Tvheadend

Previously, this problem was not. Now it happens all the time...

Message from kernel:

do_page_fault(): sending SIGSEGV to tvh:tcp-start for invalid read access from 0000001a
epc = 76dfdc5c in libc-2.27.so[76d79000+175000]
ra  = 76dc2e38 in libc-2.27.so[76d79000+175000]

Message from gdb:

~ # gdb --args /opt/usr/sbin/tvheadend -C -B -S -u root -g root -c /opt/etc/tvheadend --satip_bindaddr 0.0.0.0 --satip_rtsp -1
GNU gdb (GDB) 8.0.1
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License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
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Type "show configuration" for configuration details.
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Reading symbols from /opt/usr/sbin/tvheadend...done.
(gdb) r
Starting program: /opt/usr/sbin/tvheadend -C -B -S -u root -g root -c /opt/etc/tvheadend --satip_bindaddr 0.0.0.0 --satip_rtsp -1
warning: File "/opt/lib/libthread_db-1.0.so" auto-loading has been declined by your `auto-load safe-path' set to "$debugdir:$datadir/auto-load".
To enable execution of this file add
        add-auto-load-safe-path /opt/lib/libthread_db-1.0.so
line to your configuration file "/opt/root/.gdbinit".
To completely disable this security protection add
        set auto-load safe-path /
line to your configuration file "/opt/root/.gdbinit".
For more information about this security protection see the
"Auto-loading safe path" section in the GDB manual.  E.g., run from the shell:
        info "(gdb)Auto-loading safe path" 
warning: Unable to find libthread_db matching inferior's thread library, thread debugging will not be available.
[New LWP 13706]
2018-03-24 21:03:19.030 [   INFO] main: Log started
[New LWP 13707]
[New LWP 13708]
2018-03-24 21:03:19.050 [   INFO] http: Starting HTTP server 0.0.0.0:9981
2018-03-24 21:03:19.050 [   INFO] htsp: Starting HTSP server 0.0.0.0:9982
[New LWP 13709]
2018-03-24 21:03:19.057 [   INFO] config: loaded
[New LWP 13710]
[New LWP 13711]
[New LWP 13712]
2018-03-24 21:03:19.061 [   INFO] config: scanfile (re)initialization with path <none>
[New LWP 13713]
[New LWP 13714]
[New LWP 13715]
[New LWP 13716]
[New LWP 13717]
[New LWP 13718]
2018-03-24 21:03:19.079 [   INFO] dvr: Creating new configuration ''
2018-03-24 21:03:19.080 [  ERROR] access: No access entries loaded
[New LWP 13719]
[New LWP 13720]
[New LWP 13721]
[New LWP 13722]
2018-03-24 21:03:19.087 [   INFO] csa: Using 32bit parallel descrambling
2018-03-24 21:03:19.088 [   INFO] descrambler: adding CAID 2600 as constant crypto-word (BISS)
2018-03-24 21:03:19.089 [   INFO] epggrab: module eit created
2018-03-24 21:03:19.089 [   INFO] epggrab: module uk_freesat created
2018-03-24 21:03:19.090 [   INFO] epggrab: module uk_freeview created
2018-03-24 21:03:19.090 [   INFO] epggrab: module nz_freeview created
2018-03-24 21:03:19.091 [   INFO] epggrab: module viasat_baltic created
2018-03-24 21:03:19.091 [   INFO] epggrab: module Bulsatcom_39E created
2018-03-24 21:03:19.092 [   INFO] epggrab: module psip created
2018-03-24 21:03:19.123 [   INFO] epggrab: module opentv-skyit created
2018-03-24 21:03:19.131 [   INFO] epggrab: module opentv-skyuk created
2018-03-24 21:03:19.133 [   INFO] epggrab: module opentv-skynz created
2018-03-24 21:03:19.134 [   INFO] epggrab: module opentv-ausat created
2018-03-24 21:03:19.136 [   INFO] epggrab: module pyepg created
2018-03-24 21:03:19.136 [   INFO] epggrab: module xmltv created
2018-03-24 21:03:19.141 [   INFO] spawn: Executing "/opt/usr/sbin/tv_grab_ru" 
2018-03-24 21:03:19.150 [   INFO] epggrab: module /opt/usr/sbin/tv_grab_ru created
[New LWP 13724]
[New LWP 13725]
2018-03-24 21:03:19.156 [ NOTICE] START: HTS Tvheadend version 4.2.5~1997b34-NDMS-5 started, running as PID:13703 UID:0 GID:0, CWD:/opt/root CNF:/opt/etc/tvheadend                                                                                                                                                              
[New LWP 13726]
[New LWP 13727]
[New LWP 13728]
[New LWP 13729]
2018-03-24 21:03:20.322 [WARNING] satips: SAT>IP server announces an empty tuner list to a client 127.0.0.1 (missing tuner settings - global config)                                                                                                                                                                             

Thread 24 "tvh:tcp-start" received signal SIGSEGV, Segmentation fault.
[Switching to LWP 13729]
0x77a52c5c in strlen () from /opt/lib/libc.so.6
(gdb) print satip_server_rtsp_port
$1 = -1
(gdb) print http_server_ip
$2 = 0x0

The problem occurs when calling the function satip_server_http_xml() line 199 in src/satip/server.c. If http_server_ip NULL, also satip_server_conf.satip_uuid NULL, see function satip_server_register() line 999, so the called function snprintf() causes segfault.

I made patch that solves this problem.