Add function prototypes and base module for kernel side iconv library.

Add simple "xlat" converter which performs 8to8 table based conversion.
Unicode converter will be added in the near future.

Reviewed by:			silence on arch@
Files placement reviewed by:	bde
Obtained from:			smbfs

9 files changed, 840 insertions, 1 deletions

diff --git a/sys/conf/NOTES b/sys/conf/NOTES
index b1456ae..3513ef3 100644
--- a/sys/conf/NOTES
+++ b/sys/conf/NOTES
@@ -978,6 +978,9 @@ device		ccd	4	#Concatenated disk driver
 device		vinum		#Vinum concat/mirror/raid driver
 options 	VINUMDEBUG	#enable Vinum debugging hooks
 
+# Kernel side iconv library
+options 	LIBICONV
+
 # Size of the kernel message buffer.  Should be N * pagesize.
 options 	MSGBUF_SIZE=40960
 
diff --git a/sys/conf/files b/sys/conf/files
index 5dddc37..604189c 100644
--- a/sys/conf/files
+++ b/sys/conf/files
@@ -764,6 +764,9 @@ kern/vfs_vnops.c	standard
 libkern/arc4random.c	standard
 libkern/bcd.c		standard
 libkern/bsearch.c	standard
+libkern/iconv.c		optional libiconv
+libkern/iconv_converter_if.m	optional libiconv
+libkern/iconv_xlat.c	optional libiconv
 libkern/index.c		standard
 libkern/inet_ntoa.c	standard
 libkern/mcount.c	optional	profiling-routine
diff --git a/sys/conf/kmod.mk b/sys/conf/kmod.mk
index 31d8f18..7a279f3 100644
--- a/sys/conf/kmod.mk
+++ b/sys/conf/kmod.mk
@@ -272,7 +272,9 @@ ${_src}:
 .endfor
 
 MFILES?= kern/bus_if.m kern/device_if.m dev/iicbus/iicbb_if.m \
-    dev/iicbus/iicbus_if.m isa/isa_if.m dev/mii/miibus_if.m \
+    dev/iicbus/iicbus_if.m isa/isa_if.m \
+    libkern/iconv_converter_if.m \
+    dev/mii/miibus_if.m \
     dev/pccard/card_if.m dev/pccard/power_if.m dev/pci/pci_if.m \
     dev/pci/pcib_if.m dev/ppbus/ppbus_if.m dev/smbus/smbus_if.m \
     dev/usb/usb_if.m dev/sound/pcm/ac97_if.m dev/sound/pcm/channel_if.m \
diff --git a/sys/conf/options b/sys/conf/options
index d4c375a..07dff22 100644
--- a/sys/conf/options
+++ b/sys/conf/options
@@ -65,6 +65,7 @@ GDB_REMOTE_CHAT	opt_ddb.h
 DEVFS
 HW_WDOG
 KTRACE
+LIBICONV
 MD_ROOT		opt_md.h
 MD_ROOT_SIZE	opt_md.h
 MFS_ROOT	opt_mfs.h
diff --git a/sys/i386/conf/NOTES b/sys/i386/conf/NOTES
index b1456ae..3513ef3 100644
--- a/sys/i386/conf/NOTES
+++ b/sys/i386/conf/NOTES
@@ -978,6 +978,9 @@ device		ccd	4	#Concatenated disk driver
 device		vinum		#Vinum concat/mirror/raid driver
 options 	VINUMDEBUG	#enable Vinum debugging hooks
 
+# Kernel side iconv library
+options 	LIBICONV
+
 # Size of the kernel message buffer.  Should be N * pagesize.
 options 	MSGBUF_SIZE=40960
 
diff --git a/sys/libkern/iconv.c b/sys/libkern/iconv.c
new file mode 100644
index 0000000..8eafa28
--- /dev/null
+++ b/sys/libkern/iconv.c
@@ -0,0 +1,479 @@
+/*
+ * Copyright (c) 2000-2001, Boris Popov
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *    This product includes software developed by Boris Popov.
+ * 4. Neither the name of the author nor the names of any co-contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/kernel.h>
+#include <sys/iconv.h>
+#include <sys/malloc.h>
+
+#include "iconv_converter_if.h"
+
+SYSCTL_DECL(_kern_iconv);
+
+SYSCTL_NODE(_kern, OID_AUTO, iconv, CTLFLAG_RW, NULL, "kernel iconv interface");
+
+MALLOC_DEFINE(M_ICONV, "ICONV", "ICONV structures");
+MALLOC_DEFINE(M_ICONVDATA, "ICONV data", "ICONV data");
+
+MODULE_VERSION(libiconv, 1);
+
+#ifdef notnow
+/*
+ * iconv converter instance
+ */
+struct iconv_converter {
+	KOBJ_FIELDS;
+	void *			c_data;
+};
+#endif
+
+struct sysctl_oid *iconv_oid_hook = &sysctl___kern_iconv;
+
+/*
+ * List of loaded converters
+ */
+static TAILQ_HEAD(iconv_converter_list, iconv_converter_class)
+    iconv_converters = TAILQ_HEAD_INITIALIZER(iconv_converters);
+
+/*
+ * List of supported/loaded charsets pairs
+ */
+static TAILQ_HEAD(, iconv_cspair)
+    iconv_cslist = TAILQ_HEAD_INITIALIZER(iconv_cslist);
+static int iconv_csid = 1;
+
+static char iconv_unicode_string[] = "unicode";	/* save eight bytes when possible */
+
+static void iconv_unregister_cspair(struct iconv_cspair *csp);
+
+static int
+iconv_mod_unload(void)
+{
+	struct iconv_cspair *csp;
+
+	while ((csp = TAILQ_FIRST(&iconv_cslist)) != NULL) {
+		if (csp->cp_refcount)
+			return EBUSY;
+		iconv_unregister_cspair(csp);
+	}
+	return 0;
+}
+
+static int
+iconv_mod_handler(module_t mod, int type, void *data)
+{
+	int error;
+
+	switch (type) {
+	    case MOD_LOAD:
+		error = 0;
+		break;
+	    case MOD_UNLOAD:
+		error = iconv_mod_unload();
+		break;
+	    default:
+		error = EINVAL;
+	}
+	return error;
+}
+
+static moduledata_t iconv_mod = {
+	"iconv", iconv_mod_handler, NULL
+};
+
+DECLARE_MODULE(iconv, iconv_mod, SI_SUB_DRIVERS, SI_ORDER_SECOND);
+
+static int
+iconv_register_converter(struct iconv_converter_class *dcp)
+{
+	kobj_class_compile((struct kobj_class*)dcp);
+	dcp->refs++;
+	TAILQ_INSERT_TAIL(&iconv_converters, dcp, cc_link);
+	return 0;
+}
+
+static int
+iconv_unregister_converter(struct iconv_converter_class *dcp)
+{
+	if (dcp->refs > 1) {
+		ICDEBUG("converter have %d referenses left\n", dcp->refs);
+		return EBUSY;
+	}
+	TAILQ_REMOVE(&iconv_converters, dcp, cc_link);
+	kobj_class_free((struct kobj_class*)dcp);
+	return 0;
+}
+
+static int
+iconv_lookupconv(const char *name, struct iconv_converter_class **dcpp)
+{
+	struct iconv_converter_class *dcp;
+
+	TAILQ_FOREACH(dcp, &iconv_converters, cc_link) {
+		if (name == NULL)
+			continue;
+		if (strcmp(name, ICONV_CONVERTER_NAME(dcp)) == 0) {
+			if (dcpp)
+				*dcpp = dcp;
+			return 0;
+		}
+	}
+	return ENOENT;
+}
+
+static int
+iconv_lookupcs(const char *to, const char *from, struct iconv_cspair **cspp)
+{
+	struct iconv_cspair *csp;
+
+	TAILQ_FOREACH(csp, &iconv_cslist, cp_link) {
+		if (strcmp(csp->cp_to, to) == 0 &&
+		    strcmp(csp->cp_from, from) == 0) {
+			if (cspp)
+				*cspp = csp;
+			return 0;
+		}
+	}
+	return ENOENT;
+}
+
+static int
+iconv_register_cspair(const char *to, const char *from,
+	struct iconv_converter_class *dcp, void *data,
+	struct iconv_cspair **cspp)
+{
+	struct iconv_cspair *csp;
+	char *cp;
+	int csize, ucsto, ucsfrom;
+
+	if (iconv_lookupcs(to, from, NULL) == 0)
+		return EEXIST;
+	csize = sizeof(*csp);
+	ucsto = strcmp(to, iconv_unicode_string) == 0;
+	if (!ucsto)
+		csize += strlen(to) + 1;
+	ucsfrom = strcmp(from, iconv_unicode_string) == 0;
+	if (!ucsfrom)
+		csize += strlen(from) + 1;
+	csp = malloc(csize, M_ICONV, M_WAITOK);
+	bzero(csp, csize);
+	csp->cp_id = iconv_csid++;
+	csp->cp_dcp = dcp;
+	cp = (char*)(csp + 1);
+	if (!ucsto) {
+		strcpy(cp, to);
+		csp->cp_to = cp;
+		cp += strlen(cp) + 1;
+	} else
+		csp->cp_to = iconv_unicode_string;
+	if (!ucsfrom) {
+		strcpy(cp, from);
+		csp->cp_from = cp;
+	} else
+		csp->cp_from = iconv_unicode_string;
+	csp->cp_data = data;
+
+	TAILQ_INSERT_TAIL(&iconv_cslist, csp, cp_link);
+	*cspp = csp;
+	return 0;
+}
+
+static void
+iconv_unregister_cspair(struct iconv_cspair *csp)
+{
+	TAILQ_REMOVE(&iconv_cslist, csp, cp_link);
+	if (csp->cp_data)
+		free(csp->cp_data, M_ICONVDATA);
+	free(csp, M_ICONV);
+}
+
+/*
+ * Lookup and create an instance of converter.
+ * Currently this layer didn't have associated 'instance' structure
+ * to avoid unnesessary memory allocation.
+ */
+int
+iconv_open(const char *to, const char *from, void **handle)
+{
+	struct iconv_cspair *csp, *cspfrom, *cspto;
+	struct iconv_converter_class *dcp;
+	const char *cnvname;
+	int error;
+
+	/*
+	 * First, lookup fully qualified cspairs
+	 */
+	error = iconv_lookupcs(to, from, &csp);
+	if (error == 0)
+		return ICONV_CONVERTER_OPEN(csp->cp_dcp, csp, NULL, handle);
+
+	/*
+	 * Well, nothing found. Now try to construct a composite conversion
+	 * ToDo: add a 'capability' field to converter
+	 */
+	TAILQ_FOREACH(dcp, &iconv_converters, cc_link) {
+		cnvname = ICONV_CONVERTER_NAME(dcp);
+		if (cnvname == NULL)
+			continue;
+		error = iconv_lookupcs(cnvname, from, &cspfrom);
+		if (error)
+			continue;
+		error = iconv_lookupcs(to, cnvname, &cspto);
+		if (error)
+			continue;
+		/*
+		 * Fine, we're found a pair which can be combined together
+		 */
+		return ICONV_CONVERTER_OPEN(dcp, cspto, cspfrom, handle);
+	}
+	return ENOENT;
+}
+
+int
+iconv_close(void *handle)
+{
+	return ICONV_CONVERTER_CLOSE(handle);
+}
+
+int
+iconv_conv(void *handle, const char **inbuf,
+	size_t *inbytesleft, char **outbuf, size_t *outbytesleft)
+{
+	return ICONV_CONVERTER_CONV(handle, inbuf, inbytesleft, outbuf, outbytesleft);
+}
+
+/*
+ * Give a list of loaded converters. Each name terminated with 0.
+ * An empty string terminates the list.
+ */
+static int
+iconv_sysctl_drvlist(SYSCTL_HANDLER_ARGS)
+{
+	struct iconv_converter_class *dcp;
+	const char *name;
+	char spc;
+	int error;
+
+	error = 0;
+
+	TAILQ_FOREACH(dcp, &iconv_converters, cc_link) {
+		name = ICONV_CONVERTER_NAME(dcp);
+		if (name == NULL)
+			continue;
+		error = SYSCTL_OUT(req, name, strlen(name) + 1);
+		if (error)
+			break;
+	}
+	if (error)
+		return error;
+	spc = 0;
+	error = SYSCTL_OUT(req, &spc, sizeof(spc));
+	return error;
+}
+
+SYSCTL_PROC(_kern_iconv, OID_AUTO, drvlist, CTLFLAG_RD | CTLTYPE_OPAQUE,
+	    NULL, 0, iconv_sysctl_drvlist, "S,xlat", "registered converters");
+
+/*
+ * List all available charset pairs.
+ */
+static int
+iconv_sysctl_cslist(SYSCTL_HANDLER_ARGS)
+{
+	struct iconv_cspair *csp;
+	struct iconv_cspair_info csi;
+	int error;
+
+	error = 0;
+	bzero(&csi, sizeof(csi));
+	csi.cs_version = ICONV_CSPAIR_INFO_VER;
+
+	TAILQ_FOREACH(csp, &iconv_cslist, cp_link) {
+		csi.cs_id = csp->cp_id;
+		csi.cs_refcount = csp->cp_refcount;
+		csi.cs_base = csp->cp_base ? csp->cp_base->cp_id : 0;
+		strcpy(csi.cs_to, csp->cp_to);
+		strcpy(csi.cs_from, csp->cp_from);
+		error = SYSCTL_OUT(req, &csi, sizeof(csi));
+		if (error)
+			break;
+	}
+	return error;
+}
+
+SYSCTL_PROC(_kern_iconv, OID_AUTO, cslist, CTLFLAG_RD | CTLTYPE_OPAQUE,
+	    NULL, 0, iconv_sysctl_cslist, "S,xlat", "registered charset pairs");
+
+/*
+ * Add new charset pair
+ */
+static int
+iconv_sysctl_add(SYSCTL_HANDLER_ARGS)
+{
+	struct iconv_converter_class *dcp;
+	struct iconv_cspair *csp;
+	struct iconv_add_in din;
+	struct iconv_add_out dout;
+	int error;
+
+	error = SYSCTL_IN(req, &din, sizeof(din));
+	if (error)
+		return error;
+	if (din.ia_version != ICONV_ADD_VER)
+		return EINVAL;
+	if (din.ia_datalen > ICONV_CSMAXDATALEN)
+		return EINVAL;
+	if (iconv_lookupconv(din.ia_converter, &dcp) != 0)
+		return EINVAL;
+	error = iconv_register_cspair(din.ia_to, din.ia_from, dcp, NULL, &csp);
+	if (error)
+		return error;
+	if (din.ia_datalen) {
+		csp->cp_data = malloc(din.ia_datalen, M_ICONVDATA, M_WAITOK);
+		error = copyin(din.ia_data, csp->cp_data, din.ia_datalen);
+		if (error)
+			goto bad;
+	}
+	dout.ia_csid = csp->cp_id;
+	error = SYSCTL_OUT(req, &dout, sizeof(dout));
+	if (error)
+		goto bad;
+	return 0;
+bad:
+	iconv_unregister_cspair(csp);
+	return error;
+}
+
+SYSCTL_PROC(_kern_iconv, OID_AUTO, add, CTLFLAG_RW | CTLTYPE_OPAQUE,
+	    NULL, 0, iconv_sysctl_add, "S,xlat", "register charset pair");
+
+/*
+ * Default stubs for converters
+ */
+int
+iconv_converter_initstub(struct iconv_converter_class *dp)
+{
+	return 0;
+}
+
+int
+iconv_converter_donestub(struct iconv_converter_class *dp)
+{
+	return 0;
+}
+
+int
+iconv_converter_handler(module_t mod, int type, void *data)
+{
+	struct iconv_converter_class *dcp = data;
+	int error;
+
+	switch (type) {
+	    case MOD_LOAD:
+		error = iconv_register_converter(dcp);
+		if (error)
+			break;
+		error = ICONV_CONVERTER_INIT(dcp);
+		if (error)
+			iconv_unregister_converter(dcp);
+		break;
+	    case MOD_UNLOAD:
+		ICONV_CONVERTER_DONE(dcp);
+		error = iconv_unregister_converter(dcp);
+		break;
+	    default:
+		error = EINVAL;
+	}
+	return error;
+}
+
+/*
+ * Common used functions
+ */
+char *
+iconv_convstr(void *handle, char *dst, const char *src)
+{
+	char *p = dst;
+	int inlen, outlen, error;
+
+	if (handle == NULL) {
+		strcpy(dst, src);
+		return dst;
+	}
+	inlen = outlen = strlen(src);
+	error = iconv_conv(handle, NULL, NULL, &p, &outlen);
+	if (error)
+		return NULL;
+	error = iconv_conv(handle, &src, &inlen, &p, &outlen);
+	if (error)
+		return NULL;
+	*p = 0;
+	return dst;
+}
+
+void *
+iconv_convmem(void *handle, void *dst, const void *src, int size)
+{
+	const char *s = src;
+	char *d = dst;
+	int inlen, outlen, error;
+
+	if (size == 0)
+		return dst;
+	if (handle == NULL) {
+		memcpy(dst, src, size);
+		return dst;
+	}
+	inlen = outlen = size;
+	error = iconv_conv(handle, NULL, NULL, &d, &outlen);
+	if (error)
+		return NULL;
+	error = iconv_conv(handle, &s, &inlen, &d, &outlen);
+	if (error)
+		return NULL;
+	return dst;
+}
+
+int
+iconv_lookupcp(char **cpp, const char *s)
+{
+	if (cpp == NULL) {
+		ICDEBUG("warning a NULL list passed\n");
+		return ENOENT;
+	}
+	for (; *cpp; cpp++)
+		if (strcmp(*cpp, s) == 0)
+			return 0;
+	return ENOENT;
+}
diff --git a/sys/libkern/iconv_converter_if.m b/sys/libkern/iconv_converter_if.m
new file mode 100644
index 0000000..0b2901c
--- /dev/null
+++ b/sys/libkern/iconv_converter_if.m
@@ -0,0 +1,68 @@
+#
+# Copyright (c) 2000-2001, Boris Popov
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+# 3. All advertising materials mentioning features or use of this software
+#    must display the following acknowledgement:
+#    This product includes software developed by Boris Popov.
+# 4. Neither the name of the author nor the names of any co-contributors
+#    may be used to endorse or promote products derived from this software
+#    without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+#
+# $FreeBSD$
+#
+
+#include <sys/iconv.h>
+
+INTERFACE iconv_converter;
+
+STATICMETHOD int open {
+	struct iconv_converter_class *dcp;
+	struct iconv_cspair *cspto;
+	struct iconv_cspair *cspfrom;
+	void **hpp;
+};
+
+METHOD int close {
+	void *handle;
+};
+
+METHOD int conv {
+	void *handle;
+	const char **inbuf;
+        size_t *inbytesleft;
+	char **outbuf;
+	size_t *outbytesleft;
+};
+
+STATICMETHOD int init {
+	struct iconv_converter_class *dcp;
+} DEFAULT iconv_converter_initstub;
+
+STATICMETHOD void done {
+	struct iconv_converter_class *dcp;
+} DEFAULT iconv_converter_donestub;
+
+STATICMETHOD const char * name {
+	struct iconv_converter_class *dcp;
+};
diff --git a/sys/libkern/iconv_xlat.c b/sys/libkern/iconv_xlat.c
new file mode 100644
index 0000000..6dd2800
--- /dev/null
+++ b/sys/libkern/iconv_xlat.c
@@ -0,0 +1,124 @@
+/*
+ * Copyright (c) 2000-2001, Boris Popov
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *    This product includes software developed by Boris Popov.
+ * 4. Neither the name of the author nor the names of any co-contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+#include <sys/param.h>
+#include <sys/kernel.h>
+#include <sys/systm.h>
+#include <sys/malloc.h>
+#include <sys/iconv.h>
+
+#include "iconv_converter_if.h"
+
+/*
+ * "XLAT" converter
+ */
+
+#ifdef MODULE_DEPEND
+MODULE_DEPEND(iconv_xlat, libiconv, 1, 1, 1);
+#endif
+
+/*
+ * XLAT converter instance
+ */
+struct iconv_xlat {
+	KOBJ_FIELDS;
+	u_char *		d_table;
+	struct iconv_cspair *	d_csp;
+};
+
+static int
+iconv_xlat_open(struct iconv_converter_class *dcp,
+	struct iconv_cspair *csp, struct iconv_cspair *cspf, void **dpp)
+{
+	struct iconv_xlat *dp;
+
+	dp = (struct iconv_xlat *)kobj_create((struct kobj_class*)dcp, M_ICONV, M_WAITOK);
+	dp->d_table = csp->cp_data;
+	dp->d_csp = csp;
+	csp->cp_refcount++;
+	*dpp = (void*)dp;
+	return 0;
+}
+
+static int
+iconv_xlat_close(void *data)
+{
+	struct iconv_xlat *dp = data;
+
+	dp->d_csp->cp_refcount--;
+	kobj_delete((struct kobj*)data, M_ICONV);
+	return 0;
+}
+
+static int
+iconv_xlat_conv(void *d2p, const char **inbuf,
+	size_t *inbytesleft, char **outbuf, size_t *outbytesleft)
+{
+	struct iconv_xlat *dp = (struct iconv_xlat*)d2p;
+	const char *src;
+	char *dst;
+	int n, r;
+
+	if (inbuf == NULL || *inbuf == NULL || outbuf == NULL || *outbuf == NULL)
+		return 0;
+	r = n = min(*inbytesleft, *outbytesleft);
+	src = *inbuf;
+	dst = *outbuf;
+	while(r--)
+		*dst++ = dp->d_table[(u_char)*src++];
+	*inbuf += n;
+	*outbuf += n;
+	*inbytesleft += n;
+	*outbytesleft -= n;
+	return 0;
+}
+
+static const char *
+iconv_xlat_name(struct iconv_converter_class *dcp)
+{
+	return "xlat";
+}
+
+static kobj_method_t iconv_xlat_methods[] = {
+	KOBJMETHOD(iconv_converter_open,	iconv_xlat_open),
+	KOBJMETHOD(iconv_converter_close,	iconv_xlat_close),
+	KOBJMETHOD(iconv_converter_conv,	iconv_xlat_conv),
+#if 0
+	KOBJMETHOD(iconv_converter_init,	iconv_xlat_init),
+	KOBJMETHOD(iconv_converter_done,	iconv_xlat_done),
+#endif
+	KOBJMETHOD(iconv_converter_name,	iconv_xlat_name),
+	{0, 0}
+};
+
+KICONV_CONVERTER(xlat, sizeof(struct iconv_xlat));
diff --git a/sys/sys/iconv.h b/sys/sys/iconv.h
new file mode 100644
index 0000000..4764aaf
--- /dev/null
+++ b/sys/sys/iconv.h
@@ -0,0 +1,156 @@
+/*
+ * Copyright (c) 2000-2001, Boris Popov
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *    This product includes software developed by Boris Popov.
+ * 4. Neither the name of the author nor the names of any co-contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+#ifndef _SYS_ICONV_H_
+#define _SYS_ICONV_H_
+
+#define	ICONV_CSNMAXLEN		31	/* maximum length of charset name */
+#define	ICONV_CNVNMAXLEN	31	/* maximum length of converter name */
+#define	ICONV_CSMAXDATALEN	1024	/* maximum size of data associated with cs pair */
+
+/*
+ * Entry for cslist sysctl
+ */
+#define	ICONV_CSPAIR_INFO_VER	1
+
+struct iconv_cspair_info {
+	int	cs_version;
+	int	cs_id;
+	int	cs_base;
+	int	cs_refcount;
+	char	cs_to[ICONV_CSNMAXLEN];
+	char	cs_from[ICONV_CSNMAXLEN];
+};
+
+/*
+ * Paramters for 'add' sysctl
+ */
+#define	ICONV_ADD_VER	1
+
+struct iconv_add_in {
+	int	ia_version;
+	char	ia_converter[ICONV_CNVNMAXLEN];
+	char	ia_to[ICONV_CSNMAXLEN];
+	char	ia_from[ICONV_CSNMAXLEN];
+	int	ia_datalen;
+	const void *ia_data;
+};
+
+struct iconv_add_out {
+	int	ia_csid;
+};
+
+#ifndef _KERNEL
+
+__BEGIN_DECLS
+
+int   kiconv_add_xlat_table(const char *, const char *, const u_char *);
+
+__END_DECLS
+
+#else /* !_KERNEL */
+
+#include <sys/kobj.h>
+#include <sys/queue.h>			/* can't avoid that */
+#include <sys/sysctl.h>			/* can't avoid that */
+
+struct iconv_cspair;
+struct iconv_cspairdata;
+
+/*
+ * iconv converter class definition
+ */
+struct iconv_converter_class {
+	KOBJ_CLASS_FIELDS;
+	TAILQ_ENTRY(iconv_converter_class)	cc_link;
+};
+
+struct iconv_cspair {
+	int		cp_id;		/* unique id of charset pair */
+	int		cp_refcount;	/* number of references from other pairs */
+	const char *	cp_from;
+	const char *	cp_to;
+	void *		cp_data;
+	struct iconv_converter_class * cp_dcp;
+	struct iconv_cspair *cp_base;
+	TAILQ_ENTRY(iconv_cspair)	cp_link;
+};
+
+#define	KICONV_CONVERTER(name,size) 				\
+    static DEFINE_CLASS(iconv_ ## name, iconv_ ## name ## _methods, (size)); \
+    static moduledata_t iconv_ ## name ## _mod = {	\
+	"iconv_"#name, iconv_converter_handler,		\
+	(void*)&iconv_ ## name ## _class		\
+    };							\
+    DECLARE_MODULE(iconv_ ## name, iconv_ ## name ## _mod, SI_SUB_DRIVERS, SI_ORDER_ANY);
+
+#define	KICONV_CES(name,size) 				\
+    static DEFINE_CLASS(iconv_ces_ ## name, iconv_ces_ ## name ## _methods, (size)); \
+    static moduledata_t iconv_ces_ ## name ## _mod = {	\
+	"iconv_ces_"#name, iconv_cesmod_handler,	\
+	(void*)&iconv_ces_ ## name ## _class		\
+    };							\
+    DECLARE_MODULE(iconv_ces_ ## name, iconv_ces_ ## name ## _mod, SI_SUB_DRIVERS, SI_ORDER_ANY);
+
+#ifdef MALLOC_DECLARE
+MALLOC_DECLARE(M_ICONV);
+#endif
+
+/*
+ * Basic conversion functions
+ */
+int iconv_open(const char *to, const char *from, void **handle);
+int iconv_close(void *handle);
+int iconv_conv(void *handle, const char **inbuf,
+	size_t *inbytesleft, char **outbuf, size_t *outbytesleft);
+char* iconv_convstr(void *handle, char *dst, const char *src);
+void* iconv_convmem(void *handle, void *dst, const void *src, int size);
+
+/*
+ * Internal functions
+ */
+int iconv_lookupcp(char **cpp, const char *s);
+
+int iconv_converter_initstub(struct iconv_converter_class *dp);
+int iconv_converter_donestub(struct iconv_converter_class *dp);
+int iconv_converter_handler(module_t mod, int type, void *data);
+
+#ifdef ICONV_DEBUG
+#define ICDEBUG(format, args...) printf("%s: "format, __FUNCTION__ ,## args)
+#else
+#define ICDEBUG(format, args...)
+#endif
+
+#endif /* !_KERNEL */
+
+#endif /* !_SYS_ICONV_H_ */