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
|
/* fold.c - fold text
*
* Copyright 2014 Samuel Holland <samuel@sholland.net>
*
* See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/fold.html
USE_FOLD(NEWTOY(fold, "bsuw#<1", TOYFLAG_USR|TOYFLAG_BIN))
config FOLD
bool "fold"
default n
help
usage: fold [-bsu] [-w WIDTH] [FILE...]
Folds (wraps) or unfolds ascii text by adding or removing newlines.
Default line width is 80 columns for folding and infinite for unfolding.
-b Fold based on bytes instead of columns
-s Fold/unfold at whitespace boundaries if possible
-u Unfold text (and refold if -w is given)
-w Set lines to WIDTH columns or bytes
*/
#define FOR_fold
#include "toys.h"
GLOBALS(
int width;
)
// wcwidth mbrtowc
void do_fold(int fd, char *name)
{
int bufsz, len = 0, maxlen;
if (toys.optflags & FLAG_w) maxlen = TT.width;
else if (toys.optflags & FLAG_u) maxlen = 0;
else maxlen = 80;
while ((bufsz = read(fd, toybuf, sizeof(toybuf))) > 0) {
char *buf = toybuf;
int pos = 0, split = -1;
while (pos < bufsz) {
switch (buf[pos]) {
case '\n':
// print everything but the \n, then move on to the next buffer
if ((toys.optflags & FLAG_u) && buf[pos-1] != '\n'
&& buf[pos+1] != '\n') {
xwrite(1, buf, pos);
bufsz -= pos + 1;
buf += pos + 1;
pos = 0;
split = -1;
// reset len, FLAG_b or not; just print multiple lines at once
} else len = 0;
break;
case '\b':
// len cannot be negative; not allowed to wrap after backspace
if (toys.optflags & FLAG_b) len++;
else if (len > 0) len--;
break;
case '\r':
// not allowed to wrap after carriage return
if (toys.optflags & FLAG_b) len++;
else len = 0;
break;
case '\t':
// round to 8, but we add one after falling through
// (because of whitespace, but it also takes care of FLAG_b)
if (!(toys.optflags & FLAG_b)) len = (len & ~7) + 7;
case ' ':
split = pos;
default:
len++;
}
// we don't want to double up \n; not allowed to wrap before \b
if (maxlen > 0 && len >= maxlen && buf[pos+1] != '\n' && buf[pos+1] != '\b') {
if (!(toys.optflags & FLAG_s) || split < 0) split = pos;
xwrite(1, buf, split + 1);
xputc('\n');
bufsz -= split + 1;
buf += split + 1;
len = pos = 0;
split = -1;
} else pos++;
}
xwrite(1, buf, bufsz);
}
xputc('\n');
}
void fold_main(void)
{
loopfiles(toys.optargs, do_fold);
}
|
