initial commit

.gitignore

@@ -0,0 +1,4 @@
+*.d
+*.o
+ctstats
+ctstats.log

Makefile

@@ -0,0 +1,21 @@
+CFLAGS := -O2 -pipe -Wall
+LDFLAGS := -lpthread -lnfnetlink -lnetfilter_conntrack
+
+OBJS := configfile.o conntrack.o database.o hashtable.o logging.o ctstats.o
+
+all: ctstats
+
+ctstats: $(OBJS)
+	$(CC) $(CFLAGS) $(LDFLAGS) $^ -o $@
+
+%.o: %.c
+	$(CC) $(CFLAGS) -c $< -o $@
+
+%.d: %.c
+	$(CC) $(CFLAGS) -MM -c $< -o $@
+
+clean:
+	rm -f ctstats *.d *.o *.log
+
+DEPS := $(wildcard *.c)
+-include $(DEPS:.c=.d)

configfile.c

@@ -0,0 +1,200 @@
+/***************************************************************************
+ *   Copyright (C) 06/2006 by Olaf Rempel                                  *
+ *   razzor@kopf-tisch.de                                                  *
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ *   This program is distributed in the hope that it will be useful,       *
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
+ *   GNU General Public License for more details.                          *
+ *                                                                         *
+ *   You should have received a copy of the GNU General Public License     *
+ *   along with this program; if not, write to the                         *
+ *   Free Software Foundation, Inc.,                                       *
+ *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
+ ***************************************************************************/
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netinet/ip.h>
+#include <arpa/inet.h>
+
+#include "configfile.h"
+#include "list.h"
+#include "logging.h"
+
+#define BUFSIZE 1024
+
+struct conf_section {
+	struct list_head list;
+	struct list_head tupel_list;
+	char *name;
+};
+
+struct conf_tupel {
+	struct list_head list;
+	char *option;
+	char *parameter;
+};
+
+static LIST_HEAD(config_list);
+
+static struct conf_section * config_add_section(const char *name)
+{
+	struct conf_section *section;
+	section = malloc(sizeof(struct conf_section) + strlen(name));
+	if (section == NULL)
+		return NULL;
+
+	INIT_LIST_HEAD(&section->list);
+	INIT_LIST_HEAD(&section->tupel_list);
+
+	section->name = strdup(name);
+	if (section->name == NULL) {
+		free(section);
+		return NULL;
+	}
+
+	list_add_tail(&section->list, &config_list);
+	return section;
+}
+
+static int config_add_tupel(struct conf_section *section, const char *option, const char *parameter)
+{
+	struct conf_tupel *tupel = malloc(sizeof(struct conf_tupel));
+	if (tupel == NULL)
+		return -1;
+
+	INIT_LIST_HEAD(&tupel->list);
+	tupel->option = strdup(option);
+	tupel->parameter = strdup(parameter);
+
+	if (tupel->option == NULL || tupel->parameter == NULL) {
+		free(tupel);
+		return -1;
+	}
+
+	list_add_tail(&tupel->list, &section->tupel_list);
+	return 0;
+}
+
+int config_parse(const char *config)
+{
+	FILE *fz = fopen(config, "r");
+	if (fz == NULL) {
+		log_print(LOG_ERROR, "config_parse(): %s", config);
+		return -1;
+	}
+
+	char *line = malloc(BUFSIZE);
+	if (line == NULL) {
+		log_print(LOG_ERROR, "config_parse(): out of memory");
+		fclose(fz);
+		return -1;
+	}
+
+	int linenum = 0;
+	struct conf_section *section = NULL;
+	while (fgets(line, BUFSIZE, fz) != NULL) {
+		linenum++;
+
+		if (line[0] == '#' || line[0] <= ' ') {
+			continue;
+
+		} else if (line[0] == '[') {
+			char *tok = strtok(line +1, " ]\n");
+
+			if (tok == NULL || (section = config_add_section(tok)) == NULL) {
+				log_print(LOG_WARN, "config_parse(): invalid section in row %d", linenum);
+				free(line);
+				fclose(fz);
+				return -1;
+			}
+			continue;
+
+		} else if (section == NULL) {
+			log_print(LOG_WARN, "config_parse(): missing section in row %d", linenum);
+			free(line);
+			fclose(fz);
+			return -1;
+		}
+
+		char *tok = strtok(line, " \n");
+		if (tok != NULL) {
+			char *tok2;
+			while ((tok2 = strtok(NULL, " \n"))) {
+				if (config_add_tupel(section, tok, tok2) != 0)
+					log_print(LOG_WARN, "config_parse(): invalid row %d", linenum);
+			}
+		}
+	}
+
+	fclose(fz);
+	free(line);
+	return 0;
+}
+
+static struct conf_section * config_get_section(const char *name)
+{
+	struct conf_section *section;
+
+	list_for_each_entry(section, &config_list, list) {
+		if (!strcmp(section->name, name))
+			return section;
+	}
+	return NULL;
+}
+
+char * config_get_string(const char *section_str, const char *option, char *def)
+{
+	struct conf_section *section = config_get_section(section_str);
+	if (section != NULL) {
+		struct conf_tupel *tupel;
+		list_for_each_entry(tupel, &section->tupel_list, list) {
+			if (!strcmp(tupel->option, option))
+				return tupel->parameter;
+		}
+	}
+
+	if (def != NULL)
+		log_print(LOG_WARN, "config [%s:%s] not found, using default: '%s'",
+			section_str, option, def);
+	return def;
+}
+
+int config_get_int(const char *section, const char *option, int def)
+{
+	char *ret = config_get_string(section, option, NULL);
+	if (ret == NULL) {
+		log_print(LOG_WARN, "config [%s:%s] not found, using default: '%d'",
+			section, option, def);
+		return def;
+	}
+	return atoi(ret);
+}
+
+int config_get_strings(const char *section_str, const char *option,
+			int (*callback)(const char *value, void *privdata),
+			void *privdata)
+{
+	struct conf_section *section = config_get_section(section_str);
+	if (section == NULL)
+		return -1;
+
+	int cnt = 0;
+	struct conf_tupel *tupel;
+	list_for_each_entry(tupel, &section->tupel_list, list) {
+		if (!strcmp(tupel->option, option))
+			if (callback(tupel->parameter, privdata) == 0)
+				cnt++;
+	}
+	return cnt;
+}

configfile.h

@@ -0,0 +1,16 @@
+#ifndef _CONFIG_H_
+#define _CONFIG_H_
+
+#include <netinet/in.h>
+
+int config_parse(const char *config);
+
+char * config_get_string(const char *section_str, const char *option, char *def);
+
+int config_get_int(const char *section, const char *option, int def);
+
+int config_get_strings(const char *section_str, const char *option,
+			int (*callback)(const char *value, void *privdata),
+			void *privdata);
+
+#endif /* _CONFIG_H_ */

conntrack.c

@@ -0,0 +1,114 @@
+#include <stdlib.h>
+#include <time.h>
+#include <pthread.h>
+
+#include <libnfnetlink/libnfnetlink.h>
+#include <libnetfilter_conntrack/libnetfilter_conntrack.h>
+
+#include "configfile.h"
+#include "logging.h"
+#include "hashtable.h"
+
+#define DEFAULT_HASHSIZE 127
+
+static pthread_t ct_thread;
+
+static struct nfct_handle *cth;
+
+static struct hash_table *table[2];
+static int hash_select = 0;
+
+static int conntrack_event_cb(void *arg, unsigned int flags, int type, void *privdata)
+{
+	struct nfct_conntrack *ct = (struct nfct_conntrack *)arg;
+
+	if (ct->tuple[NFCT_DIR_ORIGINAL].l3protonum != AF_INET)
+		return 0;
+
+	struct hash_entry *entry = malloc(sizeof(struct hash_entry));
+	if (entry == NULL) {
+		log_print(LOG_WARN, "conntrack_event_cb: out of memory");
+		return -1;
+	}
+
+	entry->src_ip = ct->tuple[NFCT_DIR_ORIGINAL].src.v4;
+	entry->protonum = ct->tuple[NFCT_DIR_ORIGINAL].protonum;
+	entry->dst_port = ct->tuple[NFCT_DIR_ORIGINAL].l4dst.tcp.port;
+
+	entry->src_bytes = ct->counters[NFCT_DIR_ORIGINAL].bytes;
+	entry->dst_bytes = ct->counters[NFCT_DIR_REPLY].bytes;
+
+	hash_add(table[hash_select], entry);
+	return 0;
+}
+
+int conntrack_dump_hash(void (*callback)(struct hash_entry *entry, void *privdata), void *privdata)
+{
+	/*
+	 * switch hashtable
+	 * -> conntrack_event_cb will use the empty hash next time, and we dump now the full one
+	 * -> if conntrack_event_cb is running *now* (on the full hash), we have to wait a bit
+	 * -> but since we are faster than dump intervall, conntrack_event_cb never waits
+	 */
+	int used_hash = hash_select;
+	hash_select ^= 0x01;
+
+	purge_hash(table[used_hash], callback, privdata);
+	return 0;
+}
+
+int conntrack_init(void)
+{
+	cth = nfct_open(CONNTRACK, NF_NETLINK_CONNTRACK_DESTROY);
+	if (cth == NULL) {
+		log_print(LOG_ERROR, "conntrack_init: nfct_open()");
+		return -1;
+	}
+
+	int size = config_get_int("global", "hashsize", DEFAULT_HASHSIZE);
+
+	table[0] = create_hash(size);
+	if (table[0] == NULL) {
+		log_print(LOG_ERROR, "conntrack_init: create_hash(0)");
+		nfct_close(cth);
+		return -1;
+	}
+
+	table[1] = create_hash(size);
+	if (table[1] == NULL) {
+		log_print(LOG_ERROR, "conntrack_init: create_hash(1)");
+		destroy_hash(table[0]);
+		nfct_close(cth);
+		return -1;
+	}
+
+	nfct_register_callback(cth, conntrack_event_cb, NULL);
+	return 0;
+}
+
+static int event_thread(void *arg)
+{
+	nfct_event_conntrack(cth);
+	return 0;
+}
+
+int conntrack_start_event_thread(void)
+{
+	/* startup conntrack event listener */
+	pthread_attr_t attr;
+
+	pthread_attr_init(&attr);
+	pthread_attr_setstacksize(&attr, 65536);
+	pthread_create(&ct_thread, &attr, (void *)&event_thread, NULL);
+
+	return 0;
+}
+
+int conntrack_close(void)
+{
+	destroy_hash(table[1]);
+	destroy_hash(table[0]);
+
+	nfct_close(cth);
+	return 0;
+}

conntrack.h

@@ -0,0 +1,12 @@
+#ifndef _CONNTRACK_H_
+#define _CONNTRACK_H_
+
+#include "hashtable.h"
+
+int conntrack_init(void);
+int conntrack_start_event_thread(void);
+int conntrack_close(void);
+
+int conntrack_dump_hash(void (*callback)(struct hash_entry *entry, void *privdata), void *privdata);
+
+#endif // _CONNTRACK_H_

ctstats.c

@@ -0,0 +1,88 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include <string.h>
+#include <getopt.h>
+
+#include "configfile.h"
+#include "conntrack.h"
+#include "database.h"
+#include "logging.h"
+
+#define DEFAULT_CONFIG "ctstats.conf"
+#define DEFAULT_LOGFILE "ctstats.log"
+#define DEFAULT_INTERVALL 300
+
+static struct option opts[] = {
+	{"config",	1, 0, 'c'},
+	{"debug",	0, 0, 'd'},
+	{"help",	0, 0, 'h'},
+	{0, 0, 0, 0}
+};
+
+int main(int argc, char *argv[])
+{
+	char *config = DEFAULT_CONFIG;
+	int code, arg = 0, debug = 0;
+
+	do {
+		code = getopt_long(argc, argv, "c:dh", opts, &arg);
+
+		switch (code) {
+		case 'c':	/* config */
+				config = optarg;
+				break;
+
+		case 'd':	/* debug */
+				debug = 1;
+				break;
+
+		case 'h':	/* help */
+				printf("Usage: ctstat [options]\n"
+					"Options: \n"
+					"  --config       -c  configfile  use this configfile\n"
+					"  --debug        -d              do not fork and log to stderr\n"
+					"  --help         -h              this help\n"
+					"\n");
+				exit(0);
+				break;
+
+		case '?':	/* error */
+				exit(-1);
+				break;
+
+		default:	/* unknown / all options parsed */
+				break;
+		}
+	} while (code != -1);
+
+	/* parse config file */
+	if (config_parse(config))
+		exit(1);
+
+	/* init netlink, hashtables, mutexes */
+	if (conntrack_init())
+		exit(1);
+
+	/* init database connection */
+	if (database_init()) {
+		conntrack_close();
+		exit(1);
+	}
+
+	conntrack_start_event_thread();
+
+	int intervall = config_get_int("global", "intervall", DEFAULT_INTERVALL);
+	while (1) {
+		sleep(intervall);
+
+		/* fill database */
+		database_analyse();
+	}
+
+	/* how to stop? */
+	database_close();
+	conntrack_close();
+	return 0;
+}

ctstats.conf

@@ -0,0 +1,10 @@
+[global]
+intervall 30
+hashsize 127
+logfile ctstats.log
+
+[mysql]
+hostname localhost
+username ctstats
+password ctstats
+database ctstats

database.c

@@ -0,0 +1,52 @@
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+
+#include "conntrack.h"
+#include "database.h"
+#include "hashtable.h"
+#include "logging.h"
+
+static void purge_hash_cb(struct hash_entry *entry, void *privdata)
+{
+	struct in_addr src_ip = { .s_addr = entry->src_ip };
+	char *proto;
+
+	switch (entry->protonum) {
+	case IPPROTO_TCP:
+		proto = "tcp ";
+		break;
+
+	case IPPROTO_UDP:
+		proto = "udp ";
+		break;
+
+	case IPPROTO_ICMP:
+		proto = "icmp";
+		break;
+
+	default:
+		proto = "unkn";
+		break;
+	}
+
+	log_print(LOG_DEBUG, "%4s %15s:%5d -> %8llu / %8llu (%u)",
+		proto, inet_ntoa(src_ip), ntohs(entry->dst_port),
+		entry->src_bytes, entry->dst_bytes, entry->count);
+}
+
+int database_analyse(void)
+{
+	conntrack_dump_hash(purge_hash_cb, NULL);
+	return 0;
+}
+
+int database_init(void)
+{
+	return 0;
+}
+
+int database_close(void)
+{
+	return 0;
+}

database.h

@@ -0,0 +1,8 @@
+#ifndef _DATABASE_H_
+#define _DATABASE_H_
+
+int database_analyse(void);
+int database_init(void);
+int database_close(void);
+
+#endif // _DATABASE_H_

hashtable.c

@@ -0,0 +1,126 @@
+#include <stdlib.h>
+#include <inttypes.h>
+#include <pthread.h>
+
+#include "hashtable.h"
+
+/* see linux/include/linux/jhash.h for details */
+#define JHASH_GOLDEN_RATIO      0x9e3779b9
+#define __jhash_mix(a, b, c) \
+{ \
+	a -= b; a -= c; a ^= (c>>13); \
+	b -= c; b -= a; b ^= (a<<8); \
+	c -= a; c -= b; c ^= (b>>13); \
+	a -= b; a -= c; a ^= (c>>12);  \
+	b -= c; b -= a; b ^= (a<<16); \
+	c -= a; c -= b; c ^= (b>>5); \
+	a -= b; a -= c; a ^= (c>>3);  \
+	b -= c; b -= a; b ^= (a<<10); \
+	c -= a; c -= b; c ^= (b>>15); \
+}
+
+struct hash_table * create_hash(uint32_t buckets)
+{
+	struct hash_table *table;
+	uint32_t i;
+
+	table = malloc(sizeof(struct hash_table) +
+			(sizeof(struct hash_entry *) * buckets));
+
+	if (table == NULL)
+		return NULL;
+
+	for (i = 0; i < buckets; i++)
+		table->bucket[i] = NULL;
+
+	table->buckets = buckets;
+	table->hash_rnd = 0x56789ABC;
+
+	pthread_mutex_init(&table->mutex, NULL);
+	return table;
+}
+
+void purge_hash(struct hash_table *table,
+		void (*callback)(struct hash_entry *entry, void *privdata),
+		void *privdata)
+{
+	uint32_t i;
+	pthread_mutex_lock(&table->mutex);
+
+	for (i = 0; i < table->buckets; i++) {
+		struct hash_entry *entry = table->bucket[i];
+		while (entry != NULL) {
+			struct hash_entry *tmp = entry;
+
+			if (callback != NULL)
+				callback(entry, privdata);
+
+			entry = entry->next;
+			free(tmp);
+		}
+		table->bucket[i] = NULL;
+	}
+
+	pthread_mutex_unlock(&table->mutex);
+}
+
+void destroy_hash(struct hash_table *table)
+{
+	purge_hash(table, NULL, NULL);
+	pthread_mutex_destroy(&table->mutex);
+	free(table);
+}
+
+static uint32_t calc_hashkey(struct hash_entry *entry, uint32_t initval)
+{
+	uint32_t a = entry->src_ip;
+	uint32_t b = entry->protonum;
+	uint32_t c = entry->dst_port;
+
+	a += JHASH_GOLDEN_RATIO;
+	b += JHASH_GOLDEN_RATIO;
+	c += initval;
+
+	__jhash_mix(a, b, c);
+
+	return c;
+}
+
+static int cmp_entry(struct hash_entry *a, struct hash_entry *b)
+{
+	return (a->src_ip ^ b->src_ip) |
+		(a->protonum ^ b->protonum) |
+		(a->dst_port ^ b->dst_port);
+}
+
+void hash_add(struct hash_table *table, struct hash_entry *entry)
+{
+	uint32_t key = calc_hashkey(entry, table->hash_rnd) % table->buckets;
+
+	pthread_mutex_lock(&table->mutex);
+
+	struct hash_entry *search = table->bucket[key];
+	/* search collision-list */
+	while (search != NULL) {
+		if (cmp_entry(entry, search) == 0) {
+			/* add values */
+			search->src_bytes += entry->src_bytes;
+			search->dst_bytes += entry->dst_bytes;
+			search->count++;
+
+			pthread_mutex_unlock(&table->mutex);
+
+			/* free entry */
+			free(entry);
+			return;
+		}
+		search = search->next;
+	}
+
+	/* insert new bucket */
+	entry->count = 1;
+	entry->next = table->bucket[key];
+	table->bucket[key] = entry;
+
+	pthread_mutex_unlock(&table->mutex);
+}

hashtable.h

@@ -0,0 +1,35 @@
+#ifndef _HASHTABLE_H_
+#define _HASHTABLE_H_
+
+#include <inttypes.h>
+#include <pthread.h>
+
+struct hash_entry {
+	struct hash_entry *next;
+	uint32_t src_ip;
+	uint16_t protonum;
+	uint16_t dst_port;
+
+	uint64_t src_bytes;
+	uint64_t dst_bytes;
+	uint32_t count;
+};
+
+struct hash_table {
+	uint32_t buckets;
+	uint32_t hash_rnd;
+	pthread_mutex_t mutex;
+	struct hash_entry *bucket[0];
+};
+
+struct hash_table * create_hash(uint32_t buckets);
+
+void purge_hash(struct hash_table *table,
+		void (*callback)(struct hash_entry *entry, void *privdata),
+		void *privdata);
+
+void destroy_hash(struct hash_table *table);
+
+void hash_add(struct hash_table *table, struct hash_entry *entry);
+
+#endif /* _HASHTABLE_H_ */

list.h

@@ -0,0 +1,268 @@
+#ifndef _LIST_H_
+#define _LIST_H_
+
+/*
+ * stolen from linux kernel 2.6.11 (http://kernel.org/)
+ * linux/include/linux/stddef.h (offsetoff)
+ * linux/include/linux/kernel.h (container_of)
+ * linux/include/linux/list.h (*list*)
+ * linux/include/linux/netfilter_ipv4/listhelp.h (LIST_FIND)
+ *
+ * modified by Olaf Rempel <razzor@kopf-tisch.de>
+ */
+#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
+
+#define container_of(ptr, type, member) ({ \
+		const typeof( ((type *)0)->member ) *__mptr = (ptr); \
+		(type *)( (char *)__mptr - offsetof(type,member) );})
+
+struct list_head {
+	struct list_head *next, *prev;
+};
+
+#define LIST_HEAD_INIT(name) { &(name), &(name) }
+
+#define LIST_HEAD(name) \
+	struct list_head name = LIST_HEAD_INIT(name)
+
+#define INIT_LIST_HEAD(ptr) do { \
+	(ptr)->next = (ptr); (ptr)->prev = (ptr); \
+} while (0)
+
+/*
+ * Insert a new entry between two known consecutive entries.
+ *
+ * This is only for internal list manipulation where we know
+ * the prev/next entries already!
+ */
+static inline void __list_add(struct list_head *new,
+			      struct list_head *prev,
+			      struct list_head *next)
+{
+	next->prev = new;
+	new->next = next;
+	new->prev = prev;
+	prev->next = new;
+}
+
+/*
+ * list_add - add a new entry
+ * @new: new entry to be added
+ * @head: list head to add it after
+ *
+ * Insert a new entry after the specified head.
+ * This is good for implementing stacks.
+ */
+static inline void list_add(struct list_head *new, struct list_head *head)
+{
+	__list_add(new, head, head->next);
+}
+
+/*
+ * list_add_tail - add a new entry
+ * @new: new entry to be added
+ * @head: list head to add it before
+ *
+ * Insert a new entry before the specified head.
+ * This is useful for implementing queues.
+ */
+static inline void list_add_tail(struct list_head *new, struct list_head *head)
+{
+	__list_add(new, head->prev, head);
+}
+
+/*
+ * Delete a list entry by making the prev/next entries
+ * point to each other.
+ *
+ * This is only for internal list manipulation where we know
+ * the prev/next entries already!
+ */
+static inline void __list_del(struct list_head * prev, struct list_head * next)
+{
+	next->prev = prev;
+	prev->next = next;
+}
+
+/*
+ * list_del - deletes entry from list.
+ * @entry: the element to delete from the list.
+ * Note: list_empty on entry does not return true after this, the entry is
+ * in an undefined state.
+ */
+static inline void list_del(struct list_head *entry)
+{
+	__list_del(entry->prev, entry->next);
+	entry->next = NULL;
+	entry->prev = NULL;
+}
+
+/*
+ * list_del_init - deletes entry from list and reinitialize it.
+ * entry: the element to delete from the list.
+ */
+static inline void list_del_init(struct list_head *entry)
+{
+	__list_del(entry->prev, entry->next);
+	INIT_LIST_HEAD(entry);
+}
+
+/*
+ * list_move - delete from one list and add as another's head
+ * @list: the entry to move
+ * @head: the head that will precede our entry
+ */
+static inline void list_move(struct list_head *list, struct list_head *head)
+{
+        __list_del(list->prev, list->next);
+        list_add(list, head);
+}
+
+/*
+ * list_move_tail - delete from one list and add as another's tail
+ * @list: the entry to move
+ * @head: the head that will follow our entry
+ */
+static inline void list_move_tail(struct list_head *list,
+				  struct list_head *head)
+{
+        __list_del(list->prev, list->next);
+        list_add_tail(list, head);
+}
+
+/*
+ * list_empty - tests whether a list is empty
+ * @head: the list to test.
+ */
+static inline int list_empty(const struct list_head *head)
+{
+	return head->next == head;
+}
+
+static inline void __list_splice(struct list_head *list,
+				 struct list_head *head)
+{
+	struct list_head *first = list->next;
+	struct list_head *last = list->prev;
+	struct list_head *at = head->next;
+
+	first->prev = head;
+	head->next = first;
+
+	last->next = at;
+	at->prev = last;
+}
+
+/*
+ * list_splice - join two lists
+ * @list: the new list to add.
+ * @head: the place to add it in the first list.
+ */
+static inline void list_splice(struct list_head *list, struct list_head *head)
+{
+	if (!list_empty(list))
+		__list_splice(list, head);
+}
+
+/*
+ * list_splice_init - join two lists and reinitialise the emptied list.
+ * @list: the new list to add.
+ * @head: the place to add it in the first list.
+ *
+ * The list at @list is reinitialised
+ */
+static inline void list_splice_init(struct list_head *list,
+				    struct list_head *head)
+{
+	if (!list_empty(list)) {
+		__list_splice(list, head);
+		INIT_LIST_HEAD(list);
+	}
+}
+
+/*
+ * list_entry - get the struct for this entry
+ * @ptr:	the &struct list_head pointer.
+ * @type:	the type of the struct this is embedded in.
+ * @member:	the name of the list_struct within the struct.
+ */
+#define list_entry(ptr, type, member) \
+	container_of(ptr, type, member)
+
+/*
+ * list_for_each	-	iterate over a list
+ * @pos:	the &struct list_head to use as a loop counter.
+ * @head:	the head for your list.
+ */
+#define list_for_each(pos, head) \
+	for (pos = (head)->next; pos != (head); pos = pos->next)
+
+/*
+ * list_for_each_prev	-	iterate over a list backwards
+ * @pos:	the &struct list_head to use as a loop counter.
+ * @head:	the head for your list.
+ */
+#define list_for_each_prev(pos, head) \
+	for (pos = (head)->prev; pos != (head); pos = pos->prev)
+
+/*
+ * list_for_each_safe	-	iterate over a list safe against removal of list entry
+ * @pos:	the &struct list_head to use as a loop counter.
+ * @n:		another &struct list_head to use as temporary storage
+ * @head:	the head for your list.
+ */
+#define list_for_each_safe(pos, n, head) \
+	for (pos = (head)->next, n = pos->next; pos != (head); \
+		pos = n, n = pos->next)
+
+/*
+ * list_for_each_entry	-	iterate over list of given type
+ * @pos:	the type * to use as a loop counter.
+ * @head:	the head for your list.
+ * @member:	the name of the list_struct within the struct.
+ */
+#define list_for_each_entry(pos, head, member)				\
+	for (pos = list_entry((head)->next, typeof(*pos), member);	\
+	     &pos->member != (head); 					\
+	     pos = list_entry(pos->member.next, typeof(*pos), member))
+
+/*
+ * list_for_each_entry_reverse - iterate backwards over list of given type.
+ * @pos:	the type * to use as a loop counter.
+ * @head:	the head for your list.
+ * @member:	the name of the list_struct within the struct.
+ */
+#define list_for_each_entry_reverse(pos, head, member)			\
+	for (pos = list_entry((head)->prev, typeof(*pos), member);	\
+	     &pos->member != (head); 					\
+	     pos = list_entry(pos->member.prev, typeof(*pos), member))
+
+/*
+ * list_for_each_entry_safe - iterate over list of given type safe against removal of list entry
+ * @pos:	the type * to use as a loop counter.
+ * @n:		another type * to use as temporary storage
+ * @head:	the head for your list.
+ * @member:	the name of the list_struct within the struct.
+ */
+#define list_for_each_entry_safe(pos, n, head, member)			\
+	for (pos = list_entry((head)->next, typeof(*pos), member),	\
+		n = list_entry(pos->member.next, typeof(*pos), member);	\
+	     &pos->member != (head); 					\
+	     pos = n, n = list_entry(n->member.next, typeof(*n), member))
+
+
+/* Return pointer to first true entry, if any, or NULL.  A macro
+   required to allow inlining of cmpfn. */
+#define LIST_FIND(head, cmpfn, type, args...)           \
+({                                                      \
+        const struct list_head *__i, *__j = NULL;       \
+                                                        \
+        list_for_each(__i, (head))                      \
+                if (cmpfn((const type)__i , ## args)) { \
+                        __j = __i;                      \
+                        break;                          \
+                }                                       \
+        (type)__j;                                      \
+})
+
+#endif /* _LIST_H_ */

logging.c

@@ -0,0 +1,103 @@
+/***************************************************************************
+ *   Copyright (C) 06/2006 by Olaf Rempel                                  *
+ *   razzor@kopf-tisch.de                                                  *
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ *   This program is distributed in the hope that it will be useful,       *
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
+ *   GNU General Public License for more details.                          *
+ *                                                                         *
+ *   You should have received a copy of the GNU General Public License     *
+ *   along with this program; if not, write to the                         *
+ *   Free Software Foundation, Inc.,                                       *
+ *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
+ ***************************************************************************/
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include <stdarg.h>
+#include <errno.h>
+#include <string.h>
+
+#include "logging.h"
+
+#define BUFSIZE 8192
+
+static FILE *log_fd = NULL;
+static char *buffer = NULL;
+
+void log_print(int prio, const char *fmt, ...)
+{
+	va_list az;
+	int len;
+
+	if (buffer == NULL) {
+		buffer = malloc(BUFSIZE);
+		if (buffer == NULL) {
+			fprintf(stderr, "log_print: out of memory\nBailing out!\n");
+			exit(-1);
+		}
+	}
+
+	va_start(az, fmt);
+	len = vsnprintf(buffer, BUFSIZE, fmt, az);
+	va_end(az);
+
+	if (len < 0 || len >= BUFSIZE) {
+		log_print(LOG_ERROR, "log_print: arguments too long");
+		errno = 0;
+		return;
+	}
+
+	if (errno) {
+		strncpy(buffer + len, ": ", BUFSIZE - len);
+		len += 2;
+		strncpy(buffer + len, strerror(errno), BUFSIZE - len);
+	}
+
+	if (log_fd) {
+		char    tbuf[64];
+		time_t  tzgr;
+
+		time(&tzgr);
+		strftime(tbuf, sizeof(tbuf), "%b %d %H:%M:%S :", localtime(&tzgr));
+
+		fprintf(log_fd, "%s %s\n", tbuf, buffer);
+		fflush(log_fd);
+
+	} else {
+		fprintf(stderr, "%s\n", buffer);
+	}
+
+	errno = 0;
+}
+
+static void log_close(void)
+{
+	if (buffer)
+		free(buffer);
+
+	fclose(log_fd);
+}
+
+int log_init(char *logfile)
+{
+	log_fd = fopen(logfile, "a");
+	if (log_fd == NULL) {
+		log_print(LOG_ERROR, "log_open('%s'): %s", logfile);
+		return 0;
+	}
+
+	if (atexit(log_close) != 0) {
+		log_print(LOG_ERROR, "log_open(): atexit()");
+		return 0;
+	}
+
+	log_print(LOG_EVERYTIME, "==========================");
+	return 1;
+}

logging.h

@@ -0,0 +1,16 @@
+#ifndef _LOGGING_H_
+#define _LOGGING_H_
+
+#define LOG_DEBUG 5
+#define LOG_INFO  4
+#define LOG_NOTICE 3
+#define LOG_WARN 2
+#define LOG_ERROR 1
+#define LOG_CRIT 0
+
+#define LOG_EVERYTIME 0
+
+int log_init(char *logfile);
+void log_print(int prio, const char *fmt, ... );
+
+#endif /* _LOGGING_H_ */