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
|
/*
Unix SMB/Netbios implementation.
Version 3.2.x
recvfile implementations.
Copyright (C) Jeremy Allison 2007.
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 3 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, see <http://www.gnu.org/licenses/>.
*/
/*
* This file handles the OS dependent recvfile implementations.
* The API is such that it returns -1 on error, else returns the
* number of bytes written.
*/
#include "includes.h"
/* Do this on our own in TRANSFER_BUF_SIZE chunks.
* It's safe to make direct syscalls to lseek/write here
* as we're below the Samba vfs layer.
*
* If tofd is -1 we just drain the incoming socket of count
* bytes without writing to the outgoing fd.
* If a write fails we do the same (to cope with disk full)
* errors.
*
* Returns -1 on short reads from fromfd (read error)
* and sets errno.
*
* Returns number of bytes written to 'tofd'
* or thrown away if 'tofd == -1'.
* eturn != count then sets errno.
* Returns count if complete success.
*/
#ifndef TRANSFER_BUF_SIZE
#define TRANSFER_BUF_SIZE (128*1024)
#endif
static ssize_t default_sys_recvfile(int fromfd,
int tofd,
SMB_OFF_T offset,
size_t count)
{
int saved_errno = 0;
size_t total = 0;
size_t bufsize = MIN(TRANSFER_BUF_SIZE,count);
size_t total_written = 0;
char *buffer = NULL;
if (count == 0) {
return 0;
}
if (tofd != -1 && offset != (SMB_OFF_T)-1) {
if (sys_lseek(tofd, offset, SEEK_SET) == -1) {
if (errno != ESPIPE) {
return -1;
}
}
}
buffer = SMB_MALLOC_ARRAY(char, bufsize);
if (buffer == NULL) {
return -1;
}
while (total < count) {
size_t num_written = 0;
ssize_t read_ret;
size_t toread = MIN(bufsize,count - total);
/* Read from socket - ignore EINTR. */
read_ret = sys_read(fromfd, buffer, toread);
if (read_ret <= 0) {
/* EOF or socket error. */
free(buffer);
return -1;
}
num_written = 0;
while (num_written < read_ret) {
ssize_t write_ret;
if (tofd == -1) {
write_ret = read_ret;
} else {
/* Write to file - ignore EINTR. */
write_ret = sys_write(tofd,
buffer + num_written,
read_ret - num_written);
if (write_ret <= 0) {
/* write error - stop writing. */
tofd = -1;
saved_errno = errno;
continue;
}
}
num_written += (size_t)write_ret;
total_written += (size_t)write_ret;
}
total += read_ret;
}
free(buffer);
if (saved_errno) {
/* Return the correct write error. */
errno = saved_errno;
}
return (ssize_t)total_written;
}
#if defined(HAVE_SPLICE_SYSCALL)
#ifdef JRA_SPLICE_TEST
#include <linux/unistd.h>
#include <sys/syscall.h>
#define __NR_splice 313
_syscall6( long, splice,
int, fromfd,
loff_t *, fromoffset,
int, tofd,
loff_t *, tooffset,
size_t, count,
unsigned int, flags);
#endif
ssize_t sys_recvfile(int fromfd,
int tofd,
SMB_OFF_T offset,
size_t count)
{
size_t total = 0;
if (count == 0) {
return 0;
}
while (total < count) {
ssize_t ret = splice(fromfd,
NULL,
tofd,
&offset,
count,
0);
if (ret == -1) {
if (errno != EINTR) {
return -1;
}
continue;
}
total += ret;
count -= ret;
}
return total;
}
#else
/*****************************************************************
No recvfile system call - use the default 128 chunk implementation.
*****************************************************************/
ssize_t sys_recvfile(int fromfd,
int tofd,
SMB_OFF_T offset,
size_t count)
{
return default_sys_recvfile(fromfd, tofd, offset, count);
}
#endif
/*****************************************************************
Throw away "count" bytes from the client socket.
*****************************************************************/
ssize_t drain_socket(int sockfd, size_t count)
{
return default_sys_recvfile(sockfd, -1, (SMB_OFF_T)-1, count);
}
|
