1 /*-------------------------------------------------------------------------
4 * Functions for parsing timezone offset files
6 * Note: we generally should not throw any errors in this file, but instead
7 * try to return an error code. This is not completely bulletproof at
8 * present --- in particular out-of-memory will throw an error. Could
9 * probably fix with PG_TRY if necessary.
12 * Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
13 * Portions Copyright (c) 1994, Regents of the University of California
16 * $PostgreSQL: pgsql/src/backend/utils/misc/tzparser.c,v 1.6 2008/01/01 19:45:54 momjian Exp $
18 *-------------------------------------------------------------------------
25 #include "miscadmin.h"
26 #include "storage/fd.h"
27 #include "utils/datetime.h"
28 #include "utils/memutils.h"
29 #include "utils/tzparser.h"
32 #define WHITESPACE " \t\n\r"
34 static int tz_elevel; /* to avoid passing this around a lot */
36 static bool validateTzEntry(tzEntry *tzentry);
37 static bool splitTzLine(const char *filename, int lineno,
38 char *line, tzEntry *tzentry);
39 static int addToArray(tzEntry **base, int *arraysize, int n,
40 tzEntry *entry, bool override);
41 static int ParseTzFile(const char *filename, int depth,
42 tzEntry **base, int *arraysize, int n);
46 * Apply additional validation checks to a tzEntry
48 * Returns TRUE if OK, else false
51 validateTzEntry(tzEntry *tzentry)
56 * Check restrictions imposed by datetkntbl storage format (see
59 if (strlen(tzentry->abbrev) > TOKMAXLEN)
62 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
63 errmsg("time zone abbreviation \"%s\" is too long (maximum %d characters) in time zone file \"%s\", line %d",
64 tzentry->abbrev, TOKMAXLEN,
65 tzentry->filename, tzentry->lineno)));
68 if (tzentry->offset % 900 != 0)
71 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
72 errmsg("time zone offset %d is not a multiple of 900 sec (15 min) in time zone file \"%s\", line %d",
74 tzentry->filename, tzentry->lineno)));
79 * Sanity-check the offset: shouldn't exceed 14 hours
81 if (tzentry->offset > 14 * 60 * 60 ||
82 tzentry->offset < -14 * 60 * 60)
85 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
86 errmsg("time zone offset %d is out of range in time zone file \"%s\", line %d",
88 tzentry->filename, tzentry->lineno)));
93 * Convert abbrev to lowercase (must match datetime.c's conversion)
95 for (p = (unsigned char *) tzentry->abbrev; *p; p++)
102 * Attempt to parse the line as a timezone abbrev spec (name, offset, dst)
104 * Returns TRUE if OK, else false; data is stored in *tzentry
107 splitTzLine(const char *filename, int lineno, char *line, tzEntry *tzentry)
115 tzentry->lineno = lineno;
116 tzentry->filename = filename;
118 abbrev = strtok(line, WHITESPACE);
122 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
123 errmsg("missing time zone abbreviation in time zone file \"%s\", line %d",
127 tzentry->abbrev = abbrev;
129 offset = strtok(NULL, WHITESPACE);
133 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
134 errmsg("missing time zone offset in time zone file \"%s\", line %d",
138 tzentry->offset = strtol(offset, &offset_endptr, 10);
139 if (offset_endptr == offset || *offset_endptr != '\0')
142 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
143 errmsg("invalid number for time zone offset in time zone file \"%s\", line %d",
148 is_dst = strtok(NULL, WHITESPACE);
149 if (is_dst && pg_strcasecmp(is_dst, "D") == 0)
151 tzentry->is_dst = true;
152 remain = strtok(NULL, WHITESPACE);
156 /* there was no 'D' dst specifier */
157 tzentry->is_dst = false;
161 if (!remain) /* no more non-whitespace chars */
164 if (remain[0] != '#') /* must be a comment */
167 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
168 errmsg("invalid syntax in time zone file \"%s\", line %d",
176 * Insert entry into sorted array
178 * *base: base address of array (changeable if must enlarge array)
179 * *arraysize: allocated length of array (changeable if must enlarge array)
180 * n: current number of valid elements in array
181 * entry: new data to insert
182 * override: TRUE if OK to override
184 * Returns the new array length (new value for n), or -1 if error
187 addToArray(tzEntry **base, int *arraysize, int n,
188 tzEntry *entry, bool override)
195 * Search the array for a duplicate; as a useful side effect, the array is
196 * maintained in sorted order. We use strcmp() to ensure we match the
197 * sort order datetime.c expects.
204 int mid = (low + high) >> 1;
205 tzEntry *midptr = arrayptr + mid;
208 cmp = strcmp(entry->abbrev, midptr->abbrev);
216 * Found a duplicate entry; complain unless it's the same.
218 if (midptr->offset == entry->offset &&
219 midptr->is_dst == entry->is_dst)
221 /* return unchanged array */
226 /* same abbrev but something is different, override */
227 midptr->offset = entry->offset;
228 midptr->is_dst = entry->is_dst;
231 /* same abbrev but something is different, complain */
233 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
234 errmsg("time zone abbreviation \"%s\" is multiply defined",
236 errdetail("Entry in time zone file \"%s\", line %d, conflicts with entry in file \"%s\", line %d.",
237 midptr->filename, midptr->lineno,
238 entry->filename, entry->lineno)));
244 * No match, insert at position "low".
249 *base = (tzEntry *) repalloc(*base, *arraysize * sizeof(tzEntry));
252 arrayptr = *base + low;
254 memmove(arrayptr + 1, arrayptr, (n - low) * sizeof(tzEntry));
256 memcpy(arrayptr, entry, sizeof(tzEntry));
258 /* Must dup the abbrev to ensure it survives */
259 arrayptr->abbrev = pstrdup(entry->abbrev);
265 * Parse a single timezone abbrev file --- can recurse to handle @INCLUDE
267 * filename: user-specified file name (does not include path)
268 * depth: current recursion depth
269 * *base: array for results (changeable if must enlarge array)
270 * *arraysize: allocated length of array (changeable if must enlarge array)
271 * n: current number of valid elements in array
273 * Returns the new array length (new value for n), or -1 if error
276 ParseTzFile(const char *filename, int depth,
277 tzEntry **base, int *arraysize, int n)
279 char share_path[MAXPGPATH];
280 char file_path[MAXPGPATH];
286 bool override = false;
290 * We enforce that the filename is all alpha characters. This may be
291 * overly restrictive, but we don't want to allow access to anything
292 * outside the timezonesets directory, so for instance '/' *must* be
295 for (p = filename; *p; p++)
297 if (!isalpha((unsigned char) *p))
299 /* at level 0, we need no ereport since guc.c will say enough */
302 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
303 errmsg("invalid time zone file name \"%s\"",
310 * The maximal recursion depth is a pretty arbitrary setting. It is hard
311 * to imagine that someone needs more than 3 levels so stick with this
312 * conservative setting until someone complains.
317 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
318 errmsg("time zone file recursion limit exceeded in file \"%s\"",
323 get_share_path(my_exec_path, share_path);
324 snprintf(file_path, sizeof(file_path), "%s/timezonesets/%s",
325 share_path, filename);
326 tzFile = AllocateFile(file_path, "r");
329 /* at level 0, if file doesn't exist, guc.c's complaint is enough */
330 if (errno != ENOENT || depth > 0)
332 (errcode_for_file_access(),
333 errmsg("could not read time zone file \"%s\": %m",
338 while (!feof(tzFile))
341 if (fgets(tzbuf, sizeof(tzbuf), tzFile) == NULL)
346 (errcode_for_file_access(),
347 errmsg("could not read time zone file \"%s\": %m",
351 /* else we're at EOF after all */
354 if (strlen(tzbuf) == sizeof(tzbuf) - 1)
356 /* the line is too long for tzbuf */
358 (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
359 errmsg("line is too long in time zone file \"%s\", line %d",
364 /* skip over whitespace */
366 while (*line && isspace((unsigned char) *line))
369 if (*line == '\0') /* empty line */
371 if (*line == '#') /* comment line */
374 if (pg_strncasecmp(line, "@INCLUDE", strlen("@INCLUDE")) == 0)
376 /* pstrdup so we can use filename in result data structure */
377 char *includeFile = pstrdup(line + strlen("@INCLUDE"));
379 includeFile = strtok(includeFile, WHITESPACE);
380 if (!includeFile || !*includeFile)
383 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
384 errmsg("@INCLUDE without file name in time zone file \"%s\", line %d",
388 n = ParseTzFile(includeFile, depth + 1,
395 if (pg_strncasecmp(line, "@OVERRIDE", strlen("@OVERRIDE")) == 0)
401 if (!splitTzLine(filename, lineno, line, &tzentry))
403 if (!validateTzEntry(&tzentry))
405 n = addToArray(base, arraysize, n, &tzentry, override);
416 * load_tzoffsets --- read and parse the specified timezone offset file
418 * filename: name specified by user
419 * doit: whether to actually apply the new values, or just check
420 * elevel: elog reporting level (will be less than ERROR)
422 * Returns TRUE if OK, FALSE if not; should avoid erroring out
425 load_tzoffsets(const char *filename, bool doit, int elevel)
427 MemoryContext tmpContext;
428 MemoryContext oldContext;
436 * Create a temp memory context to work in. This makes it easy to clean
439 tmpContext = AllocSetContextCreate(CurrentMemoryContext,
441 ALLOCSET_SMALL_MINSIZE,
442 ALLOCSET_SMALL_INITSIZE,
443 ALLOCSET_SMALL_MAXSIZE);
444 oldContext = MemoryContextSwitchTo(tmpContext);
446 /* Initialize array at a reasonable size */
448 array = (tzEntry *) palloc(arraysize * sizeof(tzEntry));
450 /* Parse the file(s) */
451 n = ParseTzFile(filename, 0, &array, &arraysize, 0);
453 /* If no errors and we should apply the result, pass it to datetime.c */
455 InstallTimeZoneAbbrevs(array, n);
458 MemoryContextSwitchTo(oldContext);
459 MemoryContextDelete(tmpContext);