1 /*
2 * ngIRCd -- The Next Generation IRC Daemon
3 * Copyright (c)2001-2014 Alexander Barton (alex@barton.de) and Contributors.
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 * Please read the file COPYING, README and AUTHORS for more information.
10 */
11
12 #define __conn_encoding_c__
13
14 #define CONN_MODULE
15
16 #include "portab.h"
17
18 /**
19 * @file
20 * Functions to deal with character encodings and conversions
21 */
22
23 #include <assert.h>
24 #include <stdio.h>
25 #include <string.h>
26 #include <strings.h>
27
28 #include "conn.h"
29
30 #ifdef ICONV
31
32 #include "log.h"
33 #include "conn-encoding.h"
34
35 char Encoding_Buffer[COMMAND_LEN];
36 char *Convert_Message PARAMS((iconv_t Handle, char *Message));
37
38 /**
39 * Set client character encoding on a connection.
40 *
41 * @param Conn Connection identifier.
42 * @param ClientEnc Client encoding (for example "ASCII", "MacRoman", ...).
43 * @return true on success, false otherwise.
44 */
45 GLOBAL bool
Conn_SetEncoding(CONN_ID Conn,const char * ClientEnc)46 Conn_SetEncoding(CONN_ID Conn, const char *ClientEnc)
47 {
48 char client_enc[25], server_enc[25];
49
50 assert(Conn > NONE);
51 assert(ClientEnc != NULL);
52
53 Conn_UnsetEncoding(Conn);
54
55 /* Is the client character set identical to server character set? */
56 if (strcasecmp(ClientEnc, "UTF-8") == 0)
57 return true;
58
59 snprintf(client_enc, sizeof(client_enc), "%s//TRANSLIT", ClientEnc);
60 snprintf(server_enc, sizeof(server_enc), "%s//TRANSLIT", "UTF-8");
61
62 My_Connections[Conn].iconv_from = iconv_open(server_enc, client_enc);
63 if (My_Connections[Conn].iconv_from == (iconv_t)(-1)) {
64 Conn_UnsetEncoding(Conn);
65 return false;
66 }
67 My_Connections[Conn].iconv_to = iconv_open(client_enc, server_enc);
68 if (My_Connections[Conn].iconv_to == (iconv_t)(-1)) {
69 Conn_UnsetEncoding(Conn);
70 return false;
71 }
72
73 LogDebug("Set client character set of connection \"%d\" to \"%s\".",
74 Conn, client_enc);
75 return true;
76 }
77
78 /**
79 * Remove client character encoding conversion on a connection.
80 *
81 * @param Conn Connection identifier.
82 */
83 GLOBAL void
Conn_UnsetEncoding(CONN_ID Conn)84 Conn_UnsetEncoding(CONN_ID Conn)
85 {
86 assert(Conn > NONE);
87
88 if (My_Connections[Conn].iconv_from != (iconv_t)(-1))
89 iconv_close(My_Connections[Conn].iconv_from);
90 if (My_Connections[Conn].iconv_to != (iconv_t)(-1))
91 iconv_close(My_Connections[Conn].iconv_to);
92
93 My_Connections[Conn].iconv_from = (iconv_t)(-1);
94 My_Connections[Conn].iconv_to = (iconv_t)(-1);
95
96 LogDebug("Unset character conversion of connection %d.", Conn);
97 }
98
99 /**
100 * Convert the encoding of a given message.
101 *
102 * This function uses a static buffer for the result of the encoding
103 * conversion which is overwritten by subsequent calls to this function!
104 *
105 * @param Handle libiconv handle.
106 * @param Message The message to convert.
107 * @return Pointer to the result.
108 */
109 char *
Convert_Message(iconv_t Handle,char * Message)110 Convert_Message(iconv_t Handle, char *Message)
111 {
112 size_t in_left, out_left;
113 char *out = Encoding_Buffer;
114
115 assert (Handle != (iconv_t)(-1));
116 assert (Message != NULL);
117
118 in_left = strlen(Message);
119 out_left = sizeof(Encoding_Buffer) - 1;
120
121 if (iconv(Handle, &Message, &in_left, &out, &out_left) == (size_t)(-1)) {
122 /* An error occurred! */
123 LogDebug("Error converting message encoding!");
124 strlcpy(out, Message, sizeof(Encoding_Buffer));
125 iconv(Handle, NULL, NULL, NULL, NULL);
126 } else
127 *out = '\0';
128
129 return Encoding_Buffer;
130 }
131
132 #endif /* ICONV */
133
134 /**
135 * Convert encoding of a message received from a connection.
136 *
137 * Note 1: If no conversion is required, this function returns the original
138 * pointer to the message.
139 *
140 * Note 2: This function uses Convert_Message(), so subsequent calls to this
141 * function will overwrite the earlier results.
142 *
143 * @param Conn Connection identifier.
144 * @param Message The message to convert.
145 * @return Pointer to the result.
146 * @see Convert_Message
147 */
148 GLOBAL char *
Conn_EncodingFrom(UNUSED CONN_ID Conn,char * Message)149 Conn_EncodingFrom(UNUSED CONN_ID Conn, char *Message)
150 {
151 assert(Conn > NONE);
152 assert (Message != NULL);
153
154 #ifdef ICONV
155 if (My_Connections[Conn].iconv_from != (iconv_t)(-1))
156 return Convert_Message(My_Connections[Conn].iconv_from, Message);
157 #endif
158 return Message;
159 }
160
161 /**
162 * Convert encoding of a message for sending on a connection.
163 *
164 * Note 1: If no conversion is required, this function returns the original
165 * pointer to the message.
166 *
167 * Note 2: This function uses Convert_Message(), so subsequent calls to this
168 * function will overwrite the earlier results.
169 *
170 * @param Conn Connection identifier.
171 * @param Message The message to convert.
172 * @return Pointer to the result.
173 * @see Convert_Message
174 */
175 GLOBAL char *
Conn_EncodingTo(UNUSED CONN_ID Conn,char * Message)176 Conn_EncodingTo(UNUSED CONN_ID Conn, char *Message)
177 {
178 assert(Conn > NONE);
179 assert (Message != NULL);
180
181 #ifdef ICONV
182 if (My_Connections[Conn].iconv_to != (iconv_t)(-1))
183 return Convert_Message(My_Connections[Conn].iconv_to, Message);
184 #endif
185 return Message;
186 }
187
188 /* -eof- */
189