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-rw-r--r--libosmocore/src/gsm_utils.c210
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diff --git a/libosmocore/src/gsm_utils.c b/libosmocore/src/gsm_utils.c
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+++ b/libosmocore/src/gsm_utils.c
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+/*
+ * (C) 2008 by Daniel Willmann <daniel@totalueberwachung.de>
+ * (C) 2009 by Holger Hans Peter Freyther <zecke@selfish.org>
+ * (C) 2009 by Harald Welte <laforge@gnumonks.org>
+ *
+ * All Rights Reserved
+ *
+ * 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.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+//#include <openbsc/gsm_data.h>
+#include <osmocore/utils.h>
+#include <osmocore/gsm_utils.h>
+
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <errno.h>
+
+/* GSM 03.38 6.2.1 Charachter packing */
+int gsm_7bit_decode(char *text, const u_int8_t *user_data, u_int8_t length)
+{
+ int i = 0;
+ int l = 0;
+
+ /* FIXME: We need to account for user data headers here */
+ i += l;
+ for (; i < length; i ++)
+ *(text ++) =
+ ((user_data[(i * 7 + 7) >> 3] <<
+ (7 - ((i * 7 + 7) & 7))) |
+ (user_data[(i * 7) >> 3] >>
+ ((i * 7) & 7))) & 0x7f;
+ *text = '\0';
+
+ return i - l;
+}
+
+
+/* GSM 03.38 6.2.1 Charachter packing */
+int gsm_7bit_encode(u_int8_t *result, const char *data)
+{
+ int i,j = 0;
+ unsigned char ch1, ch2;
+ int shift = 0;
+
+ for ( i=0; i<strlen(data); i++ ) {
+
+ ch1 = data[i] & 0x7F;
+ ch1 = ch1 >> shift;
+ ch2 = data[(i+1)] & 0x7F;
+ ch2 = ch2 << (7-shift);
+
+ ch1 = ch1 | ch2;
+
+ result[j++] = ch1;
+
+ shift++;
+
+ if ((shift == 7) && (i+1<strlen(data))) {
+ shift = 0;
+ i++;
+ }
+ }
+
+ return i;
+}
+
+/* determine power control level for given dBm value, as indicated
+ * by the tables in chapter 4.1.1 of GSM TS 05.05 */
+int ms_pwr_ctl_lvl(enum gsm_band band, unsigned int dbm)
+{
+ switch (band) {
+ case GSM_BAND_450:
+ case GSM_BAND_480:
+ case GSM_BAND_750:
+ case GSM_BAND_900:
+ case GSM_BAND_810:
+ case GSM_BAND_850:
+ if (dbm >= 39)
+ return 0;
+ else if (dbm < 5)
+ return 19;
+ else {
+ /* we are guaranteed to have (5 <= dbm < 39) */
+ return 2 + ((39 - dbm) / 2);
+ }
+ break;
+ case GSM_BAND_1800:
+ if (dbm >= 36)
+ return 29;
+ else if (dbm >= 34)
+ return 30;
+ else if (dbm >= 32)
+ return 31;
+ else if (dbm == 31)
+ return 0;
+ else {
+ /* we are guaranteed to have (0 <= dbm < 31) */
+ return (30 - dbm) / 2;
+ }
+ break;
+ case GSM_BAND_1900:
+ if (dbm >= 33)
+ return 30;
+ else if (dbm >= 32)
+ return 31;
+ else if (dbm == 31)
+ return 0;
+ else {
+ /* we are guaranteed to have (0 <= dbm < 31) */
+ return (30 - dbm) / 2;
+ }
+ break;
+ }
+ return -EINVAL;
+}
+
+int ms_pwr_dbm(enum gsm_band band, u_int8_t lvl)
+{
+ lvl &= 0x1f;
+
+ switch (band) {
+ case GSM_BAND_450:
+ case GSM_BAND_480:
+ case GSM_BAND_750:
+ case GSM_BAND_900:
+ case GSM_BAND_810:
+ case GSM_BAND_850:
+ if (lvl < 2)
+ return 39;
+ else if (lvl < 20)
+ return 39 - ((lvl - 2) * 2) ;
+ else
+ return 5;
+ break;
+ case GSM_BAND_1800:
+ if (lvl < 16)
+ return 30 - (lvl * 2);
+ else if (lvl < 29)
+ return 0;
+ else
+ return 36 - ((lvl - 29) * 2);
+ break;
+ case GSM_BAND_1900:
+ if (lvl < 16)
+ return 30 - (lvl * 2);
+ else if (lvl < 30)
+ return -EINVAL;
+ else
+ return 33 - (lvl - 30);
+ break;
+ }
+ return -EINVAL;
+}
+
+/* According to TS 08.05 Chapter 8.1.4 */
+int rxlev2dbm(u_int8_t rxlev)
+{
+ if (rxlev > 63)
+ rxlev = 63;
+
+ return -110 + rxlev;
+}
+
+/* According to TS 08.05 Chapter 8.1.4 */
+u_int8_t dbm2rxlev(int dbm)
+{
+ int rxlev = dbm + 110;
+
+ if (rxlev > 63)
+ rxlev = 63;
+ else if (rxlev < 0)
+ rxlev = 0;
+
+ return rxlev;
+}
+
+#include <execinfo.h>
+void generate_backtrace()
+{
+ int i, nptrs;
+ void *buffer[100];
+ char **strings;
+
+ nptrs = backtrace(buffer, ARRAY_SIZE(buffer));
+ printf("backtrace() returned %d addresses\n", nptrs);
+
+ strings = backtrace_symbols(buffer, nptrs);
+ if (!strings)
+ return;
+
+ for (i = 1; i < nptrs; i++)
+ printf("%s\n", strings[i]);
+
+ free(strings);
+}