From: Florian Forster <octo@collectd.org>
Date: Thu, 26 Nov 2015 13:22:20 +0000 (+0100)
Subject: Merge branch 'collectd-5.4' into collectd-5.5
X-Git-Tag: collectd-5.5.1~48
X-Git-Url: https://git.verplant.org/?a=commitdiff_plain;h=fc6f1e3d33d646391adb5cedc62e7b3904c15003;p=collectd.git

Merge branch 'collectd-5.4' into collectd-5.5
---

fc6f1e3d33d646391adb5cedc62e7b3904c15003
diff --cc src/daemon/common.c
index b2448086,00000000..53c1f08a
mode 100644,000000..100644
--- a/src/daemon/common.c
+++ b/src/daemon/common.c
@@@ -1,1656 -1,0 +1,1672 @@@
 +/**
 + * collectd - src/common.c
 + * Copyright (C) 2005-2014  Florian octo Forster
 + *
 + * Permission is hereby granted, free of charge, to any person obtaining a
 + * copy of this software and associated documentation files (the "Software"),
 + * to deal in the Software without restriction, including without limitation
 + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 + * and/or sell copies of the Software, and to permit persons to whom the
 + * Software is furnished to do so, subject to the following conditions:
 + *
 + * The above copyright notice and this permission notice shall be included in
 + * all copies or substantial portions of the Software.
 + *
 + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 + * DEALINGS IN THE SOFTWARE.
 + *
 + * Authors:
 + *   Florian octo Forster <octo at collectd.org>
 + *   Niki W. Waibel <niki.waibel@gmx.net>
 + *   Sebastian Harl <sh at tokkee.org>
 + *   Michał Mirosław <mirq-linux at rere.qmqm.pl>
 +**/
 +
 +#if HAVE_CONFIG_H
 +# include "config.h"
 +#endif
 +
 +#include "collectd.h"
 +#include "common.h"
 +#include "plugin.h"
 +#include "utils_cache.h"
 +
 +#if HAVE_PTHREAD_H
 +# include <pthread.h>
 +#endif
 +
 +#ifdef HAVE_MATH_H
 +# include <math.h>
 +#endif
 +
 +/* for getaddrinfo */
 +#include <sys/types.h>
 +#include <sys/socket.h>
 +#include <netdb.h>
 +
++#include <poll.h>
++
 +#if HAVE_NETINET_IN_H
 +# include <netinet/in.h>
 +#endif
 +
 +/* for ntohl and htonl */
 +#if HAVE_ARPA_INET_H
 +# include <arpa/inet.h>
 +#endif
 +
 +#ifdef HAVE_LIBKSTAT
 +extern kstat_ctl_t *kc;
 +#endif
 +
 +#if !HAVE_GETPWNAM_R
 +static pthread_mutex_t getpwnam_r_lock = PTHREAD_MUTEX_INITIALIZER;
 +#endif
 +
 +#if !HAVE_STRERROR_R
 +static pthread_mutex_t strerror_r_lock = PTHREAD_MUTEX_INITIALIZER;
 +#endif
 +
 +char *sstrncpy (char *dest, const char *src, size_t n)
 +{
 +	strncpy (dest, src, n);
 +	dest[n - 1] = '\0';
 +
 +	return (dest);
 +} /* char *sstrncpy */
 +
 +int ssnprintf (char *dest, size_t n, const char *format, ...)
 +{
 +	int ret = 0;
 +	va_list ap;
 +
 +	va_start (ap, format);
 +	ret = vsnprintf (dest, n, format, ap);
 +	dest[n - 1] = '\0';
 +	va_end (ap);
 +
 +	return (ret);
 +} /* int ssnprintf */
 +
 +char *ssnprintf_alloc (char const *format, ...) /* {{{ */
 +{
 +	char static_buffer[1024] = "";
 +	char *alloc_buffer;
 +	size_t alloc_buffer_size;
 +	int status;
 +	va_list ap;
 +
 +	/* Try printing into the static buffer. In many cases it will be
 +	 * sufficiently large and we can simply return a strdup() of this
 +	 * buffer. */
 +	va_start (ap, format);
 +	status = vsnprintf (static_buffer, sizeof (static_buffer), format, ap);
 +	va_end (ap);
 +	if (status < 0)
 +		return (NULL);
 +
 +	/* "status" does not include the null byte. */
 +	alloc_buffer_size = (size_t) (status + 1);
 +	if (alloc_buffer_size <= sizeof (static_buffer))
 +		return (strdup (static_buffer));
 +
 +	/* Allocate a buffer large enough to hold the string. */
 +	alloc_buffer = malloc (alloc_buffer_size);
 +	if (alloc_buffer == NULL)
 +		return (NULL);
 +	memset (alloc_buffer, 0, alloc_buffer_size);
 +
 +	/* Print again into this new buffer. */
 +	va_start (ap, format);
 +	status = vsnprintf (alloc_buffer, alloc_buffer_size, format, ap);
 +	va_end (ap);
 +	if (status < 0)
 +	{
 +		sfree (alloc_buffer);
 +		return (NULL);
 +	}
 +
 +	return (alloc_buffer);
 +} /* }}} char *ssnprintf_alloc */
 +
 +char *sstrdup (const char *s)
 +{
 +	char *r;
 +	size_t sz;
 +
 +	if (s == NULL)
 +		return (NULL);
 +
 +	/* Do not use `strdup' here, because it's not specified in POSIX. It's
 +	 * ``only'' an XSI extension. */
 +	sz = strlen (s) + 1;
 +	r = (char *) malloc (sizeof (char) * sz);
 +	if (r == NULL)
 +	{
 +		ERROR ("sstrdup: Out of memory.");
 +		exit (3);
 +	}
 +	memcpy (r, s, sizeof (char) * sz);
 +
 +	return (r);
 +} /* char *sstrdup */
 +
 +/* Even though Posix requires "strerror_r" to return an "int",
 + * some systems (e.g. the GNU libc) return a "char *" _and_
 + * ignore the second argument ... -tokkee */
 +char *sstrerror (int errnum, char *buf, size_t buflen)
 +{
 +	buf[0] = '\0';
 +
 +#if !HAVE_STRERROR_R
 +	{
 +		char *temp;
 +
 +		pthread_mutex_lock (&strerror_r_lock);
 +
 +		temp = strerror (errnum);
 +		sstrncpy (buf, temp, buflen);
 +
 +		pthread_mutex_unlock (&strerror_r_lock);
 +	}
 +/* #endif !HAVE_STRERROR_R */
 +
 +#elif STRERROR_R_CHAR_P
 +	{
 +		char *temp;
 +		temp = strerror_r (errnum, buf, buflen);
 +		if (buf[0] == '\0')
 +		{
 +			if ((temp != NULL) && (temp != buf) && (temp[0] != '\0'))
 +				sstrncpy (buf, temp, buflen);
 +			else
 +				sstrncpy (buf, "strerror_r did not return "
 +						"an error message", buflen);
 +		}
 +	}
 +/* #endif STRERROR_R_CHAR_P */
 +
 +#else
 +	if (strerror_r (errnum, buf, buflen) != 0)
 +	{
 +		ssnprintf (buf, buflen, "Error #%i; "
 +				"Additionally, strerror_r failed.",
 +				errnum);
 +	}
 +#endif /* STRERROR_R_CHAR_P */
 +
 +	return (buf);
 +} /* char *sstrerror */
 +
 +void *smalloc (size_t size)
 +{
 +	void *r;
 +
 +	if ((r = malloc (size)) == NULL)
 +	{
 +		ERROR ("Not enough memory.");
 +		exit (3);
 +	}
 +
 +	return (r);
 +} /* void *smalloc */
 +
 +#if 0
 +void sfree (void **ptr)
 +{
 +	if (ptr == NULL)
 +		return;
 +
 +	if (*ptr != NULL)
 +		free (*ptr);
 +
 +	*ptr = NULL;
 +}
 +#endif
 +
 +ssize_t sread (int fd, void *buf, size_t count)
 +{
 +	char    *ptr;
 +	size_t   nleft;
 +	ssize_t  status;
 +
 +	ptr   = (char *) buf;
 +	nleft = count;
 +
 +	while (nleft > 0)
 +	{
 +		status = read (fd, (void *) ptr, nleft);
 +
 +		if ((status < 0) && ((errno == EAGAIN) || (errno == EINTR)))
 +			continue;
 +
 +		if (status < 0)
 +			return (status);
 +
 +		if (status == 0)
 +		{
 +			DEBUG ("Received EOF from fd %i. "
 +					"Closing fd and returning error.",
 +					fd);
 +			close (fd);
 +			return (-1);
 +		}
 +
 +		assert ((0 > status) || (nleft >= (size_t)status));
 +
 +		nleft = nleft - status;
 +		ptr   = ptr   + status;
 +	}
 +
 +	return (0);
 +}
 +
 +
 +ssize_t swrite (int fd, const void *buf, size_t count)
 +{
 +	const char *ptr;
 +	size_t      nleft;
 +	ssize_t     status;
++	struct      pollfd pfd;
 +
 +	ptr   = (const char *) buf;
 +	nleft = count;
++	
++	/* checking for closed peer connection */
++	pfd.fd = fd;
++	pfd.events = POLLIN | POLLHUP;
++	pfd.revents = 0;
++	if (poll(&pfd, 1, 0) > 0) {
++		char buffer[32];
++		if (recv(fd, buffer, sizeof(buffer), MSG_PEEK | MSG_DONTWAIT) == 0) {
++			// if recv returns zero (even though poll() said there is data to be read),
++			// that means the connection has been closed
++			return -1;
++		}
++	}
 +
 +	while (nleft > 0)
 +	{
 +		status = write (fd, (const void *) ptr, nleft);
 +
 +		if ((status < 0) && ((errno == EAGAIN) || (errno == EINTR)))
 +			continue;
 +
 +		if (status < 0)
 +			return (status);
 +
 +		nleft = nleft - status;
 +		ptr   = ptr   + status;
 +	}
 +
 +	return (0);
 +}
 +
 +int strsplit (char *string, char **fields, size_t size)
 +{
 +	size_t i;
 +	char *ptr;
 +	char *saveptr;
 +
 +	i = 0;
 +	ptr = string;
 +	saveptr = NULL;
 +	while ((fields[i] = strtok_r (ptr, " \t\r\n", &saveptr)) != NULL)
 +	{
 +		ptr = NULL;
 +		i++;
 +
 +		if (i >= size)
 +			break;
 +	}
 +
 +	return ((int) i);
 +}
 +
 +int strjoin (char *buffer, size_t buffer_size,
 +		char **fields, size_t fields_num,
 +		const char *sep)
 +{
 +	size_t avail;
 +	char *ptr;
 +	size_t sep_len;
 +	size_t i;
 +
 +	if ((buffer_size < 1) || (fields_num <= 0))
 +		return (-1);
 +
 +	memset (buffer, 0, buffer_size);
 +	ptr = buffer;
 +	avail = buffer_size - 1;
 +
 +	sep_len = 0;
 +	if (sep != NULL)
 +		sep_len = strlen (sep);
 +
 +	for (i = 0; i < fields_num; i++)
 +	{
 +		size_t field_len;
 +
 +		if ((i > 0) && (sep_len > 0))
 +		{
 +			if (avail < sep_len)
 +				return (-1);
 +
 +			memcpy (ptr, sep, sep_len);
 +			ptr += sep_len;
 +			avail -= sep_len;
 +		}
 +
 +		field_len = strlen (fields[i]);
 +		if (avail < field_len)
 +			return (-1);
 +
 +		memcpy (ptr, fields[i], field_len);
 +		ptr += field_len;
 +		avail -= field_len;
 +	}
 +
 +	assert (buffer[buffer_size - 1] == 0);
 +	return (strlen (buffer));
 +}
 +
 +int strsubstitute (char *str, char c_from, char c_to)
 +{
 +	int ret;
 +
 +	if (str == NULL)
 +		return (-1);
 +
 +	ret = 0;
 +	while (*str != '\0')
 +	{
 +		if (*str == c_from)
 +		{
 +			*str = c_to;
 +			ret++;
 +		}
 +		str++;
 +	}
 +
 +	return (ret);
 +} /* int strsubstitute */
 +
 +int escape_string (char *buffer, size_t buffer_size)
 +{
 +  char *temp;
 +  size_t i;
 +  size_t j;
 +
 +  /* Check if we need to escape at all first */
 +  temp = strpbrk (buffer, " \t\"\\");
 +  if (temp == NULL)
 +    return (0);
 +
 +  if (buffer_size < 3)
 +    return (EINVAL);
 +
 +  temp = (char *) malloc (buffer_size);
 +  if (temp == NULL)
 +    return (ENOMEM);
 +  memset (temp, 0, buffer_size);
 +
 +  temp[0] = '"';
 +  j = 1;
 +
 +  for (i = 0; i < buffer_size; i++)
 +  {
 +    if (buffer[i] == 0)
 +    {
 +      break;
 +    }
 +    else if ((buffer[i] == '"') || (buffer[i] == '\\'))
 +    {
 +      if (j > (buffer_size - 4))
 +        break;
 +      temp[j] = '\\';
 +      temp[j + 1] = buffer[i];
 +      j += 2;
 +    }
 +    else
 +    {
 +      if (j > (buffer_size - 3))
 +        break;
 +      temp[j] = buffer[i];
 +      j++;
 +    }
 +  }
 +
 +  assert ((j + 1) < buffer_size);
 +  temp[j] = '"';
 +  temp[j + 1] = 0;
 +
 +  sstrncpy (buffer, temp, buffer_size);
 +  sfree (temp);
 +  return (0);
 +} /* int escape_string */
 +
 +int strunescape (char *buf, size_t buf_len)
 +{
 +	size_t i;
 +
 +	for (i = 0; (i < buf_len) && (buf[i] != '\0'); ++i)
 +	{
 +		if (buf[i] != '\\')
 +			continue;
 +
 +		if (((i + 1) >= buf_len) || (buf[i + 1] == 0)) {
 +			ERROR ("string unescape: backslash found at end of string.");
 +			/* Ensure null-byte at the end of the buffer. */
 +			buf[i] = 0;
 +			return (-1);
 +		}
 +
 +		switch (buf[i + 1]) {
 +			case 't':
 +				buf[i] = '\t';
 +				break;
 +			case 'n':
 +				buf[i] = '\n';
 +				break;
 +			case 'r':
 +				buf[i] = '\r';
 +				break;
 +			default:
 +				buf[i] = buf[i + 1];
 +				break;
 +		}
 +
 +		/* Move everything after the position one position to the left.
 +		 * Add a null-byte as last character in the buffer. */
 +		memmove (buf + i + 1, buf + i + 2, buf_len - i - 2);
 +		buf[buf_len - 1] = 0;
 +	}
 +	return (0);
 +} /* int strunescape */
 +
 +size_t strstripnewline (char *buffer)
 +{
 +	size_t buffer_len = strlen (buffer);
 +
 +	while (buffer_len > 0)
 +	{
 +		if ((buffer[buffer_len - 1] != '\n')
 +				&& (buffer[buffer_len - 1] != '\r'))
 +			break;
 +		buffer_len--;
 +		buffer[buffer_len] = 0;
 +	}
 +
 +	return (buffer_len);
 +} /* size_t strstripnewline */
 +
 +int escape_slashes (char *buffer, size_t buffer_size)
 +{
 +	int i;
 +	size_t buffer_len;
 +
 +	buffer_len = strlen (buffer);
 +
 +	if (buffer_len <= 1)
 +	{
 +		if (strcmp ("/", buffer) == 0)
 +		{
 +			if (buffer_size < 5)
 +				return (-1);
 +			sstrncpy (buffer, "root", buffer_size);
 +		}
 +		return (0);
 +	}
 +
 +	/* Move one to the left */
 +	if (buffer[0] == '/')
 +	{
 +		memmove (buffer, buffer + 1, buffer_len);
 +		buffer_len--;
 +	}
 +
 +	for (i = 0; i < buffer_len; i++)
 +	{
 +		if (buffer[i] == '/')
 +			buffer[i] = '_';
 +	}
 +
 +	return (0);
 +} /* int escape_slashes */
 +
 +void replace_special (char *buffer, size_t buffer_size)
 +{
 +	size_t i;
 +
 +	for (i = 0; i < buffer_size; i++)
 +	{
 +		if (buffer[i] == 0)
 +			return;
 +		if ((!isalnum ((int) buffer[i])) && (buffer[i] != '-'))
 +			buffer[i] = '_';
 +	}
 +} /* void replace_special */
 +
 +int timeval_cmp (struct timeval tv0, struct timeval tv1, struct timeval *delta)
 +{
 +	struct timeval *larger;
 +	struct timeval *smaller;
 +
 +	int status;
 +
 +	NORMALIZE_TIMEVAL (tv0);
 +	NORMALIZE_TIMEVAL (tv1);
 +
 +	if ((tv0.tv_sec == tv1.tv_sec) && (tv0.tv_usec == tv1.tv_usec))
 +	{
 +		if (delta != NULL) {
 +			delta->tv_sec  = 0;
 +			delta->tv_usec = 0;
 +		}
 +		return (0);
 +	}
 +
 +	if ((tv0.tv_sec < tv1.tv_sec)
 +			|| ((tv0.tv_sec == tv1.tv_sec) && (tv0.tv_usec < tv1.tv_usec)))
 +	{
 +		larger  = &tv1;
 +		smaller = &tv0;
 +		status  = -1;
 +	}
 +	else
 +	{
 +		larger  = &tv0;
 +		smaller = &tv1;
 +		status  = 1;
 +	}
 +
 +	if (delta != NULL) {
 +		delta->tv_sec = larger->tv_sec - smaller->tv_sec;
 +
 +		if (smaller->tv_usec <= larger->tv_usec)
 +			delta->tv_usec = larger->tv_usec - smaller->tv_usec;
 +		else
 +		{
 +			--delta->tv_sec;
 +			delta->tv_usec = 1000000 + larger->tv_usec - smaller->tv_usec;
 +		}
 +	}
 +
 +	assert ((delta == NULL)
 +			|| ((0 <= delta->tv_usec) && (delta->tv_usec < 1000000)));
 +
 +	return (status);
 +} /* int timeval_cmp */
 +
 +int check_create_dir (const char *file_orig)
 +{
 +	struct stat statbuf;
 +
 +	char  file_copy[512];
 +	char  dir[512];
 +	int   dir_len = 512;
 +	char *fields[16];
 +	int   fields_num;
 +	char *ptr;
 +	char *saveptr;
 +	int   last_is_file = 1;
 +	int   path_is_absolute = 0;
 +	size_t len;
 +	int   i;
 +
 +	/*
 +	 * Sanity checks first
 +	 */
 +	if (file_orig == NULL)
 +		return (-1);
 +
 +	if ((len = strlen (file_orig)) < 1)
 +		return (-1);
 +	else if (len >= sizeof (file_copy))
 +		return (-1);
 +
 +	/*
 +	 * If `file_orig' ends in a slash the last component is a directory,
 +	 * otherwise it's a file. Act accordingly..
 +	 */
 +	if (file_orig[len - 1] == '/')
 +		last_is_file = 0;
 +	if (file_orig[0] == '/')
 +		path_is_absolute = 1;
 +
 +	/*
 +	 * Create a copy for `strtok_r' to destroy
 +	 */
 +	sstrncpy (file_copy, file_orig, sizeof (file_copy));
 +
 +	/*
 +	 * Break into components. This will eat up several slashes in a row and
 +	 * remove leading and trailing slashes..
 +	 */
 +	ptr = file_copy;
 +	saveptr = NULL;
 +	fields_num = 0;
 +	while ((fields[fields_num] = strtok_r (ptr, "/", &saveptr)) != NULL)
 +	{
 +		ptr = NULL;
 +		fields_num++;
 +
 +		if (fields_num >= 16)
 +			break;
 +	}
 +
 +	/*
 +	 * For each component, do..
 +	 */
 +	for (i = 0; i < (fields_num - last_is_file); i++)
 +	{
 +		/*
 +		 * Do not create directories that start with a dot. This
 +		 * prevents `../../' attacks and other likely malicious
 +		 * behavior.
 +		 */
 +		if (fields[i][0] == '.')
 +		{
 +			ERROR ("Cowardly refusing to create a directory that "
 +					"begins with a `.' (dot): `%s'", file_orig);
 +			return (-2);
 +		}
 +
 +		/*
 +		 * Join the components together again
 +		 */
 +		dir[0] = '/';
 +		if (strjoin (dir + path_is_absolute, dir_len - path_is_absolute,
 +					fields, i + 1, "/") < 0)
 +		{
 +			ERROR ("strjoin failed: `%s', component #%i", file_orig, i);
 +			return (-1);
 +		}
 +
 +		while (42) {
 +			if ((stat (dir, &statbuf) == -1)
 +					&& (lstat (dir, &statbuf) == -1))
 +			{
 +				if (errno == ENOENT)
 +				{
 +					if (mkdir (dir, S_IRWXU | S_IRWXG | S_IRWXO) == 0)
 +						break;
 +
 +					/* this might happen, if a different thread created
 +					 * the directory in the meantime
 +					 * => call stat() again to check for S_ISDIR() */
 +					if (EEXIST == errno)
 +						continue;
 +
 +					char errbuf[1024];
 +					ERROR ("check_create_dir: mkdir (%s): %s", dir,
 +							sstrerror (errno,
 +								errbuf, sizeof (errbuf)));
 +					return (-1);
 +				}
 +				else
 +				{
 +					char errbuf[1024];
 +					ERROR ("check_create_dir: stat (%s): %s", dir,
 +							sstrerror (errno, errbuf,
 +								sizeof (errbuf)));
 +					return (-1);
 +				}
 +			}
 +			else if (!S_ISDIR (statbuf.st_mode))
 +			{
 +				ERROR ("check_create_dir: `%s' exists but is not "
 +						"a directory!", dir);
 +				return (-1);
 +			}
 +			break;
 +		}
 +	}
 +
 +	return (0);
 +} /* check_create_dir */
 +
 +#ifdef HAVE_LIBKSTAT
 +int get_kstat (kstat_t **ksp_ptr, char *module, int instance, char *name)
 +{
 +	char ident[128];
 +
 +	*ksp_ptr = NULL;
 +
 +	if (kc == NULL)
 +		return (-1);
 +
 +	ssnprintf (ident, sizeof (ident), "%s,%i,%s", module, instance, name);
 +
 +	*ksp_ptr = kstat_lookup (kc, module, instance, name);
 +	if (*ksp_ptr == NULL)
 +	{
 +		ERROR ("get_kstat: Cound not find kstat %s", ident);
 +		return (-1);
 +	}
 +
 +	if ((*ksp_ptr)->ks_type != KSTAT_TYPE_NAMED)
 +	{
 +		ERROR ("get_kstat: kstat %s has wrong type", ident);
 +		*ksp_ptr = NULL;
 +		return (-1);
 +	}
 +
 +#ifdef assert
 +	assert (*ksp_ptr != NULL);
 +	assert ((*ksp_ptr)->ks_type == KSTAT_TYPE_NAMED);
 +#endif
 +
 +	if (kstat_read (kc, *ksp_ptr, NULL) == -1)
 +	{
 +		ERROR ("get_kstat: kstat %s could not be read", ident);
 +		return (-1);
 +	}
 +
 +	if ((*ksp_ptr)->ks_type != KSTAT_TYPE_NAMED)
 +	{
 +		ERROR ("get_kstat: kstat %s has wrong type", ident);
 +		return (-1);
 +	}
 +
 +	return (0);
 +}
 +
 +long long get_kstat_value (kstat_t *ksp, char *name)
 +{
 +	kstat_named_t *kn;
 +	long long retval = -1LL;
 +
 +	if (ksp == NULL)
 +	{
 +		ERROR ("get_kstat_value (\"%s\"): ksp is NULL.", name);
 +		return (-1LL);
 +	}
 +	else if (ksp->ks_type != KSTAT_TYPE_NAMED)
 +	{
 +		ERROR ("get_kstat_value (\"%s\"): ksp->ks_type (%#x) "
 +				"is not KSTAT_TYPE_NAMED (%#x).",
 +				name,
 +				(unsigned int) ksp->ks_type,
 +				(unsigned int) KSTAT_TYPE_NAMED);
 +		return (-1LL);
 +	}
 +
 +	if ((kn = (kstat_named_t *) kstat_data_lookup (ksp, name)) == NULL)
 +		return (-1LL);
 +
 +	if (kn->data_type == KSTAT_DATA_INT32)
 +		retval = (long long) kn->value.i32;
 +	else if (kn->data_type == KSTAT_DATA_UINT32)
 +		retval = (long long) kn->value.ui32;
 +	else if (kn->data_type == KSTAT_DATA_INT64)
 +		retval = (long long) kn->value.i64; /* According to ANSI C99 `long long' must hold at least 64 bits */
 +	else if (kn->data_type == KSTAT_DATA_UINT64)
 +		retval = (long long) kn->value.ui64; /* XXX: Might overflow! */
 +	else
 +		WARNING ("get_kstat_value: Not a numeric value: %s", name);
 +
 +	return (retval);
 +}
 +#endif /* HAVE_LIBKSTAT */
 +
 +#ifndef HAVE_HTONLL
 +unsigned long long ntohll (unsigned long long n)
 +{
 +#if BYTE_ORDER == BIG_ENDIAN
 +	return (n);
 +#else
 +	return (((unsigned long long) ntohl (n)) << 32) + ntohl (n >> 32);
 +#endif
 +} /* unsigned long long ntohll */
 +
 +unsigned long long htonll (unsigned long long n)
 +{
 +#if BYTE_ORDER == BIG_ENDIAN
 +	return (n);
 +#else
 +	return (((unsigned long long) htonl (n)) << 32) + htonl (n >> 32);
 +#endif
 +} /* unsigned long long htonll */
 +#endif /* HAVE_HTONLL */
 +
 +#if FP_LAYOUT_NEED_NOTHING
 +/* Well, we need nothing.. */
 +/* #endif FP_LAYOUT_NEED_NOTHING */
 +
 +#elif FP_LAYOUT_NEED_ENDIANFLIP || FP_LAYOUT_NEED_INTSWAP
 +# if FP_LAYOUT_NEED_ENDIANFLIP
 +#  define FP_CONVERT(A) ((((uint64_t)(A) & 0xff00000000000000LL) >> 56) | \
 +                         (((uint64_t)(A) & 0x00ff000000000000LL) >> 40) | \
 +                         (((uint64_t)(A) & 0x0000ff0000000000LL) >> 24) | \
 +                         (((uint64_t)(A) & 0x000000ff00000000LL) >> 8)  | \
 +                         (((uint64_t)(A) & 0x00000000ff000000LL) << 8)  | \
 +                         (((uint64_t)(A) & 0x0000000000ff0000LL) << 24) | \
 +                         (((uint64_t)(A) & 0x000000000000ff00LL) << 40) | \
 +                         (((uint64_t)(A) & 0x00000000000000ffLL) << 56))
 +# else
 +#  define FP_CONVERT(A) ((((uint64_t)(A) & 0xffffffff00000000LL) >> 32) | \
 +                         (((uint64_t)(A) & 0x00000000ffffffffLL) << 32))
 +# endif
 +
 +double ntohd (double d)
 +{
 +	union
 +	{
 +		uint8_t  byte[8];
 +		uint64_t integer;
 +		double   floating;
 +	} ret;
 +
 +	ret.floating = d;
 +
 +	/* NAN in x86 byte order */
 +	if ((ret.byte[0] == 0x00) && (ret.byte[1] == 0x00)
 +			&& (ret.byte[2] == 0x00) && (ret.byte[3] == 0x00)
 +			&& (ret.byte[4] == 0x00) && (ret.byte[5] == 0x00)
 +			&& (ret.byte[6] == 0xf8) && (ret.byte[7] == 0x7f))
 +	{
 +		return (NAN);
 +	}
 +	else
 +	{
 +		uint64_t tmp;
 +
 +		tmp = ret.integer;
 +		ret.integer = FP_CONVERT (tmp);
 +		return (ret.floating);
 +	}
 +} /* double ntohd */
 +
 +double htond (double d)
 +{
 +	union
 +	{
 +		uint8_t  byte[8];
 +		uint64_t integer;
 +		double   floating;
 +	} ret;
 +
 +	if (isnan (d))
 +	{
 +		ret.byte[0] = ret.byte[1] = ret.byte[2] = ret.byte[3] = 0x00;
 +		ret.byte[4] = ret.byte[5] = 0x00;
 +		ret.byte[6] = 0xf8;
 +		ret.byte[7] = 0x7f;
 +		return (ret.floating);
 +	}
 +	else
 +	{
 +		uint64_t tmp;
 +
 +		ret.floating = d;
 +		tmp = FP_CONVERT (ret.integer);
 +		ret.integer = tmp;
 +		return (ret.floating);
 +	}
 +} /* double htond */
 +#endif /* FP_LAYOUT_NEED_ENDIANFLIP || FP_LAYOUT_NEED_INTSWAP */
 +
 +int format_name (char *ret, int ret_len,
 +		const char *hostname,
 +		const char *plugin, const char *plugin_instance,
 +		const char *type, const char *type_instance)
 +{
 +  char *buffer;
 +  size_t buffer_size;
 +
 +  buffer = ret;
 +  buffer_size = (size_t) ret_len;
 +
 +#define APPEND(str) do {                                               \
 +  size_t l = strlen (str);                                             \
 +  if (l >= buffer_size)                                                \
 +    return (ENOBUFS);                                                  \
 +  memcpy (buffer, (str), l);                                           \
 +  buffer += l; buffer_size -= l;                                       \
 +} while (0)
 +
 +  assert (plugin != NULL);
 +  assert (type != NULL);
 +
 +  APPEND (hostname);
 +  APPEND ("/");
 +  APPEND (plugin);
 +  if ((plugin_instance != NULL) && (plugin_instance[0] != 0))
 +  {
 +    APPEND ("-");
 +    APPEND (plugin_instance);
 +  }
 +  APPEND ("/");
 +  APPEND (type);
 +  if ((type_instance != NULL) && (type_instance[0] != 0))
 +  {
 +    APPEND ("-");
 +    APPEND (type_instance);
 +  }
 +  assert (buffer_size > 0);
 +  buffer[0] = 0;
 +
 +#undef APPEND
 +  return (0);
 +} /* int format_name */
 +
 +int format_values (char *ret, size_t ret_len, /* {{{ */
 +		const data_set_t *ds, const value_list_t *vl,
 +		_Bool store_rates)
 +{
 +        size_t offset = 0;
 +        int status;
 +        int i;
 +        gauge_t *rates = NULL;
 +
 +        assert (0 == strcmp (ds->type, vl->type));
 +
 +        memset (ret, 0, ret_len);
 +
 +#define BUFFER_ADD(...) do { \
 +        status = ssnprintf (ret + offset, ret_len - offset, \
 +                        __VA_ARGS__); \
 +        if (status < 1) \
 +        { \
 +                sfree (rates); \
 +                return (-1); \
 +        } \
 +        else if (((size_t) status) >= (ret_len - offset)) \
 +        { \
 +                sfree (rates); \
 +                return (-1); \
 +        } \
 +        else \
 +                offset += ((size_t) status); \
 +} while (0)
 +
 +        BUFFER_ADD ("%.3f", CDTIME_T_TO_DOUBLE (vl->time));
 +
 +        for (i = 0; i < ds->ds_num; i++)
 +        {
 +                if (ds->ds[i].type == DS_TYPE_GAUGE)
 +                        BUFFER_ADD (":"GAUGE_FORMAT, vl->values[i].gauge);
 +                else if (store_rates)
 +                {
 +                        if (rates == NULL)
 +                                rates = uc_get_rate (ds, vl);
 +                        if (rates == NULL)
 +                        {
 +                                WARNING ("format_values: uc_get_rate failed.");
 +                                return (-1);
 +                        }
 +                        BUFFER_ADD (":"GAUGE_FORMAT, rates[i]);
 +                }
 +                else if (ds->ds[i].type == DS_TYPE_COUNTER)
 +                        BUFFER_ADD (":%llu", vl->values[i].counter);
 +                else if (ds->ds[i].type == DS_TYPE_DERIVE)
 +                        BUFFER_ADD (":%"PRIi64, vl->values[i].derive);
 +                else if (ds->ds[i].type == DS_TYPE_ABSOLUTE)
 +                        BUFFER_ADD (":%"PRIu64, vl->values[i].absolute);
 +                else
 +                {
 +                        ERROR ("format_values: Unknown data source type: %i",
 +                                        ds->ds[i].type);
 +                        sfree (rates);
 +                        return (-1);
 +                }
 +        } /* for ds->ds_num */
 +
 +#undef BUFFER_ADD
 +
 +        sfree (rates);
 +        return (0);
 +} /* }}} int format_values */
 +
 +int parse_identifier (char *str, char **ret_host,
 +		char **ret_plugin, char **ret_plugin_instance,
 +		char **ret_type, char **ret_type_instance)
 +{
 +	char *hostname = NULL;
 +	char *plugin = NULL;
 +	char *plugin_instance = NULL;
 +	char *type = NULL;
 +	char *type_instance = NULL;
 +
 +	hostname = str;
 +	if (hostname == NULL)
 +		return (-1);
 +
 +	plugin = strchr (hostname, '/');
 +	if (plugin == NULL)
 +		return (-1);
 +	*plugin = '\0'; plugin++;
 +
 +	type = strchr (plugin, '/');
 +	if (type == NULL)
 +		return (-1);
 +	*type = '\0'; type++;
 +
 +	plugin_instance = strchr (plugin, '-');
 +	if (plugin_instance != NULL)
 +	{
 +		*plugin_instance = '\0';
 +		plugin_instance++;
 +	}
 +
 +	type_instance = strchr (type, '-');
 +	if (type_instance != NULL)
 +	{
 +		*type_instance = '\0';
 +		type_instance++;
 +	}
 +
 +	*ret_host = hostname;
 +	*ret_plugin = plugin;
 +	*ret_plugin_instance = plugin_instance;
 +	*ret_type = type;
 +	*ret_type_instance = type_instance;
 +	return (0);
 +} /* int parse_identifier */
 +
 +int parse_identifier_vl (const char *str, value_list_t *vl) /* {{{ */
 +{
 +	char str_copy[6 * DATA_MAX_NAME_LEN];
 +	char *host = NULL;
 +	char *plugin = NULL;
 +	char *plugin_instance = NULL;
 +	char *type = NULL;
 +	char *type_instance = NULL;
 +	int status;
 +
 +	if ((str == NULL) || (vl == NULL))
 +		return (EINVAL);
 +
 +	sstrncpy (str_copy, str, sizeof (str_copy));
 +
 +	status = parse_identifier (str_copy, &host,
 +			&plugin, &plugin_instance,
 +			&type, &type_instance);
 +	if (status != 0)
 +		return (status);
 +
 +	sstrncpy (vl->host, host, sizeof (vl->host));
 +	sstrncpy (vl->plugin, plugin, sizeof (vl->plugin));
 +	sstrncpy (vl->plugin_instance,
 +			(plugin_instance != NULL) ? plugin_instance : "",
 +			sizeof (vl->plugin_instance));
 +	sstrncpy (vl->type, type, sizeof (vl->type));
 +	sstrncpy (vl->type_instance,
 +			(type_instance != NULL) ? type_instance : "",
 +			sizeof (vl->type_instance));
 +
 +	return (0);
 +} /* }}} int parse_identifier_vl */
 +
 +int parse_value (const char *value_orig, value_t *ret_value, int ds_type)
 +{
 +  char *value;
 +  char *endptr = NULL;
 +  size_t value_len;
 +
 +  if (value_orig == NULL)
 +    return (EINVAL);
 +
 +  value = strdup (value_orig);
 +  if (value == NULL)
 +    return (ENOMEM);
 +  value_len = strlen (value);
 +
 +  while ((value_len > 0) && isspace ((int) value[value_len - 1]))
 +  {
 +    value[value_len - 1] = 0;
 +    value_len--;
 +  }
 +
 +  switch (ds_type)
 +  {
 +    case DS_TYPE_COUNTER:
 +      ret_value->counter = (counter_t) strtoull (value, &endptr, 0);
 +      break;
 +
 +    case DS_TYPE_GAUGE:
 +      ret_value->gauge = (gauge_t) strtod (value, &endptr);
 +      break;
 +
 +    case DS_TYPE_DERIVE:
 +      ret_value->derive = (derive_t) strtoll (value, &endptr, 0);
 +      break;
 +
 +    case DS_TYPE_ABSOLUTE:
 +      ret_value->absolute = (absolute_t) strtoull (value, &endptr, 0);
 +      break;
 +
 +    default:
 +      sfree (value);
 +      ERROR ("parse_value: Invalid data source type: %i.", ds_type);
 +      return -1;
 +  }
 +
 +  if (value == endptr) {
 +    ERROR ("parse_value: Failed to parse string as %s: %s.",
 +        DS_TYPE_TO_STRING (ds_type), value);
 +    sfree (value);
 +    return -1;
 +  }
 +  else if ((NULL != endptr) && ('\0' != *endptr))
 +    INFO ("parse_value: Ignoring trailing garbage \"%s\" after %s value. "
 +        "Input string was \"%s\".",
 +        endptr, DS_TYPE_TO_STRING (ds_type), value_orig);
 +
 +  sfree (value);
 +  return 0;
 +} /* int parse_value */
 +
 +int parse_values (char *buffer, value_list_t *vl, const data_set_t *ds)
 +{
 +	int i;
 +	char *dummy;
 +	char *ptr;
 +	char *saveptr;
 +
 +	i = -1;
 +	dummy = buffer;
 +	saveptr = NULL;
 +	while ((ptr = strtok_r (dummy, ":", &saveptr)) != NULL)
 +	{
 +		dummy = NULL;
 +
 +		if (i >= vl->values_len)
 +		{
 +			/* Make sure i is invalid. */
 +			i = vl->values_len + 1;
 +			break;
 +		}
 +
 +		if (i == -1)
 +		{
 +			if (strcmp ("N", ptr) == 0)
 +				vl->time = cdtime ();
 +			else
 +			{
 +				char *endptr = NULL;
 +				double tmp;
 +
 +				errno = 0;
 +				tmp = strtod (ptr, &endptr);
 +				if ((errno != 0)                    /* Overflow */
 +						|| (endptr == ptr)  /* Invalid string */
 +						|| (endptr == NULL) /* This should not happen */
 +						|| (*endptr != 0))  /* Trailing chars */
 +					return (-1);
 +
 +				vl->time = DOUBLE_TO_CDTIME_T (tmp);
 +			}
 +		}
 +		else
 +		{
 +			if ((strcmp ("U", ptr) == 0) && (ds->ds[i].type == DS_TYPE_GAUGE))
 +				vl->values[i].gauge = NAN;
 +			else if (0 != parse_value (ptr, &vl->values[i], ds->ds[i].type))
 +				return -1;
 +		}
 +
 +		i++;
 +	} /* while (strtok_r) */
 +
 +	if ((ptr != NULL) || (i != vl->values_len))
 +		return (-1);
 +	return (0);
 +} /* int parse_values */
 +
 +#if !HAVE_GETPWNAM_R
 +int getpwnam_r (const char *name, struct passwd *pwbuf, char *buf,
 +		size_t buflen, struct passwd **pwbufp)
 +{
 +	int status = 0;
 +	struct passwd *pw;
 +
 +	memset (pwbuf, '\0', sizeof (struct passwd));
 +
 +	pthread_mutex_lock (&getpwnam_r_lock);
 +
 +	do
 +	{
 +		pw = getpwnam (name);
 +		if (pw == NULL)
 +		{
 +			status = (errno != 0) ? errno : ENOENT;
 +			break;
 +		}
 +
 +#define GETPWNAM_COPY_MEMBER(member) \
 +		if (pw->member != NULL) \
 +		{ \
 +			int len = strlen (pw->member); \
 +			if (len >= buflen) \
 +			{ \
 +				status = ENOMEM; \
 +				break; \
 +			} \
 +			sstrncpy (buf, pw->member, buflen); \
 +			pwbuf->member = buf; \
 +			buf    += (len + 1); \
 +			buflen -= (len + 1); \
 +		}
 +		GETPWNAM_COPY_MEMBER(pw_name);
 +		GETPWNAM_COPY_MEMBER(pw_passwd);
 +		GETPWNAM_COPY_MEMBER(pw_gecos);
 +		GETPWNAM_COPY_MEMBER(pw_dir);
 +		GETPWNAM_COPY_MEMBER(pw_shell);
 +
 +		pwbuf->pw_uid = pw->pw_uid;
 +		pwbuf->pw_gid = pw->pw_gid;
 +
 +		if (pwbufp != NULL)
 +			*pwbufp = pwbuf;
 +	} while (0);
 +
 +	pthread_mutex_unlock (&getpwnam_r_lock);
 +
 +	return (status);
 +} /* int getpwnam_r */
 +#endif /* !HAVE_GETPWNAM_R */
 +
 +int notification_init (notification_t *n, int severity, const char *message,
 +		const char *host,
 +		const char *plugin, const char *plugin_instance,
 +		const char *type, const char *type_instance)
 +{
 +	memset (n, '\0', sizeof (notification_t));
 +
 +	n->severity = severity;
 +
 +	if (message != NULL)
 +		sstrncpy (n->message, message, sizeof (n->message));
 +	if (host != NULL)
 +		sstrncpy (n->host, host, sizeof (n->host));
 +	if (plugin != NULL)
 +		sstrncpy (n->plugin, plugin, sizeof (n->plugin));
 +	if (plugin_instance != NULL)
 +		sstrncpy (n->plugin_instance, plugin_instance,
 +				sizeof (n->plugin_instance));
 +	if (type != NULL)
 +		sstrncpy (n->type, type, sizeof (n->type));
 +	if (type_instance != NULL)
 +		sstrncpy (n->type_instance, type_instance,
 +				sizeof (n->type_instance));
 +
 +	return (0);
 +} /* int notification_init */
 +
 +int walk_directory (const char *dir, dirwalk_callback_f callback,
 +		void *user_data, int include_hidden)
 +{
 +	struct dirent *ent;
 +	DIR *dh;
 +	int success;
 +	int failure;
 +
 +	success = 0;
 +	failure = 0;
 +
 +	if ((dh = opendir (dir)) == NULL)
 +	{
 +		char errbuf[1024];
 +		ERROR ("walk_directory: Cannot open '%s': %s", dir,
 +				sstrerror (errno, errbuf, sizeof (errbuf)));
 +		return -1;
 +	}
 +
 +	while ((ent = readdir (dh)) != NULL)
 +	{
 +		int status;
 +
 +		if (include_hidden)
 +		{
 +			if ((strcmp (".", ent->d_name) == 0)
 +					|| (strcmp ("..", ent->d_name) == 0))
 +				continue;
 +		}
 +		else /* if (!include_hidden) */
 +		{
 +			if (ent->d_name[0]=='.')
 +				continue;
 +		}
 +
 +		status = (*callback) (dir, ent->d_name, user_data);
 +		if (status != 0)
 +			failure++;
 +		else
 +			success++;
 +	}
 +
 +	closedir (dh);
 +
 +	if ((success == 0) && (failure > 0))
 +		return (-1);
 +	return (0);
 +}
 +
 +ssize_t read_file_contents (const char *filename, char *buf, size_t bufsize)
 +{
 +	FILE *fh;
 +	ssize_t ret;
 +
 +	fh = fopen (filename, "r");
 +	if (fh == NULL)
 +		return (-1);
 +
 +	ret = (ssize_t) fread (buf, 1, bufsize, fh);
 +	if ((ret == 0) && (ferror (fh) != 0))
 +	{
 +		ERROR ("read_file_contents: Reading file \"%s\" failed.",
 +				filename);
 +		ret = -1;
 +	}
 +
 +	fclose(fh);
 +	return (ret);
 +}
 +
 +counter_t counter_diff (counter_t old_value, counter_t new_value)
 +{
 +	counter_t diff;
 +
 +	if (old_value > new_value)
 +	{
 +		if (old_value <= 4294967295U)
 +			diff = (4294967295U - old_value) + new_value;
 +		else
 +			diff = (18446744073709551615ULL - old_value)
 +				+ new_value;
 +	}
 +	else
 +	{
 +		diff = new_value - old_value;
 +	}
 +
 +	return (diff);
 +} /* counter_t counter_diff */
 +
 +int rate_to_value (value_t *ret_value, gauge_t rate, /* {{{ */
 +		rate_to_value_state_t *state,
 +		int ds_type, cdtime_t t)
 +{
 +	gauge_t delta_gauge;
 +	cdtime_t delta_t;
 +
 +	if (ds_type == DS_TYPE_GAUGE)
 +	{
 +		state->last_value.gauge = rate;
 +		state->last_time = t;
 +
 +		*ret_value = state->last_value;
 +		return (0);
 +	}
 +
 +	/* Counter and absolute can't handle negative rates. Reset "last time"
 +	 * to zero, so that the next valid rate will re-initialize the
 +	 * structure. */
 +	if ((rate < 0.0)
 +			&& ((ds_type == DS_TYPE_COUNTER)
 +				|| (ds_type == DS_TYPE_ABSOLUTE)))
 +	{
 +		memset (state, 0, sizeof (*state));
 +		return (EINVAL);
 +	}
 +
 +	/* Another invalid state: The time is not increasing. */
 +	if (t <= state->last_time)
 +	{
 +		memset (state, 0, sizeof (*state));
 +		return (EINVAL);
 +	}
 +
 +	delta_t = t - state->last_time;
 +	delta_gauge = (rate * CDTIME_T_TO_DOUBLE (delta_t)) + state->residual;
 +
 +	/* Previous value is invalid. */
 +	if (state->last_time == 0) /* {{{ */
 +	{
 +		if (ds_type == DS_TYPE_DERIVE)
 +		{
 +			state->last_value.derive = (derive_t) rate;
 +			state->residual = rate - ((gauge_t) state->last_value.derive);
 +		}
 +		else if (ds_type == DS_TYPE_COUNTER)
 +		{
 +			state->last_value.counter = (counter_t) rate;
 +			state->residual = rate - ((gauge_t) state->last_value.counter);
 +		}
 +		else if (ds_type == DS_TYPE_ABSOLUTE)
 +		{
 +			state->last_value.absolute = (absolute_t) rate;
 +			state->residual = rate - ((gauge_t) state->last_value.absolute);
 +		}
 +		else
 +		{
 +			assert (23 == 42);
 +		}
 +
 +		state->last_time = t;
 +		return (EAGAIN);
 +	} /* }}} */
 +
 +	if (ds_type == DS_TYPE_DERIVE)
 +	{
 +		derive_t delta_derive = (derive_t) delta_gauge;
 +
 +		state->last_value.derive += delta_derive;
 +		state->residual = delta_gauge - ((gauge_t) delta_derive);
 +	}
 +	else if (ds_type == DS_TYPE_COUNTER)
 +	{
 +		counter_t delta_counter = (counter_t) delta_gauge;
 +
 +		state->last_value.counter += delta_counter;
 +		state->residual = delta_gauge - ((gauge_t) delta_counter);
 +	}
 +	else if (ds_type == DS_TYPE_ABSOLUTE)
 +	{
 +		absolute_t delta_absolute = (absolute_t) delta_gauge;
 +
 +		state->last_value.absolute = delta_absolute;
 +		state->residual = delta_gauge - ((gauge_t) delta_absolute);
 +	}
 +	else
 +	{
 +		assert (23 == 42);
 +	}
 +
 +        state->last_time = t;
 +	*ret_value = state->last_value;
 +	return (0);
 +} /* }}} value_t rate_to_value */
 +
 +int value_to_rate (value_t *ret_rate, derive_t value, /* {{{ */
 +		value_to_rate_state_t *state,
 +		int ds_type, cdtime_t t)
 +{
 +	double interval;
 +
 +	/* Another invalid state: The time is not increasing. */
 +	if (t <= state->last_time)
 +	{
 +		memset (state, 0, sizeof (*state));
 +		return (EINVAL);
 +	}
 +
 +	interval = CDTIME_T_TO_DOUBLE(t - state->last_time);
 +
 +	/* Previous value is invalid. */
 +	if (state->last_time == 0) /* {{{ */
 +	{
 +		if (ds_type == DS_TYPE_DERIVE)
 +		{
 +			state->last_value.derive = value;
 +		}
 +		else if (ds_type == DS_TYPE_COUNTER)
 +		{
 +			state->last_value.counter = (counter_t) value;
 +		}
 +		else if (ds_type == DS_TYPE_ABSOLUTE)
 +		{
 +			state->last_value.absolute = (absolute_t) value;
 +		}
 +		else
 +		{
 +			assert (23 == 42);
 +		}
 +
 +		state->last_time = t;
 +		return (EAGAIN);
 +	} /* }}} */
 +
 +	if (ds_type == DS_TYPE_DERIVE)
 +	{
 +		ret_rate->gauge = (value - state->last_value.derive) / interval;
 +		state->last_value.derive = value;
 +	}
 +	else if (ds_type == DS_TYPE_COUNTER)
 +	{
 +		ret_rate->gauge = (((counter_t)value) - state->last_value.counter) / interval;
 +		state->last_value.counter = (counter_t) value;
 +	}
 +	else if (ds_type == DS_TYPE_ABSOLUTE)
 +	{
 +		ret_rate->gauge = (((absolute_t)value) - state->last_value.absolute) / interval;
 +		state->last_value.absolute = (absolute_t) value;
 +	}
 +	else
 +	{
 +		assert (23 == 42);
 +	}
 +
 +        state->last_time = t;
 +	return (0);
 +} /* }}} value_t rate_to_value */
 +
 +int service_name_to_port_number (const char *service_name)
 +{
 +	struct addrinfo *ai_list;
 +	struct addrinfo *ai_ptr;
 +	struct addrinfo ai_hints;
 +	int status;
 +	int service_number;
 +
 +	if (service_name == NULL)
 +		return (-1);
 +
 +	ai_list = NULL;
 +	memset (&ai_hints, 0, sizeof (ai_hints));
 +	ai_hints.ai_family = AF_UNSPEC;
 +
 +	status = getaddrinfo (/* node = */ NULL, service_name,
 +			&ai_hints, &ai_list);
 +	if (status != 0)
 +	{
 +		ERROR ("service_name_to_port_number: getaddrinfo failed: %s",
 +				gai_strerror (status));
 +		return (-1);
 +	}
 +
 +	service_number = -1;
 +	for (ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next)
 +	{
 +		if (ai_ptr->ai_family == AF_INET)
 +		{
 +			struct sockaddr_in *sa;
 +
 +			sa = (void *) ai_ptr->ai_addr;
 +			service_number = (int) ntohs (sa->sin_port);
 +		}
 +		else if (ai_ptr->ai_family == AF_INET6)
 +		{
 +			struct sockaddr_in6 *sa;
 +
 +			sa = (void *) ai_ptr->ai_addr;
 +			service_number = (int) ntohs (sa->sin6_port);
 +		}
 +
 +		if ((service_number > 0) && (service_number <= 65535))
 +			break;
 +	}
 +
 +	freeaddrinfo (ai_list);
 +
 +	if ((service_number > 0) && (service_number <= 65535))
 +		return (service_number);
 +	return (-1);
 +} /* int service_name_to_port_number */
 +
 +int strtoderive (const char *string, derive_t *ret_value) /* {{{ */
 +{
 +	derive_t tmp;
 +	char *endptr;
 +
 +	if ((string == NULL) || (ret_value == NULL))
 +		return (EINVAL);
 +
 +	errno = 0;
 +	endptr = NULL;
 +	tmp = (derive_t) strtoll (string, &endptr, /* base = */ 0);
 +	if ((endptr == string) || (errno != 0))
 +		return (-1);
 +
 +	*ret_value = tmp;
 +	return (0);
 +} /* }}} int strtoderive */
 +
 +int strtogauge (const char *string, gauge_t *ret_value) /* {{{ */
 +{
 +	gauge_t tmp;
 +	char *endptr = NULL;
 +
 +	if ((string == NULL) || (ret_value == NULL))
 +		return (EINVAL);
 +
 +	errno = 0;
 +	endptr = NULL;
 +	tmp = (gauge_t) strtod (string, &endptr);
 +	if (errno != 0)
 +		return (errno);
 +	else if ((endptr == NULL) || (*endptr != 0))
 +		return (EINVAL);
 +
 +	*ret_value = tmp;
 +	return (0);
 +} /* }}} int strtogauge */
 +
 +int strarray_add (char ***ret_array, size_t *ret_array_len, char const *str) /* {{{ */
 +{
 +	char **array;
 +	size_t array_len = *ret_array_len;
 +
 +	if (str == NULL)
 +		return (EINVAL);
 +
 +	array = realloc (*ret_array,
 +            (array_len + 1) * sizeof (*array));
 +	if (array == NULL)
 +		return (ENOMEM);
 +	*ret_array = array;
 +
 +	array[array_len] = strdup (str);
 +	if (array[array_len] == NULL)
 +		return (ENOMEM);
 +
 +	array_len++;
 +        *ret_array_len = array_len;
 +	return (0);
 +} /* }}} int strarray_add */
 +
 +void strarray_free (char **array, size_t array_len) /* {{{ */
 +{
 +	size_t i;
 +
 +	for (i = 0; i < array_len; i++)
 +		sfree (array[i]);
 +	sfree (array);
 +} /* }}} void strarray_free */
diff --cc src/daemon/meta_data.c
index 6ee8446b,00000000..4e46ed53
mode 100644,000000..100644
--- a/src/daemon/meta_data.c
+++ b/src/daemon/meta_data.c
@@@ -1,637 -1,0 +1,636 @@@
 +/**
 + * collectd - src/meta_data.c
 + * Copyright (C) 2008-2011  Florian octo Forster
 + *
 + * Permission is hereby granted, free of charge, to any person obtaining a
 + * copy of this software and associated documentation files (the "Software"),
 + * to deal in the Software without restriction, including without limitation
 + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 + * and/or sell copies of the Software, and to permit persons to whom the
 + * Software is furnished to do so, subject to the following conditions:
 + *
 + * The above copyright notice and this permission notice shall be included in
 + * all copies or substantial portions of the Software.
 + *
 + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 + * DEALINGS IN THE SOFTWARE.
 + *
 + * Authors:
 + *   Florian octo Forster <octo at collectd.org>
 + **/
 +
 +#include "collectd.h"
 +#include "plugin.h"
 +#include "meta_data.h"
 +
 +#include <pthread.h>
 +
 +/*
 + * Data types
 + */
 +union meta_value_u
 +{
 +  char    *mv_string;
 +  int64_t  mv_signed_int;
 +  uint64_t mv_unsigned_int;
 +  double   mv_double;
 +  _Bool    mv_boolean;
 +};
 +typedef union meta_value_u meta_value_t;
 +
 +struct meta_entry_s;
 +typedef struct meta_entry_s meta_entry_t;
 +struct meta_entry_s
 +{
 +  char         *key;
 +  meta_value_t  value;
 +  int           type;
 +  meta_entry_t *next;
 +};
 +
 +struct meta_data_s
 +{
 +  meta_entry_t   *head;
 +  pthread_mutex_t lock;
 +};
 +
 +/*
 + * Private functions
 + */
 +static char *md_strdup (const char *orig) /* {{{ */
 +{
 +  size_t sz;
 +  char *dest;
 +
 +  if (orig == NULL)
 +    return (NULL);
 +
 +  sz = strlen (orig) + 1;
 +  dest = (char *) malloc (sz);
 +  if (dest == NULL)
 +    return (NULL);
 +
 +  memcpy (dest, orig, sz);
 +
 +  return (dest);
 +} /* }}} char *md_strdup */
 +
 +static meta_entry_t *md_entry_alloc (const char *key) /* {{{ */
 +{
 +  meta_entry_t *e;
 +
 +  e = (meta_entry_t *) malloc (sizeof (*e));
 +  if (e == NULL)
 +  {
 +    ERROR ("md_entry_alloc: malloc failed.");
 +    return (NULL);
 +  }
 +  memset (e, 0, sizeof (*e));
 +
 +  e->key = md_strdup (key);
 +  if (e->key == NULL)
 +  {
 +    free (e);
 +    ERROR ("md_entry_alloc: md_strdup failed.");
 +    return (NULL);
 +  }
 +
 +  e->type = 0;
 +  e->next = NULL;
 +
 +  return (e);
 +} /* }}} meta_entry_t *md_entry_alloc */
 +
 +static meta_entry_t *md_entry_clone (const meta_entry_t *orig) /* {{{ */
 +{
 +  meta_entry_t *copy;
 +
 +  if (orig == NULL)
 +    return (NULL);
 +
 +  copy = md_entry_alloc (orig->key);
 +  copy->type = orig->type;
 +  if (copy->type == MD_TYPE_STRING)
 +    copy->value.mv_string = strdup (orig->value.mv_string);
 +  else
 +    copy->value = orig->value;
 +
 +  copy->next = md_entry_clone (orig->next);
 +  return (copy);
 +} /* }}} meta_entry_t *md_entry_clone */
 +
 +static void md_entry_free (meta_entry_t *e) /* {{{ */
 +{
 +  if (e == NULL)
 +    return;
 +
 +  free (e->key);
 +
 +  if (e->type == MD_TYPE_STRING)
 +    free (e->value.mv_string);
 +
 +  if (e->next != NULL)
 +    md_entry_free (e->next);
 +
 +  free (e);
 +} /* }}} void md_entry_free */
 +
 +static int md_entry_insert (meta_data_t *md, meta_entry_t *e) /* {{{ */
 +{
 +  meta_entry_t *this;
 +  meta_entry_t *prev;
 +
 +  if ((md == NULL) || (e == NULL))
 +    return (-EINVAL);
 +
 +  pthread_mutex_lock (&md->lock);
 +
 +  prev = NULL;
 +  this = md->head;
 +  while (this != NULL)
 +  {
 +    if (strcasecmp (e->key, this->key) == 0)
 +      break;
 +
 +    prev = this;
 +    this = this->next;
 +  }
 +
 +  if (this == NULL)
 +  {
 +    /* This key does not exist yet. */
 +    if (md->head == NULL)
 +      md->head = e;
 +    else
 +    {
 +      assert (prev != NULL);
 +      prev->next = e;
 +    }
 +
 +    e->next = NULL;
 +  }
 +  else /* (this != NULL) */
 +  {
 +    if (prev == NULL)
 +      md->head = e;
 +    else
 +      prev->next = e;
 +
 +    e->next = this->next;
 +  }
 +
 +  pthread_mutex_unlock (&md->lock);
 +
 +  if (this != NULL)
 +  {
 +    this->next = NULL;
 +    md_entry_free (this);
 +  }
 +
 +  return (0);
 +} /* }}} int md_entry_insert */
 +
 +/* XXX: The lock on md must be held while calling this function! */
 +static meta_entry_t *md_entry_lookup (meta_data_t *md, /* {{{ */
 +    const char *key)
 +{
 +  meta_entry_t *e;
 +
 +  if ((md == NULL) || (key == NULL))
 +    return (NULL);
 +
 +  for (e = md->head; e != NULL; e = e->next)
 +    if (strcasecmp (key, e->key) == 0)
 +      break;
 +
 +  return (e);
 +} /* }}} meta_entry_t *md_entry_lookup */
 +
 +/*
 + * Public functions
 + */
 +meta_data_t *meta_data_create (void) /* {{{ */
 +{
 +  meta_data_t *md;
 +
 +  md = (meta_data_t *) malloc (sizeof (*md));
 +  if (md == NULL)
 +  {
 +    ERROR ("meta_data_create: malloc failed.");
 +    return (NULL);
 +  }
 +  memset (md, 0, sizeof (*md));
 +
 +  md->head = NULL;
 +  pthread_mutex_init (&md->lock, /* attr = */ NULL);
 +
 +  return (md);
 +} /* }}} meta_data_t *meta_data_create */
 +
 +meta_data_t *meta_data_clone (meta_data_t *orig) /* {{{ */
 +{
 +  meta_data_t *copy;
 +
 +  if (orig == NULL)
 +    return (NULL);
 +
 +  copy = meta_data_create ();
 +  if (copy == NULL)
 +    return (NULL);
 +
 +  pthread_mutex_lock (&orig->lock);
 +  copy->head = md_entry_clone (orig->head);
 +  pthread_mutex_unlock (&orig->lock);
 +
 +  return (copy);
 +} /* }}} meta_data_t *meta_data_clone */
 +
 +void meta_data_destroy (meta_data_t *md) /* {{{ */
 +{
 +  if (md == NULL)
 +    return;
 +
-   pthread_mutex_destroy(&md->lock);
 +  md_entry_free (md->head);
 +  pthread_mutex_destroy (&md->lock);
 +  free (md);
 +} /* }}} void meta_data_destroy */
 +
 +int meta_data_exists (meta_data_t *md, const char *key) /* {{{ */
 +{
 +  meta_entry_t *e;
 +
 +  if ((md == NULL) || (key == NULL))
 +    return (-EINVAL);
 +
 +  pthread_mutex_lock (&md->lock);
 +
 +  for (e = md->head; e != NULL; e = e->next)
 +  {
 +    if (strcasecmp (key, e->key) == 0)
 +    {
 +      pthread_mutex_unlock (&md->lock);
 +      return (1);
 +    }
 +  }
 +
 +  pthread_mutex_unlock (&md->lock);
 +  return (0);
 +} /* }}} int meta_data_exists */
 +
 +int meta_data_type (meta_data_t *md, const char *key) /* {{{ */
 +{
 +  meta_entry_t *e;
 +
 +  if ((md == NULL) || (key == NULL))
 +    return -EINVAL;
 +
 +  pthread_mutex_lock (&md->lock);
 +
 +  for (e = md->head; e != NULL; e = e->next)
 +  {
 +    if (strcasecmp (key, e->key) == 0)
 +    {
 +      pthread_mutex_unlock (&md->lock);
 +      return e->type;
 +    }
 +  }
 +
 +  pthread_mutex_unlock (&md->lock);
 +  return 0;
 +} /* }}} int meta_data_type */
 +
 +int meta_data_toc (meta_data_t *md, char ***toc) /* {{{ */
 +{
 +  int i = 0, count = 0;
 +  meta_entry_t *e;
 +
 +  if ((md == NULL) || (toc == NULL))
 +    return -EINVAL;
 +
 +  pthread_mutex_lock (&md->lock);
 +
 +  for (e = md->head; e != NULL; e = e->next)
 +    ++count;    
 +
 +  if (count == 0)
 +  {
 +    pthread_mutex_unlock (&md->lock);
 +    return (count);
 +  }
 +
 +  *toc = calloc(count, sizeof(**toc));
 +  for (e = md->head; e != NULL; e = e->next)
 +    (*toc)[i++] = strdup(e->key);
 +  
 +  pthread_mutex_unlock (&md->lock);
 +  return count;
 +} /* }}} int meta_data_toc */
 +
 +int meta_data_delete (meta_data_t *md, const char *key) /* {{{ */
 +{
 +  meta_entry_t *this;
 +  meta_entry_t *prev;
 +
 +  if ((md == NULL) || (key == NULL))
 +    return (-EINVAL);
 +
 +  pthread_mutex_lock (&md->lock);
 +
 +  prev = NULL;
 +  this = md->head;
 +  while (this != NULL)
 +  {
 +    if (strcasecmp (key, this->key) == 0)
 +      break;
 +
 +    prev = this;
 +    this = this->next;
 +  }
 +
 +  if (this == NULL)
 +  {
 +    pthread_mutex_unlock (&md->lock);
 +    return (-ENOENT);
 +  }
 +
 +  if (prev == NULL)
 +    md->head = this->next;
 +  else
 +    prev->next = this->next;
 +
 +  pthread_mutex_unlock (&md->lock);
 +
 +  this->next = NULL;
 +  md_entry_free (this);
 +
 +  return (0);
 +} /* }}} int meta_data_delete */
 +
 +/*
 + * Add functions
 + */
 +int meta_data_add_string (meta_data_t *md, /* {{{ */
 +    const char *key, const char *value)
 +{
 +  meta_entry_t *e;
 +
 +  if ((md == NULL) || (key == NULL) || (value == NULL))
 +    return (-EINVAL);
 +
 +  e = md_entry_alloc (key);
 +  if (e == NULL)
 +    return (-ENOMEM);
 +
 +  e->value.mv_string = md_strdup (value);
 +  if (e->value.mv_string == NULL)
 +  {
 +    ERROR ("meta_data_add_string: md_strdup failed.");
 +    md_entry_free (e);
 +    return (-ENOMEM);
 +  }
 +  e->type = MD_TYPE_STRING;
 +
 +  return (md_entry_insert (md, e));
 +} /* }}} int meta_data_add_string */
 +
 +int meta_data_add_signed_int (meta_data_t *md, /* {{{ */
 +    const char *key, int64_t value)
 +{
 +  meta_entry_t *e;
 +
 +  if ((md == NULL) || (key == NULL))
 +    return (-EINVAL);
 +
 +  e = md_entry_alloc (key);
 +  if (e == NULL)
 +    return (-ENOMEM);
 +
 +  e->value.mv_signed_int = value;
 +  e->type = MD_TYPE_SIGNED_INT;
 +
 +  return (md_entry_insert (md, e));
 +} /* }}} int meta_data_add_signed_int */
 +
 +int meta_data_add_unsigned_int (meta_data_t *md, /* {{{ */
 +    const char *key, uint64_t value)
 +{
 +  meta_entry_t *e;
 +
 +  if ((md == NULL) || (key == NULL))
 +    return (-EINVAL);
 +
 +  e = md_entry_alloc (key);
 +  if (e == NULL)
 +    return (-ENOMEM);
 +
 +  e->value.mv_unsigned_int = value;
 +  e->type = MD_TYPE_UNSIGNED_INT;
 +
 +  return (md_entry_insert (md, e));
 +} /* }}} int meta_data_add_unsigned_int */
 +
 +int meta_data_add_double (meta_data_t *md, /* {{{ */
 +    const char *key, double value)
 +{
 +  meta_entry_t *e;
 +
 +  if ((md == NULL) || (key == NULL))
 +    return (-EINVAL);
 +
 +  e = md_entry_alloc (key);
 +  if (e == NULL)
 +    return (-ENOMEM);
 +
 +  e->value.mv_double = value;
 +  e->type = MD_TYPE_DOUBLE;
 +
 +  return (md_entry_insert (md, e));
 +} /* }}} int meta_data_add_double */
 +
 +int meta_data_add_boolean (meta_data_t *md, /* {{{ */
 +    const char *key, _Bool value)
 +{
 +  meta_entry_t *e;
 +
 +  if ((md == NULL) || (key == NULL))
 +    return (-EINVAL);
 +
 +  e = md_entry_alloc (key);
 +  if (e == NULL)
 +    return (-ENOMEM);
 +
 +  e->value.mv_boolean = value;
 +  e->type = MD_TYPE_BOOLEAN;
 +
 +  return (md_entry_insert (md, e));
 +} /* }}} int meta_data_add_boolean */
 +
 +/*
 + * Get functions
 + */
 +int meta_data_get_string (meta_data_t *md, /* {{{ */
 +    const char *key, char **value)
 +{
 +  meta_entry_t *e;
 +  char *temp;
 +
 +  if ((md == NULL) || (key == NULL) || (value == NULL))
 +    return (-EINVAL);
 +
 +  pthread_mutex_lock (&md->lock);
 +
 +  e = md_entry_lookup (md, key);
 +  if (e == NULL)
 +  {
 +    pthread_mutex_unlock (&md->lock);
 +    return (-ENOENT);
 +  }
 +
 +  if (e->type != MD_TYPE_STRING)
 +  {
 +    ERROR ("meta_data_get_string: Type mismatch for key `%s'", e->key);
 +    pthread_mutex_unlock (&md->lock);
 +    return (-ENOENT);
 +  }
 +
 +  temp = md_strdup (e->value.mv_string);
 +  if (temp == NULL)
 +  {
 +    pthread_mutex_unlock (&md->lock);
 +    ERROR ("meta_data_get_string: md_strdup failed.");
 +    return (-ENOMEM);
 +  }
 + 
 +  pthread_mutex_unlock (&md->lock);
 +
 +  *value = temp;
 +
 +  return (0);
 +} /* }}} int meta_data_get_string */
 +
 +int meta_data_get_signed_int (meta_data_t *md, /* {{{ */
 +    const char *key, int64_t *value)
 +{
 +  meta_entry_t *e;
 +
 +  if ((md == NULL) || (key == NULL) || (value == NULL))
 +    return (-EINVAL);
 +
 +  pthread_mutex_lock (&md->lock);
 +
 +  e = md_entry_lookup (md, key);
 +  if (e == NULL)
 +  {
 +    pthread_mutex_unlock (&md->lock);
 +    return (-ENOENT);
 +  }
 +
 +  if (e->type != MD_TYPE_SIGNED_INT)
 +  {
 +    ERROR ("meta_data_get_signed_int: Type mismatch for key `%s'", e->key);
 +    pthread_mutex_unlock (&md->lock);
 +    return (-ENOENT);
 +  }
 +
 +  *value = e->value.mv_signed_int;
 +
 +  pthread_mutex_unlock (&md->lock);
 +  return (0);
 +} /* }}} int meta_data_get_signed_int */
 +
 +int meta_data_get_unsigned_int (meta_data_t *md, /* {{{ */
 +    const char *key, uint64_t *value)
 +{
 +  meta_entry_t *e;
 +
 +  if ((md == NULL) || (key == NULL) || (value == NULL))
 +    return (-EINVAL);
 +
 +  pthread_mutex_lock (&md->lock);
 +
 +  e = md_entry_lookup (md, key);
 +  if (e == NULL)
 +  {
 +    pthread_mutex_unlock (&md->lock);
 +    return (-ENOENT);
 +  }
 +
 +  if (e->type != MD_TYPE_UNSIGNED_INT)
 +  {
 +    ERROR ("meta_data_get_unsigned_int: Type mismatch for key `%s'", e->key);
 +    pthread_mutex_unlock (&md->lock);
 +    return (-ENOENT);
 +  }
 +
 +  *value = e->value.mv_unsigned_int;
 +
 +  pthread_mutex_unlock (&md->lock);
 +  return (0);
 +} /* }}} int meta_data_get_unsigned_int */
 +
 +int meta_data_get_double (meta_data_t *md, /* {{{ */
 +    const char *key, double *value)
 +{
 +  meta_entry_t *e;
 +
 +  if ((md == NULL) || (key == NULL) || (value == NULL))
 +    return (-EINVAL);
 +
 +  pthread_mutex_lock (&md->lock);
 +
 +  e = md_entry_lookup (md, key);
 +  if (e == NULL)
 +  {
 +    pthread_mutex_unlock (&md->lock);
 +    return (-ENOENT);
 +  }
 +
 +  if (e->type != MD_TYPE_DOUBLE)
 +  {
 +    ERROR ("meta_data_get_double: Type mismatch for key `%s'", e->key);
 +    pthread_mutex_unlock (&md->lock);
 +    return (-ENOENT);
 +  }
 +
 +  *value = e->value.mv_double;
 +
 +  pthread_mutex_unlock (&md->lock);
 +  return (0);
 +} /* }}} int meta_data_get_double */
 +
 +int meta_data_get_boolean (meta_data_t *md, /* {{{ */
 +    const char *key, _Bool *value)
 +{
 +  meta_entry_t *e;
 +
 +  if ((md == NULL) || (key == NULL) || (value == NULL))
 +    return (-EINVAL);
 +
 +  pthread_mutex_lock (&md->lock);
 +
 +  e = md_entry_lookup (md, key);
 +  if (e == NULL)
 +  {
 +    pthread_mutex_unlock (&md->lock);
 +    return (-ENOENT);
 +  }
 +
 +  if (e->type != MD_TYPE_BOOLEAN)
 +  {
 +    ERROR ("meta_data_get_boolean: Type mismatch for key `%s'", e->key);
 +    pthread_mutex_unlock (&md->lock);
 +    return (-ENOENT);
 +  }
 +
 +  *value = e->value.mv_boolean;
 +
 +  pthread_mutex_unlock (&md->lock);
 +  return (0);
 +} /* }}} int meta_data_get_boolean */
 +
 +/* vim: set sw=2 sts=2 et fdm=marker : */
diff --cc src/daemon/utils_avltree.c
index e251975b,00000000..58b8b847
mode 100644,000000..100644
--- a/src/daemon/utils_avltree.c
+++ b/src/daemon/utils_avltree.c
@@@ -1,744 -1,0 +1,745 @@@
 +/**
 + * collectd - src/utils_avltree.c
 + * Copyright (C) 2006,2007  Florian octo Forster
 + *
 + * Permission is hereby granted, free of charge, to any person obtaining a
 + * copy of this software and associated documentation files (the "Software"),
 + * to deal in the Software without restriction, including without limitation
 + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 + * and/or sell copies of the Software, and to permit persons to whom the
 + * Software is furnished to do so, subject to the following conditions:
 + *
 + * The above copyright notice and this permission notice shall be included in
 + * all copies or substantial portions of the Software.
 + *
 + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 + * DEALINGS IN THE SOFTWARE.
 + *
 + * Authors:
 + *   Florian octo Forster <octo at collectd.org>
 + **/
 +
 +#include "config.h"
 +
 +#include <stdlib.h>
 +#include <stdio.h>
 +#include <string.h>
 +#include <assert.h>
 +
 +#include "utils_avltree.h"
 +
 +#define BALANCE(n) ((((n)->left == NULL) ? 0 : (n)->left->height) \
 +		- (((n)->right == NULL) ? 0 : (n)->right->height))
 +
 +/*
 + * private data types
 + */
 +struct c_avl_node_s
 +{
 +	void *key;
 +	void *value;
 +
 +	int height;
 +	struct c_avl_node_s *left;
 +	struct c_avl_node_s *right;
 +	struct c_avl_node_s *parent;
 +};
 +typedef struct c_avl_node_s c_avl_node_t;
 +
 +struct c_avl_tree_s
 +{
 +	c_avl_node_t *root;
 +	int (*compare) (const void *, const void *);
 +	int size;
 +};
 +
 +struct c_avl_iterator_s
 +{
 +	c_avl_tree_t *tree;
 +	c_avl_node_t *node;
 +};
 +
 +/*
 + * private functions
 + */
 +#if 0
 +static void verify_tree (c_avl_node_t *n)
 +{
 +	if (n == NULL)
 +		return;
 +
 +	verify_tree (n->left);
 +	verify_tree (n->right);
 +
 +	assert ((BALANCE (n) >= -1) && (BALANCE (n) <= 1));
 +	assert ((n->parent == NULL) || (n->parent->right == n) || (n->parent->left == n));
 +} /* void verify_tree */
 +#else
 +# define verify_tree(n) /**/
 +#endif
 +
 +static void free_node (c_avl_node_t *n)
 +{
 +	if (n == NULL)
 +		return;
 +
 +	if (n->left != NULL)
 +		free_node (n->left);
 +	if (n->right != NULL)
 +		free_node (n->right);
 +
 +	free (n);
 +}
 +
 +static int calc_height (c_avl_node_t *n)
 +{
 +	int height_left;
 +	int height_right;
 +
 +	if (n == NULL)
 +		return (0);
 +
 +	height_left  = (n->left == NULL)  ? 0 : n->left->height;
 +	height_right = (n->right == NULL) ? 0 : n->right->height;
 +
 +	return (((height_left > height_right)
 +				? height_left
 +				: height_right) + 1);
 +} /* int calc_height */
 +
 +static c_avl_node_t *search (c_avl_tree_t *t, const void *key)
 +{
 +	c_avl_node_t *n;
 +	int cmp;
 +
 +	n = t->root;
 +	while (n != NULL)
 +	{
 +		cmp = t->compare (key, n->key);
 +		if (cmp == 0)
 +			return (n);
 +		else if (cmp < 0)
 +			n = n->left;
 +		else
 +			n = n->right;
 +	}
 +
 +	return (NULL);
 +}
 +
 +/*         (x)             (y)
 + *        /   \           /   \
 + *     (y)    /\         /\    (x)
 + *    /   \  /_c\  ==>  / a\  /   \
 + *   /\   /\           /____\/\   /\
 + *  / a\ /_b\               /_b\ /_c\
 + * /____\
 + */
 +static c_avl_node_t *rotate_right (c_avl_tree_t *t, c_avl_node_t *x)
 +{
 +	c_avl_node_t *p;
 +	c_avl_node_t *y;
 +	c_avl_node_t *b;
 +
 +	assert (x != NULL);
 +	assert (x->left != NULL);
 +
 +	p = x->parent;
 +	y = x->left;
 +	b = y->right;
 +
 +	x->left = b;
 +	if (b != NULL)
 +		b->parent = x;
 +
 +	x->parent = y;
 +	y->right = x;
 +
 +	y->parent = p;
 +	assert ((p == NULL) || (p->left == x) || (p->right == x));
 +	if (p == NULL)
 +		t->root = y;
 +	else if (p->left == x)
 +		p->left = y;
 +	else
 +		p->right = y;
 +
 +	x->height = calc_height (x);
 +	y->height = calc_height (y);
 +
 +	return (y);
 +} /* void rotate_right */
 +
 +/*
 + *    (x)                   (y)
 + *   /   \                 /   \
 + *  /\    (y)           (x)    /\
 + * /_a\  /   \   ==>   /   \  / c\
 + *      /\   /\       /\   /\/____\
 + *     /_b\ / c\     /_a\ /_b\
 + *         /____\
 + */
 +static c_avl_node_t *rotate_left (c_avl_tree_t *t, c_avl_node_t *x)
 +{
 +	c_avl_node_t *p;
 +	c_avl_node_t *y;
 +	c_avl_node_t *b;
 +
 +	assert (x != NULL);
 +	assert (x->right != NULL);
 +
 +	p = x->parent;
 +	y = x->right;
 +	b = y->left;
 +
 +	x->right = b;
 +	if (b != NULL)
 +		b->parent = x;
 +
 +	x->parent = y;
 +	y->left = x;
 +
 +	y->parent = p;
 +	assert ((p == NULL) || (p->left == x) || (p->right == x));
 +	if (p == NULL)
 +		t->root = y;
 +	else if (p->left == x)
 +		p->left = y;
 +	else
 +		p->right = y;
 +
 +	x->height = calc_height (x);
 +	y->height = calc_height (y);
 +
 +	return (y);
 +} /* void rotate_left */
 +
 +static c_avl_node_t *rotate_left_right (c_avl_tree_t *t, c_avl_node_t *x)
 +{
 +	rotate_left (t, x->left);
 +	return (rotate_right (t, x));
 +} /* void rotate_left_right */
 +
 +static c_avl_node_t *rotate_right_left (c_avl_tree_t *t, c_avl_node_t *x)
 +{
 +	rotate_right (t, x->right);
 +	return (rotate_left (t, x));
 +} /* void rotate_right_left */
 +
 +static void rebalance (c_avl_tree_t *t, c_avl_node_t *n)
 +{
 +	int b_top;
 +	int b_bottom;
 +
 +	while (n != NULL)
 +	{
 +		b_top = BALANCE (n);
 +		assert ((b_top >= -2) && (b_top <= 2));
 +
 +		if (b_top == -2)
 +		{
 +			assert (n->right != NULL);
 +			b_bottom = BALANCE (n->right);
 +			assert ((b_bottom >= -1) || (b_bottom <= 1));
 +			if (b_bottom == 1)
 +				n = rotate_right_left (t, n);
 +			else
 +				n = rotate_left (t, n);
 +		}
 +		else if (b_top == 2)
 +		{
 +			assert (n->left != NULL);
 +			b_bottom = BALANCE (n->left);
 +			assert ((b_bottom >= -1) || (b_bottom <= 1));
 +			if (b_bottom == -1)
 +				n = rotate_left_right (t, n);
 +			else
 +				n = rotate_right (t, n);
 +		}
 +		else
 +		{
 +			int height = calc_height (n);
 +			if (height == n->height)
 +				break;
 +			n->height = height;
 +		}
 +
 +		assert (n->height == calc_height (n));
 +
 +		n = n->parent;
 +	} /* while (n != NULL) */
 +} /* void rebalance */
 +
 +static c_avl_node_t *c_avl_node_next (c_avl_node_t *n)
 +{
 +	c_avl_node_t *r; /* return node */
 +
 +	if (n == NULL)
 +	{
 +		return (NULL);
 +	}
 +
 +	/* If we can't descent any further, we have to backtrack to the first
 +	 * parent that's bigger than we, i. e. who's _left_ child we are. */
 +	if (n->right == NULL)
 +	{
 +		r = n->parent;
 +		while ((r != NULL) && (r->parent != NULL))
 +		{
 +			if (r->left == n)
 +				break;
 +			n = r;
 +			r = n->parent;
 +		}
 +
 +		/* n->right == NULL && r == NULL => t is root and has no next
 +		 * r->left != n => r->right = n => r->parent == NULL */
 +		if ((r == NULL) || (r->left != n))
 +		{
 +			assert ((r == NULL) || (r->parent == NULL));
 +			return (NULL);
 +		}
 +		else
 +		{
 +			assert (r->left == n);
 +			return (r);
 +		}
 +	}
 +	else
 +	{
 +		r = n->right;
 +		while (r->left != NULL)
 +			r = r->left;
 +	}
 +
 +	return (r);
 +} /* c_avl_node_t *c_avl_node_next */
 +
 +static c_avl_node_t *c_avl_node_prev (c_avl_node_t *n)
 +{
 +	c_avl_node_t *r; /* return node */
 +
 +	if (n == NULL)
 +	{
 +		return (NULL);
 +	}
 +
 +	/* If we can't descent any further, we have to backtrack to the first
 +	 * parent that's smaller than we, i. e. who's _right_ child we are. */
 +	if (n->left == NULL)
 +	{
 +		r = n->parent;
 +		while ((r != NULL) && (r->parent != NULL))
 +		{
 +			if (r->right == n)
 +				break;
 +			n = r;
 +			r = n->parent;
 +		}
 +
 +		/* n->left == NULL && r == NULL => t is root and has no next
 +		 * r->right != n => r->left = n => r->parent == NULL */
 +		if ((r == NULL) || (r->right != n))
 +		{
 +			assert ((r == NULL) || (r->parent == NULL));
 +			return (NULL);
 +		}
 +		else
 +		{
 +			assert (r->right == n);
 +			return (r);
 +		}
 +	}
 +	else
 +	{
 +		r = n->left;
 +		while (r->right != NULL)
 +			r = r->right;
 +	}
 +
 +	return (r);
 +} /* c_avl_node_t *c_avl_node_prev */
 +
 +static int _remove (c_avl_tree_t *t, c_avl_node_t *n)
 +{
 +	assert ((t != NULL) && (n != NULL));
 +
 +	if ((n->left != NULL) && (n->right != NULL))
 +	{
 +		c_avl_node_t *r; /* replacement node */
 +		if (BALANCE (n) > 0) /* left subtree is higher */
 +		{
 +			assert (n->left != NULL);
 +			r = c_avl_node_prev (n);
 +			
 +		}
 +		else /* right subtree is higher */
 +		{
 +			assert (n->right != NULL);
 +			r = c_avl_node_next (n);
 +		}
 +
 +		assert ((r->left == NULL) || (r->right == NULL));
 +
 +		/* copy content */
 +		n->key   = r->key;
 +		n->value = r->value;
 +
 +		n = r;
 +	}
 +
 +	assert ((n->left == NULL) || (n->right == NULL));
 +
 +	if ((n->left == NULL) && (n->right == NULL))
 +	{
 +		/* Deleting a leave is easy */
 +		if (n->parent == NULL)
 +		{
 +			assert (t->root == n);
 +			t->root = NULL;
 +		}
 +		else
 +		{
 +			assert ((n->parent->left == n)
 +					|| (n->parent->right == n));
 +			if (n->parent->left == n)
 +				n->parent->left = NULL;
 +			else
 +				n->parent->right = NULL;
 +
 +			rebalance (t, n->parent);
 +		}
 +
 +		free_node (n);
 +	}
 +	else if (n->left == NULL)
 +	{
 +		assert (BALANCE (n) == -1);
 +		assert ((n->parent == NULL) || (n->parent->left == n) || (n->parent->right == n));
 +		if (n->parent == NULL)
 +		{
 +			assert (t->root == n);
 +			t->root = n->right;
 +		}
 +		else if (n->parent->left == n)
 +		{
 +			n->parent->left = n->right;
 +		}
 +		else
 +		{
 +			n->parent->right = n->right;
 +		}
 +		n->right->parent = n->parent;
 +
 +		if (n->parent != NULL)
 +			rebalance (t, n->parent);
 +
 +		n->right = NULL;
 +		free_node (n);
 +	}
 +	else if (n->right == NULL)
 +	{
 +		assert (BALANCE (n) == 1);
 +		assert ((n->parent == NULL) || (n->parent->left == n) || (n->parent->right == n));
 +		if (n->parent == NULL)
 +		{
 +			assert (t->root == n);
 +			t->root = n->left;
 +		}
 +		else if (n->parent->left == n)
 +		{
 +			n->parent->left = n->left;
 +		}
 +		else
 +		{
 +			n->parent->right = n->left;
 +		}
 +		n->left->parent = n->parent;
 +
 +		if (n->parent != NULL)
 +			rebalance (t, n->parent);
 +
 +		n->left = NULL;
 +		free_node (n);
 +	}
 +	else
 +	{
 +		assert (0);
 +	}
 +
 +	return (0);
 +} /* void *_remove */
 +
 +/*
 + * public functions
 + */
 +c_avl_tree_t *c_avl_create (int (*compare) (const void *, const void *))
 +{
 +	c_avl_tree_t *t;
 +
 +	if (compare == NULL)
 +		return (NULL);
 +
 +	if ((t = (c_avl_tree_t *) malloc (sizeof (c_avl_tree_t))) == NULL)
 +		return (NULL);
 +
 +	t->root = NULL;
 +	t->compare = compare;
 +	t->size = 0;
 +
 +	return (t);
 +}
 +
 +void c_avl_destroy (c_avl_tree_t *t)
 +{
 +	if (t == NULL)
 +		return;
 +	free_node (t->root);
 +	free (t);
 +}
 +
 +int c_avl_insert (c_avl_tree_t *t, void *key, void *value)
 +{
 +	c_avl_node_t *new;
 +	c_avl_node_t *nptr;
 +	int cmp;
 +
 +	if ((new = (c_avl_node_t *) malloc (sizeof (c_avl_node_t))) == NULL)
 +		return (-1);
 +
 +	new->key = key;
 +	new->value = value;
 +	new->height = 1;
 +	new->left = NULL;
 +	new->right = NULL;
 +
 +	if (t->root == NULL)
 +	{
 +		new->parent = NULL;
 +		t->root = new;
 +		t->size = 1;
 +		return (0);
 +	}
 +
 +	nptr = t->root;
 +	while (42)
 +	{
 +		cmp = t->compare (nptr->key, new->key);
 +		if (cmp == 0)
 +		{
 +			free_node (new);
 +			return (1);
 +		}
 +		else if (cmp < 0)
 +		{
 +			/* nptr < new */
 +			if (nptr->right == NULL)
 +			{
 +				nptr->right = new;
 +				new->parent = nptr;
 +				rebalance (t, nptr);
 +				break;
 +			}
 +			else
 +			{
 +				nptr = nptr->right;
 +			}
 +		}
 +		else /* if (cmp > 0) */
 +		{
 +			/* nptr > new */
 +			if (nptr->left == NULL)
 +			{
 +				nptr->left = new;
 +				new->parent = nptr;
 +				rebalance (t, nptr);
 +				break;
 +			}
 +			else
 +			{
 +				nptr = nptr->left;
 +			}
 +		}
 +	} /* while (42) */
 +
 +	verify_tree (t->root);
 +	++t->size;
 +	return (0);
 +} /* int c_avl_insert */
 +
 +int c_avl_remove (c_avl_tree_t *t, const void *key, void **rkey, void **rvalue)
 +{
 +	c_avl_node_t *n;
 +	int status;
 +
 +	assert (t != NULL);
 +
 +	n = search (t, key);
 +	if (n == NULL)
 +		return (-1);
 +
 +	if (rkey != NULL)
 +		*rkey = n->key;
 +	if (rvalue != NULL)
 +		*rvalue = n->value;
 +
 +	status = _remove (t, n);
 +	verify_tree (t->root);
 +	--t->size;
 +	return (status);
 +} /* void *c_avl_remove */
 +
 +int c_avl_get (c_avl_tree_t *t, const void *key, void **value)
 +{
 +	c_avl_node_t *n;
 +
 +	assert (t != NULL);
 +
 +	n = search (t, key);
 +	if (n == NULL)
 +		return (-1);
 +
 +	if (value != NULL)
 +		*value = n->value;
 +
 +	return (0);
 +}
 +
 +int c_avl_pick (c_avl_tree_t *t, void **key, void **value)
 +{
 +	c_avl_node_t *n;
 +	c_avl_node_t *p;
 +
 +	if ((key == NULL) || (value == NULL))
 +		return (-1);
 +	if (t->root == NULL)
 +		return (-1);
 +
 +	n = t->root;
 +	while ((n->left != NULL) || (n->right != NULL))
 +	{
 +		if (n->left == NULL)
 +		{
 +			n = n->right;
 +			continue;
 +		}
 +		else if (n->right == NULL)
 +		{
 +			n = n->left;
 +			continue;
 +		}
 +
 +		if (n->left->height > n->right->height)
 +			n = n->left;
 +		else
 +			n = n->right;
 +	}
 +
 +	p = n->parent;
 +	if (p == NULL)
 +		t->root = NULL;
 +	else if (p->left == n)
 +		p->left = NULL;
 +	else
 +		p->right = NULL;
 +
 +	*key   = n->key;
 +	*value = n->value;
 +
 +	free_node (n);
++	--t->size;
 +	rebalance (t, p);
 +
 +	return (0);
 +} /* int c_avl_pick */
 +
 +c_avl_iterator_t *c_avl_get_iterator (c_avl_tree_t *t)
 +{
 +	c_avl_iterator_t *iter;
 +
 +	if (t == NULL)
 +		return (NULL);
 +
 +	iter = (c_avl_iterator_t *) malloc (sizeof (c_avl_iterator_t));
 +	if (iter == NULL)
 +		return (NULL);
 +	memset (iter, '\0', sizeof (c_avl_iterator_t));
 +	iter->tree = t;
 +
 +	return (iter);
 +} /* c_avl_iterator_t *c_avl_get_iterator */
 +
 +int c_avl_iterator_next (c_avl_iterator_t *iter, void **key, void **value)
 +{
 +	c_avl_node_t *n;
 +
 +	if ((iter == NULL) || (key == NULL) || (value == NULL))
 +		return (-1);
 +
 +	if (iter->node == NULL)
 +	{
 +		for (n = iter->tree->root; n != NULL; n = n->left)
 +			if (n->left == NULL)
 +				break;
 +		iter->node = n;
 +	}
 +	else
 +	{
 +		n = c_avl_node_next (iter->node);
 +	}
 +
 +	if (n == NULL)
 +		return (-1);
 +
 +	iter->node = n;
 +	*key = n->key;
 +	*value = n->value;
 +
 +	return (0);
 +} /* int c_avl_iterator_next */
 +
 +int c_avl_iterator_prev (c_avl_iterator_t *iter, void **key, void **value)
 +{
 +	c_avl_node_t *n;
 +
 +	if ((iter == NULL) || (key == NULL) || (value == NULL))
 +		return (-1);
 +
 +	if (iter->node == NULL)
 +	{
 +		for (n = iter->tree->root; n != NULL; n = n->left)
 +			if (n->right == NULL)
 +				break;
 +		iter->node = n;
 +	}
 +	else
 +	{
 +		n = c_avl_node_prev (iter->node);
 +	}
 +
 +	if (n == NULL)
 +		return (-1);
 +
 +	iter->node = n;
 +	*key = n->key;
 +	*value = n->value;
 +
 +	return (0);
 +} /* int c_avl_iterator_prev */
 +
 +void c_avl_iterator_destroy (c_avl_iterator_t *iter)
 +{
 +	free (iter);
 +}
 +
 +int c_avl_size (c_avl_tree_t *t)
 +{
 +	if (t == NULL)
 +		return (0);
 +	return (t->size);
 +}