1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
|
/*
* Copyright 2009 by Marco d'Itri <md@linux.it>.
*
* simple_recode was inspired by a similar function found in Simon
* Josefsson's libidn.
*
* 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 <stdlib.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <iconv.h>
#include <langinfo.h>
#include "utils.h"
#include "simple_recode.h"
/* Global variables */
iconv_t simple_recode_iconv_handle;
const char *simple_recode_input_charset;
/*
* These value should be tuned to an acceptable compromise between memory
* usage and calling iconv(3) as few times as possible.
*/
#define SIMPLE_RECODE_BUFFER_SIZE_1 256
#define SIMPLE_RECODE_BUFFER_SIZE_2 1024
#define SIMPLE_RECODE_BUFFER_INCREMENT 1
/*
* Convert a NULL-terminated string accordingly to the provided iconv(3)
* handle. The returned string is allocated using malloc(3) and needs to be
* deallocated by the caller.
* Incomplete, invalid and impossible to recode sequences are copied as-is.
* On failure, NULL is returned and errno is set.
*/
char *simple_recode(const iconv_t handle, const char *str)
{
char *inp = (char *) str;
char *outp, *result;
size_t inbytes_remaining, outbytes_remaining, outbuf_size;
inbytes_remaining = strlen(inp);
if (inbytes_remaining + 1 <= SIMPLE_RECODE_BUFFER_SIZE_1
- (SIMPLE_RECODE_BUFFER_SIZE_1 >> SIMPLE_RECODE_BUFFER_INCREMENT))
outbuf_size = SIMPLE_RECODE_BUFFER_SIZE_1;
else
outbuf_size = inbytes_remaining + 1
+ (inbytes_remaining >> SIMPLE_RECODE_BUFFER_INCREMENT);
outp = result = malloc(outbuf_size);
if (!result)
return NULL;
outbytes_remaining = outbuf_size - 1;
do {
size_t err = iconv(handle, &inp, &inbytes_remaining, &outp,
&outbytes_remaining);
if (err != -1)
break; /* success */
switch (errno) {
case EINVAL: /* incomplete multibyte sequence */
case EILSEQ: /* invalid multibyte sequence */
#ifdef SIMPLE_RECODE_SKIP_INVALID_SEQUENCES
/* recover from invalid input by replacing it with a '?' */
inp++;
*outp++ = '?'; /* use U+FFFD for unicode output? how? */
#else
/* garbage in, garbage out */
*outp++ = *inp++;
#endif
inbytes_remaining--;
outbytes_remaining--;
continue;
case E2BIG:
{
size_t used = outp - result;
size_t newsize;
if (outbuf_size < SIMPLE_RECODE_BUFFER_SIZE_2)
newsize = SIMPLE_RECODE_BUFFER_SIZE_2;
else
newsize = outbuf_size
+ (outbuf_size >> SIMPLE_RECODE_BUFFER_INCREMENT);
/* check if the newsize variable has overflowed */
if (newsize <= outbuf_size) {
errno = ENOMEM;
return NULL;
}
outbuf_size = newsize;
result = realloc(result, outbuf_size);
if (!result)
return NULL;
/* update the position in the new output stream */
outp = result + used;
outbytes_remaining = outbuf_size - used - 1;
continue;
}
default:
return NULL;
}
} while (inbytes_remaining > 0);
*outp = '\0';
return result;
}
/*
* Like fputs(3), but transparently recodes s using the global variable
* simple_recode_input_charset as the input charset and the current locale
* as the output charset.
* If simple_recode_input_charset is NULL it just calls fputs(3).
* Exits with an error if iconv(3) or iconv_open(3) fail.
*
* Assumes that setlocale(3) has already been called.
*
* If appropriate, the iconv object referenced by the global variable
* simple_recode_iconv_handle should be deallocated with iconv_close(3).
*/
int recode_fputs(const char *s, FILE *stream)
{
char *out;
int result;
if (simple_recode_input_charset == NULL) /* no conversion is needed */
return fputs(s, stream);
if (simple_recode_iconv_handle == NULL) {
simple_recode_iconv_handle = iconv_open(nl_langinfo(CODESET),
simple_recode_input_charset);
if (simple_recode_iconv_handle == (iconv_t) - 1)
err_sys("iconv_open");
}
out = simple_recode(simple_recode_iconv_handle, s);
if (!out)
err_sys("iconv");
result = fputs(out, stream);
free(out);
return result;
}
void simple_recode_iconv_close(void)
{
if (simple_recode_iconv_handle == NULL)
return;
iconv_close(simple_recode_iconv_handle);
simple_recode_iconv_handle = NULL;
simple_recode_input_charset = NULL;
}
|
