IO-AIO/AIO.xs

#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>
#if __linux
#include <sys/syscall.h>
#endif

#include <pthread.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 ;) */

#if __ia64
# define STACKSIZE 65536
#else
# define STACKSIZE  4096
#endif

enum {
  REQ_QUIT,
  REQ_OPEN, REQ_CLOSE,
  REQ_READ, REQ_WRITE, REQ_READAHEAD,
  REQ_STAT, REQ_LSTAT, REQ_FSTAT, REQ_UNLINK,
  REQ_FSYNC, REQ_FDATASYNC,
};

typedef struct aio_cb {
  struct aio_cb *volatile next;

  int type;

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

  Stat_t *statdata;
} aio_cb;

typedef aio_cb *aio_req;

static int started;
static volatile int nreqs;
static int max_outstanding = 1<<30;
static int respipe [2];

static pthread_mutex_t reslock = PTHREAD_MUTEX_INITIALIZER;
static pthread_mutex_t reqlock = PTHREAD_MUTEX_INITIALIZER;
static pthread_cond_t  reqwait = PTHREAD_COND_INITIALIZER;

static volatile aio_req reqs, reqe; /* queue start, queue end */
static volatile aio_req ress, rese; /* queue start, queue end */

static void
poll_wait ()
{
  if (nreqs && !ress)
    {
      fd_set rfd;
      FD_ZERO(&rfd);
      FD_SET(respipe [0], &rfd);

      select (respipe [0] + 1, &rfd, 0, 0, 0);
    }
}

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

  pthread_mutex_lock (&reslock);

  {
    /* read any signals sent by the worker threads */
    char buf [32];
    while (read (respipe [0], buf, 32) > 0)
      ;
  }

  req = ress;
  ress = rese = 0;

  pthread_mutex_unlock (&reslock);

  while (req)
    {
      nreqs--;

      if (req->type == REQ_QUIT)
        started--;
      else
        {
          int errorno = errno;
          errno = req->errorno;

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

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

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

          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   = *(req->statdata);

              Safefree (req->statdata);
            }

          ENTER;
          PUSHMARK (SP);
          XPUSHs (sv_2mortal (newSViv (req->result)));

          if (req->type == REQ_OPEN)
            {
              /* convert fd to fh */
              SV *fh;

              PUTBACK;
              call_pv ("IO::AIO::_fd2fh", G_SCALAR | G_EVAL);
              SPAGAIN;

              fh = SvREFCNT_inc (POPs);

              PUSHMARK (SP);
              XPUSHs (sv_2mortal (fh));
            }

          if (SvOK (req->callback))
            {
              PUTBACK;
              call_sv (req->callback, G_VOID | G_EVAL);
              SPAGAIN;
            }

          LEAVE;
          
          if (req->callback)
            SvREFCNT_dec (req->callback);

          errno = errorno;
          count++;
        }

      prv = req;
      req = req->next;
      Safefree (prv);

      /* TODO: croak on errors? */
    }

  return count;
}

static void *aio_proc(void *arg);

static void
start_thread (void)
{
  sigset_t fullsigset, oldsigset;
  pthread_t tid;
  pthread_attr_t attr;

  pthread_attr_init (&attr);
  pthread_attr_setstacksize (&attr, STACKSIZE);
  pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);

  sigfillset (&fullsigset);
  sigprocmask (SIG_SETMASK, &fullsigset, &oldsigset);

  if (pthread_create (&tid, &attr, aio_proc, 0) == 0)
    started++;

  sigprocmask (SIG_SETMASK, &oldsigset, 0);
}

static void
send_req (aio_req req)
{
  nreqs++;

  pthread_mutex_lock (&reqlock);

  req->next = 0;

  if (reqe)
    {
      reqe->next = req;
      reqe = req;
    }
  else
    reqe = reqs = req;

  pthread_cond_signal (&reqwait);
  pthread_mutex_unlock (&reqlock);

  while (nreqs > max_outstanding)
    {
      poll_wait ();
      poll_cb ();
    }
}

static void
end_thread (void)
{
  aio_req req;
  New (0, req, 1, aio_cb);
  req->type = REQ_QUIT;

  send_req (req);
}

static void *
aio_proc (void *thr_arg)
{
  aio_req req;
  int type;

  do
    {
      pthread_mutex_lock (&reqlock);

      for (;;)
        {
          req = reqs;

          if (reqs)
            {
              reqs = reqs->next;
              if (!reqs) reqe = 0;
            }

          if (req)
            break;

          pthread_cond_wait (&reqwait, &reqlock);
        }

      pthread_mutex_unlock (&reqlock);
     
      errno = 0; /* strictly unnecessary */

      type = req->type;

      switch (type)
        {
          case REQ_READ:      req->result = pread     (req->fd, req->dataptr, req->length, req->offset); break;
          case REQ_WRITE:     req->result = pwrite    (req->fd, req->dataptr, req->length, req->offset); break;
#if SYS_readahead
          case REQ_READAHEAD: req->result = readahead (req->fd, req->offset, req->length); break;
#else
          case REQ_READAHEAD: req->result = -1; errno = ENOSYS; break;
#endif

          case REQ_STAT:      req->result = stat      (req->dataptr, req->statdata); break;
          case REQ_LSTAT:     req->result = lstat     (req->dataptr, req->statdata); break;
          case REQ_FSTAT:     req->result = fstat     (req->fd     , req->statdata); break;

          case REQ_OPEN:      req->result = open      (req->dataptr, req->fd, req->mode); break;
          case REQ_CLOSE:     req->result = close     (req->fd); break;
          case REQ_UNLINK:    req->result = unlink    (req->dataptr); break;

          case REQ_FSYNC:     req->result = fsync     (req->fd); break;
          case REQ_FDATASYNC: req->result = fdatasync (req->fd); break;

          case REQ_QUIT:
            break;

          default:
            req->result = ENOSYS;
            break;
        }

      req->errorno = errno;

      pthread_mutex_lock (&reslock);

      req->next = 0;

      if (rese)
        {
          rese->next = req;
          rese = req;
        }
      else
        {
          rese = ress = req;

          /* write a dummy byte to the pipe so fh becomes ready */
          write (respipe [1], &respipe, 1);
        }

      pthread_mutex_unlock (&reslock);
    }
  while (type != REQ_QUIT);

  return 0;
}

MODULE = IO::AIO                PACKAGE = IO::AIO

PROTOTYPES: ENABLE

BOOT:
{
        if (pipe (respipe))
          croak ("unable to initialize result pipe");

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

        if (fcntl (respipe [1], 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--;
          }

        while (started > nthreads)
          {
            poll_wait ();
            poll_cb ();
          }
}

int
max_outstanding(nreqs)
        int nreqs
        PROTOTYPE: $
        CODE:
        RETVAL = max_outstanding;
        max_outstanding = nreqs;

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

        Newz (0, req, 1, aio_cb);

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

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

        send_req (req);
}

void
aio_close(fh,callback=&PL_sv_undef)
        SV *    fh
        SV *    callback
        PROTOTYPE: $;$
        ALIAS:
           aio_close     = REQ_CLOSE
           aio_fsync     = REQ_FSYNC
           aio_fdatasync = REQ_FDATASYNC
        CODE:
{
        aio_req req;

        Newz (0, req, 1, aio_cb);

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

        req->type = ix;
        req->fh = newSVsv (fh);
        req->fd = PerlIO_fileno (IoIFP (sv_2io (fh)));
        req->callback = SvREFCNT_inc (callback);

        send_req (req);
}

void
aio_read(fh,offset,length,data,dataoffset,callback=&PL_sv_undef)
        SV *    fh
        UV      offset
        IV      length
        SV *    data
        IV      dataoffset
        SV *    callback
        ALIAS:
           aio_read  = REQ_READ
           aio_write = REQ_WRITE
        PROTOTYPE: $$$$$;$
        CODE:
{
        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 (ix == REQ_WRITE)
          {
            /* 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");

        Newz (0, req, 1, aio_cb);

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

        req->type = ix;
        req->fh = newSVsv (fh);
        req->fd = PerlIO_fileno (ix == REQ_READ ? IoIFP (sv_2io (fh))
                                                : IoOFP (sv_2io (fh)));
        req->offset = offset;
        req->length = length;
        req->data = SvREFCNT_inc (data);
        req->dataptr = (char *)svptr + dataoffset;
        req->callback = SvREFCNT_inc (callback);

        send_req (req);
}

void
aio_readahead(fh,offset,length,callback=&PL_sv_undef)
        SV *    fh
        UV      offset
        IV      length
        SV *    callback
        PROTOTYPE: $$$;$
        CODE:
{
        aio_req req;

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

        Newz (0, req, 1, aio_cb);

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

        req->type = REQ_READAHEAD;
        req->fh = newSVsv (fh);
        req->fd = PerlIO_fileno (IoIFP (sv_2io (fh)));
        req->offset = offset;
        req->length = length;
        req->callback = SvREFCNT_inc (callback);

        send_req (req);
}

void
aio_stat(fh_or_path,callback=&PL_sv_undef)
        SV *            fh_or_path
        SV *            callback
        ALIAS:
           aio_stat  = REQ_STAT
           aio_lstat = REQ_LSTAT
        CODE:
{
        aio_req req;

        Newz (0, req, 1, aio_cb);

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

        New (0, req->statdata, 1, Stat_t);

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

        if (SvPOK (fh_or_path))
          {
            req->type = ix;
            req->data = newSVsv (fh_or_path);
            req->dataptr = SvPV_nolen (req->data);
          }
        else
          {
            req->type = REQ_FSTAT;
            req->fh = newSVsv (fh_or_path);
            req->fd = PerlIO_fileno (IoIFP (sv_2io (fh_or_path)));
          }

        req->callback = SvREFCNT_inc (callback);

        send_req (req);
}

void
aio_unlink(pathname,callback=&PL_sv_undef)
        SV * pathname
        SV * callback
        CODE:
{
        aio_req req;
        
        Newz (0, req, 1, aio_cb);
        
        if (!req)
          croak ("out of memory during aio_req allocation");
        
        req->type = REQ_UNLINK;
        req->data = newSVsv (pathname);
        req->dataptr = SvPV_nolen (req->data);
        req->callback = SvREFCNT_inc (callback);
        
        send_req (req);
}

void
flush()
        PROTOTYPE:
        CODE:
        while (nreqs)
          {
            poll_wait ();
            poll_cb ();
          }

void
poll()
        PROTOTYPE:
        CODE:
        if (nreqs)
          {
            poll_wait ();
            poll_cb ();
          }

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

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

void
poll_wait()
        PROTOTYPE:
        CODE:
        if (nreqs)
          poll_wait ();

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

Revision:	1.14
Committed:	Sat Jul 23 18:15:36 2005 UTC (18 years, 9 months ago) by root
Branch:	MAIN
Changes since 1.13:	+0 -3 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	#include "perl.h"
2			#include "XSUB.h"
3
4			#include <sys/types.h>
5			#include <sys/stat.h>
6	root	1.10
7	root	1.1	#include <unistd.h>
8			#include <fcntl.h>
9			#include <signal.h>
10			#include <sched.h>
11	root	1.10	#if __linux
12			#include <sys/syscall.h>
13			#endif
14	root	1.1
15			#include <pthread.h>
16
17			typedef void InputStream; / hack, but 5.6.1 is simply toooo old ;) */
18			typedef void OutputStream; / hack, but 5.6.1 is simply toooo old ;) */
19			typedef void InOutStream; / hack, but 5.6.1 is simply toooo old ;) */
20
21	root	1.4	#if __ia64
22			# define STACKSIZE 65536
23	root	1.1	#else
24	root	1.4	# define STACKSIZE 4096
25	root	1.1	#endif
26
27			enum {
28			REQ_QUIT,
29			REQ_OPEN, REQ_CLOSE,
30			REQ_READ, REQ_WRITE, REQ_READAHEAD,
31			REQ_STAT, REQ_LSTAT, REQ_FSTAT, REQ_UNLINK,
32			REQ_FSYNC, REQ_FDATASYNC,
33			};
34
35			typedef struct aio_cb {
36	root	1.3	struct aio_cb *volatile next;
37	root	1.1
38			int type;
39
40			int fd;
41			off_t offset;
42			size_t length;
43			ssize_t result;
44			mode_t mode; /* open */
45			int errorno;
46	root	1.13	SV data, callback, *fh;
47	root	1.1	void *dataptr;
48			STRLEN dataoffset;
49
50			Stat_t *statdata;
51			} aio_cb;
52
53			typedef aio_cb *aio_req;
54
55			static int started;
56	root	1.11	static volatile int nreqs;
57	root	1.4	static int max_outstanding = 1<<30;
58	root	1.3	static int respipe [2];
59	root	1.1
60	root	1.3	static pthread_mutex_t reslock = PTHREAD_MUTEX_INITIALIZER;
61			static pthread_mutex_t reqlock = PTHREAD_MUTEX_INITIALIZER;
62			static pthread_cond_t reqwait = PTHREAD_COND_INITIALIZER;
63
64			static volatile aio_req reqs, reqe; /* queue start, queue end */
65			static volatile aio_req ress, rese; /* queue start, queue end */
66	root	1.1
67			static void
68			poll_wait ()
69			{
70	root	1.11	if (nreqs && !ress)
71			{
72			fd_set rfd;
73			FD_ZERO(&rfd);
74			FD_SET(respipe [0], &rfd);
75	root	1.3
76	root	1.11	select (respipe [0] + 1, &rfd, 0, 0, 0);
77			}
78	root	1.1	}
79
80			static int
81	root	1.5	poll_cb ()
82	root	1.1	{
83			dSP;
84			int count = 0;
85	root	1.11	aio_req req, prv;
86
87			pthread_mutex_lock (&reslock);
88
89	root	1.3	{
90	root	1.11	/* read any signals sent by the worker threads */
91	root	1.3	char buf [32];
92			while (read (respipe [0], buf, 32) > 0)
93			;
94			}
95	root	1.1
96	root	1.11	req = ress;
97			ress = rese = 0;
98	root	1.3
99	root	1.11	pthread_mutex_unlock (&reslock);
100	root	1.3
101	root	1.11	while (req)
102			{
103	root	1.1	nreqs--;
104
105			if (req->type == REQ_QUIT)
106			started--;
107			else
108			{
109			int errorno = errno;
110			errno = req->errorno;
111
112			if (req->type == REQ_READ)
113			SvCUR_set (req->data, req->dataoffset
114			+ req->result > 0 ? req->result : 0);
115
116			if (req->data)
117			SvREFCNT_dec (req->data);
118
119	root	1.13	if (req->fh)
120			SvREFCNT_dec (req->fh);
121
122	root	1.1	if (req->type == REQ_STAT \|\| req->type == REQ_LSTAT \|\| req->type == REQ_FSTAT)
123			{
124			PL_laststype = req->type == REQ_LSTAT ? OP_LSTAT : OP_STAT;
125			PL_laststatval = req->result;
126			PL_statcache = *(req->statdata);
127
128			Safefree (req->statdata);
129			}
130
131	root	1.13	ENTER;
132	root	1.1	PUSHMARK (SP);
133			XPUSHs (sv_2mortal (newSViv (req->result)));
134	root	1.2
135			if (req->type == REQ_OPEN)
136			{
137			/* convert fd to fh */
138			SV *fh;
139
140			PUTBACK;
141			call_pv ("IO::AIO::_fd2fh", G_SCALAR \| G_EVAL);
142			SPAGAIN;
143
144	root	1.13	fh = SvREFCNT_inc (POPs);
145	root	1.2
146			PUSHMARK (SP);
147	root	1.13	XPUSHs (sv_2mortal (fh));
148	root	1.2	}
149
150	root	1.8	if (SvOK (req->callback))
151			{
152			PUTBACK;
153			call_sv (req->callback, G_VOID \| G_EVAL);
154			SPAGAIN;
155			}
156	root	1.13
157			LEAVE;
158	root	1.1
159			if (req->callback)
160			SvREFCNT_dec (req->callback);
161
162			errno = errorno;
163			count++;
164			}
165
166	root	1.11	prv = req;
167			req = req->next;
168			Safefree (prv);
169
170			/* TODO: croak on errors? */
171	root	1.1	}
172
173			return count;
174			}
175
176	root	1.4	static void aio_proc(void arg);
177
178			static void
179			start_thread (void)
180			{
181			sigset_t fullsigset, oldsigset;
182			pthread_t tid;
183			pthread_attr_t attr;
184
185			pthread_attr_init (&attr);
186			pthread_attr_setstacksize (&attr, STACKSIZE);
187			pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
188
189			sigfillset (&fullsigset);
190			sigprocmask (SIG_SETMASK, &fullsigset, &oldsigset);
191
192			if (pthread_create (&tid, &attr, aio_proc, 0) == 0)
193			started++;
194
195			sigprocmask (SIG_SETMASK, &oldsigset, 0);
196			}
197
198			static void
199			send_req (aio_req req)
200			{
201			nreqs++;
202
203			pthread_mutex_lock (&reqlock);
204
205			req->next = 0;
206
207			if (reqe)
208			{
209			reqe->next = req;
210			reqe = req;
211			}
212			else
213			reqe = reqs = req;
214
215			pthread_cond_signal (&reqwait);
216			pthread_mutex_unlock (&reqlock);
217
218			while (nreqs > max_outstanding)
219			{
220			poll_wait ();
221			poll_cb ();
222			}
223			}
224
225			static void
226			end_thread (void)
227			{
228			aio_req req;
229			New (0, req, 1, aio_cb);
230			req->type = REQ_QUIT;
231
232			send_req (req);
233			}
234
235	root	1.1	static void *
236			aio_proc (void *thr_arg)
237			{
238			aio_req req;
239	root	1.3	int type;
240	root	1.1
241	root	1.3	do
242	root	1.1	{
243	root	1.3	pthread_mutex_lock (&reqlock);
244
245			for (;;)
246			{
247			req = reqs;
248
249			if (reqs)
250			{
251			reqs = reqs->next;
252			if (!reqs) reqe = 0;
253			}
254
255			if (req)
256			break;
257
258			pthread_cond_wait (&reqwait, &reqlock);
259			}
260
261			pthread_mutex_unlock (&reqlock);
262
263	root	1.1	errno = 0; /* strictly unnecessary */
264
265	root	1.3	type = req->type;
266
267			switch (type)
268	root	1.1	{
269	root	1.10	case REQ_READ: req->result = pread (req->fd, req->dataptr, req->length, req->offset); break;
270			case REQ_WRITE: req->result = pwrite (req->fd, req->dataptr, req->length, req->offset); break;
271	root	1.1	#if SYS_readahead
272			case REQ_READAHEAD: req->result = readahead (req->fd, req->offset, req->length); break;
273			#else
274			case REQ_READAHEAD: req->result = -1; errno = ENOSYS; break;
275			#endif
276
277			case REQ_STAT: req->result = stat (req->dataptr, req->statdata); break;
278			case REQ_LSTAT: req->result = lstat (req->dataptr, req->statdata); break;
279			case REQ_FSTAT: req->result = fstat (req->fd , req->statdata); break;
280
281			case REQ_OPEN: req->result = open (req->dataptr, req->fd, req->mode); break;
282			case REQ_CLOSE: req->result = close (req->fd); break;
283			case REQ_UNLINK: req->result = unlink (req->dataptr); break;
284
285			case REQ_FSYNC: req->result = fsync (req->fd); break;
286			case REQ_FDATASYNC: req->result = fdatasync (req->fd); break;
287
288			case REQ_QUIT:
289	root	1.3	break;
290	root	1.1
291			default:
292			req->result = ENOSYS;
293			break;
294			}
295
296			req->errorno = errno;
297	root	1.3
298			pthread_mutex_lock (&reslock);
299
300			req->next = 0;
301
302			if (rese)
303			{
304			rese->next = req;
305			rese = req;
306			}
307			else
308			{
309			rese = ress = req;
310
311			/* write a dummy byte to the pipe so fh becomes ready */
312			write (respipe [1], &respipe, 1);
313			}
314
315			pthread_mutex_unlock (&reslock);
316	root	1.1	}
317	root	1.3	while (type != REQ_QUIT);
318	root	1.1
319			return 0;
320			}
321
322			MODULE = IO::AIO PACKAGE = IO::AIO
323
324	root	1.8	PROTOTYPES: ENABLE
325
326	root	1.1	BOOT:
327			{
328	root	1.3	if (pipe (respipe))
329			croak ("unable to initialize result pipe");
330	root	1.1
331	root	1.3	if (fcntl (respipe [0], F_SETFL, O_NONBLOCK))
332	root	1.1	croak ("cannot set result pipe to nonblocking mode");
333
334	root	1.3	if (fcntl (respipe [1], F_SETFL, O_NONBLOCK))
335	root	1.1	croak ("cannot set result pipe to nonblocking mode");
336			}
337
338			void
339			min_parallel(nthreads)
340			int nthreads
341			PROTOTYPE: $
342			CODE:
343			while (nthreads > started)
344			start_thread ();
345
346			void
347			max_parallel(nthreads)
348			int nthreads
349			PROTOTYPE: $
350			CODE:
351			{
352			int cur = started;
353			while (cur > nthreads)
354			{
355			end_thread ();
356			cur--;
357			}
358
359			while (started > nthreads)
360			{
361			poll_wait ();
362	root	1.5	poll_cb ();
363	root	1.1	}
364			}
365
366	root	1.4	int
367			max_outstanding(nreqs)
368			int nreqs
369			PROTOTYPE: $
370			CODE:
371			RETVAL = max_outstanding;
372			max_outstanding = nreqs;
373
374	root	1.1	void
375	root	1.8	aio_open(pathname,flags,mode,callback=&PL_sv_undef)
376	root	1.1	SV * pathname
377			int flags
378			int mode
379			SV * callback
380	root	1.8	PROTOTYPE: $$$;$
381	root	1.1	CODE:
382			{
383			aio_req req;
384
385			Newz (0, req, 1, aio_cb);
386
387			if (!req)
388			croak ("out of memory during aio_req allocation");
389
390			req->type = REQ_OPEN;
391			req->data = newSVsv (pathname);
392			req->dataptr = SvPV_nolen (req->data);
393			req->fd = flags;
394			req->mode = mode;
395			req->callback = SvREFCNT_inc (callback);
396
397			send_req (req);
398			}
399
400			void
401	root	1.8	aio_close(fh,callback=&PL_sv_undef)
402	root	1.13	SV * fh
403			SV * callback
404	root	1.8	PROTOTYPE: $;$
405	root	1.1	ALIAS:
406			aio_close = REQ_CLOSE
407			aio_fsync = REQ_FSYNC
408			aio_fdatasync = REQ_FDATASYNC
409			CODE:
410			{
411			aio_req req;
412
413			Newz (0, req, 1, aio_cb);
414
415			if (!req)
416			croak ("out of memory during aio_req allocation");
417
418			req->type = ix;
419	root	1.13	req->fh = newSVsv (fh);
420			req->fd = PerlIO_fileno (IoIFP (sv_2io (fh)));
421	root	1.1	req->callback = SvREFCNT_inc (callback);
422
423			send_req (req);
424			}
425
426			void
427	root	1.8	aio_read(fh,offset,length,data,dataoffset,callback=&PL_sv_undef)
428	root	1.13	SV * fh
429			UV offset
430			IV length
431			SV * data
432			IV dataoffset
433			SV * callback
434			ALIAS:
435			aio_read = REQ_READ
436			aio_write = REQ_WRITE
437	root	1.8	PROTOTYPE: $$$$$;$
438	root	1.1	CODE:
439	root	1.13	{
440			aio_req req;
441			STRLEN svlen;
442			char *svptr = SvPV (data, svlen);
443
444			SvUPGRADE (data, SVt_PV);
445			SvPOK_on (data);
446	root	1.1
447	root	1.13	if (dataoffset < 0)
448			dataoffset += svlen;
449
450			if (dataoffset < 0 \|\| dataoffset > svlen)
451			croak ("data offset outside of string");
452
453			if (ix == REQ_WRITE)
454			{
455			/* write: check length and adjust. */
456			if (length < 0 \|\| length + dataoffset > svlen)
457			length = svlen - dataoffset;
458			}
459			else
460			{
461			/* read: grow scalar as necessary */
462			svptr = SvGROW (data, length + dataoffset);
463			}
464
465			if (length < 0)
466			croak ("length must not be negative");
467
468			Newz (0, req, 1, aio_cb);
469
470			if (!req)
471			croak ("out of memory during aio_req allocation");
472
473			req->type = ix;
474			req->fh = newSVsv (fh);
475			req->fd = PerlIO_fileno (ix == REQ_READ ? IoIFP (sv_2io (fh))
476			: IoOFP (sv_2io (fh)));
477			req->offset = offset;
478			req->length = length;
479			req->data = SvREFCNT_inc (data);
480			req->dataptr = (char *)svptr + dataoffset;
481			req->callback = SvREFCNT_inc (callback);
482
483			send_req (req);
484			}
485	root	1.1
486			void
487	root	1.8	aio_readahead(fh,offset,length,callback=&PL_sv_undef)
488	root	1.13	SV * fh
489			UV offset
490			IV length
491			SV * callback
492	root	1.8	PROTOTYPE: $$$;$
493	root	1.1	CODE:
494			{
495			aio_req req;
496
497			if (length < 0)
498			croak ("length must not be negative");
499
500			Newz (0, req, 1, aio_cb);
501
502			if (!req)
503			croak ("out of memory during aio_req allocation");
504
505			req->type = REQ_READAHEAD;
506	root	1.13	req->fh = newSVsv (fh);
507			req->fd = PerlIO_fileno (IoIFP (sv_2io (fh)));
508	root	1.1	req->offset = offset;
509			req->length = length;
510			req->callback = SvREFCNT_inc (callback);
511
512			send_req (req);
513			}
514
515			void
516	root	1.8	aio_stat(fh_or_path,callback=&PL_sv_undef)
517	root	1.1	SV * fh_or_path
518			SV * callback
519			ALIAS:
520	root	1.8	aio_stat = REQ_STAT
521			aio_lstat = REQ_LSTAT
522	root	1.1	CODE:
523			{
524			aio_req req;
525
526			Newz (0, req, 1, aio_cb);
527
528			if (!req)
529			croak ("out of memory during aio_req allocation");
530
531			New (0, req->statdata, 1, Stat_t);
532
533			if (!req->statdata)
534			croak ("out of memory during aio_req->statdata allocation");
535
536			if (SvPOK (fh_or_path))
537			{
538	root	1.8	req->type = ix;
539	root	1.1	req->data = newSVsv (fh_or_path);
540			req->dataptr = SvPV_nolen (req->data);
541			}
542			else
543			{
544			req->type = REQ_FSTAT;
545	root	1.13	req->fh = newSVsv (fh_or_path);
546	root	1.1	req->fd = PerlIO_fileno (IoIFP (sv_2io (fh_or_path)));
547			}
548
549			req->callback = SvREFCNT_inc (callback);
550
551			send_req (req);
552			}
553
554			void
555	root	1.8	aio_unlink(pathname,callback=&PL_sv_undef)
556	root	1.1	SV * pathname
557			SV * callback
558			CODE:
559			{
560			aio_req req;
561
562			Newz (0, req, 1, aio_cb);
563
564			if (!req)
565			croak ("out of memory during aio_req allocation");
566
567			req->type = REQ_UNLINK;
568			req->data = newSVsv (pathname);
569			req->dataptr = SvPV_nolen (req->data);
570			req->callback = SvREFCNT_inc (callback);
571
572			send_req (req);
573			}
574
575	root	1.6	void
576			flush()
577			PROTOTYPE:
578			CODE:
579			while (nreqs)
580			{
581			poll_wait ();
582			poll_cb ();
583			}
584
585	root	1.7	void
586			poll()
587			PROTOTYPE:
588			CODE:
589			if (nreqs)
590			{
591			poll_wait ();
592			poll_cb ();
593			}
594
595	root	1.1	int
596			poll_fileno()
597			PROTOTYPE:
598			CODE:
599	root	1.3	RETVAL = respipe [0];
600	root	1.1	OUTPUT:
601			RETVAL
602
603			int
604			poll_cb(...)
605			PROTOTYPE:
606			CODE:
607	root	1.5	RETVAL = poll_cb ();
608	root	1.1	OUTPUT:
609			RETVAL
610
611			void
612			poll_wait()
613			PROTOTYPE:
614			CODE:
615	root	1.3	if (nreqs)
616			poll_wait ();
617	root	1.1
618			int
619			nreqs()
620			PROTOTYPE:
621			CODE:
622			RETVAL = nreqs;
623			OUTPUT:
624			RETVAL
625