Subversion Repositories planix.SVN

Rev

Rev 2 | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
2 - 1 
#include <u.h>
2 
#include <libc.h>
3 
#include <bio.h>
4 
 
5 
#define LB 2048
6 
int	one;
7 
int	two;
8 
int	three;
9 
 
10 
char	*ldr[3];
11 
 
12 
Biobuf *ib1;
13 
Biobuf *ib2;
14 
Biobuf *openfil(char*);
15 
int	rd(Biobuf*, char*);
16 
void	wr(char*, int);
17 
void	copy(Biobuf*, char*, int);
18 
int	compare(char*, char*);
19 
 
20 
void
21 
main(int argc, char *argv[])
22 
{
23 
	int l;
24 
	char	lb1[LB],lb2[LB];
25 
 
26 
	ldr[0] = "";
27 
	ldr[1] = "\t";
28 
	ldr[2] = "\t\t";
29 
	l = 1;
30 
	ARGBEGIN{
31 
	case '1':
32 
		if(!one) {
33 
			one = 1;
34 
			ldr[1][0] =
35 
			ldr[2][l--] = '\0';
36 
		}
37 
		break;
38 
 
39 
	case '2':
40 
		if(!two) {
41 
			two = 1;
42 
			ldr[2][l--] = '\0';
43 
		}
44 
		break;
45 
 
46 
	case '3':
47 
		three = 1;
48 
		break;
49 
 
50 
	default:
51 
		goto Usage;
52 
 
53 
	}ARGEND
54 
 
55 
	if(argc < 2) {
56 
    Usage:
57 
		fprint(2, "usage: comm [-123] file1 file2\n");
58 
		exits("usage");
59 
	}
60 
 
61 
	ib1 = openfil(argv[0]);
62 
	ib2 = openfil(argv[1]);
63 
 
64 
 
65 
	if(rd(ib1,lb1) < 0){
66 
		if(rd(ib2,lb2) < 0)
67 
			exits(0);
68 
		copy(ib2,lb2,2);
69 
	}
70 
	if(rd(ib2,lb2) < 0)
71 
		copy(ib1,lb1,1);
72 
 
73 
	for(;;){
74 
		switch(compare(lb1,lb2)) {
75 
		case 0:
76 
			wr(lb1,3);
77 
			if(rd(ib1,lb1) < 0) {
78 
				if(rd(ib2,lb2) < 0)
79 
					exits(0);
80 
				copy(ib2,lb2,2);
81 
			}
82 
			if(rd(ib2,lb2) < 0)
83 
				copy(ib1,lb1,1);
84 
			continue;
85 
 
86 
		case 1:
87 
			wr(lb1,1);
88 
			if(rd(ib1,lb1) < 0)
89 
				copy(ib2,lb2,2);
90 
			continue;
91 
 
92 
		case 2:
93 
			wr(lb2,2);
94 
			if(rd(ib2,lb2) < 0)
95 
				copy(ib1,lb1,1);
96 
			continue;
97 
		}
98 
	}
99 
}
100 
 
101 
int
102 
rd(Biobuf *file, char *buf)
103 
{
104 
	int i, c;
105 
 
106 
	i = 0;
107 
	while((c = Bgetc(file)) != Beof) {
108 
		*buf = c;
109 
		if(c == '\n' || i > LB-2) {
110 
			*buf = '\0';
111 
			return 0;
112 
		}
113 
		i++;
114 
		buf++;
115 
	}
116 
	return -1;
117 
}
118 
 
119 
void
120 
wr(char *str, int n)
121 
{
122 
 
123 
	switch(n){
124 
		case 1:
125 
			if(one)
126 
				return;
127 
			break;
128 
 
129 
		case 2:
130 
			if(two)
131 
				return;
132 
			break;
133 
 
134 
		case 3:
135 
			if(three)
136 
				return;
137 
	}
138 
	print("%s%s\n", ldr[n-1],str);
139 
}
140 
 
141 
void
142 
copy(Biobuf *ibuf, char *lbuf, int n)
143 
{
144 
	do
145 
		wr(lbuf,n);
146 
	while(rd(ibuf,lbuf) >= 0);
147 
	exits(0);
148 
}
149 
 
150 
int
151 
compare(char *a, char *b)
152 
{
153 
	while(*a == *b){
154 
		if(*a == '\0')
155 
			return 0;
156 
		a++;
157 
		b++;
158 
	}
159 
	if(*a < *b)
160 
		return 1;
161 
	return 2;
162 
}
163 
 
164 
Biobuf*
165 
openfil(char *s)
166 
{
167 
	Biobuf *b;
168 
 
169 
	if(s[0]=='-' && s[1]==0)
170 
		s = "/fd/0";
171 
	b = Bopen(s, OREAD);
172 
	if(b)
173 
		return b;
174 
	fprint(2,"comm: cannot open %s: %r\n",s);
175 
	exits("open");
176 
	return 0;	/* shut up ken */
177 
}