Make this compile with gcc40: rename variables so that they don't collide
[dragonfly.git] / games / random / randomize_fd.c
1 /*
2  * Copyright (C) 2003 Sean Chittenden <seanc@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD: src/games/random/randomize_fd.c,v 1.2.2.1 2003/02/15 10:34:35 seanc Exp $
27  * $DragonFly: src/games/random/randomize_fd.c,v 1.2 2003/06/17 04:25:24 dillon Exp $
28  */
29
30 #include <sys/types.h>
31 #include <sys/param.h>
32
33 #include <ctype.h>
34 #include <err.h>
35 #include <stdlib.h>
36 #include <stdio.h>
37 #include <string.h>
38 #include <unistd.h>
39
40 #include "randomize_fd.h"
41
42 static struct rand_node *rand_root;
43 static struct rand_node *rand_tail;
44
45 static struct rand_node *
46 rand_node_allocate(void)
47 {
48         struct rand_node *n;
49
50         n = (struct rand_node *)malloc(sizeof(struct rand_node));
51         if (n == NULL)
52                 err(1, "malloc");
53
54         n->len = 0;
55         n->cp = NULL;
56         n->next = NULL;
57         return(n);
58 }
59
60 static void
61 rand_node_free(struct rand_node *n)
62 {
63         if (n != NULL) {
64                 if (n->cp != NULL)
65                         free(n->cp);
66
67                 free(n);
68         }
69 }
70
71 static void
72 rand_node_free_rec(struct rand_node *n)
73 {
74         if (n != NULL) {
75                 if (n->next != NULL)
76                         rand_node_free_rec(n->next);
77
78                 rand_node_free(n);
79         }
80 }
81
82 static void
83 rand_node_append(struct rand_node *n)
84 {
85         if (rand_root == NULL)
86                 rand_root = rand_tail = n;
87         else {
88                 rand_tail->next = n;
89                 rand_tail = n;
90         }
91 }
92
93 int
94 randomize_fd(int fd, int type, int unique, double denom)
95 {
96         u_char *buf, *p;
97         u_int numnode, j, selected, slen;
98         struct rand_node *n, *prev;
99         int bufleft, eof, fndstr, ret;
100         size_t bufc, buflen, i;
101         ssize_t len;
102
103         rand_root = rand_tail = NULL;
104         bufc = i = 0;
105         bufleft = eof = fndstr = numnode = ret = 0;
106
107         if (type == RANDOM_TYPE_UNSET)
108                 type = RANDOM_TYPE_LINES;
109
110         buflen = sizeof(u_char) * MAXBSIZE;
111         buf = (u_char *)malloc(buflen);
112         if (buf == NULL)
113                 err(1, "malloc");
114
115         while (!eof) {
116                 /* Check to see if we have bits in the buffer */
117                 if (bufleft == 0) {
118                         len = read(fd, buf, buflen);
119                         if (len == -1)
120                                 err(1, "read");
121                         else if (len == 0) {
122                                 eof++;
123                                 break;
124                         } else if ((size_t)len < buflen)
125                                 buflen = (size_t)len;
126
127                         bufleft = (int)len;
128                 }
129
130                 /* Look for a newline */
131                 for (i = bufc; i <= buflen && bufleft >= 0; i++, bufleft--) {
132                         if (i == buflen) {
133                                 if (fndstr) {
134                                         if (!eof) {
135                                                 memmove(buf, &buf[bufc], i - bufc);
136                                                 i -= bufc;
137                                                 bufc = 0;
138                                                 len = read(fd, &buf[i], buflen - i);
139                                                 if (len == -1)
140                                                         err(1, "read");
141                                                 else if (len == 0) {
142                                                         eof++;
143                                                         break;
144                                                 } else if (len < (ssize_t)(buflen - i))
145                                                         buflen = i + (size_t)len;
146
147                                                 bufleft = (int)len;
148                                                 fndstr = 0;
149                                         }
150                                 } else {
151                                         p = (u_char *)realloc(buf, buflen * 2);
152                                         if (p == NULL)
153                                                 err(1, "realloc");
154
155                                         buf = p;
156                                         if (!eof) {
157                                                 len = read(fd, &buf[i], buflen);
158                                                 if (len == -1)
159                                                         err(1, "read");
160                                                 else if (len == 0) {
161                                                         eof++;
162                                                         break;
163                                                 } else if (len < (ssize_t)(buflen - i))
164                                                         buflen = (size_t)len;
165
166                                                 bufleft = (int)len;
167                                         }
168
169                                         buflen *= 2;
170                                 }
171                         }
172
173                         if ((type == RANDOM_TYPE_LINES && buf[i] == '\n') ||
174                             (type == RANDOM_TYPE_WORDS && isspace((int)buf[i])) ||
175                             (eof && i == buflen - 1)) {
176                         make_token:
177                                 n = rand_node_allocate();
178                                 if (-1 != (int)i) {
179                                         slen = i - (u_long)bufc;
180                                         n->len = slen + 2;
181                                         n->cp = (u_char *)malloc(slen + 2);
182                                         if (n->cp == NULL)
183                                                 err(1, "malloc");
184
185                                         memmove(n->cp, &buf[bufc], slen);
186                                         n->cp[slen] = buf[i];
187                                         n->cp[slen + 1] = '\0';
188                                         bufc = i + 1;
189                                 }
190                                 rand_node_append(n);
191                                 fndstr = 1;
192                                 numnode++;
193                         }
194                 }
195         }
196
197         (void)close(fd);
198
199         /* Necessary evil to compensate for files that don't end with a newline */
200         if (bufc != i) {
201                 i--;
202                 goto make_token;
203         }
204
205         for (i = numnode; i > 0; i--) {
206                 selected = ((int)denom * random())/(((double)RAND_MAX + 1) / numnode);
207
208                 for (j = 0, prev = n = rand_root; n != NULL; j++, prev = n, n = n->next) {
209                         if (j == selected) {
210                                 if (n->cp == NULL)
211                                         break;
212
213                                 ret = printf("%.*s", (int)n->len - 1, n->cp);
214                                 if (ret < 0)
215                                         err(1, "printf");
216                                 if (unique) {
217                                         if (n == rand_root)
218                                                 rand_root = n->next;
219                                         if (n == rand_tail)
220                                                 rand_tail = prev;
221
222                                         prev->next = n->next;
223                                         rand_node_free(n);
224                                         numnode--;
225                                         break;
226                                 }
227                         }
228                 }
229         }
230
231         fflush(stdout);
232
233         if (!unique)
234                 rand_node_free_rec(rand_root);
235
236         return(0);
237 }