diff options
Diffstat (limited to 'games/random/randomize_fd.c')
| -rw-r--r-- | games/random/randomize_fd.c | 219 |
1 files changed, 219 insertions, 0 deletions
diff --git a/games/random/randomize_fd.c b/games/random/randomize_fd.c new file mode 100644 index 0000000..447663cf --- /dev/null +++ b/games/random/randomize_fd.c @@ -0,0 +1,219 @@ +/* + * Copyright (C) 2003 Sean Chittenden <seanc@FreeBSD.org> + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * $FreeBSD$ + */ + +#include "randomize_fd.h" + +struct rand_node *rand_root; +struct rand_node *rand_tail; + + +static +struct rand_node *rand_node_allocate(void) +{ + struct rand_node *n; + + n = (struct rand_node *)malloc(sizeof(struct rand_node)); + if (n == NULL) + err(1, "malloc"); + + n->len = 0; + n->cp = NULL; + n->next = NULL; + return(n); +} + + +static +void rand_node_free(struct rand_node *n) +{ + if (n != NULL) { + if (n->cp != NULL) + free(n->cp); + + free(n); + } +} + + +static +void rand_node_free_rec(struct rand_node *n) +{ + if (n != NULL) { + if (n->next != NULL) + rand_node_free_rec(n->next); + + rand_node_free(n); + } +} + + +static +struct rand_node *rand_node_append(struct rand_node *n) +{ + if (rand_root == NULL) { + rand_root = rand_tail = n; + return(n); + } else { + rand_tail->next = n; + rand_tail = n; + + return(n); + } +} + + +int randomize_fd(int fd, int type, int unique, double denom) +{ + u_char *buf, *p; + u_int numnode, j, selected, slen; + struct rand_node *n, *prev; + int bufc, bufleft, buflen, eof, fndstr, i, len, ret; + + rand_root = rand_tail = NULL; + bufc = bufleft = eof = fndstr = numnode = 0; + + if (type == RANDOM_TYPE_UNSET) + type = RANDOM_TYPE_LINES; + + buflen = sizeof(u_char) * MAXBSIZE; + buf = (u_char *)malloc(buflen); + if (buf == NULL) + err(1, "malloc"); + + while (!eof) { + /* Check to see if we have bits in the buffer */ + if (bufleft == 0) { + len = read(fd, buf, buflen); + if (len == -1) + err(1, "read"); + else if (len == 0) + break; + else if (len < buflen) { + buflen = len; + eof++; + } + + bufleft = len; + } + + /* Look for a newline */ + for (i = bufc; i <= buflen; i++, bufleft--) { + if (i == buflen) { + if (fndstr) { + if (!eof) { + memmove(buf, &buf[bufc], i - bufc); + i = i - bufc; + bufc = 0; + len = read(fd, &buf[i], buflen - i); + if (len == -1) + err(1, "read"); + else if (len == 0) { + eof++; + break; + } else if (len < buflen -i ) + buflen = i + len; + + bufleft = len; + fndstr = 0; + } + } else { + p = (u_char *)realloc(buf, buflen * 2); + if (p == NULL) + err(1, "realloc"); + + buf = p; + if (!eof) { + len = read(fd, &buf[i], buflen); + if (len == -1) + err(1, "read"); + else if (len == 0) { + eof++; + break; + } else if (len < buflen -i ) + buflen = len; + + bufleft = len; + } + + buflen *= 2; + } + } + + if ((type == RANDOM_TYPE_LINES && buf[i] == '\n') || + (type == RANDOM_TYPE_WORDS && isspace((int)buf[i])) || + (eof && i == buflen - 1)) { + n = rand_node_allocate(); + slen = i - bufc; + n->len = slen + 2; + n->cp = (u_char *)malloc(slen + 2); + if (n->cp == NULL) + err(1, "malloc"); + + memmove(n->cp, &buf[bufc], slen); + n->cp[slen] = buf[i]; + n->cp[slen + 1] = '\0'; + bufc = i + 1; + fndstr = 1; + rand_node_append(n); + numnode++; + } + } + } + + (void)close(fd); + + for (i = numnode; i > 0; i--) { + selected = ((int)denom * random())/(((double)RAND_MAX + 1) / numnode); + + for (j = 0, prev = n = rand_root; n != NULL; j++, prev = n, n = n->next) { + if (j == selected) { + ret = printf("%.*s", n->len - 1, n->cp); + if (ret < 0) + err(1, "printf"); + if (unique) { + if (n == rand_root) + rand_root = n->next; + if (n == rand_tail) + rand_tail = prev; + + prev->next = n->next; + rand_node_free(n); + numnode--; + break; + } + } + } + } + + fflush(stdout); + + if (!unique) + rand_node_free_rec(rand_root); + + return(0); +} |
