Line data Source code
1 : /*-------------------------------------------------------------------------
2 : *
3 : * ts_locale.c
4 : * locale compatibility layer for tsearch
5 : *
6 : * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group
7 : *
8 : *
9 : * IDENTIFICATION
10 : * src/backend/tsearch/ts_locale.c
11 : *
12 : *-------------------------------------------------------------------------
13 : */
14 : #include "postgres.h"
15 :
16 : #include "common/string.h"
17 : #include "storage/fd.h"
18 : #include "tsearch/ts_locale.h"
19 :
20 : static void tsearch_readline_callback(void *arg);
21 :
22 :
23 : /* space for a single character plus a trailing NUL */
24 : #define WC_BUF_LEN 2
25 :
26 : #define GENERATE_T_ISCLASS_DEF(character_class) \
27 : /* mblen shall be that of the first character */ \
28 : int \
29 : t_is##character_class##_with_len(const char *ptr, int mblen) \
30 : { \
31 : pg_wchar wstr[WC_BUF_LEN]; \
32 : int wlen pg_attribute_unused(); \
33 : wlen = pg_mb2wchar_with_len(ptr, wstr, mblen); \
34 : Assert(wlen <= 1); \
35 : /* pass single character, or NUL if empty */ \
36 : return pg_isw##character_class(wstr[0], pg_database_locale()); \
37 : } \
38 : \
39 : /* ptr shall point to a NUL-terminated string */ \
40 : int \
41 : t_is##character_class##_cstr(const char *ptr) \
42 : { \
43 : return t_is##character_class##_with_len(ptr, pg_mblen_cstr(ptr)); \
44 : } \
45 : /* ptr shall point to a string with pre-validated encoding */ \
46 : int \
47 : t_is##character_class##_unbounded(const char *ptr) \
48 : { \
49 : return t_is##character_class##_with_len(ptr, pg_mblen_unbounded(ptr)); \
50 : } \
51 : /* historical name for _unbounded */ \
52 : int \
53 : t_is##character_class(const char *ptr) \
54 : { \
55 : return t_is##character_class##_unbounded(ptr); \
56 : }
57 :
58 1652955 : GENERATE_T_ISCLASS_DEF(alnum)
59 10284 : GENERATE_T_ISCLASS_DEF(alpha)
60 :
61 : /*
62 : * Set up to read a file using tsearch_readline(). This facility is
63 : * better than just reading the file directly because it provides error
64 : * context pointing to the specific line where a problem is detected.
65 : *
66 : * Expected usage is:
67 : *
68 : * tsearch_readline_state trst;
69 : *
70 : * if (!tsearch_readline_begin(&trst, filename))
71 : * ereport(ERROR,
72 : * (errcode(ERRCODE_CONFIG_FILE_ERROR),
73 : * errmsg("could not open stop-word file \"%s\": %m",
74 : * filename)));
75 : * while ((line = tsearch_readline(&trst)) != NULL)
76 : * process line;
77 : * tsearch_readline_end(&trst);
78 : *
79 : * Note that the caller supplies the ereport() for file open failure;
80 : * this is so that a custom message can be provided. The filename string
81 : * passed to tsearch_readline_begin() must remain valid through
82 : * tsearch_readline_end().
83 : */
84 : bool
85 278 : tsearch_readline_begin(tsearch_readline_state *stp,
86 : const char *filename)
87 : {
88 278 : if ((stp->fp = AllocateFile(filename, "r")) == NULL)
89 0 : return false;
90 278 : stp->filename = filename;
91 278 : stp->lineno = 0;
92 278 : initStringInfo(&stp->buf);
93 278 : stp->curline = NULL;
94 : /* Setup error traceback support for ereport() */
95 278 : stp->cb.callback = tsearch_readline_callback;
96 278 : stp->cb.arg = stp;
97 278 : stp->cb.previous = error_context_stack;
98 278 : error_context_stack = &stp->cb;
99 278 : return true;
100 : }
101 :
102 : /*
103 : * Read the next line from a tsearch data file (expected to be in UTF-8), and
104 : * convert it to database encoding if needed. The returned string is palloc'd.
105 : * NULL return means EOF.
106 : */
107 : char *
108 12733 : tsearch_readline(tsearch_readline_state *stp)
109 : {
110 : char *recoded;
111 :
112 : /* Advance line number to use in error reports */
113 12733 : stp->lineno++;
114 :
115 : /* Clear curline, it's no longer relevant */
116 12733 : if (stp->curline)
117 : {
118 12455 : if (stp->curline != stp->buf.data)
119 0 : pfree(stp->curline);
120 12455 : stp->curline = NULL;
121 : }
122 :
123 : /* Collect next line, if there is one */
124 12733 : if (!pg_get_line_buf(stp->fp, &stp->buf))
125 235 : return NULL;
126 :
127 : /* Validate the input as UTF-8, then convert to DB encoding if needed */
128 12498 : recoded = pg_any_to_server(stp->buf.data, stp->buf.len, PG_UTF8);
129 :
130 : /* Save the correctly-encoded string for possible error reports */
131 12498 : stp->curline = recoded; /* might be equal to buf.data */
132 :
133 : /*
134 : * We always return a freshly pstrdup'd string. This is clearly necessary
135 : * if pg_any_to_server() returned buf.data, and we need a second copy even
136 : * if encoding conversion did occur. The caller is entitled to pfree the
137 : * returned string at any time, which would leave curline pointing to
138 : * recycled storage, causing problems if an error occurs after that point.
139 : * (It's preferable to return the result of pstrdup instead of the output
140 : * of pg_any_to_server, because the conversion result tends to be
141 : * over-allocated. Since callers might save the result string directly
142 : * into a long-lived dictionary structure, we don't want it to be a larger
143 : * palloc chunk than necessary. We'll reclaim the conversion result on
144 : * the next call.)
145 : */
146 12498 : return pstrdup(recoded);
147 : }
148 :
149 : /*
150 : * Close down after reading a file with tsearch_readline()
151 : */
152 : void
153 278 : tsearch_readline_end(tsearch_readline_state *stp)
154 : {
155 : /* Suppress use of curline in any error reported below */
156 278 : if (stp->curline)
157 : {
158 43 : if (stp->curline != stp->buf.data)
159 0 : pfree(stp->curline);
160 43 : stp->curline = NULL;
161 : }
162 :
163 : /* Release other resources */
164 278 : pfree(stp->buf.data);
165 278 : FreeFile(stp->fp);
166 :
167 : /* Pop the error context stack */
168 278 : error_context_stack = stp->cb.previous;
169 278 : }
170 :
171 : /*
172 : * Error context callback for errors occurring while reading a tsearch
173 : * configuration file.
174 : */
175 : static void
176 0 : tsearch_readline_callback(void *arg)
177 : {
178 0 : tsearch_readline_state *stp = (tsearch_readline_state *) arg;
179 :
180 : /*
181 : * We can't include the text of the config line for errors that occur
182 : * during tsearch_readline() itself. The major cause of such errors is
183 : * encoding violations, and we daren't try to print error messages
184 : * containing badly-encoded data.
185 : */
186 0 : if (stp->curline)
187 0 : errcontext("line %d of configuration file \"%s\": \"%s\"",
188 : stp->lineno,
189 : stp->filename,
190 : stp->curline);
191 : else
192 0 : errcontext("line %d of configuration file \"%s\"",
193 : stp->lineno,
194 : stp->filename);
195 0 : }
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