lxmppd-hg-xmllex: util-src/encodings.c

/* Prosody IM
-- Copyright (C) 2008-2010 Matthew Wild
-- Copyright (C) 2008-2010 Waqas Hussain
-- 
-- This project is MIT/X11 licensed. Please see the
-- COPYING file in the source package for more information.
--
*/
 
/*
* encodings.c
* Lua library for base64, stringprep and idna encodings
*/
 
/* Newer MSVC compilers deprecate strcpy as unsafe, but we use it in a safe way */
#define _CRT_SECURE_NO_DEPRECATE
 
#include <string.h>
#include <stdlib.h>
#include "lua.h"
#include "lauxlib.h"
 
/***************** BASE64 *****************/
 
static const char code[]=
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
 
static void base64_encode(luaL_Buffer *b, unsigned int c1, unsigned int c2, unsigned int c3, int n)
{
	unsigned long tuple=c3+256UL*(c2+256UL*c1);
	int i;
	char s[4];
	for (i=0; i<4; i++) {
		s[3-i] = code[tuple % 64];
		tuple /= 64;
	}
	for (i=n+1; i<4; i++) s[i]='=';
	luaL_addlstring(b,s,4);
}
 
static int Lbase64_encode(lua_State *L)		/** encode(s) */
{
	size_t l;
	const unsigned char *s=(const unsigned char*)luaL_checklstring(L,1,&l);
	luaL_Buffer b;
	int n;
	luaL_buffinit(L,&b);
	for (n=l/3; n--; s+=3) base64_encode(&b,s[0],s[1],s[2],3);
	switch (l%3)
	{
		case 1: base64_encode(&b,s[0],0,0,1);		break;
		case 2: base64_encode(&b,s[0],s[1],0,2);		break;
	}
	luaL_pushresult(&b);
	return 1;
}
 
static void base64_decode(luaL_Buffer *b, int c1, int c2, int c3, int c4, int n)
{
	unsigned long tuple=c4+64L*(c3+64L*(c2+64L*c1));
	char s[3];
	switch (--n)
	{
		case 3: s[2]=(char) tuple;
		case 2: s[1]=(char) (tuple >> 8);
		case 1: s[0]=(char) (tuple >> 16);
	}
	luaL_addlstring(b,s,n);
}
 
static int Lbase64_decode(lua_State *L)		/** decode(s) */
{
	size_t l;
	const char *s=luaL_checklstring(L,1,&l);
	luaL_Buffer b;
	int n=0;
	char t[4];
	luaL_buffinit(L,&b);
	for (;;)
	{
		int c=*s++;
		switch (c)
		{
			const char *p;
			default:
				p=strchr(code,c); if (p==NULL) return 0;
				t[n++]= (char) (p-code);
				if (n==4)
				{
					base64_decode(&b,t[0],t[1],t[2],t[3],4);
					n=0;
				}
				break;
			case '=':
				switch (n)
				{
					case 1: base64_decode(&b,t[0],0,0,0,1);		break;
					case 2: base64_decode(&b,t[0],t[1],0,0,2);	break;
					case 3: base64_decode(&b,t[0],t[1],t[2],0,3);	break;
				}
				n=0;
				break;
			case 0:
				luaL_pushresult(&b);
				return 1;
			case '\n': case '\r': case '\t': case ' ': case '\f': case '\b':
				break;
		}
	}
}
 
static const luaL_Reg Reg_base64[] =
{
	{ "encode",	Lbase64_encode	},
	{ "decode",	Lbase64_decode	},
	{ NULL,		NULL	}
};
 
/***************** STRINGPREP *****************/
#ifndef USE_STRINGPREP_ICU
/****************** libidn ********************/
 
#include <stringprep.h>
 
static int stringprep_prep(lua_State *L, const Stringprep_profile *profile)
{
	size_t len;
	const char *s;
	char string[1024];
	int ret;
	if(!lua_isstring(L, 1)) {
		lua_pushnil(L);
		return 1;
	}
	s = lua_tolstring(L, 1, &len);
	if (len >= 1024) {
		lua_pushnil(L);
		return 1; /* TODO return error message */
	}
	strcpy(string, s);
	ret = stringprep(string, 1024, (Stringprep_profile_flags)0, profile);
	if (ret == STRINGPREP_OK) {
		lua_pushstring(L, string);
		return 1;
	} else {
		lua_pushnil(L);
		return 1; /* TODO return error message */
	}
}
 
#define MAKE_PREP_FUNC(myFunc, prep) \
static int myFunc(lua_State *L) { return stringprep_prep(L, prep); }
 
MAKE_PREP_FUNC(Lstringprep_nameprep, stringprep_nameprep)		/** stringprep.nameprep(s) */
MAKE_PREP_FUNC(Lstringprep_nodeprep, stringprep_xmpp_nodeprep)		/** stringprep.nodeprep(s) */
MAKE_PREP_FUNC(Lstringprep_resourceprep, stringprep_xmpp_resourceprep)		/** stringprep.resourceprep(s) */
MAKE_PREP_FUNC(Lstringprep_saslprep, stringprep_saslprep)		/** stringprep.saslprep(s) */
 
static const luaL_Reg Reg_stringprep[] =
{
	{ "nameprep",	Lstringprep_nameprep	},
	{ "nodeprep",	Lstringprep_nodeprep	},
	{ "resourceprep",	Lstringprep_resourceprep	},
	{ "saslprep",	Lstringprep_saslprep	},
	{ NULL,		NULL	}
};
 
#else
#include <unicode/usprep.h>
#include <unicode/ustring.h>
#include <unicode/utrace.h>
 
static int icu_stringprep_prep(lua_State *L, const UStringPrepProfile *profile)
{
	size_t input_len;
	int32_t unprepped_len, prepped_len, output_len;
	const char *input;
	char output[1024];
 
	UChar unprepped[1024]; /* Temporary unicode buffer (1024 characters) */
	UChar prepped[1024];
	
	UErrorCode err = U_ZERO_ERROR;
 
	if(!lua_isstring(L, 1)) {
		lua_pushnil(L);
		return 1;
	}
	input = lua_tolstring(L, 1, &input_len);
	if (input_len >= 1024) {
		lua_pushnil(L);
		return 1;
	}
	u_strFromUTF8(unprepped, 1024, &unprepped_len, input, input_len, &err);
	prepped_len = usprep_prepare(profile, unprepped, unprepped_len, prepped, 1024, 0, NULL, &err);
	if (U_FAILURE(err)) {
		lua_pushnil(L);
		return 1;
	} else {
		u_strToUTF8(output, 1024, &output_len, prepped, prepped_len, &err);
		if(output_len < 1024)
			lua_pushlstring(L, output, output_len);
		else
			lua_pushnil(L);
		return 1;
	}
}
 
UStringPrepProfile *icu_nameprep;
UStringPrepProfile *icu_nodeprep;
UStringPrepProfile *icu_resourceprep; 
UStringPrepProfile *icu_saslprep;
 
/* initialize global ICU stringprep profiles */
void init_icu()
{
	UErrorCode err = U_ZERO_ERROR;
	utrace_setLevel(UTRACE_VERBOSE);
	icu_nameprep = usprep_openByType(USPREP_RFC3491_NAMEPREP, &err);
	icu_nodeprep = usprep_openByType(USPREP_RFC3920_NODEPREP, &err);
	icu_resourceprep = usprep_openByType(USPREP_RFC3920_RESOURCEPREP, &err);
	icu_saslprep = usprep_openByType(USPREP_RFC4013_SASLPREP, &err);
	if (U_FAILURE(err)) fprintf(stderr, "[c] util.encodings: error: %s\n", u_errorName((UErrorCode)err));
}
 
#define MAKE_PREP_FUNC(myFunc, prep) \
static int myFunc(lua_State *L) { return icu_stringprep_prep(L, prep); }
 
MAKE_PREP_FUNC(Lstringprep_nameprep, icu_nameprep)		/** stringprep.nameprep(s) */
MAKE_PREP_FUNC(Lstringprep_nodeprep, icu_nodeprep)		/** stringprep.nodeprep(s) */
MAKE_PREP_FUNC(Lstringprep_resourceprep, icu_resourceprep)		/** stringprep.resourceprep(s) */
MAKE_PREP_FUNC(Lstringprep_saslprep, icu_saslprep)		/** stringprep.saslprep(s) */
 
static const luaL_Reg Reg_stringprep[] =
{
	{ "nameprep",	Lstringprep_nameprep	},
	{ "nodeprep",	Lstringprep_nodeprep	},
	{ "resourceprep",	Lstringprep_resourceprep	},
	{ "saslprep",	Lstringprep_saslprep	},
	{ NULL,		NULL	}
};
#endif
 
/***************** IDNA *****************/
#ifndef USE_STRINGPREP_ICU
/****************** libidn ********************/
 
#include <idna.h>
#include <idn-free.h>
 
static int Lidna_to_ascii(lua_State *L)		/** idna.to_ascii(s) */
{
	size_t len;
	const char *s = luaL_checklstring(L, 1, &len);
	char* output = NULL;
	int ret = idna_to_ascii_8z(s, &output, IDNA_USE_STD3_ASCII_RULES);
	if (ret == IDNA_SUCCESS) {
		lua_pushstring(L, output);
		idn_free(output);
		return 1;
	} else {
		lua_pushnil(L);
		idn_free(output);
		return 1; /* TODO return error message */
	}
}
 
static int Lidna_to_unicode(lua_State *L)		/** idna.to_unicode(s) */
{
	size_t len;
	const char *s = luaL_checklstring(L, 1, &len);
	char* output = NULL;
	int ret = idna_to_unicode_8z8z(s, &output, 0);
	if (ret == IDNA_SUCCESS) {
		lua_pushstring(L, output);
		idn_free(output);
		return 1;
	} else {
		lua_pushnil(L);
		idn_free(output);
		return 1; /* TODO return error message */
	}
}
#else
#include <unicode/ustdio.h>
#include <unicode/uidna.h>
/* IDNA2003 or IDNA2008 ? ? ? */
static int Lidna_to_ascii(lua_State *L)		/** idna.to_ascii(s) */
{
	size_t len;
	int32_t ulen, dest_len, output_len;
	const char *s = luaL_checklstring(L, 1, &len);
	UChar ustr[1024];
	UErrorCode err = U_ZERO_ERROR;
	UChar dest[1024];
	char output[1024];
 
	u_strFromUTF8(ustr, 1024, &ulen, s, len, &err);
	dest_len = uidna_IDNToASCII(ustr, ulen, dest, 1024, UIDNA_USE_STD3_RULES, NULL, &err);
	if (U_FAILURE(err)) {
		lua_pushnil(L);
		return 1;
	} else {
		u_strToUTF8(output, 1024, &output_len, dest, dest_len, &err);
		if(output_len < 1024)
			lua_pushlstring(L, output, output_len);
		else
			lua_pushnil(L);
		return 1;
	}
}
 
static int Lidna_to_unicode(lua_State *L)		/** idna.to_unicode(s) */
{
	size_t len;
	int32_t ulen, dest_len, output_len;
	const char *s = luaL_checklstring(L, 1, &len);
	UChar* ustr;
	UErrorCode err = U_ZERO_ERROR;
	UChar dest[1024];
	char output[1024];
 
	u_strFromUTF8(ustr, 1024, &ulen, s, len, &err);
	dest_len = uidna_IDNToUnicode(ustr, ulen, dest, 1024, UIDNA_USE_STD3_RULES, NULL, &err);
	if (U_FAILURE(err)) {
		lua_pushnil(L);
		return 1;
	} else {
		u_strToUTF8(output, 1024, &output_len, dest, dest_len, &err);
		if(output_len < 1024)
			lua_pushlstring(L, output, output_len);
		else
			lua_pushnil(L);
		return 1;
	}
}
#endif
 
static const luaL_Reg Reg_idna[] =
{
	{ "to_ascii",	Lidna_to_ascii	},
	{ "to_unicode",	Lidna_to_unicode	},
	{ NULL,		NULL	}
};
 
/***************** end *****************/
 
static const luaL_Reg Reg[] =
{
	{ NULL,		NULL	}
};
 
LUALIB_API int luaopen_util_encodings(lua_State *L)
{
#ifdef USE_STRINGPREP_ICU
	init_icu();
#endif
	luaL_register(L, "encodings", Reg);
 
	lua_pushliteral(L, "base64");
	lua_newtable(L);
	luaL_register(L, NULL, Reg_base64);
	lua_settable(L,-3);
 
	lua_pushliteral(L, "stringprep");
	lua_newtable(L);
	luaL_register(L, NULL, Reg_stringprep);
	lua_settable(L,-3);
 
	lua_pushliteral(L, "idna");
	lua_newtable(L);
	luaL_register(L, NULL, Reg_idna);
	lua_settable(L,-3);
 
	lua_pushliteral(L, "version");			/** version */
	lua_pushliteral(L, "-3.14");
	lua_settable(L,-3);
	return 1;
}

1	/* Prosody IM
2	-- Copyright (C) 2008-2010 Matthew Wild
3	-- Copyright (C) 2008-2010 Waqas Hussain
4	--
5	-- This project is MIT/X11 licensed. Please see the
6	-- COPYING file in the source package for more information.
7	--
8	*/
9
10	/*
11	* encodings.c
12	* Lua library for base64, stringprep and idna encodings
13	*/
14
15	/* Newer MSVC compilers deprecate strcpy as unsafe, but we use it in a safe way */
16	#define _CRT_SECURE_NO_DEPRECATE
17
18	#include <string.h>
19	#include <stdlib.h>
20	#include "lua.h"
21	#include "lauxlib.h"
22
23	/*************** BASE64 ***************/
24
25	static const char code[]=
26	"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
27
28	static void base64_encode(luaL_Buffer *b, unsigned int c1, unsigned int c2, unsigned int c3, int n)
29	{
30	unsigned long tuple=c3+256UL(c2+256ULc1);
31	int i;
32	char s[4];
33	for (i=0; i<4; i++) {
34	s[3-i] = code[tuple % 64];
35	tuple /= 64;
36	}
37	for (i=n+1; i<4; i++) s[i]='=';
38	luaL_addlstring(b,s,4);
39	}
40
41	static int Lbase64_encode(lua_State L) /* encode(s) */
42	{
43	size_t l;
44	const unsigned char s=(const unsigned char)luaL_checklstring(L,1,&l);
45	luaL_Buffer b;
46	int n;
47	luaL_buffinit(L,&b);
48	for (n=l/3; n--; s+=3) base64_encode(&b,s[0],s[1],s[2],3);
49	switch (l%3)
50	{
51	case 1: base64_encode(&b,s[0],0,0,1); break;
52	case 2: base64_encode(&b,s[0],s[1],0,2); break;
53	}
54	luaL_pushresult(&b);
55	return 1;
56	}
57
58	static void base64_decode(luaL_Buffer *b, int c1, int c2, int c3, int c4, int n)
59	{
60	unsigned long tuple=c4+64L(c3+64L(c2+64L*c1));
61	char s[3];
62	switch (--n)
63	{
64	case 3: s[2]=(char) tuple;
65	case 2: s[1]=(char) (tuple >> 8);
66	case 1: s[0]=(char) (tuple >> 16);
67	}
68	luaL_addlstring(b,s,n);
69	}
70
71	static int Lbase64_decode(lua_State L) /* decode(s) */
72	{
73	size_t l;
74	const char *s=luaL_checklstring(L,1,&l);
75	luaL_Buffer b;
76	int n=0;
77	char t[4];
78	luaL_buffinit(L,&b);
79	for (;;)
80	{
81	int c=*s++;
82	switch (c)
83	{
84	const char *p;
85	default:
86	p=strchr(code,c); if (p==NULL) return 0;
87	t[n++]= (char) (p-code);
88	if (n==4)
89	{
90	base64_decode(&b,t[0],t[1],t[2],t[3],4);
91	n=0;
92	}
93	break;
94	case '=':
95	switch (n)
96	{
97	case 1: base64_decode(&b,t[0],0,0,0,1); break;
98	case 2: base64_decode(&b,t[0],t[1],0,0,2); break;
99	case 3: base64_decode(&b,t[0],t[1],t[2],0,3); break;
100	}
101	n=0;
102	break;
103	case 0:
104	luaL_pushresult(&b);
105	return 1;
106	case '\n': case '\r': case '\t': case ' ': case '\f': case '\b':
107	break;
108	}
109	}
110	}
111
112	static const luaL_Reg Reg_base64[] =
113	{
114	{ "encode", Lbase64_encode },
115	{ "decode", Lbase64_decode },
116	{ NULL, NULL }
117	};
118
119	/*************** STRINGPREP ***************/
120	#ifndef USE_STRINGPREP_ICU
121	/**************** libidn ******************/
122
123	#include <stringprep.h>
124
125	static int stringprep_prep(lua_State L, const Stringprep_profile profile)
126	{
127	size_t len;
128	const char *s;
129	char string[1024];
130	int ret;
131	if(!lua_isstring(L, 1)) {
132	lua_pushnil(L);
133	return 1;
134	}
135	s = lua_tolstring(L, 1, &len);
136	if (len >= 1024) {
137	lua_pushnil(L);
138	return 1; /* TODO return error message */
139	}
140	strcpy(string, s);
141	ret = stringprep(string, 1024, (Stringprep_profile_flags)0, profile);
142	if (ret == STRINGPREP_OK) {
143	lua_pushstring(L, string);
144	return 1;
145	} else {
146	lua_pushnil(L);
147	return 1; /* TODO return error message */
148	}
149	}
150
151	#define MAKE_PREP_FUNC(myFunc, prep) \
152	static int myFunc(lua_State *L) { return stringprep_prep(L, prep); }
153
154	MAKE_PREP_FUNC(Lstringprep_nameprep, stringprep_nameprep) /** stringprep.nameprep(s) */
155	MAKE_PREP_FUNC(Lstringprep_nodeprep, stringprep_xmpp_nodeprep) /** stringprep.nodeprep(s) */
156	MAKE_PREP_FUNC(Lstringprep_resourceprep, stringprep_xmpp_resourceprep) /** stringprep.resourceprep(s) */
157	MAKE_PREP_FUNC(Lstringprep_saslprep, stringprep_saslprep) /** stringprep.saslprep(s) */
158
159	static const luaL_Reg Reg_stringprep[] =
160	{
161	{ "nameprep", Lstringprep_nameprep },
162	{ "nodeprep", Lstringprep_nodeprep },
163	{ "resourceprep", Lstringprep_resourceprep },
164	{ "saslprep", Lstringprep_saslprep },
165	{ NULL, NULL }
166	};
167
168	#else
169	#include <unicode/usprep.h>
170	#include <unicode/ustring.h>
171	#include <unicode/utrace.h>
172
173	static int icu_stringprep_prep(lua_State L, const UStringPrepProfile profile)
174	{
175	size_t input_len;
176	int32_t unprepped_len, prepped_len, output_len;
177	const char *input;
178	char output[1024];
179
180	UChar unprepped[1024]; /* Temporary unicode buffer (1024 characters) */
181	UChar prepped[1024];
182
183	UErrorCode err = U_ZERO_ERROR;
184
185	if(!lua_isstring(L, 1)) {
186	lua_pushnil(L);
187	return 1;
188	}
189	input = lua_tolstring(L, 1, &input_len);
190	if (input_len >= 1024) {
191	lua_pushnil(L);
192	return 1;
193	}
194	u_strFromUTF8(unprepped, 1024, &unprepped_len, input, input_len, &err);
195	prepped_len = usprep_prepare(profile, unprepped, unprepped_len, prepped, 1024, 0, NULL, &err);
196	if (U_FAILURE(err)) {
197	lua_pushnil(L);
198	return 1;
199	} else {
200	u_strToUTF8(output, 1024, &output_len, prepped, prepped_len, &err);
201	if(output_len < 1024)
202	lua_pushlstring(L, output, output_len);
203	else
204	lua_pushnil(L);
205	return 1;
206	}
207	}
208
209	UStringPrepProfile *icu_nameprep;
210	UStringPrepProfile *icu_nodeprep;
211	UStringPrepProfile *icu_resourceprep;
212	UStringPrepProfile *icu_saslprep;
213
214	/* initialize global ICU stringprep profiles */
215	void init_icu()
216	{
217	UErrorCode err = U_ZERO_ERROR;
218	utrace_setLevel(UTRACE_VERBOSE);
219	icu_nameprep = usprep_openByType(USPREP_RFC3491_NAMEPREP, &err);
220	icu_nodeprep = usprep_openByType(USPREP_RFC3920_NODEPREP, &err);
221	icu_resourceprep = usprep_openByType(USPREP_RFC3920_RESOURCEPREP, &err);
222	icu_saslprep = usprep_openByType(USPREP_RFC4013_SASLPREP, &err);
223	if (U_FAILURE(err)) fprintf(stderr, "[c] util.encodings: error: %s\n", u_errorName((UErrorCode)err));
224	}
225
226	#define MAKE_PREP_FUNC(myFunc, prep) \
227	static int myFunc(lua_State *L) { return icu_stringprep_prep(L, prep); }
228
229	MAKE_PREP_FUNC(Lstringprep_nameprep, icu_nameprep) /** stringprep.nameprep(s) */
230	MAKE_PREP_FUNC(Lstringprep_nodeprep, icu_nodeprep) /** stringprep.nodeprep(s) */
231	MAKE_PREP_FUNC(Lstringprep_resourceprep, icu_resourceprep) /** stringprep.resourceprep(s) */
232	MAKE_PREP_FUNC(Lstringprep_saslprep, icu_saslprep) /** stringprep.saslprep(s) */
233
234	static const luaL_Reg Reg_stringprep[] =
235	{
236	{ "nameprep", Lstringprep_nameprep },
237	{ "nodeprep", Lstringprep_nodeprep },
238	{ "resourceprep", Lstringprep_resourceprep },
239	{ "saslprep", Lstringprep_saslprep },
240	{ NULL, NULL }
241	};
242	#endif
243
244	/*************** IDNA ***************/
245	#ifndef USE_STRINGPREP_ICU
246	/**************** libidn ******************/
247
248	#include <idna.h>
249	#include <idn-free.h>
250
251	static int Lidna_to_ascii(lua_State L) /* idna.to_ascii(s) */
252	{
253	size_t len;
254	const char *s = luaL_checklstring(L, 1, &len);
255	char* output = NULL;
256	int ret = idna_to_ascii_8z(s, &output, IDNA_USE_STD3_ASCII_RULES);
257	if (ret == IDNA_SUCCESS) {
258	lua_pushstring(L, output);
259	idn_free(output);
260	return 1;
261	} else {
262	lua_pushnil(L);
263	idn_free(output);
264	return 1; /* TODO return error message */
265	}
266	}
267
268	static int Lidna_to_unicode(lua_State L) /* idna.to_unicode(s) */
269	{
270	size_t len;
271	const char *s = luaL_checklstring(L, 1, &len);
272	char* output = NULL;
273	int ret = idna_to_unicode_8z8z(s, &output, 0);
274	if (ret == IDNA_SUCCESS) {
275	lua_pushstring(L, output);
276	idn_free(output);
277	return 1;
278	} else {
279	lua_pushnil(L);
280	idn_free(output);
281	return 1; /* TODO return error message */
282	}
283	}
284	#else
285	#include <unicode/ustdio.h>
286	#include <unicode/uidna.h>
287	/* IDNA2003 or IDNA2008 ? ? ? */
288	static int Lidna_to_ascii(lua_State L) /* idna.to_ascii(s) */
289	{
290	size_t len;
291	int32_t ulen, dest_len, output_len;
292	const char *s = luaL_checklstring(L, 1, &len);
293	UChar ustr[1024];
294	UErrorCode err = U_ZERO_ERROR;
295	UChar dest[1024];
296	char output[1024];
297
298	u_strFromUTF8(ustr, 1024, &ulen, s, len, &err);
299	dest_len = uidna_IDNToASCII(ustr, ulen, dest, 1024, UIDNA_USE_STD3_RULES, NULL, &err);
300	if (U_FAILURE(err)) {
301	lua_pushnil(L);
302	return 1;
303	} else {
304	u_strToUTF8(output, 1024, &output_len, dest, dest_len, &err);
305	if(output_len < 1024)
306	lua_pushlstring(L, output, output_len);
307	else
308	lua_pushnil(L);
309	return 1;
310	}
311	}
312
313	static int Lidna_to_unicode(lua_State L) /* idna.to_unicode(s) */
314	{
315	size_t len;
316	int32_t ulen, dest_len, output_len;
317	const char *s = luaL_checklstring(L, 1, &len);
318	UChar* ustr;
319	UErrorCode err = U_ZERO_ERROR;
320	UChar dest[1024];
321	char output[1024];
322
323	u_strFromUTF8(ustr, 1024, &ulen, s, len, &err);
324	dest_len = uidna_IDNToUnicode(ustr, ulen, dest, 1024, UIDNA_USE_STD3_RULES, NULL, &err);
325	if (U_FAILURE(err)) {
326	lua_pushnil(L);
327	return 1;
328	} else {
329	u_strToUTF8(output, 1024, &output_len, dest, dest_len, &err);
330	if(output_len < 1024)
331	lua_pushlstring(L, output, output_len);
332	else
333	lua_pushnil(L);
334	return 1;
335	}
336	}
337	#endif
338
339	static const luaL_Reg Reg_idna[] =
340	{
341	{ "to_ascii", Lidna_to_ascii },
342	{ "to_unicode", Lidna_to_unicode },
343	{ NULL, NULL }
344	};
345
346	/*************** end ***************/
347
348	static const luaL_Reg Reg[] =
349	{
350	{ NULL, NULL }
351	};
352
353	LUALIB_API int luaopen_util_encodings(lua_State *L)
354	{
355	#ifdef USE_STRINGPREP_ICU
356	init_icu();
357	#endif
358	luaL_register(L, "encodings", Reg);
359
360	lua_pushliteral(L, "base64");
361	lua_newtable(L);
362	luaL_register(L, NULL, Reg_base64);
363	lua_settable(L,-3);
364
365	lua_pushliteral(L, "stringprep");
366	lua_newtable(L);
367	luaL_register(L, NULL, Reg_stringprep);
368	lua_settable(L,-3);
369
370	lua_pushliteral(L, "idna");
371	lua_newtable(L);
372	luaL_register(L, NULL, Reg_idna);
373	lua_settable(L,-3);
374
375	lua_pushliteral(L, "version"); /** version */
376	lua_pushliteral(L, "-3.14");
377	lua_settable(L,-3);
378	return 1;
379	}