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-rw-r--r--libmap/tz.c399
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diff --git a/libmap/tz.c b/libmap/tz.c
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+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
+/* Generic timezone utilities.
+ *
+ * Copyright (C) 2000-2001 Ximian, Inc.
+ *
+ * Authors: Hans Petter Jansson <hpj@ximian.com>
+ *
+ * Largely based on Michael Fulbright's work on Anaconda.
+ *
+ * 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.
+ */
+
+
+#include <glib.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <time.h>
+#include <math.h>
+#include <string.h>
+#include "tz.h"
+
+
+/* Forward declarations for private functions */
+
+static float convert_pos (gchar *pos, int digits);
+static int compare_country_names (const void *a, const void *b);
+static void sort_locations_by_country (GPtrArray *locations);
+static gchar * tz_data_file_get (void);
+
+
+/* ---------------- *
+ * Public interface *
+ * ---------------- */
+TzDB *
+tz_load_db (void)
+{
+ gchar *tz_data_file;
+ TzDB *tz_db;
+ FILE *tzfile;
+ char buf[4096];
+
+ tz_data_file = tz_data_file_get ();
+ if (!tz_data_file) {
+ g_warning ("Could not get the TimeZone data file name");
+ return NULL;
+ }
+ tzfile = fopen (tz_data_file, "r");
+ if (!tzfile) {
+ g_warning ("Could not open *%s*\n", tz_data_file);
+ g_free (tz_data_file);
+ return NULL;
+ }
+
+ tz_db = g_new0 (TzDB, 1);
+ tz_db->locations = g_ptr_array_new ();
+
+ while (fgets (buf, sizeof(buf), tzfile))
+ {
+ gchar **tmpstrarr;
+ gchar *latstr, *lngstr, *p;
+ TzLocation *loc;
+
+ if (*buf == '#') continue;
+
+ g_strchomp(buf);
+ tmpstrarr = g_strsplit(buf,"\t", 6);
+
+ latstr = g_strdup (tmpstrarr[1]);
+ p = latstr + 1;
+ while (*p != '-' && *p != '+') p++;
+ lngstr = g_strdup (p);
+ *p = '\0';
+
+ loc = g_new0 (TzLocation, 1);
+ loc->country = g_strdup (tmpstrarr[0]);
+ loc->zone = g_strdup (tmpstrarr[2]);
+ loc->latitude = convert_pos (latstr, 2);
+ loc->longitude = convert_pos (lngstr, 3);
+
+#ifdef __sun
+ if (tmpstrarr[3] && *tmpstrarr[3] == '-' && tmpstrarr[4])
+ loc->comment = g_strdup (tmpstrarr[4]);
+
+ if (tmpstrarr[3] && *tmpstrarr[3] != '-' && !islower(loc->zone)) {
+ TzLocation *locgrp;
+
+ /* duplicate entry */
+ locgrp = g_new0 (TzLocation, 1);
+ locgrp->country = g_strdup (tmpstrarr[0]);
+ locgrp->zone = g_strdup (tmpstrarr[3]);
+ locgrp->latitude = convert_pos (latstr, 2);
+ locgrp->longitude = convert_pos (lngstr, 3);
+ locgrp->comment = (tmpstrarr[4]) ? g_strdup (tmpstrarr[4]) : NULL;
+
+ g_ptr_array_add (tz_db->locations, (gpointer) locgrp);
+ }
+#else
+ loc->comment = (tmpstrarr[3]) ? g_strdup(tmpstrarr[3]) : NULL;
+#endif
+
+ g_ptr_array_add (tz_db->locations, (gpointer) loc);
+
+ g_free (latstr);
+ g_free (lngstr);
+ g_strfreev (tmpstrarr);
+ }
+
+ fclose (tzfile);
+
+ /* now sort by country */
+ sort_locations_by_country (tz_db->locations);
+
+ g_free (tz_data_file);
+
+ return tz_db;
+}
+
+static void
+tz_location_free (TzLocation *loc)
+{
+ g_free (loc->country);
+ g_free (loc->zone);
+ g_free (loc->comment);
+
+ g_free (loc);
+}
+
+void
+tz_db_free (TzDB *db)
+{
+ g_ptr_array_foreach (db->locations, (GFunc) tz_location_free, NULL);
+ g_ptr_array_free (db->locations, TRUE);
+ g_free (db);
+}
+
+static gint
+sort_locations (TzLocation *a,
+ TzLocation *b)
+{
+ if (a->dist > b->dist)
+ return 1;
+
+ if (a->dist < b->dist)
+ return -1;
+
+ return 0;
+}
+
+static gdouble
+convert_longtitude_to_x (gdouble longitude, gint map_width)
+{
+ const gdouble xdeg_offset = -6;
+ gdouble x;
+
+ x = (map_width * (180.0 + longitude) / 360.0)
+ + (map_width * xdeg_offset / 180.0);
+
+ return x;
+}
+
+static gdouble
+radians (gdouble degrees)
+{
+ return (degrees / 360.0) * G_PI * 2;
+}
+
+static gdouble
+convert_latitude_to_y (gdouble latitude, gdouble map_height)
+{
+ gdouble bottom_lat = -59;
+ gdouble top_lat = 81;
+ gdouble top_per, y, full_range, top_offset, map_range;
+
+ top_per = top_lat / 180.0;
+ y = 1.25 * log (tan (G_PI_4 + 0.4 * radians (latitude)));
+ full_range = 4.6068250867599998;
+ top_offset = full_range * top_per;
+ map_range = fabs (1.25 * log (tan (G_PI_4 + 0.4 * radians (bottom_lat))) - top_offset);
+ y = fabs (y - top_offset);
+ y = y / map_range;
+ y = y * map_height;
+ return y;
+}
+
+GPtrArray *
+tz_get_locations (TzDB *db)
+{
+ return db->locations;
+}
+
+
+gchar *
+tz_location_get_country (TzLocation *loc)
+{
+ return loc->country;
+}
+
+
+gchar *
+tz_location_get_zone (TzLocation *loc)
+{
+ return loc->zone;
+}
+
+
+gchar *
+tz_location_get_comment (TzLocation *loc)
+{
+ return loc->comment;
+}
+
+
+void
+tz_location_get_position (TzLocation *loc, double *longitude, double *latitude)
+{
+ *longitude = loc->longitude;
+ *latitude = loc->latitude;
+}
+
+glong
+tz_location_get_utc_offset (TzLocation *loc)
+{
+ TzInfo *tz_info;
+ glong offset;
+
+ tz_info = tz_info_from_location (loc);
+ offset = tz_info->utc_offset;
+ tz_info_free (tz_info);
+ return offset;
+}
+
+gint
+tz_location_set_locally (TzLocation *loc)
+{
+ time_t curtime;
+ struct tm *curzone;
+ gboolean is_dst = FALSE;
+ gint correction = 0;
+
+ g_return_val_if_fail (loc != NULL, 0);
+ g_return_val_if_fail (loc->zone != NULL, 0);
+
+ curtime = time (NULL);
+ curzone = localtime (&curtime);
+ is_dst = curzone->tm_isdst;
+
+ setenv ("TZ", loc->zone, 1);
+#if 0
+ curtime = time (NULL);
+ curzone = localtime (&curtime);
+
+ if (!is_dst && curzone->tm_isdst) {
+ correction = (60 * 60);
+ }
+ else if (is_dst && !curzone->tm_isdst) {
+ correction = 0;
+ }
+#endif
+
+ return correction;
+}
+
+TzInfo *
+tz_info_from_location (TzLocation *loc)
+{
+ TzInfo *tzinfo;
+ time_t curtime;
+ struct tm *curzone;
+
+ g_return_val_if_fail (loc != NULL, NULL);
+ g_return_val_if_fail (loc->zone != NULL, NULL);
+
+ setenv ("TZ", loc->zone, 1);
+
+#if 0
+ tzset ();
+#endif
+ tzinfo = g_new0 (TzInfo, 1);
+
+ curtime = time (NULL);
+ curzone = localtime (&curtime);
+
+#ifndef __sun
+ /* Currently this solution doesnt seem to work - I get that */
+ /* America/Phoenix uses daylight savings, which is wrong */
+ tzinfo->tzname_normal = g_strdup (curzone->tm_zone);
+ if (curzone->tm_isdst)
+ tzinfo->tzname_daylight =
+ g_strdup (&curzone->tm_zone[curzone->tm_isdst]);
+ else
+ tzinfo->tzname_daylight = NULL;
+
+ tzinfo->utc_offset = curzone->tm_gmtoff;
+#else
+ tzinfo->tzname_normal = NULL;
+ tzinfo->tzname_daylight = NULL;
+ tzinfo->utc_offset = 0;
+#endif
+
+ tzinfo->daylight = curzone->tm_isdst;
+
+ return tzinfo;
+}
+
+
+void
+tz_info_free (TzInfo *tzinfo)
+{
+ g_return_if_fail (tzinfo != NULL);
+
+ if (tzinfo->tzname_normal) g_free (tzinfo->tzname_normal);
+ if (tzinfo->tzname_daylight) g_free (tzinfo->tzname_daylight);
+ g_free (tzinfo);
+}
+
+/* ----------------- *
+ * Private functions *
+ * ----------------- */
+
+static gchar *
+tz_data_file_get (void)
+{
+ gchar *file;
+
+ file = g_strdup (TZ_DATA_FILE);
+
+ return file;
+}
+
+static float
+convert_pos (gchar *pos, int digits)
+{
+ gchar whole[10];
+ gchar *fraction;
+ gint i;
+ float t1, t2;
+
+ if (!pos || strlen(pos) < 4 || digits > 9) return 0.0;
+
+ for (i = 0; i < digits + 1; i++) whole[i] = pos[i];
+ whole[i] = '\0';
+ fraction = pos + digits + 1;
+
+ t1 = g_strtod (whole, NULL);
+ t2 = g_strtod (fraction, NULL);
+
+ if (t1 >= 0.0) return t1 + t2/pow (10.0, strlen(fraction));
+ else return t1 - t2/pow (10.0, strlen(fraction));
+}
+
+
+#if 0
+
+/* Currently not working */
+static void
+free_tzdata (TzLocation *tz)
+{
+
+ if (tz->country)
+ g_free(tz->country);
+ if (tz->zone)
+ g_free(tz->zone);
+ if (tz->comment)
+ g_free(tz->comment);
+
+ g_free(tz);
+}
+#endif
+
+
+static int
+compare_country_names (const void *a, const void *b)
+{
+ const TzLocation *tza = * (TzLocation **) a;
+ const TzLocation *tzb = * (TzLocation **) b;
+
+ return strcmp (tza->zone, tzb->zone);
+}
+
+
+static void
+sort_locations_by_country (GPtrArray *locations)
+{
+ qsort (locations->pdata, locations->len, sizeof (gpointer),
+ compare_country_names);
+}