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
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
|
/*
* %CopyrightBegin%
*
* Copyright Ericsson AB 1998-2018. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* %CopyrightEnd%
*/
#include <string.h>
#include "eidef.h"
#include "eiext.h"
#include "putget.h"
int ei_decode_atom(const char *buf, int *index, char *p)
{
return ei_decode_atom_as(buf, index, p, MAXATOMLEN, ERLANG_LATIN1, NULL, NULL);
}
int ei_decode_atom_as(const char *buf, int *index, char* p, int destlen,
erlang_char_encoding want_enc,
erlang_char_encoding* was_encp,
erlang_char_encoding* res_encp)
{
const char *s = buf + *index;
const char *s0 = s;
int len;
erlang_char_encoding got_enc;
switch (get8(s)) {
case ERL_ATOM_EXT:
len = get16be(s);
got_enc = ERLANG_LATIN1;
break;
case ERL_SMALL_ATOM_EXT:
len = get8(s);
got_enc = ERLANG_LATIN1;
break;
case ERL_ATOM_UTF8_EXT:
len = get16be(s);
got_enc = ERLANG_UTF8;
break;
case ERL_SMALL_ATOM_UTF8_EXT:
len = get8(s);
got_enc = ERLANG_UTF8;
break;
default:
return -1;
}
if ((want_enc & got_enc) || want_enc == ERLANG_ASCII) {
int i, found_non_ascii = 0;
if (len >= destlen)
return -1;
for (i=0; i<len; i++) {
if (s[i] & 0x80) found_non_ascii = 1;
if (p) p[i] = s[i];
}
if (p) p[len] = 0;
if (want_enc == ERLANG_ASCII && found_non_ascii) {
return -1;
}
if (res_encp) {
*res_encp = found_non_ascii ? got_enc : ERLANG_ASCII;
}
}
else {
int plen = (got_enc == ERLANG_LATIN1) ?
latin1_to_utf8(p, s, len, destlen-1, res_encp) :
utf8_to_latin1(p, s, len, destlen-1, res_encp);
if (plen < 0) return -1;
if (p) p[plen] = 0;
}
if (was_encp) {
*was_encp = got_enc;
}
s += len;
*index += s-s0;
return 0;
}
#ifdef HAVE_UNALIGNED_WORD_ACCESS
#if SIZEOF_VOID_P == SIZEOF_LONG
typedef unsigned long AsciiWord;
#elif SIZEOF_VOID_P == SIZEOF_LONG_LONG
typedef unsigned long long AsciiWord;
#else
# error "Uknown word type"
#endif
#if SIZEOF_VOID_P == 4
# define ASCII_CHECK_MASK ((AsciiWord)0x80808080U)
#elif SIZEOF_VOID_P == 8
# define ASCII_CHECK_MASK ((AsciiWord)0x8080808080808080U)
#endif
static int ascii_fast_track(char* dst, const char* src, int slen, int destlen)
{
const AsciiWord* src_word = (AsciiWord*) src;
const AsciiWord* const src_word_end = src_word + (slen / sizeof(AsciiWord));
if (destlen < slen)
return 0;
if (dst) {
AsciiWord* dst_word = (AsciiWord*)dst;
while (src_word < src_word_end) {
if ((*src_word & ASCII_CHECK_MASK) != 0)
break;
*dst_word++ = *src_word++;
}
}
else {
while (src_word < src_word_end) {
if ((*src_word & ASCII_CHECK_MASK) != 0)
break;
src_word++;
}
}
return (char*)src_word - src;
}
#endif /* HAVE_UNALIGNED_WORD_ACCESS */
int utf8_to_latin1(char* dst, const char* src, int slen, int destlen,
erlang_char_encoding* res_encp)
{
const char* const dst_start = dst;
const char* const dst_end = dst + destlen;
int found_non_ascii = 0;
#ifdef HAVE_UNALIGNED_WORD_ACCESS
{
int aft = ascii_fast_track(dst, src, slen, destlen);
src += aft;
slen -= aft;
dst += aft;
}
#endif
while (slen > 0) {
if (dst >= dst_end) return -1;
if ((src[0] & 0x80) == 0) {
if (dst_start) {
*dst = *src;
}
++dst;
++src;
--slen;
}
else if (slen > 1 &&
(src[0] & 0xFE) == 0xC2 &&
(src[1] & 0xC0) == 0x80) {
if (dst_start) {
*dst = (char) ((src[0] << 6) | (src[1] & 0x3F));
}
++dst;
src += 2;
slen -= 2;
found_non_ascii = 1;
}
else return -1;
}
if (res_encp) {
*res_encp = found_non_ascii ? ERLANG_LATIN1 : ERLANG_ASCII;
}
return dst - dst_start;
}
int latin1_to_utf8(char* dst, const char* src, int slen, int destlen,
erlang_char_encoding* res_encp)
{
const char* const src_end = src + slen;
const char* const dst_start = dst;
const char* const dst_end = dst + destlen;
int found_non_ascii = 0;
#ifdef HAVE_UNALIGNED_WORD_ACCESS
{
int aft = ascii_fast_track(dst, src, slen, destlen);
dst += aft;
src += aft;
}
#endif
while (src < src_end) {
if (dst >= dst_end) return -1;
if ((src[0] & 0x80) == 0) {
if (dst_start) {
*dst = *src;
}
++dst;
}
else {
if (dst_start) {
unsigned char ch = *src;
dst[0] = 0xC0 | (ch >> 6);
dst[1] = 0x80 | (ch & 0x3F);
}
dst += 2;
found_non_ascii = 1;
}
++src;
}
if (res_encp) {
*res_encp = found_non_ascii ? ERLANG_UTF8 : ERLANG_ASCII;
}
return dst - dst_start;
}
int ei_internal_get_atom(const char** bufp, char* p,
erlang_char_encoding* was_encp)
{
int ix = 0;
if (ei_decode_atom_as(*bufp, &ix, p, MAXATOMLEN_UTF8, ERLANG_UTF8, was_encp, NULL) < 0)
return -1;
*bufp += ix;
return 0;
}
|
