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
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
|
/* vi: set sw=4 ts=4: */
/*
* Mini uniq implementation for busybox
*
*
* Copyright (C) 1999,2000 by Lineo, inc.
* Written by John Beppu <beppu@lineo.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include "internal.h"
#include <stdio.h>
#include <string.h>
#include <errno.h>
static const char uniq_usage[] =
"uniq [OPTION]... [INPUT [OUTPUT]]\n"
#ifndef BB_FEATURE_TRIVIAL_HELP
"\nDiscard all but one of successive identical lines from INPUT\n"
"(or standard input), writing to OUTPUT (or standard output).\n"
#endif
;
/* max chars in line */
#define UNIQ_MAX 4096
typedef void (Print) (FILE *, const char *);
typedef int (Decide) (const char *, const char *);
/* container for two lines to be compared */
typedef struct {
char *a;
char *b;
int recurrence;
FILE *in;
FILE *out;
void *func;
} Subject;
/* set up all the variables of a uniq operation */
static Subject *subject_init(Subject * self, FILE * in, FILE * out,
void *func)
{
self->a = NULL;
self->b = NULL;
self->in = in;
self->out = out;
self->func = func;
self->recurrence = 0;
return self;
}
/* point a and b to the appropriate lines;
* count the recurrences (if any) of a string;
*/
static Subject *subject_next(Subject * self)
{
/* tmp line holders */
static char line[2][UNIQ_MAX];
static int alternator = 0;
if (fgets(line[alternator], UNIQ_MAX, self->in)) {
self->a = self->b;
self->b = line[alternator];
alternator ^= 1;
return self;
}
return NULL;
}
static Subject *subject_last(Subject * self)
{
self->a = self->b;
self->b = NULL;
return self;
}
static Subject *subject_study(Subject * self)
{
if (self->a == NULL) {
return self;
}
if (self->b == NULL) {
fprintf(self->out, "%s", self->a);
return self;
}
if (strcmp(self->a, self->b) == 0) {
self->recurrence++;
} else {
fprintf(self->out, "%s", self->a);
self->recurrence = 0;
}
return self;
}
static int
set_file_pointers(int schema, FILE ** in, FILE ** out, char **argv)
{
switch (schema) {
case 0:
*in = stdin;
*out = stdout;
break;
case 1:
*in = fopen(argv[0], "r");
*out = stdout;
break;
case 2:
*in = fopen(argv[0], "r");
*out = fopen(argv[1], "w");
break;
}
if (*in == NULL) {
errorMsg("%s: %s\n", argv[0], strerror(errno));
return errno;
}
if (*out == NULL) {
errorMsg("%s: %s\n", argv[1], strerror(errno));
return errno;
}
return 0;
}
/* one variable is the decision algo */
/* another variable is the printing algo */
/* I don't think I have to have more than a 1 line memory
this is the one constant */
/* it seems like GNU/uniq only takes one or two files as an option */
/* ________________________________________________________________________ */
int uniq_main(int argc, char **argv)
{
int i;
char opt;
FILE *in, *out;
Subject s;
/* parse argv[] */
for (i = 1; i < argc; i++) {
if (argv[i][0] == '-') {
opt = argv[i][1];
switch (opt) {
case '-':
case 'h':
usage(uniq_usage);
default:
usage(uniq_usage);
}
} else {
break;
}
}
/* 0 src: stdin; dst: stdout */
/* 1 src: file; dst: stdout */
/* 2 src: file; dst: file */
if (set_file_pointers((argc - 1), &in, &out, &argv[i])) {
exit(1);
}
subject_init(&s, in, out, NULL);
while (subject_next(&s)) {
subject_study(&s);
}
subject_last(&s);
subject_study(&s);
return(0);
}
/* $Id: uniq.c,v 1.12 2000/07/14 01:51:25 kraai Exp $ */
|
