From 98d5ed5e7357659951a067eb8e396be9c2c59a58 Mon Sep 17 00:00:00 2001 From: Lorenz Meier Date: Fri, 23 May 2014 13:41:27 +0200 Subject: sdlog2: Fix GPS sat offset math --- src/modules/sdlog2/sdlog2.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/src/modules/sdlog2/sdlog2.c b/src/modules/sdlog2/sdlog2.c index 873f04828..b6b039d26 100644 --- a/src/modules/sdlog2/sdlog2.c +++ b/src/modules/sdlog2/sdlog2.c @@ -1069,9 +1069,13 @@ int sdlog2_thread_main(int argc, char *argv[]) memset(&log_msg.body.log_GS0A, 0, sizeof(log_msg.body.log_GS0A)); /* fill set A */ for (unsigned i = 0; i < gps_msg_max_snr; i++) { - if (buf_gps_pos.satellite_prn[i] < log_max_snr) { + + int satindex = buf_gps_pos.satellite_prn[i] - 1; + + /* handles index exceeding and wraps to to arithmetic errors */ + if ((satindex >= 0) && (satindex < log_max_snr)) { /* map satellites by their ID so that logs from two receivers can be compared */ - log_msg.body.log_GS0A.satellite_snr[buf_gps_pos.satellite_prn[i]] = buf_gps_pos.satellite_snr[i]; + log_msg.body.log_GS0A.satellite_snr[satindex] = buf_gps_pos.satellite_snr[i]; } } LOGBUFFER_WRITE_AND_COUNT(GS0A); @@ -1080,9 +1084,14 @@ int sdlog2_thread_main(int argc, char *argv[]) memset(&log_msg.body.log_GS0B, 0, sizeof(log_msg.body.log_GS0B)); /* fill set B */ for (unsigned i = 0; i < gps_msg_max_snr; i++) { - if (buf_gps_pos.satellite_prn[i] < log_max_snr) { + + /* get second bank of satellites, thus deduct bank size from index */ + int satindex = buf_gps_pos.satellite_prn[i] - 1 - log_max_snr; + + /* handles index exceeding and wraps to to arithmetic errors */ + if ((satindex >= 0) && (satindex < log_max_snr)) { /* map satellites by their ID so that logs from two receivers can be compared */ - log_msg.body.log_GS0B.satellite_snr[buf_gps_pos.satellite_prn[i]] = buf_gps_pos.satellite_snr[i]; + log_msg.body.log_GS0B.satellite_snr[satindex] = buf_gps_pos.satellite_snr[i]; } } LOGBUFFER_WRITE_AND_COUNT(GS0B); -- cgit v1.2.3