sysdeps_win32.c

来自「Android 一些工具」· C语言 代码 · 共 1,954 行 · 第 1/4 页

        bip->can_read = 1;
        SetEvent( bip->evt_read );
    }
  
    BIPD(( "bip_buffer_write: exit %d->%d count %d (as=%d ae=%d be=%d cw=%d cr=%d\n", 
            bip->fdin, bip->fdout, count, bip->a_start, bip->a_end, bip->b_end, bip->can_write, bip->can_read ));
    LeaveCriticalSection( &bip->lock );

    return count;
 }

static int
bip_buffer_read( BipBuffer  bip, void*  dst, int  len )
{
    int  avail, count = 0;
    
    if (len <= 0)
        return 0;
    
    BIPD(( "bip_buffer_read: enter %d->%d len %d\n", bip->fdin, bip->fdout, len ));
    
    EnterCriticalSection( &bip->lock );
    while ( !bip->can_read )
    {
#if 0
        LeaveCriticalSection( &bip->lock );
        errno = EAGAIN;
        return -1;
#else    
        int  ret;
        LeaveCriticalSection( &bip->lock );
        
        if (bip->closed) {
            errno = EPIPE;
            return -1;
        }

        ret = WaitForSingleObject( bip->evt_read, INFINITE );
        if (ret != WAIT_OBJECT_0) { /* probably closed buffer */
            D( "bip_buffer_read: error %d->%d WaitForSingleObject returned %d, error %ld\n", bip->fdin, bip->fdout, ret, GetLastError());
            return 0;
        }
        if (bip->closed) {
            errno = EPIPE;
            return -1;
        }
        EnterCriticalSection( &bip->lock );
#endif        
    }

    BIPD(( "bip_buffer_read: exec %d->%d len %d\n", bip->fdin, bip->fdout, len ));
   
    avail = bip->a_end - bip->a_start;
    assert( avail > 0 );  /* since can_read is TRUE */
    
    if (avail > len)
        avail = len;
    
    memcpy( dst, bip->buff + bip->a_start, avail );
    dst   += avail;
    count += avail;
    len   -= avail;
    
    bip->a_start += avail;
    if (bip->a_start < bip->a_end)
        goto Exit;
    
    bip->a_start = 0;
    bip->a_end   = bip->b_end;
    bip->b_end   = 0;
    
    avail = bip->a_end;
    if (avail > 0) {
        if (avail > len)
            avail = len;
        memcpy( dst, bip->buff, avail );
        count += avail;
        bip->a_start += avail;
        
        if ( bip->a_start < bip->a_end )
            goto Exit;
            
        bip->a_start = bip->a_end = 0;
    }
    
    bip->can_read = 0;
    ResetEvent( bip->evt_read );

Exit:
    assert( count > 0 );

    if (!bip->can_write ) {
        bip->can_write = 1;
        SetEvent( bip->evt_write );
    }
    
    BIPDUMP( (const unsigned char*)dst - count, count );
    BIPD(( "bip_buffer_read: exit %d->%d count %d (as=%d ae=%d be=%d cw=%d cr=%d\n", 
            bip->fdin, bip->fdout, count, bip->a_start, bip->a_end, bip->b_end, bip->can_write, bip->can_read ));
    LeaveCriticalSection( &bip->lock );
    
    return count;
}
 
typedef struct SocketPairRec_ 
{
    BipBufferRec  a2b_bip;
    BipBufferRec  b2a_bip;
    FH            a_fd;
    int           used;
    
} SocketPairRec;

void _fh_socketpair_init( FH  f )
{
    f->fh_pair = NULL;
}

static int
_fh_socketpair_close( FH  f )
{
    if ( f->fh_pair ) {
        SocketPair  pair = f->fh_pair;

        if ( f == pair->a_fd ) {
            pair->a_fd = NULL;
        }
        
        bip_buffer_close( &pair->b2a_bip );
        bip_buffer_close( &pair->a2b_bip );

        if ( --pair->used == 0 ) {
            bip_buffer_done( &pair->b2a_bip );
            bip_buffer_done( &pair->a2b_bip );
            free( pair );
        }
        f->fh_pair = NULL;
    }
    return 0;
}

static int
_fh_socketpair_lseek( FH  f, int pos, int  origin )
{
    errno = ESPIPE;
    return -1;
}

static int
_fh_socketpair_read( FH  f, void* buf, int  len )
{
    SocketPair  pair = f->fh_pair;
    BipBuffer   bip;

    if (!pair)
        return -1;

    if ( f == pair->a_fd )
        bip = &pair->b2a_bip;
    else
        bip = &pair->a2b_bip;

    return bip_buffer_read( bip, buf, len );
}

static int
_fh_socketpair_write( FH  f, const void*  buf, int  len )
{
    SocketPair  pair = f->fh_pair;
    BipBuffer   bip;

    if (!pair)
        return -1;

    if ( f == pair->a_fd )
        bip = &pair->a2b_bip;
    else
        bip = &pair->b2a_bip;

    return bip_buffer_write( bip, buf, len );
}


static void  _fh_socketpair_hook( FH  f, int  event, EventHook  hook );  /* forward */

static const FHClassRec  _fh_socketpair_class =
{
    _fh_socketpair_init,
    _fh_socketpair_close,
    _fh_socketpair_lseek,
    _fh_socketpair_read,
    _fh_socketpair_write,
    _fh_socketpair_hook
};


int  adb_socketpair( int  sv[2] )
{
    FH          fa, fb;
    SocketPair  pair;

    fa = _fh_alloc( &_fh_socketpair_class );
    fb = _fh_alloc( &_fh_socketpair_class );

    if (!fa || !fb)
        goto Fail;

    pair = malloc( sizeof(*pair) );
    if (pair == NULL) {
        D("adb_socketpair: not enough memory to allocate pipes\n" );
        goto Fail;
    }

    bip_buffer_init( &pair->a2b_bip );
    bip_buffer_init( &pair->b2a_bip );

    fa->fh_pair = pair;
    fb->fh_pair = pair;
    pair->used  = 2;
    pair->a_fd  = fa;

    sv[0] = _fh_to_int(fa);
    sv[1] = _fh_to_int(fb);
    
    pair->a2b_bip.fdin  = sv[0];
    pair->a2b_bip.fdout = sv[1];
    pair->b2a_bip.fdin  = sv[1];
    pair->b2a_bip.fdout = sv[0];

    snprintf( fa->name, sizeof(fa->name), "%d(pair:%d)", sv[0], sv[1] );
    snprintf( fb->name, sizeof(fb->name), "%d(pair:%d)", sv[1], sv[0] );
    D( "adb_socketpair: returns (%d, %d)\n", sv[0], sv[1] );
    return 0;

Fail:
    _fh_close(fb);
    _fh_close(fa);
    return -1;
}

/**************************************************************************/
/**************************************************************************/
/*****                                                                *****/
/*****    fdevents emulation                                          *****/
/*****                                                                *****/
/*****   this is a very simple implementation, we rely on the fact    *****/
/*****   that ADB doesn't use FDE_ERROR.                              *****/
/*****                                                                *****/
/**************************************************************************/
/**************************************************************************/

#define FATAL(x...) fatal(__FUNCTION__, x)

#if DEBUG
static void dump_fde(fdevent *fde, const char *info)
{
    fprintf(stderr,"FDE #%03d %c%c%c %s\n", fde->fd,
            fde->state & FDE_READ ? 'R' : ' ',
            fde->state & FDE_WRITE ? 'W' : ' ',
            fde->state & FDE_ERROR ? 'E' : ' ',
            info);
}
#else
#define dump_fde(fde, info) do { } while(0)
#endif

#define FDE_EVENTMASK  0x00ff
#define FDE_STATEMASK  0xff00

#define FDE_ACTIVE     0x0100
#define FDE_PENDING    0x0200
#define FDE_CREATED    0x0400

static void fdevent_plist_enqueue(fdevent *node);
static void fdevent_plist_remove(fdevent *node);
static fdevent *fdevent_plist_dequeue(void);

static fdevent list_pending = {
    .next = &list_pending,
    .prev = &list_pending,
};

static fdevent **fd_table = 0;
static int       fd_table_max = 0;

typedef struct EventLooperRec_*  EventLooper;

typedef struct EventHookRec_
{
    EventHook    next;
    FH           fh;
    HANDLE       h;
    int          wanted;   /* wanted event flags */
    int          ready;    /* ready event flags  */
    void*        aux;
    void        (*prepare)( EventHook  hook );
    int         (*start)  ( EventHook  hook );
    void        (*stop)   ( EventHook  hook );
    int         (*check)  ( EventHook  hook );
    int         (*peek)   ( EventHook  hook );
} EventHookRec;

static EventHook  _free_hooks;

static EventHook
event_hook_alloc( FH  fh )
{
    EventHook  hook = _free_hooks;
    if (hook != NULL)
        _free_hooks = hook->next;
    else {
        hook = malloc( sizeof(*hook) );
        if (hook == NULL)
            fatal( "could not allocate event hook\n" );
    }
    hook->next   = NULL;
    hook->fh     = fh;
    hook->wanted = 0;
    hook->ready  = 0;
    hook->h      = INVALID_HANDLE_VALUE;
    hook->aux    = NULL;

    hook->prepare = NULL;
    hook->start   = NULL;
    hook->stop    = NULL;
    hook->check   = NULL;
    hook->peek    = NULL;
    
    return hook;
}

static void
event_hook_free( EventHook  hook )
{
    hook->fh     = NULL;
    hook->wanted = 0;
    hook->ready  = 0;
    hook->next   = _free_hooks;
    _free_hooks  = hook;
}


static void
event_hook_signal( EventHook  hook )
{
    FH        f   = hook->fh;
    int       fd  = _fh_to_int(f);
    fdevent*  fde = fd_table[ fd - WIN32_FH_BASE ];
    
    if (fde != NULL && fde->fd == fd) {
        if ((fde->state & FDE_PENDING) == 0) {
            fde->state |= FDE_PENDING;
            fdevent_plist_enqueue( fde );
        }
        fde->events |= hook->wanted;
    }
}


#define  MAX_LOOPER_HANDLES  WIN32_MAX_FHS

typedef struct EventLooperRec_
{
    EventHook    hooks;
    HANDLE       htab[ MAX_LOOPER_HANDLES ];
    int          htab_count;

} EventLooperRec;

static EventHook*
event_looper_find_p( EventLooper  looper, FH  fh )
{
    EventHook  *pnode = &looper->hooks;
    EventHook   node  = *pnode;
    for (;;) {
        if ( node == NULL || node->fh == fh )
            break;
        pnode = &node->next;
        node  = *pnode;
    }
    return  pnode;
}

static void
event_looper_hook( EventLooper  looper, int  fd, int  events )
{
    FH          f = _fh_from_int(fd);
    EventHook  *pnode;
    EventHook   node;
    
    if (f == NULL)  /* invalid arg */ {
        D("event_looper_hook: invalid fd=%d\n", fd);
        return;
    }

    pnode = event_looper_find_p( looper, f );
    node  = *pnode;
    if ( node == NULL ) {
        node       = event_hook_alloc( f );
        node->next = *pnode;
        *pnode     = node;
    }

    if ( (node->wanted & events) != events ) {
        /* this should update start/stop/check/peek */
        D("event_looper_hook: call hook for %d (new=%x, old=%x)\n",
           fd, node->wanted, events);
        f->clazz->_fh_hook( f, events & ~node->wanted, node );
        node->wanted |= events;
    } else {
        D("event_looper_hook: ignoring events %x for %d wanted=%x)\n", 
           events, fd, node->wanted);
    }
}

static void
event_looper_unhook( EventLooper  looper, int  fd, int  events )
{
    FH          fh    = _fh_from_int(fd);
    EventHook  *pnode = event_looper_find_p( looper, fh );
    EventHook   node  = *pnode;
    
    if (node != NULL) {
        int  events2 = events & node->wanted;
        if ( events2 == 0 ) {
            D( "event_looper_unhook: events %x not registered for fd %d\n", events, fd );
            return;
        }
        node->wanted &= ~events2;
        if (!node->wanted) {
            *pnode = node->next;
            event_hook_free( node );
        }
    }
}

static EventLooperRec  win32_looper;

static void fdevent_init(void)
{
    win32_looper.htab_count = 0;
    win32_looper.hooks      = NULL;
}

static void fdevent_connect(fdevent *fde)
{
    EventLooper  looper = &win32_looper;
    int          events = fde->state & FDE_EVENTMASK;
    
    if (events != 0)
        event_looper_hook( looper, fde->fd, events );
}

static void fdevent_disconnect(fdevent *fde)
{
    EventLooper  looper = &win32_looper;
    int          events = fde->state & FDE_EVENTMASK;
    
    if (events != 0)
        event_looper_unhook( looper, fde->fd, events );
}

static void fdevent_update(fdevent *fde, unsigned events)
{
    EventLooper  looper  = &win32_looper;
    unsigned     events0 = fde->state & FDE_EVENTMASK;

    if (events != events0) {
        int  removes = events0 & ~events;
        int  adds    = events  & ~events0;
        if (removes) {
            D("fdevent_update: remove %x from %d\n", removes, fde->fd);
            event_looper_unhook( looper, fde->fd, removes );
        }
        if (adds) {
            D("fdevent_update: add %x to %d\n", adds, fde->fd);
            event_looper_hook  ( looper, fde->fd, adds );
        }
    }
}

static void fdevent_process()
{
    EventLooper  looper = &win32_looper;
    EventHook    hook;
    int          gotone = 0;
    
    /* if we have at least one ready hook, execute it/them */
    for (hook = looper->hooks; hook; hook = hook->next) {