AnyEvent-FastPing/FastPing.xs

#define _POSIX_C_SOURCE 200112
#define _XOPEN_SOURCE 600
#define _LARGEFILE64_SOURCE 1

#ifdef __APPLE__
# define IPV6 0
#else
# define IPV6 1 // if you get compilation problems try to disable IPv6
#endif

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

#include <pthread.h>

#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <time.h>
#include <poll.h>
#include <unistd.h>
#include <inttypes.h>
#include <fcntl.h>
#include <errno.h>

#include <sys/types.h>
#include <sys/time.h>
#include <sys/socket.h>

#include <netinet/in.h>
#include <arpa/inet.h>

#ifdef __linux
# include <linux/icmp.h>
#endif
#if IPV6
# include <netinet/icmp6.h>
#endif

#define ICMP4_ECHO       8
#define ICMP4_ECHO_REPLY 0
#define ICMP6_ECHO       128
#define ICMP6_ECHO_REPLY 129

#define DRAIN_INTERVAL .000001 // how long to wait when sendto returns ENOBUFS, in seconds
#define MIN_INTERVAL   .000001 // minimum packet send interval, in seconds

#define HDR_SIZE_IP4  20
#define HDR_SIZE_IP6  48

//TODO: xread/xwrite for atomicity? we currently rely on the fact that the pip buffersize divides exactly by pointer sizes

typedef uint8_t addr_t[16];

typedef double tstamp;

tstamp
NOW ()
{
  struct timeval tv;
  gettimeofday (&tv, 0);
  return tv.tv_sec + tv.tv_usec * 0.000001;
}

typedef struct {
  int family;
  addr_t lo, hi;
  double interval;
  tstamp next;
} RANGE;

typedef struct {
  SV *id;
  double interval;
  int nranges;
  RANGE *ranges;
  uint32_t payload;
} REQ;

typedef struct {
  uint8_t version_ihl;
  uint8_t tos;
  uint16_t tot_len;

  uint16_t id;
  uint16_t flags;

  uint8_t ttl;
  uint8_t protocol;
  uint16_t cksum;

  uint32_t src;
  uint32_t dst;
} IP4HDR;

typedef struct {
  uint8_t version;
  uint8_t x1, x2, x3;

  uint16_t payload_len;
  uint8_t nxt_hdr;
  uint8_t hop_limit;

  uint8_t src[16];
  uint8_t dst[16];
} IP6HDR;

#define MAGIC 0xca4c

static uint16_t magic;

typedef struct {
  uint8_t type, code;
  uint16_t cksum;
  uint16_t id, seq;
  uint32_t payload;
  tstamp stamp; // be careful when accessing this
} PKT;

static pthread_t pthrid;
static int thr_send[2]; // send to worker
static int thr_recv[2]; // receive from worker

static int icmp4_fd, icmp6_fd;

static AV *cbs;

static uint16_t
icmp_cksum (void *data, unsigned int len)
{
  register int sum = 0;
  uint16_t *wp;

  assert (~len & 1);

  for (wp = (uint16_t *)data; len; wp++, len -= 2)
    sum += *wp;

  sum = (sum >> 16) + (sum & 0xffff);   /* add high 16 to low 16 */
  sum += sum >> 16;                     /* add carry */

  return ~sum;
}

static void
inc_addr (addr_t *addr)
{
  int len = sizeof (addr_t) - 1;

  do
    {
      if ((*addr)[len] != 0xff)
        {
          ++(*addr)[len];
          break;
        }

      (*addr)[len] = 0;
    }
  while (len--);
}

static void *
ping_proc (void *unused)
{
  PKT pkt;
  struct sockaddr_in sa4;
#if IPV6
  struct sockaddr_in6 sa6;
#endif

  memset (&pkt, 0, sizeof (pkt));

  memset (&sa4, 0, sizeof (sa4));
  sa4.sin_family  = AF_INET;
  sa4.sin_port    = 0;
#if IPV6
  memset (&sa6, 0, sizeof (sa6));
  sa6.sin6_family = AF_INET6;
  sa6.sin6_port   = 0;
#endif

  for (;;)
    {
      REQ *req;
      int len = read (thr_send [0], &req, sizeof (req));

      if (!len)
        pthread_exit (0);
      else if (len != sizeof (req))
        {
          perror ("AnyEvent::FastPing: short reead or read error");
          pthread_exit ((void *)-1);
        }

      //TODO: bind to source address

      pkt.code    = 0;
      pkt.id      = (uint16_t)magic;
      pkt.seq     = (uint16_t)~magic;
      pkt.payload = req->payload;

      tstamp now = NOW ();
      tstamp next = now;

      {
        int r;
        for (r = req->nranges; r--; )
          inc_addr (&req->ranges [r].hi);
      }

      while (req->nranges)
        {
          RANGE *range = req->ranges;

          if (!memcmp (&range->lo, &range->hi, sizeof (addr_t)))
            req->ranges [0] = req->ranges [--req->nranges];
          else
            {
              // ranges [0] is always the next range to ping
              tstamp wait = range->next - now;

              // compare with the global frequency limit
              {
                tstamp diff = next - now;

                if (wait < diff)
                  wait = diff;
                else if (range)
                  next = range->next;
              }

              if (wait > 0.)
                {
                  struct timespec ts;

                  ts.tv_sec  = wait;
                  ts.tv_nsec = (wait - ts.tv_sec) * 1000000000.;

                  nanosleep (&ts, 0);
                }

              now = NOW ();

              pkt.stamp = now;
              pkt.cksum = 0;

              if (range->family == AF_INET)
                {
                  pkt.type  = ICMP4_ECHO;
                  pkt.cksum = icmp_cksum (&pkt, sizeof (pkt));

                  memcpy (&sa4.sin_addr,
                          sizeof (addr_t) - sizeof (sa4.sin_addr) + (char *)&range->lo,
                          sizeof (sa4.sin_addr));

                  if (sendto (icmp4_fd, &pkt, sizeof (pkt), 0, (struct sockaddr *)&sa4, sizeof (sa4)) > 0)
                    errno = 0;
                }
              else
                {
#if IPV6
                  pkt.type = ICMP6_ECHO;

                  memcpy (&sa6.sin6_addr,
                          sizeof (addr_t) - sizeof (sa6.sin6_addr) + (char *)&range->lo,
                          sizeof (sa6.sin6_addr));

                  if (sendto (icmp6_fd, &pkt, sizeof (pkt), 0, (struct sockaddr *)&sa6, sizeof (sa6)) > 0)
                    errno = 0;
#endif
                }

              if (errno == ENOBUFS)
                {
                  struct timespec ts;

                  ts.tv_sec  = 0;
                  ts.tv_nsec = DRAIN_INTERVAL * 1000000000;

                  nanosleep (&ts, 0);
                }
              else
                {
                  inc_addr (&range->lo);

                  range->next = next;
                  range->next += range->interval;
                }

              next += req->interval;
            }

          // make a downheap operation
          int k = 0;
          int n = 0;
          for (;;)
            {
              ++n;
              int j = k * 2 + 1;

              if (j >= req->nranges)
                break;
              else if (j < req->nranges - 1)
                if (req->ranges [j].next > req->ranges [j + 1].next)
                  ++j;

              if (req->ranges [j].next >= req->ranges [k].next)
                break;

              RANGE temp = req->ranges [k];
              req->ranges [k] = req->ranges [j];
              req->ranges [j] = temp;

              k = j;
            }
        }

      write (thr_recv [1], &req, sizeof (req));
    }

  return 0;
}

static void
feed_reply (AV *res_av)
{
  if (av_len (res_av) < 0)
    return;

  dSP;
  SV *res = sv_2mortal (newRV_inc ((SV *)res_av));
  int i;

  ENTER;
  SAVETMPS;

  for (i = av_len (cbs) + 1; i--; )
    {
      SV *cb = *av_fetch (cbs, i, 1);

      PUSHMARK (SP);
      XPUSHs (res);
      PUTBACK;
      call_sv (cb, G_DISCARD | G_VOID);
    }

  FREETMPS;
  LEAVE;
}

static void
boot ()
{
  sigset_t fullsigset, oldsigset;
  pthread_attr_t attr;

  if (pipe (thr_send) < 0)
    croak ("AnyEvent::FastPing: unable to create send pipe");

  if (pipe (thr_recv) < 0)
    croak ("AnyEvent::FastPing: unable to create receive pipe");

  icmp4_fd = socket (AF_INET, SOCK_RAW, IPPROTO_ICMP);
  fcntl (icmp4_fd, F_SETFL, O_NONBLOCK);
#ifdef ICMP_FILTER
  {
    struct icmp_filter oval;
    oval.data = 0xffffffff & ~(1 << ICMP4_ECHO_REPLY);
    setsockopt (icmp4_fd, SOL_RAW, ICMP_FILTER, &oval, sizeof oval);
  }
#endif

#if IPV6
  icmp6_fd = socket (AF_INET6, SOCK_RAW, IPPROTO_ICMPV6);
  fcntl (icmp6_fd, F_SETFL, O_NONBLOCK);
# ifdef ICMP6_FILTER
  {
    struct icmp6_filter oval;
    ICMP6_FILTER_SETBLOCKALL (&oval);
    ICMP6_FILTER_SETPASS (ICMP6_ECHO_REPLY, &oval);
    setsockopt (icmp6_fd, IPPROTO_ICMPV6, ICMP6_FILTER, &oval, sizeof oval);
  }
# endif
#endif

  pthread_attr_init (&attr);
  pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
#ifdef PTHREAD_SCOPE_PROCESS
  pthread_attr_setscope (&attr, PTHREAD_SCOPE_PROCESS);
#endif

  sigfillset (&fullsigset);

  pthread_sigmask (SIG_SETMASK, &fullsigset, &oldsigset);

  if (pthread_create (&pthrid, &attr, ping_proc, 0))
    croak ("AnyEvent::FastPing: unable to create pinger thread");

  pthread_sigmask (SIG_SETMASK, &oldsigset, 0);

  sv_setiv (get_sv ("AnyEvent::FastPing::THR_REQ_FD", 1), thr_send [1]);
  sv_setiv (get_sv ("AnyEvent::FastPing::THR_RES_FD", 1), thr_recv [0]);

  sv_setiv (get_sv ("AnyEvent::FastPing::ICMP4_FD", 1), icmp4_fd);
  sv_setiv (get_sv ("AnyEvent::FastPing::ICMP6_FD", 1), icmp6_fd);
}

MODULE = AnyEvent::FastPing             PACKAGE = AnyEvent::FastPing

BOOT:
{
  HV *stash = gv_stashpv ("AnyEvent::FastPing", 1);

  cbs = get_av ("AnyEvent::FastPing::CB", 1);
  magic = getpid () ^ MAGIC;

  boot ();

  newCONSTSUB (stash, "ipv4_supported", newSViv (icmp4_fd >= 0));
  newCONSTSUB (stash, "ipv6_supported", newSViv (icmp6_fd >= 0));

  newCONSTSUB (stash, "icmp4_pktsize", newSViv (HDR_SIZE_IP4 + sizeof (PKT)));
  newCONSTSUB (stash, "icmp6_pktsize", newSViv (HDR_SIZE_IP6 + sizeof (PKT)));
}

PROTOTYPES: DISABLE

SV *
_req_icmp_ping (SV *ranges, NV interval, U32 payload, SV *id)
        CODE:
{
        if (!SvROK (ranges) || SvTYPE (SvRV (ranges)) != SVt_PVAV)
          croak ("address ranges must be given as arrayref with lo, hi pairs");

        AV *rav = (AV *)SvRV (ranges);
        int nranges = av_len (rav) + 1;

        REQ *req = malloc (sizeof (REQ));
        int i;

        if (interval < MIN_INTERVAL)
          interval = MIN_INTERVAL;

        req->id       = newSVsv (id);
        req->interval = interval;
        req->payload  = payload;
        req->nranges  = nranges;
        req->ranges   = (RANGE *)malloc (nranges * sizeof (RANGE));

        while (nranges--)
          {
            SV *sv = *av_fetch (rav, nranges, 1);

            if (!SvROK (sv) || SvTYPE (SvRV (sv)) != SVt_PVAV)
              croak ("address range must be given as arrayref with lo, hi, interval arrayrefs");

            AV *av = (AV *)SvRV (sv);
            RANGE *r = req->ranges + nranges;

            SV *lo = *av_fetch (av, 0, 1);
            SV *hi = *av_fetch (av, 1, 1);

            sv_utf8_downgrade (lo, 0);
            sv_utf8_downgrade (hi, 0);

            memset (&r->lo, 0, sizeof (addr_t));
            memset (&r->hi, 0, sizeof (addr_t));

            if (SvPOKp (lo) && SvPOKp (hi))
              {
                if (SvCUR (lo) != SvCUR (hi))
                  croak ("addresses in range must be of the same size (either 4 or 16 bytes)");

                if (SvCUR (lo) == 4)
                  {
                    r->family = AF_INET;
                    memcpy (sizeof (addr_t) - 4 + (char *)&r->lo, SvPVX (lo), 4);
                    memcpy (sizeof (addr_t) - 4 + (char *)&r->hi, SvPVX (hi), 4);
                  }
                else if (SvCUR (lo) == 16)
                  {
#if IPV6
                    r->family = AF_INET6;
                    memcpy (&r->lo, SvPVX (lo), sizeof (addr_t));
                    memcpy (&r->hi, SvPVX (hi), sizeof (addr_t));
#else
                    croak ("IPv6 not supported in this configuration");
#endif
                  }
                else
                  croak ("addresses in range must be either 4 (IPv4) or 16 (IPV6) bytes in length");
              }
            else if (SvIOK (lo) && SvIOK (hi))
              {
                r->family = AF_INET;

                uint32_t addr;
                addr = htonl (SvUV (lo)); memcpy (sizeof (addr_t) - 4 + (char *)&r->lo, &addr, 4);
                addr = htonl (SvUV (hi)); memcpy (sizeof (addr_t) - 4 + (char *)&r->hi, &addr, 4);
              }
            else
              croak ("addresses in range must be strings with either 4 (IPv4) or 16 (IPv6) octets");

            if (r->family == AF_INET)
              {
                if (icmp4_fd < 0)
                  croak ("AnyEvent::FastPing: IPv4 ping support not available on this system");
              }
            else
              {
                if (icmp6_fd < 0)
                  croak ("AnyEvent::FastPing: IPv6 ping support not available on this system");
              }

            r->interval = SvNV (*av_fetch (av, 2, 1));

            if (r->interval < req->interval)
              r->interval = req->interval;

            r->next = 0.;
          }

        RETVAL = newSVpvn ((char *)&req, sizeof (req));
}
        OUTPUT:
        RETVAL

SV *
_read_res ()
        CODE:
{
        REQ *req;

        if (read (thr_recv [0], &req, sizeof (req)) != sizeof (req))
          RETVAL = &PL_sv_undef;

        RETVAL = req->id;
        free (req->ranges);
        free (req);
}
        OUTPUT:
        RETVAL

void
_recv_icmp4 (...)
        CODE:
{
        char buf [512];
        struct sockaddr_in sa;
        socklen_t sl = sizeof (sa);
        AV *res_av = av_len (cbs) < 0 ? 0 : (AV *)sv_2mortal ((SV *)newAV ());
        tstamp now = NOW ();

        for (;;)
          {
            int len = recvfrom (icmp4_fd, buf, sizeof (buf), MSG_TRUNC, (struct sockaddr *)&sa, &sl);

            if (len <= HDR_SIZE_IP4)
              break;

            IP4HDR *iphdr = (IP4HDR *)buf;

            int hdrlen = (iphdr->version_ihl & 15) * 4;
            int totlen = ntohs (iphdr->tot_len);

            // packet corrupt?
            if (!res_av
                || totlen > len
                || iphdr->protocol != IPPROTO_ICMP
                || hdrlen < HDR_SIZE_IP4 || hdrlen + sizeof (PKT) != totlen)
              continue;

            PKT *pkt = (PKT *)(buf + hdrlen);

            if (pkt->type != ICMP4_ECHO_REPLY
                || pkt->id  != (uint16_t) magic
                || pkt->seq != (uint16_t)~magic
                || !isnormal (pkt->stamp))
              continue;

            AV *av = newAV ();
            av_push (av, newSVpvn ((char *)&sa.sin_addr, 4));
            av_push (av, newSVnv (now - pkt->stamp));
            av_push (av, newSVuv (pkt->payload));

            av_push (res_av, newRV_noinc ((SV *)av));
          }

        if (res_av)
          feed_reply (res_av);
}

void
_recv_icmp6 (...)
        CODE:
{
        struct sockaddr_in6 sa;
        socklen_t sl = sizeof (sa);
        AV *res_av = av_len (cbs) < 0 ? 0 : (AV *)sv_2mortal ((SV *)newAV ());
        PKT pkt;
        tstamp now = NOW ();

        for (;;)
          {
            int len = recvfrom (icmp6_fd, &pkt, sizeof (pkt), MSG_TRUNC, (struct sockaddr *)&sa, &sl);

            if (len != sizeof (PKT))
              break;

            if (!res_av
                || pkt.type != ICMP6_ECHO_REPLY
                || pkt.id  != (uint16_t) magic
                || pkt.seq != (uint16_t)~magic
                || !isnormal (pkt.stamp))
              continue;

            AV *av = newAV ();
            av_push (av, newSVpvn ((char *)&sa.sin6_addr, 16));
            av_push (av, newSVnv (now - pkt.stamp));
            av_push (av, newSVuv (pkt.payload));

            av_push (res_av, newRV_noinc ((SV *)av));
          }

        if (res_av)
          feed_reply (res_av);
}

Revision:	1.4
Committed:	Sun Mar 29 20:07:03 2009 UTC (15 years, 1 month ago) by root
Branch:	MAIN
Changes since 1.3:	+1 -1 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.2	#define _POSIX_C_SOURCE 200112
2			#define _XOPEN_SOURCE 600
3			#define _LARGEFILE64_SOURCE 1
4	root	1.1
5	root	1.3	#ifdef __APPLE__
6	root	1.2	# define IPV6 0
7			#else
8			# define IPV6 1 // if you get compilation problems try to disable IPv6
9			#endif
10	root	1.1
11			#include "EXTERN.h"
12			#include "perl.h"
13			#include "XSUB.h"
14
15			#include <pthread.h>
16
17			#include <math.h>
18			#include <stdio.h>
19			#include <stdlib.h>
20			#include <string.h>
21
22			#include <time.h>
23			#include <poll.h>
24			#include <unistd.h>
25			#include <inttypes.h>
26			#include <fcntl.h>
27			#include <errno.h>
28
29			#include <sys/types.h>
30			#include <sys/time.h>
31			#include <sys/socket.h>
32
33			#include <netinet/in.h>
34			#include <arpa/inet.h>
35
36			#ifdef __linux
37			# include <linux/icmp.h>
38			#endif
39			#if IPV6
40			# include <netinet/icmp6.h>
41			#endif
42
43			#define ICMP4_ECHO 8
44			#define ICMP4_ECHO_REPLY 0
45			#define ICMP6_ECHO 128
46			#define ICMP6_ECHO_REPLY 129
47
48			#define DRAIN_INTERVAL .000001 // how long to wait when sendto returns ENOBUFS, in seconds
49			#define MIN_INTERVAL .000001 // minimum packet send interval, in seconds
50
51			#define HDR_SIZE_IP4 20
52			#define HDR_SIZE_IP6 48
53
54	root	1.4	//TODO: xread/xwrite for atomicity? we currently rely on the fact that the pip buffersize divides exactly by pointer sizes
55	root	1.1
56			typedef uint8_t addr_t[16];
57
58			typedef double tstamp;
59
60			tstamp
61			NOW ()
62			{
63			struct timeval tv;
64			gettimeofday (&tv, 0);
65			return tv.tv_sec + tv.tv_usec * 0.000001;
66			}
67
68			typedef struct {
69			int family;
70			addr_t lo, hi;
71			double interval;
72			tstamp next;
73			} RANGE;
74
75			typedef struct {
76			SV *id;
77			double interval;
78			int nranges;
79			RANGE *ranges;
80			uint32_t payload;
81			} REQ;
82
83			typedef struct {
84			uint8_t version_ihl;
85			uint8_t tos;
86			uint16_t tot_len;
87
88			uint16_t id;
89			uint16_t flags;
90
91			uint8_t ttl;
92			uint8_t protocol;
93			uint16_t cksum;
94
95			uint32_t src;
96			uint32_t dst;
97			} IP4HDR;
98
99			typedef struct {
100			uint8_t version;
101			uint8_t x1, x2, x3;
102
103			uint16_t payload_len;
104			uint8_t nxt_hdr;
105			uint8_t hop_limit;
106
107			uint8_t src[16];
108			uint8_t dst[16];
109			} IP6HDR;
110
111			#define MAGIC 0xca4c
112
113			static uint16_t magic;
114
115			typedef struct {
116			uint8_t type, code;
117			uint16_t cksum;
118			uint16_t id, seq;
119			uint32_t payload;
120			tstamp stamp; // be careful when accessing this
121			} PKT;
122
123			static pthread_t pthrid;
124			static int thr_send[2]; // send to worker
125			static int thr_recv[2]; // receive from worker
126
127			static int icmp4_fd, icmp6_fd;
128
129			static AV *cbs;
130
131			static uint16_t
132			icmp_cksum (void *data, unsigned int len)
133			{
134			register int sum = 0;
135			uint16_t *wp;
136
137			assert (~len & 1);
138
139			for (wp = (uint16_t *)data; len; wp++, len -= 2)
140			sum += *wp;
141
142			sum = (sum >> 16) + (sum & 0xffff); /* add high 16 to low 16 */
143			sum += sum >> 16; /* add carry */
144
145			return ~sum;
146			}
147
148			static void
149			inc_addr (addr_t *addr)
150			{
151			int len = sizeof (addr_t) - 1;
152
153			do
154			{
155			if ((*addr)[len] != 0xff)
156			{
157			++(*addr)[len];
158			break;
159			}
160
161			(*addr)[len] = 0;
162			}
163			while (len--);
164			}
165
166			static void *
167			ping_proc (void *unused)
168			{
169			PKT pkt;
170			struct sockaddr_in sa4;
171			#if IPV6
172			struct sockaddr_in6 sa6;
173			#endif
174
175			memset (&pkt, 0, sizeof (pkt));
176
177			memset (&sa4, 0, sizeof (sa4));
178			sa4.sin_family = AF_INET;
179			sa4.sin_port = 0;
180			#if IPV6
181			memset (&sa6, 0, sizeof (sa6));
182			sa6.sin6_family = AF_INET6;
183			sa6.sin6_port = 0;
184			#endif
185
186			for (;;)
187			{
188			REQ *req;
189			int len = read (thr_send [0], &req, sizeof (req));
190
191			if (!len)
192			pthread_exit (0);
193			else if (len != sizeof (req))
194			{
195			perror ("AnyEvent::FastPing: short reead or read error");
196			pthread_exit ((void *)-1);
197			}
198
199			//TODO: bind to source address
200
201			pkt.code = 0;
202			pkt.id = (uint16_t)magic;
203			pkt.seq = (uint16_t)~magic;
204			pkt.payload = req->payload;
205
206			tstamp now = NOW ();
207			tstamp next = now;
208
209			{
210			int r;
211			for (r = req->nranges; r--; )
212			inc_addr (&req->ranges [r].hi);
213			}
214
215			while (req->nranges)
216			{
217			RANGE *range = req->ranges;
218
219			if (!memcmp (&range->lo, &range->hi, sizeof (addr_t)))
220			req->ranges [0] = req->ranges [--req->nranges];
221			else
222			{
223			// ranges [0] is always the next range to ping
224			tstamp wait = range->next - now;
225
226			// compare with the global frequency limit
227			{
228			tstamp diff = next - now;
229
230			if (wait < diff)
231			wait = diff;
232			else if (range)
233			next = range->next;
234			}
235
236			if (wait > 0.)
237			{
238			struct timespec ts;
239
240			ts.tv_sec = wait;
241			ts.tv_nsec = (wait - ts.tv_sec) * 1000000000.;
242
243			nanosleep (&ts, 0);
244			}
245
246			now = NOW ();
247
248			pkt.stamp = now;
249			pkt.cksum = 0;
250
251			if (range->family == AF_INET)
252			{
253			pkt.type = ICMP4_ECHO;
254			pkt.cksum = icmp_cksum (&pkt, sizeof (pkt));
255
256			memcpy (&sa4.sin_addr,
257			sizeof (addr_t) - sizeof (sa4.sin_addr) + (char *)&range->lo,
258			sizeof (sa4.sin_addr));
259
260			if (sendto (icmp4_fd, &pkt, sizeof (pkt), 0, (struct sockaddr *)&sa4, sizeof (sa4)) > 0)
261			errno = 0;
262			}
263			else
264			{
265			#if IPV6
266			pkt.type = ICMP6_ECHO;
267
268			memcpy (&sa6.sin6_addr,
269			sizeof (addr_t) - sizeof (sa6.sin6_addr) + (char *)&range->lo,
270			sizeof (sa6.sin6_addr));
271
272			if (sendto (icmp6_fd, &pkt, sizeof (pkt), 0, (struct sockaddr *)&sa6, sizeof (sa6)) > 0)
273			errno = 0;
274			#endif
275			}
276
277			if (errno == ENOBUFS)
278			{
279			struct timespec ts;
280
281			ts.tv_sec = 0;
282			ts.tv_nsec = DRAIN_INTERVAL * 1000000000;
283
284			nanosleep (&ts, 0);
285			}
286			else
287			{
288			inc_addr (&range->lo);
289
290			range->next = next;
291			range->next += range->interval;
292			}
293
294			next += req->interval;
295			}
296
297			// make a downheap operation
298			int k = 0;
299			int n = 0;
300			for (;;)
301			{
302			++n;
303			int j = k * 2 + 1;
304
305			if (j >= req->nranges)
306			break;
307			else if (j < req->nranges - 1)
308			if (req->ranges [j].next > req->ranges [j + 1].next)
309			++j;
310
311			if (req->ranges [j].next >= req->ranges [k].next)
312			break;
313
314			RANGE temp = req->ranges [k];
315			req->ranges [k] = req->ranges [j];
316			req->ranges [j] = temp;
317
318			k = j;
319			}
320			}
321
322			write (thr_recv [1], &req, sizeof (req));
323			}
324
325			return 0;
326			}
327
328			static void
329			feed_reply (AV *res_av)
330			{
331			if (av_len (res_av) < 0)
332			return;
333
334			dSP;
335			SV res = sv_2mortal (newRV_inc ((SV )res_av));
336			int i;
337
338			ENTER;
339			SAVETMPS;
340
341			for (i = av_len (cbs) + 1; i--; )
342			{
343			SV cb = av_fetch (cbs, i, 1);
344
345			PUSHMARK (SP);
346			XPUSHs (res);
347			PUTBACK;
348			call_sv (cb, G_DISCARD \| G_VOID);
349			}
350
351			FREETMPS;
352			LEAVE;
353			}
354
355			static void
356			boot ()
357			{
358			sigset_t fullsigset, oldsigset;
359			pthread_attr_t attr;
360
361			if (pipe (thr_send) < 0)
362			croak ("AnyEvent::FastPing: unable to create send pipe");
363
364			if (pipe (thr_recv) < 0)
365			croak ("AnyEvent::FastPing: unable to create receive pipe");
366
367			icmp4_fd = socket (AF_INET, SOCK_RAW, IPPROTO_ICMP);
368	root	1.2	fcntl (icmp4_fd, F_SETFL, O_NONBLOCK);
369	root	1.1	#ifdef ICMP_FILTER
370			{
371			struct icmp_filter oval;
372			oval.data = 0xffffffff & ~(1 << ICMP4_ECHO_REPLY);
373			setsockopt (icmp4_fd, SOL_RAW, ICMP_FILTER, &oval, sizeof oval);
374			}
375			#endif
376
377			#if IPV6
378			icmp6_fd = socket (AF_INET6, SOCK_RAW, IPPROTO_ICMPV6);
379	root	1.2	fcntl (icmp6_fd, F_SETFL, O_NONBLOCK);
380	root	1.1	# ifdef ICMP6_FILTER
381			{
382			struct icmp6_filter oval;
383			ICMP6_FILTER_SETBLOCKALL (&oval);
384			ICMP6_FILTER_SETPASS (ICMP6_ECHO_REPLY, &oval);
385			setsockopt (icmp6_fd, IPPROTO_ICMPV6, ICMP6_FILTER, &oval, sizeof oval);
386			}
387			# endif
388			#endif
389
390			pthread_attr_init (&attr);
391			pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
392			#ifdef PTHREAD_SCOPE_PROCESS
393			pthread_attr_setscope (&attr, PTHREAD_SCOPE_PROCESS);
394			#endif
395
396			sigfillset (&fullsigset);
397
398			pthread_sigmask (SIG_SETMASK, &fullsigset, &oldsigset);
399
400			if (pthread_create (&pthrid, &attr, ping_proc, 0))
401			croak ("AnyEvent::FastPing: unable to create pinger thread");
402
403			pthread_sigmask (SIG_SETMASK, &oldsigset, 0);
404
405			sv_setiv (get_sv ("AnyEvent::FastPing::THR_REQ_FD", 1), thr_send [1]);
406			sv_setiv (get_sv ("AnyEvent::FastPing::THR_RES_FD", 1), thr_recv [0]);
407
408			sv_setiv (get_sv ("AnyEvent::FastPing::ICMP4_FD", 1), icmp4_fd);
409			sv_setiv (get_sv ("AnyEvent::FastPing::ICMP6_FD", 1), icmp6_fd);
410			}
411
412			MODULE = AnyEvent::FastPing PACKAGE = AnyEvent::FastPing
413
414			BOOT:
415			{
416			HV *stash = gv_stashpv ("AnyEvent::FastPing", 1);
417
418			cbs = get_av ("AnyEvent::FastPing::CB", 1);
419			magic = getpid () ^ MAGIC;
420
421			boot ();
422
423			newCONSTSUB (stash, "ipv4_supported", newSViv (icmp4_fd >= 0));
424			newCONSTSUB (stash, "ipv6_supported", newSViv (icmp6_fd >= 0));
425
426			newCONSTSUB (stash, "icmp4_pktsize", newSViv (HDR_SIZE_IP4 + sizeof (PKT)));
427			newCONSTSUB (stash, "icmp6_pktsize", newSViv (HDR_SIZE_IP6 + sizeof (PKT)));
428			}
429
430			PROTOTYPES: DISABLE
431
432			SV *
433			_req_icmp_ping (SV ranges, NV interval, U32 payload, SV id)
434			CODE:
435			{
436			if (!SvROK (ranges) \|\| SvTYPE (SvRV (ranges)) != SVt_PVAV)
437			croak ("address ranges must be given as arrayref with lo, hi pairs");
438
439			AV rav = (AV )SvRV (ranges);
440			int nranges = av_len (rav) + 1;
441
442			REQ *req = malloc (sizeof (REQ));
443			int i;
444
445			if (interval < MIN_INTERVAL)
446			interval = MIN_INTERVAL;
447
448			req->id = newSVsv (id);
449			req->interval = interval;
450			req->payload = payload;
451			req->nranges = nranges;
452			req->ranges = (RANGE )malloc (nranges sizeof (RANGE));
453
454			while (nranges--)
455			{
456			SV sv = av_fetch (rav, nranges, 1);
457
458			if (!SvROK (sv) \|\| SvTYPE (SvRV (sv)) != SVt_PVAV)
459			croak ("address range must be given as arrayref with lo, hi, interval arrayrefs");
460
461			AV av = (AV )SvRV (sv);
462			RANGE *r = req->ranges + nranges;
463
464			SV lo = av_fetch (av, 0, 1);
465			SV hi = av_fetch (av, 1, 1);
466
467			sv_utf8_downgrade (lo, 0);
468			sv_utf8_downgrade (hi, 0);
469
470			memset (&r->lo, 0, sizeof (addr_t));
471			memset (&r->hi, 0, sizeof (addr_t));
472
473			if (SvPOKp (lo) && SvPOKp (hi))
474			{
475			if (SvCUR (lo) != SvCUR (hi))
476			croak ("addresses in range must be of the same size (either 4 or 16 bytes)");
477
478			if (SvCUR (lo) == 4)
479			{
480			r->family = AF_INET;
481			memcpy (sizeof (addr_t) - 4 + (char *)&r->lo, SvPVX (lo), 4);
482			memcpy (sizeof (addr_t) - 4 + (char *)&r->hi, SvPVX (hi), 4);
483			}
484			else if (SvCUR (lo) == 16)
485			{
486			#if IPV6
487			r->family = AF_INET6;
488			memcpy (&r->lo, SvPVX (lo), sizeof (addr_t));
489			memcpy (&r->hi, SvPVX (hi), sizeof (addr_t));
490			#else
491			croak ("IPv6 not supported in this configuration");
492			#endif
493			}
494			else
495			croak ("addresses in range must be either 4 (IPv4) or 16 (IPV6) bytes in length");
496			}
497			else if (SvIOK (lo) && SvIOK (hi))
498			{
499			r->family = AF_INET;
500
501			uint32_t addr;
502			addr = htonl (SvUV (lo)); memcpy (sizeof (addr_t) - 4 + (char *)&r->lo, &addr, 4);
503			addr = htonl (SvUV (hi)); memcpy (sizeof (addr_t) - 4 + (char *)&r->hi, &addr, 4);
504			}
505			else
506			croak ("addresses in range must be strings with either 4 (IPv4) or 16 (IPv6) octets");
507
508			if (r->family == AF_INET)
509			{
510			if (icmp4_fd < 0)
511			croak ("AnyEvent::FastPing: IPv4 ping support not available on this system");
512			}
513			else
514			{
515			if (icmp6_fd < 0)
516			croak ("AnyEvent::FastPing: IPv6 ping support not available on this system");
517			}
518
519			r->interval = SvNV (*av_fetch (av, 2, 1));
520
521			if (r->interval < req->interval)
522			r->interval = req->interval;
523
524			r->next = 0.;
525			}
526
527			RETVAL = newSVpvn ((char *)&req, sizeof (req));
528			}
529			OUTPUT:
530			RETVAL
531
532			SV *
533			_read_res ()
534			CODE:
535			{
536			REQ *req;
537
538			if (read (thr_recv [0], &req, sizeof (req)) != sizeof (req))
539			RETVAL = &PL_sv_undef;
540
541			RETVAL = req->id;
542			free (req->ranges);
543			free (req);
544			}
545			OUTPUT:
546			RETVAL
547
548			void
549			_recv_icmp4 (...)
550			CODE:
551			{
552			char buf [512];
553			struct sockaddr_in sa;
554			socklen_t sl = sizeof (sa);
555			AV res_av = av_len (cbs) < 0 ? 0 : (AV )sv_2mortal ((SV *)newAV ());
556			tstamp now = NOW ();
557
558			for (;;)
559			{
560	root	1.2	int len = recvfrom (icmp4_fd, buf, sizeof (buf), MSG_TRUNC, (struct sockaddr *)&sa, &sl);
561	root	1.1
562			if (len <= HDR_SIZE_IP4)
563			break;
564
565			IP4HDR iphdr = (IP4HDR )buf;
566
567			int hdrlen = (iphdr->version_ihl & 15) * 4;
568			int totlen = ntohs (iphdr->tot_len);
569
570			// packet corrupt?
571			if (!res_av
572			\|\| totlen > len
573			\|\| iphdr->protocol != IPPROTO_ICMP
574			\|\| hdrlen < HDR_SIZE_IP4 \|\| hdrlen + sizeof (PKT) != totlen)
575			continue;
576
577			PKT pkt = (PKT )(buf + hdrlen);
578
579			if (pkt->type != ICMP4_ECHO_REPLY
580			\|\| pkt->id != (uint16_t) magic
581			\|\| pkt->seq != (uint16_t)~magic
582			\|\| !isnormal (pkt->stamp))
583			continue;
584
585			AV *av = newAV ();
586			av_push (av, newSVpvn ((char *)&sa.sin_addr, 4));
587			av_push (av, newSVnv (now - pkt->stamp));
588			av_push (av, newSVuv (pkt->payload));
589
590			av_push (res_av, newRV_noinc ((SV *)av));
591			}
592
593			if (res_av)
594			feed_reply (res_av);
595			}
596
597			void
598			_recv_icmp6 (...)
599			CODE:
600			{
601			struct sockaddr_in6 sa;
602			socklen_t sl = sizeof (sa);
603			AV res_av = av_len (cbs) < 0 ? 0 : (AV )sv_2mortal ((SV *)newAV ());
604			PKT pkt;
605			tstamp now = NOW ();
606
607			for (;;)
608			{
609	root	1.2	int len = recvfrom (icmp6_fd, &pkt, sizeof (pkt), MSG_TRUNC, (struct sockaddr *)&sa, &sl);
610	root	1.1
611			if (len != sizeof (PKT))
612			break;
613
614			if (!res_av
615			\|\| pkt.type != ICMP6_ECHO_REPLY
616			\|\| pkt.id != (uint16_t) magic
617			\|\| pkt.seq != (uint16_t)~magic
618			\|\| !isnormal (pkt.stamp))
619			continue;
620
621			AV *av = newAV ();
622			av_push (av, newSVpvn ((char *)&sa.sin6_addr, 16));
623			av_push (av, newSVnv (now - pkt.stamp));
624			av_push (av, newSVuv (pkt.payload));
625
626			av_push (res_av, newRV_noinc ((SV *)av));
627			}
628
629			if (res_av)
630			feed_reply (res_av);
631			}
632