Linux-AIO/AIO.xs

#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"

#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.h>
#include <signal.h>
#include <sched.h>

typedef void *InputStream; /* hack, but 5.6.1 is simply toooo old ;) */
typedef void *OutputStream; /* hack, but 5.6.1 is simply toooo old ;) */
typedef void *InOutStream; /* hack, but 5.6.1 is simply toooo old ;) */

#define STACKSIZE 1024 /* yeah */

enum { REQ_QUIT, REQ_OPEN, REQ_CLOSE, REQ_READ, REQ_WRITE, REQ_STAT, REQ_LSTAT, REQ_FSTAT};

typedef struct {
  char stack[STACKSIZE];
} aio_thread;

typedef struct {
  int type;
  aio_thread *thread;

  SV *savesv;

  int fd;
  off_t offset;
  size_t length;
  ssize_t result;
  mode_t mode; /* open */
  int errorno;
  SV *data, *callback;
  void *dataptr;
  STRLEN dataoffset;

  struct stat64 *statdata;
} aio_cb;

typedef aio_cb *aio_req;

static int started;
static int nreqs;
static int reqpipe[2], respipe[2];

static int aio_proc(void *arg);

static void
start_thread(void)
{
  aio_thread *thr;

  New (0, thr, 1, aio_thread);

  if (clone (aio_proc,
             &(thr->stack[STACKSIZE]),
             CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND,
             thr) >= 0)
    started++;
  else
    Safefree (thr);
}

static void
end_thread(void)
{
  aio_req req;
  New (0, req, 1, aio_cb);
  req->type = REQ_QUIT;
  write (reqpipe[1], &req, sizeof (aio_req));
}

static void
send_req (aio_req req)
{
  nreqs++;
  write (reqpipe[1], &req, sizeof (aio_req));
}

static void
read_write (pTHX_ int dowrite, int fd, off_t offset, size_t length,
            SV *data, STRLEN dataoffset, SV*callback)
{
  aio_req req;
  STRLEN svlen;
  char *svptr = SvPV (data, svlen);

  SvUPGRADE (data, SVt_PV);
  SvPOK_on (data);

  if (dataoffset < 0)
    dataoffset += svlen;

  if (dataoffset < 0 || dataoffset > svlen)
    croak ("data offset outside of string");

  if (dowrite)
    {
      /* write: check length and adjust. */
      if (length < 0 || length + dataoffset > svlen)
        length = svlen - dataoffset;
    }
  else
    {
      /* read: grow scalar as necessary */
      svptr = SvGROW (data, length + dataoffset);
    }

  if (length < 0)
    croak ("length must not be negative");

  New (0, req, 1, aio_cb);

  if (!req)
    croak ("out of memory during aio_req allocation");

  req->type = dowrite ? REQ_WRITE : REQ_READ;
  req->fd = fd;
  req->offset = offset;
  req->length = length;
  req->data = SvREFCNT_inc (data);
  req->dataptr = (char *)svptr + dataoffset;
  req->callback = SvREFCNT_inc (callback);

  send_req (req);
}

static int
poll_cb (pTHX)
{
  dSP;
  int count = 0;
  aio_req req;

  while (read (respipe[0], (void *)&req, sizeof (req)) == sizeof (req))
    {
      if (req->type == REQ_QUIT)
        {
          Safefree (req->thread);
          started--;
        }
      else
        {
          int errorno = errno;
          errno = req->errorno;

          if (req->savesv)
            SvREFCNT_dec (req->savesv);

          if (req->type == REQ_READ)
            SvCUR_set (req->data, req->dataoffset
                                  + req->result > 0 ? req->result : 0);

          if (req->type == REQ_STAT || req->type == REQ_LSTAT || req->type == REQ_FSTAT)
            {
              PL_laststype            = req->type == REQ_LSTAT ? OP_LSTAT : OP_STAT;
              PL_laststatval          = req->result;
              PL_statcache.st_dev     = req->statdata->st_dev;
              PL_statcache.st_ino     = req->statdata->st_ino;
              PL_statcache.st_mode    = req->statdata->st_mode;
              PL_statcache.st_nlink   = req->statdata->st_nlink;
              PL_statcache.st_uid     = req->statdata->st_uid;
              PL_statcache.st_gid     = req->statdata->st_gid;
              PL_statcache.st_rdev    = req->statdata->st_rdev;
              PL_statcache.st_size    = req->statdata->st_size;
              PL_statcache.st_atime   = req->statdata->st_atime;
              PL_statcache.st_mtime   = req->statdata->st_mtime;
              PL_statcache.st_ctime   = req->statdata->st_ctime;
              PL_statcache.st_blksize = req->statdata->st_blksize;
              PL_statcache.st_blocks  = req->statdata->st_blocks;

              Safefree (req->statdata);
            }

          PUSHMARK (SP);
          XPUSHs (sv_2mortal (newSViv (req->result)));
          PUTBACK;
          call_sv (req->callback, G_VOID);
          SPAGAIN;
          
          SvREFCNT_dec (req->data);
          SvREFCNT_dec (req->callback);

          errno = errorno;
          nreqs--;
          count++;
        }

      Safefree (req);
    }

  return count;
}

static sigset_t fullsigset;

#undef errno
#include <asm/unistd.h>

static int
aio_proc(void *thr_arg)
{
  aio_thread *thr = thr_arg;
  aio_req req;
  int errno;

  /* we rely on gcc's ability to create closures. */
  _syscall3(int,read,int,fd,char *,buf,size_t,count)
  _syscall3(int,write,int,fd,char *,buf,size_t,count)

  _syscall3(int,open,char *,pathname,int,flags,mode_t,mode)
  _syscall1(int,close,int,fd)

  _syscall4(int,pread,int,fd,char *,buf,size_t,count,off_t,offset)
  _syscall4(int,pwrite,int,fd,char *,buf,size_t,count,off_t,offset)

  _syscall2(int,stat64, const char *, filename, struct stat64 *, buf)
  _syscall2(int,lstat64, const char *, filename, struct stat64 *, buf)
  _syscall2(int,fstat64, int, fd, struct stat64 *, buf)

  sigprocmask (SIG_SETMASK, &fullsigset, 0);

  /* then loop */
  while (read (reqpipe[0], (void *)&req, sizeof (req)) == sizeof (req))
    {
      req->thread = thr;
      errno = 0;

      if (req->type == REQ_READ)
        req->result = pread (req->fd, req->dataptr, req->length, req->offset);
      else if (req->type == REQ_WRITE)
        req->result = pwrite (req->fd, req->dataptr, req->length, req->offset);
      else if (req->type == REQ_OPEN)
        req->result = open (req->dataptr, req->fd, req->mode);
      else if (req->type == REQ_CLOSE)
        req->result = close (req->fd);
      else if (req->type == REQ_STAT)
        req->result = stat64 (req->dataptr, req->statdata);
      else if (req->type == REQ_LSTAT)
        req->result = lstat64 (req->dataptr, req->statdata);
      else if (req->type == REQ_FSTAT)
        req->result = fstat64 (req->fd, req->statdata);
      else
        {
          write (respipe[1], (void *)&req, sizeof (req));
          break;
        }

      req->errorno = errno;
      write (respipe[1], (void *)&req, sizeof (req));
    }

  return 0;
}

MODULE = Linux::AIO                PACKAGE = Linux::AIO

BOOT:
{
        sigfillset (&fullsigset);
        sigdelset (&fullsigset, SIGTERM);
        sigdelset (&fullsigset, SIGQUIT);
        sigdelset (&fullsigset, SIGABRT);
        sigdelset (&fullsigset, SIGINT);

        if (pipe (reqpipe) || pipe (respipe))
          croak ("unable to initialize request or result pipe");

        if (fcntl (respipe[0], F_SETFL, O_NONBLOCK))
          croak ("cannot set result pipe to nonblocking mode");
}

void
min_parallel(nthreads)
        int     nthreads
        PROTOTYPE: $
        CODE:
        while (nthreads > started)
          start_thread ();

void
max_parallel(nthreads)
        int     nthreads
        PROTOTYPE: $
        CODE:
        int cur = started;
        while (cur > nthreads)
          {          
            end_thread ();
            cur--;
          }

        poll_cb ();
        while (started > nthreads)
          {
            sched_yield ();
            fcntl (respipe[0], F_SETFL, 0);
            poll_cb ();
            fcntl (respipe[0], F_SETFL, O_NONBLOCK);
          }

void
aio_open(pathname,flags,mode,callback)
        SV *    pathname
        int     flags
        int     mode
        SV *    callback
        PROTOTYPE: $$$$
        CODE:
        aio_req req;

        New (0, req, 1, aio_cb);

        if (!req)
          croak ("out of memory during aio_req allocation");

        req->type = REQ_OPEN;
        req->savesv = newSVsv (pathname);
        req->dataptr = SvPV_nolen (req->savesv);
        req->fd = flags;
        req->mode = mode;
        req->callback = SvREFCNT_inc (callback);

        send_req (req);

void
aio_close(fh,callback)
        InputStream     fh
        SV *            callback
        PROTOTYPE: $
        CODE:
        aio_req req;

        New (0, req, 1, aio_cb);

        if (!req)
          croak ("out of memory during aio_req allocation");

        req->type = REQ_CLOSE;
        req->fd = PerlIO_fileno (fh);
        req->callback = SvREFCNT_inc (callback);

        send_req (req);

void
aio_read(fh,offset,length,data,dataoffset,callback)
        InputStream     fh
        UV              offset
        IV              length
        SV *            data
        IV              dataoffset
        SV *            callback
        PROTOTYPE: $$$$$$
        CODE:
        read_write (aTHX_ 0, PerlIO_fileno (fh), offset, length, data, dataoffset, callback);

void
aio_write(fh,offset,length,data,dataoffset,callback)
        OutputStream    fh
        UV              offset
        IV              length
        SV *            data
        IV              dataoffset
        SV *            callback
        PROTOTYPE: $$$$$$
        CODE:
        read_write (aTHX_ 1, PerlIO_fileno (fh), offset, length, data, dataoffset, callback);

void
aio_stat(fh_or_path,callback)
        SV *            fh_or_path
        SV *            callback
        PROTOTYPE: $$
        ALIAS:
           aio_lstat = 1
        CODE:
        aio_req req;

        New (0, req, 1, aio_cb);

        if (!req)
          croak ("out of memory during aio_req allocation");

        New (0, req->statdata, 1, struct stat64);

        if (!req->statdata)
          croak ("out of memory during aio_req->statdata allocation");

        if (SvPOK (fh_or_path))
          {
            req->type = ix ? REQ_LSTAT : REQ_STAT;
            req->savesv = newSVsv (fh_or_path);
            req->dataptr = SvPV_nolen (req->savesv);
          }
        else
          {
            req->type = REQ_FSTAT;
            req->fd = PerlIO_fileno (IoIFP (sv_2io (fh_or_path)));
          }

        req->callback = SvREFCNT_inc (callback);

        send_req (req);

int
poll_fileno()
        PROTOTYPE:
        CODE:
        RETVAL = respipe[0];
        OUTPUT:
        RETVAL

int
poll_cb(...)
        PROTOTYPE:
        CODE:
        RETVAL = poll_cb (aTHX);
        OUTPUT:
        RETVAL

int
nreqs()
        PROTOTYPE:
        CODE:
        RETVAL = nreqs;
        OUTPUT:
        RETVAL

Revision:	1.13
Committed:	Mon Apr 1 20:30:08 2002 UTC (22 years, 1 month ago) by root
Branch:	MAIN
Changes since 1.12:	+121 -40 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	#include "EXTERN.h"
2			#include "perl.h"
3			#include "XSUB.h"
4
5			#include <sys/types.h>
6	root	1.13	#include <sys/stat.h>
7	root	1.1	#include <unistd.h>
8	root	1.5	#include <fcntl.h>
9	root	1.8	#include <signal.h>
10	root	1.1	#include <sched.h>
11
12	root	1.13	typedef void InputStream; / hack, but 5.6.1 is simply toooo old ;) */
13			typedef void OutputStream; / hack, but 5.6.1 is simply toooo old ;) */
14	root	1.12	typedef void InOutStream; / hack, but 5.6.1 is simply toooo old ;) */
15
16	root	1.8	#define STACKSIZE 1024 /* yeah */
17	root	1.1
18	root	1.13	enum { REQ_QUIT, REQ_OPEN, REQ_CLOSE, REQ_READ, REQ_WRITE, REQ_STAT, REQ_LSTAT, REQ_FSTAT};
19	root	1.1
20			typedef struct {
21			char stack[STACKSIZE];
22			} aio_thread;
23
24			typedef struct {
25			int type;
26			aio_thread *thread;
27
28	root	1.13	SV *savesv;
29
30	root	1.1	int fd;
31			off_t offset;
32			size_t length;
33	root	1.2	ssize_t result;
34	root	1.8	mode_t mode; /* open */
35	root	1.1	int errorno;
36	root	1.5	SV data, callback;
37	root	1.1	void *dataptr;
38	root	1.2	STRLEN dataoffset;
39	root	1.13
40			struct stat64 *statdata;
41	root	1.1	} aio_cb;
42
43			typedef aio_cb *aio_req;
44
45			static int started;
46	root	1.5	static int nreqs;
47	root	1.1	static int reqpipe[2], respipe[2];
48
49	root	1.2	static int aio_proc(void *arg);
50
51	root	1.1	static void
52			start_thread(void)
53			{
54	root	1.2	aio_thread *thr;
55
56			New (0, thr, 1, aio_thread);
57
58			if (clone (aio_proc,
59			&(thr->stack[STACKSIZE]),
60			CLONE_VM\|CLONE_FS\|CLONE_FILES\|CLONE_SIGHAND,
61			thr) >= 0)
62			started++;
63			else
64			Safefree (thr);
65	root	1.1	}
66
67			static void
68			end_thread(void)
69			{
70	root	1.5	aio_req req;
71			New (0, req, 1, aio_cb);
72			req->type = REQ_QUIT;
73	root	1.1	write (reqpipe[1], &req, sizeof (aio_req));
74	root	1.2	}
75
76			static void
77	root	1.8	send_req (aio_req req)
78			{
79			nreqs++;
80			write (reqpipe[1], &req, sizeof (aio_req));
81			}
82
83			static void
84	root	1.5	read_write (pTHX_ int dowrite, int fd, off_t offset, size_t length,
85			SV data, STRLEN dataoffset, SVcallback)
86	root	1.2	{
87	root	1.5	aio_req req;
88			STRLEN svlen;
89			char *svptr = SvPV (data, svlen);
90
91	root	1.13	SvUPGRADE (data, SVt_PV);
92			SvPOK_on (data);
93
94	root	1.5	if (dataoffset < 0)
95			dataoffset += svlen;
96
97			if (dataoffset < 0 \|\| dataoffset > svlen)
98			croak ("data offset outside of string");
99
100			if (dowrite)
101			{
102			/* write: check length and adjust. */
103			if (length < 0 \|\| length + dataoffset > svlen)
104			length = svlen - dataoffset;
105			}
106			else
107			{
108			/* read: grow scalar as necessary */
109			svptr = SvGROW (data, length + dataoffset);
110			}
111
112			if (length < 0)
113			croak ("length must not be negative");
114
115			New (0, req, 1, aio_cb);
116
117			if (!req)
118			croak ("out of memory during aio_req allocation");
119
120			req->type = dowrite ? REQ_WRITE : REQ_READ;
121			req->fd = fd;
122			req->offset = offset;
123			req->length = length;
124			req->data = SvREFCNT_inc (data);
125	root	1.6	req->dataptr = (char *)svptr + dataoffset;
126	root	1.5	req->callback = SvREFCNT_inc (callback);
127
128	root	1.8	send_req (req);
129	root	1.5	}
130
131			static int
132			poll_cb (pTHX)
133			{
134			dSP;
135			int count = 0;
136			aio_req req;
137
138			while (read (respipe[0], (void *)&req, sizeof (req)) == sizeof (req))
139			{
140			if (req->type == REQ_QUIT)
141			{
142			Safefree (req->thread);
143			started--;
144			}
145			else
146			{
147			int errorno = errno;
148			errno = req->errorno;
149
150	root	1.13	if (req->savesv)
151			SvREFCNT_dec (req->savesv);
152
153	root	1.5	if (req->type == REQ_READ)
154	root	1.6	SvCUR_set (req->data, req->dataoffset
155			+ req->result > 0 ? req->result : 0);
156	root	1.5
157	root	1.13	if (req->type == REQ_STAT \|\| req->type == REQ_LSTAT \|\| req->type == REQ_FSTAT)
158			{
159			PL_laststype = req->type == REQ_LSTAT ? OP_LSTAT : OP_STAT;
160			PL_laststatval = req->result;
161			PL_statcache.st_dev = req->statdata->st_dev;
162			PL_statcache.st_ino = req->statdata->st_ino;
163			PL_statcache.st_mode = req->statdata->st_mode;
164			PL_statcache.st_nlink = req->statdata->st_nlink;
165			PL_statcache.st_uid = req->statdata->st_uid;
166			PL_statcache.st_gid = req->statdata->st_gid;
167			PL_statcache.st_rdev = req->statdata->st_rdev;
168			PL_statcache.st_size = req->statdata->st_size;
169			PL_statcache.st_atime = req->statdata->st_atime;
170			PL_statcache.st_mtime = req->statdata->st_mtime;
171			PL_statcache.st_ctime = req->statdata->st_ctime;
172			PL_statcache.st_blksize = req->statdata->st_blksize;
173			PL_statcache.st_blocks = req->statdata->st_blocks;
174
175			Safefree (req->statdata);
176			}
177
178	root	1.5	PUSHMARK (SP);
179			XPUSHs (sv_2mortal (newSViv (req->result)));
180			PUTBACK;
181			call_sv (req->callback, G_VOID);
182			SPAGAIN;
183
184			SvREFCNT_dec (req->data);
185			SvREFCNT_dec (req->callback);
186
187			errno = errorno;
188			nreqs--;
189			count++;
190			}
191
192			Safefree (req);
193			}
194
195			return count;
196	root	1.2	}
197
198	root	1.8	static sigset_t fullsigset;
199
200	root	1.2	#undef errno
201			#include <asm/unistd.h>
202
203			static int
204			aio_proc(void *thr_arg)
205			{
206			aio_thread *thr = thr_arg;
207	root	1.9	aio_req req;
208	root	1.2	int errno;
209
210	root	1.11	/* we rely on gcc's ability to create closures. */
211	root	1.13	_syscall3(int,read,int,fd,char *,buf,size_t,count)
212			_syscall3(int,write,int,fd,char *,buf,size_t,count)
213
214	root	1.11	_syscall3(int,open,char *,pathname,int,flags,mode_t,mode)
215			_syscall1(int,close,int,fd)
216
217	root	1.13	_syscall4(int,pread,int,fd,char *,buf,size_t,count,off_t,offset)
218			_syscall4(int,pwrite,int,fd,char *,buf,size_t,count,off_t,offset)
219
220			_syscall2(int,stat64, const char , filename, struct stat64 , buf)
221			_syscall2(int,lstat64, const char , filename, struct stat64 , buf)
222			_syscall2(int,fstat64, int, fd, struct stat64 *, buf)
223
224	root	1.8	sigprocmask (SIG_SETMASK, &fullsigset, 0);
225	root	1.2
226			/* then loop */
227			while (read (reqpipe[0], (void *)&req, sizeof (req)) == sizeof (req))
228			{
229			req->thread = thr;
230	root	1.8	errno = 0;
231	root	1.2
232	root	1.13	if (req->type == REQ_READ)
233			req->result = pread (req->fd, req->dataptr, req->length, req->offset);
234			else if (req->type == REQ_WRITE)
235			req->result = pwrite (req->fd, req->dataptr, req->length, req->offset);
236	root	1.8	else if (req->type == REQ_OPEN)
237	root	1.13	req->result = open (req->dataptr, req->fd, req->mode);
238	root	1.10	else if (req->type == REQ_CLOSE)
239	root	1.13	req->result = close (req->fd);
240			else if (req->type == REQ_STAT)
241			req->result = stat64 (req->dataptr, req->statdata);
242			else if (req->type == REQ_LSTAT)
243			req->result = lstat64 (req->dataptr, req->statdata);
244			else if (req->type == REQ_FSTAT)
245			req->result = fstat64 (req->fd, req->statdata);
246	root	1.2	else
247			{
248			write (respipe[1], (void *)&req, sizeof (req));
249			break;
250			}
251
252	root	1.8	req->errorno = errno;
253	root	1.2	write (respipe[1], (void *)&req, sizeof (req));
254			}
255
256			return 0;
257	root	1.1	}
258
259			MODULE = Linux::AIO PACKAGE = Linux::AIO
260
261			BOOT:
262			{
263	root	1.8	sigfillset (&fullsigset);
264	root	1.9	sigdelset (&fullsigset, SIGTERM);
265			sigdelset (&fullsigset, SIGQUIT);
266			sigdelset (&fullsigset, SIGABRT);
267			sigdelset (&fullsigset, SIGINT);
268	root	1.8
269	root	1.1	if (pipe (reqpipe) \|\| pipe (respipe))
270			croak ("unable to initialize request or result pipe");
271	root	1.5
272			if (fcntl (respipe[0], F_SETFL, O_NONBLOCK))
273			croak ("cannot set result pipe to nonblocking mode");
274	root	1.1	}
275
276			void
277			min_parallel(nthreads)
278			int nthreads
279	root	1.5	PROTOTYPE: $
280	root	1.1	CODE:
281			while (nthreads > started)
282			start_thread ();
283
284			void
285			max_parallel(nthreads)
286			int nthreads
287	root	1.5	PROTOTYPE: $
288	root	1.1	CODE:
289	root	1.5	int cur = started;
290			while (cur > nthreads)
291			{
292			end_thread ();
293			cur--;
294			}
295
296			poll_cb ();
297	root	1.1	while (started > nthreads)
298	root	1.5	{
299			sched_yield ();
300	root	1.12	fcntl (respipe[0], F_SETFL, 0);
301	root	1.5	poll_cb ();
302	root	1.12	fcntl (respipe[0], F_SETFL, O_NONBLOCK);
303	root	1.5	}
304	root	1.1
305			void
306	root	1.8	aio_open(pathname,flags,mode,callback)
307	root	1.13	SV * pathname
308	root	1.8	int flags
309			int mode
310			SV * callback
311			PROTOTYPE: $$$$
312			CODE:
313			aio_req req;
314
315			New (0, req, 1, aio_cb);
316
317			if (!req)
318			croak ("out of memory during aio_req allocation");
319
320			req->type = REQ_OPEN;
321	root	1.13	req->savesv = newSVsv (pathname);
322			req->dataptr = SvPV_nolen (req->savesv);
323	root	1.8	req->fd = flags;
324			req->mode = mode;
325	root	1.10	req->callback = SvREFCNT_inc (callback);
326
327			send_req (req);
328
329			void
330			aio_close(fh,callback)
331	root	1.13	InputStream fh
332	root	1.10	SV * callback
333			PROTOTYPE: $
334			CODE:
335			aio_req req;
336
337			New (0, req, 1, aio_cb);
338
339			if (!req)
340			croak ("out of memory during aio_req allocation");
341
342			req->type = REQ_CLOSE;
343			req->fd = PerlIO_fileno (fh);
344	root	1.13	req->callback = SvREFCNT_inc (callback);
345
346			send_req (req);
347
348			void
349			aio_read(fh,offset,length,data,dataoffset,callback)
350			InputStream fh
351			UV offset
352			IV length
353			SV * data
354			IV dataoffset
355			SV * callback
356			PROTOTYPE: $$$$$$
357			CODE:
358			read_write (aTHX_ 0, PerlIO_fileno (fh), offset, length, data, dataoffset, callback);
359
360			void
361			aio_write(fh,offset,length,data,dataoffset,callback)
362			OutputStream fh
363			UV offset
364			IV length
365			SV * data
366			IV dataoffset
367			SV * callback
368			PROTOTYPE: $$$$$$
369			CODE:
370			read_write (aTHX_ 1, PerlIO_fileno (fh), offset, length, data, dataoffset, callback);
371
372			void
373			aio_stat(fh_or_path,callback)
374			SV * fh_or_path
375			SV * callback
376			PROTOTYPE: $$
377			ALIAS:
378			aio_lstat = 1
379			CODE:
380			aio_req req;
381
382			New (0, req, 1, aio_cb);
383
384			if (!req)
385			croak ("out of memory during aio_req allocation");
386
387			New (0, req->statdata, 1, struct stat64);
388
389			if (!req->statdata)
390			croak ("out of memory during aio_req->statdata allocation");
391
392			if (SvPOK (fh_or_path))
393			{
394			req->type = ix ? REQ_LSTAT : REQ_STAT;
395			req->savesv = newSVsv (fh_or_path);
396			req->dataptr = SvPV_nolen (req->savesv);
397			}
398			else
399			{
400			req->type = REQ_FSTAT;
401			req->fd = PerlIO_fileno (IoIFP (sv_2io (fh_or_path)));
402			}
403
404	root	1.8	req->callback = SvREFCNT_inc (callback);
405
406			send_req (req);
407	root	1.5
408			int
409			poll_fileno()
410			PROTOTYPE:
411			CODE:
412			RETVAL = respipe[0];
413			OUTPUT:
414			RETVAL
415
416			int
417	root	1.6	poll_cb(...)
418	root	1.5	PROTOTYPE:
419			CODE:
420			RETVAL = poll_cb (aTHX);
421			OUTPUT:
422			RETVAL
423
424			int
425			nreqs()
426			PROTOTYPE:
427			CODE:
428			RETVAL = nreqs;
429			OUTPUT:
430			RETVAL
431