IO-AIO/AIO.xs

#define _REENTRANT 1
#include <errno.h>

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

#include "autoconf/config.h"

#include <sys/types.h>
#include <sys/stat.h>

#include <unistd.h>
#include <fcntl.h>
#include <signal.h>
#include <sched.h>

#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);
}

/* work around various missing functions */

#if !HAVE_PREADWRITE
# define pread  aio_pread
# define pwrite aio_pwrite

/*
 * make our pread/pwrite safe against themselves, but not against
 * normal read/write by using a mutex. slows down execution a lot,
 * but that's your problem, not mine.
 */
static pthread_mutex_t iolock = PTHREAD_MUTEX_INITIALIZER;

static ssize_t
pread (int fd, void *buf, size_t count, off_t offset)
{
  ssize_t res;
  off_t ooffset;

  pthread_mutex_lock (&iolock);
  ooffset = lseek (fd, 0, SEEK_CUR);
  lseek (fd, offset, SEEK_SET);
  res = read (fd, buf, count);
  lseek (fd, ooffset, SEEK_SET);
  pthread_mutex_unlock (&iolock);

  return res;
}

static ssize_t
pwrite (int fd, void *buf, size_t count, off_t offset)
{
  ssize_t res;
  off_t ooffset;

  pthread_mutex_lock (&iolock);
  ooffset = lseek (fd, 0, SEEK_CUR);
  lseek (fd, offset, SEEK_SET);
  res = write (fd, buf, count);
  lseek (fd, offset, SEEK_SET);
  pthread_mutex_unlock (&iolock);

  return res;
}
#endif

#if !HAVE_FDATASYNC
# define fdatasync fsync
#endif

#if !HAVE_READAHEAD
# define readahead aio_readahead

static char readahead_buf[4096];

static ssize_t
readahead (int fd, off_t offset, size_t count)
{
  while (count > 0)
    {
      size_t len = count < sizeof (readahead_buf) ? count : sizeof (readahead_buf);

      pread (fd, readahead_buf, len, offset);
      offset += len;
      count  -= len;
    }

  errno = 0;
}
#endif

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;

          case REQ_READAHEAD: req->result = readahead (req->fd, req->offset, req->length); break;

          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_FDATASYNC: req->result = fdatasync (req->fd); break;
          case REQ_FSYNC:     req->result = fsync     (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:	1.20
Committed:	Sun Jul 31 19:08:39 2005 UTC (18 years, 9 months ago) by root
Branch:	MAIN
Changes since 1.19:	+1 -3 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.20	#define _REENTRANT 1
2	root	1.19	#include <errno.h>
3
4	root	1.15	#include "EXTERN.h"
5	root	1.1	#include "perl.h"
6			#include "XSUB.h"
7
8	root	1.16	#include "autoconf/config.h"
9
10	root	1.1	#include <sys/types.h>
11			#include <sys/stat.h>
12	root	1.10
13	root	1.1	#include <unistd.h>
14			#include <fcntl.h>
15			#include <signal.h>
16			#include <sched.h>
17
18			#include <pthread.h>
19
20			typedef void InputStream; / hack, but 5.6.1 is simply toooo old ;) */
21			typedef void OutputStream; / hack, but 5.6.1 is simply toooo old ;) */
22			typedef void InOutStream; / hack, but 5.6.1 is simply toooo old ;) */
23
24	root	1.4	#if __ia64
25			# define STACKSIZE 65536
26	root	1.1	#else
27	root	1.4	# define STACKSIZE 4096
28	root	1.1	#endif
29
30			enum {
31			REQ_QUIT,
32			REQ_OPEN, REQ_CLOSE,
33			REQ_READ, REQ_WRITE, REQ_READAHEAD,
34			REQ_STAT, REQ_LSTAT, REQ_FSTAT, REQ_UNLINK,
35			REQ_FSYNC, REQ_FDATASYNC,
36			};
37
38			typedef struct aio_cb {
39	root	1.3	struct aio_cb *volatile next;
40	root	1.1
41			int type;
42
43			int fd;
44			off_t offset;
45			size_t length;
46			ssize_t result;
47			mode_t mode; /* open */
48			int errorno;
49	root	1.13	SV data, callback, *fh;
50	root	1.1	void *dataptr;
51			STRLEN dataoffset;
52
53			Stat_t *statdata;
54			} aio_cb;
55
56			typedef aio_cb *aio_req;
57
58			static int started;
59	root	1.11	static volatile int nreqs;
60	root	1.4	static int max_outstanding = 1<<30;
61	root	1.3	static int respipe [2];
62	root	1.1
63	root	1.3	static pthread_mutex_t reslock = PTHREAD_MUTEX_INITIALIZER;
64			static pthread_mutex_t reqlock = PTHREAD_MUTEX_INITIALIZER;
65			static pthread_cond_t reqwait = PTHREAD_COND_INITIALIZER;
66
67			static volatile aio_req reqs, reqe; /* queue start, queue end */
68			static volatile aio_req ress, rese; /* queue start, queue end */
69	root	1.1
70			static void
71			poll_wait ()
72			{
73	root	1.11	if (nreqs && !ress)
74			{
75			fd_set rfd;
76			FD_ZERO(&rfd);
77			FD_SET(respipe [0], &rfd);
78	root	1.3
79	root	1.11	select (respipe [0] + 1, &rfd, 0, 0, 0);
80			}
81	root	1.1	}
82
83			static int
84	root	1.5	poll_cb ()
85	root	1.1	{
86			dSP;
87			int count = 0;
88	root	1.11	aio_req req, prv;
89
90			pthread_mutex_lock (&reslock);
91
92	root	1.3	{
93	root	1.11	/* read any signals sent by the worker threads */
94	root	1.3	char buf [32];
95			while (read (respipe [0], buf, 32) > 0)
96			;
97			}
98	root	1.1
99	root	1.11	req = ress;
100			ress = rese = 0;
101	root	1.3
102	root	1.11	pthread_mutex_unlock (&reslock);
103	root	1.3
104	root	1.11	while (req)
105			{
106	root	1.1	nreqs--;
107
108			if (req->type == REQ_QUIT)
109			started--;
110			else
111			{
112			int errorno = errno;
113			errno = req->errorno;
114
115			if (req->type == REQ_READ)
116			SvCUR_set (req->data, req->dataoffset
117			+ req->result > 0 ? req->result : 0);
118
119			if (req->data)
120			SvREFCNT_dec (req->data);
121
122	root	1.13	if (req->fh)
123			SvREFCNT_dec (req->fh);
124
125	root	1.1	if (req->type == REQ_STAT \|\| req->type == REQ_LSTAT \|\| req->type == REQ_FSTAT)
126			{
127			PL_laststype = req->type == REQ_LSTAT ? OP_LSTAT : OP_STAT;
128			PL_laststatval = req->result;
129			PL_statcache = *(req->statdata);
130
131			Safefree (req->statdata);
132			}
133
134	root	1.13	ENTER;
135	root	1.1	PUSHMARK (SP);
136			XPUSHs (sv_2mortal (newSViv (req->result)));
137	root	1.2
138			if (req->type == REQ_OPEN)
139			{
140			/* convert fd to fh */
141			SV *fh;
142
143			PUTBACK;
144			call_pv ("IO::AIO::_fd2fh", G_SCALAR \| G_EVAL);
145			SPAGAIN;
146
147	root	1.13	fh = SvREFCNT_inc (POPs);
148	root	1.2
149			PUSHMARK (SP);
150	root	1.13	XPUSHs (sv_2mortal (fh));
151	root	1.2	}
152
153	root	1.8	if (SvOK (req->callback))
154			{
155			PUTBACK;
156			call_sv (req->callback, G_VOID \| G_EVAL);
157			SPAGAIN;
158			}
159	root	1.13
160			LEAVE;
161	root	1.1
162			if (req->callback)
163			SvREFCNT_dec (req->callback);
164
165			errno = errorno;
166			count++;
167			}
168
169	root	1.11	prv = req;
170			req = req->next;
171			Safefree (prv);
172
173			/* TODO: croak on errors? */
174	root	1.1	}
175
176			return count;
177			}
178
179	root	1.4	static void aio_proc(void arg);
180
181			static void
182			start_thread (void)
183			{
184			sigset_t fullsigset, oldsigset;
185			pthread_t tid;
186			pthread_attr_t attr;
187
188			pthread_attr_init (&attr);
189			pthread_attr_setstacksize (&attr, STACKSIZE);
190			pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
191
192			sigfillset (&fullsigset);
193			sigprocmask (SIG_SETMASK, &fullsigset, &oldsigset);
194
195			if (pthread_create (&tid, &attr, aio_proc, 0) == 0)
196			started++;
197
198			sigprocmask (SIG_SETMASK, &oldsigset, 0);
199			}
200
201			static void
202			send_req (aio_req req)
203			{
204			nreqs++;
205
206			pthread_mutex_lock (&reqlock);
207
208			req->next = 0;
209
210			if (reqe)
211			{
212			reqe->next = req;
213			reqe = req;
214			}
215			else
216			reqe = reqs = req;
217
218			pthread_cond_signal (&reqwait);
219			pthread_mutex_unlock (&reqlock);
220
221			while (nreqs > max_outstanding)
222			{
223			poll_wait ();
224			poll_cb ();
225			}
226			}
227
228			static void
229			end_thread (void)
230			{
231			aio_req req;
232			New (0, req, 1, aio_cb);
233			req->type = REQ_QUIT;
234
235			send_req (req);
236			}
237
238	root	1.17	/* work around various missing functions */
239
240			#if !HAVE_PREADWRITE
241			# define pread aio_pread
242			# define pwrite aio_pwrite
243
244			/*
245			* make our pread/pwrite safe against themselves, but not against
246			* normal read/write by using a mutex. slows down execution a lot,
247			* but that's your problem, not mine.
248			*/
249			static pthread_mutex_t iolock = PTHREAD_MUTEX_INITIALIZER;
250
251			static ssize_t
252			pread (int fd, void *buf, size_t count, off_t offset)
253			{
254			ssize_t res;
255			off_t ooffset;
256
257			pthread_mutex_lock (&iolock);
258			ooffset = lseek (fd, 0, SEEK_CUR);
259			lseek (fd, offset, SEEK_SET);
260			res = read (fd, buf, count);
261			lseek (fd, ooffset, SEEK_SET);
262			pthread_mutex_unlock (&iolock);
263
264			return res;
265			}
266
267			static ssize_t
268			pwrite (int fd, void *buf, size_t count, off_t offset)
269			{
270			ssize_t res;
271			off_t ooffset;
272
273			pthread_mutex_lock (&iolock);
274			ooffset = lseek (fd, 0, SEEK_CUR);
275			lseek (fd, offset, SEEK_SET);
276			res = write (fd, buf, count);
277			lseek (fd, offset, SEEK_SET);
278			pthread_mutex_unlock (&iolock);
279
280			return res;
281			}
282			#endif
283
284			#if !HAVE_FDATASYNC
285			# define fdatasync fsync
286			#endif
287
288			#if !HAVE_READAHEAD
289			# define readahead aio_readahead
290
291			static char readahead_buf[4096];
292
293			static ssize_t
294			readahead (int fd, off_t offset, size_t count)
295			{
296			while (count > 0)
297			{
298			size_t len = count < sizeof (readahead_buf) ? count : sizeof (readahead_buf);
299
300			pread (fd, readahead_buf, len, offset);
301			offset += len;
302			count -= len;
303			}
304
305			errno = 0;
306			}
307			#endif
308
309	root	1.1	static void *
310			aio_proc (void *thr_arg)
311			{
312			aio_req req;
313	root	1.3	int type;
314	root	1.1
315	root	1.3	do
316	root	1.1	{
317	root	1.3	pthread_mutex_lock (&reqlock);
318
319			for (;;)
320			{
321			req = reqs;
322
323			if (reqs)
324			{
325			reqs = reqs->next;
326			if (!reqs) reqe = 0;
327			}
328
329			if (req)
330			break;
331
332			pthread_cond_wait (&reqwait, &reqlock);
333			}
334
335			pthread_mutex_unlock (&reqlock);
336
337	root	1.1	errno = 0; /* strictly unnecessary */
338
339	root	1.3	type = req->type;
340
341			switch (type)
342	root	1.1	{
343	root	1.10	case REQ_READ: req->result = pread (req->fd, req->dataptr, req->length, req->offset); break;
344			case REQ_WRITE: req->result = pwrite (req->fd, req->dataptr, req->length, req->offset); break;
345	root	1.16
346	root	1.1	case REQ_READAHEAD: req->result = readahead (req->fd, req->offset, req->length); break;
347
348			case REQ_STAT: req->result = stat (req->dataptr, req->statdata); break;
349			case REQ_LSTAT: req->result = lstat (req->dataptr, req->statdata); break;
350			case REQ_FSTAT: req->result = fstat (req->fd , req->statdata); break;
351
352			case REQ_OPEN: req->result = open (req->dataptr, req->fd, req->mode); break;
353			case REQ_CLOSE: req->result = close (req->fd); break;
354			case REQ_UNLINK: req->result = unlink (req->dataptr); break;
355
356	root	1.17	case REQ_FDATASYNC: req->result = fdatasync (req->fd); break;
357	root	1.1	case REQ_FSYNC: req->result = fsync (req->fd); break;
358
359			case REQ_QUIT:
360	root	1.3	break;
361	root	1.1
362			default:
363			req->result = ENOSYS;
364			break;
365			}
366
367			req->errorno = errno;
368	root	1.3
369			pthread_mutex_lock (&reslock);
370
371			req->next = 0;
372
373			if (rese)
374			{
375			rese->next = req;
376			rese = req;
377			}
378			else
379			{
380			rese = ress = req;
381
382			/* write a dummy byte to the pipe so fh becomes ready */
383			write (respipe [1], &respipe, 1);
384			}
385
386			pthread_mutex_unlock (&reslock);
387	root	1.1	}
388	root	1.3	while (type != REQ_QUIT);
389	root	1.1
390			return 0;
391			}
392
393			MODULE = IO::AIO PACKAGE = IO::AIO
394
395	root	1.8	PROTOTYPES: ENABLE
396
397	root	1.1	BOOT:
398			{
399	root	1.3	if (pipe (respipe))
400			croak ("unable to initialize result pipe");
401	root	1.1
402	root	1.3	if (fcntl (respipe [0], F_SETFL, O_NONBLOCK))
403	root	1.1	croak ("cannot set result pipe to nonblocking mode");
404
405	root	1.3	if (fcntl (respipe [1], F_SETFL, O_NONBLOCK))
406	root	1.1	croak ("cannot set result pipe to nonblocking mode");
407			}
408
409			void
410			min_parallel(nthreads)
411			int nthreads
412			PROTOTYPE: $
413			CODE:
414			while (nthreads > started)
415			start_thread ();
416
417			void
418			max_parallel(nthreads)
419			int nthreads
420			PROTOTYPE: $
421			CODE:
422			{
423			int cur = started;
424			while (cur > nthreads)
425			{
426			end_thread ();
427			cur--;
428			}
429
430			while (started > nthreads)
431			{
432			poll_wait ();
433	root	1.5	poll_cb ();
434	root	1.1	}
435			}
436
437	root	1.4	int
438			max_outstanding(nreqs)
439			int nreqs
440			PROTOTYPE: $
441			CODE:
442			RETVAL = max_outstanding;
443			max_outstanding = nreqs;
444
445	root	1.1	void
446	root	1.8	aio_open(pathname,flags,mode,callback=&PL_sv_undef)
447	root	1.1	SV * pathname
448			int flags
449			int mode
450			SV * callback
451	root	1.8	PROTOTYPE: $$$;$
452	root	1.1	CODE:
453			{
454			aio_req req;
455
456			Newz (0, req, 1, aio_cb);
457
458			if (!req)
459			croak ("out of memory during aio_req allocation");
460
461			req->type = REQ_OPEN;
462			req->data = newSVsv (pathname);
463			req->dataptr = SvPV_nolen (req->data);
464			req->fd = flags;
465			req->mode = mode;
466			req->callback = SvREFCNT_inc (callback);
467
468			send_req (req);
469			}
470
471			void
472	root	1.8	aio_close(fh,callback=&PL_sv_undef)
473	root	1.13	SV * fh
474			SV * callback
475	root	1.8	PROTOTYPE: $;$
476	root	1.1	ALIAS:
477			aio_close = REQ_CLOSE
478			aio_fsync = REQ_FSYNC
479			aio_fdatasync = REQ_FDATASYNC
480			CODE:
481			{
482			aio_req req;
483
484			Newz (0, req, 1, aio_cb);
485
486			if (!req)
487			croak ("out of memory during aio_req allocation");
488
489			req->type = ix;
490	root	1.13	req->fh = newSVsv (fh);
491			req->fd = PerlIO_fileno (IoIFP (sv_2io (fh)));
492	root	1.1	req->callback = SvREFCNT_inc (callback);
493
494			send_req (req);
495			}
496
497			void
498	root	1.8	aio_read(fh,offset,length,data,dataoffset,callback=&PL_sv_undef)
499	root	1.13	SV * fh
500			UV offset
501			IV length
502			SV * data
503			IV dataoffset
504			SV * callback
505			ALIAS:
506			aio_read = REQ_READ
507			aio_write = REQ_WRITE
508	root	1.8	PROTOTYPE: $$$$$;$
509	root	1.1	CODE:
510	root	1.13	{
511			aio_req req;
512			STRLEN svlen;
513			char *svptr = SvPV (data, svlen);
514
515			SvUPGRADE (data, SVt_PV);
516			SvPOK_on (data);
517	root	1.1
518	root	1.13	if (dataoffset < 0)
519			dataoffset += svlen;
520
521			if (dataoffset < 0 \|\| dataoffset > svlen)
522			croak ("data offset outside of string");
523
524			if (ix == REQ_WRITE)
525			{
526			/* write: check length and adjust. */
527			if (length < 0 \|\| length + dataoffset > svlen)
528			length = svlen - dataoffset;
529			}
530			else
531			{
532			/* read: grow scalar as necessary */
533			svptr = SvGROW (data, length + dataoffset);
534			}
535
536			if (length < 0)
537			croak ("length must not be negative");
538
539			Newz (0, req, 1, aio_cb);
540
541			if (!req)
542			croak ("out of memory during aio_req allocation");
543
544			req->type = ix;
545			req->fh = newSVsv (fh);
546			req->fd = PerlIO_fileno (ix == REQ_READ ? IoIFP (sv_2io (fh))
547			: IoOFP (sv_2io (fh)));
548			req->offset = offset;
549			req->length = length;
550			req->data = SvREFCNT_inc (data);
551			req->dataptr = (char *)svptr + dataoffset;
552			req->callback = SvREFCNT_inc (callback);
553
554			send_req (req);
555			}
556	root	1.1
557			void
558	root	1.8	aio_readahead(fh,offset,length,callback=&PL_sv_undef)
559	root	1.13	SV * fh
560			UV offset
561			IV length
562			SV * callback
563	root	1.8	PROTOTYPE: $$$;$
564	root	1.1	CODE:
565			{
566			aio_req req;
567
568			if (length < 0)
569			croak ("length must not be negative");
570
571			Newz (0, req, 1, aio_cb);
572
573			if (!req)
574			croak ("out of memory during aio_req allocation");
575
576			req->type = REQ_READAHEAD;
577	root	1.13	req->fh = newSVsv (fh);
578			req->fd = PerlIO_fileno (IoIFP (sv_2io (fh)));
579	root	1.1	req->offset = offset;
580			req->length = length;
581			req->callback = SvREFCNT_inc (callback);
582
583			send_req (req);
584			}
585
586			void
587	root	1.8	aio_stat(fh_or_path,callback=&PL_sv_undef)
588	root	1.1	SV * fh_or_path
589			SV * callback
590			ALIAS:
591	root	1.8	aio_stat = REQ_STAT
592			aio_lstat = REQ_LSTAT
593	root	1.1	CODE:
594			{
595			aio_req req;
596
597			Newz (0, req, 1, aio_cb);
598
599			if (!req)
600			croak ("out of memory during aio_req allocation");
601
602			New (0, req->statdata, 1, Stat_t);
603
604			if (!req->statdata)
605			croak ("out of memory during aio_req->statdata allocation");
606
607			if (SvPOK (fh_or_path))
608			{
609	root	1.8	req->type = ix;
610	root	1.1	req->data = newSVsv (fh_or_path);
611			req->dataptr = SvPV_nolen (req->data);
612			}
613			else
614			{
615			req->type = REQ_FSTAT;
616	root	1.13	req->fh = newSVsv (fh_or_path);
617	root	1.1	req->fd = PerlIO_fileno (IoIFP (sv_2io (fh_or_path)));
618			}
619
620			req->callback = SvREFCNT_inc (callback);
621
622			send_req (req);
623			}
624
625			void
626	root	1.8	aio_unlink(pathname,callback=&PL_sv_undef)
627	root	1.1	SV * pathname
628			SV * callback
629			CODE:
630			{
631			aio_req req;
632
633			Newz (0, req, 1, aio_cb);
634
635			if (!req)
636			croak ("out of memory during aio_req allocation");
637
638			req->type = REQ_UNLINK;
639			req->data = newSVsv (pathname);
640			req->dataptr = SvPV_nolen (req->data);
641			req->callback = SvREFCNT_inc (callback);
642
643			send_req (req);
644			}
645
646	root	1.6	void
647			flush()
648			PROTOTYPE:
649			CODE:
650			while (nreqs)
651			{
652			poll_wait ();
653			poll_cb ();
654			}
655
656	root	1.7	void
657			poll()
658			PROTOTYPE:
659			CODE:
660			if (nreqs)
661			{
662			poll_wait ();
663			poll_cb ();
664			}
665
666	root	1.1	int
667			poll_fileno()
668			PROTOTYPE:
669			CODE:
670	root	1.3	RETVAL = respipe [0];
671	root	1.1	OUTPUT:
672			RETVAL
673
674			int
675			poll_cb(...)
676			PROTOTYPE:
677			CODE:
678	root	1.5	RETVAL = poll_cb ();
679	root	1.1	OUTPUT:
680			RETVAL
681
682			void
683			poll_wait()
684			PROTOTYPE:
685			CODE:
686	root	1.3	if (nreqs)
687			poll_wait ();
688	root	1.1
689			int
690			nreqs()
691			PROTOTYPE:
692			CODE:
693			RETVAL = nreqs;
694			OUTPUT:
695			RETVAL
696