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Diffstat (limited to 'libkcal/libical/vzic-1.3/vzic-output.c')
| -rw-r--r-- | libkcal/libical/vzic-1.3/vzic-output.c | 2325 |
1 files changed, 2325 insertions, 0 deletions
diff --git a/libkcal/libical/vzic-1.3/vzic-output.c b/libkcal/libical/vzic-1.3/vzic-output.c new file mode 100644 index 00000000..a23ece13 --- /dev/null +++ b/libkcal/libical/vzic-1.3/vzic-output.c @@ -0,0 +1,2325 @@ +/* + * Vzic - a program to convert Olson timezone database files into VZTIMEZONE + * files compatible with the iCalendar specification (RFC2445). + * + * Copyright (C) 2000-2001 Ximian, Inc. + * Copyright (C) 2003 Damon Chaplin. + * + * Author: Damon Chaplin <damon@gnome.org> + * + * 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. + */ + +/* ALGORITHM: + * + * First we expand all the Rule arrays, so that each element only represents 1 + * year. If a Rule extends to infinity we expand it up to a few years past the + * maximum UNTIL year used in any of the timezones. We do this to make sure + * that the last of the expanded Rules (which may be infinite) is only used + * in the last of the time periods (i.e. the last Zone line). + * + * The Rule arrays are also sorted by the start time (FROM + IN + ON + AT). + * Doing all this makes it much easier to find which rules apply to which + * periods. + * + * For each timezone (i.e. ZoneData element), we step through each of the + * time periods, the ZoneLineData elements (which represent each Zone line + * from the Olson file.) + * + * We calculate the start & end time of the period. + * - For the first line the start time is -infinity. + * - For the last line the end time is +infinity. + * - The end time of each line is also the start time of the next. + * + * We create an array of time changes which occur in this period, including + * the one implied by the Zone line itself (though this is later taken out + * if it is found to be at exactly the same time as the first Rule). + * + * Now we iterate over the time changes, outputting them as STANDARD or + * DAYLIGHT components. We also try to merge them together into RRULEs or + * use RDATEs. + */ + + +#include <errno.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <time.h> +#include <sys/stat.h> +#include <unistd.h> + +#include "vzic.h" +#include "vzic-output.h" + +#include "vzic-dump.h" + + +/* These come from the Makefile. See the comments there. */ +char *ProductID = PRODUCT_ID; +char *TZIDPrefix = TZID_PREFIX; + +/* We expand the TZIDPrefix, replacing %D with the date, in here. */ +char TZIDPrefixExpanded[1024]; + + +/* We only use RRULEs if there are at least MIN_RRULE_OCCURRENCES occurrences, + since otherwise RDATEs are more efficient. Actually, I've set this high + so we only use RRULEs for infinite recurrences. Since expanding RRULEs is + very time-consuming, this seems sensible. */ +#define MIN_RRULE_OCCURRENCES 100 + + +/* The year we go up to when dumping the list of timezone changes (used + for testing & debugging). */ +#define MAX_CHANGES_YEAR 2030 + +/* This is the maximum year that time_t value can typically hold on 32-bit + systems. */ +#define MAX_TIME_T_YEAR 2037 + + +/* The year we use to start RRULEs. */ +#define RRULE_START_YEAR 1970 + +/* The year we use for RDATEs. */ +#define RDATE_YEAR 1970 + + +static char *WeekDays[] = { "SU", "MO", "TU", "WE", "TH", "FR", "SA" }; +static int DaysInMonth[] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }; + +char *CurrentZoneName; + + +typedef struct _VzicTime VzicTime; +struct _VzicTime +{ + /* Normal years, e.g. 2001. */ + int year; + + /* 0 (Jan) to 11 (Dec). */ + int month; + + /* The day, either a simple month day number, 1-31, or a rule such as + the last Sunday, or the first Monday on or after the 8th. */ + DayCode day_code; + int day_number; /* 1 to 31. */ + int day_weekday; /* 0 (Sun) to 6 (Sat). */ + + /* The time, in seconds from midnight. The code specifies whether the + time is a wall clock time, local standard time, or universal time. */ + int time_seconds; + TimeCode time_code; + + /* The offset from UTC for local standard time. */ + int stdoff; + + /* The offset from UTC for local wall clock time. If this is different to + stdoff then this is a DAYLIGHT component. This is TZOFFSETTO. */ + int walloff; + + /* TRUE if the time change recurs every year to infinity. */ + gboolean is_infinite; + + /* TRUE if the change has already been output. */ + gboolean output; + + /* These are the offsets of the previous VzicTime, and are used when + calculating the time of the change. We place them here in + output_zone_components() to simplify the output code. */ + int prev_stdoff; + int prev_walloff; + + /* The abbreviated form of the timezone name. Note that this may not be + unique. */ + char *tzname; +}; + + +static void expand_and_sort_rule_array (gpointer key, + gpointer value, + gpointer data); +static int rule_sort_func (const void *arg1, + const void *arg2); +static void output_zone (char *directory, + ZoneData *zone, + char *zone_name, + GHashTable *rule_data); +static gboolean parse_zone_name (char *name, + char **directory, + char **subdirectory, + char **filename); +static void output_zone_to_files (ZoneData *zone, + char *zone_name, + GHashTable *rule_data, + FILE *fp, + FILE *changes_fp); +static gboolean add_rule_changes (ZoneLineData *zone_line, + char *zone_name, + GArray *changes, + GHashTable *rule_data, + VzicTime *start, + VzicTime *end, + char **start_letter_s, + int *save_seconds); +static char* expand_tzname (char *zone_name, + char *format, + gboolean have_letter_s, + char *letter_s, + gboolean is_daylight); +static int compare_times (VzicTime *time1, + int stdoff1, + int walloff1, + VzicTime *time2, + int stdoff2, + int walloff2); +static gboolean times_match (VzicTime *time1, + int stdoff1, + int walloff1, + VzicTime *time2, + int stdoff2, + int walloff2); +static void output_zone_components (FILE *fp, + char *name, + GArray *changes); +static void set_previous_offsets (GArray *changes); +static gboolean check_for_recurrence (FILE *fp, + GArray *changes, + int idx); +static void check_for_rdates (FILE *fp, + GArray *changes, + int idx); +static gboolean timezones_match (char *tzname1, + char *tzname2); +static int output_component_start (char *buffer, + VzicTime *vzictime, + gboolean output_rdate, + gboolean use_same_tz_offset); +static void output_component_end (FILE *fp, + VzicTime *vzictime); + +static void vzictime_init (VzicTime *vzictime); +static int calculate_actual_time (VzicTime *vzictime, + TimeCode time_code, + int stdoff, + int walloff); +static int calculate_wall_time (int time, + TimeCode time_code, + int stdoff, + int walloff, + int *day_offset); +static int calculate_until_time (int time, + TimeCode time_code, + int stdoff, + int walloff, + int *year, + int *month, + int *day); +static void fix_time_overflow (int *year, + int *month, + int *day, + int day_offset); + +static char* format_time (int year, + int month, + int day, + int time); +static char* format_tz_offset (int tz_offset, + gboolean round_seconds); +static gboolean output_rrule (char *rrule_buffer, + int month, + DayCode day_code, + int day_number, + int day_weekday, + int day_offset, + char *until); +static gboolean output_rrule_2 (char *buffer, + int month, + int day_number, + int day_weekday); + +static char* format_vzictime (VzicTime *vzictime); + +static void dump_changes (FILE *fp, + char *zone_name, + GArray *changes); +static void dump_change (FILE *fp, + char *zone_name, + VzicTime *vzictime, + int year); + +static void expand_tzid_prefix (void); + + +void +output_vtimezone_files (char *directory, + GArray *zone_data, + GHashTable *rule_data, + GHashTable *link_data, + int max_until_year) +{ + ZoneData *zone; + GList *links; + char *link_to; + int i; + + /* Insert today's date into the TZIDs we output. */ + expand_tzid_prefix (); + + /* Expand the rule data so that each entry specifies only one year, and + sort it so we can easily find the rules applicable to each Zone span. */ + g_hash_table_foreach (rule_data, expand_and_sort_rule_array, + GINT_TO_POINTER (max_until_year)); + + /* Output each timezone. */ + for (i = 0; i < zone_data->len; i++) { + zone = &g_array_index (zone_data, ZoneData, i); + output_zone (directory, zone, zone->zone_name, rule_data); + + /* Look for any links from this zone. */ + links = g_hash_table_lookup (link_data, zone->zone_name); + + while (links) { + link_to = links->data; + + /* We ignore Links that don't have a '/' in them (things like 'EST5EDT'). + */ + if (strchr (link_to, '/')) { + output_zone (directory, zone, link_to, rule_data); + } + + links = links->next; + } + } +} + + +static void +expand_and_sort_rule_array (gpointer key, + gpointer value, + gpointer data) +{ + char *name = key; + GArray *rule_array = value; + RuleData *rule, tmp_rule; + int len, max_year, i, from, to, year; + gboolean is_infinite; + + /* We expand the rule data to a year greater than any year used in a Zone + UNTIL value. This is so that we can easily get parts of the array to + use for each Zone line. */ + max_year = GPOINTER_TO_INT (data) + 2; + + /* If any of the rules apply to several years, we turn it into a single rule + for each year. If the Rule is infinite we go up to max_year. + We change the FROM field in the copies of the Rule, setting it to each + of the years, and set TO to FROM, except if TO was YEAR_MAXIMUM we set + the last TO to YEAR_MAXIMUM, so we still know the Rule is infinite. */ + len = rule_array->len; + for (i = 0; i < len; i++) { + rule = &g_array_index (rule_array, RuleData, i); + + /* None of the Rules currently use the TYPE field, but we'd better check. + */ + if (rule->type) { + fprintf (stderr, "Rules %s has a TYPE: %s\n", name, rule->type); + exit (1); + } + + if (rule->from_year != rule->to_year) { + from = rule->from_year; + to = rule->to_year; + + tmp_rule = *rule; + + /* Flag that this is a shallow copy so we don't free anything twice. */ + tmp_rule.is_shallow_copy = TRUE; + + /* See if it is an infinite Rule. */ + if (to == YEAR_MAXIMUM) { + is_infinite = TRUE; + to = max_year; + if (from < to) + rule->to_year = rule->from_year; + } else { + is_infinite = FALSE; + } + + /* Create a copy of the Rule for each year. */ + for (year = from + 1; year <= to; year++) { + tmp_rule.from_year = year; + + /* If the Rule is infinite, mark the last copy as infinite. */ + if (year == to && is_infinite) + tmp_rule.to_year = YEAR_MAXIMUM; + else + tmp_rule.to_year = year; + + g_array_append_val (rule_array, tmp_rule); + } + } + } + + /* Now sort the rules. */ + qsort (rule_array->data, rule_array->len, sizeof (RuleData), rule_sort_func); + +#if 0 + dump_rule_array (name, rule_array, stdout); +#endif +} + + +/* This is used to sort the rules, after the rules have all been expanded so + that each one is only for one year. */ +static int +rule_sort_func (const void *arg1, + const void *arg2) +{ + RuleData *rule1, *rule2; + int time1_year, time1_month, time1_day; + int time2_year, time2_month, time2_day; + int month_diff, result; + VzicTime t1, t2; + + rule1 = (RuleData*) arg1; + rule2 = (RuleData*) arg2; + + time1_year = rule1->from_year; + time1_month = rule1->in_month; + time2_year = rule2->from_year; + time2_month = rule2->in_month; + + /* If there is more that one month difference we don't need to calculate + the day or time. */ + month_diff = (time1_year - time2_year) * 12 + time1_month - time2_month; + + if (month_diff > 1) + return 1; + if (month_diff < -1) + return -1; + + /* Now we have to calculate the day and time of the Rule start and the + VzicTime, using the given offsets. */ + t1.year = time1_year; + t1.month = time1_month; + t1.day_code = rule1->on_day_code; + t1.day_number = rule1->on_day_number; + t1.day_weekday = rule1->on_day_weekday; + t1.time_code = rule1->at_time_code; + t1.time_seconds = rule1->at_time_seconds; + + t2.year = time2_year; + t2.month = time2_month; + t2.day_code = rule2->on_day_code; + t2.day_number = rule2->on_day_number; + t2.day_weekday = rule2->on_day_weekday; + t2.time_code = rule2->at_time_code; + t2.time_seconds = rule2->at_time_seconds; + + /* FIXME: We don't know the offsets yet, but I don't think any Rules are + close enough together that the offsets can make a difference. Should + check this. */ + calculate_actual_time (&t1, TIME_WALL, 0, 0); + calculate_actual_time (&t2, TIME_WALL, 0, 0); + + /* Now we can compare the entire time. */ + if (t1.year > t2.year) + result = 1; + else if (t1.year < t2.year) + result = -1; + + else if (t1.month > t2.month) + result = 1; + else if (t1.month < t2.month) + result = -1; + + else if (t1.day_number > t2.day_number) + result = 1; + else if (t1.day_number < t2.day_number) + result = -1; + + else if (t1.time_seconds > t2.time_seconds) + result = 1; + else if (t1.time_seconds < t2.time_seconds) + result = -1; + + else { + printf ("WARNING: Rule dates matched.\n"); + result = 0; + } + + return result; +} + + +static void +output_zone (char *directory, + ZoneData *zone, + char *zone_name, + GHashTable *rule_data) +{ + FILE *fp, *changes_fp = NULL; + char output_directory[PATHNAME_BUFFER_SIZE]; + char filename[PATHNAME_BUFFER_SIZE]; + char changes_filename[PATHNAME_BUFFER_SIZE]; + char *zone_directory, *zone_subdirectory, *zone_filename; + + /* Set a global for the zone_name, to be used only for debug messages. */ + CurrentZoneName = zone_name; + + /* Use this to only output a particular zone. */ +#if 0 + if (strcmp (zone_name, "Atlantic/Azores")) + return; +#endif + +#if 0 + printf ("Outputting Zone: %s\n", zone_name); +#endif + + if (!parse_zone_name (zone_name, &zone_directory, &zone_subdirectory, + &zone_filename)) + return; + + if (VzicDumpZoneNamesAndCoords) { + VzicTimeZoneNames = g_list_prepend (VzicTimeZoneNames, + g_strdup (zone_name)); + } + + sprintf (output_directory, "%s/%s", directory, zone_directory); + ensure_directory_exists (output_directory); + sprintf (filename, "%s/%s.ics", output_directory, zone_filename); + + if (VzicDumpChanges) { + sprintf (output_directory, "%s/ChangesVzic/%s", directory, zone_directory); + ensure_directory_exists (output_directory); + sprintf (changes_filename, "%s/%s", output_directory, zone_filename); + } + + if (zone_subdirectory) { + sprintf (output_directory, "%s/%s/%s", directory, zone_directory, + zone_subdirectory); + ensure_directory_exists (output_directory); + sprintf (filename, "%s/%s.ics", output_directory, zone_filename); + + if (VzicDumpChanges) { + sprintf (output_directory, "%s/ChangesVzic/%s/%s", directory, + zone_directory, zone_subdirectory); + ensure_directory_exists (output_directory); + sprintf (changes_filename, "%s/%s", output_directory, zone_filename); + } + } + + /* Create the files. */ + fp = fopen (filename, "w"); + if (!fp) { + fprintf (stderr, "Couldn't create file: %s\n", filename); + exit (1); + } + + if (VzicDumpChanges) { + changes_fp = fopen (changes_filename, "w"); + if (!changes_fp) { + fprintf (stderr, "Couldn't create file: %s\n", changes_filename); + exit (1); + } + } + + fprintf (fp, "BEGIN:VCALENDAR\nPRODID:%s\nVERSION:2.0\n", ProductID); + + output_zone_to_files (zone, zone_name, rule_data, fp, changes_fp); + + if (ferror (fp)) { + fprintf (stderr, "Error writing file: %s\n", filename); + exit (1); + } + + fprintf (fp, "END:VCALENDAR\n"); + + fclose (fp); + + g_free (zone_directory); + g_free (zone_subdirectory); + g_free (zone_filename); +} + + +/* This checks that the Zone name only uses the characters in [-+_/a-zA-Z0-9], + and outputs a warning if it isn't. */ +static gboolean +parse_zone_name (char *name, + char **directory, + char **subdirectory, + char **filename) +{ + static int invalid_zone_num = 1; + + char *p, ch, *first_slash_pos = NULL, *second_slash_pos = NULL; + gboolean invalid = FALSE; + + for (p = name; (ch = *p) != 0; p++) { + if ((ch < 'a' || ch > 'z') && (ch < 'A' || ch > 'Z') + && (ch < '0' || ch > '9') && ch != '/' && ch != '_' + && ch != '-' && ch != '+') { + fprintf (stderr, "WARNING: Unusual Zone name: %s\n", name); + invalid = TRUE; + break; + } + + if (ch == '/') { + if (!first_slash_pos) { + first_slash_pos = p; + } else if (!second_slash_pos) { + second_slash_pos = p; + } else { + fprintf (stderr, "WARNING: More than 2 '/' characters in Zone name: %s\n", name); + invalid = TRUE; + break; + } + } + } + + if (!first_slash_pos) { +#if 0 + fprintf (stderr, "No '/' character in Zone name: %s. Skipping.\n", name); +#endif + return FALSE; + } + + if (invalid) { + *directory = g_strdup ("Invalid"); + *filename = g_strdup_printf ("Zone%i", invalid_zone_num++); + } else { + *first_slash_pos = '\0'; + *directory = g_strdup (name); + *first_slash_pos = '/'; + + if (second_slash_pos) { + *second_slash_pos = '\0'; + *subdirectory = g_strdup (first_slash_pos + 1); + *second_slash_pos = '/'; + + *filename = g_strdup (second_slash_pos + 1); + } else { + *subdirectory = NULL; + *filename = g_strdup (first_slash_pos + 1); + } + } + + return invalid ? FALSE : TRUE; +} + + +static void +output_zone_to_files (ZoneData *zone, + char *zone_name, + GHashTable *rule_data, + FILE *fp, + FILE *changes_fp) +{ + ZoneLineData *zone_line; + GArray *changes; + int i, stdoff, walloff, start_index, save_seconds; + VzicTime start, end, *vzictime_start, *vzictime, *vzictime_first_rule_change; + gboolean is_daylight, found_letter_s; + char *start_letter_s; + + changes = g_array_new (FALSE, FALSE, sizeof (VzicTime)); + + vzictime_init (&start); + vzictime_init (&end); + + /* The first period starts at -infinity. */ + start.year = YEAR_MINIMUM; + + for (i = 0; i < zone->zone_line_data->len; i++) { + zone_line = &g_array_index (zone->zone_line_data, ZoneLineData, i); + + /* This is the local standard time offset from GMT for this period. */ + start.stdoff = stdoff = zone_line->stdoff_seconds; + start.walloff = walloff = stdoff + zone_line->save_seconds; + + if (zone_line->until_set) { + end.year = zone_line->until_year; + end.month = zone_line->until_month; + end.day_code = zone_line->until_day_code; + end.day_number = zone_line->until_day_number; + end.day_weekday = zone_line->until_day_weekday; + end.time_seconds = zone_line->until_time_seconds; + end.time_code = zone_line->until_time_code; + } else { + /* The last period ends at +infinity. */ + end.year = YEAR_MAXIMUM; + } + + /* Add a time change for the start of the period. This may be removed + later if one of the rules expands to exactly the same time. */ + start_index = changes->len; + g_array_append_val (changes, start); + + /* If there are Rules associated with this period, add all the relevant + time changes. */ + save_seconds = 0; + if (zone_line->rules) + found_letter_s = add_rule_changes (zone_line, zone_name, changes, + rule_data, &start, &end, + &start_letter_s, &save_seconds); + else + found_letter_s = FALSE; + + /* FIXME: I'm not really sure what to do about finding a LETTER_S for the + first part of the period (i.e. before the first Rule comes into effect). + Currently we try to use the same LETTER_S as the first Rule of the + period which is in local standard time. */ + if (zone_line->save_seconds) + save_seconds = zone_line->save_seconds; + is_daylight = save_seconds ? TRUE : FALSE; + vzictime_start = &g_array_index (changes, VzicTime, start_index); + walloff = vzictime_start->walloff = stdoff + save_seconds; + + /* TEST: See if the first Rule time is exactly the same as the change from + the Zone line. In which case we can remove the Zone line change. */ + if (changes->len > start_index + 1) { + int prev_stdoff, prev_walloff; + + if (start_index > 0) { + VzicTime *v = &g_array_index (changes, VzicTime, start_index - 1); + prev_stdoff = v->stdoff; + prev_walloff = v->walloff; + } else { + prev_stdoff = 0; + prev_walloff = 0; + } + vzictime_first_rule_change = &g_array_index (changes, VzicTime, + start_index + 1); + if (times_match (vzictime_start, prev_stdoff, prev_walloff, + vzictime_first_rule_change, stdoff, walloff)) { +#if 0 + printf ("Removing zone-line change (using new offsets)\n"); +#endif + g_array_remove_index (changes, start_index); + vzictime_start = NULL; + } else if (times_match (vzictime_start, prev_stdoff, prev_walloff, + vzictime_first_rule_change, prev_stdoff, prev_walloff)) { +#if 0 + printf ("Removing zone-line change (using previous offsets)\n"); +#endif + g_array_remove_index (changes, start_index); + vzictime_start = NULL; + } + } + + + if (vzictime_start) { + vzictime_start->tzname = expand_tzname (zone_name, zone_line->format, + found_letter_s, + start_letter_s, is_daylight); + } + + /* The start of the next Zone line is the end time of this one. */ + start = end; + } + + set_previous_offsets (changes); + + output_zone_components (fp, zone_name, changes); + + if (VzicDumpChanges) + dump_changes (changes_fp, zone_name, changes); + + /* Free all the TZNAME fields. */ + for (i = 0; i < changes->len; i++) { + vzictime = &g_array_index (changes, VzicTime, i); + g_free (vzictime->tzname); + } + + g_array_free (changes, TRUE); +} + + +/* This appends any timezone changes specified by the rules associated with + the timezone, that happen between the start and end times. + It returns the letter_s field of the first STANDARD rule found in the + search. We need this to fill in any %s in the FORMAT field of the first + component of the time period (the Zone line). */ +static gboolean +add_rule_changes (ZoneLineData *zone_line, + char *zone_name, + GArray *changes, + GHashTable *rule_data, + VzicTime *start, + VzicTime *end, + char **start_letter_s, + int *save_seconds) +{ + GArray *rule_array; + RuleData *rule, *prev_rule = NULL; + int stdoff, walloff, i, prev_stdoff, prev_walloff; + VzicTime vzictime; + gboolean is_daylight, found_start_letter_s = FALSE; + gboolean checked_for_previous = FALSE; + + *save_seconds = 0; + + rule_array = g_hash_table_lookup (rule_data, zone_line->rules); + if (!rule_array) { + fprintf (stderr, "Couldn't access rules: %s\n", zone_line->rules); + exit (1); + } + + /* The stdoff is the same for all the rules. */ + stdoff = start->stdoff; + + /* The walloff changes as we go through the rules. */ + walloff = start->walloff; + + /* Get the stdoff & walloff from the last change before this period. */ + if (changes->len >= 2) { + VzicTime *change = &g_array_index (changes, VzicTime, changes->len - 2); + prev_stdoff = change->stdoff; + prev_walloff = change->walloff; + } else { + prev_stdoff = prev_walloff = 0; + } + + + for (i = 0; i < rule_array->len; i++) { + rule = &g_array_index (rule_array, RuleData, i); + + is_daylight = rule->save_seconds != 0 ? TRUE : FALSE; + + vzictime_init (&vzictime); + vzictime.year = rule->from_year; + vzictime.month = rule->in_month; + vzictime.day_code = rule->on_day_code; + vzictime.day_number = rule->on_day_number; + vzictime.day_weekday = rule->on_day_weekday; + vzictime.time_seconds = rule->at_time_seconds; + vzictime.time_code = rule->at_time_code; + vzictime.stdoff = stdoff; + vzictime.walloff = stdoff + rule->save_seconds; + vzictime.is_infinite = (rule->to_year == YEAR_MAXIMUM) ? TRUE : FALSE; + + /* If the rule time is before the given start time, skip it. */ + if (compare_times (&vzictime, stdoff, walloff, + start, prev_stdoff, prev_walloff) < 0) + continue; + + /* If the previous Rule was a daylight Rule, then we may want to use the + walloff from that. */ + if (!checked_for_previous) { + checked_for_previous = TRUE; + if (i > 0) { + prev_rule = &g_array_index (rule_array, RuleData, i - 1); + if (prev_rule->save_seconds) { + walloff = start->walloff = stdoff + prev_rule->save_seconds; + *save_seconds = prev_rule->save_seconds; + found_start_letter_s = TRUE; + *start_letter_s = prev_rule->letter_s; +#if 0 + printf ("Could use save_seconds from previous Rule: %s\n", + zone_name); +#endif + } + } + } + + /* If an end time has been given, then if the rule time is on or after it + break out of the loop. */ + if (end->year != YEAR_MAXIMUM + && compare_times (&vzictime, stdoff, walloff, + end, stdoff, walloff) >= 0) + break; + + vzictime.tzname = expand_tzname (zone_name, zone_line->format, TRUE, + rule->letter_s, is_daylight); + + g_array_append_val (changes, vzictime); + + /* When we find the first STANDARD time we set letter_s. */ + if (!found_start_letter_s && !is_daylight) { + found_start_letter_s = TRUE; + *start_letter_s = rule->letter_s; + } + + /* Now that we have added the Rule, the new walloff comes into effect + for any following Rules. */ + walloff = vzictime.walloff; + } + + return found_start_letter_s; +} + + +/* This expands the Zone line FORMAT field, using the given LETTER_S from a + Rule line. There are 3 types of FORMAT field: + 1. a string with an %s in, e.g. "WE%sT". The %s is replaced with LETTER_S. + 2. a string with an '/' in, e.g. "CAT/CAWT". The first part is used for + standard time and the second part for when daylight-saving is in effect. + 3. a plain string, e.g. "LMT", which we leave as-is. + Note that (1) is the only type in which letter_s is required. +*/ +static char* +expand_tzname (char *zone_name, + char *format, + gboolean have_letter_s, + char *letter_s, + gboolean is_daylight) +{ + char *p, buffer[256], *guess = NULL; + int len; + +#if 0 + printf ("Expanding %s with %s\n", format, letter_s); +#endif + + if (!format || !format[0]) { + fprintf (stderr, "Missing FORMAT\n"); + exit (1); + } + + /* 1. Look for a "%s". */ + p = strchr (format, '%'); + if (p && *(p + 1) == 's') { + if (!have_letter_s) { + + /* NOTE: These are a few hard-coded TZNAMEs that I've looked up myself. + These are needed in a few places where a Zone line comes into effect + but no Rule has been found, so we have no LETTER_S to use. + I've tried to use whatever is the normal LETTER_S in the Rules for + the particular zone, in local standard time. */ + if (!strcmp (zone_name, "Asia/Macao") + && !strcmp (format, "C%sT")) + guess = "CST"; + else if (!strcmp (zone_name, "Asia/Macau") + && !strcmp (format, "C%sT")) + guess = "CST"; + else if (!strcmp (zone_name, "Asia/Ashgabat") + && !strcmp (format, "ASH%sT")) + guess = "ASHT"; + else if (!strcmp (zone_name, "Asia/Ashgabat") + && !strcmp (format, "TM%sT")) + guess = "TMT"; + else if (!strcmp (zone_name, "Asia/Samarkand") + && !strcmp (format, "TAS%sT")) + guess = "TAST"; + else if (!strcmp (zone_name, "Atlantic/Azores") + && !strcmp (format, "WE%sT")) + guess = "WET"; + else if (!strcmp (zone_name, "Europe/Paris") + && !strcmp (format, "WE%sT")) + guess = "WET"; + else if (!strcmp (zone_name, "Europe/Warsaw") + && !strcmp (format, "CE%sT")) + guess = "CET"; + else if (!strcmp (zone_name, "America/Phoenix") + && !strcmp (format, "M%sT")) + guess = "MST"; + else if (!strcmp (zone_name, "America/Nome") + && !strcmp (format, "Y%sT")) + guess = "YST"; + + if (guess) { +#if 0 + fprintf (stderr, + "WARNING: Couldn't find a LETTER_S to use in FORMAT: %s in Zone: %s Guessing: %s\n", + format, zone_name, guess); +#endif + return g_strdup (guess); + } + +#if 1 + fprintf (stderr, + "WARNING: Couldn't find a LETTER_S to use in FORMAT: %s in Zone: %s Leaving TZNAME empty\n", + format, zone_name); +#endif + +#if 0 + /* This is useful to spot exactly which component had a problem. */ + sprintf (buffer, "FIXME: %s", format); + return g_strdup (buffer); +#else + /* We give up and don't output a TZNAME. */ + return NULL; +#endif + } + + sprintf (buffer, format, letter_s ? letter_s : ""); + return g_strdup (buffer); + } + + /* 2. Look for a "/". */ + p = strchr (format, '/'); + if (p) { + if (is_daylight) { + return g_strdup (p + 1); + } else { + len = p - format; + strncpy (buffer, format, len); + buffer[len] = '\0'; + return g_strdup (buffer); + } + } + + /* 3. Just use format as it is. */ + return g_strdup (format); +} + + +/* Compares 2 VzicTimes, returning strcmp()-like values, i.e. 0 if equal, + 1 if the 1st is after the 2nd and -1 if the 1st is before the 2nd. */ +static int +compare_times (VzicTime *time1, + int stdoff1, + int walloff1, + VzicTime *time2, + int stdoff2, + int walloff2) +{ + VzicTime t1, t2; + int result; + + t1 = *time1; + t2 = *time2; + + calculate_actual_time (&t1, TIME_UNIVERSAL, stdoff1, walloff1); + calculate_actual_time (&t2, TIME_UNIVERSAL, stdoff2, walloff2); + + /* Now we can compare the entire time. */ + if (t1.year > t2.year) + result = 1; + else if (t1.year < t2.year) + result = -1; + + else if (t1.month > t2.month) + result = 1; + else if (t1.month < t2.month) + result = -1; + + else if (t1.day_number > t2.day_number) + result = 1; + else if (t1.day_number < t2.day_number) + result = -1; + + else if (t1.time_seconds > t2.time_seconds) + result = 1; + else if (t1.time_seconds < t2.time_seconds) + result = -1; + + else + result = 0; + +#if 0 + printf ("%i/%i/%i %i <=> %i/%i/%i %i -> %i\n", + t1.day_number, t1.month + 1, t1.year, t1.time_seconds, + t2.day_number, t2.month + 1, t2.year, t2.time_seconds, + result); +#endif + + return result; +} + + +/* Returns TRUE if the 2 times are exactly the same. It will calculate the + actual day, but doesn't convert times. */ +static gboolean +times_match (VzicTime *time1, + int stdoff1, + int walloff1, + VzicTime *time2, + int stdoff2, + int walloff2) +{ + VzicTime t1, t2; + + t1 = *time1; + t2 = *time2; + + calculate_actual_time (&t1, TIME_UNIVERSAL, stdoff1, walloff1); + calculate_actual_time (&t2, TIME_UNIVERSAL, stdoff2, walloff2); + + if (t1.year == t2.year + && t1.month == t2.month + && t1.day_number == t2.day_number + && t1.time_seconds == t2.time_seconds) + return TRUE; + + return FALSE; +} + + +static void +output_zone_components (FILE *fp, + char *name, + GArray *changes) +{ + VzicTime *vzictime; + int i, start_index = 0; + gboolean only_one_change = FALSE; + char start_buffer[1024]; + + fprintf (fp, "BEGIN:VTIMEZONE\nTZID:%s%s\n", TZIDPrefixExpanded, name); + + if (VzicUrlPrefix != NULL) + fprintf (fp, "TZURL:%s/%s\n", VzicUrlPrefix, name); + + /* We use an 'X-' property to place the city name in. */ + fprintf (fp, "X-LIC-LOCATION:%s\n", name); + + /* We try to find any recurring components first, or they may get output + as lots of RDATES instead. */ + if (!VzicNoRRules) { + int num_rrules_output = 0; + + for (i = 1; i < changes->len; i++) { + if (check_for_recurrence (fp, changes, i)) { + num_rrules_output++; + } + } + +#if 0 + printf ("Zone: %s had %i infinite RRULEs\n", CurrentZoneName, + num_rrules_output); +#endif + + if (!VzicPureOutput && num_rrules_output == 2) { +#if 0 + printf ("Zone: %s using 2 RRULEs\n", CurrentZoneName); +#endif + fprintf (fp, "END:VTIMEZONE\n"); + return; + } + } + + /* We skip the first change, which starts at -infinity, unless it is the only + change for the timezone. */ + if (changes->len > 1) + start_index = 1; + else + only_one_change = TRUE; + + /* For pure output, we start at the start of the array and step through it + outputting RDATEs. For Outlook-compatible output we start at the end + and step backwards to find the first STANDARD time to output. */ + if (VzicPureOutput) + i = start_index - 1; + else + i = changes->len; + + for (;;) { + if (VzicPureOutput) + i++; + else + i--; + + if (VzicPureOutput) { + if (i >= changes->len) + break; + } else { + if (i < start_index) + break; + } + + vzictime = &g_array_index (changes, VzicTime, i); + + /* If we have already output this component as part of an RRULE or RDATE, + then we skip it. */ + if (vzictime->output) + continue; + + /* For Outlook-compatible output we only want to output the last STANDARD + time as a DTSTART, so skip any DAYLIGHT changes. */ + if (!VzicPureOutput && vzictime->stdoff != vzictime->walloff) { + printf ("Skipping DAYLIGHT change\n"); + continue; + } + +#if 0 + printf ("Zone: %s using DTSTART Year: %i\n", CurrentZoneName, + vzictime->year); +#endif + + if (VzicPureOutput) { + output_component_start (start_buffer, vzictime, TRUE, only_one_change); + } else { + /* For Outlook compatability we don't output the RDATE and use the same + TZOFFSET for TZOFFSETFROM and TZOFFSETTO. */ + vzictime->year = RDATE_YEAR; + vzictime->month = 0; + vzictime->day_code = DAY_SIMPLE; + vzictime->day_number = 1; + vzictime->time_code = TIME_WALL; + vzictime->time_seconds = 0; + + output_component_start (start_buffer, vzictime, FALSE, TRUE); + } + + fprintf (fp, "%s", start_buffer); + + /* This will look for matching components and output them as RDATEs + instead of separate components. */ + if (VzicPureOutput && !VzicNoRDates) + check_for_rdates (fp, changes, i); + + output_component_end (fp, vzictime); + + vzictime->output = TRUE; + + if (!VzicPureOutput) + break; + } + + fprintf (fp, "END:VTIMEZONE\n"); +} + + +/* This sets the prev_stdoff and prev_walloff (i.e. the TZOFFSETFROM) of each + VzicTime, using the stdoff and walloff of the previous VzicTime. It makes + the rest of the code much simpler. */ +static void +set_previous_offsets (GArray *changes) +{ + VzicTime *vzictime, *prev_vzictime; + int i; + + prev_vzictime = &g_array_index (changes, VzicTime, 0); + prev_vzictime->prev_stdoff = 0; + prev_vzictime->prev_walloff = 0; + + for (i = 1; i < changes->len; i++) { + vzictime = &g_array_index (changes, VzicTime, i); + + vzictime->prev_stdoff = prev_vzictime->stdoff; + vzictime->prev_walloff = prev_vzictime->walloff; + + prev_vzictime = vzictime; + } +} + + +/* Returns TRUE if we output an infinite recurrence. */ +static gboolean +check_for_recurrence (FILE *fp, + GArray *changes, + int idx) +{ + VzicTime *vzictime_start, *vzictime, vzictime_start_copy; + gboolean is_daylight_start, is_daylight; + int last_match, i, next_year, day_offset; + char until[256], rrule_buffer[2048], start_buffer[1024]; + GList *matching_elements = NULL, *elem; + + vzictime_start = &g_array_index (changes, VzicTime, idx); + + /* If this change has already been output, skip it. */ + if (vzictime_start->output) + return FALSE; + + /* There can't possibly be an RRULE starting from YEAR_MINIMUM. */ + if (vzictime_start->year == YEAR_MINIMUM) + return FALSE; + + is_daylight_start = (vzictime_start->stdoff != vzictime_start->walloff) + ? TRUE : FALSE; + +#if 0 + printf ("\nChecking: %s OFFSETFROM: %i %s\n", + format_vzictime (vzictime_start), vzictime_start->prev_walloff, + is_daylight_start ? "DAYLIGHT" : ""); +#endif + + /* If this is an infinitely recurring change, output the RRULE and return. + There won't be any changes after it that we could merge. */ + if (vzictime_start->is_infinite) { + + /* Change the year to our minimum start year. */ + vzictime_start_copy = *vzictime_start; + if (!VzicPureOutput) + vzictime_start_copy.year = RRULE_START_YEAR; + + day_offset = output_component_start (start_buffer, &vzictime_start_copy, + FALSE, FALSE); + + if (!output_rrule (rrule_buffer, vzictime_start_copy.month, + vzictime_start_copy.day_code, + vzictime_start_copy.day_number, + vzictime_start_copy.day_weekday, day_offset, "")) { + if (vzictime_start->year != MAX_TIME_T_YEAR) { + fprintf (stderr, "WARNING: Failed to output infinite recurrence with start year: %i\n", vzictime_start->year); + } + return TRUE; + } + + fprintf (fp, "%s%s", start_buffer, rrule_buffer); + output_component_end (fp, vzictime_start); + vzictime_start->output = TRUE; + return TRUE; + } + + last_match = idx; + next_year = vzictime_start->year + 1; + for (i = idx + 1; i < changes->len; i++) { + vzictime = &g_array_index (changes, VzicTime, i); + + is_daylight = (vzictime->stdoff != vzictime->walloff) ? TRUE : FALSE; + + if (vzictime->output) + continue; + +#if 0 + printf (" %s OFFSETFROM: %i %s\n", + format_vzictime (vzictime), vzictime->prev_walloff, + is_daylight ? "DAYLIGHT" : ""); +#endif + + /* If it is more than one year ahead, we are finished, since we want + consecutive years. */ + if (vzictime->year > next_year) { + break; + } + + /* It must be the same type of component - STANDARD or DAYLIGHT. */ + if (is_daylight != is_daylight_start) { + continue; + } + + /* It must be the following year, with the same month, day & time. + It is possible that the time has a different code but does in fact + match when normalized, but we don't care (for now at least). */ + if (vzictime->year != next_year + || vzictime->month != vzictime_start->month + || vzictime->day_code != vzictime_start->day_code + || vzictime->day_number != vzictime_start->day_number + || vzictime->day_weekday != vzictime_start->day_weekday + || vzictime->time_seconds != vzictime_start->time_seconds + || vzictime->time_code != vzictime_start->time_code) { + continue; + } + + /* The TZOFFSETFROM and TZOFFSETTO must match. */ + if (vzictime->prev_walloff != vzictime_start->prev_walloff) { + continue; + } + + if (vzictime->walloff != vzictime_start->walloff) { + continue; + } + + /* TZNAME must match. */ + if (!timezones_match (vzictime->tzname, vzictime_start->tzname)) { + continue; + } + + /* We have a match. */ + last_match = i; + next_year = vzictime->year + 1; + + matching_elements = g_list_prepend (matching_elements, vzictime); + } + + if (last_match == idx) + return FALSE; + +#if 0 + printf ("Found recurrence %i - %i!!!\n", vzictime_start->year, + next_year - 1); +#endif + + vzictime = &g_array_index (changes, VzicTime, last_match); + +/* We only use RRULEs if there are at least MIN_RRULE_OCCURRENCES occurrences, + since otherwise RDATEs are more efficient. */ + if (!vzictime->is_infinite) { + int years = vzictime->year - vzictime_start->year + 1; +#if 0 + printf ("RRULE Years: %i\n", years); +#endif + if (years < MIN_RRULE_OCCURRENCES) + return FALSE; + } + + if (vzictime->is_infinite) { + until[0] = '\0'; + } else { + VzicTime t1 = *vzictime; + + printf ("RRULE with UNTIL - aborting\n"); + abort (); + + calculate_actual_time (&t1, TIME_UNIVERSAL, vzictime->prev_stdoff, + vzictime->prev_walloff); + + /* Output UNTIL, in UTC. */ + sprintf (until, ";UNTIL=%sZ", format_time (t1.year, t1.month, + t1.day_number, + t1.time_seconds)); + } + + /* Change the year to our minimum start year. */ + vzictime_start_copy = *vzictime_start; + if (!VzicPureOutput) + vzictime_start_copy.year = RRULE_START_YEAR; + + day_offset = output_component_start (start_buffer, &vzictime_start_copy, + FALSE, FALSE); + if (output_rrule (rrule_buffer, vzictime_start_copy.month, + vzictime_start_copy.day_code, + vzictime_start_copy.day_number, + vzictime_start_copy.day_weekday, day_offset, until)) { + fprintf (fp, "%s%s", start_buffer, rrule_buffer); + output_component_end (fp, vzictime_start); + + /* Mark all the changes as output. */ + vzictime_start->output = TRUE; + for (elem = matching_elements; elem; elem = elem->next) { + vzictime = elem->data; + vzictime->output = TRUE; + } + } + + g_list_free (matching_elements); + + return TRUE; +} + + +static void +check_for_rdates (FILE *fp, + GArray *changes, + int idx) +{ + VzicTime *vzictime_start, *vzictime, tmp_vzictime; + gboolean is_daylight_start, is_daylight; + int i, year, month, day, time; + + vzictime_start = &g_array_index (changes, VzicTime, idx); + + is_daylight_start = (vzictime_start->stdoff != vzictime_start->walloff) + ? TRUE : FALSE; + +#if 0 + printf ("\nChecking: %s OFFSETFROM: %i %s\n", + format_vzictime (vzictime_start), vzictime_start->prev_walloff, + is_daylight_start ? "DAYLIGHT" : ""); +#endif + + /* We want to go backwards through the array now, for Outlook compatability. + (It only looks at the first DTSTART/RDATE.) */ + for (i = idx + 1; i < changes->len; i++) { + vzictime = &g_array_index (changes, VzicTime, i); + + is_daylight = (vzictime->stdoff != vzictime->walloff) ? TRUE : FALSE; + + if (vzictime->output) + continue; + +#if 0 + printf (" %s OFFSETFROM: %i %s\n", format_vzictime (vzictime), + vzictime->prev_walloff, is_daylight ? "DAYLIGHT" : ""); +#endif + + /* It must be the same type of component - STANDARD or DAYLIGHT. */ + if (is_daylight != is_daylight_start) { + continue; + } + + /* The TZOFFSETFROM and TZOFFSETTO must match. */ + if (vzictime->prev_walloff != vzictime_start->prev_walloff) { + continue; + } + + if (vzictime->walloff != vzictime_start->walloff) { + continue; + } + + /* TZNAME must match. */ + if (!timezones_match (vzictime->tzname, vzictime_start->tzname)) { + continue; + } + + /* We have a match. */ + + tmp_vzictime = *vzictime; + calculate_actual_time (&tmp_vzictime, TIME_WALL, vzictime->prev_stdoff, + vzictime->prev_walloff); + + fprintf (fp, "RDATE:%s\n", format_time (tmp_vzictime.year, + tmp_vzictime.month, + tmp_vzictime.day_number, + tmp_vzictime.time_seconds)); + + vzictime->output = TRUE; + } +} + + +static gboolean +timezones_match (char *tzname1, + char *tzname2) +{ + if (tzname1 && tzname2 && !strcmp (tzname1, tzname2)) + return TRUE; + + if (!tzname1 && !tzname2) + return TRUE; + + return FALSE; +} + + +/* Outputs the start of a VTIMEZONE component, with the BEGIN line, + the DTSTART, TZOFFSETFROM, TZOFFSETTO & TZNAME properties. */ +static int +output_component_start (char *buffer, + VzicTime *vzictime, + gboolean output_rdate, + gboolean use_same_tz_offset) +{ + gboolean is_daylight, skip_day_offset = FALSE; + gint year, month, day, time, day_offset = 0; + GDate old_date, new_date; + char *formatted_time; + char line1[1024], line2[1024], line3[1024]; + char line4[1024], line5[1024], line6[1024]; + VzicTime tmp_vzictime; + int prev_walloff; + + is_daylight = (vzictime->stdoff != vzictime->walloff) ? TRUE : FALSE; + + tmp_vzictime = *vzictime; + day_offset = calculate_actual_time (&tmp_vzictime, TIME_WALL, + vzictime->prev_stdoff, + vzictime->prev_walloff); + + sprintf (line1, "BEGIN:%s\n", is_daylight ? "DAYLIGHT" : "STANDARD"); + + /* If the timezone only has one change, that means it uses the same offset + forever, so we use the same TZOFFSETFROM as the TZOFFSETTO. (If the zone + has more than one change, we don't output the first one.) */ + if (use_same_tz_offset) + prev_walloff = vzictime->walloff; + else + prev_walloff = vzictime->prev_walloff; + + sprintf (line2, "TZOFFSETFROM:%s\n", + format_tz_offset (prev_walloff, !VzicPureOutput)); + + sprintf (line3, "TZOFFSETTO:%s\n", + format_tz_offset (vzictime->walloff, !VzicPureOutput)); + + if (vzictime->tzname) + sprintf (line4, "TZNAME:%s\n", vzictime->tzname); + else + line4[0] = '\0'; + + formatted_time = format_time (tmp_vzictime.year, tmp_vzictime.month, + tmp_vzictime.day_number, + tmp_vzictime.time_seconds); + sprintf (line5, "DTSTART:%s\n", formatted_time); + if (output_rdate) + sprintf (line6, "RDATE:%s\n", formatted_time); + else + line6[0] = '\0'; + + sprintf (buffer, "%s%s%s%s%s%s", line1, line2, line3, line4, line5, line6); + + return day_offset; +} + + +/* Outputs the END line of the VTIMEZONE component. */ +static void +output_component_end (FILE *fp, + VzicTime *vzictime) +{ + gboolean is_daylight; + + is_daylight = (vzictime->stdoff != vzictime->walloff) ? TRUE : FALSE; + + fprintf (fp, "END:%s\n", is_daylight ? "DAYLIGHT" : "STANDARD"); +} + + +/* Initializes a VzicTime to 1st Jan in YEAR_MINIMUM at midnight, with all + offsets set to 0. */ +static void +vzictime_init (VzicTime *vzictime) +{ + vzictime->year = YEAR_MINIMUM; + vzictime->month = 0; + vzictime->day_code = DAY_SIMPLE; + vzictime->day_number = 1; + vzictime->day_weekday = 0; + vzictime->time_seconds = 0; + vzictime->time_code = TIME_UNIVERSAL; + vzictime->stdoff = 0; + vzictime->walloff = 0; + vzictime->is_infinite = FALSE; + vzictime->output = FALSE; + vzictime->prev_stdoff = 0; + vzictime->prev_walloff = 0; + vzictime->tzname = NULL; +} + + +/* This calculates the actual local time that a change will occur, given + the offsets from standard and wall-clock time. It returns -1 or 1 if it + had to move backwards or forwards one day while converting to local time. + If it does this then we need to change the RRULEs we output. */ +static int +calculate_actual_time (VzicTime *vzictime, + TimeCode time_code, + int stdoff, + int walloff) +{ + GDate date; + gint day_offset, days_in_month, weekday, offset, result; + + vzictime->time_seconds = calculate_wall_time (vzictime->time_seconds, + vzictime->time_code, + stdoff, walloff, &day_offset); + + if (vzictime->day_code != DAY_SIMPLE) { + if (vzictime->year == YEAR_MINIMUM || vzictime->year == YEAR_MAXIMUM) { + fprintf (stderr, "In calculate_actual_time: invalid year\n"); + exit (0); + } + + g_date_clear (&date, 1); + days_in_month = g_date_days_in_month (vzictime->month + 1, vzictime->year); + + /* Note that the day_code refers to the date before we convert it to + a wall-clock date and time. So we find the day it was referring to, + then make any adjustments needed due to converting the time. */ + if (vzictime->day_code == DAY_LAST_WEEKDAY) { + /* Find out what day the last day of the month is. */ + g_date_set_dmy (&date, days_in_month, vzictime->month + 1, + vzictime->year); + weekday = g_date_weekday (&date) % 7; + + /* Calculate how many days we have to go back to get to day_weekday. */ + offset = (weekday + 7 - vzictime->day_weekday) % 7; + + vzictime->day_number = days_in_month - offset; + } else { + /* Find out what day day_number actually is. */ + g_date_set_dmy (&date, vzictime->day_number, vzictime->month + 1, + vzictime->year); + weekday = g_date_weekday (&date) % 7; + + if (vzictime->day_code == DAY_WEEKDAY_ON_OR_AFTER) + offset = (vzictime->day_weekday + 7 - weekday) % 7; + else + offset = - ((weekday + 7 - vzictime->day_weekday) % 7); + + vzictime->day_number = vzictime->day_number + offset; + } + + vzictime->day_code = DAY_SIMPLE; + + if (vzictime->day_number <= 0 || vzictime->day_number > days_in_month) { + fprintf (stderr, "Day overflow: %i\n", vzictime->day_number); + exit (1); + } + } + +#if 0 + fprintf (stderr, "%s -> %i/%i/%i\n", + dump_day_coded (vzictime->day_code, vzictime->day_number, + vzictime->day_weekday), + vzictime->day_number, vzictime->month + 1, vzictime->year); +#endif + + fix_time_overflow (&vzictime->year, &vzictime->month, + &vzictime->day_number, day_offset); + + /* If we want UTC time, we have to convert it now. */ + if (time_code == TIME_UNIVERSAL) { + vzictime->time_seconds = calculate_until_time (vzictime->time_seconds, + TIME_WALL, stdoff, walloff, + &vzictime->year, + &vzictime->month, + &vzictime->day_number); + } + + return day_offset; +} + + +/* This converts the given time into universal time (UTC), to be used in + the UNTIL property. */ +static int +calculate_until_time (int time, + TimeCode time_code, + int stdoff, + int walloff, + int *year, + int *month, + int *day) +{ + int result, day_offset; + + day_offset = 0; + + switch (time_code) { + case TIME_WALL: + result = time - walloff; + break; + case TIME_STANDARD: + result = time - stdoff; + break; + case TIME_UNIVERSAL: + return time; + default: + fprintf (stderr, "Invalid time code\n"); + exit (1); + } + + if (result < 0) { + result += 24 * 60 * 60; + day_offset = -1; + } else if (result >= 24 * 60 * 60) { + result -= 24 * 60 * 60; + day_offset = 1; + } + + /* Sanity check - we shouldn't have an overflow any more. */ + if (result < 0 || result >= 24 * 60 * 60) { + fprintf (stderr, "Time overflow: %i\n", result); + abort (); + } + + fix_time_overflow (year, month, day, day_offset); + + return result; +} + + +/* This converts the given time into wall clock time (the local standard time + with any adjustment for daylight-saving). */ +static int +calculate_wall_time (int time, + TimeCode time_code, + int stdoff, + int walloff, + int *day_offset) +{ + int result; + + *day_offset = 0; + + switch (time_code) { + case TIME_WALL: + return time; + case TIME_STANDARD: + /* We have a local standard time, so we have to subtract stdoff to get + back to UTC, then add walloff to get wall time. */ + result = time - stdoff + walloff; + break; + case TIME_UNIVERSAL: + result = time + walloff; + break; + default: + fprintf (stderr, "Invalid time code\n"); + exit (1); + } + + if (result < 0) { + result += 24 * 60 * 60; + *day_offset = -1; + } else if (result >= 24 * 60 * 60) { + result -= 24 * 60 * 60; + *day_offset = 1; + } + + /* Sanity check - we shouldn't have an overflow any more. */ + if (result < 0 || result >= 24 * 60 * 60) { + fprintf (stderr, "Time overflow: %i\n", result); + exit (1); + } + +#if 0 + printf ("%s -> ", dump_time (time, time_code, TRUE)); + printf ("%s (%i)\n", dump_time (result, TIME_WALL, TRUE), *day_offset); +#endif + + return result; +} + + +static void +fix_time_overflow (int *year, + int *month, + int *day, + int day_offset) +{ + if (day_offset == -1) { + *day = *day - 1; + + if (*day == 0) { + *month = *month - 1; + if (*month == -1) { + *month = 11; + *year = *year - 1; + } + *day = g_date_days_in_month (*month + 1, *year); + } + } else if (day_offset == 1) { + *day = *day + 1; + + if (*day > g_date_days_in_month (*month + 1, *year)) { + *month = *month + 1; + if (*month == 12) { + *month = 0; + *year = *year + 1; + } + *day = 1; + } + } +} + + +static char* +format_time (int year, + int month, + int day, + int time) +{ + static char buffer[128]; + int hour, minute, second; + + /* When we are outputting the first component year will be YEAR_MINIMUM. + We used to use 1 when outputting this, but Outlook doesn't like any years + less that 1600, so we use 1600 instead. We don't output the first change + for most zones now, so it doesn't matter too much. */ + if (year == YEAR_MINIMUM) + year = 1601; + + /* We just use 9999 here, so we keep to 4 characters. But this should only + be needed when debugging - it shouldn't be needed in the VTIMEZONEs. */ + if (year == YEAR_MAXIMUM) { + fprintf (stderr, "format_time: YEAR_MAXIMUM used\n"); + year = 9999; + } + + hour = time / 3600; + minute = (time % 3600) / 60; + second = time % 60; + + sprintf (buffer, "%04i%02i%02iT%02i%02i%02i", + year, month + 1, day, hour, minute, second); + + return buffer; +} + + +/* Outlook doesn't support 6-digit values, i.e. including the seconds, so + we round to the nearest minute. No current offsets use the seconds value, + so we aren't losing much. */ +static char* +format_tz_offset (int tz_offset, + gboolean round_seconds) +{ + static char buffer[128]; + char *sign = "+"; + int hours, minutes, seconds; + + if (tz_offset < 0) { + tz_offset = -tz_offset; + sign = "-"; + } + + if (round_seconds) + tz_offset += 30; + + hours = tz_offset / 3600; + minutes = (tz_offset % 3600) / 60; + seconds = tz_offset % 60; + + if (round_seconds) + seconds = 0; + + /* Sanity check. Standard timezone offsets shouldn't be much more than 12 + hours, and daylight saving shouldn't change it by more than a few hours. + (The maximum offset is 15 hours 56 minutes at present.) */ + if (hours < 0 || hours >= 24 || minutes < 0 || minutes >= 60 + || seconds < 0 || seconds >= 60) { + fprintf (stderr, "WARNING: Strange timezone offset: H:%i M:%i S:%i\n", + hours, minutes, seconds); + } + + if (seconds == 0) + sprintf (buffer, "%s%02i%02i", sign, hours, minutes); + else + sprintf (buffer, "%s%02i%02i%02i", sign, hours, minutes, seconds); + + return buffer; +} + + +static gboolean +output_rrule (char *rrule_buffer, + int month, + DayCode day_code, + int day_number, + int day_weekday, + int day_offset, + char *until) +{ + char buffer[1024], buffer2[1024]; + + buffer[0] = '\0'; + + if (day_offset > 1 || day_offset < -1) { + fprintf (stderr, "Invalid day_offset: %i\n", day_offset); + exit (0); + } + + /* If the DTSTART time was moved to another day when converting to local + time, we need to adjust the RRULE accordingly. e.g. If the original RRULE + was on the 19th of the month, but DTSTART was moved 1 day forward, then + we output the 20th of the month instead. */ + if (day_offset == 1) { + if (day_code != DAY_LAST_WEEKDAY) + day_number++; + day_weekday = (day_weekday + 1) % 7; + + /* Check we don't use February 29th. */ + if (month == 1 && day_number > 28) { + fprintf (stderr, "Can't format RRULE - out of bounds. Month: %i Day number: %i\n", month + 1, day_number); + exit (0); + } + + /* If we go past the end of the month, move to the next month. */ + if (day_code != DAY_LAST_WEEKDAY && day_number > DaysInMonth[month]) { + month++; + day_number = 1; + } + + } else if (day_offset == -1) { + if (day_code != DAY_LAST_WEEKDAY) + day_number--; + day_weekday = (day_weekday + 6) % 7; + + if (day_code != DAY_LAST_WEEKDAY && day_number < 1) + fprintf (stderr, "Month: %i Day number: %i\n", month + 1, day_number); + } + + switch (day_code) { + case DAY_SIMPLE: + /* Outlook (2000) will not parse the simple YEARLY RRULEs in VTIMEZONEs, + or BYMONTHDAY, or BYYEARDAY, which makes this option difficult! + Currently we use something like BYDAY=1SU, which will be incorrect + at times. This only affects Asia/Baghdad, Asia/Gaza, Asia/Jerusalem & + Asia/Damascus at present (and Jerusalem doesn't have specific rules + at the moment anyway, so that isn't a big loss). */ + if (!VzicPureOutput) { + if (day_number < 8) { + printf ("WARNING: %s: Outputting BYDAY=1SU instead of BYMONTHDAY=1-7 for Outlook compatability\n", CurrentZoneName); + sprintf (buffer, "RRULE:FREQ=YEARLY;BYMONTH=%i;BYDAY=1SU", + month + 1); + } else if (day_number < 15) { + printf ("WARNING: %s: Outputting BYDAY=2SU instead of BYMONTHDAY=8-14 for Outlook compatability\n", CurrentZoneName); + sprintf (buffer, "RRULE:FREQ=YEARLY;BYMONTH=%i;BYDAY=2SU", + month + 1); + } else if (day_number < 22) { + printf ("WARNING: %s: Outputting BYDAY=3SU instead of BYMONTHDAY=15-21 for Outlook compatability\n", CurrentZoneName); + sprintf (buffer, "RRULE:FREQ=YEARLY;BYMONTH=%i;BYDAY=3SU", + month + 1); + } else { + printf ("ERROR: %s: Couldn't output RRULE (day=%i) compatible with Outlook\n", CurrentZoneName, day_number); + exit (1); + } + } else { + sprintf (buffer, "RRULE:FREQ=YEARLY"); + } + break; + + case DAY_WEEKDAY_ON_OR_AFTER: + if (day_number > DaysInMonth[month] - 6) { + /* This isn't actually needed at present. */ +#if 0 + fprintf (stderr, "DAY_WEEKDAY_ON_OR_AFTER: %i %i\n", day_number, + month + 1); +#endif + + if (!VzicPureOutput) { + printf ("ERROR: %s: Couldn't output RRULE (day>=x) compatible with Outlook\n", CurrentZoneName); + exit (1); + } else { + /* We do 6 days at the end of this month, and 1 at the start of the + next. We can't do this if we want Outlook compatability, as it + needs BYMONTHDAY, which Outlook doesn't support. */ + sprintf (buffer, + "RRULE:FREQ=YEARLY;BYMONTH=%i;BYMONTHDAY=%i,%i,%i,%i,%i,%i;BYDAY=%s", + month + 1, + day_number, day_number + 1, day_number + 2, day_number + 3, + day_number + 4, day_number + 5, + WeekDays[day_weekday]); + + sprintf (buffer2, + "RRULE:FREQ=YEARLY;BYMONTH=%i;BYMONTHDAY=1;BYDAY=%s", + (month + 1) % 12 + 1, + WeekDays[day_weekday]); + + sprintf (rrule_buffer, "%s%s\n%s%s\n", + buffer, until, buffer2, until); + + return TRUE; + } + } + + if (!output_rrule_2 (buffer, month, day_number, day_weekday)) + return FALSE; + + break; + + case DAY_WEEKDAY_ON_OR_BEFORE: + if (day_number < 7) { + /* FIXME: This is unimplemented, but it isn't needed at present anway. */ + fprintf (stderr, "DAY_WEEKDAY_ON_OR_BEFORE: %i. Unimplemented. Exiting...\n", day_number); + exit (0); + } + + if (!output_rrule_2 (buffer, month, day_number - 6, day_weekday)) + return FALSE; + + break; + + case DAY_LAST_WEEKDAY: + if (day_offset == 1) { + if (month == 1) { + fprintf (stderr, "DAY_LAST_WEEKDAY - day moved, in February - can't fix\n"); + exit (0); + } + + /* This is only used once at present, for Africa/Cairo. */ +#if 0 + fprintf (stderr, "DAY_LAST_WEEKDAY - day moved\n"); +#endif + + if (!VzicPureOutput) { + printf ("WARNING: %s: Modifying RRULE (last weekday) for Outlook compatability\n", CurrentZoneName); + sprintf (buffer, + "RRULE:FREQ=YEARLY;BYMONTH=%i;BYDAY=-1%s", + month + 1, WeekDays[day_weekday]); + printf (" Outputting: %s\n", buffer); + } else { + /* We do 6 days at the end of this month, and 1 at the start of the + next. We can't do this if we want Outlook compatability, as it needs + BYMONTHDAY, which Outlook doesn't support. */ + day_number = DaysInMonth[month]; + sprintf (buffer, + "RRULE:FREQ=YEARLY;BYMONTH=%i;BYMONTHDAY=%i,%i,%i,%i,%i,%i;BYDAY=%s", + month + 1, + day_number - 5, day_number - 4, day_number - 3, + day_number - 2, day_number - 1, day_number, + WeekDays[day_weekday]); + + sprintf (buffer2, + "RRULE:FREQ=YEARLY;BYMONTH=%i;BYMONTHDAY=1;BYDAY=%s", + (month + 1) % 12 + 1, + WeekDays[day_weekday]); + + sprintf (rrule_buffer, "%s%s\n%s%s\n", + buffer, until, buffer2, until); + + return TRUE; + } + + } else if (day_offset == -1) { + /* We do 7 days 1 day before the end of this month. */ + day_number = DaysInMonth[month]; + + if (!output_rrule_2 (buffer, month, day_number - 7, day_weekday)) + return FALSE; + + sprintf (rrule_buffer, "%s%s\n", buffer, until); + return TRUE; + } + + sprintf (buffer, + "RRULE:FREQ=YEARLY;BYMONTH=%i;BYDAY=-1%s", + month + 1, WeekDays[day_weekday]); + break; + + default: + fprintf (stderr, "Invalid day code\n"); + exit (1); + } + + sprintf (rrule_buffer, "%s%s\n", buffer, until); + return TRUE; +} + + +/* This tries to convert a RRULE like 'BYMONTHDAY=8,9,10,11,12,13,14;BYDAY=FR' + into 'BYDAY=2FR'. We need this since Outlook doesn't accept BYMONTHDAY. + It returns FALSE if conversion is not possible. */ +static gboolean +output_rrule_2 (char *buffer, + int month, + int day_number, + int day_weekday) +{ + + if (day_number == 1) { + /* Convert it to a BYDAY=1SU type of RRULE. */ + sprintf (buffer, "RRULE:FREQ=YEARLY;BYMONTH=%i;BYDAY=1%s", + month + 1, WeekDays[day_weekday]); + + } else if (day_number == 8) { + /* Convert it to a BYDAY=2SU type of RRULE. */ + sprintf (buffer, "RRULE:FREQ=YEARLY;BYMONTH=%i;BYDAY=2%s", + month + 1, WeekDays[day_weekday]); + + } else if (day_number == 15) { + /* Convert it to a BYDAY=3SU type of RRULE. */ + sprintf (buffer, "RRULE:FREQ=YEARLY;BYMONTH=%i;BYDAY=3%s", + month + 1, WeekDays[day_weekday]); + + } else if (day_number == 22) { + /* Convert it to a BYDAY=4SU type of RRULE. (Currently not used.) */ + sprintf (buffer, "RRULE:FREQ=YEARLY;BYMONTH=%i;BYDAY=4%s", + month + 1, WeekDays[day_weekday]); + + } else if (month != 1 && day_number == DaysInMonth[month] - 6) { + /* Convert it to a BYDAY=-1SU type of RRULE. (But never for February.) */ + sprintf (buffer, "RRULE:FREQ=YEARLY;BYMONTH=%i;BYDAY=-1%s", + month + 1, WeekDays[day_weekday]); + + } else { + /* Can't convert to a correct RRULE. If we want Outlook compatability we + have to use a slightly incorrect RRULE, so the time change will be 1 + week out every 7 or so years. Alternatively we could possibly move the + change by an hour or so so we would always be 1 or 2 hours out, but + never 1 week out. Yes, that sounds a better idea. */ + if (!VzicPureOutput) { + printf ("WARNING: %s: Modifying RRULE to be compatible with Outlook (day >= %i, month = %i)\n", CurrentZoneName, day_number, month + 1); + + if (day_number == 2) { + /* Convert it to a BYDAY=1SU type of RRULE. + This is needed for Asia/Karachi. */ + sprintf (buffer, "RRULE:FREQ=YEARLY;BYMONTH=%i;BYDAY=1%s", + month + 1, WeekDays[day_weekday]); + } else if (day_number == 9) { + /* Convert it to a BYDAY=2SU type of RRULE. + This is needed for Antarctica/Palmer & America/Santiago. */ + sprintf (buffer, "RRULE:FREQ=YEARLY;BYMONTH=%i;BYDAY=2%s", + month + 1, WeekDays[day_weekday]); + } else if (month != 1 && day_number == DaysInMonth[month] - 7) { + /* Convert it to a BYDAY=-1SU type of RRULE. (But never for February.) + This is needed for America/Godthab. */ + sprintf (buffer, "RRULE:FREQ=YEARLY;BYMONTH=%i;BYDAY=-1%s", + month + 1, WeekDays[day_weekday]); + } else { + printf ("ERROR: %s: Couldn't modify RRULE to be compatible with Outlook (day >= %i, month = %i)\n", CurrentZoneName, day_number, month + 1); + exit (1); + } + + } else { + sprintf (buffer, + "RRULE:FREQ=YEARLY;BYMONTH=%i;BYMONTHDAY=%i,%i,%i,%i,%i,%i,%i;BYDAY=%s", + month + 1, + day_number, day_number + 1, day_number + 2, day_number + 3, + day_number + 4, day_number + 5, day_number + 6, + WeekDays[day_weekday]); + } + } + + return TRUE; +} + + +static char* +format_vzictime (VzicTime *vzictime) +{ + static char buffer[1024]; + + sprintf (buffer, "%s %2i %s %s %i %i %s", + dump_year (vzictime->year), vzictime->month + 1, + dump_day_coded (vzictime->day_code, vzictime->day_number, + vzictime->day_weekday), + dump_time (vzictime->time_seconds, vzictime->time_code, TRUE), + vzictime->stdoff, vzictime->walloff, + vzictime->is_infinite ? "INFINITE" : ""); + + return buffer; +} + + +static void +dump_changes (FILE *fp, + char *zone_name, + GArray *changes) +{ + VzicTime *vzictime, *vzictime2 = NULL; + int i, year_offset, year; + + for (i = 0; i < changes->len; i++) { + vzictime = &g_array_index (changes, VzicTime, i); + + if (vzictime->year > MAX_CHANGES_YEAR) + return; + + dump_change (fp, zone_name, vzictime, vzictime->year); + } + + if (changes->len < 2) + return; + + /* Now see if the changes array ends with a pair of recurring changes. */ + vzictime = &g_array_index (changes, VzicTime, changes->len - 2); + vzictime2 = &g_array_index (changes, VzicTime, changes->len - 1); + if (!vzictime->is_infinite || !vzictime2->is_infinite) + return; + + year_offset = 1; + for (;;) { + year = vzictime->year + year_offset; + if (year > MAX_CHANGES_YEAR) + break; + dump_change (fp, zone_name, vzictime, year); + + year = vzictime2->year + year_offset; + if (year > MAX_CHANGES_YEAR) + break; + dump_change (fp, zone_name, vzictime2, year); + + year_offset++; + } +} + + +static void +dump_change (FILE *fp, + char *zone_name, + VzicTime *vzictime, + int year) +{ + int hour, minute, second; + VzicTime tmp_vzictime; + static char *months[] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun", + "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" }; + + /* Output format is: + + Zone-Name [tab] Date [tab] Time [tab] UTC-Offset + + The Date and Time fields specify the time change in UTC. + + The UTC Offset is for local (wall-clock) time. It is the amount of time + to add to UTC to get local time. + */ + + fprintf (fp, "%s\t", zone_name); + + if (year == YEAR_MINIMUM) { + fprintf (fp, " 1 Jan 0001\t 0:00:00", zone_name); + } else if (year == YEAR_MAXIMUM) { + fprintf (stderr, "Maximum year found in change time\n"); + exit (1); + } else { + tmp_vzictime = *vzictime; + tmp_vzictime.year = year; + calculate_actual_time (&tmp_vzictime, TIME_UNIVERSAL, + vzictime->prev_stdoff, vzictime->prev_walloff); + + hour = tmp_vzictime.time_seconds / 3600; + minute = (tmp_vzictime.time_seconds % 3600) / 60; + second = tmp_vzictime.time_seconds % 60; + + fprintf (fp, "%2i %s %04i\t%2i:%02i:%02i", + tmp_vzictime.day_number, months[tmp_vzictime.month], + tmp_vzictime.year, hour, minute, second); + } + + fprintf (fp, "\t%s", format_tz_offset (vzictime->walloff, FALSE)); + + fprintf (fp, "\n"); +} + + +void +ensure_directory_exists (char *directory) +{ + struct stat filestat; + + if (stat (directory, &filestat) != 0) { + /* If the directory doesn't exist, try to create it. */ + if (errno == ENOENT) { + if (mkdir (directory, 0777) != 0) { + fprintf (stderr, "Can't create directory: %s\n", directory); + exit (1); + } + } else { + fprintf (stderr, "Error calling stat() on directory: %s\n", directory); + exit (1); + } + } else if (!S_ISDIR (filestat.st_mode)) { + fprintf (stderr, "Can't create directory, already exists: %s\n", + directory); + exit (1); + } +} + + +static void +expand_tzid_prefix (void) +{ + char *src, *dest; + char date_buf[16]; + char ch1, ch2; + time_t t; + struct tm *tm; + + /* Get today's date as a string in the format "YYYYMMDD". */ + t = time (NULL); + tm = localtime (&t); + sprintf (date_buf, "%4i%02i%02i", tm->tm_year + 1900, + tm->tm_mon + 1, tm->tm_mday); + + src = TZIDPrefix; + dest = TZIDPrefixExpanded; + + while (ch1 = *src++) { + + /* Look for a '%'. */ + if (ch1 == '%') { + ch2 = *src++; + + if (ch2 == 'D') { + /* '%D' gets expanded into the date string. */ + strcpy (dest, date_buf); + dest += strlen (dest); + } else if (ch2 == '%') { + /* '%%' gets converted into one '%'. */ + *dest++ = '%'; + } else { + /* Anything else is output as is. */ + *dest++ = '%'; + *dest++ = ch2; + } + } else { + *dest++ = ch1; + } + } + +#if 0 + printf ("TZID : %s\n", TZIDPrefix); + printf ("Expanded: %s\n", TZIDPrefixExpanded); +#endif +} |