diff options
Diffstat (limited to 'libraries/sqlite/win32/fts1_tokenizer1.c')
-rwxr-xr-x | libraries/sqlite/win32/fts1_tokenizer1.c | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/libraries/sqlite/win32/fts1_tokenizer1.c b/libraries/sqlite/win32/fts1_tokenizer1.c new file mode 100755 index 0000000..f58fba8 --- /dev/null +++ b/libraries/sqlite/win32/fts1_tokenizer1.c | |||
@@ -0,0 +1,221 @@ | |||
1 | /* | ||
2 | ** The author disclaims copyright to this source code. | ||
3 | ** | ||
4 | ************************************************************************* | ||
5 | ** Implementation of the "simple" full-text-search tokenizer. | ||
6 | */ | ||
7 | |||
8 | /* | ||
9 | ** The code in this file is only compiled if: | ||
10 | ** | ||
11 | ** * The FTS1 module is being built as an extension | ||
12 | ** (in which case SQLITE_CORE is not defined), or | ||
13 | ** | ||
14 | ** * The FTS1 module is being built into the core of | ||
15 | ** SQLite (in which case SQLITE_ENABLE_FTS1 is defined). | ||
16 | */ | ||
17 | #if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS1) | ||
18 | |||
19 | |||
20 | #include <assert.h> | ||
21 | #include <stdlib.h> | ||
22 | #include <stdio.h> | ||
23 | #include <string.h> | ||
24 | #include <ctype.h> | ||
25 | |||
26 | #include "fts1_tokenizer.h" | ||
27 | |||
28 | typedef struct simple_tokenizer { | ||
29 | sqlite3_tokenizer base; | ||
30 | char delim[128]; /* flag ASCII delimiters */ | ||
31 | } simple_tokenizer; | ||
32 | |||
33 | typedef struct simple_tokenizer_cursor { | ||
34 | sqlite3_tokenizer_cursor base; | ||
35 | const char *pInput; /* input we are tokenizing */ | ||
36 | int nBytes; /* size of the input */ | ||
37 | int iOffset; /* current position in pInput */ | ||
38 | int iToken; /* index of next token to be returned */ | ||
39 | char *pToken; /* storage for current token */ | ||
40 | int nTokenAllocated; /* space allocated to zToken buffer */ | ||
41 | } simple_tokenizer_cursor; | ||
42 | |||
43 | |||
44 | /* Forward declaration */ | ||
45 | static const sqlite3_tokenizer_module simpleTokenizerModule; | ||
46 | |||
47 | static int isDelim(simple_tokenizer *t, unsigned char c){ | ||
48 | return c<0x80 && t->delim[c]; | ||
49 | } | ||
50 | |||
51 | /* | ||
52 | ** Create a new tokenizer instance. | ||
53 | */ | ||
54 | static int simpleCreate( | ||
55 | int argc, const char * const *argv, | ||
56 | sqlite3_tokenizer **ppTokenizer | ||
57 | ){ | ||
58 | simple_tokenizer *t; | ||
59 | |||
60 | t = (simple_tokenizer *) calloc(sizeof(*t), 1); | ||
61 | if( t==NULL ) return SQLITE_NOMEM; | ||
62 | |||
63 | /* TODO(shess) Delimiters need to remain the same from run to run, | ||
64 | ** else we need to reindex. One solution would be a meta-table to | ||
65 | ** track such information in the database, then we'd only want this | ||
66 | ** information on the initial create. | ||
67 | */ | ||
68 | if( argc>1 ){ | ||
69 | int i, n = strlen(argv[1]); | ||
70 | for(i=0; i<n; i++){ | ||
71 | unsigned char ch = argv[1][i]; | ||
72 | /* We explicitly don't support UTF-8 delimiters for now. */ | ||
73 | if( ch>=0x80 ){ | ||
74 | free(t); | ||
75 | return SQLITE_ERROR; | ||
76 | } | ||
77 | t->delim[ch] = 1; | ||
78 | } | ||
79 | } else { | ||
80 | /* Mark non-alphanumeric ASCII characters as delimiters */ | ||
81 | int i; | ||
82 | for(i=1; i<0x80; i++){ | ||
83 | t->delim[i] = !isalnum(i); | ||
84 | } | ||
85 | } | ||
86 | |||
87 | *ppTokenizer = &t->base; | ||
88 | return SQLITE_OK; | ||
89 | } | ||
90 | |||
91 | /* | ||
92 | ** Destroy a tokenizer | ||
93 | */ | ||
94 | static int simpleDestroy(sqlite3_tokenizer *pTokenizer){ | ||
95 | free(pTokenizer); | ||
96 | return SQLITE_OK; | ||
97 | } | ||
98 | |||
99 | /* | ||
100 | ** Prepare to begin tokenizing a particular string. The input | ||
101 | ** string to be tokenized is pInput[0..nBytes-1]. A cursor | ||
102 | ** used to incrementally tokenize this string is returned in | ||
103 | ** *ppCursor. | ||
104 | */ | ||
105 | static int simpleOpen( | ||
106 | sqlite3_tokenizer *pTokenizer, /* The tokenizer */ | ||
107 | const char *pInput, int nBytes, /* String to be tokenized */ | ||
108 | sqlite3_tokenizer_cursor **ppCursor /* OUT: Tokenization cursor */ | ||
109 | ){ | ||
110 | simple_tokenizer_cursor *c; | ||
111 | |||
112 | c = (simple_tokenizer_cursor *) malloc(sizeof(*c)); | ||
113 | if( c==NULL ) return SQLITE_NOMEM; | ||
114 | |||
115 | c->pInput = pInput; | ||
116 | if( pInput==0 ){ | ||
117 | c->nBytes = 0; | ||
118 | }else if( nBytes<0 ){ | ||
119 | c->nBytes = (int)strlen(pInput); | ||
120 | }else{ | ||
121 | c->nBytes = nBytes; | ||
122 | } | ||
123 | c->iOffset = 0; /* start tokenizing at the beginning */ | ||
124 | c->iToken = 0; | ||
125 | c->pToken = NULL; /* no space allocated, yet. */ | ||
126 | c->nTokenAllocated = 0; | ||
127 | |||
128 | *ppCursor = &c->base; | ||
129 | return SQLITE_OK; | ||
130 | } | ||
131 | |||
132 | /* | ||
133 | ** Close a tokenization cursor previously opened by a call to | ||
134 | ** simpleOpen() above. | ||
135 | */ | ||
136 | static int simpleClose(sqlite3_tokenizer_cursor *pCursor){ | ||
137 | simple_tokenizer_cursor *c = (simple_tokenizer_cursor *) pCursor; | ||
138 | free(c->pToken); | ||
139 | free(c); | ||
140 | return SQLITE_OK; | ||
141 | } | ||
142 | |||
143 | /* | ||
144 | ** Extract the next token from a tokenization cursor. The cursor must | ||
145 | ** have been opened by a prior call to simpleOpen(). | ||
146 | */ | ||
147 | static int simpleNext( | ||
148 | sqlite3_tokenizer_cursor *pCursor, /* Cursor returned by simpleOpen */ | ||
149 | const char **ppToken, /* OUT: *ppToken is the token text */ | ||
150 | int *pnBytes, /* OUT: Number of bytes in token */ | ||
151 | int *piStartOffset, /* OUT: Starting offset of token */ | ||
152 | int *piEndOffset, /* OUT: Ending offset of token */ | ||
153 | int *piPosition /* OUT: Position integer of token */ | ||
154 | ){ | ||
155 | simple_tokenizer_cursor *c = (simple_tokenizer_cursor *) pCursor; | ||
156 | simple_tokenizer *t = (simple_tokenizer *) pCursor->pTokenizer; | ||
157 | unsigned char *p = (unsigned char *)c->pInput; | ||
158 | |||
159 | while( c->iOffset<c->nBytes ){ | ||
160 | int iStartOffset; | ||
161 | |||
162 | /* Scan past delimiter characters */ | ||
163 | while( c->iOffset<c->nBytes && isDelim(t, p[c->iOffset]) ){ | ||
164 | c->iOffset++; | ||
165 | } | ||
166 | |||
167 | /* Count non-delimiter characters. */ | ||
168 | iStartOffset = c->iOffset; | ||
169 | while( c->iOffset<c->nBytes && !isDelim(t, p[c->iOffset]) ){ | ||
170 | c->iOffset++; | ||
171 | } | ||
172 | |||
173 | if( c->iOffset>iStartOffset ){ | ||
174 | int i, n = c->iOffset-iStartOffset; | ||
175 | if( n>c->nTokenAllocated ){ | ||
176 | c->nTokenAllocated = n+20; | ||
177 | c->pToken = realloc(c->pToken, c->nTokenAllocated); | ||
178 | if( c->pToken==NULL ) return SQLITE_NOMEM; | ||
179 | } | ||
180 | for(i=0; i<n; i++){ | ||
181 | /* TODO(shess) This needs expansion to handle UTF-8 | ||
182 | ** case-insensitivity. | ||
183 | */ | ||
184 | unsigned char ch = p[iStartOffset+i]; | ||
185 | c->pToken[i] = ch<0x80 ? tolower(ch) : ch; | ||
186 | } | ||
187 | *ppToken = c->pToken; | ||
188 | *pnBytes = n; | ||
189 | *piStartOffset = iStartOffset; | ||
190 | *piEndOffset = c->iOffset; | ||
191 | *piPosition = c->iToken++; | ||
192 | |||
193 | return SQLITE_OK; | ||
194 | } | ||
195 | } | ||
196 | return SQLITE_DONE; | ||
197 | } | ||
198 | |||
199 | /* | ||
200 | ** The set of routines that implement the simple tokenizer | ||
201 | */ | ||
202 | static const sqlite3_tokenizer_module simpleTokenizerModule = { | ||
203 | 0, | ||
204 | simpleCreate, | ||
205 | simpleDestroy, | ||
206 | simpleOpen, | ||
207 | simpleClose, | ||
208 | simpleNext, | ||
209 | }; | ||
210 | |||
211 | /* | ||
212 | ** Allocate a new simple tokenizer. Return a pointer to the new | ||
213 | ** tokenizer in *ppModule | ||
214 | */ | ||
215 | void sqlite3Fts1SimpleTokenizerModule( | ||
216 | sqlite3_tokenizer_module const**ppModule | ||
217 | ){ | ||
218 | *ppModule = &simpleTokenizerModule; | ||
219 | } | ||
220 | |||
221 | #endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS1) */ | ||