thirdparty/uuid/gen_uuid.c - nifi-minifi-cpp - Git at Google

 /*
  * gen_uuid.c --- generate a DCE-compatible uuid
  *
  * Copyright (C) 1996, 1997, 1998, 1999 Theodore Ts'o.
  *
  * %Begin-Header%
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, and the entire permission notice in its entirety,
  *    including the disclaimer of warranties.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  * 3. The name of the author may not be used to endorse or promote
  *    products derived from this software without specific prior
  *    written permission.
  *
  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ALL OF
  * WHICH ARE HEREBY DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE
  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
  * USE OF THIS SOFTWARE, EVEN IF NOT ADVISED OF THE POSSIBILITY OF SUCH
  * DAMAGE.
  * %End-Header%
  */

  /*
   * Force inclusion of SVID stuff since we need it if we're compiling in
   * gcc-wall wall mode
   * But not deprecated in glibc >= 20, and not needed nowadays.
   */
   /* #define _SVID_SOURCE */

 #include "config.h"
 #if defined(_MSC_VER)
 #include <BaseTsd.h>
 typedef SSIZE_T ssize_t;
 #endif
 #ifdef WIN32
 #define WIN32_WINNT 0x0500
 #include <io.h>
 typedef int mode_t;
 #include <windows.h>
 #define UUID MYUUID
 #endif
 #include <stdio.h>
 #ifdef HAVE_UNISTD_H
 #include <unistd.h>
 #endif
 #ifdef HAVE_STDLIB_H
 #include <stdlib.h>
 #endif
 #include <string.h>
 #include <fcntl.h>
 #include <errno.h>
 #include <limits.h>
 #include <sys/types.h>
 #ifdef HAVE_SYS_TIME_H
 #include <sys/time.h>
 #endif
 #include <sys/stat.h>
 #ifdef HAVE_SYS_FILE_H
 #include <sys/file.h>
 #endif
 #ifdef HAVE_SYS_IOCTL_H
 #include <sys/ioctl.h>
 #endif
 #ifdef HAVE_SYS_SOCKET_H
 #include <sys/socket.h>
 #endif
 #ifdef HAVE_SYS_UN_H
 #include <sys/un.h>
 #endif
 #ifdef HAVE_SYS_SOCKIO_H
 #include <sys/sockio.h>
 #endif
 #ifdef HAVE_NET_IF_H
 #include <net/if.h>
 #endif
 #ifdef HAVE_NETINET_IN_H
 #include <netinet/in.h>
 #endif
 #ifdef HAVE_NET_IF_DL_H
 #include <net/if_dl.h>
 #endif
 #if defined(__linux__) && defined(HAVE_SYS_SYSCALL_H)
 #include <sys/syscall.h>
 #endif

 #include "uuidP.h"
 #include "uuidd.h"

 #ifdef HAVE_TLS
 #define THREAD_LOCAL static __thread
 #else
 #define THREAD_LOCAL static
 #endif

 #ifdef WIN32
 static void gettimeofday(struct st_tm_val *tv, void *dummy)
 {
 	FILETIME	ftime;
 	uint64_t	n;

 	GetSystemTimeAsFileTime(&ftime);
 	n = (((uint64_t)ftime.dwHighDateTime << 32)
 		+ (uint64_t)ftime.dwLowDateTime);
 	if (n) {
 		n /= 10;
 		n -= ((369 * 365 + 89) * (uint64_t)86400) * 1000000;
 	}

 	tv->tv_sec = n / 1000000;
 	tv->tv_usec = n % 1000000;
 }

 static int getuid(void)
 {
 	return 1;
 }
 #endif

 /*
  * Get the ethernet hardware address, if we can find it...
  *
  * XXX for a windows version, probably should use GetAdaptersInfo:
  * http://www.codeguru.com/cpp/i-n/network/networkinformation/article.php/c5451
  * commenting out get_node_id just to get gen_uuid to compile under windows
  * is not the right way to go!
  */
 static int get_node_id(unsigned char *node_id)
 {
 #ifdef HAVE_NET_IF_H
 	int		sd;
 	struct ifreq	ifr, *ifrp;
 	struct ifconf	ifc;
 	char buf[1024];
 	int		n, i;
 	unsigned char	*a;
 #ifdef HAVE_NET_IF_DL_H
 	struct sockaddr_dl *sdlp;
 #endif

 	/*
 	 * BSD 4.4 defines the size of an ifreq to be
 	 * max(sizeof(ifreq), sizeof(ifreq.ifr_name)+ifreq.ifr_addr.sa_len
 	 * However, under earlier systems, sa_len isn't present, so the size is
 	 * just sizeof(struct ifreq)
 	 */
 #ifdef HAVE_SA_LEN
 #define max(x, y) (((x) > (y)) ? (x) : (y))
 #define ifreq_size(i) max(sizeof(struct ifreq),\
      sizeof((i).ifr_name)+(i).ifr_addr.sa_len)
 #else
 #define ifreq_size(i) sizeof(struct ifreq)
 #endif /* HAVE_SA_LEN */

 	sd = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);
 	if (sd < 0) {
 		return -1;
 	}
 	memset(buf, 0, sizeof(buf));
 	ifc.ifc_len = sizeof(buf);
 	ifc.ifc_buf = buf;
 	if (ioctl(sd, SIOCGIFCONF, (char *)&ifc) < 0) {
 		close(sd);
 		return -1;
 	}
 	n = ifc.ifc_len;
 	for (i = 0; i < n; i += ifreq_size(*ifrp)) {
 		ifrp = (struct ifreq *)((char *)ifc.ifc_buf + i);
 		strncpy(ifr.ifr_name, ifrp->ifr_name, IFNAMSIZ);
 #ifdef SIOCGIFHWADDR
 		if (ioctl(sd, SIOCGIFHWADDR, &ifr) < 0)
 			continue;
 		a = (unsigned char *)&ifr.ifr_hwaddr.sa_data;
 #else
 #ifdef SIOCGENADDR
 		if (ioctl(sd, SIOCGENADDR, &ifr) < 0)
 			continue;
 		a = (unsigned char *)ifr.ifr_enaddr;
 #else
 #ifdef HAVE_NET_IF_DL_H
 		sdlp = (struct sockaddr_dl *) &ifrp->ifr_addr;
 		if ((sdlp->sdl_family != AF_LINK) || (sdlp->sdl_alen != 6))
 			continue;
 		a = (unsigned char *)&sdlp->sdl_data[sdlp->sdl_nlen];
 #else
 		/*
 		 * XXX we don't have a way of getting the hardware
 		 * address
 		 */
 		close(sd);
 		return 0;
 #endif /* HAVE_NET_IF_DL_H */
 #endif /* SIOCGENADDR */
 #endif /* SIOCGIFHWADDR */
 		if (!a[0] && !a[1] && !a[2] && !a[3] && !a[4] && !a[5])
 			continue;
 		if (node_id) {
 			memcpy(node_id, a, 6);
 			close(sd);
 			return 1;
 		}
 	}
 	close(sd);
 #endif
 	return 0;
 }

 #if defined(__linux__) && defined(__NR_gettid) && defined(HAVE_JRAND48)
 #define DO_JRAND_MIX
 static unsigned short ul_jrand_seed[3];
 #endif

 static int random_get_fd(void)
 {
 	int i, fd = -1;
 	struct st_tm_val  tv;

 	gettimeofday(&tv, 0);
 #ifndef WIN32
 	fd = open("/dev/urandom", O_RDONLY);
 	if (fd == -1)
 		fd = open("/dev/random", O_RDONLY | O_NONBLOCK);
 	if (fd >= 0) {
 		i = fcntl(fd, F_GETFD);
 		if (i >= 0)
 			fcntl(fd, F_SETFD, i | FD_CLOEXEC);
 	}
 #endif
 	srand((getpid() << 16) ^ getuid() ^ tv.tv_sec ^ tv.tv_usec);

 #ifdef DO_JRAND_MIX
 	ul_jrand_seed[0] = getpid() ^ (tv.tv_sec & 0xFFFF);
 	ul_jrand_seed[1] = getppid() ^ (tv.tv_usec & 0xFFFF);
 	ul_jrand_seed[2] = (tv.tv_sec ^ tv.tv_usec) >> 16;
 #endif
 	/* Crank the random number generator a few times */
 	gettimeofday(&tv, 0);
 	for (i = (tv.tv_sec ^ tv.tv_usec) & 0x1F; i > 0; i--)
 		rand();
 	return fd;
 }

 /*
  * Generate a stream of random nbytes into buf.
  * Use /dev/urandom if possible, and if not,
  * use glibc pseudo-random functions.
  */
 static void random_get_bytes(void *buf, size_t nbytes)
 {
 	size_t i, n = nbytes;
 	int fd = random_get_fd();
 	int lose_counter = 0;
 	unsigned char *cp = (unsigned char *)buf;

 	if (fd >= 0) {
 		while (n > 0) {
 			ssize_t x = read(fd, cp, n);
 			if (x <= 0) {
 				if (lose_counter++ > 16)
 					break;
 				continue;
 			}
 			n -= x;
 			cp += x;
 			lose_counter = 0;
 		}

 		close(fd);
 	}

 	/*
 	 * We do this all the time, but this is the only source of
 	 * randomness if /dev/random/urandom is out to lunch.
 	 */
 	for (cp = buf, i = 0; i < nbytes; i++)
 		*cp++ ^= (rand() >> 7) & 0xFF;

 #ifdef DO_JRAND_MIX
 	{
 		unsigned short tmp_seed[3];

 		memcpy(tmp_seed, ul_jrand_seed, sizeof(tmp_seed));
 		ul_jrand_seed[2] = ul_jrand_seed[2] ^ syscall(__NR_gettid);
 		for (cp = buf, i = 0; i < nbytes; i++)
 			*cp++ ^= (jrand48(tmp_seed) >> 7) & 0xFF;
 		memcpy(ul_jrand_seed, tmp_seed,
 			sizeof(ul_jrand_seed) - sizeof(unsigned short));
 	}
 #endif

 	return;
 }

 #ifdef WIN32 /* compatibility layer */
 #define LOCK_EX 1
 #define LOCK_UN 2
 static int flock(int fd, int op)
 {
 	HANDLE h = (HANDLE)_get_osfhandle(fd);
 	OVERLAPPED offset;
 	if (h < 0)
 		return -1;
 	memset(&offset, 0, sizeof(offset));
 	switch (op) {
 	case LOCK_EX:
 		return (LockFileEx(h, LOCKFILE_EXCLUSIVE_LOCK, 0, 1, 0, &offset)) ? 0 : -1;
 	case LOCK_UN:
 		UnlockFileEx(h, 0, 1, 0, &offset);
 		return 0;
 	}
 	return -1;
 }
 #endif

 /* Assume that the gettimeofday() has microsecond granularity */
 #define MAX_ADJUSTMENT 10

 static int get_random_fd(void)
 {
 	struct st_tm_val  tv;
 	static int  fd = -2;
 	int    i;
 #ifndef WIN32
 	if (fd == -2) {
 		gettimeofday(&tv, 0);
 		fd = open("/dev/urandom", O_RDONLY);
 		if (fd == -1)
 			fd = open("/dev/random", O_RDONLY | O_NONBLOCK);
 		srand((getpid() << 16) ^ getuid() ^ tv.tv_sec ^ tv.tv_usec);
 	}
 	/* Crank the random number generator a few times */
 	gettimeofday(&tv, 0);
 	for (i = (tv.tv_sec ^ tv.tv_usec) & 0x1F; i > 0; i--)
 		rand();
 #endif
 	return fd;
 }

 /*
  * Generate a series of random bytes.  Use /dev/urandom if possible,
  * and if not, use srandom/random.
  */
 static void get_random_bytes(void *buf, int nbytes)
 {
 	int i, n = nbytes, fd = get_random_fd();
 	int lose_counter = 0;
 	unsigned char *cp = (unsigned char *)buf;

 	if (fd >= 0) {
 		while (n > 0) {
 			i = read(fd, cp, n);
 			if (i <= 0) {
 				if (lose_counter++ > 16)
 					break;
 				continue;
 			}
 			n -= i;
 			cp += i;
 			lose_counter = 0;
 		}
 	}

 	/*
 	 * We do this all the time, but this is the only source of
 	 * randomness if /dev/random/urandom is out to lunch.
 	 */
 	for (cp = buf, i = 0; i < nbytes; i++)
 		*cp++ ^= (rand() >> 7) & 0xFF;
 }


 /*
  * Get clock from global sequence clock counter.
  *
  * Return -1 if the clock counter could not be opened/locked (in this case
  * pseudorandom value is returned in @ret_clock_seq), otherwise return 0.
  */
  /**/
 static int get_clock(uint32_t *clock_high, uint32_t *clock_low,
   uint16_t *ret_clock_seq, int *num)
 #ifdef WIN32
 {
 	static int      adjustment = 0;
 	static struct st_tm_val    last = { 0, 0 };
 	static uint16_t      clock_seq;
 	struct st_tm_val      tv;
 	uint64_t    clock_reg;

 try_again:
 	gettimeofday(&tv, 0);
 	if ((last.tv_sec == 0) && (last.tv_usec == 0)) {
 		get_random_bytes(&clock_seq, sizeof(clock_seq));
 		clock_seq &= 0x3FFF;
 		last = tv;
 		last.tv_sec--;
 	}
 	if ((tv.tv_sec < last.tv_sec) ||
 		((tv.tv_sec == last.tv_sec) &&
 		(tv.tv_usec < last.tv_usec))) {
 		clock_seq = (clock_seq + 1) & 0x3FFF;
 		adjustment = 0;
 		last = tv;
 	}
 	else if ((tv.tv_sec == last.tv_sec) &&
 		(tv.tv_usec == last.tv_usec)) {
 		if (adjustment >= MAX_ADJUSTMENT)
 			goto try_again;
 		adjustment++;
 	}
 	else {
 		adjustment = 0;
 		last = tv;
 	}

 	clock_reg = tv.tv_usec * 10 + adjustment;
 	clock_reg += ((uint64_t)tv.tv_sec) * 10000000;
 	clock_reg += (((uint64_t)0x01B21DD2) << 32) + 0x13814000;

 	*clock_high = clock_reg >> 32;
 	*clock_low = clock_reg;
 	*ret_clock_seq = clock_seq;
 	return 0;
 }
 #else
 {
 	THREAD_LOCAL int		adjustment = 0;
 	THREAD_LOCAL struct st_tm_val	last = { 0, 0 };
 	THREAD_LOCAL int		state_fd = -2;
 	THREAD_LOCAL FILE		*state_f;
 	THREAD_LOCAL uint16_t		clock_seq;
 	struct st_tm_val			tv;
 	uint64_t			clock_reg;
 	mode_t				save_umask;
 	int				len;
 	int				ret = 0;

 	if (state_fd == -2) {
 		save_umask = umask(0);
 		state_fd = open(LIBUUID_CLOCK_FILE, O_RDWR | O_CREAT, 0660);
 		(void)umask(save_umask);
 		if (state_fd != -1) {
 			state_f = fdopen(state_fd, "r+");
 			if (!state_f) {
 				close(state_fd);
 				state_fd = -1;
 				ret = -1;
 			}
 		}
 		else
 			ret = -1;
 	}
 	if (state_fd >= 0) {
 		rewind(state_f);
 #ifdef HAVE_FLOCK
 		while (flock(state_fd, LOCK_EX) < 0) {
 			if ((errno == EAGAIN) || (errno == EINTR))
 				continue;
 			fclose(state_f);
 			close(state_fd);
 			state_fd = -1;
 			ret = -1;
 			break;
 		}
 #endif
 	}
 	if (state_fd >= 0) {
 		unsigned int cl;
 		unsigned long tv1, tv2;
 		int a;

 		if (fscanf(state_f, "clock: %04x tv: %lu %lu adj: %d\n",
 			&cl, &tv1, &tv2, &a) == 4) {
 			clock_seq = cl & 0x3FFF;
 			last.tv_sec = tv1;
 			last.tv_usec = tv2;
 			adjustment = a;
 		}
 	}

 	if ((last.tv_sec == 0) && (last.tv_usec == 0)) {
 		random_get_bytes(&clock_seq, sizeof(clock_seq));
 		clock_seq &= 0x3FFF;
 		gettimeofday(&last, 0);
 		last.tv_sec--;
 	}

 try_again:
 	gettimeofday(&tv, 0);
 	if ((tv.tv_sec < last.tv_sec) ||
 		((tv.tv_sec == last.tv_sec) &&
 		(tv.tv_usec < last.tv_usec))) {
 		clock_seq = (clock_seq + 1) & 0x3FFF;
 		adjustment = 0;
 		last = tv;
 	}
 	else if ((tv.tv_sec == last.tv_sec) &&
 		(tv.tv_usec == last.tv_usec)) {
 		if (adjustment >= MAX_ADJUSTMENT)
 			goto try_again;
 		adjustment++;
 	}
 	else {
 		adjustment = 0;
 		last = tv;
 	}

 	clock_reg = tv.tv_usec * 10 + adjustment;
 	clock_reg += ((uint64_t)tv.tv_sec) * 10000000;
 	clock_reg += (((uint64_t)0x01B21DD2) << 32) + 0x13814000;

 	if (num && (*num > 1)) {
 		adjustment += *num - 1;
 		last.tv_usec += adjustment / 10;
 		adjustment = adjustment % 10;
 		last.tv_sec += last.tv_usec / 1000000;
 		last.tv_usec = last.tv_usec % 1000000;
 	}

 	if (state_fd >= 0) {
 		rewind(state_f);
 		len = fprintf(state_f,
 			"clock: %04x tv: %016lu %08lu adj: %08d\n",
 			clock_seq, (unsigned long)last.tv_sec, (unsigned long)last.tv_usec, adjustment);
 		fflush(state_f);
 		if (ftruncate(state_fd, len) < 0) {
 			fprintf(state_f, "                   \n");
 			fflush(state_f);
 		}
 		rewind(state_f);
 #ifdef HAVE_FLOCK
 		flock(state_fd, LOCK_UN);
 #endif
 	}

 	*clock_high = clock_reg >> 32;
 	*clock_low = clock_reg;
 	*ret_clock_seq = clock_seq;
 	return ret;
 }
 #endif


 int __uuid_generate_time(UUID_FIELD out, int *num)
 {
 	static unsigned char node_id[6];
 	static int has_init = 0;
 	struct uuid uu;
 	uint32_t	clock_mid;
 	int ret;

 	if (!has_init) {
 		if (get_node_id(node_id) <= 0) {
 			random_get_bytes(node_id, 6);
 			/*
 			 * Set multicast bit, to prevent conflicts
 			 * with IEEE 802 addresses obtained from
 			 * network cards
 			 */
 			node_id[0] |= 0x01;
 		}
 		has_init = 1;
 	}
 	ret = get_clock(&clock_mid, &uu.time_low, &uu.clock_seq, num);
 	uu.clock_seq |= 0x8000;
 	uu.time_mid = (uint16_t)clock_mid;
 	uu.time_hi_and_version = ((clock_mid >> 16) & 0x0FFF) | 0x1000;
 	memcpy(uu.node, node_id, 6);
 	uuid_pack(&uu, out);
 	return ret;
 }

 /*
  * Generate time-based UUID and store it to @out
  *
  * Since there is no daemon here, use fall-back right away
  */
 static int uuid_generate_time_generic(UUID_FIELD out) {
 	return __uuid_generate_time(out, 0);
 }

 /*
  * Generate time-based UUID and store it to @out.
  *
  * Discards return value from uuid_generate_time_generic()
  */
 void uuid_generate_time(UUID_FIELD out)
 {
 	(void)uuid_generate_time_generic(out);
 }


 int uuid_generate_time_safe(UUID_FIELD out)
 {
 	return uuid_generate_time_generic(out);
 }


 void __uuid_generate_random(UUID_FIELD out, int *num)
 {
 	UUID_FIELD	buf;
 	struct uuid uu;
 	int i, n;

 	if (!num || !*num)
 		n = 1;
 	else
 		n = *num;

 	for (i = 0; i < n; i++) {
 		random_get_bytes(buf, sizeof(buf));
 		uuid_unpack(buf, &uu);

 		uu.clock_seq = (uu.clock_seq & 0x3FFF) | 0x8000;
 		uu.time_hi_and_version = (uu.time_hi_and_version & 0x0FFF)
 			| 0x4000;
 		uuid_pack(&uu, out);
 		out += sizeof(UUID_FIELD);
 	}
 }

 void uuid_generate_random(UUID_FIELD out)
 {
 	int	num = 1;
 	/* No real reason to use the daemon for random uuid's -- yet */

 	__uuid_generate_random(out, &num);
 }

 /*
  * Check whether good random source (/dev/random or /dev/urandom)
  * is available.
  */
 static int have_random_source(void)
 {
 	struct stat s;

 	return (!stat("/dev/random", &s) || !stat("/dev/urandom", &s));
 }


 /*
  * This is the generic front-end to uuid_generate_random and
  * uuid_generate_time.  It uses uuid_generate_random only if
  * /dev/urandom is available, since otherwise we won't have
  * high-quality randomness.
  */
 void uuid_generate(UUID_FIELD out)
 {
 	if (have_random_source())
 		uuid_generate_random(out);
 	else
 		uuid_generate_time(out);
 }
	/*
	* gen_uuid.c --- generate a DCE-compatible uuid
	*
	* Copyright (C) 1996, 1997, 1998, 1999 Theodore Ts'o.
	*
	* %Begin-Header%
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	* 1. Redistributions of source code must retain the above copyright
	* notice, and the entire permission notice in its entirety,
	* including the disclaimer of warranties.
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	* 3. The name of the author may not be used to endorse or promote
	* products derived from this software without specific prior
	* written permission.
	*
	* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ALL OF
	* WHICH ARE HEREBY DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE
	* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
	* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
	* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
	* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
	* USE OF THIS SOFTWARE, EVEN IF NOT ADVISED OF THE POSSIBILITY OF SUCH
	* DAMAGE.
	* %End-Header%
	*/

	/*
	* Force inclusion of SVID stuff since we need it if we're compiling in
	* gcc-wall wall mode
	* But not deprecated in glibc >= 20, and not needed nowadays.
	*/
	/* #define _SVID_SOURCE */

	#include "config.h"
	#if defined(_MSC_VER)
	#include <BaseTsd.h>
	typedef SSIZE_T ssize_t;
	#endif
	#ifdef WIN32
	#define WIN32_WINNT 0x0500
	#include <io.h>
	typedef int mode_t;
	#include <windows.h>
	#define UUID MYUUID
	#endif
	#include <stdio.h>
	#ifdef HAVE_UNISTD_H
	#include <unistd.h>
	#endif
	#ifdef HAVE_STDLIB_H
	#include <stdlib.h>
	#endif
	#include <string.h>
	#include <fcntl.h>
	#include <errno.h>
	#include <limits.h>
	#include <sys/types.h>
	#ifdef HAVE_SYS_TIME_H
	#include <sys/time.h>
	#endif
	#include <sys/stat.h>
	#ifdef HAVE_SYS_FILE_H
	#include <sys/file.h>
	#endif
	#ifdef HAVE_SYS_IOCTL_H
	#include <sys/ioctl.h>
	#endif
	#ifdef HAVE_SYS_SOCKET_H
	#include <sys/socket.h>
	#endif
	#ifdef HAVE_SYS_UN_H
	#include <sys/un.h>
	#endif
	#ifdef HAVE_SYS_SOCKIO_H
	#include <sys/sockio.h>
	#endif
	#ifdef HAVE_NET_IF_H
	#include <net/if.h>
	#endif
	#ifdef HAVE_NETINET_IN_H
	#include <netinet/in.h>
	#endif
	#ifdef HAVE_NET_IF_DL_H
	#include <net/if_dl.h>
	#endif
	#if defined(__linux__) && defined(HAVE_SYS_SYSCALL_H)
	#include <sys/syscall.h>
	#endif

	#include "uuidP.h"
	#include "uuidd.h"

	#ifdef HAVE_TLS
	#define THREAD_LOCAL static __thread
	#else
	#define THREAD_LOCAL static
	#endif

	#ifdef WIN32
	static void gettimeofday(struct st_tm_val tv, void dummy)
	{
	FILETIME ftime;
	uint64_t n;

	GetSystemTimeAsFileTime(&ftime);
	n = (((uint64_t)ftime.dwHighDateTime << 32)
	+ (uint64_t)ftime.dwLowDateTime);
	if (n) {
	n /= 10;
	n -= ((369 * 365 + 89) * (uint64_t)86400) * 1000000;
	}

	tv->tv_sec = n / 1000000;
	tv->tv_usec = n % 1000000;
	}

	static int getuid(void)
	{
	return 1;
	}
	#endif

	/*
	* Get the ethernet hardware address, if we can find it...
	*
	* XXX for a windows version, probably should use GetAdaptersInfo:
	* http://www.codeguru.com/cpp/i-n/network/networkinformation/article.php/c5451
	* commenting out get_node_id just to get gen_uuid to compile under windows
	* is not the right way to go!
	*/
	static int get_node_id(unsigned char *node_id)
	{
	#ifdef HAVE_NET_IF_H
	int sd;
	struct ifreq ifr, *ifrp;
	struct ifconf ifc;
	char buf[1024];
	int n, i;
	unsigned char *a;
	#ifdef HAVE_NET_IF_DL_H
	struct sockaddr_dl *sdlp;
	#endif

	/*
	* BSD 4.4 defines the size of an ifreq to be
	* max(sizeof(ifreq), sizeof(ifreq.ifr_name)+ifreq.ifr_addr.sa_len
	* However, under earlier systems, sa_len isn't present, so the size is
	* just sizeof(struct ifreq)
	*/
	#ifdef HAVE_SA_LEN
	#define max(x, y) (((x) > (y)) ? (x) : (y))
	#define ifreq_size(i) max(sizeof(struct ifreq),\
	sizeof((i).ifr_name)+(i).ifr_addr.sa_len)
	#else
	#define ifreq_size(i) sizeof(struct ifreq)
	#endif /* HAVE_SA_LEN */

	sd = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);
	if (sd < 0) {
	return -1;
	}
	memset(buf, 0, sizeof(buf));
	ifc.ifc_len = sizeof(buf);
	ifc.ifc_buf = buf;
	if (ioctl(sd, SIOCGIFCONF, (char *)&ifc) < 0) {
	close(sd);
	return -1;
	}
	n = ifc.ifc_len;
	for (i = 0; i < n; i += ifreq_size(*ifrp)) {
	ifrp = (struct ifreq )((char )ifc.ifc_buf + i);
	strncpy(ifr.ifr_name, ifrp->ifr_name, IFNAMSIZ);
	#ifdef SIOCGIFHWADDR
	if (ioctl(sd, SIOCGIFHWADDR, &ifr) < 0)
	continue;
	a = (unsigned char *)&ifr.ifr_hwaddr.sa_data;
	#else
	#ifdef SIOCGENADDR
	if (ioctl(sd, SIOCGENADDR, &ifr) < 0)
	continue;
	a = (unsigned char *)ifr.ifr_enaddr;
	#else
	#ifdef HAVE_NET_IF_DL_H
	sdlp = (struct sockaddr_dl *) &ifrp->ifr_addr;
	if ((sdlp->sdl_family != AF_LINK) \|\| (sdlp->sdl_alen != 6))
	continue;
	a = (unsigned char *)&sdlp->sdl_data[sdlp->sdl_nlen];
	#else
	/*
	* XXX we don't have a way of getting the hardware
	* address
	*/
	close(sd);
	return 0;
	#endif /* HAVE_NET_IF_DL_H */
	#endif /* SIOCGENADDR */
	#endif /* SIOCGIFHWADDR */
	if (!a[0] && !a[1] && !a[2] && !a[3] && !a[4] && !a[5])
	continue;
	if (node_id) {
	memcpy(node_id, a, 6);
	close(sd);
	return 1;
	}
	}
	close(sd);
	#endif
	return 0;
	}

	#if defined(__linux__) && defined(__NR_gettid) && defined(HAVE_JRAND48)
	#define DO_JRAND_MIX
	static unsigned short ul_jrand_seed[3];
	#endif

	static int random_get_fd(void)
	{
	int i, fd = -1;
	struct st_tm_val tv;

	gettimeofday(&tv, 0);
	#ifndef WIN32
	fd = open("/dev/urandom", O_RDONLY);
	if (fd == -1)
	fd = open("/dev/random", O_RDONLY \| O_NONBLOCK);
	if (fd >= 0) {
	i = fcntl(fd, F_GETFD);
	if (i >= 0)
	fcntl(fd, F_SETFD, i \| FD_CLOEXEC);
	}
	#endif
	srand((getpid() << 16) ^ getuid() ^ tv.tv_sec ^ tv.tv_usec);

	#ifdef DO_JRAND_MIX
	ul_jrand_seed[0] = getpid() ^ (tv.tv_sec & 0xFFFF);
	ul_jrand_seed[1] = getppid() ^ (tv.tv_usec & 0xFFFF);
	ul_jrand_seed[2] = (tv.tv_sec ^ tv.tv_usec) >> 16;
	#endif
	/* Crank the random number generator a few times */
	gettimeofday(&tv, 0);
	for (i = (tv.tv_sec ^ tv.tv_usec) & 0x1F; i > 0; i--)
	rand();
	return fd;
	}

	/*
	* Generate a stream of random nbytes into buf.
	* Use /dev/urandom if possible, and if not,
	* use glibc pseudo-random functions.
	*/
	static void random_get_bytes(void *buf, size_t nbytes)
	{
	size_t i, n = nbytes;
	int fd = random_get_fd();
	int lose_counter = 0;
	unsigned char cp = (unsigned char )buf;

	if (fd >= 0) {
	while (n > 0) {
	ssize_t x = read(fd, cp, n);
	if (x <= 0) {
	if (lose_counter++ > 16)
	break;
	continue;
	}
	n -= x;
	cp += x;
	lose_counter = 0;
	}

	close(fd);
	}

	/*
	* We do this all the time, but this is the only source of
	* randomness if /dev/random/urandom is out to lunch.
	*/
	for (cp = buf, i = 0; i < nbytes; i++)
	*cp++ ^= (rand() >> 7) & 0xFF;

	#ifdef DO_JRAND_MIX
	{
	unsigned short tmp_seed[3];

	memcpy(tmp_seed, ul_jrand_seed, sizeof(tmp_seed));
	ul_jrand_seed[2] = ul_jrand_seed[2] ^ syscall(__NR_gettid);
	for (cp = buf, i = 0; i < nbytes; i++)
	*cp++ ^= (jrand48(tmp_seed) >> 7) & 0xFF;
	memcpy(ul_jrand_seed, tmp_seed,
	sizeof(ul_jrand_seed) - sizeof(unsigned short));
	}
	#endif

	return;
	}

	#ifdef WIN32 /* compatibility layer */
	#define LOCK_EX 1
	#define LOCK_UN 2
	static int flock(int fd, int op)
	{
	HANDLE h = (HANDLE)_get_osfhandle(fd);
	OVERLAPPED offset;
	if (h < 0)
	return -1;
	memset(&offset, 0, sizeof(offset));
	switch (op) {
	case LOCK_EX:
	return (LockFileEx(h, LOCKFILE_EXCLUSIVE_LOCK, 0, 1, 0, &offset)) ? 0 : -1;
	case LOCK_UN:
	UnlockFileEx(h, 0, 1, 0, &offset);
	return 0;
	}
	return -1;
	}
	#endif

	/* Assume that the gettimeofday() has microsecond granularity */
	#define MAX_ADJUSTMENT 10

	static int get_random_fd(void)
	{
	struct st_tm_val tv;
	static int fd = -2;
	int i;
	#ifndef WIN32
	if (fd == -2) {
	gettimeofday(&tv, 0);
	fd = open("/dev/urandom", O_RDONLY);
	if (fd == -1)
	fd = open("/dev/random", O_RDONLY \| O_NONBLOCK);
	srand((getpid() << 16) ^ getuid() ^ tv.tv_sec ^ tv.tv_usec);
	}
	/* Crank the random number generator a few times */
	gettimeofday(&tv, 0);
	for (i = (tv.tv_sec ^ tv.tv_usec) & 0x1F; i > 0; i--)
	rand();
	#endif
	return fd;
	}

	/*
	* Generate a series of random bytes. Use /dev/urandom if possible,
	* and if not, use srandom/random.
	*/
	static void get_random_bytes(void *buf, int nbytes)
	{
	int i, n = nbytes, fd = get_random_fd();
	int lose_counter = 0;
	unsigned char cp = (unsigned char )buf;

	if (fd >= 0) {
	while (n > 0) {
	i = read(fd, cp, n);
	if (i <= 0) {
	if (lose_counter++ > 16)
	break;
	continue;
	}
	n -= i;
	cp += i;
	lose_counter = 0;
	}
	}

	/*
	* We do this all the time, but this is the only source of
	* randomness if /dev/random/urandom is out to lunch.
	*/
	for (cp = buf, i = 0; i < nbytes; i++)
	*cp++ ^= (rand() >> 7) & 0xFF;
	}


	/*
	* Get clock from global sequence clock counter.
	*
	* Return -1 if the clock counter could not be opened/locked (in this case
	* pseudorandom value is returned in @ret_clock_seq), otherwise return 0.
	*/
	/**/
	static int get_clock(uint32_t clock_high, uint32_t clock_low,
	uint16_t ret_clock_seq, int num)
	#ifdef WIN32
	{
	static int adjustment = 0;
	static struct st_tm_val last = { 0, 0 };
	static uint16_t clock_seq;
	struct st_tm_val tv;
	uint64_t clock_reg;

	try_again:
	gettimeofday(&tv, 0);
	if ((last.tv_sec == 0) && (last.tv_usec == 0)) {
	get_random_bytes(&clock_seq, sizeof(clock_seq));
	clock_seq &= 0x3FFF;
	last = tv;
	last.tv_sec--;
	}
	if ((tv.tv_sec < last.tv_sec) \|\|
	((tv.tv_sec == last.tv_sec) &&
	(tv.tv_usec < last.tv_usec))) {
	clock_seq = (clock_seq + 1) & 0x3FFF;
	adjustment = 0;
	last = tv;
	}
	else if ((tv.tv_sec == last.tv_sec) &&
	(tv.tv_usec == last.tv_usec)) {
	if (adjustment >= MAX_ADJUSTMENT)
	goto try_again;
	adjustment++;
	}
	else {
	adjustment = 0;
	last = tv;
	}

	clock_reg = tv.tv_usec * 10 + adjustment;
	clock_reg += ((uint64_t)tv.tv_sec) * 10000000;
	clock_reg += (((uint64_t)0x01B21DD2) << 32) + 0x13814000;

	*clock_high = clock_reg >> 32;
	*clock_low = clock_reg;
	*ret_clock_seq = clock_seq;
	return 0;
	}
	#else
	{
	THREAD_LOCAL int adjustment = 0;
	THREAD_LOCAL struct st_tm_val last = { 0, 0 };
	THREAD_LOCAL int state_fd = -2;
	THREAD_LOCAL FILE *state_f;
	THREAD_LOCAL uint16_t clock_seq;
	struct st_tm_val tv;
	uint64_t clock_reg;
	mode_t save_umask;
	int len;
	int ret = 0;

	if (state_fd == -2) {
	save_umask = umask(0);
	state_fd = open(LIBUUID_CLOCK_FILE, O_RDWR \| O_CREAT, 0660);
	(void)umask(save_umask);
	if (state_fd != -1) {
	state_f = fdopen(state_fd, "r+");
	if (!state_f) {
	close(state_fd);
	state_fd = -1;
	ret = -1;
	}
	}
	else
	ret = -1;
	}
	if (state_fd >= 0) {
	rewind(state_f);
	#ifdef HAVE_FLOCK
	while (flock(state_fd, LOCK_EX) < 0) {
	if ((errno == EAGAIN) \|\| (errno == EINTR))
	continue;
	fclose(state_f);
	close(state_fd);
	state_fd = -1;
	ret = -1;
	break;
	}
	#endif
	}
	if (state_fd >= 0) {
	unsigned int cl;
	unsigned long tv1, tv2;
	int a;

	if (fscanf(state_f, "clock: %04x tv: %lu %lu adj: %d\n",
	&cl, &tv1, &tv2, &a) == 4) {
	clock_seq = cl & 0x3FFF;
	last.tv_sec = tv1;
	last.tv_usec = tv2;
	adjustment = a;
	}
	}

	if ((last.tv_sec == 0) && (last.tv_usec == 0)) {
	random_get_bytes(&clock_seq, sizeof(clock_seq));
	clock_seq &= 0x3FFF;
	gettimeofday(&last, 0);
	last.tv_sec--;
	}

	try_again:
	gettimeofday(&tv, 0);
	if ((tv.tv_sec < last.tv_sec) \|\|
	((tv.tv_sec == last.tv_sec) &&
	(tv.tv_usec < last.tv_usec))) {
	clock_seq = (clock_seq + 1) & 0x3FFF;
	adjustment = 0;
	last = tv;
	}
	else if ((tv.tv_sec == last.tv_sec) &&
	(tv.tv_usec == last.tv_usec)) {
	if (adjustment >= MAX_ADJUSTMENT)
	goto try_again;
	adjustment++;
	}
	else {
	adjustment = 0;
	last = tv;
	}

	clock_reg = tv.tv_usec * 10 + adjustment;
	clock_reg += ((uint64_t)tv.tv_sec) * 10000000;
	clock_reg += (((uint64_t)0x01B21DD2) << 32) + 0x13814000;

	if (num && (*num > 1)) {
	adjustment += *num - 1;
	last.tv_usec += adjustment / 10;
	adjustment = adjustment % 10;
	last.tv_sec += last.tv_usec / 1000000;
	last.tv_usec = last.tv_usec % 1000000;
	}

	if (state_fd >= 0) {
	rewind(state_f);
	len = fprintf(state_f,
	"clock: %04x tv: %016lu %08lu adj: %08d\n",
	clock_seq, (unsigned long)last.tv_sec, (unsigned long)last.tv_usec, adjustment);
	fflush(state_f);
	if (ftruncate(state_fd, len) < 0) {
	fprintf(state_f, " \n");
	fflush(state_f);
	}
	rewind(state_f);
	#ifdef HAVE_FLOCK
	flock(state_fd, LOCK_UN);
	#endif
	}

	*clock_high = clock_reg >> 32;
	*clock_low = clock_reg;
	*ret_clock_seq = clock_seq;
	return ret;
	}
	#endif


	int __uuid_generate_time(UUID_FIELD out, int *num)
	{
	static unsigned char node_id[6];
	static int has_init = 0;
	struct uuid uu;
	uint32_t clock_mid;
	int ret;

	if (!has_init) {
	if (get_node_id(node_id) <= 0) {
	random_get_bytes(node_id, 6);
	/*
	* Set multicast bit, to prevent conflicts
	* with IEEE 802 addresses obtained from
	* network cards
	*/
	node_id[0] \|= 0x01;
	}
	has_init = 1;
	}
	ret = get_clock(&clock_mid, &uu.time_low, &uu.clock_seq, num);
	uu.clock_seq \|= 0x8000;
	uu.time_mid = (uint16_t)clock_mid;
	uu.time_hi_and_version = ((clock_mid >> 16) & 0x0FFF) \| 0x1000;
	memcpy(uu.node, node_id, 6);
	uuid_pack(&uu, out);
	return ret;
	}

	/*
	* Generate time-based UUID and store it to @out
	*
	* Since there is no daemon here, use fall-back right away
	*/
	static int uuid_generate_time_generic(UUID_FIELD out) {
	return __uuid_generate_time(out, 0);
	}

	/*
	* Generate time-based UUID and store it to @out.
	*
	* Discards return value from uuid_generate_time_generic()
	*/
	void uuid_generate_time(UUID_FIELD out)
	{
	(void)uuid_generate_time_generic(out);
	}


	int uuid_generate_time_safe(UUID_FIELD out)
	{
	return uuid_generate_time_generic(out);
	}


	void __uuid_generate_random(UUID_FIELD out, int *num)
	{
	UUID_FIELD buf;
	struct uuid uu;
	int i, n;

	if (!num \|\| !*num)
	n = 1;
	else
	n = *num;

	for (i = 0; i < n; i++) {
	random_get_bytes(buf, sizeof(buf));
	uuid_unpack(buf, &uu);

	uu.clock_seq = (uu.clock_seq & 0x3FFF) \| 0x8000;
	uu.time_hi_and_version = (uu.time_hi_and_version & 0x0FFF)
	\| 0x4000;
	uuid_pack(&uu, out);
	out += sizeof(UUID_FIELD);
	}
	}

	void uuid_generate_random(UUID_FIELD out)
	{
	int num = 1;
	/* No real reason to use the daemon for random uuid's -- yet */

	__uuid_generate_random(out, &num);
	}

	/*
	* Check whether good random source (/dev/random or /dev/urandom)
	* is available.
	*/
	static int have_random_source(void)
	{
	struct stat s;

	return (!stat("/dev/random", &s) \|\| !stat("/dev/urandom", &s));
	}


	/*
	* This is the generic front-end to uuid_generate_random and
	* uuid_generate_time. It uses uuid_generate_random only if
	* /dev/urandom is available, since otherwise we won't have
	* high-quality randomness.
	*/
	void uuid_generate(UUID_FIELD out)
	{
	if (have_random_source())
	uuid_generate_random(out);
	else
	uuid_generate_time(out);
	}