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
|
/* vi: set sw=4 ts=4: */
/*
* Mini cmp implementation for busybox
*
* Copyright (C) 2000,2001 by Matt Kraai <kraai@alumni.carnegiemellon.edu>
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
/* BB_AUDIT SUSv3 (virtually) compliant -- uses nicer GNU format for -l. */
/* http://www.opengroup.org/onlinepubs/007904975/utilities/cmp.html */
/* Mar 16, 2003 Manuel Novoa III (mjn3@codepoet.org)
*
* Original version majorly reworked for SUSv3 compliance, bug fixes, and
* size optimizations. Changes include:
* 1) Now correctly distinguishes between errors and actual file differences.
* 2) Proper handling of '-' args.
* 3) Actual error checking of i/o.
* 4) Accept SUSv3 -l option. Note that we use the slightly nicer gnu format
* in the '-l' case.
*/
#include "libbb.h"
static const char fmt_eof[] ALIGN1 = "cmp: EOF on %s\n";
static const char fmt_differ[] ALIGN1 = "%s %s differ: char %"OFF_FMT"u, line %u\n";
// This fmt_l_opt uses gnu-isms. SUSv3 would be "%.0s%.0s%"OFF_FMT"u %o %o\n"
static const char fmt_l_opt[] ALIGN1 = "%.0s%.0s%"OFF_FMT"u %3o %3o\n";
static const char opt_chars[] ALIGN1 = "sl";
#define CMP_OPT_s (1<<0)
#define CMP_OPT_l (1<<1)
int cmp_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int cmp_main(int argc UNUSED_PARAM, char **argv)
{
FILE *fp1, *fp2, *outfile = stdout;
const char *filename1, *filename2 = "-";
IF_DESKTOP(off_t skip1 = 0, skip2 = 0;)
off_t char_pos = 0;
int line_pos = 1; /* Hopefully won't overflow... */
const char *fmt;
int c1, c2;
unsigned opt;
int retval = 0;
xfunc_error_retval = 2; /* 1 is returned if files are different. */
opt_complementary = "-1"
IF_DESKTOP(":?4")
IF_NOT_DESKTOP(":?2")
":l--s:s--l";
opt = getopt32(argv, opt_chars);
argv += optind;
filename1 = *argv;
fp1 = xfopen_stdin(filename1);
if (*++argv) {
filename2 = *argv;
#if ENABLE_DESKTOP
if (*++argv) {
skip1 = XATOOFF(*argv);
if (*++argv) {
skip2 = XATOOFF(*argv);
}
}
#endif
}
fp2 = xfopen_stdin(filename2);
if (fp1 == fp2) { /* Paranoia check... stdin == stdin? */
/* Note that we don't bother reading stdin. Neither does gnu wc.
* But perhaps we should, so that other apps down the chain don't
* get the input. Consider 'echo hello | (cmp - - && cat -)'.
*/
return 0;
}
if (opt & CMP_OPT_l)
fmt = fmt_l_opt;
else
fmt = fmt_differ;
#if ENABLE_DESKTOP
while (skip1) { getc(fp1); skip1--; }
while (skip2) { getc(fp2); skip2--; }
#endif
do {
c1 = getc(fp1);
c2 = getc(fp2);
++char_pos;
if (c1 != c2) { /* Remember: a read error may have occurred. */
retval = 1; /* But assume the files are different for now. */
if (c2 == EOF) {
/* We know that fp1 isn't at EOF or in an error state. But to
* save space below, things are setup to expect an EOF in fp1
* if an EOF occurred. So, swap things around.
*/
fp1 = fp2;
filename1 = filename2;
c1 = c2;
}
if (c1 == EOF) {
die_if_ferror(fp1, filename1);
fmt = fmt_eof; /* Well, no error, so it must really be EOF. */
outfile = stderr;
/* There may have been output to stdout (option -l), so
* make sure we fflush before writing to stderr. */
fflush_all();
}
if (!(opt & CMP_OPT_s)) {
if (opt & CMP_OPT_l) {
line_pos = c1; /* line_pos is unused in the -l case. */
}
fprintf(outfile, fmt, filename1, filename2, char_pos, line_pos, c2);
if (opt) { /* This must be -l since not -s. */
/* If we encountered an EOF,
* the while check will catch it. */
continue;
}
}
break;
}
if (c1 == '\n') {
++line_pos;
}
} while (c1 != EOF);
die_if_ferror(fp1, filename1);
die_if_ferror(fp2, filename2);
fflush_stdout_and_exit(retval);
}
|
