1 /* Copyright (c) 2014-2018 Dovecot authors, see the included COPYING file */
2
3 #include "lib.h"
4 #include "fdpass.h"
5 #include "istream-file-private.h"
6 #include "istream-unix.h"
7
8 struct unix_istream {
9 struct file_istream fstream;
10 bool next_read_fd;
11 int read_fd;
12 };
13
14 static void
i_stream_unix_close(struct iostream_private * stream,bool close_parent)15 i_stream_unix_close(struct iostream_private *stream, bool close_parent)
16 {
17 struct unix_istream *ustream =
18 container_of(stream, struct unix_istream,
19 fstream.istream.iostream);
20
21 i_close_fd(&ustream->read_fd);
22 i_stream_file_close(stream, close_parent);
23 }
24
i_stream_unix_read(struct istream_private * stream)25 static ssize_t i_stream_unix_read(struct istream_private *stream)
26 {
27 struct unix_istream *ustream =
28 container_of(stream, struct unix_istream, fstream.istream);
29 size_t size;
30 ssize_t ret;
31
32 if (!ustream->next_read_fd)
33 return i_stream_file_read(stream);
34
35 i_assert(ustream->read_fd == -1);
36 i_assert(ustream->fstream.skip_left == 0); /* not supported here.. */
37 if (!i_stream_try_alloc(stream, 1, &size))
38 return -2;
39
40 ret = fd_read(stream->fd, stream->w_buffer + stream->pos, size,
41 &ustream->read_fd);
42 if (ustream->read_fd != -1)
43 ustream->next_read_fd = FALSE;
44
45 if (ret == 0) {
46 /* EOF */
47 stream->istream.eof = TRUE;
48 ustream->fstream.seen_eof = TRUE;
49 return -1;
50 }
51
52 if (unlikely(ret < 0)) {
53 if ((errno == EINTR || errno == EAGAIN) &&
54 !stream->istream.blocking) {
55 return 0;
56 } else {
57 i_assert(errno != 0);
58 /* if we get EBADF for a valid fd, it means something's
59 really wrong and we'd better just crash. */
60 i_assert(errno != EBADF);
61 stream->istream.stream_errno = errno;
62 return -1;
63 }
64 }
65 stream->pos += ret;
66 return ret;
67 }
68
i_stream_create_unix(int fd,size_t max_buffer_size)69 struct istream *i_stream_create_unix(int fd, size_t max_buffer_size)
70 {
71 struct unix_istream *ustream;
72 struct istream *input;
73
74 i_assert(fd != -1);
75
76 ustream = i_new(struct unix_istream, 1);
77 ustream->read_fd = -1;
78 input = i_stream_create_file_common(&ustream->fstream, fd, NULL,
79 max_buffer_size, FALSE);
80 input->real_stream->iostream.close = i_stream_unix_close;
81 input->real_stream->read = i_stream_unix_read;
82 return input;
83 }
84
i_stream_unix_set_read_fd(struct istream * input)85 void i_stream_unix_set_read_fd(struct istream *input)
86 {
87 struct unix_istream *ustream =
88 container_of(input->real_stream, struct unix_istream,
89 fstream.istream);
90
91 ustream->next_read_fd = TRUE;
92 }
93
i_stream_unix_unset_read_fd(struct istream * input)94 void i_stream_unix_unset_read_fd(struct istream *input)
95 {
96 struct unix_istream *ustream =
97 container_of(input->real_stream, struct unix_istream,
98 fstream.istream);
99
100 ustream->next_read_fd = FALSE;
101 }
102
i_stream_unix_get_read_fd(struct istream * input)103 int i_stream_unix_get_read_fd(struct istream *input)
104 {
105 struct unix_istream *ustream =
106 container_of(input->real_stream, struct unix_istream,
107 fstream.istream);
108 int fd;
109
110 fd = ustream->read_fd;
111 ustream->read_fd = -1;
112 return fd;
113 }
114