IO-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>
#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:	1.15
Committed:	Sat Jul 23 18:19:56 2005 UTC (18 years, 9 months ago) by root
Branch:	MAIN
Changes since 1.14:	+1 -0 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.15	#include "EXTERN.h"
2	root	1.1	#include "perl.h"
3			#include "XSUB.h"
4
5			#include <sys/types.h>
6			#include <sys/stat.h>
7	root	1.10
8	root	1.1	#include <unistd.h>
9			#include <fcntl.h>
10			#include <signal.h>
11			#include <sched.h>
12	root	1.10	#if __linux
13			#include <sys/syscall.h>
14			#endif
15	root	1.1
16			#include <pthread.h>
17
18			typedef void InputStream; / hack, but 5.6.1 is simply toooo old ;) */
19			typedef void OutputStream; / hack, but 5.6.1 is simply toooo old ;) */
20			typedef void InOutStream; / hack, but 5.6.1 is simply toooo old ;) */
21
22	root	1.4	#if __ia64
23			# define STACKSIZE 65536
24	root	1.1	#else
25	root	1.4	# define STACKSIZE 4096
26	root	1.1	#endif
27
28			enum {
29			REQ_QUIT,
30			REQ_OPEN, REQ_CLOSE,
31			REQ_READ, REQ_WRITE, REQ_READAHEAD,
32			REQ_STAT, REQ_LSTAT, REQ_FSTAT, REQ_UNLINK,
33			REQ_FSYNC, REQ_FDATASYNC,
34			};
35
36			typedef struct aio_cb {
37	root	1.3	struct aio_cb *volatile next;
38	root	1.1
39			int type;
40
41			int fd;
42			off_t offset;
43			size_t length;
44			ssize_t result;
45			mode_t mode; /* open */
46			int errorno;
47	root	1.13	SV data, callback, *fh;
48	root	1.1	void *dataptr;
49			STRLEN dataoffset;
50
51			Stat_t *statdata;
52			} aio_cb;
53
54			typedef aio_cb *aio_req;
55
56			static int started;
57	root	1.11	static volatile int nreqs;
58	root	1.4	static int max_outstanding = 1<<30;
59	root	1.3	static int respipe [2];
60	root	1.1
61	root	1.3	static pthread_mutex_t reslock = PTHREAD_MUTEX_INITIALIZER;
62			static pthread_mutex_t reqlock = PTHREAD_MUTEX_INITIALIZER;
63			static pthread_cond_t reqwait = PTHREAD_COND_INITIALIZER;
64
65			static volatile aio_req reqs, reqe; /* queue start, queue end */
66			static volatile aio_req ress, rese; /* queue start, queue end */
67	root	1.1
68			static void
69			poll_wait ()
70			{
71	root	1.11	if (nreqs && !ress)
72			{
73			fd_set rfd;
74			FD_ZERO(&rfd);
75			FD_SET(respipe [0], &rfd);
76	root	1.3
77	root	1.11	select (respipe [0] + 1, &rfd, 0, 0, 0);
78			}
79	root	1.1	}
80
81			static int
82	root	1.5	poll_cb ()
83	root	1.1	{
84			dSP;
85			int count = 0;
86	root	1.11	aio_req req, prv;
87
88			pthread_mutex_lock (&reslock);
89
90	root	1.3	{
91	root	1.11	/* read any signals sent by the worker threads */
92	root	1.3	char buf [32];
93			while (read (respipe [0], buf, 32) > 0)
94			;
95			}
96	root	1.1
97	root	1.11	req = ress;
98			ress = rese = 0;
99	root	1.3
100	root	1.11	pthread_mutex_unlock (&reslock);
101	root	1.3
102	root	1.11	while (req)
103			{
104	root	1.1	nreqs--;
105
106			if (req->type == REQ_QUIT)
107			started--;
108			else
109			{
110			int errorno = errno;
111			errno = req->errorno;
112
113			if (req->type == REQ_READ)
114			SvCUR_set (req->data, req->dataoffset
115			+ req->result > 0 ? req->result : 0);
116
117			if (req->data)
118			SvREFCNT_dec (req->data);
119
120	root	1.13	if (req->fh)
121			SvREFCNT_dec (req->fh);
122
123	root	1.1	if (req->type == REQ_STAT \|\| req->type == REQ_LSTAT \|\| req->type == REQ_FSTAT)
124			{
125			PL_laststype = req->type == REQ_LSTAT ? OP_LSTAT : OP_STAT;
126			PL_laststatval = req->result;
127			PL_statcache = *(req->statdata);
128
129			Safefree (req->statdata);
130			}
131
132	root	1.13	ENTER;
133	root	1.1	PUSHMARK (SP);
134			XPUSHs (sv_2mortal (newSViv (req->result)));
135	root	1.2
136			if (req->type == REQ_OPEN)
137			{
138			/* convert fd to fh */
139			SV *fh;
140
141			PUTBACK;
142			call_pv ("IO::AIO::_fd2fh", G_SCALAR \| G_EVAL);
143			SPAGAIN;
144
145	root	1.13	fh = SvREFCNT_inc (POPs);
146	root	1.2
147			PUSHMARK (SP);
148	root	1.13	XPUSHs (sv_2mortal (fh));
149	root	1.2	}
150
151	root	1.8	if (SvOK (req->callback))
152			{
153			PUTBACK;
154			call_sv (req->callback, G_VOID \| G_EVAL);
155			SPAGAIN;
156			}
157	root	1.13
158			LEAVE;
159	root	1.1
160			if (req->callback)
161			SvREFCNT_dec (req->callback);
162
163			errno = errorno;
164			count++;
165			}
166
167	root	1.11	prv = req;
168			req = req->next;
169			Safefree (prv);
170
171			/* TODO: croak on errors? */
172	root	1.1	}
173
174			return count;
175			}
176
177	root	1.4	static void aio_proc(void arg);
178
179			static void
180			start_thread (void)
181			{
182			sigset_t fullsigset, oldsigset;
183			pthread_t tid;
184			pthread_attr_t attr;
185
186			pthread_attr_init (&attr);
187			pthread_attr_setstacksize (&attr, STACKSIZE);
188			pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
189
190			sigfillset (&fullsigset);
191			sigprocmask (SIG_SETMASK, &fullsigset, &oldsigset);
192
193			if (pthread_create (&tid, &attr, aio_proc, 0) == 0)
194			started++;
195
196			sigprocmask (SIG_SETMASK, &oldsigset, 0);
197			}
198
199			static void
200			send_req (aio_req req)
201			{
202			nreqs++;
203
204			pthread_mutex_lock (&reqlock);
205
206			req->next = 0;
207
208			if (reqe)
209			{
210			reqe->next = req;
211			reqe = req;
212			}
213			else
214			reqe = reqs = req;
215
216			pthread_cond_signal (&reqwait);
217			pthread_mutex_unlock (&reqlock);
218
219			while (nreqs > max_outstanding)
220			{
221			poll_wait ();
222			poll_cb ();
223			}
224			}
225
226			static void
227			end_thread (void)
228			{
229			aio_req req;
230			New (0, req, 1, aio_cb);
231			req->type = REQ_QUIT;
232
233			send_req (req);
234			}
235
236	root	1.1	static void *
237			aio_proc (void *thr_arg)
238			{
239			aio_req req;
240	root	1.3	int type;
241	root	1.1
242	root	1.3	do
243	root	1.1	{
244	root	1.3	pthread_mutex_lock (&reqlock);
245
246			for (;;)
247			{
248			req = reqs;
249
250			if (reqs)
251			{
252			reqs = reqs->next;
253			if (!reqs) reqe = 0;
254			}
255
256			if (req)
257			break;
258
259			pthread_cond_wait (&reqwait, &reqlock);
260			}
261
262			pthread_mutex_unlock (&reqlock);
263
264	root	1.1	errno = 0; /* strictly unnecessary */
265
266	root	1.3	type = req->type;
267
268			switch (type)
269	root	1.1	{
270	root	1.10	case REQ_READ: req->result = pread (req->fd, req->dataptr, req->length, req->offset); break;
271			case REQ_WRITE: req->result = pwrite (req->fd, req->dataptr, req->length, req->offset); break;
272	root	1.1	#if SYS_readahead
273			case REQ_READAHEAD: req->result = readahead (req->fd, req->offset, req->length); break;
274			#else
275			case REQ_READAHEAD: req->result = -1; errno = ENOSYS; break;
276			#endif
277
278			case REQ_STAT: req->result = stat (req->dataptr, req->statdata); break;
279			case REQ_LSTAT: req->result = lstat (req->dataptr, req->statdata); break;
280			case REQ_FSTAT: req->result = fstat (req->fd , req->statdata); break;
281
282			case REQ_OPEN: req->result = open (req->dataptr, req->fd, req->mode); break;
283			case REQ_CLOSE: req->result = close (req->fd); break;
284			case REQ_UNLINK: req->result = unlink (req->dataptr); break;
285
286			case REQ_FSYNC: req->result = fsync (req->fd); break;
287			case REQ_FDATASYNC: req->result = fdatasync (req->fd); break;
288
289			case REQ_QUIT:
290	root	1.3	break;
291	root	1.1
292			default:
293			req->result = ENOSYS;
294			break;
295			}
296
297			req->errorno = errno;
298	root	1.3
299			pthread_mutex_lock (&reslock);
300
301			req->next = 0;
302
303			if (rese)
304			{
305			rese->next = req;
306			rese = req;
307			}
308			else
309			{
310			rese = ress = req;
311
312			/* write a dummy byte to the pipe so fh becomes ready */
313			write (respipe [1], &respipe, 1);
314			}
315
316			pthread_mutex_unlock (&reslock);
317	root	1.1	}
318	root	1.3	while (type != REQ_QUIT);
319	root	1.1
320			return 0;
321			}
322
323			MODULE = IO::AIO PACKAGE = IO::AIO
324
325	root	1.8	PROTOTYPES: ENABLE
326
327	root	1.1	BOOT:
328			{
329	root	1.3	if (pipe (respipe))
330			croak ("unable to initialize result pipe");
331	root	1.1
332	root	1.3	if (fcntl (respipe [0], F_SETFL, O_NONBLOCK))
333	root	1.1	croak ("cannot set result pipe to nonblocking mode");
334
335	root	1.3	if (fcntl (respipe [1], F_SETFL, O_NONBLOCK))
336	root	1.1	croak ("cannot set result pipe to nonblocking mode");
337			}
338
339			void
340			min_parallel(nthreads)
341			int nthreads
342			PROTOTYPE: $
343			CODE:
344			while (nthreads > started)
345			start_thread ();
346
347			void
348			max_parallel(nthreads)
349			int nthreads
350			PROTOTYPE: $
351			CODE:
352			{
353			int cur = started;
354			while (cur > nthreads)
355			{
356			end_thread ();
357			cur--;
358			}
359
360			while (started > nthreads)
361			{
362			poll_wait ();
363	root	1.5	poll_cb ();
364	root	1.1	}
365			}
366
367	root	1.4	int
368			max_outstanding(nreqs)
369			int nreqs
370			PROTOTYPE: $
371			CODE:
372			RETVAL = max_outstanding;
373			max_outstanding = nreqs;
374
375	root	1.1	void
376	root	1.8	aio_open(pathname,flags,mode,callback=&PL_sv_undef)
377	root	1.1	SV * pathname
378			int flags
379			int mode
380			SV * callback
381	root	1.8	PROTOTYPE: $$$;$
382	root	1.1	CODE:
383			{
384			aio_req req;
385
386			Newz (0, req, 1, aio_cb);
387
388			if (!req)
389			croak ("out of memory during aio_req allocation");
390
391			req->type = REQ_OPEN;
392			req->data = newSVsv (pathname);
393			req->dataptr = SvPV_nolen (req->data);
394			req->fd = flags;
395			req->mode = mode;
396			req->callback = SvREFCNT_inc (callback);
397
398			send_req (req);
399			}
400
401			void
402	root	1.8	aio_close(fh,callback=&PL_sv_undef)
403	root	1.13	SV * fh
404			SV * callback
405	root	1.8	PROTOTYPE: $;$
406	root	1.1	ALIAS:
407			aio_close = REQ_CLOSE
408			aio_fsync = REQ_FSYNC
409			aio_fdatasync = REQ_FDATASYNC
410			CODE:
411			{
412			aio_req req;
413
414			Newz (0, req, 1, aio_cb);
415
416			if (!req)
417			croak ("out of memory during aio_req allocation");
418
419			req->type = ix;
420	root	1.13	req->fh = newSVsv (fh);
421			req->fd = PerlIO_fileno (IoIFP (sv_2io (fh)));
422	root	1.1	req->callback = SvREFCNT_inc (callback);
423
424			send_req (req);
425			}
426
427			void
428	root	1.8	aio_read(fh,offset,length,data,dataoffset,callback=&PL_sv_undef)
429	root	1.13	SV * fh
430			UV offset
431			IV length
432			SV * data
433			IV dataoffset
434			SV * callback
435			ALIAS:
436			aio_read = REQ_READ
437			aio_write = REQ_WRITE
438	root	1.8	PROTOTYPE: $$$$$;$
439	root	1.1	CODE:
440	root	1.13	{
441			aio_req req;
442			STRLEN svlen;
443			char *svptr = SvPV (data, svlen);
444
445			SvUPGRADE (data, SVt_PV);
446			SvPOK_on (data);
447	root	1.1
448	root	1.13	if (dataoffset < 0)
449			dataoffset += svlen;
450
451			if (dataoffset < 0 \|\| dataoffset > svlen)
452			croak ("data offset outside of string");
453
454			if (ix == REQ_WRITE)
455			{
456			/* write: check length and adjust. */
457			if (length < 0 \|\| length + dataoffset > svlen)
458			length = svlen - dataoffset;
459			}
460			else
461			{
462			/* read: grow scalar as necessary */
463			svptr = SvGROW (data, length + dataoffset);
464			}
465
466			if (length < 0)
467			croak ("length must not be negative");
468
469			Newz (0, req, 1, aio_cb);
470
471			if (!req)
472			croak ("out of memory during aio_req allocation");
473
474			req->type = ix;
475			req->fh = newSVsv (fh);
476			req->fd = PerlIO_fileno (ix == REQ_READ ? IoIFP (sv_2io (fh))
477			: IoOFP (sv_2io (fh)));
478			req->offset = offset;
479			req->length = length;
480			req->data = SvREFCNT_inc (data);
481			req->dataptr = (char *)svptr + dataoffset;
482			req->callback = SvREFCNT_inc (callback);
483
484			send_req (req);
485			}
486	root	1.1
487			void
488	root	1.8	aio_readahead(fh,offset,length,callback=&PL_sv_undef)
489	root	1.13	SV * fh
490			UV offset
491			IV length
492			SV * callback
493	root	1.8	PROTOTYPE: $$$;$
494	root	1.1	CODE:
495			{
496			aio_req req;
497
498			if (length < 0)
499			croak ("length must not be negative");
500
501			Newz (0, req, 1, aio_cb);
502
503			if (!req)
504			croak ("out of memory during aio_req allocation");
505
506			req->type = REQ_READAHEAD;
507	root	1.13	req->fh = newSVsv (fh);
508			req->fd = PerlIO_fileno (IoIFP (sv_2io (fh)));
509	root	1.1	req->offset = offset;
510			req->length = length;
511			req->callback = SvREFCNT_inc (callback);
512
513			send_req (req);
514			}
515
516			void
517	root	1.8	aio_stat(fh_or_path,callback=&PL_sv_undef)
518	root	1.1	SV * fh_or_path
519			SV * callback
520			ALIAS:
521	root	1.8	aio_stat = REQ_STAT
522			aio_lstat = REQ_LSTAT
523	root	1.1	CODE:
524			{
525			aio_req req;
526
527			Newz (0, req, 1, aio_cb);
528
529			if (!req)
530			croak ("out of memory during aio_req allocation");
531
532			New (0, req->statdata, 1, Stat_t);
533
534			if (!req->statdata)
535			croak ("out of memory during aio_req->statdata allocation");
536
537			if (SvPOK (fh_or_path))
538			{
539	root	1.8	req->type = ix;
540	root	1.1	req->data = newSVsv (fh_or_path);
541			req->dataptr = SvPV_nolen (req->data);
542			}
543			else
544			{
545			req->type = REQ_FSTAT;
546	root	1.13	req->fh = newSVsv (fh_or_path);
547	root	1.1	req->fd = PerlIO_fileno (IoIFP (sv_2io (fh_or_path)));
548			}
549
550			req->callback = SvREFCNT_inc (callback);
551
552			send_req (req);
553			}
554
555			void
556	root	1.8	aio_unlink(pathname,callback=&PL_sv_undef)
557	root	1.1	SV * pathname
558			SV * callback
559			CODE:
560			{
561			aio_req req;
562
563			Newz (0, req, 1, aio_cb);
564
565			if (!req)
566			croak ("out of memory during aio_req allocation");
567
568			req->type = REQ_UNLINK;
569			req->data = newSVsv (pathname);
570			req->dataptr = SvPV_nolen (req->data);
571			req->callback = SvREFCNT_inc (callback);
572
573			send_req (req);
574			}
575
576	root	1.6	void
577			flush()
578			PROTOTYPE:
579			CODE:
580			while (nreqs)
581			{
582			poll_wait ();
583			poll_cb ();
584			}
585
586	root	1.7	void
587			poll()
588			PROTOTYPE:
589			CODE:
590			if (nreqs)
591			{
592			poll_wait ();
593			poll_cb ();
594			}
595
596	root	1.1	int
597			poll_fileno()
598			PROTOTYPE:
599			CODE:
600	root	1.3	RETVAL = respipe [0];
601	root	1.1	OUTPUT:
602			RETVAL
603
604			int
605			poll_cb(...)
606			PROTOTYPE:
607			CODE:
608	root	1.5	RETVAL = poll_cb ();
609	root	1.1	OUTPUT:
610			RETVAL
611
612			void
613			poll_wait()
614			PROTOTYPE:
615			CODE:
616	root	1.3	if (nreqs)
617			poll_wait ();
618	root	1.1
619			int
620			nreqs()
621			PROTOTYPE:
622			CODE:
623			RETVAL = nreqs;
624			OUTPUT:
625			RETVAL
626