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/* $Id$ */
#include "bbs.h"

//kcwu: 80x24 一般使用者名單 1.9k, 含 header 2.4k
// 一般文章推文頁約 2590 bytes
#define OBUFSIZE  3072
#define IBUFSIZE  128

/* realXbuf is Xbuf+3 because hz convert library requires buf[-2]. */
#define CVTGAP    (3)

#ifdef DEBUG
#define register
#endif

static unsigned char real_outbuf[OBUFSIZE + CVTGAP*2] = "   ", 
             real_inbuf [IBUFSIZE + CVTGAP*2] = "   ";

// use defines instead - it is discovered that sometimes the input/output buffer was overflow,
// without knowing why.
// static unsigned char *outbuf = real_outbuf + 3, *inbuf = real_inbuf + 3;
#define inbuf  (real_inbuf +CVTGAP)
#define outbuf (real_outbuf+CVTGAP)

static int      obufsize = 0, ibufsize = 0;
static int      icurrchar = 0;

#ifdef DBG_OUTRPT
// output counter
static unsigned long szTotalOutput = 0, szLastOutput = 0;
extern unsigned char fakeEscape;
unsigned char fakeEscape = 0;

static unsigned char fakeEscFilter(unsigned char c)
{
    if (!fakeEscape) return c;
    if (c == ESC_CHR) return '*';
    else if (c == '\n') return 'N';
    else if (c == '\r') return 'R';
    else if (c == '\b') return 'B';
    else if (c == '\t') return 'I';
    return c;
}
#endif // DBG_OUTRPT

/* ----------------------------------------------------- */
/* convert routines                                      */
/* ----------------------------------------------------- */
#ifdef CONVERT

inline static ssize_t input_wrapper(void *buf, ssize_t count) {
    /* input_wrapper is a special case.
     * because we may do nothing,
     * a if-branch is better than a function-pointer call.
     */
    if(input_type)
    return (*input_type)(buf, count);
    else
    return count;
}

inline static int read_wrapper(int fd, void *buf, size_t count) {
    return (*read_type)(fd, buf, count);
}

inline static int write_wrapper(int fd, void *buf, size_t count) {
    return (*write_type)(fd, buf, count);
}
#endif

/* ----------------------------------------------------- */
/* output routines                                       */
/* ----------------------------------------------------- */
void
oflush(void)
{
    if (obufsize) {
    STATINC(STAT_SYSWRITESOCKET);
#ifdef CONVERT
    write_wrapper(1, outbuf, obufsize);
#else
    write(1, outbuf, obufsize);
#endif
    obufsize = 0;
    }

#ifdef DBG_OUTRPT
    // if (0)
    {
    static char xbuf[128];
    sprintf(xbuf, ESC_STR "[s" ESC_STR "[H" " [%lu/%lu] " ESC_STR "[u",
        szLastOutput, szTotalOutput);
    write(1, xbuf, strlen(xbuf));
    szLastOutput = 0; 
    }
#endif // DBG_OUTRPT

    fsync(1);
}

void
output(const char *s, int len)
{
#ifdef DBG_OUTRPT
    int i = 0;
    if (fakeEscape)
    for (i = 0; i < obufsize; i++)
        outbuf[i] = fakeEscFilter(outbuf[i]);

    szTotalOutput += len; 
    szLastOutput  += len;
#endif // DBG_OUTRPT

    /* Invalid if len >= OBUFSIZE */
    assert(len<OBUFSIZE);

    if (obufsize + len > OBUFSIZE) {
    STATINC(STAT_SYSWRITESOCKET);
#ifdef CONVERT
    write_wrapper(1, outbuf, obufsize);
#else
    write(1, outbuf, obufsize);
#endif
    obufsize = 0;
    }
    memcpy(outbuf + obufsize, s, len);
    obufsize += len;
}

int
ochar(int c)
{

#ifdef DBG_OUTRPT
    c = fakeEscFilter(c);
    szTotalOutput ++; 
    szLastOutput ++;
#endif // DBG_OUTRPT

    if (obufsize > OBUFSIZE - 1) {
    STATINC(STAT_SYSWRITESOCKET);
    /* suppose one byte data doesn't need to be converted. */
    write(1, outbuf, obufsize);
    obufsize = 0;
    }
    outbuf[obufsize++] = c;
    return 0;
}

/* ----------------------------------------------------- */
/* input routines                                        */
/* ----------------------------------------------------- */

static int      i_newfd = 0;
static struct timeval i_to, *i_top = NULL;
static int      (*flushf) () = NULL;

void
add_io(int fd, int timeout)
{
    i_newfd = fd;
    if (timeout) {
    i_to.tv_sec = timeout;
    i_to.tv_usec = 16384;   /* Ptt: 改成16384 避免不按時for loop吃cpu
                 * time 16384 約每秒64次 */
    i_top = &i_to;
    } else
    i_top = NULL;
}

int
num_in_buf(void)
{
    if (ibufsize <= icurrchar)
    return 0;
    return ibufsize - icurrchar;
}

int
input_isfull(void)
{
    return ibufsize >= IBUFSIZE;
}

/*
 * dogetch() is not reentrant-safe. SIGUSR[12] might happen at any time, and
 * dogetch() might be called again, and then ibufsize/icurrchar/inbuf might
 * be inconsistent. We try to not segfault here...
 */

static int
dogetch(void)
{
    ssize_t         len;
    static time4_t  lastact;
    if (ibufsize <= icurrchar) {

    if (flushf)
        (*flushf) ();

    refresh();

    if (i_newfd) {

        struct timeval  timeout;
        fd_set          readfds;

        if (i_top)
        timeout = *i_top;   /* copy it because select() might
                     * change it */

        FD_ZERO(&readfds);
        FD_SET(0, &readfds);
        FD_SET(i_newfd, &readfds);

        /* jochang: modify first argument of select from FD_SETSIZE */
        /* since we are only waiting input from fd 0 and i_newfd(>0) */

        STATINC(STAT_SYSSELECT);
        while ((len = select(i_newfd + 1, &readfds, NULL, NULL,
                i_top ? &timeout : NULL)) < 0) {
        if (errno != EINTR)
            abort_bbs(0);
        /* raise(SIGHUP); */
        }

        if (len == 0){
        syncnow();
        return I_TIMEOUT;
        }

        if (i_newfd && FD_ISSET(i_newfd, &readfds)){
        syncnow();
        return I_OTHERDATA;
        }
    }

#ifdef NOKILLWATERBALL
    if( currutmp && currutmp->msgcount && !reentrant_write_request )
        write_request(1);
#endif

    STATINC(STAT_SYSREADSOCKET);

    do {
        len = tty_read(inbuf, IBUFSIZE);
        /* tty_read will handle abort_bbs.
         * len <= 0: read more */
#ifdef CONVERT
        if(len > 0)
        len = input_wrapper(inbuf, len);
#endif
#ifdef DBG_OUTRPT
        // if (0)
        {
        static char xbuf[128];
        sprintf(xbuf, ESC_STR "[s" ESC_STR "[2;1H [%ld] " 
            ESC_STR "[u", len);
        write(1, xbuf, strlen(xbuf));
        fsync(1);
        }
#endif // DBG_OUTRPT

    } while (len <= 0);

    ibufsize = len;
    icurrchar = 0;
    }

    if (currutmp) {
    syncnow();
    /* 3 秒內超過兩 byte 才算 active, anti-antiidle.
     * 不過方向鍵等組合鍵不止 1 byte */
    if (now - lastact < 3)
        currutmp->lastact = now;
    lastact = now;
    }

    // CRLF Handle:
    //
    // (UNIX) LF
    // (WIN)  CRLF
    // (MAC)  CR
    //
    // to work in a compatible way, (see KEY_ENTER definition)
    // let KEY_ENTER = CR

    {
    unsigned char c = (unsigned char) inbuf[icurrchar++];

    // CR LF are treated as one.
    if (c == KEY_CR)
    {
        // peak next character.
        if (icurrchar < ibufsize && inbuf[icurrchar] == KEY_LF)
        icurrchar ++;
        return KEY_ENTER;
    } 
    else if (c == KEY_LF)
    {
        // XXX it is reported that still some users
        // experience double ENTERs. We are not sure if there
        // are still any stupid clients. But if any, you
        // can reject the LFs. According the the compatibility
        // test, most clients send CR only so it should be fine.
#ifdef ACCEPT_LF
        return KEY_ENTER;
#else
        return KEY_UNKNOWN;
#endif
    }

    // XXX also treat ^H and 127 (KEY_BS2) the same one?
    // else if (c == KEY_BS2)
    // {
    //   return KEY_BS;
    // }
    
    return c;
    }
}

#ifdef DEBUG
/*
 * These are for terminal keys debug
 */
void
_debug_print_ibuffer()
{
    static int y = 0;
    int i = 0;

    move(y % b_lines, 0);
    for (i = 0; i < t_columns; i++) 
    outc(' ');
    move(y % b_lines, 0);
    prints("%d. Current Buffer: %d/%d, ", y+1, icurrchar, ibufsize);
    outs(ANSI_COLOR(1) "[" ANSI_RESET);
    for (i = 0; i < ibufsize; i++)
    {
    int c = (unsigned char)inbuf[i];
    if(c < ' ')
    {
        prints(ANSI_COLOR(1;33) "0x%02x" ANSI_RESET, c);
    } else {
        outc(c);
    }
    }
    outs(ANSI_COLOR(1) "]" ANSI_RESET);
    y++;
    move(y % b_lines, 0);
    for (i = 0; i < t_columns; i++) 
    outc(' ');
}

int 
_debug_check_keyinput()
{
    int dbcsaware = 0;
    int flExit = 0;

    clear();
    while(!flExit)
    {
    int i = 0;
    move(b_lines, 0);
    for(i=0; i<t_columns; i++)
        outc(' ');
    move(b_lines, 0);
    if(dbcsaware)
    {
        outs( ANSI_REVERSE "游標在此" ANSI_RESET
            " 測試中文模式會不會亂送鍵。 'q' 離開, 'd' 回英文模式 ");
        move(b_lines, 4);
    } else {
        outs("Waiting for key input. 'q' to exit, 'd' to try dbcs-aware");
    }
    refresh();
    wait_input(-1, 0);
    switch(dogetch())
    {
        case 'd':
        dbcsaware = !dbcsaware;
        break;
        case 'q':
        flExit = 1;
        break;
    }
    _debug_print_ibuffer();
    while(num_in_buf() > 0)
        dogetch();
    }
    return 0;
}

#endif

static int      water_which_flag = 0;

#ifndef vkey
int 
vkey(void)
{
    return igetch();
}
#endif

int
igetch(void)
{
    register int ch, mode = 0, last = 0;
    while (1) {
    ch = dogetch();

    /* for escape codes, check
     * http://support.dell.com/support/edocs/systems/pe2650/en/ug/5g387ad0.htm
     */
        if (mode == 0 && ch == KEY_ESC)
        mode = 1;
        else if (mode == 1) { 

        /* Escape sequence */

            if (ch == '[' || ch == 'O')
        { mode = 2; last = ch; }
            else {
                KEY_ESC_arg = ch;
                return KEY_ESC;
        }

        } 
    else if (mode == 2)
    {
        /* ^[ or ^O,
         * ordered by frequency */

        if(ch >= 'A' && ch <= 'D')  /* Cursor key */
        {
        return  KEY_UP + (ch - 'A');
        }
        else if (ch >= '1' && ch <= '6') /* Ins Del Home End PgUp PgDn */
        { 
        mode = 3; last = ch; 
        continue;
        }
        else if(ch == 'O')
        {
        mode = 4; 
        continue;
        }
        else if(ch == 'Z')
        {
        return KEY_STAB;
        }  
        else if (ch == '0')
        {
        if (dogetch() == 'Z')
            return KEY_STAB;
        else
            return KEY_UNKNOWN;
        }
        else if (last == 'O') {
        /* ^[O ... */
        if (ch >= 'A' && ch <= 'D')
            return KEY_UP + (ch - 'A');
        if (ch >= 'P' && ch <= 'S')     // vt100 k1-4
            return KEY_F1 + (ch - 'P');
        if (ch >= 'T' && ch <= '[')     // putty vt100+ F5-F12
            return KEY_F5 + (ch - 'T');
        if (ch >= 't' && ch <= 'z')     // vt100 F5-F11
            return KEY_F5 + (ch - 't');
        if (ch >= 'p' && ch <= 's')     // Old (num or fn)kbd 4 keys
            return KEY_F1 + (ch - 'p');
        else if (ch == 'a')         // DELL spec
            return KEY_F12;
        }
        else return KEY_UNKNOWN;
    }  
    else if (mode == 3)
    { 
        /* ^[[1-6] */

        /* ~: Ins Del Home End PgUp PgDn */
        if(ch == '~')
        {
        // vt220 style
        if (last >= '1' && last <= '6')
            return KEY_HOME + (last - '1');
        // else, unknown.
        return KEY_UNKNOWN;
        }
        else if (last == '1')
        {
        if (ch >= '1' && ch <= '6')
        {
            // use num_in_buf() to prevent waiting keys
            if (num_in_buf() && dogetch() == '~') /* must be '~' */
            return KEY_F1 + ch - '1';
        }
        else if (ch >= '7' && ch <= '9')
        {
            // use num_in_buf() to prevent waiting keys
            if (num_in_buf() && dogetch() == '~') /* must be '~' */
            return KEY_F6 + ch - '7';
        }
        return KEY_UNKNOWN;
        } 
        else if (last == '2')
        {
        if (ch >= '0' && ch <= '4')
        {
            // use inbuf() to prevent waiting keys
            if (num_in_buf() && dogetch() == '~') /* hope you are '~' */
            return KEY_F9 + ch - '0';
        }
        return KEY_UNKNOWN;
        }
        // if fall here, then escape sequence is broken.
        return KEY_UNKNOWN;
    }
        else          //  here is switch for default keys
    switch (ch) { // XXX: indent error
#ifdef DEBUG
    case Ctrl('Q'):{
        struct rusage ru;
        getrusage(RUSAGE_SELF, &ru);
        vmsgf("sbrk: %d KB, idrss: %d KB, isrss: %d KB",
         ((int)sbrk(0) - 0x8048000) / 1024,
         (int)ru.ru_idrss, (int)ru.ru_isrss);
    }
        continue;
#endif
    case Ctrl('L'):
        redrawwin();
        refresh();
        continue;

    case Ctrl('U'):
        if (currutmp != NULL && currutmp->mode != EDITING
        && currutmp->mode != LUSERS && currutmp->mode) {

        screen_backup_t old_screen;
        int     oldroll = roll;
        int             my_newfd;

        scr_dump(&old_screen);
        my_newfd = i_newfd;
        i_newfd = 0;

        t_users();

        i_newfd = my_newfd;
        roll = oldroll;
        scr_restore(&old_screen);
        continue;
        } 
            return ch;
    case KEY_TAB:
        if (WATERMODE(WATER_ORIG) || WATERMODE(WATER_NEW))
        if (currutmp != NULL && watermode > 0) {
            check_water_init();
            watermode = (watermode + water_which->count)
            % water_which->count + 1;
            t_display_new();
            continue;
        }
            return ch;

    case Ctrl('R'):
        if (currutmp == NULL)
        return (ch);

        if (currutmp->msgs[0].pid &&
        WATERMODE(WATER_OFO) && wmofo == NOTREPLYING) {
        int my_newfd;
        screen_backup_t old_screen;

        scr_dump(&old_screen);

        my_newfd = i_newfd;
        i_newfd = 0;
        my_write2();
            scr_restore(&old_screen);
        i_newfd = my_newfd;
        continue;
        } else if (!WATERMODE(WATER_OFO)) {
        check_water_init();
        if (watermode > 0) {
            watermode = (watermode + water_which->count)
            % water_which->count + 1;
            t_display_new();
            continue;
        } else if (currutmp->mode == 0 &&
            (currutmp->chatid[0] == 2 || currutmp->chatid[0] == 3) &&
               water_which->count != 0 && watermode == 0) {
            /* 第二次按 Ctrl-R */
            watermode = 1;
            t_display_new();
            continue;
        } else if (watermode == -1 && currutmp->msgs[0].pid) {
            /* 第一次按 Ctrl-R (必須先被丟過水球) */
            screen_backup_t old_screen;
            int             my_newfd;
            scr_dump(&old_screen);

            /* 如果正在talk的話先不處理對方送過來的封包 (不去select) */
            my_newfd = i_newfd;
            i_newfd = 0;
            show_call_in(0, 0);
            watermode = 0;
#ifndef PLAY_ANGEL
            my_write(currutmp->msgs[0].pid, "水球丟過去: ",
                currutmp->msgs[0].userid, WATERBALL_GENERAL, NULL);
#else
            switch (currutmp->msgs[0].msgmode) {
            case MSGMODE_TALK:
            case MSGMODE_WRITE:
                my_write(currutmp->msgs[0].pid, "水球丟過去: ",
                    currutmp->msgs[0].userid, WATERBALL_GENERAL, NULL);
                break;
            case MSGMODE_FROMANGEL:
                my_write(currutmp->msgs[0].pid, "再問他一次: ",
                    currutmp->msgs[0].userid, WATERBALL_ANGEL, NULL);
                break;
            case MSGMODE_TOANGEL:
                my_write(currutmp->msgs[0].pid, "回答小主人: ",
                    currutmp->msgs[0].userid, WATERBALL_ANSWER, NULL);
                break;
            }
#endif
            i_newfd = my_newfd;

            /* 還原螢幕 */
            scr_restore(&old_screen);
            continue;
        }
        }
        return ch;

    case Ctrl('T'):
        if (WATERMODE(WATER_ORIG) || WATERMODE(WATER_NEW)) {
        if (watermode > 0) {
            check_water_init();
            if (watermode > 1)
            watermode--;
            else
            watermode = water_which->count;
            t_display_new();
            continue;
        }
        }
            return ch;

    case Ctrl('F'):
        if (WATERMODE(WATER_NEW)) {
        if (watermode > 0) {
            check_water_init();
            if (water_which_flag == (int)water_usies)
            water_which_flag = 0;
            else
            water_which_flag =
                (water_which_flag + 1) % (int)(water_usies + 1);
            if (water_which_flag == 0)
            water_which = &water[0];
            else
            water_which = swater[water_which_flag - 1];
            watermode = 1;
            t_display_new();
            continue;
        }
        }
            return ch;

    case Ctrl('G'):
        if (WATERMODE(WATER_NEW)) {
        if (watermode > 0) {
            check_water_init();
            water_which_flag = (water_which_flag + water_usies) % (water_usies + 1);
            if (water_which_flag == 0)
            water_which = &water[0];
            else
            water_which = swater[water_which_flag - 1];
            watermode = 1;
            t_display_new();
            continue;
        }
        }
        return ch;

    default:
            return ch;
    }
    }
    // should not reach here. just to make compiler happy.
    return 0;
}

/*
 * wait user input anything for f seconds.
 * if f < 0, then wait forever.
 * Return 1 if anything available.
 */
int 
wait_input(float f, int bIgnoreBuf)
{
    int sel = 0;
    fd_set readfds;
    struct timeval tv, *ptv = &tv;

    if(!bIgnoreBuf && num_in_buf() > 0)
    return 1;

    FD_ZERO(&readfds);
    FD_SET(0, &readfds);

    if(f > 0)
    {
    tv.tv_sec = (long) f;
    tv.tv_usec = (f - (long)f) * 1000000L;
    } else
    ptv = NULL;

#ifdef STATINC
    STATINC(STAT_SYSSELECT);
#endif

    do {
    if(!bIgnoreBuf && num_in_buf() > 0)
        return 1;
    sel = select(1, &readfds, NULL, NULL, ptv);
    } while (sel < 0 && errno == EINTR);
    /* EINTR, interrupted. I don't care! */

    if(sel == 0)
    return 0;

    return 1;
}

void 
drop_input(void)
{
    icurrchar = ibufsize = 0;
}

/*
 * wait user input for f seconds.
 * return 1 if control key c is available.
 */
int 
peek_input(float f, int c)
{
    int i = 0;
    assert (c > 0 && c < ' '); // only ^x keys are safe to be detected.
    // other keys may fall into escape sequence.

    if (wait_input(f, 1) && (IBUFSIZE > ibufsize))
    {
    int len = tty_read(inbuf + ibufsize, IBUFSIZE - ibufsize);
#ifdef CONVERT
    if(len > 0)
        len = input_wrapper(inbuf+ibufsize, len);
#endif
    if (len > 0)
        ibufsize += len;
    }
    for (i = icurrchar; i < ibufsize; i++)
    {
    if (inbuf[i] == c)
        return 1;
    }
    return 0;
}

static int 
getdata2vgetflag(int echo)
{
    assert(echo != GCARRY);

    if (echo == LCECHO)
    echo = VGET_LOWERCASE;
    else if (echo == NUMECHO)
    echo = VGET_DIGITS;
    else if (echo == NOECHO)
    echo = VGET_PASSWORD;
    else
    echo = VGET_DEFAULT;

    return echo;
}

/* Ptt */
int
getdata_buf(int line, int col, const char *prompt, char *buf, int len, int echo)
{
    move(line, col);
    if(prompt && *prompt) outs(prompt);
    return vgetstr(buf, len, getdata2vgetflag(echo), buf);
}


int
getdata_str(int line, int col, const char *prompt, char *buf, int len, int echo, const char *defaultstr)
{
    move(line, col);
    if(prompt && *prompt) outs(prompt);
    return vgetstr(buf, len, getdata2vgetflag(echo), defaultstr);
}

int
getdata(int line, int col, const char *prompt, char *buf, int len, int echo)
{
    move(line, col);
    if(prompt && *prompt) outs(prompt);
    return vgets(buf, len, getdata2vgetflag(echo));
}

/* vim:sw=4
 */