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
|
/* Copyright (c) 2018, Curtis McEnroe <programble@gmail.com>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <sys/types.h>
#include <err.h>
#include <fcntl.h>
#include <poll.h>
#include <signal.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/event.h>
#include <sys/ioctl.h>
#include <sysexits.h>
#include <termios.h>
#include <unistd.h>
static struct termios saveTerm;
static void restoreTerm(void) {
tcsetattr(STDOUT_FILENO, TCSADRAIN, &saveTerm);
}
static struct {
int read;
int write;
} winch;
static void sigwinch() {
struct winsize localWindow;
int error = ioctl(STDERR_FILENO, TIOCGWINSZ, &localWindow);
if (error) err(EX_IOERR, "ioctl(%d, TIOCGWINSZ, ...)", STDERR_FILENO);
ssize_t size = write(winch.write, &localWindow, sizeof(localWindow));
if (size < 0) err(EX_IOERR, "write(%d)", winch.write);
if ((size_t)size < sizeof(localWindow)) {
errx(EX_IOERR, "short write(%d)", winch.write);
}
}
static struct winsize remoteWindow;
static void readRemoteWindow(int remote) {
ssize_t size = read(remote, &remoteWindow, sizeof(remoteWindow));
if (size < 0) err(EX_IOERR, "read(%d)", remote);
if ((size_t)size < sizeof(remoteWindow)) errx(EX_IOERR, "short read(%d)", remote);
}
int main(int argc, char *argv[]) {
int error;
if (argc < 2) return EX_USAGE;
const char *path = argv[1];
int input = STDIN_FILENO;
int local = STDOUT_FILENO;
error = tcgetattr(local, &saveTerm);
if (error) err(EX_IOERR, "tcgetattr");
atexit(restoreTerm);
struct termios term = saveTerm;
term.c_lflag &= ~(ICANON | ECHO);
error = tcsetattr(local, TCSADRAIN, &term);
if (error) err(EX_IOERR, "tcsetattr");
error = pipe((int *)&winch);
if (error) err(EX_OSERR, "pipe");
signal(SIGWINCH, sigwinch);
sigwinch();
int remote = open(path, O_RDONLY);
if (remote < 0) err(EX_NOINPUT, "%s", path);
readRemoteWindow(remote);
int kq = kqueue();
if (kq < 0) err(EX_OSERR, "kqueue");
struct kevent events[3] = {
{ .ident = winch.read, .filter = EVFILT_READ, .flags = EV_ADD },
{ .ident = input, .filter = EVFILT_READ, .flags = EV_ADD },
{ .ident = remote, .filter = EVFILT_READ, .flags = EV_ADD },
};
int nevents = kevent(kq, events, 3, NULL, 0, NULL);
if (nevents < 0) err(EX_OSERR, "kevent");
char buf[4096];
bool truncated = false;
for (;;) {
struct kevent event;
int nevents = kevent(kq, NULL, 0, &event, 1, NULL);
if (nevents < 0) err(EX_OSERR, "kevent");
if (!nevents) continue;
if (event.ident == (uintptr_t)winch.read) {
for (;;) {
struct winsize localWindow;
ssize_t size = read(winch.read, &localWindow, sizeof(localWindow));
if (size < 0) err(EX_IOERR, "read(%d)", winch.read);
if ((size_t)size < sizeof(localWindow)) {
errx(EX_IOERR, "short read(%d)", winch.read);
}
if (
localWindow.ws_col == remoteWindow.ws_col
&& localWindow.ws_row == remoteWindow.ws_row
) break;
warnx(
"Please resize your terminal %hux%hu -> %hux%hu",
localWindow.ws_col, localWindow.ws_row,
remoteWindow.ws_col, remoteWindow.ws_row
);
}
}
if (event.ident == (uintptr_t)input) {
ssize_t size = read(input, buf, sizeof(buf));
if (size < 0) err(EX_IOERR, "read(%d)", input);
if (size == 1 && buf[0] == 'q') return EX_OK;
}
if (event.ident == (uintptr_t)remote) {
if (event.data < 0) {
off_t offset = lseek(remote, 0, SEEK_SET);
if (offset < 0) err(EX_IOERR, "lseek(%d)", remote);
truncated = true;
continue;
}
if (truncated) {
readRemoteWindow(remote);
sigwinch();
truncated = false;
continue;
}
ssize_t readSize = read(remote, buf, sizeof(buf));
if (readSize < 0) err(EX_IOERR, "read(%d)", remote);
ssize_t writeSize = write(local, buf, readSize);
if (writeSize < 0) err(EX_IOERR, "write(%d)", local);
if (writeSize < readSize) errx(EX_IOERR, "short write(%d)", local);
}
}
}
|