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
|
/* Copyright (c) 2003-2018 Dovecot authors, see the included COPYING file */
#include "lib.h"
#include "istream-private.h"
#include "istream-sized.h"
struct sized_istream {
struct istream_private istream;
istream_sized_callback_t *error_callback;
void *error_context;
uoff_t size;
bool min_size_only;
};
static void i_stream_sized_destroy(struct iostream_private *stream)
{
struct sized_istream *sstream =
container_of(stream, struct sized_istream, istream.iostream);
uoff_t v_offset;
v_offset = sstream->istream.parent_start_offset +
sstream->istream.istream.v_offset;
if (sstream->istream.parent->seekable ||
v_offset > sstream->istream.parent->v_offset) {
/* get to same position in parent stream */
i_stream_seek(sstream->istream.parent, v_offset);
}
}
static const char *
i_stream_create_sized_default_error_callback(
const struct istream_sized_error_data *data, void *context ATTR_UNUSED)
{
if (data->v_offset + data->new_bytes < data->wanted_size) {
return t_strdup_printf("Stream is smaller than expected "
"(%"PRIuUOFF_T" < %"PRIuUOFF_T")",
data->v_offset + data->new_bytes, data->wanted_size);
} else {
return t_strdup_printf("Stream is larger than expected "
"(%"PRIuUOFF_T" > %"PRIuUOFF_T", eof=%d)",
data->v_offset + data->new_bytes, data->wanted_size,
data->eof ? 1 : 0);
}
}
static ssize_t
i_stream_sized_parent_read(struct istream_private *stream, size_t *pos_r)
{
ssize_t ret;
do {
ret = i_stream_read_memarea(stream->parent);
stream->istream.stream_errno = stream->parent->stream_errno;
stream->istream.eof = stream->parent->eof;
stream->buffer = i_stream_get_data(stream->parent, pos_r);
} while (*pos_r <= stream->pos && ret > 0);
return ret;
}
static ssize_t i_stream_sized_read(struct istream_private *stream)
{
struct sized_istream *sstream =
container_of(stream, struct sized_istream, istream);
struct istream_sized_error_data data;
const char *error;
uoff_t left;
ssize_t ret;
size_t pos;
i_stream_seek(stream->parent, sstream->istream.parent_start_offset +
stream->istream.v_offset);
stream->pos -= stream->skip;
stream->skip = 0;
stream->buffer = i_stream_get_data(stream->parent, &pos);
if (pos > stream->pos)
ret = 0;
else {
if ((ret = i_stream_sized_parent_read(stream, &pos)) == -2)
return -2;
}
left = sstream->size - stream->istream.v_offset;
if (pos == left && ret != -1) {
/* we have exactly the wanted amount of data left, but we
don't know yet if there is more data in parent. */
ret = i_stream_sized_parent_read(stream, &pos);
}
i_zero(&data);
data.v_offset = stream->istream.v_offset;
data.new_bytes = pos;
data.wanted_size = sstream->size;
data.eof = stream->istream.eof;
if (pos == left) {
/* we may or may not be finished, depending on whether
parent is at EOF. */
} else if (pos > left) {
/* parent has more data available than expected */
if (!sstream->min_size_only) {
error = sstream->error_callback(&data, sstream->error_context);
io_stream_set_error(&stream->iostream, "%s", error);
stream->istream.stream_errno = EINVAL;
return -1;
}
pos = left;
if (pos <= stream->pos) {
stream->istream.eof = TRUE;
ret = -1;
}
} else if (!stream->istream.eof) {
/* still more to read */
} else if (stream->istream.stream_errno == ENOENT) {
/* lost the file */
} else {
/* EOF before we reached the wanted size */
error = sstream->error_callback(&data, sstream->error_context);
io_stream_set_error(&stream->iostream, "%s", error);
stream->istream.stream_errno = EPIPE;
}
ret = pos > stream->pos ? (ssize_t)(pos - stream->pos) :
(ret == 0 ? 0 : -1);
stream->pos = pos;
i_assert(ret != -1 || stream->istream.eof ||
stream->istream.stream_errno != 0);
return ret;
}
static int
i_stream_sized_stat(struct istream_private *stream, bool exact ATTR_UNUSED)
{
struct sized_istream *sstream =
container_of(stream, struct sized_istream, istream);
const struct stat *st;
/* parent stream may be base64-decoder. don't waste time decoding the
entire stream, since we already know what the size is supposed
to be. */
if (i_stream_stat(stream->parent, FALSE, &st) < 0) {
stream->istream.stream_errno = stream->parent->stream_errno;
return -1;
}
stream->statbuf = *st;
stream->statbuf.st_size = sstream->size;
return 0;
}
static struct sized_istream *
i_stream_create_sized_common(struct istream *input, uoff_t size)
{
struct sized_istream *sstream;
sstream = i_new(struct sized_istream, 1);
sstream->size = size;
sstream->istream.max_buffer_size = input->real_stream->max_buffer_size;
sstream->istream.iostream.destroy = i_stream_sized_destroy;
sstream->istream.read = i_stream_sized_read;
sstream->istream.stat = i_stream_sized_stat;
sstream->istream.istream.readable_fd = input->readable_fd;
sstream->istream.istream.blocking = input->blocking;
sstream->istream.istream.seekable = input->seekable;
(void)i_stream_create(&sstream->istream, input,
i_stream_get_fd(input), 0);
return sstream;
}
struct istream *i_stream_create_sized(struct istream *input, uoff_t size)
{
struct sized_istream *sstream;
sstream = i_stream_create_sized_common(input, size);
sstream->error_callback = i_stream_create_sized_default_error_callback;
sstream->error_context = sstream;
return &sstream->istream.istream;
}
struct istream *i_stream_create_sized_range(struct istream *input,
uoff_t offset, uoff_t size)
{
uoff_t orig_offset = input->v_offset;
struct istream *ret;
input->v_offset = offset;
ret = i_stream_create_sized(input, size);
input->v_offset = orig_offset;
return ret;
}
struct istream *i_stream_create_min_sized(struct istream *input, uoff_t min_size)
{
struct istream *ret;
ret= i_stream_create_sized(input, min_size);
struct sized_istream *ret_sstream =
container_of(ret->real_stream, struct sized_istream, istream);
ret_sstream->min_size_only = TRUE;
return ret;
}
struct istream *i_stream_create_min_sized_range(struct istream *input,
uoff_t offset, uoff_t min_size)
{
struct istream *ret;
ret = i_stream_create_sized_range(input, offset, min_size);
struct sized_istream *ret_sstream =
container_of(ret->real_stream, struct sized_istream, istream);
ret_sstream->min_size_only = TRUE;
return ret;
}
#undef i_stream_create_sized_with_callback
struct istream *
i_stream_create_sized_with_callback(struct istream *input, uoff_t size,
istream_sized_callback_t *error_callback,
void *context)
{
struct sized_istream *sstream;
sstream = i_stream_create_sized_common(input, size);
sstream->error_callback = error_callback;
sstream->error_context = context;
return &sstream->istream.istream;
}
|
