John Beppu | abb4772 | 2000-01-06 00:48:21 +0000 | [diff] [blame] | 1 | /* |
Erik Andersen | 0b874ed | 2000-01-06 01:14:56 +0000 | [diff] [blame^] | 2 | * Mini uniq implementation for busybox |
John Beppu | abb4772 | 2000-01-06 00:48:21 +0000 | [diff] [blame] | 3 | * |
| 4 | * |
| 5 | * Copyright (C) 1999 by Lineo, inc. |
| 6 | * Written by John Beppu <beppu@lineo.com> |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or modify |
| 9 | * it under the terms of the GNU General Public License as published by |
| 10 | * the Free Software Foundation; either version 2 of the License, or |
| 11 | * (at your option) any later version. |
| 12 | * |
| 13 | * This program is distributed in the hope that it will be useful, |
| 14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 16 | * General Public License for more details. |
| 17 | * |
| 18 | * You should have received a copy of the GNU General Public License |
| 19 | * along with this program; if not, write to the Free Software |
| 20 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 21 | * |
| 22 | */ |
| 23 | |
| 24 | #include "internal.h" |
| 25 | #include <stdio.h> |
| 26 | |
| 27 | static const char uniq_usage[] = |
| 28 | "haha\n" |
| 29 | ; |
| 30 | |
| 31 | /* max chars in line */ |
| 32 | #define UNIQ_MAX 4096 |
| 33 | |
| 34 | typedef void (Print)(FILE *, const char *); |
| 35 | |
| 36 | typedef int (Decide)(const char *, const char *); |
| 37 | |
| 38 | /* container for two lines to be compared */ |
| 39 | typedef struct { |
| 40 | char *a; |
| 41 | char *b; |
| 42 | int recurrence; |
| 43 | FILE *in; |
| 44 | FILE *out; |
| 45 | void *func; |
| 46 | } Subject; |
| 47 | |
| 48 | /* set up all the variables of a uniq operation */ |
| 49 | static Subject * |
| 50 | subject_init(Subject *self, FILE *in, FILE *out, void *func) |
| 51 | { |
| 52 | self->a = NULL; |
| 53 | self->b = NULL; |
| 54 | self->in = in; |
| 55 | self->out = out; |
| 56 | self->func = func; |
| 57 | self->recurrence = 0; |
| 58 | return self; |
| 59 | } |
| 60 | |
| 61 | /* point a and b to the appropriate lines; |
| 62 | * count the recurrences (if any) of a string; |
| 63 | */ |
| 64 | static Subject * |
| 65 | subject_next(Subject *self) |
| 66 | { |
| 67 | /* tmp line holders */ |
| 68 | static char line[2][UNIQ_MAX]; |
| 69 | static int alternator = 0; |
| 70 | |
| 71 | if (fgets(line[alternator], UNIQ_MAX, self->in)) { |
| 72 | self->a = self->b; |
| 73 | self->b = line[alternator]; |
| 74 | alternator ^= 1; |
| 75 | return self; |
| 76 | } |
| 77 | |
| 78 | return NULL; |
| 79 | } |
| 80 | |
| 81 | static Subject * |
| 82 | subject_last(Subject *self) |
| 83 | { |
| 84 | self->a = self->b; |
| 85 | self->b = NULL; |
| 86 | return self; |
| 87 | } |
| 88 | |
| 89 | static Subject * |
| 90 | subject_study(Subject *self) |
| 91 | { |
| 92 | if (self->a == NULL) { |
| 93 | return self; |
| 94 | } |
| 95 | if (self->b == NULL) { |
| 96 | fprintf(self->out, "%s", self->a); |
| 97 | return self; |
| 98 | } |
| 99 | if (strcmp(self->a, self->b) == 0) { |
| 100 | self->recurrence++; |
| 101 | } else { |
| 102 | fprintf(self->out, "%s", self->a); |
| 103 | self->recurrence = 0; |
| 104 | } |
| 105 | return self; |
| 106 | } |
| 107 | |
| 108 | /* one variable is the decision algo */ |
| 109 | /* another variable is the printing algo */ |
| 110 | |
| 111 | /* I don't think I have to have more than a 1 line memory |
| 112 | this is the one constant */ |
| 113 | |
| 114 | /* it seems like GNU/uniq only takes one or two files as an option */ |
| 115 | |
| 116 | /* ________________________________________________________________________ */ |
| 117 | int |
| 118 | uniq_main(int argc, char **argv) |
| 119 | { |
| 120 | int i; |
| 121 | char opt; |
| 122 | FILE *in, *out; |
| 123 | Subject s; |
| 124 | |
| 125 | /* init */ |
| 126 | in = stdin; |
| 127 | out = stdout; |
| 128 | |
| 129 | subject_init(&s, in, out, NULL); |
| 130 | while (subject_next(&s)) { |
| 131 | subject_study(&s); |
| 132 | } |
| 133 | subject_last(&s); |
| 134 | subject_study(&s); |
| 135 | exit(0); |
| 136 | |
| 137 | /* XXX : finish the tedious stuff */ |
| 138 | |
| 139 | /* parse argv[] */ |
| 140 | for (i = 1; i < argc; i++) { |
| 141 | if (argv[i][0] == '-') { |
| 142 | opt = argv[i][1]; |
| 143 | switch (opt) { |
Erik Andersen | 0b874ed | 2000-01-06 01:14:56 +0000 | [diff] [blame^] | 144 | case '-': |
John Beppu | abb4772 | 2000-01-06 00:48:21 +0000 | [diff] [blame] | 145 | case 'h': |
| 146 | usage(uniq_usage); |
| 147 | default: |
| 148 | usage(uniq_usage); |
| 149 | } |
| 150 | } else { |
| 151 | break; |
| 152 | } |
| 153 | } |
| 154 | |
| 155 | exit(0); |
| 156 | } |
| 157 | |
Erik Andersen | 0b874ed | 2000-01-06 01:14:56 +0000 | [diff] [blame^] | 158 | /* $Id: uniq.c,v 1.2 2000/01/06 01:14:56 erik Exp $ */ |