Relative time, since startup */
static struct timeval relative_time;

/* Configure lock. */
static int vty_config;

static const char vty_backward_char = 0x08;
static const char vty_space_char = ' ';

thread_master_t *vty_master;

/* Vector which store each vty structure. */
array_t *vtyvec;
/* VTY server thread. */
array_t *vty_serv_thread;
/* user array. */
array_t *vty_user;

/* Vty access-class command */
static char *vty_accesslist_name = NULL;
#ifdef HAVE_IPV6
/* Vty access-calss for IPv6. */
static char *vty_ipv6_accesslist_name = NULL;
#endif

/* Private function prototypes -----------------------------------------------*/

/* Internal functions --------------------------------------------------------*/
/* 在buf中添加一个data空间. */
static buf_data_t *_buf_add(buf_t *b)
{
    buf_data_t *d;

    d = XMALLOC(MTYPE_BUF_DATA, l_offsetof(buf_data_t, data[b->size]));
    d->cp = d->sp = 0;
    d->next = NULL;

    if (b->tail)
        b->tail->next = d;
    else
        b->head = d;
    b->tail = d;

    return d;
}

/* 创建buf. */
buf_t *buf_create(size_t size)
{
    buf_t *b = NULL;

    b = XMALLOC(MTYPE_BUF, sizeof(buf_t));

    if (size)
        b->size = size;
    else
    {
        static size_t default_size;
        if (!default_size)
        {
            long pgsz = sysconf(_SC_PAGESIZE);
            default_size = (((BUFFER_SIZE_DEFAULT-1)/pgsz+1)*pgsz);
        }
        b->size = default_size;
    }

    return b;
}

/* 释放所有buf中的空间. */
void buf_reset(buf_t *b)
{
    buf_data_t *data = NULL;
    buf_data_t *next = NULL;
  
    for (data = b->head; data; data = next)
    {
        next = data->next;
        BUFFER_DATA_FREE(data);
    }
    b->head = b->tail = NULL;
}

/* 释放buf_t结构,包括buf空间. */
void buf_free(buf_t *b)
{
    buf_reset(b);
    XFREE(MTYPE_BUF, b);
}

/* 将数据存入buf. */
void buf_put(buf_t *b, const void *p, size_t size)
{
    buf_data_t *data = b->tail;
    const char *ptr = p;

    /* We use even last one byte of data buffer. */
    while(size)    
    {
        size_t chunk = 0;

        /* If there is no data buffer add it. */
        if (NULL == data || data->cp == b->size)
            data = _buf_add(b);

        chunk = ((size <= (b->size - data->cp)) ? size : (b->size - data->cp));
        memcpy((data->data + data->cp), ptr, chunk);
        size -= chunk;
        ptr += chunk;
        data->cp += chunk;
    }
}

/* 设计用于非阻塞socket. 如果数据太大, 该接口并不会全部发送.
   返回0如果数据全部发送, 1表示还有数据没有发送完, -1表示发送
   产生了致命错误. */
BUF_STATUS_E buf_flush_available(buf_t *b, int32_t fd)
{
    buf_data_t *d = NULL;
    size_t written = 0;
    struct iovec iov[BUF_MAX_CHUNKS];
    size_t iovcnt = 0;
    size_t nbyte = 0;

    /* 将数据填入iov,最多使用BUF_MAX_CHUNKS个iov,并且不能超过
       BUF_MAX_FLUSH字节. */
    for(d = b->head, iovcnt = 0;
        d && (iovcnt < BUF_MAX_CHUNKS) && (nbyte < BUF_MAX_FLUSH);
        d = d->next, iovcnt++)
    {
        iov[iovcnt].iov_base = d->data + d->sp;
        nbyte += (iov[iovcnt].iov_len = d->cp - d->sp);
    }

    if (!nbyte)
        return BUFFER_EMPTY;

    /* 数据输出到终端. */
    if ((ssize_t)(written = writev(fd, iov, iovcnt)) < 0)
    {
        if (ERRNO_IO_RETRY(errno))
            return BUFFER_PENDING;
        
        printf("%s: write error on fd %d: %s.\n", __FUNCTION__, fd, safe_strerror(errno));
        return BUFFER_ERROR;
    }

    /* 释放被输出到终端的data. */
    while(written > 0)
    {
        if (!(d = b->head))
        {
            printf("%s: corruption detected: buffer queue empty, but written is %lu", __func__, (u_long)written);
            break;
        }

        if (written < (d->cp - d->sp))
        {
            d->sp += written;
            return BUFFER_PENDING;
        }

        written -= (d->cp-d->sp);
        if (!(b->head = d->next))
            b->tail = NULL;
        
        BUFFER_DATA_FREE(d);
    }

    return b->head ? BUFFER_PENDING : BUFFER_EMPTY;
}

/* 发送数据到终端,仅用于telnet接口 */
BUF_STATUS_E buf_flush_window(buf_t *b, int fd, int32_t width, int32_t height,
                              int32_t erase_flag, int32_t no_more_flag)
{
    int32_t nbytes = 0;
    int32_t iov_alloc = 0;
    int32_t iov_index = 0;
    struct iovec *iov = NULL;
    struct iovec small_iov[3];
    char more[] = " --More-- ";
    char erase[] = {0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
                      ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ',
                      0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08};
    buf_data_t *data = NULL;
    uint32_t column = 0;

    if (!b->head)
        return BUFFER_EMPTY;

    /* 获取显示的高度与宽度. */
    if (height < 1)
    {
        printf("%s called with non-positive window height %d, forcing to 1", __func__, height);
        height = 1;
    }
    else if (height >= 2)
        height--;

    if (width < 1)
    {
        printf("%s called with non-positive window width %d, forcing to 1", __func__, width);
        width = 1;
    }

    /* 计算发送一屏的数据要使用多少数据块. */
    if (NULL == b->head->next)
    {
        iov_alloc = sizeof(small_iov)/sizeof(small_iov[0]);
        iov = small_iov;
    }
    else
    {
        iov_alloc = ((height * (width + 2)) / b->size) + 10;
        iov = XMALLOC(MTYPE_BUF_TMP, iov_alloc * sizeof(*iov));
    }
    iov_index = 0;

    /* 处理清屏标志. */
    if (erase_flag)
    {
        iov[iov_index].iov_base = erase;
        iov[iov_index].iov_len = sizeof(erase);
        iov_index++;
    }

    /* 整理发送数据. */
    column = 1;  /* 下一个字符显示的列地址. */
    for (data = b->head; data && (height > 0); data = data->next)
    {
        size_t cp;

        /* 计算数据位置和行数,保证只显示height行(一屏)数据. */
        cp = data->sp;
        while ((cp < data->cp) && (height > 0))
        {
            if ('\r' == data->data[cp])
                column = 1;
            else if (('\n' == data->data[cp]) || (column == width))
            {
                column = 1;
                height--;
            }
            else
                column++;
            
            cp++;
        }
        iov[iov_index].iov_base = (char *)(data->data + data->sp);
        iov[iov_index++].iov_len = cp - data->sp;
        data->sp = cp;

        /* 以下情况应该不会发生,申请的块应该是足够发送数据的. */
        if (iov_index == iov_alloc)
        {
            iov_alloc *= 2;
            if (iov != small_iov)
            {
                printf("%s: growing iov array to %d;width %d, height %d, size %lu",
                       __func__, iov_alloc, width, height, (u_long)b->size);
                iov = XREALLOC(MTYPE_BUF_TMP, iov, iov_alloc * sizeof(*iov));
            }
            else
            {
                printf("%s: corruption detected: iov_small overflowed;head %p, tail %p, head->next %p",
                       __func__, b->head, b->tail, b->head->next);
                iov = XMALLOC(MTYPE_BUF_TMP, iov_alloc * sizeof(*iov));
                memcpy(iov, small_iov, sizeof(small_iov));
            }
        }
    }

    /* 显示" --More-- "提示. */
    if (b->tail && (b->tail->sp < b->tail->cp) && !no_more_flag)
    {
        iov[iov_index].iov_base = more;
        iov[iov_index].iov_len = sizeof(more);
        iov_index++;
    }

    /* 发送数据. */
    if ((nbytes = writev(fd, iov, iov_index)) < 0)
        printf("%s: writev to fd %d failed: %s", __func__, fd, safe_strerror(errno));

    /* 释放发送过的数据空间. */
    while (b->head && (b->head->sp == b->head->cp))
    {
        buf_data_t *del = NULL;

        if (!(b->head = (del = b->head)->next))
            b->tail = NULL;

        BUFFER_DATA_FREE(del);
    }

    if (iov != small_iov)
        XFREE(MTYPE_BUF_TMP, iov);

    return (nbytes < 0) ? BUFFER_ERROR : (b->head ? BUFFER_PENDING : BUFFER_EMPTY);
}

/* 持续发送数据, 直到数据发送完, 或者遇到错误,或者被拥塞. */
BUF_STATUS_E buf_flush_all(buf_t *b, int32_t fd)
{
    BUF_STATUS_E ret = BUFFER_ERROR;
    buf_data_t *head = NULL;
    size_t head_sp = 0;

    if (!b->head)
        return BUFFER_EMPTY;
    
    head_sp = (head = b->head)->sp;

    while(BUFFER_PENDING == (ret = buf_flush_available(b, fd)))
    {
        /* 数据不空, 但是没有发送出去,可能是内核buf满了. */
        if ((b->head == head) && (head_sp == head->sp) && (errno != EINTR))
            return ret;
        
        head_sp = (head = b->head)->sp;
    }

    return ret;
}

/* Lookup and return hash backet in hash. If there is no
 * corresponding hash backet and alloc_func is specified, create new
 * hash backet.  */
void *hash_get(hash_t *hash, void *data, hash_alloc_f alloc_func)
{
    unsigned int key = 0;
    unsigned int index = 0;
    void *newdata = 0;
    hash_backet_t *backet = NULL;

    key = (*hash->hash_key) (data);
    index = key % hash->size;

    for(backet = hash->index[index]; backet != NULL; backet = backet->next) 
    if (backet->key == key && (*hash->hash_cmp) (backet->data, data))
        return backet->data;

    if (alloc_func)
    {
        newdata = (*alloc_func)(data);
        if (NULL == newdata)
            return NULL;

        backet = XMALLOC(MTYPE_HASH_BACKET, sizeof(hash_backet_t));
        backet->data = newdata;
        backet->key = key;
        backet->next = hash->index[index];
        hash->index[index] = backet;
        hash->count++;
        return backet->data;
    }

    return NULL;
}

/* gettimeofday wrapper, to keep recent_time updated */
static int _thread_gettimeofday(struct timeval *tv)
{
    int ret = 0;
  
    assert(tv);
  
    if (!(ret = gettimeofday(&recent_time, NULL)))
    {
        /* init... */
        if (!timers_inited)
        {
            relative_time_base = last_recent_time = recent_time;
            timers_inited = 1;
        }
        /* avoid copy if user passed recent_time pointer.. */
        if (tv != &recent_time)
            *tv = recent_time;
        return 0;
    }
    
    return ret;
}

static int _thread_get_relative(struct timeval *tv)
{
    int ret = 0;
    struct timespec tp;

    if (!(ret = clock_gettime(CLOCK_MONOTONIC, &tp)))
    {
        relative_time.tv_sec = tp.tv_sec;
        relative_time.tv_usec = tp.tv_nsec / 1000;
    }

    if (tv)
        *tv = relative_time;

    return ret;
}
/* Adjust so that tv_usec is in the range [0,TIMER_SECOND_MICRO).
   And change negative values to 0. */
static struct timeval _thread_timeval_adjust (struct timeval a)
{
    while(a.tv_usec >= TIMER_SECOND_MICRO)
    {
        a.tv_usec -= TIMER_SECOND_MICRO;
        a.tv_sec++;
    }

    while(a.tv_usec < 0)
    {
        a.tv_usec += TIMER_SECOND_MICRO;
        a.tv_sec--;
    }

    if (a.tv_sec < 0)
        /* Change negative timeouts to 0. */
        a.tv_sec = a.tv_usec = 0;

    return a;
}

static unsigned long _thread_timeval_elapsed(struct timeval a, struct timeval b)
{
    return ((a.tv_sec - b.tv_sec) * TIMER_SECOND_MICRO) +
        (a.tv_usec - b.tv_usec);
}

/* Allocate a new hash.  */
hash_t *_thread_hash_create_size(hash_key_f *hash_key,
                         hash_cmp_f *hash_cmp,
                         unsigned int size)
{
    hash_t *hash;

    hash = XMALLOC(MTYPE_HASH, sizeof(hash_t));
    hash->index = XMALLOC(MTYPE_HASH_INDEX, sizeof(hash_backet_t *) * size);
    hash->size = size;
    hash->hash_key = hash_key;
    hash->hash_cmp = hash_cmp;
    hash->count = 0;

    return hash;
}

/* Add a new thread to the list.  */
static void _thread_list_enqueue(thread_list_t *list, thread_t *thread)
{
    thread->next = NULL;
    thread->prev = list->tail;
    if (list->tail)
        list->tail->next = thread;
    else
        list->head = thread;
    
    list->tail = thread;
    list->count++;
}

/* Delete a thread from the list. */
static thread_t *_thread_list_dequeue(thread_list_t *list, thread_t *thread)
{
    if (thread->next)
        thread->next->prev = thread->prev;
    else
        list->tail = thread->prev;
    
    if (thread->prev)
        thread->prev->next = thread->next;
    else
        list->head = thread->next;

    thread->next = thread->prev = NULL;
    list->count--;

    return thread;
}

/* Thread list is empty or not.  */
static inline int _thread_empty(thread_list_t *list)
{
    return list->head ? 0 : 1;
}

static long _thread_timeval_cmp(struct timeval a, struct timeval b)
{
    return a.tv_sec == b.tv_sec ?
        a.tv_usec - b.tv_usec : a.tv_sec - b.tv_sec;
}

/* Delete top of the list and return it. */
static thread_t *_thread_list_pull(thread_list_t *list)
{
    if (!_thread_empty(list))
        return _thread_list_dequeue(list, list->head);

    return NULL;
}

/* Add a new thread to the list.  */
static void _thread_list_add(thread_list_t *list,
                             thread_t *thread)
{
    thread->next = NULL;
    thread->prev = list->tail;
    
    if (list->tail)
        list->tail->next = thread;
    else
        list->head = thread;
    
    list->tail = thread;
    list->count++;
}

/* Add a new thread just before the point.  */
static void _thread_list_add_before(thread_list_t *list, 
                                    thread_t *point, 
                                    thread_t *thread)
{
    thread->next = point;
    thread->prev = point->prev;
    if (point->prev)
        point->prev->next = thread;
    else
        list->head = thread;

    point->prev = thread;
    list->count++;
}

/* Return remain time in second. */
unsigned long _thread_timer_remain_second(thread_t *thread)
{
    _thread_get_relative(NULL);

    if (thread->u.sands.tv_sec - relative_time.tv_sec > 0)
        return thread->u.sands.tv_sec - relative_time.tv_sec;
    else
        return 0;
}

/* Trim blankspace and "()"s */
static char *_thread_strip_funcname(const char *funcname) 
{
    char buff[100] = {0};
    char tmp = 0;
    char *ret = NULL;
    char *e = NULL;
    char *b = buff;

    strncpy(buff, funcname, sizeof(buff));
    buff[sizeof(buff) -1] = '\0';
    e = buff + strlen(buff) - 1;

    /* Wont work for funcname ==  "Word (explanation)"  */
    while (*b == ' ' || *b == '(')
        ++b;
    while (*e == ' ' || *e == ')')
        --e;
    e++;

    tmp = *e;
    *e = '\0';
    ret  = XSTRDUP(MTYPE_THREAD_FUNCNAME, b);
    *e = tmp;

    return ret;
}

/* Get new thread.  */
static thread_t *_thread_get(thread_master_t *m,
                             u_char type,
                             thread_func_f *func,
                             void *arg,
                             const char* funcname)
{
    thread_t *thread = NULL;

    if (!_thread_empty(&m->unuse))
    {
        thread = _thread_list_pull(&m->unuse);
        if (thread->funcname)
            XFREE(MTYPE_THREAD_FUNCNAME, thread->funcname);
    }
    else
    {
        thread = XMALLOC(MTYPE_THREAD, sizeof(thread_t));
        m->alloc++;
    }

    thread->type = type;
    thread->add_type = type;
    thread->master = m;
    thread->func = func;
    thread->arg = arg;
    thread->funcname = _thread_strip_funcname(funcname);

    return thread;
}

static void *_thread_cpu_record_hash_alloc(cpu_thread_history_t *a)
{
    cpu_thread_history_t *history = NULL;
    history = XMALLOC(MTYPE_THREAD_STATS, sizeof(cpu_thread_history_t));
    history->func = a->func;
    history->funcname = XSTRDUP(MTYPE_THREAD_FUNCNAME, a->funcname);
    return history;
}

/* Move thread to unuse list. */
static void _thread_add_unuse(thread_master_t *m, thread_t *thread)
{
    assert(m != NULL && thread != NULL);
    assert(NULL == thread->next);
    assert(NULL == thread->prev);
    assert(THREAD_UNUSED == thread->type);
    
    _thread_list_add(&m->unuse, thread);
    /* XXX: Should we deallocate funcname here? */
}

static unsigned int _thread_cpu_record_hash_key(cpu_thread_history_t *a)
{
    return (uintptr_t)a->func;
}

static int _thread_cpu_record_hash_cmp (const cpu_thread_history_t *a,
                                const cpu_thread_history_t *b)
{
    return a->func == b->func;
}

static thread_t *_thread_run(thread_master_t *m, thread_t *thread, thread_t *fetch)
{
    *fetch = *thread;
    thread->type = THREAD_UNUSED;
    thread->funcname = NULL;  /* thread_call will free fetch's copied pointer */
    _thread_add_unuse(m, thread);
    return fetch;
}

/* process a list en masse, e.g. for event thread lists */
static unsigned int _thread_process(thread_list_t *list)
{
    thread_t *thread = NULL;
    unsigned int ready = 0;
  
    for(thread = list->head; thread; thread = thread->next)
    {
        _thread_list_dequeue(list, thread);
        thread->type = THREAD_READY;
        _thread_list_add(&thread->master->ready, thread);
        ready++;
    }

    return ready;
}

static struct timeval _timeval_subtract(struct timeval a, struct timeval b)
{
    struct timeval ret;

    ret.tv_usec = a.tv_usec - b.tv_usec;
    ret.tv_sec = a.tv_sec - b.tv_sec;

    return _thread_timeval_adjust(ret);
}

static struct timeval *_thread_timer_wait(thread_list_t *tlist, struct timeval *timer_val)
{
    if (!_thread_empty (tlist))
    {
        *timer_val = _timeval_subtract(tlist->head->u.sands, relative_time);
        return timer_val;
    }

    return NULL;
}

/* Add all timers that have popped to the ready list. */
static uint32_t _thread_timer_process(thread_list_t *list, struct timeval *timenow)
{
    thread_t *thread = NULL;
    uint32_t ready = 0;
  
    for (thread = list->head; thread; thread = thread->next)
    {
        if (_thread_timeval_cmp(*timenow, thread->u.sands) < 0)
            return ready;
        
        _thread_list_dequeue(list, thread);
        thread->type = THREAD_READY;
        _thread_list_add(&thread->master->ready, thread);
        ready++;
    }
    
    return ready;
}

static int32_t _thread_process_fd(thread_list_t *list, fd_set *fdset, fd_set *mfdset)
{
    thread_t *thread = NULL;
    thread_t *next = NULL;
    int ready = 0;
  
    assert(list);
  
    for (thread = list->head; thread; thread = next)
    {
        next = thread->next;

        if (FD_ISSET(THREAD_FD(thread), fdset))
        {
            assert(FD_ISSET(THREAD_FD(thread), mfdset));
            FD_CLR(THREAD_FD (thread), mfdset);
            _thread_list_dequeue(list, thread);
            _thread_list_add(&thread->master->ready, thread);
            thread->type = THREAD_READY;
            ready++;
        }
    }

    return ready;
}

void thread_getrusage(RUSAGE_T *r)
{
    _thread_get_relative(NULL);
    getrusage(RUSAGE_SELF, &(r->cpu));
    r->real = relative_time;

    /* quagga_get_relative() only updates recent_time if gettimeofday
     * based, not when using CLOCK_MONOTONIC. As we export recent_time
     * and guarantee to update it before threads are run...*/
    _thread_gettimeofday(&recent_time);
}

/* We check thread consumed time. If the system has getrusage, we'll
use that to get in-depth stats on the performance of the thread in addition
to wall clock time stats from gettimeofday. */
void thread_call(thread_t *thread)
{
    unsigned long realtime = 0;
    unsigned long cputime = 0;
    RUSAGE_T ru;

    /* Cache a pointer to the relevant cpu history thread, if the thread
     * does not have it yet.
     *
     * Callers submitting 'dummy threads' hence must take care that
     * thread->cpu is NULL */
    if (!thread->hist)
    {
        cpu_thread_history_t tmp;

        tmp.func = (int (*)(void*))thread->func;
        tmp.funcname = thread->funcname;

        thread->hist = hash_get(cpu_record,
                                &tmp,
                                (hash_alloc_f *)_thread_cpu_record_hash_alloc);
    }

    GETRUSAGE(&thread->ru);

    (*thread->func)(thread);

    GETRUSAGE(&ru);

    realtime = thread_consumed_time(&ru, &thread->ru, &cputime);
    thread->hist->real.total += realtime;
    
    if (thread->hist->real.max < realtime)
        thread->hist->real.max = realtime;
    
    thread->hist->cpu.total += cputime;

    if (thread->hist->cpu.max < cputime)
        thread->hist->cpu.max = cputime;

    ++(thread->hist->total_calls);
    thread->hist->types |= (1 << thread->add_type);

    if (realtime > TIMER_SECOND_MICRO * 2)
    {
        /* We have a CPU Hog on our hands.
         * Whinge about it now, so we're aware this is yet another task
         * to fix. */
        printf("SLOW THREAD: task %s (%lx) ran for %lums (cpu time %lums)",
            thread->funcname,
            (unsigned long) thread->func,
            realtime/1000, cputime/1000);
    }

    XFREE(MTYPE_THREAD_FUNCNAME, thread->funcname);
}

/* Add new read thread. */
thread_t *thread_add_read(thread_master_t *m,
                          thread_func_f *func,
                          void *arg,
                          int fd,
                          const char* funcname)
{
    thread_t *thread = NULL;

    assert(m != NULL);

    if (FD_ISSET(fd, &m->readfd))
    {
        printf("There is already read fd [%d].\n", fd);
        return NULL;
    }

    thread = _thread_get(m, THREAD_READ, func, arg, funcname);
    FD_SET(fd, &m->readfd);
    thread->u.fd = fd;
    _thread_list_enqueue(&m->read, thread);

    return thread;
}

/* Add new write thread. */
thread_t *thread_add_write(thread_master_t *m,
                           thread_func_f *func,
                           void *arg,
                           int fd,
                           const char* funcname)
{
    thread_t *thread = NULL;

    assert(m != NULL);

    if (FD_ISSET(fd, &m->writefd))
    {
        printf("There is already write fd [%d]", fd);
        return NULL;
    }

    thread = _thread_get(m, THREAD_WRITE, func, arg, funcname);
    FD_SET(fd, &m->writefd);
    thread->u.fd = fd;
    _thread_list_add(&m->write, thread);

    return thread;
}

static thread_t *
thread_add_timer_timeval(thread_master_t *m,
                         thread_func_f *func, 
                         int type,
                         void *arg, 
                         struct timeval *time_relative, 
                         const char* funcname)
{
    thread_t *thread = NULL;
    thread_list_t *list = NULL;
    struct timeval alarm_time;
    thread_t *tt = NULL;

    assert(m != NULL);
    assert(type == THREAD_TIMER || type == THREAD_BACKGROUND);
    assert(time_relative);

    list = (type == THREAD_TIMER) ? &m->timer : &m->background;
    thread = _thread_get(m, type, func, arg, funcname);

    /* Do we need jitter here? */
    _thread_get_relative(NULL);
    alarm_time.tv_sec = relative_time.tv_sec + time_relative->tv_sec;
    alarm_time.tv_usec = relative_time.tv_usec + time_relative->tv_usec;
    thread->u.sands = _thread_timeval_adjust(alarm_time);

    /* Sort by timeval. */
    for(tt = list->head; tt; tt = tt->next)
        if (_thread_timeval_cmp(thread->u.sands, tt->u.sands) <= 0)
            break;

    if (tt)
        _thread_list_add_before(list, tt, thread);
    else
        _thread_list_add(list, thread);

    return thread;
}


/* Add timer event thread. */
thread_t *thread_add_timer(thread_master_t *m,
                           thread_func_f *func, 
                           void *arg,
                           long timer,
                           const char* funcname)
{
    struct timeval trel;

    assert(m != NULL);

    trel.tv_sec = timer;
    trel.tv_usec = 0;

    return thread_add_timer_timeval(m, func, THREAD_TIMER, arg,
                                         &trel, funcname);
}

/* Add timer event thread with "millisecond" resolution */
thread_t *thread_add_timer_msec(thread_master_t *m,
                                thread_func_f *func, 
                                void *arg,
                                long timer,
                                const char* funcname)
{
    struct timeval trel;

    assert(m != NULL);

    trel.tv_sec = timer / 1000;
    trel.tv_usec = 1000*(timer % 1000);

    return thread_add_timer_timeval(m, func, THREAD_TIMER, 
                                         arg, &trel, funcname);
}

/* Add a background thread, with an optional millisec delay */
thread_t *thread_add_background(thread_master_t *m,
                                thread_func_f *func,
                                void *arg, long delay, 
                                const char *funcname)
{
    struct timeval trel;

    assert(m != NULL);

    if (delay)
    {
        trel.tv_sec = delay / 1000;
        trel.tv_usec = 1000 * (delay % 1000);
    }
    else
    {
        trel.tv_sec = 0;
        trel.tv_usec = 0;
    }

    return thread_add_timer_timeval(m, func, THREAD_BACKGROUND,
                                         arg, &trel, funcname);
}

/* Add simple event thread. */
thread_t *thread_add_event(thread_master_t *m,
                           thread_func_f *func,
                           void *arg,
                           int val,
                           const char* funcname)
{
    thread_t *thread = NULL;

    assert(m != NULL);

    thread = _thread_get(m, THREAD_EVENT, func, arg, funcname);
    thread->u.val = val;
    _thread_list_add(&m->event, thread);

    return thread;
}

/* Execute thread */
thread_t *thread_execute(thread_master_t *m,
                         thread_func_f *func, 
                         void *arg,
                         int val,
                         const char* funcname)
{
    thread_t dummy; 

    memset(&dummy, 0, sizeof(thread_t));

    dummy.type = THREAD_EVENT;
    dummy.add_type = THREAD_PERFORM;
    dummy.master = NULL;
    dummy.func = func;
    dummy.arg = arg;
    dummy.u.val = val;
    dummy.funcname = _thread_strip_funcname(funcname);
    thread_call(&dummy);

    return NULL;
}

/* Allocate new thread master.  */
thread_master_t *thread_master_create()
{
    if (cpu_record == NULL)
        cpu_record 
        = _thread_hash_create_size((hash_key_f*)_thread_cpu_record_hash_key,
                           (hash_cmp_f*)_thread_cpu_record_hash_cmp,
                           1011);
    
    return (thread_master_t*)XMALLOC(MTYPE_THREAD_MASTER, sizeof(thread_master_t));
}

unsigned long thread_consumed_time(RUSAGE_T *now,
                                   RUSAGE_T *start,
                                   unsigned long *cputime)
{
    /* This is 'user + sys' time.  */
    *cputime = _thread_timeval_elapsed(now->cpu.ru_utime, start->cpu.ru_utime) +
        _thread_timeval_elapsed(now->cpu.ru_stime, start->cpu.ru_stime);

    return _thread_timeval_elapsed(now->real, start->real);
}

/* Cancel thread from scheduler. */
void thread_cancel(thread_t *thread)
{
    thread_list_t *list = NULL;

    switch(thread->type)
    {
    case THREAD_READ:
        assert(FD_ISSET(thread->u.fd, &thread->master->readfd));
        FD_CLR(thread->u.fd, &thread->master->readfd);
        list = &thread->master->read;
        break;
    case THREAD_WRITE:
        assert(FD_ISSET (thread->u.fd, &thread->master->writefd));
        FD_CLR(thread->u.fd, &thread->master->writefd);
        list = &thread->master->write;
        break;
    case THREAD_TIMER:
        list = &thread->master->timer;
        break;
    case THREAD_EVENT:
        list = &thread->master->event;
        break;
    case THREAD_READY:
        list = &thread->master->ready;
        break;
    case THREAD_BACKGROUND:
        list = &thread->master->background;
        break;
    default:
        return;
    }

    _thread_list_dequeue(list, thread);
    thread->type = THREAD_UNUSED;
    _thread_add_unuse(thread->master, thread);
}

/* Fetch next ready thread. */
thread_t *thread_fetch(thread_master_t *m, thread_t *fetch)
{
    thread_t *thread = NULL;
    fd_set readfd;
    fd_set writefd;
    fd_set exceptfd;
    struct timeval timer_val = {.tv_sec = 0, .tv_usec = 0};
    struct timeval timer_val_bg;
    struct timeval *timer_wait = &timer_val;
    struct timeval *timer_wait_bg = NULL;

    while (1)
    {
        int32_t num = 0;

        /* Drain the ready queue of already scheduled jobs, before scheduling
         * more. */
        if ((thread = _thread_list_pull(&m->ready)) != NULL)
            return _thread_run(m, thread, fetch);
      
        /* To be fair to all kinds of threads, and avoid starvation, we
         * need to be careful to consider all thread types for scheduling
         * in each quanta. I.e. we should not return early from here on. */
       
        /* Normal event are the next highest priority.  */
        _thread_process(&m->event);
      
        /* Structure copy.  */
        readfd = m->readfd;
        writefd = m->writefd;
        exceptfd = m->exceptfd;
      
        /* Calculate select wait timer if nothing else to do */
        if (0 == m->ready.count)
        {
            _thread_get_relative(NULL);
            timer_wait = _thread_timer_wait(&m->timer, &timer_val);
            timer_wait_bg = _thread_timer_wait(&m->background, &timer_val_bg);
          
            if (timer_wait_bg &&
                (!timer_wait || (_thread_timeval_cmp(*timer_wait, *timer_wait_bg) > 0)))
                timer_wait = timer_wait_bg;
        }

        /* 当可用的进程全为0时,不能让timer_wait为NULL,要不让该线程将永远停在select()处. */
        if (!timer_wait)
        {
            timer_val.tv_sec = 2;
            timer_val.tv_usec = 0;
            timer_wait = &timer_val;
        }
        
        num = select(FD_SETSIZE, &readfd, &writefd, &exceptfd, timer_wait);
        /* Signals should get quick treatment */
        if (num < 0)
        {
            if (EINTR == errno)
                continue; /* signal received - process it */

            printf("select() error: %s\n", safe_strerror(errno));
            return NULL;
        }

        /* Check foreground timers.  Historically, they have had higher
         * priority than I/O threads, so let's push them onto the ready
         * list in front of the I/O threads. */
        _thread_get_relative(NULL);
        _thread_timer_process(&m->timer, &relative_time);
      
        /* Got IO, process it */
        if (num > 0)
        {
            /* Normal priority read thead. */
            _thread_process_fd(&m->read, &readfd, &m->readfd);
            /* Write thead. */
            _thread_process_fd(&m->write, &writefd, &m->writefd);
        }

#if 0
        /* If any threads were made ready above (I/O or foreground timer),
         * perhaps we should avoid adding background timers to the ready
         * list at this time.  If this is code is uncommented, then background
         * timer threads will not run unless there is nothing else to do. */
        if ((thread = thread_trim_head (&m->ready)) != NULL)
            return thread_run (m, thread, fetch);
#endif

        /* Background timer/events, lowest priority */
        _thread_timer_process(&m->background, &relative_time);
      
        if ((thread = _thread_list_pull(&m->ready)) != NULL)
            return _thread_run(m, thread, fetch);
    }
}

/* Get telnet window size. */
static int _vty_telnet_option(vty_t *vty, unsigned char *buf, int nbytes)
{
    switch (buf[0])
    {
    case SB:
        vty->sb_len = 0;
        vty->iac_sb_in_progress = 1;
        return 0;
        break;
    case SE: 
    {
        if (!vty->iac_sb_in_progress)
            return 0;

        if ((vty->sb_len == 0) || (vty->sb_buf[0] == '\0'))
        {
            vty->iac_sb_in_progress = 0;
            return 0;
        }
        switch (vty->sb_buf[0])
        {
        case TELOPT_NAWS:
            if (vty->sb_len != TELNET_NAWS_SB_LEN)
                printf("RFC 1073 violation detected: telnet NAWS option\
                    should send %d characters, but we received %lu.\n",
                    TELNET_NAWS_SB_LEN, (u_long)vty->sb_len);
            else if (sizeof(vty->sb_buf) < TELNET_NAWS_SB_LEN)
                printf("Bug detected: sizeof(vty->sb_buf) %lu < %d, \
                    too small to handle the telnet NAWS option.\n",
                    (u_long)sizeof(vty->sb_buf), TELNET_NAWS_SB_LEN);
            else
            {
                vty->width = ((vty->sb_buf[1] << 8)|vty->sb_buf[2]);
                vty->height = ((vty->sb_buf[3] << 8)|vty->sb_buf[4]);
            }
            break;
        }

        vty->iac_sb_in_progress = 0;
        return 0;
        break;
    }
    default:
        break;
    }
    
    return 1;
}

/* Basic function to write buffer to vty. */
static void _vty_write(vty_t *vty, const char *buf, size_t nbytes)
{
    /* Should we do buffering here ?  And make vty_flush (vty) ? */
    buf_put(vty->out_buf, buf, nbytes);
}

/* This function redraw all of the command line character. */
static void _vty_redraw_line(vty_t *vty)
{
    _vty_write(vty, vty->buf, vty->length);
    vty->cp = vty->length;
}

/* Quit print out to the buffer. */
static void _vty_buffer_reset(vty_t *vty)
{
    buf_reset(vty->out_buf);
    vty_prompt(vty);
    _vty_redraw_line(vty);
}

/* Backward character. */
static void _vty_backward_char(vty_t *vty)
{
    if (vty->cp > 0)
    {
        vty->cp--;
        _vty_write(vty, &vty_backward_char, 1);
    }
}

/* Forward character. */
static void _vty_forward_char(vty_t *vty)
{
    if (vty->cp < vty->length)
    {
        _vty_write(vty, &vty->buf[vty->cp], 1);
        vty->cp++;
    }
}

/* Move to the beginning of the line. */
static void _vty_beginning_of_line(vty_t *vty)
{
    while (vty->cp)
        _vty_backward_char(vty);
}

/* Move to the end of the line. */
static void _vty_end_of_line(vty_t *vty)
{
    while(vty->cp < vty->length)
        _vty_forward_char(vty);
}

/* Kill rest of line from current point. */
static void _vty_kill_line(vty_t *vty)
{
    unsigned int i = 0;
    unsigned int size = 0;

    size = vty->length - vty->cp;
  
    if (0 == size)
        return;

    for (i = 0; i < size; i++)
        _vty_write(vty, &vty_space_char, 1);
    for (i = 0; i < size; i++)
        _vty_write(vty, &vty_backward_char, 1);

    memset(&vty->buf[vty->cp], 0, size);
    vty->length = vty->cp;
}

/* Kill line from the beginning. */
static void _vty_kill_line_from_beginning(vty_t *vty)
{
    _vty_beginning_of_line(vty);
    _vty_kill_line(vty);
}

/* Print command line history.  This function is called from
   vty_next_line and vty_previous_line. */
static void _vty_history_print(vty_t *vty)
{
    unsigned int length = 0;

    _vty_kill_line_from_beginning (vty);

    /* Get previous line from history buffer */
    length = strlen(vty->hist[vty->hp]);
    memcpy(vty->buf, vty->hist[vty->hp], length);
    vty->cp = vty->length = length;

    /* Redraw current line */
    _vty_redraw_line(vty);
}

/* Show previous command line history. */
static void _vty_previous_line(vty_t *vty)
{
    unsigned int try_index = 0;

    try_index = vty->hp;
    if (try_index == 0)
        try_index = VTY_MAXHIST - 1;
    else
        try_index--;

    if (vty->hist[try_index] == NULL)
        return;
    else
        vty->hp = try_index;

    _vty_history_print(vty);
}

/* Show next command line history. */
static void _vty_next_line(vty_t *vty)
{
    unsigned int try_index = 0;

    if (vty->hp == vty->hindex)
        return;

    /* Try is there history exist or not. */
    try_index = vty->hp;
    if (try_index == (VTY_MAXHIST - 1))
        try_index = 0;
    else
        try_index++;

    /* If there is not history return. */
    if (vty->hist[try_index] == NULL)
        return;
    else
        vty->hp = try_index;

    _vty_history_print (vty);
}

/* Escape character command map. */
static void _vty_escape_map (unsigned char c, vty_t *vty)
{
    switch (c)
    {
    case ('A'):
        _vty_previous_line (vty);
        break;
    case ('B'):
        _vty_next_line(vty);
        break;
    case ('C'):
        _vty_forward_char(vty);
        break;
    case ('D'):
        _vty_backward_char (vty);
        break;
    default:
        break;
    }

    /* Go back to normal mode. */
    vty->escape = VTY_NO_ESCAPE;
}

/* Backward word. */
static void _vty_backward_word(vty_t *vty)
{
    while(vty->cp > 0 && vty->buf[vty->cp - 1] == ' ')
        _vty_backward_char(vty);

    while(vty->cp > 0 && vty->buf[vty->cp - 1] != ' ')
        _vty_backward_char(vty);
}

/* Forward word. */
static void _vty_forward_word(vty_t *vty)
{
    while (vty->cp != vty->length && vty->buf[vty->cp] != ' ')
        _vty_forward_char(vty);
  
    while (vty->cp != vty->length && vty->buf[vty->cp] == ' ')
        _vty_forward_char(vty);
}

/* Delete a charcter at the current point. */
static void _vty_delete_char(vty_t *vty)
{
    unsigned int i = 0;
    unsigned int size = 0;

    if (vty->length == 0)
        return;

    if (vty->cp == vty->length)
        return;

    size = vty->length - vty->cp;

    vty->length--;
    memmove(&vty->buf[vty->cp], &vty->buf[vty->cp + 1], size - 1);
    vty->buf[vty->length] = '\0';

    _vty_write(vty, &vty->buf[vty->cp], size - 1);
    _vty_write(vty, &vty_space_char, 1);

    for (i = 0; i < size; i++)
        _vty_write(vty, &vty_backward_char, 1);
}

/* Delete a character before the point. */
static void _vty_delete_backward_char(vty_t *vty)
{
    if (vty->cp == 0)
        return;

    _vty_backward_char(vty);
    _vty_delete_char(vty);
}

/* Delete a word before the point. */
static void _vty_forward_kill_word(vty_t *vty)
{
    while(vty->cp != vty->length && vty->buf[vty->cp] == ' ')
        _vty_delete_char(vty);
    while(vty->cp != vty->length && vty->buf[vty->cp] != ' ')
        _vty_delete_char(vty);
}

/* Delete a word before the point. */
static void _vty_backward_kill_word(vty_t *vty)
{
    while(vty->cp > 0 && vty->buf[vty->cp - 1] == ' ')
        _vty_delete_backward_char(vty);
    while(vty->cp > 0 && vty->buf[vty->cp - 1] != ' ')
        _vty_delete_backward_char(vty);
}

/* Ensure length of input buffer.  Is buffer is short, double it. */
static void _vty_buf_len_ensure(vty_t *vty, int length)
{
    if (vty->max <= length)
    {
        vty->max *= 2;
        vty->buf = XREALLOC(MTYPE_VTY, vty->buf, vty->max);
    }
}

/* Basic function to insert character into vty. */
static void _vty_insert_char(vty_t *vty, char c)
{
    unsigned int i = 0;
    unsigned int length = 0;

    _vty_buf_len_ensure(vty, vty->length + 1);
    length = vty->length - vty->cp;
    memmove(&vty->buf[vty->cp + 1], &vty->buf[vty->cp], length);
    vty->buf[vty->cp] = c;

    if (vty->node != PASSWORD_NODE)
    {
        _vty_write(vty, &vty->buf[vty->cp], length + 1);
        for (i = 0; i < length; i++)
            _vty_write(vty, &vty_backward_char, 1);
    }

    vty->cp++;
    vty->length++;
}

/* Insert a word into vty interface with overwrite mode. */
static void _vty_insert_word(vty_t *vty, char *str)
{
    int len = strlen(str);
    _vty_write(vty, str, len);
    strcpy(&vty->buf[vty->cp], str);
    vty->cp += len;
    vty->length = vty->cp;
}

void _vty_describe_command(vty_t *vty)
{
    array_t *cmd_line = NULL;

    cmd_line = cmd_strs_create(vty->buf);
    /* In case of '> ?'. */
    if (NULL == cmd_line)
    {
        cmd_line = array_init(1, MTYPE_CLI);
        array_append(cmd_line, '\0', MTYPE_CLI);
    }
    else if(vty->length && isspace((int)vty->buf[vty->length - 1]))
        array_append(cmd_line, '\0', MTYPE_CLI);

    vty_question(vty, cmd_line);

    cmd_strs_free(cmd_line);
    vty_prompt(vty);
    _vty_redraw_line(vty);
    return;
}

static void _vty_append_word(vty_t *vty, array_t *cmd_line, char *word, int status)
{
     unsigned int index = array_active(cmd_line) - 1;

    _vty_end_of_line(vty);

    if (NULL == array_get(cmd_line, index))
        _vty_insert_word(vty, word);
    else
    {
        _vty_backward_word(vty);
        _vty_insert_word(vty, word);
    }

    if (CMD_COMPLETE_FULL_MATCH == status)
        _vty_insert_char(vty, ' ');
}

int _vty_complete_command(vty_t *vty)
{
    array_t *cmd_line = NULL;
    char **match_strs = NULL;
    int32_t complete_status = CMD_ERR_NO_MATCH;

    cmd_line = cmd_strs_create(vty->buf);
    if (NULL == cmd_line)
    {
        cmd_line = array_init(1, MTYPE_CLI);
        array_append(cmd_line, '\0', MTYPE_CLI);
    }
    else if (vty->length && isspace((int)vty->buf[vty->length - 1]))
        array_append(cmd_line, '\0', MTYPE_CLI);

    match_strs = cmd_complete_command(cmd_line, vty, &complete_status);
    if (NULL == match_strs)
    {
        cmd_strs_free(cmd_line);
        return 0;
    }

    if (CMD_COMPLETE_MATCH == complete_status ||
        CMD_COMPLETE_FULL_MATCH == complete_status)
        _vty_append_word(vty, cmd_line, match_strs[0], complete_status);
    else
    {
        vty_print_word(vty, match_strs);
        vty_prompt(vty);
        _vty_redraw_line(vty);
    }

    vty_free_match_strs(match_strs);
    cmd_strs_free(cmd_line);

    return 0;
}

static int _vty_read(thread_t *thread)
{
    int i = 0;
    int nbytes = 0;
    unsigned char buf[VTY_READ_BUFSIZ];
    int vty_sock = THREAD_FD(thread);
    vty_t *vty = THREAD_ARG(thread);

    vty->t_read = NULL;

    /* Read raw data from socket */
    if ((nbytes = read(vty->fd, buf, VTY_READ_BUFSIZ)) <= 0)
    {
        if (nbytes < 0)
        {
            if (ERRNO_IO_RETRY(errno))
            {
                vty_event(VTY_READ, vty_sock, vty);
                return 0;
            }
            vty->monitor = 0; /* disable monitoring to avoid infinite recursion */
            printf("%s: read error on vty client fd %d, closing: %s\n",
                __func__, vty->fd, safe_strerror(errno));
        }
        
        buf_reset(vty->out_buf);
        vty->status = VTY_CLOSE;
    }

    for (i = 0; i < nbytes; i++) 
    {
        if (IAC == buf[i])
        {
            if (!vty->iac)
            {
                vty->iac = 1;
                continue;
            }
            else
            {
                vty->iac = 0;
            }
        }
      
        if (vty->iac_sb_in_progress && !vty->iac)
        {
            if (vty->sb_len < sizeof(vty->sb_buf))
                vty->sb_buf[vty->sb_len] = buf[i];
            vty->sb_len++;
            continue;
        }

        if (vty->iac)
        {
            /* In case of telnet command */
            int ret = 0;
            ret = _vty_telnet_option(vty, &buf[i], nbytes - i);
            vty->iac = 0;
            i += ret;
            continue;
        }

        if (VTY_MORE == vty->status)
        {
            switch (buf[i])
            {
            case CONTROL('C'):
            case 'q':
            case 'Q':
                _vty_buffer_reset(vty);
                break;
            default:
                break;
            }

            continue;
        }

        /* Escape character. */
        if (VTY_ESCAPE == vty->escape)
        {
            _vty_escape_map(buf[i], vty);
            continue;
        }

        /* Pre-escape status. */
        if (vty->escape == VTY_PRE_ESCAPE)
        {
            switch (buf[i])
            {
            case '[':
                vty->escape = VTY_ESCAPE;
                break;
            case 'b':
                _vty_backward_word(vty);
                vty->escape = VTY_NO_ESCAPE;
                break;
            case 'f':
                _vty_forward_word(vty);
                vty->escape = VTY_NO_ESCAPE;
                break;
            case 'd':
                _vty_forward_kill_word(vty);
                vty->escape = VTY_NO_ESCAPE;
                break;
            case CONTROL('H'):
            case 0x7f:
                _vty_backward_kill_word(vty);
                vty->escape = VTY_NO_ESCAPE;
                break;
            default:
                vty->escape = VTY_NO_ESCAPE;
                break;
            }
            
            continue;
        }

        switch (buf[i])
        {
        case CONTROL('A'):
            _vty_beginning_of_line(vty);
            break;
        case CONTROL('B'):
            _vty_backward_char(vty);
            break;
        case CONTROL('C'):
            //_vty_stop_input(vty);
            break;
        case CONTROL('D'):
            _vty_delete_char(vty);
            break;
        case CONTROL('E'):
            //_vty_end_of_line(vty);
            break;
        case CONTROL('F'):
            _vty_forward_char(vty);
            break;
        case CONTROL('H'):
        case 0x7f:
            _vty_delete_backward_char(vty);
            break;
        case CONTROL('K'):
            _vty_kill_line(vty);
            break;
        case CONTROL('N'):
            _vty_next_line(vty);
            break;
        case CONTROL('P'):
            _vty_previous_line(vty);
            break;
        case CONTROL('T'):
            //_vty_transpose_chars(vty);
            break;
        case CONTROL('U'):
            _vty_kill_line_from_beginning(vty);
            break;
        case CONTROL('W'):
            _vty_backward_kill_word(vty);
            break;
        case CONTROL('Z'):
            //_vty_end_config(vty);
            break;
        case '\n':
        case '\r':
            vty_out(vty, "%s", VTY_NEWLINE);
            vty_execute(vty);
            break;
        case '\t':
            _vty_complete_command(vty);
            break;
        case '?':
            _vty_describe_command(vty);
            break;
        case '\033':
            if (i + 1 < nbytes  && buf[i + 1] == '[')
            {
                vty->escape = VTY_ESCAPE;
                i++;
            }
            else
                vty->escape = VTY_PRE_ESCAPE;
            break;
        default:
            if (buf[i] > 31 && buf[i] < 127)
                _vty_insert_char(vty, buf[i]);
            break;
        }
    }

    /* Check status. */
    if (vty->status == VTY_CLOSE)
        vty_close(vty);
    else
    {
        vty_event(VTY_WRITE, vty_sock, vty);
        vty_event(VTY_READ, vty_sock, vty);
    }

    return 0;
}

static void _vty_thread(void *arg)
{
    thread_t thread;

    /* Fetch next active thread. */
    while(thread_fetch(vty_master, &thread))
        thread_call(&thread);

    printf("vty thread is exit!\n");
    return;
}

static void _vty_thread_init(void)
{
    int32_t rv = 0;

    pthread_t ppid = 0;
    struct sched_param param;
    pthread_attr_t attr;

    pthread_attr_init(&attr);
    param.sched_priority = 50;
    pthread_attr_setschedpolicy(&attr, SCHED_RR);
    pthread_attr_setschedparam(&attr, &param);
    pthread_attr_setinheritsched(&attr, PTHREAD_EXPLICIT_SCHED);

    rv = pthread_create(&ppid, &attr, (void *)_vty_thread, NULL);
    if (rv != 0)
        printf("can't create pthread : %d(%s)\n", rv, safe_strerror(rv));

    pthread_attr_destroy(&attr);
}

/* Create new vty structure. */
static vty_t *_vty_term_create(int vty_sock, SOCKUNION_U *su)
{
    vty_t *vty = NULL;
    
    vty = vty_create();
    
    vty->type = VTY_TERM;
    vty->node = USERNAME_NODE;
    vty->fd = vty_sock;
    vty->address = sockunion_su2str(su);
    vty->fail_count = 0;
    
    vty->cp = 0;
    vty->length = 0;
    
    memset(vty->hist, 0, sizeof(vty->hist));
    vty->hp = 0;
    vty->hindex = 0;

    vty->status = VTY_NORMAL;

    if (host.lines >= 0)
        vty->lines = host.lines;
    else
        vty->lines = -1;

    vty->iac = 0;
    vty->iac_sb_in_progress = 0;
    vty->sb_len = 0;

    vty->v_timeout = VTY_TIMEOUT_VAL;

    array_set(vtyvec, vty_sock, vty, MTYPE_VTY_TMP);
    
    /* Setting up terminal. */
    vty_will_echo(vty);
    vty_will_suppress_go_ahead(vty);

    vty_dont_linemode(vty);
    vty_do_window_size(vty);
    /* vty_dont_lflow_ahead (vty); */

    vty_prompt(vty);
    
    /* Add read/write thread. */
    vty_event(VTY_WRITE, vty_sock, vty);
    vty_event(VTY_READ, vty_sock, vty);

    return vty;
}

/* Accept connection from the network. */
static int _vty_accept(thread_t *thread)
{
    int vty_sock = 0;
    SOCKUNION_U su;
    int ret = -1;
    unsigned int on = 0;
    int accept_sock = 0;
    prefix_t *p = NULL;
    access_list_t *acl = NULL;
    char *bufp = NULL;

    accept_sock = THREAD_FD(thread);

    /* We continue hearing vty socket. */
    vty_event(VTY_SERV, accept_sock, NULL);

    memset(&su, 0, sizeof(SOCKUNION_U));

    /* We can handle IPv4 or IPv6 socket. */
    vty_sock = sockunion_accept(accept_sock, &su);
    if (vty_sock < 0)
    {
        printf("can't accept vty socket : %s\n", safe_strerror(errno));
        return -1;
    }
    set_nonblocking(vty_sock);

    p = sockunion2hostprefix(&su);

    /* VTY's accesslist apply. */
    if (AF_INET == p->family && vty_accesslist_name)
    {
        if ((acl = access_list_lookup(AFI_IP, vty_accesslist_name)) &&
            (FILTER_DENY == access_list_apply(acl, p)))
        {
            char *buf = NULL;
            printf("Vty connection refused from %s\n", (buf = sockunion_su2str(&su)));
            XFREE(MTYPE_PREFIX, buf);
            close(vty_sock);
      
            /* continue accepting connections */
            vty_event(VTY_SERV, accept_sock, NULL);
      
            prefix_free(p);
            return 0;
        }
    }

#ifdef HAVE_IPV6
    /* VTY's ipv6 accesslist apply. */
    if (AF_INET6 == p->family && vty_ipv6_accesslist_name)
    {
        if ((acl = access_list_lookup(AFI_IP6, vty_ipv6_accesslist_name))
            && (FILTER_DENY == access_list_apply(acl, p)))
        {
            char *buf = NULL;
            printf("Vty connection refused from %s\n", (buf = sockunion_su2str(&su)));
            XFREE(MTYPE_PREFIX, buf);
            close(vty_sock);
          
            /* continue accepting connections */
            vty_event(VTY_SERV, accept_sock, NULL);
          
            prefix_free(p);

            return 0;
        }
    }
#endif /* HAVE_IPV6 */
  
    prefix_free(p);

    on = 1;
    ret = setsockopt(vty_sock, IPPROTO_TCP, TCP_NODELAY, (char *)&on, sizeof(on));
    if (ret < 0)
        printf("can't set sockopt to vty_sock : %s\n", safe_strerror(errno));

    printf("Vty connection from %s\n", (bufp = sockunion_su2str(&su)));
    if (bufp)
        XFREE(MTYPE_PREFIX, bufp);

    _vty_term_create(vty_sock, &su);

    return 0;
}

/* When time out occur output message then close connection. */
static int _vty_timeout(thread_t *thread)
{
    vty_t *vty = THREAD_ARG(thread);

    vty->t_timeout = NULL;
    vty->v_timeout = 0;

    /* Clear buffer*/
    buf_reset(vty->out_buf);
    vty_out(vty, "%sVty connection is timed out.%s\n", VTY_NEWLINE, VTY_NEWLINE);

    /* Close connection. */
    vty->status = VTY_CLOSE;
    vty_close(vty);

    return 0;
}

/* Flush buffer to the vty. */
static int _vty_flush(thread_t *thread)
{
    int32_t erase = 0;
    BUF_STATUS_E flushrc = BUFFER_ERROR;
    int vty_sock = THREAD_FD(thread);
    vty_t *vty = THREAD_ARG(thread);

    vty->t_write = NULL;

    /* Tempolary disable read thread. */
    if ((0 == vty->lines) && vty->t_read)
    {
        thread_cancel(vty->t_read);
        vty->t_read = NULL;
    }

    /* Function execution continue. */
    erase = ((VTY_MORE == vty->status || VTY_MORELINE == vty->status));

    /* N.B. if width is 0, that means we don't know the window size. */
    if ((vty->lines == 0) || (vty->width == 0))
        flushrc = buf_flush_available(vty->out_buf, vty->fd);
    else if (VTY_MORELINE == vty->status)
        flushrc = buf_flush_window(vty->out_buf, vty->fd, vty->width, 1, erase, 0);
    else
        flushrc = buf_flush_window(vty->out_buf, vty->fd, vty->width,
                  vty->lines >= 0 ? vty->lines : vty->height, erase, 0);
    
    switch (flushrc)
    {
    case BUFFER_ERROR:
        vty->monitor = 0; /* disable monitoring to avoid infinite recursion */
        printf("buffer_flush failed on vty client fd %d, closing\n", vty->fd);
        buf_reset(vty->out_buf);
        vty_close(vty);
        return 0;
    case BUFFER_EMPTY:
        if (VTY_CLOSE == vty->status)
            vty_close (vty);
        else
        {
            vty->status = VTY_NORMAL;
            if (0 == vty->lines)
                vty_event(VTY_READ, vty_sock, vty);
        }
        break;
    case BUFFER_PENDING:
        /* There is more data waiting to be written. */
        vty->status = VTY_MORE;
        if (0 == vty->lines)
            vty_event(VTY_WRITE, vty_sock, vty);
        break;
    }

    return 0;
}

static int _vty_log_out(vty_t *vty, const char *level, const char *proto_str, const char *format,
    char *time_str, va_list va)
{
    int32_t ret = 0;
    int32_t len = 0;
    char *buf = NULL;


    buf = XMALLOC(MTYPE_VTY_TMP, VTY_TMP_BUFSIZ);
    if (NULL == buf)
        return -1;

    len = snprintf(buf, VTY_TMP_BUFSIZ, "%s", time_str);
    buf[len++] = ' ';

    if (level)
        ret = snprintf(buf + len, VTY_TMP_BUFSIZ - len - 1, "%s: %s: ", level, proto_str);
    else
        ret = snprintf(buf + len, VTY_TMP_BUFSIZ - len - 1, "%s: ", proto_str);

    len += ret;
    if ((ret < 0) || (len > VTY_TMP_BUFSIZ))
    {
        XFREE(MTYPE_VTY_TMP, buf);
        return -1;
    }

    ret = vsnprintf(buf + len, VTY_TMP_BUFSIZ - len - 1, format, va);
    len += ret;
    if ((ret < 0) || (len > VTY_TMP_BUFSIZ))
    {
        XFREE(MTYPE_VTY_TMP, buf);
        return -1;
    }
    
    vty_out(vty, "%s%s", buf, VTY_NEWLINE);
    buf_flush_all(vty->out_buf, vty->fd);

    XFREE(MTYPE_VTY_TMP, buf);
    return 0;
}

static int32_t _vty_user_cmp(vty_user_t *user)
{
    int32_t i = 0;
    vty_user_t *node = NULL;
    
    for(i = 0; i < array_active(vty_user); i++)
    if ((node = array_get(vty_user, i)) != NULL)
    {
        if (0 == strcmp(user->username, node->username)
            && 0 == strcmp(user->password, node->password))
        {
            return 0;
        }
    }
    
    return 1;
}

/* 在终端输出版本信息 */
void vty_version_print(vty_t *vty)
{
    struct sockaddr_in server;
    char buf[128] = {0};
    time_t temp = 0;
    
    vty_out(vty, "%s%s", CL_COPYRIGHT, VTY_NEWLINE);
    vty_out(vty, "%s %s (%x).%s", PROGNAME, host.version, device_info.dev_id, VTY_NEWLINE);
    vty_out(vty, "Compile date: %s%s", host.compile, VTY_NEWLINE);
    vty_out(vty, "Id: %03d.%03d%s", device_info.type_m, device_info.type_s, VTY_NEWLINE);
    vty_out(vty, "Mac: %02x:%02x:%02x:%02x:%02x:%02x%s",
        device_info.mac[0], device_info.mac[1], device_info.mac[2],
        device_info.mac[3], device_info.mac[4], device_info.mac[5], VTY_NEWLINE);
    server.sin_addr.s_addr = device_info.ip;
    vty_out(vty, "ip: %s ", inet_ntoa(server.sin_addr));
    server.sin_addr.s_addr = device_info.mask;
    vty_out(vty, "%s%s", inet_ntoa(server.sin_addr), VTY_NEWLINE);
    server.sin_addr.s_addr = device_info.gw;
    vty_out(vty, "route: %s%s", inet_ntoa(server.sin_addr), VTY_NEWLINE);
    temp = device_info.factory_date;
    strftime(buf, 128, "%Y-%m-%d %H:%M:%S", localtime(&temp));
    vty_out(vty, "factory date: %s%s", buf, VTY_NEWLINE);
    temp = device_info.deployment_date;
    strftime(buf, 128, "%Y-%m-%d %H:%M:%S", localtime(&temp));
    vty_out(vty, "deployment date: %s%s", buf, VTY_NEWLINE);
}

void vty_event(VTY_EVENT_E event, int sock, vty_t *vty)
{
    thread_t *thread = NULL;

    switch (event)
    {
    case VTY_SERV:
        thread = THREAD_ADD_READ(vty_master, _vty_accept, vty, sock);
        array_set(vty_serv_thread, sock, thread, MTYPE_VTY_TMP);
        break;
#if 0
    case VTYSH_SERV:
        thread_add_read(vty_master, vtysh_accept, vty, sock);
        break;
    case VTYSH_READ:
        vty->t_read = THREAD_ADD_READ(vty_master, vtysh_read, vty, sock);
        break;
    case VTYSH_WRITE:
        vty->t_write = THREAD_ADD_WRITE(vty_master, vtysh_write, vty, sock);
        break;
#endif /* VTYSH */
    case VTY_READ:
        vty->t_read = THREAD_ADD_READ(vty_master, _vty_read, vty, sock);

        /* Time out treatment. */
        if (vty->v_timeout)
        {
            if (vty->t_timeout)
                thread_cancel(vty->t_timeout);
            
            vty->t_timeout =
                THREAD_ADD_TIMER(vty_master, _vty_timeout, vty, vty->v_timeout);
        }
        break;
    case VTY_WRITE:
        if (! vty->t_write)
            vty->t_write = THREAD_ADD_WRITE(vty_master, _vty_flush, vty, sock);
        break;
    case VTY_TIMEOUT_RESET:
        if (vty->t_timeout)
        {
            thread_cancel(vty->t_timeout);
            vty->t_timeout = NULL;
        }
        if (vty->v_timeout)
        {
            vty->t_timeout = 
                THREAD_ADD_TIMER(vty_master, _vty_timeout, vty, vty->v_timeout);
        }
        break;
    }
}

static void vty_clear_buf(vty_t *vty)
{
    memset(vty->buf, 0, vty->max);
}

/* Put out prompt and wait input from user. */
void vty_prompt(vty_t *vty)
{
    cmd_node_t *node = NULL;

    if (vty->type != VTY_SHELL)
    {
        node = cmd_node_get(vty->node);

        /* 比如用户密码输入 */
        if (USERNAME_NODE == node->node
            || PASSWORD_NODE == node->node)
        {
            vty_out(vty, "%s", node->prompt);
        }
        else
        {
            vty_out(vty, node->prompt, device_info.hostname);
        }
    }
}

/* Add current command line to the history buffer. */
static void vty_hist_add(vty_t *vty)
{
    int index;

    if (vty->length == 0)
        return;

    index = vty->hindex ? vty->hindex - 1 : VTY_MAXHIST - 1;

    /* Ignore the same string as previous one. */
    if (vty->hist[index])
        if(0 == strcmp(vty->buf, vty->hist[index]))
        {
            vty->hp = vty->hindex;
            return;
        }

    /* Insert history entry. */
    if (vty->hist[vty->hindex])
        XFREE(MTYPE_VTY_HIST, vty->hist[vty->hindex]);
    vty->hist[vty->hindex] = XSTRDUP(MTYPE_VTY_HIST, vty->buf);

    /* History index rotation. */
    vty->hindex++;
    if (vty->hindex == VTY_MAXHIST)
        vty->hindex = 0;

    vty->hp = vty->hindex;
}

int vty_shell(vty_t *vty)
{
    return vty->type == VTY_SHELL ? 1 : 0;
}

/* VTY standard output function. */
int vty_out (vty_t *vty, const char *format, ...)
{
    va_list args;
    int len = 0;
    int size = 1024;
    char buf[1024];
    char *p = NULL;

    if (vty_shell(vty))
    {
        va_start(args, format);
        vprintf(format, args);
        va_end(args);
    }
    else if(VTY_CMD == vty->type)
    {
        va_start(args, format);
        vtycmd_print(format, args);
        va_end(args);
    }
    else
    {
        /* Try to write to initial buffer.  */
        va_start(args, format);
        len = vsnprintf(buf, sizeof buf, format, args);
        va_end(args);

        /* Initial buffer is not enough.  */
        if (len < 0 || len >= size)
        {
            while (1)
            {
                if (len > -1)
                    size = len + 1;
                else
                    size = size * 2;

                p = XREALLOC(MTYPE_VTY_OUT_BUF, p, size);
                if (!p)
                    return -1;

                va_start(args, format);
                len = vsnprintf(p, size, format, args);
                va_end(args);

                if (len > -1 && len < size)
                    break;
            }
        }

        /* When initial buffer is enough to store all output.  */
        if (!p)
            p = buf;

        /* Pointer p must point out buffer. */
        buf_put(vty->out_buf, p, len);

        /* If p is not different with buf, it is allocated buffer.  */
        if (p != buf)
            XFREE(MTYPE_VTY_OUT_BUF, p);
    }

    return len;
}

/* Allocate new vty struct. */
vty_t *vty_create()
{
    vty_t *vty_new = XMALLOC(MTYPE_VTY, sizeof(vty_t));

    /* Use default buffer size. */
    vty_new->out_buf = buf_create(0);   
    vty_new->buf = XMALLOC(MTYPE_VTY, VTY_BUFSIZ);
    vty_new->max = VTY_BUFSIZ;

    return vty_new;
}

/* Close vty interface.  Warning: call this only from functions that
 * will be careful not to access the vty afterwards (since it has
 * now been freed).  This is safest from top-level functions (called
 * directly by the thread dispatcher). */
void vty_close(vty_t *vty)
{
    int i = 0;

    /* Cancel threads.*/
    if (vty->t_read)
        thread_cancel (vty->t_read);
    if (vty->t_write)
        thread_cancel (vty->t_write);
    if (vty->t_timeout)
        thread_cancel (vty->t_timeout);

    /* Flush buffer. */
    buf_flush_all(vty->out_buf, vty->fd);

    /* Free input buffer. */
    buf_free(vty->out_buf);

    /* Free command history. */
    for(i = 0; i < VTY_MAXHIST; i++)
        if (vty->hist[i])
            XFREE(MTYPE_VTY_HIST, vty->hist[i]);

    /* Unset vector. */
    array_unset(vtyvec, vty->fd);

    /* Close socket. */
    if (vty->fd > 0)
        close(vty->fd);

    if (vty->address)
        XFREE(MTYPE_PREFIX, vty->address);
    if (vty->buf)
        XFREE(MTYPE_VTY, vty->buf);

    /* Check configure. */
    vty_config_unlock(vty);

    /* OK free vty. */
    XFREE(MTYPE_VTY, vty);
}

/* Execute current command line. */
int vty_execute(vty_t *vty)
{
    int ret = CMD_ERR_NO_MATCH;
    
    switch (vty->node)
    {
    case USERNAME_NODE:
        snprintf(vty->user.username, VTY_USERNAME_LEN, "%s", vty->buf);
        vty->node = PASSWORD_NODE;
        break;
        
    case PASSWORD_NODE:
        snprintf(vty->user.password, VTY_USERNAME_LEN, "%s", vty->buf);
        if (0 == _vty_user_cmp(&vty->user))
        {
            vty->node = ENABLE_NODE;
            vty_out(vty, "%s================================%s", VTY_NEWLINE, VTY_NEWLINE);
            vty_version_print(vty);
            vty_out(vty, "================================%s%s", VTY_NEWLINE, VTY_NEWLINE);
        }
        else
        {
            vty_out(vty, "Username or password is not match!!!%s%s", VTY_NEWLINE, VTY_NEWLINE);
            vty->node = USERNAME_NODE;
        }
        break;
        
    case ENABLE_NODE:
    case CONFIG_NODE:
    default:
        ret = cmd_execute(vty);
        if (vty->type != VTY_SHELL)
            vty_hist_add(vty);
        break;
    }

    /* Clear command line buffer. */
    vty->cp = vty->length = 0;
    vty_clear_buf(vty);

    if (vty->status != VTY_CLOSE )
        vty_prompt(vty);

    return ret;
}

int vty_config_lock(vty_t *vty)
{
    if (0 == vty_config)
    {
        vty->config = 1;
        vty_config = 1;
    }
    
    return vty->config;
}

int vty_config_unlock(vty_t *vty)
{
    if (1 == vty_config)
        vty_config = 0;

    if (1 == vty->config)
        vty->config = 0;
    
    return vty->config;
}

void vty_question(vty_t *vty, array_t *cmd_line)
{
    int32_t ret = CMD_ERR_NO_MATCH;
    unsigned int i = 0;
    array_t *matchs = NULL;
    unsigned int width = 0;
    desc_t *desc = NULL;

    matchs = cmd_describe_command(cmd_line, vty, &ret);
    vty_out(vty, "%s", VTY_NEWLINE);

    /* Ambiguous and no match error. */
    switch (ret)
    {
    case CMD_ERR_AMBIGUOUS:
        fprintf (stdout,"%% Ambiguous command.\n");
        return;
        break;
    case CMD_ERR_NO_MATCH:
        fprintf (stdout,"%% There is no matched command.\n");
        return;
        break;
    }

    /* Get width of command string. */
    for (i = 0; i < array_active(matchs); i++)
    if ((desc = array_get(matchs, i)) != NULL)
    {
        unsigned int len = 0;

        if (desc->cmd[0] == '\0')
            continue;

        len = strlen(desc->cmd);
        if (desc->cmd[0] == '.')
            len--;

        if (width < len)
            width = len;
    }

    for (i = 0; i < array_active(matchs); i++)
    if ((desc = array_get(matchs, i)) != NULL)
    {
        if (desc->cmd[0] == '\0')
            continue;

        if (!desc->str)
            vty_out(vty, "    %-s%s", desc->cmd[0] == '.' ? desc->cmd + 1 : desc->cmd, VTY_NEWLINE);
        else
            vty_out(vty, "    %-*s  %s%s", width, desc->cmd[0] == '.' ? desc->cmd + 1 : desc->cmd, desc->str, VTY_NEWLINE);
    }

    array_free(matchs, MTYPE_CLI);
    return;
}

void vty_print_word(vty_t *vty, char *strs[])
{
    char *str = NULL;
    unsigned int i = 0;

    vty_out(vty, "%s", VTY_NEWLINE);
    for(i = 0; (str = strs[i]) != NULL; i++)
        vty_out(vty, "%s", str);
}

void vty_free_match_strs(char *match_strs[])
{
    char *str = NULL;
    unsigned int i = 0;

    for(i = 0; (str = match_strs[i]) != NULL; i++)
        XFREE(MTYPE_CLI, str);

    XFREE(MTYPE_CLI, match_strs);
}

/* Send WILL TELOPT_ECHO to remote server. */
void vty_will_echo(vty_t *vty)
{
    unsigned char cmd[] = {IAC, WILL, TELOPT_ECHO, '\0'};
    vty_out(vty, "%s", cmd);
}

/* Make suppress Go-Ahead telnet option. */
void vty_will_suppress_go_ahead(vty_t *vty)
{
    unsigned char cmd[] = {IAC, WILL, TELOPT_SGA, '\0'};
    vty_out(vty, "%s", cmd);
}

/* Make don't use linemode over telnet. */
void vty_dont_linemode(vty_t *vty)
{
    unsigned char cmd[] = {IAC, DONT, TELOPT_LINEMODE, '\0'};
    vty_out(vty, "%s", cmd);
}

/* Use window size. */
void vty_do_window_size(vty_t *vty)
{
    unsigned char cmd[] = {IAC, DO, TELOPT_NAWS, '\0'};
    vty_out(vty, "%s", cmd);
}

/* Make vty server socket. */
void vty_serv_sock_family(const char* addr, unsigned short port, int family)
{
    int32_t ret = 0;
    SOCKUNION_U su;
    int accept_sock = 0;
    void *naddr = NULL;

    memset(&su, 0, sizeof(SOCKUNION_U));
    su.sa.sa_family = family;
    if(addr)
    switch(family)
    {
    case AF_INET:
        naddr = &su.sin.sin_addr;
#ifdef HAVE_IPV6
    case AF_INET6:
        naddr = &su.sin6.sin6_addr;
#endif  
    }

    if(naddr)
    switch(inet_pton(family, addr, naddr))
    {
    case -1:
        printf("bad address %s\n", addr);
        naddr = NULL;
        break;
    case 0:
        printf("error translating address %s: %s\n", addr, safe_strerror(errno));
        naddr = NULL;
    }

    /* Make new socket. */
    accept_sock = sockunion_stream_socket(&su);
    if (accept_sock < 0)
        return;

    /* This is server, so reuse address. */
    sockunion_reuseaddr(accept_sock);

    /* Bind socket to universal address and given port. */
    ret = sockunion_bind(accept_sock, &su, port, naddr);
    if (ret < 0)
    {
        close(accept_sock); /* Avoid sd leak. */
        return;
    }

    /* Listen socket under queue 3. */
    ret = listen(accept_sock, 3);
    if (ret < 0) 
    {
        printf("can't listen socket\n");
        close(accept_sock); /* Avoid sd leak. */
        return;
    }

    /* Add vty server event. */
    vty_event(VTY_SERV, accept_sock, NULL);
}

/* Small utility function which output log to the VTY. */
void vty_log(const char *level, const char *proto_str, const char *format, char *time_str, va_list va)
{
    uint32_t i = 0;
    vty_t *vty = NULL;
    
    if (!vtyvec)
        return;

    for(i = 0; i < array_active(vtyvec); i++)
    if ((vty = array_get(vtyvec, i)) != NULL)
    if (vty->monitor)
    {
        va_list ac;
        va_copy(ac, va);
        _vty_log_out(vty, level, proto_str, format, time_str, ac);
        va_end(ac);
    }
}

/* vty的print函数. */
void vty_print(const char *format, va_list va)
{
    vty_t *vty = NULL;
    char *buf = NULL;
    uint32_t i = 0;
    bool is_vty = FALSE;

    if (vtycmd_connect())
    {
        is_vty = TRUE;
        vtycmd_print(format, va);
    }
    else if(vtyvec)
    {
        for(i = 0; i < array_active(vtyvec); i++)
        if ((vty = array_get(vtyvec, i)) != NULL)
        {
            is_vty = TRUE;
            buf = XMALLOC(MTYPE_VTY_TMP, VTY_TMP_BUFSIZ);
            if (NULL == buf)
                return;

            vsnprintf(buf, VTY_TMP_BUFSIZ, format, va);
            vty_out(vty, "%s", buf);
            buf_flush_all(vty->out_buf, vty->fd);

            XFREE(MTYPE_VTY_TMP, buf);
        }
    }

    if (!is_vty)
    {
        vprintf(format, va);
    }
}


/* Reset all VTY status. */
void vty_reset(void)
{
    unsigned int i = 0;
    vty_t *vty = NULL;
    thread_t *serv_thread;

    for(i = 0; i < array_active(vtyvec); i++)
    if ((vty = array_get(vtyvec, i)) != NULL)
    {
        buf_reset(vty->out_buf);
        vty->status = VTY_CLOSE;
        vty_close(vty);
    }

    for (i = 0; i < array_active(vty_serv_thread); i++)
    if ((serv_thread = array_get(vty_serv_thread, i)) != NULL)
    {
        thread_cancel(serv_thread);
        array_get(vty_serv_thread, i) = NULL;
        close(i);
    }

    return;
}

/* Install vty's own commands like `who' command. */
void vty_init(void)
{
    vty_user_t *user;

    vtyvec = array_init(ARRAY_MIN_SIZE, MTYPE_VTY_TMP);

    vty_serv_thread = array_init(ARRAY_MIN_SIZE, MTYPE_VTY_TMP);

    vty_user = array_init(ARRAY_MIN_SIZE, MTYPE_VTY_TMP);
    user = XMALLOC(MTYPE_VTY_TMP, sizeof(vty_user_t));
    snprintf(user->username, VTY_USERNAME_LEN, "%s", VTY_USERNAME_DEFAULT);
    snprintf(user->password, VTY_USERNAME_LEN, "%s", VTY_PASSWORD_DEFAULT);
    user->level = 255;
    array_append(vty_user, user, MTYPE_VTY_TMP);

    vty_master = thread_master_create();

    _vty_thread_init();
}
/************************ (C) COPYRIGHT LandPower ***** END OF FILE ****************/