X-Git-Url: http://git.pk910.de/?p=ircu2.10.12-pk.git;a=blobdiff_plain;f=ircd%2Fos_generic.c;fp=ircd%2Fos_generic.c;h=9ddb3c40bd686bb83124e62485cc4a2f3581271a;hp=0000000000000000000000000000000000000000;hb=0400a5a6479398d82526785c18c0df8bc8b92dce;hpb=d17e10da972ce5776c60b4c317267c6abe0e1ead

diff --git a/ircd/os_generic.c b/ircd/os_generic.c
new file mode 100644
index 0000000..9ddb3c4
--- /dev/null
+++ b/ircd/os_generic.c
@@ -0,0 +1,714 @@
+/*
+ * IRC - Internet Relay Chat, ircd/os_generic.c
+ * Copyright (C) 1999 Thomas Helvey
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 1, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+/** @file
+ * @brief Implementation of OS-dependent operations.
+ * @version $Id$
+ */
+#include "config.h"
+
+#ifdef IRCU_SOLARIS
+/* Solaris requires C99 support for SUSv3, but C99 support breaks other
+ * parts of the build.  So fall back to SUSv2, but request IPv6 support
+ * by defining __EXTENSIONS__.
+ */
+#define _XOPEN_SOURCE   500
+#define __EXTENSIONS__  1
+#elif defined(__FreeBSD__) && __FreeBSD__ >= 5
+/* FreeBSD 6.0 requires SUSv3 to support IPv6 -- but if you ask for
+ * that specifically (by defining _XOPEN_SOURCE to anything at all),
+ * they cleverly hide IPPROTO_IPV6.  If you don't ask for anything,
+ * they give you everything.
+ */
+#else
+#define _XOPEN_SOURCE   600
+#endif
+
+#include "ircd_osdep.h"
+#include "msgq.h"
+#include "ircd_log.h"
+#include "res.h"
+#include "s_bsd.h"
+#include "sys.h"
+
+/* Include file dependency notes:
+ * FreeBSD requires struct timeval from sys/time.h before struct
+ * rusage in sys/resource.h.
+ * Solaris requires sys/time.h before struct rusage (indirectly) in
+ * netinet/in.h.
+ */
+/* #include <assert.h> -- Now using assert in ircd_log.h */
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/types.h>
+#include <sys/time.h>
+#include <netinet/in.h>
+#include <sys/resource.h>
+#include <sys/socket.h>
+#include <sys/uio.h>
+
+#if HAVE_SYS_PARAM_H
+#include <sys/param.h>
+#endif
+
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+#if defined(IPV6_BINDV6ONLY) &&!defined(IPV6_V6ONLY)
+# define IPV6_V6ONLY IPV6_BINDV6ONLY
+#endif
+
+#ifndef IOV_MAX
+#define IOV_MAX 16	/**< minimum required length of an iovec array */
+#endif
+
+#ifdef HPUX
+#include <sys/syscall.h>
+#define getrusage(a,b) syscall(SYS_GETRUSAGE, a, b)
+#endif
+
+static int is_blocked(int error)
+{
+  return EWOULDBLOCK == error
+#ifdef ENOMEM
+    || ENOMEM == error
+#endif
+#ifdef ENOBUFS
+    || ENOBUFS == error
+#endif
+    || EAGAIN == error;
+}
+
+static void sockaddr_in_to_irc(const struct sockaddr_in *v4,
+                               struct irc_sockaddr *irc)
+{
+    memset(&irc->addr, 0, 5*sizeof(int16_t));
+    irc->addr.in6_16[5] = 0xffff;
+    memcpy(&irc->addr.in6_16[6], &v4->sin_addr, sizeof(v4->sin_addr));
+    irc->port = ntohs(v4->sin_port);
+}
+
+
+#ifdef IPV6
+/** Native socket address type. */
+#define sockaddr_native sockaddr_in6
+/** Field name inside sockaddr_native to find address family. */
+#define sn_family sin6_family
+
+/** Convert native socket address to IRC format.
+ * @param[in] v6 Native socket address.
+ * @param[out] irc IRC format socket address.
+ */
+void sockaddr_to_irc(const struct sockaddr_in6 *v6, struct irc_sockaddr *irc)
+{
+    if (v6->sin6_family == AF_INET6) {
+        memcpy(&irc->addr.in6_16[0], &v6->sin6_addr, sizeof(v6->sin6_addr));
+        irc->port = ntohs(v6->sin6_port);
+    }
+    else if (v6->sin6_family == AF_INET) {
+        sockaddr_in_to_irc((struct sockaddr_in *)v6, irc);
+    }
+    else assert(0 && "Unhandled native address family");
+}
+
+/** Convert IRC socket address to native format.
+ * @param[out] v6 Native socket address.
+ * @param[in] irc IRC socket address.
+ * @param[in] compat_fd If non-negative, an FD specifying address family.
+ * @return Length of address written to \a v6.
+ */
+int sockaddr_from_irc(struct sockaddr_in6 *v6, const struct irc_sockaddr *irc, int compat_fd, int family)
+{
+    struct sockaddr_in6 sin6;
+    socklen_t slen;
+
+    assert(irc != 0);
+    slen = sizeof(sin6);
+    if (family) {
+        /* accept whatever user specified */
+    } else if ((0 <= compat_fd)
+        && (0 == getsockname(compat_fd, (struct sockaddr*)&sin6, &slen)))
+        family = sin6.sin6_family;
+    else if ((irc == &VirtualHost_v4) || irc_in_addr_is_ipv4(&irc->addr))
+        family = AF_INET;
+    else
+        family = AF_INET6;
+
+    memset(v6, 0, sizeof(*v6));
+    if (family == AF_INET) {
+        struct sockaddr_in *v4 = (struct sockaddr_in*)v6;
+        v4->sin_family = AF_INET;
+        memcpy(&v4->sin_addr, &irc->addr.in6_16[6], sizeof(v4->sin_addr));
+        v4->sin_port = htons(irc->port);
+        return sizeof(*v4);
+    }
+    else {
+        v6->sin6_family = AF_INET6;
+        memcpy(&v6->sin6_addr, &irc->addr.in6_16[0], sizeof(v6->sin6_addr));
+        v6->sin6_port = htons(irc->port);
+        return sizeof(*v6);
+    }
+}
+
+#else
+#define sockaddr_native sockaddr_in
+#define sn_family sin_family
+#define sockaddr_to_irc sockaddr_in_to_irc
+
+int sockaddr_from_irc(struct sockaddr_in *v4, const struct irc_sockaddr *irc, int compat_fd, int family)
+{
+    assert(irc != 0);
+    memset(v4, 0, sizeof(*v4));
+    v4->sin_family = AF_INET;
+    if (irc) {
+        assert(!irc->addr.in6_16[0] && !irc->addr.in6_16[1] && !irc->addr.in6_16[2] && !irc->addr.in6_16[3] && !irc->addr.in6_16[4] && (!irc->addr.in6_16[5] || irc->addr.in6_16[5] == 0xffff));
+        memcpy(&v4->sin_addr, &irc->addr.in6_16[6], sizeof(v4->sin_addr));
+        v4->sin_port = htons(irc->port);
+    }
+    (void)compat_fd; (void)family;
+    return sizeof(*v4);
+}
+
+#endif
+
+#ifdef DEBUGMODE
+/** Send resource usage information to an enumerator function.
+ * @param[in] cptr Client requesting information.
+ * @param[in] uptime Wall time in seconds since the server started.
+ * @param[in] enumerator Function to call to send a line to \a cptr.
+ * @return Zero if some usage reports could not be sent, non-zero on success.
+ */
+int os_get_rusage(struct Client *cptr, int uptime, EnumFn enumerator)
+{
+#ifdef HAVE_GETRUSAGE
+  char buf[256];
+  struct rusage rus;
+  time_t secs;
+
+#ifdef  hz
+#  define hzz hz
+#else
+#  ifdef HZ
+#    define hzz HZ
+#  else
+  int hzz = 1;
+#  ifdef HPUX
+  hzz = sysconf(_SC_CLK_TCK);
+#  endif
+#endif
+#endif
+
+  assert(0 != enumerator);
+  if (getrusage(RUSAGE_SELF, &rus) == -1)
+    return 0;
+
+  secs = rus.ru_utime.tv_sec + rus.ru_stime.tv_sec;
+  if (secs == 0)
+    secs = 1;
+
+  sprintf(buf, "CPU Secs %ld:%ld User %ld:%ld System %ld:%ld",
+          (long)(secs / 60), (long)(secs % 60),
+          rus.ru_utime.tv_sec / 60, rus.ru_utime.tv_sec % 60,
+          rus.ru_stime.tv_sec / 60, rus.ru_stime.tv_sec % 60);
+  (*enumerator)(cptr, buf);
+
+  sprintf(buf, "RSS %ld ShMem %ld Data %ld Stack %ld",
+          rus.ru_maxrss,
+          rus.ru_ixrss / (uptime * hzz), rus.ru_idrss / (uptime * hzz),
+          rus.ru_isrss / (uptime * hzz));
+  (*enumerator)(cptr, buf);
+
+  sprintf(buf, "Swaps %ld Reclaims %ld Faults %ld",
+          rus.ru_nswap, rus.ru_minflt, rus.ru_majflt);
+  (*enumerator)(cptr, buf);
+
+  sprintf(buf, "Block in %ld out %ld", rus.ru_inblock, rus.ru_oublock);
+  (*enumerator)(cptr, buf);
+
+  sprintf(buf, "Msg Rcv %ld Send %ld", rus.ru_msgrcv, rus.ru_msgsnd);
+  (*enumerator)(cptr, buf);
+
+  sprintf(buf, "Signals %ld Context Vol. %ld Invol %ld",
+          rus.ru_nsignals, rus.ru_nvcsw, rus.ru_nivcsw);
+  (*enumerator)(cptr, buf);
+
+#else /* HAVE_GETRUSAGE */
+#if HAVE_TIMES
+  char buf[256];
+  struct tms tmsbuf;
+  time_t secs, mins;
+  int hzz = 1, ticpermin;
+  int umin, smin, usec, ssec;
+
+  assert(0 != enumerator);
+#ifdef HPUX
+  hzz = sysconf(_SC_CLK_TCK);
+#endif
+  ticpermin = hzz * 60;
+
+  umin = tmsbuf.tms_utime / ticpermin;
+  usec = (tmsbuf.tms_utime % ticpermin) / (float)hzz;
+  smin = tmsbuf.tms_stime / ticpermin;
+  ssec = (tmsbuf.tms_stime % ticpermin) / (float)hzz;
+  secs = usec + ssec;
+  mins = (secs / 60) + umin + smin;
+  secs %= hzz;
+
+  if (times(&tmsbuf) == -1)
+    return 0;
+  secs = tmsbuf.tms_utime + tmsbuf.tms_stime;
+
+  sprintf(buf, "CPU Secs %d:%d User %d:%d System %d:%d", 
+          mins, secs, umin, usec, smin, ssec);
+  (*enumerator)(cptr, buf);
+#endif /* HAVE_TIMES */
+#endif /* HAVE_GETRUSAGE */
+  return 1;
+}
+#endif
+
+/** Look up the most recent socket error for a socket file descriptor.
+ * @param[in] fd File descriptor to check.
+ * @return Error code from the socket, or 0 if the OS does not support this.
+ */
+int os_get_sockerr(int fd)
+{
+  int    err = 0;
+#if defined(SO_ERROR)
+  unsigned int len = sizeof(err);
+  getsockopt(fd, SOL_SOCKET, SO_ERROR, &err, &len);
+#endif
+  return err;
+}
+
+/** Set a file descriptor to non-blocking mode.
+ * @param[in] fd %Socket file descriptor.
+ * @return Non-zero on success, or zero on failure.
+ */
+int os_set_nonblocking(int fd)
+{
+  int res;
+#ifndef NBLOCK_SYSV
+  int nonb = 0;
+#endif
+
+  /*
+   * NOTE: consult ALL your relevant manual pages *BEFORE* changing
+   * these ioctl's. There are quite a few variations on them,
+   * as can be seen by the PCS one. They are *NOT* all the same.
+   * Heed this well. - Avalon.
+   */
+#ifdef  NBLOCK_POSIX
+  nonb |= O_NONBLOCK;
+#endif
+#ifdef  NBLOCK_BSD
+  nonb |= O_NDELAY;
+#endif
+#ifdef  NBLOCK_SYSV
+  /* This portion of code might also apply to NeXT. -LynX */
+  res = 1;
+
+  if (ioctl(fd, FIONBIO, &res) == -1)
+    return 0;
+#else
+  if ((res = fcntl(fd, F_GETFL, 0)) == -1)
+    return 0;
+  else if (fcntl(fd, F_SETFL, res | nonb) == -1)
+    return 0;
+#endif
+  return 1;
+}
+
+/** Mark a socket's address as reusable.
+ * @param[in] fd %Socket file descriptor to manipulate.
+ * @return Non-zero on success, or zero on failure.
+ */
+int os_set_reuseaddr(int fd)
+{
+  unsigned int opt = 1;
+  return (0 == setsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
+                          (const char*) &opt, sizeof(opt)));
+}
+
+/** Set a socket's send and receive buffer sizes.
+ * @param[in] fd %Socket file descriptor to manipulate.
+ * @param[in] ssize New send buffer size.
+ * @param[in] rsize New receive buffer size.
+ * @return Non-zero on success, or zero on failure.
+ */
+int os_set_sockbufs(int fd, unsigned int ssize, unsigned int rsize)
+{
+  unsigned int sopt = ssize;
+  unsigned int ropt = rsize;
+  return (0 == setsockopt(fd, SOL_SOCKET, SO_RCVBUF,
+                          (const char*) &ropt, sizeof(ropt)) &&
+          0 == setsockopt(fd, SOL_SOCKET, SO_SNDBUF,
+                          (const char*) &sopt, sizeof(sopt)));
+}
+
+/** Set a socket's "type of service" value.
+ * @param[in] fd %Socket file descriptor to manipulate.
+ * @param[in] tos New type of service value to use.
+ * @return Non-zero on success, or zero on failure.
+ */
+int os_set_tos(int fd,int tos)
+{
+#if defined(IP_TOS) && defined(IPPROTO_IP)
+  unsigned int opt = tos;
+  return (0 == setsockopt(fd, IPPROTO_IP, IP_TOS, &opt, sizeof(opt)));
+#else
+  return 1;
+#endif
+}
+
+/** Disable IP options on a socket.
+ * @param[in] fd %Socket file descriptor to manipulate.
+ * @return Non-zero on success, or zero on failure.
+ */
+int os_disable_options(int fd)
+{
+#if defined(IP_OPTIONS) && defined(IPPROTO_IP)
+  return (0 == setsockopt(fd, IPPROTO_IP, IP_OPTIONS, NULL, 0));
+#else
+  return 1;
+#endif
+}
+
+/*
+ * Try and find the correct name to use with getrlimit() for setting the max.
+ * number of files allowed to be open by this process.
+ */
+#ifdef RLIMIT_FDMAX
+#define RLIMIT_FD_MAX   RLIMIT_FDMAX
+#else
+#ifdef RLIMIT_NOFILE
+#define RLIMIT_FD_MAX RLIMIT_NOFILE
+#else
+#ifdef RLIMIT_OPEN_MAX
+#define RLIMIT_FD_MAX RLIMIT_OPEN_MAX
+#else
+#undef RLIMIT_FD_MAX
+#endif
+#endif
+#endif
+
+/** Set file descriptor limit for the process.
+ * @param[in] max_descriptors Ideal number of file descriptors.
+ * @return Zero on success; -1 on error; positive number of possible
+ * file descriptors if \a max_descriptors is too high.
+ */
+int os_set_fdlimit(unsigned int max_descriptors)
+{
+#if defined(HAVE_SETRLIMIT) && defined(RLIMIT_FD_MAX)
+  struct rlimit limit;
+
+  if (!getrlimit(RLIMIT_FD_MAX, &limit)) {
+    if (limit.rlim_max < max_descriptors)
+      return limit.rlim_max;
+    limit.rlim_cur = limit.rlim_max;    /* make soft limit the max */
+    return setrlimit(RLIMIT_FD_MAX, &limit);
+  }
+#endif /* defined(HAVE_SETRLIMIT) && defined(RLIMIT_FD_MAX) */
+  return 0;
+}
+
+/** Attempt to read from a non-blocking socket.
+ * @param[in] fd File descriptor to read from.
+ * @param[out] buf Output buffer to read into.
+ * @param[in] length Number of bytes to read.
+ * @param[out] count_out Receives number of bytes actually read.
+ * @return An IOResult value indicating status.
+ */
+IOResult os_recv_nonb(int fd, char* buf, unsigned int length,
+                 unsigned int* count_out)
+{
+  int res;
+  assert(0 != buf);
+  assert(0 != count_out);
+
+  if (0 < (res = recv(fd, buf, length, 0))) {
+    *count_out = (unsigned) res;
+    return IO_SUCCESS;
+  } else if (res == 0) {
+    *count_out = 0;
+    errno = 0; /* or ECONNRESET? */
+    return IO_FAILURE;
+  } else {
+    *count_out = 0;
+    return is_blocked(errno) ? IO_BLOCKED : IO_FAILURE;
+  }
+}
+
+/** Attempt to read from a non-blocking UDP socket.
+ * @param[in] fd File descriptor to read from.
+ * @param[out] buf Output buffer to read into.
+ * @param[in] length Number of bytes to read.
+ * @param[out] length_out Receives number of bytes actually read.
+ * @param[out] addr_out Peer address that sent the message.
+ * @return An IOResult value indicating status.
+ */
+IOResult os_recvfrom_nonb(int fd, char* buf, unsigned int length,
+                          unsigned int* length_out,
+                          struct irc_sockaddr* addr_out)
+{
+  struct sockaddr_native addr;
+  unsigned int len = sizeof(addr);
+  int    res;
+  assert(0 != buf);
+  assert(0 != length_out);
+  assert(0 != addr_out);
+
+  res = recvfrom(fd, buf, length, 0, (struct sockaddr*) &addr, &len);
+  if (-1 < res) {
+    sockaddr_to_irc(&addr, addr_out);
+    *length_out = res;
+    return IO_SUCCESS;
+  } else {
+    *length_out = 0;
+    return is_blocked(errno) ? IO_BLOCKED : IO_FAILURE;
+  }
+}
+
+/** Attempt to write on a non-blocking UDP socket.
+ * @param[in] fd File descriptor to write to.
+ * @param[in] buf Output buffer to send from.
+ * @param[in] length Number of bytes to write.
+ * @param[out] count_out Receives number of bytes actually written.
+ * @param[in] flags Flags for call to sendto().
+ * @param[in] peer Destination address of the message.
+ * @return An IOResult value indicating status.
+ */
+IOResult os_sendto_nonb(int fd, const char* buf, unsigned int length,
+                        unsigned int* count_out, unsigned int flags,
+                        const struct irc_sockaddr* peer)
+{
+  struct sockaddr_native addr;
+  int res, size;
+  assert(0 != buf);
+
+  size = sockaddr_from_irc(&addr, peer, fd, 0);
+  assert((addr.sn_family == AF_INET) == irc_in_addr_is_ipv4(&peer->addr));
+  if (-1 < (res = sendto(fd, buf, length, flags, (struct sockaddr*)&addr, size))) {
+    if (count_out)
+      *count_out = (unsigned) res;
+    return IO_SUCCESS;
+  } else {
+    if (count_out)
+      *count_out = 0;
+    return is_blocked(errno) ? IO_BLOCKED : IO_FAILURE;
+  }
+}
+
+/** Attempt to write on a connected socket.
+ * @param[in] fd File descriptor to write to.
+ * @param[in] buf Output buffer to send from.
+ * @param[in] length Number of bytes to write.
+ * @param[out] count_out Receives number of bytes actually written.
+ * @return An IOResult value indicating status.
+ */
+IOResult os_send_nonb(int fd, const char* buf, unsigned int length, 
+                 unsigned int* count_out)
+{
+  int res;
+  assert(0 != buf);
+  assert(0 != count_out);
+
+  if (-1 < (res = send(fd, buf, length, 0))) {
+    *count_out = (unsigned) res;
+    return IO_SUCCESS;
+  } else {
+    *count_out = 0;
+    return is_blocked(errno) ? IO_BLOCKED : IO_FAILURE;
+  }
+}
+
+/** Attempt a vectored write on a connected socket.
+ * @param[in] fd File descriptor to write to.
+ * @param[in] buf Message queue to send from.
+ * @param[out] count_in Number of bytes mapped from \a buf.
+ * @param[out] count_out Receives number of bytes actually written.
+ * @return An IOResult value indicating status.
+ */
+IOResult os_sendv_nonb(int fd, struct MsgQ* buf, unsigned int* count_in,
+		       unsigned int* count_out)
+{
+  int res;
+  int count;
+  struct iovec iov[IOV_MAX];
+
+  assert(0 != buf);
+  assert(0 != count_in);
+  assert(0 != count_out);
+
+  *count_in = 0;
+  count = msgq_mapiov(buf, iov, IOV_MAX, count_in);
+
+  if (-1 < (res = writev(fd, iov, count))) {
+    *count_out = (unsigned) res;
+    return IO_SUCCESS;
+  } else {
+    *count_out = 0;
+    return is_blocked(errno) ? IO_BLOCKED : IO_FAILURE;
+  }
+}
+
+/** Open a TCP or UDP socket on a particular address.
+ * @param[in] local Local address to bind to.
+ * @param[in] type SOCK_STREAM or SOCK_DGRAM.
+ * @param[in] port_name Port name (used in error diagnostics).
+ * @param[in] family A specific address family to use, or 0 for automatic.
+ * @return Bound descriptor, or -1 on error.
+ */
+int os_socket(const struct irc_sockaddr* local, int type, const char* port_name, int family)
+{
+  struct sockaddr_native addr;
+  int size, fd;
+
+  assert(local != 0);
+  size = sockaddr_from_irc(&addr, local, -1, family);
+  fd = socket(addr.sn_family, type, 0);
+  if (fd < 0) {
+    report_error(SOCKET_ERROR_MSG, port_name, errno);
+    return -1;
+  }
+  if (fd > MAXCLIENTS - 1) {
+    report_error(CONNLIMIT_ERROR_MSG, port_name, 0);
+    close(fd);
+    return -1;
+  }
+  if (!os_set_reuseaddr(fd)) {
+    report_error(REUSEADDR_ERROR_MSG, port_name, errno);
+    close(fd);
+    return -1;
+  }
+  if (!os_set_nonblocking(fd)) {
+    report_error(NONB_ERROR_MSG, port_name, errno);
+    close(fd);
+    return -1;
+  }
+  if (local) {
+#if defined(IPV6_V6ONLY)
+    int on = 1;
+    if (family == AF_INET6 && irc_in_addr_unspec(&local->addr))
+      setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on));
+#endif
+    if (bind(fd, (struct sockaddr*)&addr, size)) {
+      report_error(BIND_ERROR_MSG, port_name, errno);
+      close(fd);
+      return -1;
+    }
+  }
+  return fd;
+}
+
+/** Accept a connection on a socket.
+ * @param[in] fd Listening file descriptor.
+ * @param[out] peer Peer address of connection.
+ * @return File descriptor for accepted connection.
+ */
+int os_accept(int fd, struct irc_sockaddr* peer)
+{
+  struct sockaddr_native addr;
+  socklen_t addrlen;
+  int new_fd;
+
+  addrlen = sizeof(addr);
+  new_fd = accept(fd, (struct sockaddr*)&addr, &addrlen);
+  if (new_fd < 0)
+    memset(peer, 0, sizeof(*peer));
+  else
+    sockaddr_to_irc(&addr, peer);
+  return new_fd;
+}
+
+/** Start a non-blocking connection.
+ * @param[in] fd Disconnected file descriptor.
+ * @param[in] sin Target address for connection.
+ * @return IOResult code indicating status.
+ */
+IOResult os_connect_nonb(int fd, const struct irc_sockaddr* sin)
+{
+  struct sockaddr_native addr;
+  int size;
+
+  size = sockaddr_from_irc(&addr, sin, fd, 0);
+  if (0 == connect(fd, (struct sockaddr*) &addr, size))
+    return IO_SUCCESS;
+  else if (errno == EINPROGRESS)
+    return IO_BLOCKED;
+  else
+    return IO_FAILURE;
+}
+
+/** Get local address of a socket.
+ * @param[in] fd File descriptor to operate on.
+ * @param[out] sin_out Receives local socket address.
+ * @return Non-zero on success; zero on error.
+ */
+int os_get_sockname(int fd, struct irc_sockaddr* sin_out)
+{
+  struct sockaddr_native addr;
+  unsigned int len = sizeof(addr);
+
+  assert(0 != sin_out);
+  if (getsockname(fd, (struct sockaddr*) &addr, &len))
+    return 0;
+  sockaddr_to_irc(&addr, sin_out);
+  return 1;
+}
+
+/** Get remote address of a socket.
+ * @param[in] fd File descriptor to operate on.
+ * @param[out] sin_out Receives remote socket address.
+ * @return Non-zero on success; zero on error.
+ */
+int os_get_peername(int fd, struct irc_sockaddr* sin_out)
+{
+  struct sockaddr_native addr;
+  unsigned int len = sizeof(addr);
+
+  assert(0 != sin_out);
+  if (getpeername(fd, (struct sockaddr*) &addr, &len))
+    return 0;
+  sockaddr_to_irc(&addr, sin_out);
+  return 1;
+}
+
+/** Start listening on a socket.
+ * @param[in] fd Disconnected file descriptor.
+ * @param[in] backlog Maximum number of un-accept()ed connections to keep.
+ * @return Non-zero on success; zero on error.
+ */
+int os_set_listen(int fd, int backlog)
+{
+  return (0 == listen(fd, backlog));
+}
+
+/** Allocate a connected pair of local sockets.
+ * @param[out] sv Array of two file descriptors.
+ * @return Zero on success; non-zero number on error.
+ */
+int os_socketpair(int sv[2])
+{
+    return socketpair(AF_UNIX, SOCK_STREAM, 0, sv);
+}