ft_stopwords.c
上传用户:romrleung
上传日期:2022-05-23
资源大小:18897k
文件大小:3k
- /* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB
- 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 */
- /* Written by Sergei A. Golubchik, who has a shared copyright to this code */
- #include "ftdefs.h"
- #include "my_handler.h"
- typedef struct st_ft_stopwords
- {
- const char * pos;
- uint len;
- } FT_STOPWORD;
- static TREE *stopwords3=NULL;
- static int FT_STOPWORD_cmp(void* cmp_arg __attribute__((unused)),
- FT_STOPWORD *w1, FT_STOPWORD *w2)
- {
- return mi_compare_text(default_charset_info,
- (uchar *)w1->pos,w1->len,
- (uchar *)w2->pos,w2->len,0,0);
- }
- static void FT_STOPWORD_free(FT_STOPWORD *w, TREE_FREE action,
- void *arg __attribute__((unused)))
- {
- if (action == free_free)
- my_free((gptr) w->pos, MYF(0));
- }
- static int ft_add_stopword(const char *w)
- {
- FT_STOPWORD sw;
- return !w ||
- (((sw.len= (uint) strlen(sw.pos=w)) >= ft_min_word_len) &&
- (tree_insert(stopwords3, &sw, 0, stopwords3->custom_arg)==NULL));
- }
- int ft_init_stopwords()
- {
- if (!stopwords3)
- {
- if (!(stopwords3=(TREE *)my_malloc(sizeof(TREE),MYF(0))))
- return -1;
- init_tree(stopwords3,0,0,sizeof(FT_STOPWORD),(qsort_cmp2)&FT_STOPWORD_cmp,
- 0,
- (ft_stopword_file ? (tree_element_free)&FT_STOPWORD_free : 0),
- NULL);
- }
- if (ft_stopword_file)
- {
- File fd;
- uint len;
- byte *buffer, *start, *end;
- FT_WORD w;
- int error=-1;
- if (!*ft_stopword_file)
- return 0;
- if ((fd=my_open(ft_stopword_file, O_RDONLY, MYF(MY_WME))) == -1)
- return -1;
- len=(uint)my_seek(fd, 0L, MY_SEEK_END, MYF(0));
- my_seek(fd, 0L, MY_SEEK_SET, MYF(0));
- if (!(start=buffer=my_malloc(len+1, MYF(MY_WME))))
- goto err0;
- len=my_read(fd, buffer, len, MYF(MY_WME));
- end=start+len;
- while (ft_simple_get_word(default_charset_info, &start, end, &w))
- {
- if (ft_add_stopword(my_strdup_with_length(w.pos, w.len, MYF(0))))
- goto err1;
- }
- error=0;
- err1:
- my_free(buffer, MYF(0));
- err0:
- my_close(fd, MYF(MY_WME));
- return error;
- }
- else
- {
- /* compatibility mode: to be removed */
- char **sws=(char **)ft_precompiled_stopwords;
- for (;*sws;sws++)
- {
- if (ft_add_stopword(*sws))
- return -1;
- }
- ft_stopword_file="(built-in)"; /* for SHOW VARIABLES */
- }
- return 0;
- }
- int is_stopword(char *word, uint len)
- {
- FT_STOPWORD sw;
- sw.pos=word;
- sw.len=len;
- return tree_search(stopwords3,&sw, stopwords3->custom_arg) != NULL;
- }
- void ft_free_stopwords()
- {
- if (stopwords3)
- {
- delete_tree(stopwords3); /* purecov: inspected */
- my_free((char*) stopwords3,MYF(0));
- stopwords3=0;
- }
- ft_stopword_file= 0;
- }