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
|
/*
Unix SMB/CIFS implementation.
Copyright (C) Stefan Metzmacher 2009
** NOTE! The following LGPL license applies to the tevent
** library. This does NOT imply that all of Samba is released
** under the LGPL
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 3 of the License, or (at your option) any later version.
This library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "replace.h"
#include "system/network.h"
#include "tsocket.h"
#include "tsocket_internal.h"
struct tsocket_readv_state {
/* this structs are owned by the caller */
struct {
struct tsocket_context *sock;
tsocket_readv_next_iovec_t next_iovec_fn;
void *private_data;
} caller;
/*
* Each call to the callback resets iov and count
* the callback allocated the iov as child of our state,
* that means we are allowed to modify and free it.
*
* we should call the callback every time we filled the given
* vector and ask for a new vector. We return if the callback
* ask for 0 bytes.
*/
struct iovec *iov;
size_t count;
/*
* the total number of bytes we read,
* the return value of the _recv function
*/
int total_read;
};
static int tsocket_readv_state_destructor(struct tsocket_readv_state *state)
{
if (state->caller.sock) {
tsocket_set_readable_handler(state->caller.sock, NULL, NULL);
}
ZERO_STRUCT(state->caller);
return 0;
}
static bool tsocket_readv_ask_for_next_vector(struct tevent_req *req,
struct tsocket_readv_state *state)
{
int ret;
int err;
bool dummy;
size_t to_read = 0;
size_t i;
talloc_free(state->iov);
state->iov = NULL;
state->count = 0;
ret = state->caller.next_iovec_fn(state->caller.sock,
state->caller.private_data,
state, &state->iov, &state->count);
err = tsocket_error_from_errno(ret, errno, &dummy);
if (tevent_req_error(req, err)) {
return false;
}
for (i=0; i < state->count; i++) {
size_t tmp = to_read;
tmp += state->iov[i].iov_len;
if (tmp < to_read) {
tevent_req_error(req, EMSGSIZE);
return false;
}
to_read = tmp;
}
if (to_read == 0) {
tevent_req_done(req);
return false;
}
if (state->total_read + to_read < state->total_read) {
tevent_req_error(req, EMSGSIZE);
return false;
}
return true;
}
static void tsocket_readv_handler(struct tsocket_context *sock,
void *private_data);
struct tevent_req *tsocket_readv_send(struct tsocket_context *sock,
TALLOC_CTX *mem_ctx,
tsocket_readv_next_iovec_t next_iovec_fn,
void *private_data)
{
struct tevent_req *req;
struct tsocket_readv_state *state;
int ret;
int err;
bool dummy;
req = tevent_req_create(mem_ctx, &state,
struct tsocket_readv_state);
if (!req) {
return NULL;
}
state->caller.sock = sock;
state->caller.next_iovec_fn = next_iovec_fn;
state->caller.private_data = private_data;
state->iov = NULL;
state->count = 0;
state->total_read = 0;
if (!tsocket_readv_ask_for_next_vector(req, state)) {
goto post;
}
talloc_set_destructor(state, tsocket_readv_state_destructor);
ret = tsocket_set_readable_handler(sock,
tsocket_readv_handler,
req);
err = tsocket_error_from_errno(ret, errno, &dummy);
if (tevent_req_error(req, err)) {
goto post;
}
return req;
post:
return tevent_req_post(req, sock->event.ctx);
}
static void tsocket_readv_handler(struct tsocket_context *sock,
void *private_data)
{
struct tevent_req *req = talloc_get_type(private_data,
struct tevent_req);
struct tsocket_readv_state *state = tevent_req_data(req,
struct tsocket_readv_state);
ssize_t ret;
int err;
bool retry;
ret = tsocket_readv(state->caller.sock,
state->iov,
state->count);
err = tsocket_error_from_errno(ret, errno, &retry);
if (retry) {
/* retry later */
return;
}
if (tevent_req_error(req, err)) {
return;
}
state->total_read += ret;
while (ret > 0) {
if (ret < state->iov[0].iov_len) {
uint8_t *base;
base = (uint8_t *)state->iov[0].iov_base;
base += ret;
state->iov[0].iov_base = base;
state->iov[0].iov_len -= ret;
break;
}
ret -= state->iov[0].iov_len;
state->iov += 1;
state->count -= 1;
}
if (state->count) {
/* we have more to read */
return;
}
/* ask the callback for a new vector we should fill */
tsocket_readv_ask_for_next_vector(req, state);
}
int tsocket_readv_recv(struct tevent_req *req, int *perrno)
{
struct tsocket_readv_state *state = tevent_req_data(req,
struct tsocket_readv_state);
int ret;
ret = tsocket_simple_int_recv(req, perrno);
if (ret == 0) {
ret = state->total_read;
}
tevent_req_received(req);
return ret;
}
|
