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
|
#include <u.h>
#include <libc.h>
#include <ctype.h>
#define BUF 65536
int sflag = 0;
int lflag = 0;
int Lflag = 0;
static void usage(void);
char **
seekoff(int fd, char *name, char **argv)
{
vlong o;
if(*argv){
if (!isascii(**argv) || !isdigit(**argv))
usage();
o = strtoll(*argv++, 0, 0);
if(seek(fd, o, 0) < 0){
if(!sflag) fprint(2, "cmp: %s: seek by %lld: %r\n",
name, o);
exits("seek");
}
}
return argv;
}
void
main(int argc, char *argv[])
{
int n, i;
uchar *p, *q;
uchar buf1[BUF], buf2[BUF];
int f1, f2;
vlong nc = 1, l = 1;
char *name1, *name2;
uchar *b1s, *b1e, *b2s, *b2e;
ARGBEGIN{
case 's': sflag = 1; break;
case 'l': lflag = 1; break;
case 'L': Lflag = 1; break;
default: usage();
}ARGEND
if(argc < 2 || argc > 4)
usage();
if((f1 = open(name1 = *argv++, OREAD)) == -1){
if(!sflag) perror(name1);
exits("open");
}
if((f2 = open(name2 = *argv++, OREAD)) == -1){
if(!sflag) perror(name2);
exits("open");
}
argv = seekoff(f1, name1, argv);
argv = seekoff(f2, name2, argv);
if(*argv)
usage();
b1s = b1e = buf1;
b2s = b2e = buf2;
for(;;){
if(b1s >= b1e){
if(b1s >= &buf1[BUF])
b1s = buf1;
n = read(f1, b1s, &buf1[BUF] - b1s);
b1e = b1s + n;
}
if(b2s >= b2e){
if(b2s >= &buf2[BUF])
b2s = buf2;
n = read(f2, b2s, &buf2[BUF] - b2s);
b2e = b2s + n;
}
n = b2e - b2s;
if(n > b1e - b1s)
n = b1e - b1s;
if(n <= 0)
break;
if(memcmp((void *)b1s, (void *)b2s, n) != 0){
if(sflag)
exits("differ");
for(p = b1s, q = b2s, i = 0; i < n; p++, q++, i++) {
if(*p == '\n')
l++;
if(*p != *q){
if(!lflag){
print("%s %s differ: char %lld",
name1, name2, nc+i);
print(Lflag?" line %lld\n":"\n", l);
exits("differ");
}
print("%6lld 0x%.2x 0x%.2x\n", nc+i, *p, *q);
}
}
}
if(Lflag)
for(p = b1s; p < b1e;)
if(*p++ == '\n')
l++;
nc += n;
b1s += n;
b2s += n;
}
if (b1e - b1s < 0 || b2e - b2s < 0) {
if (!sflag) {
if (b1e - b1s < 0)
print("error on %s after %lld bytes\n",
name1, nc-1);
if (b2e - b2s < 0)
print("error on %s after %lld bytes\n",
name2, nc-1);
}
exits("read error");
}
if(b1e - b1s == b2e - b2s)
exits((char *)0);
if(!sflag)
print("EOF on %s after %lld bytes\n",
(b1e - b1s > b2e - b2s)? name2 : name1, nc-1);
exits("EOF");
}
static void
usage(void)
{
print("usage: cmp [-lLs] file1 file2 [offset1 [offset2] ]\n");
exits("usage");
}
|
