blob: 7c475ca07ce6fa6364a42981047e9278432af9c6 (
plain)
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
|
/* vi: set sw=4 ts=4:
*
* echo.c - echo supporting -n and -e.
*
* Copyright 2007 Rob Landley <rob@landley.net>
*
* See http://www.opengroup.org/onlinepubs/009695399/utilities/echo.html
config ECHO
bool "echo"
default y
help
usage: echo [-ne] [args...]
Write each argument to stdout, with one space between each, followed
by a newline.
-n No trailing newline.
-e Process the following escape sequences:
\\ backslash
\a alert (beep/flash)
\b backspace
\c Stop output here (avoids trailing newline)
\f form feed
\n newline
\r carriage return
\t horizontal tab
\v vertical tab
*/
#include "toys.h"
void echo_main(void)
{
int i = 0;
char *arg, *from = "\\abfnrtv", *to = "\\\a\b\f\n\r\t\v";
for (;;) {
arg = toys.optargs[i];
if (!arg) break;
if (i++) xputc(' ');
// Handle -e
if (toys.optflags&2) {
int c, j = 0;
for (;;) {
c = arg[j++];
if (!c) break;
if (c == '\\') {
char *found;
int d = arg[j++];
// handle \escapes
if (d) {
found = strchr(from, d);
if (found) c = to[found-from];
else if (d == 'c') goto done;
else if (d == '0') {
c = 0;
while (arg[j]>='0' && arg[j]<='7')
c = (c*8)+arg[j++]-'0';
}
}
}
xputc(c);
}
} else xprintf("%s", arg);
}
// Output "\n" if no -n
if (!(toys.optflags&1)) xputc('\n');
done:
xflush();
}
|
