IO-AIO/AIO.xs

#define _REENTRANT 1
#include <errno.h>

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

#include "autoconf/config.h"

#include <pthread.h>

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

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

#if HAVE_SENDFILE
# if __linux
#  include <sys/sendfile.h>
# elif __freebsd
#  include <sys/socket.h>
#  include <sys/uio.h>
# elif __hpux
#  include <sys/socket.h>
# else
#  error sendfile support requested but not available
# endif
#endif

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

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

typedef struct aio_cb {
  struct aio_cb *volatile next;

  int type;

  int fd, fd2;
  off_t offset;
  size_t length;
  ssize_t result;
  mode_t mode; /* open */
  int errorno;
  SV *data, *callback;
  SV *fh, *fh2;
  void *dataptr, *data2ptr;
  STRLEN dataoffset;

  Stat_t *statdata;
} aio_cb;

typedef aio_cb *aio_req;

static int started, wanted;
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 free_req (aio_req req)
{
  if (req->data)
    SvREFCNT_dec (req->data);

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

  if (req->fh2)
    SvREFCNT_dec (req->fh2);

  if (req->statdata)
    Safefree (req->statdata);

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

  Safefree (req);
}

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;
  int do_croak = 0;
  aio_req req;

  for (;;)
    {
      pthread_mutex_lock (&reslock);
      req = ress;

      if (req)
        {
          ress = req->next;

          if (!ress)
            {
              /* read any signals sent by the worker threads */
              char buf [32];
              while (read (respipe [0], buf, 32) == 32)
                ;

              rese = 0;
            }
        }

      pthread_mutex_unlock (&reslock);

      if (!req)
        break;

      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->data2ptr && (req->type == REQ_READ || req->type == REQ_WRITE))
            SvREADONLY_off (req->data);

          if (req->statdata)
            {
              PL_laststype   = req->type == REQ_LSTAT ? OP_LSTAT : OP_STAT;
              PL_laststatval = req->result;
              PL_statcache   = *(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;

              if (SvTRUE (ERRSV))
                {
                  free_req (req);
                  croak (0);
                }
            }

          LEAVE;

          errno = errorno;
          count++;
        }

      free_req (req);
    }

  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)
{
  while (started < wanted && nreqs >= started)
    start_thread ();

  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);

  if (nreqs > max_outstanding)
    for (;;)
      {
        poll_cb ();

        if (nreqs <= max_outstanding)
          break;

        poll_wait ();
      }
}

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

  send_req (req);
}

static void min_parallel (int nthreads)
{
  if (wanted < nthreads)
    wanted = nthreads;
}

static void max_parallel (int nthreads)
{
  int cur = started;

  if (wanted > nthreads)
    wanted = nthreads;

  while (cur > wanted)
    {
      end_thread ();
      cur--;
    }

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

static void create_pipe ()
{
  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");
}

static void atfork_prepare (void)
{
  pthread_mutex_lock (&reqlock);
  pthread_mutex_lock (&reslock);
}

static void atfork_parent (void)
{
  pthread_mutex_unlock (&reslock);
  pthread_mutex_unlock (&reqlock);
}

static void atfork_child (void)
{
  aio_req prv;

  started = 0;

  while (reqs)
    {
      prv = reqs;
      reqs = prv->next;
      free_req (prv);
    }

  reqs = reqe = 0;
      
  while (ress)
    {
      prv = ress;
      ress = prv->next;
      free_req (prv);
    }
      
  ress = rese = 0;

  close (respipe [0]);
  close (respipe [1]);
  create_pipe ();

  atfork_parent ();
}

/*****************************************************************************/
/* 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

/* sendfile always needs emulation */
static ssize_t
sendfile_ (int ofd, int ifd, off_t offset, size_t count)
{
   ssize_t res;

   if (!count)
     return 0;

#if __linux
   res = sendfile (ofd, ifd, &offset, count);

#elif __freebsd
   /*
    * Of course, the freebsd sendfile is a dire hack with no thoughts
    * wasted on making it similar to other i/o functions.
    */
   {
     off_t sbytes;
     res = sendfile (ifd, ofd, offset, count, 0, &sbytes, 0);

     if (!res && errno == EAGAIN)
       /* maybe on others, too, as usual, the manpage leaves you guessing */
       res = sbytes;
   }

#elif __hpux
   res = sendfile (ofd, ifd, offset, count, 0, 0);

#else
   res = -1;
   errno = ENOSYS;
#endif

   if (res < 0 && (errno == ENOSYS || errno == EINVAL || errno == ENOTSOCK))
     {
       /* emulate sendfile. this is a major pain in the ass */
       char *buf = malloc (4096);
       res = 0;

       for (;;)
         {
           ssize_t cnt;
           
           cnt = pread (ifd, buf, 4096, offset);

           if (cnt <= 0)
             {
               if (cnt && !res) res = -1;
               break;
             }

           cnt = write (ofd, buf, cnt);

           if (cnt <= 0)
             {
               if (cnt && !res) res = -1;
               break;
             }

           offset += cnt;
           res    += cnt;
         }

       {
         int errorno = errno;
         free (buf);
         errno = errorno;
       }
     }

   return res;
}

/*****************************************************************************/

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_SENDFILE:  req->result = sendfile_ (req->fd, req->fd2, 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_RMDIR:     req->result = rmdir     (req->dataptr); break;
          case REQ_SYMLINK:   req->result = symlink   (req->data2ptr, 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;
}

#define dREQ                                                    \
  aio_req req;                                                  \
                                                                \
  if (SvOK (callback) && !SvROK (callback))                     \
    croak ("clalback must be undef or of reference type");      \
                                                                \
  Newz (0, req, 1, aio_cb);                                     \
  if (!req)                                                     \
    croak ("out of memory during aio_req allocation");          \
                                                                \
  req->callback = newSVsv (callback);
        
MODULE = IO::AIO                PACKAGE = IO::AIO

PROTOTYPES: ENABLE

BOOT:
{
        create_pipe ();
        pthread_atfork (atfork_prepare, atfork_parent, atfork_child);
}

void
min_parallel(nthreads)
        int     nthreads
        PROTOTYPE: $

void
max_parallel(nthreads)
        int     nthreads
        PROTOTYPE: $

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:
{
        dREQ;

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

        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:
{
        dREQ;

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

        send_req (req);
}

void
aio_read(fh,offset,length,data,dataoffset,callback=&PL_sv_undef)
        SV *    fh
        UV      offset
        UV      length
        SV *    data
        UV      dataoffset
        SV *    callback
        ALIAS:
           aio_read  = REQ_READ
           aio_write = REQ_WRITE
        PROTOTYPE: $$$$$;$
        CODE:
{
        aio_req req;
        STRLEN svlen;
        char *svptr = SvPVbyte (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");

        {
          dREQ;

          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;

          if (!SvREADONLY (data))
            {
              SvREADONLY_on (data);
              req->data2ptr = (void *)data;
            }

          send_req (req);
        }
}

void
aio_sendfile(out_fh,in_fh,in_offset,length,callback=&PL_sv_undef)
        SV *    out_fh
        SV *    in_fh
        UV      in_offset
        UV      length
        SV *    callback
        PROTOTYPE: $$$$;$
        CODE:
{
        dREQ;

        req->type = REQ_SENDFILE;
        req->fh = newSVsv (out_fh);
        req->fd = PerlIO_fileno (IoIFP (sv_2io (out_fh)));
        req->fh2 = newSVsv (in_fh);
        req->fd2 = PerlIO_fileno (IoIFP (sv_2io (in_fh)));
        req->offset = in_offset;
        req->length = length;

        send_req (req);
}

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

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

        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:
{
        dREQ;

        New (0, req->statdata, 1, Stat_t);
        if (!req->statdata)
          {
            free_req (req);
            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 = SvPVbyte_nolen (req->data);
          }
        else
          {
            req->type = REQ_FSTAT;
            req->fh = newSVsv (fh_or_path);
            req->fd = PerlIO_fileno (IoIFP (sv_2io (fh_or_path)));
          }

        send_req (req);
}

void
aio_unlink(pathname,callback=&PL_sv_undef)
        SV * pathname
        SV * callback
        ALIAS:
           aio_unlink = REQ_UNLINK
           aio_rmdir  = REQ_RMDIR
        CODE:
{
        dREQ;
        
        req->type = ix;
        req->data = newSVsv (pathname);
        req->dataptr = SvPVbyte_nolen (req->data);
        
        send_req (req);
}

void
aio_symlink(oldpath,newpath,callback=&PL_sv_undef)
        SV * oldpath
        SV * newpath
        SV * callback
        CODE:
{
        dREQ;
        
        req->type = REQ_SYMLINK;
        req->fh = newSVsv (oldpath);
        req->data2ptr = SvPVbyte_nolen (req->fh);
        req->data = newSVsv (newpath);
        req->dataptr = SvPVbyte_nolen (req->data);
        
        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:	1.34
Committed:	Tue Aug 23 00:03:14 2005 UTC (18 years, 8 months ago) by root
Branch:	MAIN
Changes since 1.33:	+2 -0 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	1.32	#include <pthread.h>
11
12	root	1.1	#include <sys/types.h>
13			#include <sys/stat.h>
14	root	1.10
15	root	1.1	#include <unistd.h>
16			#include <fcntl.h>
17			#include <signal.h>
18			#include <sched.h>
19
20	root	1.32	#if HAVE_SENDFILE
21			# if __linux
22			# include <sys/sendfile.h>
23			# elif __freebsd
24			# include <sys/socket.h>
25			# include <sys/uio.h>
26			# elif __hpux
27			# include <sys/socket.h>
28	root	1.34	# else
29			# error sendfile support requested but not available
30	root	1.32	# endif
31			#endif
32	root	1.1
33	root	1.4	#if __ia64
34			# define STACKSIZE 65536
35	root	1.1	#else
36	root	1.4	# define STACKSIZE 4096
37	root	1.1	#endif
38
39			enum {
40			REQ_QUIT,
41			REQ_OPEN, REQ_CLOSE,
42			REQ_READ, REQ_WRITE, REQ_READAHEAD,
43	root	1.32	REQ_SENDFILE,
44	root	1.22	REQ_STAT, REQ_LSTAT, REQ_FSTAT,
45	root	1.1	REQ_FSYNC, REQ_FDATASYNC,
46	root	1.23	REQ_UNLINK, REQ_RMDIR,
47	root	1.22	REQ_SYMLINK,
48	root	1.1	};
49
50			typedef struct aio_cb {
51	root	1.3	struct aio_cb *volatile next;
52	root	1.1
53			int type;
54
55	root	1.32	int fd, fd2;
56	root	1.1	off_t offset;
57			size_t length;
58			ssize_t result;
59			mode_t mode; /* open */
60			int errorno;
61	root	1.32	SV data, callback;
62			SV fh, fh2;
63	root	1.22	void dataptr, data2ptr;
64	root	1.1	STRLEN dataoffset;
65
66			Stat_t *statdata;
67			} aio_cb;
68
69			typedef aio_cb *aio_req;
70
71	root	1.30	static int started, wanted;
72	root	1.11	static volatile int nreqs;
73	root	1.4	static int max_outstanding = 1<<30;
74	root	1.3	static int respipe [2];
75	root	1.1
76	root	1.3	static pthread_mutex_t reslock = PTHREAD_MUTEX_INITIALIZER;
77			static pthread_mutex_t reqlock = PTHREAD_MUTEX_INITIALIZER;
78			static pthread_cond_t reqwait = PTHREAD_COND_INITIALIZER;
79
80			static volatile aio_req reqs, reqe; /* queue start, queue end */
81			static volatile aio_req ress, rese; /* queue start, queue end */
82	root	1.1
83	root	1.26	static void free_req (aio_req req)
84			{
85			if (req->data)
86			SvREFCNT_dec (req->data);
87
88			if (req->fh)
89			SvREFCNT_dec (req->fh);
90
91	root	1.32	if (req->fh2)
92			SvREFCNT_dec (req->fh2);
93
94	root	1.27	if (req->statdata)
95	root	1.26	Safefree (req->statdata);
96
97			if (req->callback)
98			SvREFCNT_dec (req->callback);
99
100			Safefree (req);
101			}
102
103	root	1.1	static void
104			poll_wait ()
105			{
106	root	1.11	if (nreqs && !ress)
107			{
108			fd_set rfd;
109			FD_ZERO(&rfd);
110			FD_SET(respipe [0], &rfd);
111	root	1.3
112	root	1.11	select (respipe [0] + 1, &rfd, 0, 0, 0);
113			}
114	root	1.1	}
115
116			static int
117	root	1.5	poll_cb ()
118	root	1.1	{
119			dSP;
120			int count = 0;
121	root	1.24	int do_croak = 0;
122	root	1.27	aio_req req;
123
124			for (;;)
125			{
126			pthread_mutex_lock (&reslock);
127			req = ress;
128
129			if (req)
130			{
131			ress = req->next;
132	root	1.11
133	root	1.27	if (!ress)
134			{
135			/* read any signals sent by the worker threads */
136			char buf [32];
137			while (read (respipe [0], buf, 32) == 32)
138			;
139	root	1.30
140			rese = 0;
141	root	1.27	}
142			}
143	root	1.1
144	root	1.27	pthread_mutex_unlock (&reslock);
145	root	1.3
146	root	1.27	if (!req)
147			break;
148	root	1.3
149	root	1.1	nreqs--;
150
151			if (req->type == REQ_QUIT)
152			started--;
153			else
154			{
155			int errorno = errno;
156			errno = req->errorno;
157
158			if (req->type == REQ_READ)
159	root	1.27	SvCUR_set (req->data, req->dataoffset + (req->result > 0 ? req->result : 0));
160	root	1.1
161	root	1.28	if (req->data2ptr && (req->type == REQ_READ \|\| req->type == REQ_WRITE))
162			SvREADONLY_off (req->data);
163
164	root	1.27	if (req->statdata)
165	root	1.1	{
166			PL_laststype = req->type == REQ_LSTAT ? OP_LSTAT : OP_STAT;
167			PL_laststatval = req->result;
168			PL_statcache = *(req->statdata);
169			}
170
171	root	1.13	ENTER;
172	root	1.1	PUSHMARK (SP);
173			XPUSHs (sv_2mortal (newSViv (req->result)));
174	root	1.2
175			if (req->type == REQ_OPEN)
176			{
177			/* convert fd to fh */
178			SV *fh;
179
180			PUTBACK;
181			call_pv ("IO::AIO::_fd2fh", G_SCALAR \| G_EVAL);
182			SPAGAIN;
183
184	root	1.13	fh = SvREFCNT_inc (POPs);
185	root	1.2
186			PUSHMARK (SP);
187	root	1.13	XPUSHs (sv_2mortal (fh));
188	root	1.2	}
189
190	root	1.8	if (SvOK (req->callback))
191			{
192			PUTBACK;
193			call_sv (req->callback, G_VOID \| G_EVAL);
194			SPAGAIN;
195	root	1.27
196			if (SvTRUE (ERRSV))
197			{
198			free_req (req);
199			croak (0);
200			}
201	root	1.8	}
202	root	1.13
203	root	1.26	LEAVE;
204
205	root	1.1	errno = errorno;
206			count++;
207			}
208
209	root	1.27	free_req (req);
210	root	1.1	}
211
212			return count;
213			}
214
215	root	1.4	static void aio_proc(void arg);
216
217			static void
218			start_thread (void)
219			{
220			sigset_t fullsigset, oldsigset;
221			pthread_t tid;
222			pthread_attr_t attr;
223
224			pthread_attr_init (&attr);
225			pthread_attr_setstacksize (&attr, STACKSIZE);
226	root	1.31	pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
227	root	1.4
228			sigfillset (&fullsigset);
229			sigprocmask (SIG_SETMASK, &fullsigset, &oldsigset);
230
231			if (pthread_create (&tid, &attr, aio_proc, 0) == 0)
232			started++;
233
234			sigprocmask (SIG_SETMASK, &oldsigset, 0);
235			}
236
237			static void
238			send_req (aio_req req)
239			{
240	root	1.30	while (started < wanted && nreqs >= started)
241			start_thread ();
242
243	root	1.4	nreqs++;
244
245			pthread_mutex_lock (&reqlock);
246
247			req->next = 0;
248
249			if (reqe)
250			{
251			reqe->next = req;
252			reqe = req;
253			}
254			else
255			reqe = reqs = req;
256
257			pthread_cond_signal (&reqwait);
258			pthread_mutex_unlock (&reqlock);
259
260	root	1.27	if (nreqs > max_outstanding)
261			for (;;)
262			{
263			poll_cb ();
264
265			if (nreqs <= max_outstanding)
266			break;
267
268			poll_wait ();
269			}
270	root	1.4	}
271
272			static void
273			end_thread (void)
274			{
275			aio_req req;
276	root	1.26	Newz (0, req, 1, aio_cb);
277	root	1.4	req->type = REQ_QUIT;
278
279			send_req (req);
280			}
281
282	root	1.22	static void min_parallel (int nthreads)
283			{
284	root	1.30	if (wanted < nthreads)
285			wanted = nthreads;
286	root	1.22	}
287
288			static void max_parallel (int nthreads)
289			{
290			int cur = started;
291	root	1.27
292	root	1.30	if (wanted > nthreads)
293			wanted = nthreads;
294
295			while (cur > wanted)
296			{
297	root	1.22	end_thread ();
298			cur--;
299			}
300
301	root	1.30	while (started > wanted)
302	root	1.22	{
303			poll_wait ();
304			poll_cb ();
305			}
306			}
307
308	root	1.26	static void create_pipe ()
309	root	1.22	{
310	root	1.26	if (pipe (respipe))
311			croak ("unable to initialize result pipe");
312	root	1.22
313	root	1.26	if (fcntl (respipe [0], F_SETFL, O_NONBLOCK))
314			croak ("cannot set result pipe to nonblocking mode");
315	root	1.22
316	root	1.26	if (fcntl (respipe [1], F_SETFL, O_NONBLOCK))
317			croak ("cannot set result pipe to nonblocking mode");
318			}
319	root	1.22
320	root	1.26	static void atfork_prepare (void)
321			{
322	root	1.28	pthread_mutex_lock (&reqlock);
323	root	1.22	pthread_mutex_lock (&reslock);
324			}
325
326			static void atfork_parent (void)
327			{
328			pthread_mutex_unlock (&reslock);
329	root	1.26	pthread_mutex_unlock (&reqlock);
330			}
331
332			static void atfork_child (void)
333			{
334	root	1.28	aio_req prv;
335
336	root	1.26	started = 0;
337
338	root	1.28	while (reqs)
339			{
340			prv = reqs;
341			reqs = prv->next;
342			free_req (prv);
343			}
344
345			reqs = reqe = 0;
346
347			while (ress)
348			{
349			prv = ress;
350			ress = prv->next;
351			free_req (prv);
352			}
353
354			ress = rese = 0;
355
356	root	1.29	close (respipe [0]);
357			close (respipe [1]);
358			create_pipe ();
359
360	root	1.26	atfork_parent ();
361	root	1.22	}
362
363			/*****************************************************************************/
364	root	1.17	/* work around various missing functions */
365
366			#if !HAVE_PREADWRITE
367			# define pread aio_pread
368			# define pwrite aio_pwrite
369
370			/*
371			* make our pread/pwrite safe against themselves, but not against
372			* normal read/write by using a mutex. slows down execution a lot,
373			* but that's your problem, not mine.
374			*/
375			static pthread_mutex_t iolock = PTHREAD_MUTEX_INITIALIZER;
376
377			static ssize_t
378			pread (int fd, void *buf, size_t count, off_t offset)
379			{
380			ssize_t res;
381			off_t ooffset;
382
383			pthread_mutex_lock (&iolock);
384			ooffset = lseek (fd, 0, SEEK_CUR);
385			lseek (fd, offset, SEEK_SET);
386			res = read (fd, buf, count);
387			lseek (fd, ooffset, SEEK_SET);
388			pthread_mutex_unlock (&iolock);
389
390			return res;
391			}
392
393			static ssize_t
394			pwrite (int fd, void *buf, size_t count, off_t offset)
395			{
396			ssize_t res;
397			off_t ooffset;
398
399			pthread_mutex_lock (&iolock);
400			ooffset = lseek (fd, 0, SEEK_CUR);
401			lseek (fd, offset, SEEK_SET);
402			res = write (fd, buf, count);
403			lseek (fd, offset, SEEK_SET);
404			pthread_mutex_unlock (&iolock);
405
406			return res;
407			}
408			#endif
409
410			#if !HAVE_FDATASYNC
411			# define fdatasync fsync
412			#endif
413
414			#if !HAVE_READAHEAD
415			# define readahead aio_readahead
416
417			static char readahead_buf[4096];
418
419			static ssize_t
420			readahead (int fd, off_t offset, size_t count)
421			{
422			while (count > 0)
423			{
424			size_t len = count < sizeof (readahead_buf) ? count : sizeof (readahead_buf);
425
426			pread (fd, readahead_buf, len, offset);
427			offset += len;
428			count -= len;
429			}
430
431			errno = 0;
432			}
433			#endif
434
435	root	1.32	/* sendfile always needs emulation */
436			static ssize_t
437			sendfile_ (int ofd, int ifd, off_t offset, size_t count)
438			{
439			ssize_t res;
440
441			if (!count)
442			return 0;
443
444			#if __linux
445			res = sendfile (ofd, ifd, &offset, count);
446
447			#elif __freebsd
448			/*
449			* Of course, the freebsd sendfile is a dire hack with no thoughts
450			* wasted on making it similar to other i/o functions.
451			*/
452			{
453			off_t sbytes;
454			res = sendfile (ifd, ofd, offset, count, 0, &sbytes, 0);
455
456			if (!res && errno == EAGAIN)
457	root	1.33	/* maybe on others, too, as usual, the manpage leaves you guessing */
458	root	1.32	res = sbytes;
459			}
460
461			#elif __hpux
462			res = sendfile (ofd, ifd, offset, count, 0, 0);
463
464			#else
465			res = -1;
466			errno = ENOSYS;
467			#endif
468
469			if (res < 0 && (errno == ENOSYS \|\| errno == EINVAL \|\| errno == ENOTSOCK))
470			{
471			/* emulate sendfile. this is a major pain in the ass */
472			char *buf = malloc (4096);
473			res = 0;
474
475			for (;;)
476			{
477			ssize_t cnt;
478
479			cnt = pread (ifd, buf, 4096, offset);
480
481			if (cnt <= 0)
482			{
483			if (cnt && !res) res = -1;
484			break;
485			}
486
487			cnt = write (ofd, buf, cnt);
488
489			if (cnt <= 0)
490			{
491			if (cnt && !res) res = -1;
492			break;
493			}
494
495			offset += cnt;
496			res += cnt;
497			}
498
499			{
500			int errorno = errno;
501			free (buf);
502			errno = errorno;
503			}
504			}
505
506			return res;
507			}
508
509	root	1.22	/*****************************************************************************/
510
511	root	1.1	static void *
512			aio_proc (void *thr_arg)
513			{
514			aio_req req;
515	root	1.3	int type;
516	root	1.1
517	root	1.3	do
518	root	1.1	{
519	root	1.3	pthread_mutex_lock (&reqlock);
520
521			for (;;)
522			{
523			req = reqs;
524
525			if (reqs)
526			{
527			reqs = reqs->next;
528			if (!reqs) reqe = 0;
529			}
530
531			if (req)
532			break;
533
534			pthread_cond_wait (&reqwait, &reqlock);
535			}
536
537			pthread_mutex_unlock (&reqlock);
538
539	root	1.1	errno = 0; /* strictly unnecessary */
540
541	root	1.3	type = req->type;
542
543			switch (type)
544	root	1.1	{
545	root	1.10	case REQ_READ: req->result = pread (req->fd, req->dataptr, req->length, req->offset); break;
546			case REQ_WRITE: req->result = pwrite (req->fd, req->dataptr, req->length, req->offset); break;
547	root	1.16
548	root	1.1	case REQ_READAHEAD: req->result = readahead (req->fd, req->offset, req->length); break;
549	root	1.32	case REQ_SENDFILE: req->result = sendfile_ (req->fd, req->fd2, req->offset, req->length); break;
550	root	1.1
551			case REQ_STAT: req->result = stat (req->dataptr, req->statdata); break;
552			case REQ_LSTAT: req->result = lstat (req->dataptr, req->statdata); break;
553			case REQ_FSTAT: req->result = fstat (req->fd , req->statdata); break;
554
555			case REQ_OPEN: req->result = open (req->dataptr, req->fd, req->mode); break;
556			case REQ_CLOSE: req->result = close (req->fd); break;
557			case REQ_UNLINK: req->result = unlink (req->dataptr); break;
558	root	1.22	case REQ_RMDIR: req->result = rmdir (req->dataptr); break;
559			case REQ_SYMLINK: req->result = symlink (req->data2ptr, req->dataptr); break;
560	root	1.1
561	root	1.17	case REQ_FDATASYNC: req->result = fdatasync (req->fd); break;
562	root	1.1	case REQ_FSYNC: req->result = fsync (req->fd); break;
563
564			case REQ_QUIT:
565	root	1.3	break;
566	root	1.1
567			default:
568			req->result = ENOSYS;
569			break;
570			}
571
572			req->errorno = errno;
573	root	1.3
574			pthread_mutex_lock (&reslock);
575
576			req->next = 0;
577
578			if (rese)
579			{
580			rese->next = req;
581			rese = req;
582			}
583			else
584			{
585			rese = ress = req;
586
587			/* write a dummy byte to the pipe so fh becomes ready */
588			write (respipe [1], &respipe, 1);
589			}
590
591			pthread_mutex_unlock (&reslock);
592	root	1.1	}
593	root	1.3	while (type != REQ_QUIT);
594	root	1.1
595			return 0;
596			}
597
598	root	1.22	#define dREQ \
599			aio_req req; \
600			\
601			if (SvOK (callback) && !SvROK (callback)) \
602			croak ("clalback must be undef or of reference type"); \
603			\
604			Newz (0, req, 1, aio_cb); \
605			if (!req) \
606			croak ("out of memory during aio_req allocation"); \
607			\
608	root	1.27	req->callback = newSVsv (callback);
609	root	1.22
610	root	1.1	MODULE = IO::AIO PACKAGE = IO::AIO
611
612	root	1.8	PROTOTYPES: ENABLE
613
614	root	1.1	BOOT:
615			{
616	root	1.26	create_pipe ();
617	root	1.22	pthread_atfork (atfork_prepare, atfork_parent, atfork_child);
618	root	1.1	}
619
620			void
621			min_parallel(nthreads)
622			int nthreads
623			PROTOTYPE: $
624
625			void
626			max_parallel(nthreads)
627			int nthreads
628			PROTOTYPE: $
629
630	root	1.4	int
631			max_outstanding(nreqs)
632			int nreqs
633			PROTOTYPE: $
634			CODE:
635			RETVAL = max_outstanding;
636			max_outstanding = nreqs;
637
638	root	1.1	void
639	root	1.8	aio_open(pathname,flags,mode,callback=&PL_sv_undef)
640	root	1.1	SV * pathname
641			int flags
642			int mode
643			SV * callback
644	root	1.8	PROTOTYPE: $$$;$
645	root	1.1	CODE:
646			{
647	root	1.22	dREQ;
648	root	1.1
649			req->type = REQ_OPEN;
650			req->data = newSVsv (pathname);
651	root	1.22	req->dataptr = SvPVbyte_nolen (req->data);
652	root	1.1	req->fd = flags;
653			req->mode = mode;
654
655			send_req (req);
656			}
657
658			void
659	root	1.8	aio_close(fh,callback=&PL_sv_undef)
660	root	1.13	SV * fh
661			SV * callback
662	root	1.8	PROTOTYPE: $;$
663	root	1.1	ALIAS:
664			aio_close = REQ_CLOSE
665			aio_fsync = REQ_FSYNC
666			aio_fdatasync = REQ_FDATASYNC
667			CODE:
668			{
669	root	1.22	dREQ;
670	root	1.1
671			req->type = ix;
672	root	1.13	req->fh = newSVsv (fh);
673			req->fd = PerlIO_fileno (IoIFP (sv_2io (fh)));
674	root	1.1
675			send_req (req);
676			}
677
678			void
679	root	1.8	aio_read(fh,offset,length,data,dataoffset,callback=&PL_sv_undef)
680	root	1.13	SV * fh
681			UV offset
682	root	1.32	UV length
683	root	1.13	SV * data
684	root	1.32	UV dataoffset
685	root	1.13	SV * callback
686			ALIAS:
687			aio_read = REQ_READ
688			aio_write = REQ_WRITE
689	root	1.8	PROTOTYPE: $$$$$;$
690	root	1.1	CODE:
691	root	1.13	{
692			aio_req req;
693			STRLEN svlen;
694	root	1.21	char *svptr = SvPVbyte (data, svlen);
695	root	1.13
696			SvUPGRADE (data, SVt_PV);
697			SvPOK_on (data);
698	root	1.1
699	root	1.13	if (dataoffset < 0)
700			dataoffset += svlen;
701
702			if (dataoffset < 0 \|\| dataoffset > svlen)
703			croak ("data offset outside of string");
704
705			if (ix == REQ_WRITE)
706			{
707			/* write: check length and adjust. */
708			if (length < 0 \|\| length + dataoffset > svlen)
709			length = svlen - dataoffset;
710			}
711			else
712			{
713			/* read: grow scalar as necessary */
714			svptr = SvGROW (data, length + dataoffset);
715			}
716
717			if (length < 0)
718			croak ("length must not be negative");
719
720	root	1.22	{
721			dREQ;
722	root	1.13
723	root	1.22	req->type = ix;
724			req->fh = newSVsv (fh);
725			req->fd = PerlIO_fileno (ix == REQ_READ ? IoIFP (sv_2io (fh))
726			: IoOFP (sv_2io (fh)));
727			req->offset = offset;
728			req->length = length;
729			req->data = SvREFCNT_inc (data);
730			req->dataptr = (char *)svptr + dataoffset;
731	root	1.13
732	root	1.28	if (!SvREADONLY (data))
733			{
734			SvREADONLY_on (data);
735			req->data2ptr = (void *)data;
736			}
737
738	root	1.22	send_req (req);
739			}
740	root	1.13	}
741	root	1.1
742			void
743	root	1.32	aio_sendfile(out_fh,in_fh,in_offset,length,callback=&PL_sv_undef)
744			SV * out_fh
745			SV * in_fh
746			UV in_offset
747			UV length
748			SV * callback
749			PROTOTYPE: $$$$;$
750			CODE:
751			{
752			dREQ;
753
754			req->type = REQ_SENDFILE;
755			req->fh = newSVsv (out_fh);
756			req->fd = PerlIO_fileno (IoIFP (sv_2io (out_fh)));
757			req->fh2 = newSVsv (in_fh);
758			req->fd2 = PerlIO_fileno (IoIFP (sv_2io (in_fh)));
759			req->offset = in_offset;
760			req->length = length;
761
762			send_req (req);
763			}
764
765			void
766	root	1.8	aio_readahead(fh,offset,length,callback=&PL_sv_undef)
767	root	1.13	SV * fh
768			UV offset
769			IV length
770			SV * callback
771	root	1.8	PROTOTYPE: $$$;$
772	root	1.1	CODE:
773			{
774	root	1.22	dREQ;
775	root	1.1
776			req->type = REQ_READAHEAD;
777	root	1.13	req->fh = newSVsv (fh);
778			req->fd = PerlIO_fileno (IoIFP (sv_2io (fh)));
779	root	1.1	req->offset = offset;
780			req->length = length;
781
782			send_req (req);
783			}
784
785			void
786	root	1.8	aio_stat(fh_or_path,callback=&PL_sv_undef)
787	root	1.1	SV * fh_or_path
788			SV * callback
789			ALIAS:
790	root	1.8	aio_stat = REQ_STAT
791			aio_lstat = REQ_LSTAT
792	root	1.1	CODE:
793			{
794	root	1.22	dREQ;
795	root	1.1
796			New (0, req->statdata, 1, Stat_t);
797			if (!req->statdata)
798	root	1.27	{
799			free_req (req);
800			croak ("out of memory during aio_req->statdata allocation");
801			}
802	root	1.1
803			if (SvPOK (fh_or_path))
804			{
805	root	1.8	req->type = ix;
806	root	1.1	req->data = newSVsv (fh_or_path);
807	root	1.22	req->dataptr = SvPVbyte_nolen (req->data);
808	root	1.1	}
809			else
810			{
811			req->type = REQ_FSTAT;
812	root	1.13	req->fh = newSVsv (fh_or_path);
813	root	1.1	req->fd = PerlIO_fileno (IoIFP (sv_2io (fh_or_path)));
814			}
815
816			send_req (req);
817			}
818
819			void
820	root	1.8	aio_unlink(pathname,callback=&PL_sv_undef)
821	root	1.1	SV * pathname
822			SV * callback
823	root	1.22	ALIAS:
824			aio_unlink = REQ_UNLINK
825			aio_rmdir = REQ_RMDIR
826	root	1.1	CODE:
827			{
828	root	1.22	dREQ;
829	root	1.1
830	root	1.22	req->type = ix;
831			req->data = newSVsv (pathname);
832			req->dataptr = SvPVbyte_nolen (req->data);
833	root	1.1
834	root	1.22	send_req (req);
835			}
836
837			void
838			aio_symlink(oldpath,newpath,callback=&PL_sv_undef)
839			SV * oldpath
840			SV * newpath
841			SV * callback
842			CODE:
843			{
844			dREQ;
845	root	1.1
846	root	1.22	req->type = REQ_SYMLINK;
847			req->fh = newSVsv (oldpath);
848			req->data2ptr = SvPVbyte_nolen (req->fh);
849			req->data = newSVsv (newpath);
850			req->dataptr = SvPVbyte_nolen (req->data);
851	root	1.1
852			send_req (req);
853			}
854
855	root	1.6	void
856			flush()
857			PROTOTYPE:
858			CODE:
859			while (nreqs)
860			{
861			poll_wait ();
862			poll_cb ();
863			}
864
865	root	1.7	void
866			poll()
867			PROTOTYPE:
868			CODE:
869			if (nreqs)
870			{
871			poll_wait ();
872			poll_cb ();
873			}
874
875	root	1.1	int
876			poll_fileno()
877			PROTOTYPE:
878			CODE:
879	root	1.3	RETVAL = respipe [0];
880	root	1.1	OUTPUT:
881			RETVAL
882
883			int
884			poll_cb(...)
885			PROTOTYPE:
886			CODE:
887	root	1.5	RETVAL = poll_cb ();
888	root	1.1	OUTPUT:
889			RETVAL
890
891			void
892			poll_wait()
893			PROTOTYPE:
894			CODE:
895	root	1.3	if (nreqs)
896			poll_wait ();
897	root	1.1
898			int
899			nreqs()
900			PROTOTYPE:
901			CODE:
902			RETVAL = nreqs;
903			OUTPUT:
904			RETVAL
905