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
|
/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <AK/Vector.h>
#include <LibCore/CArgsParser.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdio.h>
#include <unistd.h>
static Vector<int> collect_fds(Vector<const char*> paths, bool append, bool* err)
{
int oflag;
mode_t mode;
if (append) {
oflag = O_APPEND;
mode = 0;
} else {
oflag = O_CREAT | O_WRONLY | O_TRUNC;
mode = S_IROTH | S_IWOTH | S_IRGRP | S_IWGRP | S_IRUSR | S_IWUSR;
}
Vector<int> fds;
for (const char* path : paths) {
int fd = open(path, oflag, mode);
if (fd < 0) {
perror("failed to open file for writing");
*err = true;
} else {
fds.append(fd);
}
}
fds.append(STDOUT_FILENO);
return fds;
}
static void copy_stdin(Vector<int>& fds, bool* err)
{
for (;;) {
char buf[4096];
ssize_t nread = read(STDIN_FILENO, buf, sizeof(buf));
if (nread == 0)
break;
if (nread < 0) {
perror("read() error");
*err = true;
// a failure to read from stdin should lead to an early exit
return;
}
Vector<int> broken_fds;
for (int i = 0; i < fds.size(); ++i) {
auto fd = fds.at(i);
int twrite = 0;
while (twrite != nread) {
ssize_t nwrite = write(fd, buf + twrite, nread - twrite);
if (nwrite < 0) {
if (errno == EINTR) {
continue;
} else {
perror("write() failed");
*err = true;
broken_fds.append(fd);
// write failures to a successfully opened fd shall
// prevent further writes, but shall not block writes
// to the other open fds
break;
}
} else {
twrite += nwrite;
}
}
}
// remove any fds which we can no longer write to for subsequent copies
for (auto to_remove : broken_fds)
fds.remove_first_matching([&](int fd) { return to_remove == fd; });
}
}
static void close_fds(Vector<int>& fds)
{
for (int fd : fds) {
int closed = close(fd);
if (closed < 0) {
perror("failed to close output file");
}
}
}
static void int_handler(int)
{
// pass
}
int main(int argc, char** argv)
{
bool append = false;
bool ignore_interrupts = false;
Vector<const char*> paths;
Core::ArgsParser args_parser;
args_parser.add_option(append, "Append, don't overwrite", "append", 'a');
args_parser.add_option(ignore_interrupts, "Ignore SIGINT", "ignore-interrupts", 'i');
args_parser.add_positional_argument(paths, "Files to copy stdin to", "file", Core::ArgsParser::Required::No);
args_parser.parse(argc, argv);
if (ignore_interrupts) {
if (signal(SIGINT, int_handler) == SIG_ERR)
perror("failed to install SIGINT handler");
}
bool err_open = false;
bool err_write = false;
auto fds = collect_fds(paths, append, &err_open);
copy_stdin(fds, &err_write);
close_fds(fds);
return (err_open || err_write) ? 1 : 0;
}
|
