Tvheadend

The file linux/dvb/version.h must match the file in kernel which is run on the device. I would probably use some older <5.0 header file to compile tvh which you may find in vendor/dvb-api directory (3.2 for example), because it seems that the compability layer for 32-bit applications does not work correctly in your case.

Hi Jaroslav and thank you VERY MUCH for answering.

The file linux/dvb/version.h must match the file in kernel which is run on the device.

I thought the same intially and it's the reason why I actually post the version.h information.

However on the picture below you can see the original kernel sources of the QNAP and the version is 5.5, i.e. newer than the version that I used on the build virtual machine (5.1).

When you say the version must match, you mean exactly or an older version.h version is OK too?
And as the 32-bit is working, is the 32-bit compatibility layer conflicting with the version.h file?

I would probably use some older <5.0 header file to compile tvh which you may find in vendor/dvb-api directory (3.2 for example), because it seems that the compability layer for 32-bit applications does not work correctly in your case.

I've tried. On the build VM I deleted the /usr/include/linux/dvb folder and replaced it with ./vendor/dvb-api/3.2/linux/dvb so it should be correct.
But after a make clean and a new configure I'm not able to compile the 74c563f version anymore:

CC              src/input/mpegts/linuxdvb/linuxdvb.o
CC              src/input/mpegts/linuxdvb/linuxdvb_adapter.o
CC              src/input/mpegts/linuxdvb/linuxdvb_frontend.o
cc1: warnings being treated as errors
src/input/mpegts/linuxdvb/linuxdvb_frontend.c:921: error: ‘linuxdvb2tvh’ defined but not used
make: *** [/root/tvheadend/tvheadend/build.linux/src/input/mpegts/linuxdvb/linuxdvb_frontend.o] Error 1

Finally - if I'm not misusing your patience - I moved to the DVB api v5 because of supporting DVB-S2 with 8PSK, which I think couldn't be done with v3.2. What would be the correct way to use DVB-S2 with 8PSK then?

The compilation issue should be fixed in v3.9-2486-g4a9dfec for ver 3.2.

In this case 5.5 dvb headers should be used (include/linux/dvb/*.h), but it won't solve the DVB_CLEAR issue, if the 32-bit support in the kernel is broken - the kernel must be fixed. Basically, it seems that the ioctl is not converted properly between the 32-bit request and 64-bit kernel driver (it's called as the compat layer in the kernel). I'm sure that there is a patch which fixes this issue for linuxdvb. Just try to search in the kernel sources.

In this case 5.5 dvb headers should be used (include/linux/dvb/*.h), but it won't solve the DVB_CLEAR issue, if the 32-bit support in the kernel is broken - the kernel must be fixed.

OK, we tried the same version (3.9.2293~g74c563f) compiled with v5.5 DVB headers from TVHeadend vendor folder and the error is still there:

2015-02-11 11:46:41.777 [ NOTICE] START: HTS Tvheadend version 3.9.2293~g74c563f started, running as PID:31803 UID:0 GID:0, CWD:/root CNF:/share/CACHEDEV1_DATA/.qpkg/TVHeadend/config
...
2015-02-11 11:48:51.000 [   INFO] mpegts: 698MHz in West Midlands - tuning on DiBcom 7000PC : DVB-T #0
2015-02-11 11:48:51.000 [  DEBUG] linuxdvb: DiBcom 7000PC : DVB-T #0 - starting 698MHz in West Midlands
2015-02-11 11:48:51.000 [  ERROR] linuxdvb: DiBcom 7000PC : DVB-T #0 - DTV_CLEAR failed [e=Inappropriate ioctl for device]
2015-02-11 11:48:51.000 [WARNING] mpegts: 698MHz in West Midlands - failed to start on DiBcom 7000PC : DVB-T #0, try another

How can I know which version of the DVB headers TVHeadend uses from a binary? I mean, how can I differentiate the two binaries that I've compiled as the current one should have 5.5 dvb headers while the older one should have 5.1?

Basically, it seems that the ioctl is not converted properly between the 32-bit request and 64-bit kernel driver (it's called as the compat layer in the kernel).

OK, that sound right, but why older TVHeadend binaries such as v3.5.126~g8c5f9af are working then? The kernel modules are the same and the running kernel driver and its compat layer should be bugged too, but TVHeadend is able to workaround in some ways.
I know that the DVB "core" of TVHeadend has been rewritten recently, I'm just asking if this is something we can investigate...

I'm sure that there is a patch which fixes this issue for linuxdvb. Just try to search in the kernel sources.

Sorry, I'm not very skilled on this subject (but opened to suggestions of course!).
Where am I supposed to look for kernel patches? I searched for ".patch" files on the QNAP GPLs (those on the image posted on the previous message) but there is nothing related to DVB.
I tried also HERE but cannot find anything related to dvb-core.

The compilation issue should be fixed in v3.9-2486-g4a9dfec for ver 3.2.

Unfortunately, it is not... Here it is what I get using that version:

root@debian-x86:~/tvheadend/tvheadend# git reset --hard 4a9dfec 
HEAD is now at 4a9dfec linuxdvb: fix compilation for dvb < 5.0
root@debian-x86:~/tvheadend/tvheadend# make clean
root@debian-x86:~/tvheadend/tvheadend# ./configure --disable-avahi --enable-bundle --disable-libav --disable-dbus_1 --release
Checking support/features
  checking for cc execinfo.h ...                    ok
  checking for cc -mmmx ...                         ok
  checking for cc -msse2 ...                        ok
  checking for cc getloadavg ...                    ok
  checking for cc atomic64 ...                      ok
  checking for cc lockowner ...                     ok
  checking for cc qsort_r ...                       ok
  checking for cc recvmmsg ...                      fail
  checking for cc libiconv ...                      fail
  checking for py module gzip ...                   ok
  checking for bzip2 ...                            ok
  checking for pkg openssl  ...                     ok (detected 0.9.8o)
  checking for cc linux/dvb/version.h ...           ok
  checking for cc libhdhomerun/hdhomerun.h ...      fail
  checking for pkg zlib  ...                        ok (detected 1.2.3.4)
  checking for pkg liburiparser  ...                fail (detected <none>)
  checking for cc sys/inotify.h ...                 ok
  fetching dvb-scan files ...                       ok

Compiler:
  Using C compiler:                        cc
  Build for arch:                          i686

Binaries:
  Using PYTHON:                            python

Options:
  cwc                                      yes
  capmt                                    yes
  constcw                                  yes
  v4l                                      no
  linuxdvb                                 yes
  satip_client                             yes
  hdhomerun_client                         no
  hdhomerun_static                         no
  iptv                                     yes
  tsfile                                   yes
  dvbscan                                  yes
  timeshift                                yes
  trace                                    yes
  imagecache                               yes
  avahi                                    no
  zlib                                     yes
  libav                                    no
  libffmpeg_static                         no
  inotify                                  yes
  epoll                                    yes
  uriparser                                no
  ccache                                   no
  tvhcsa                                   yes
  bundle                                   yes
  dvbcsa                                   no
  kqueue                                   no
  dbus_1                                   no
  android                                  no
  tsdebug                                  no
  execinfo                                 yes
  mmx                                      yes
  sse2                                     yes
  getloadavg                               yes
  atomic64                                 yes
  lockowner                                yes
  qsort_r                                  yes
  py_gzip                                  yes
  bin_bzip2                                yes
  ssl                                      yes
  linuxdvbapi                              yes
  upnp                                     yes
  inotify_h                                yes
  mpegts                                   yes
  mpegps                                   no
  mpegts_dvb                               yes

Packages:
  openssl                                  0.9.8o
  zlib                                     1.2.3.4

Installation paths:
  Prefix:                                  /usr/local
  Binaries:                                ${prefix}/bin
  Libraries:                               ${prefix}/lib
  Data files:                              ${prefix}/share
  Man pages:                               ${datadir}/man

Final Binary:
  /root/tvheadend/tvheadend/build.linux/tvheadend

Tvheadend Data Directory:
  /usr/local/share/tvheadend

root@debian-x86:~/tvheadend/tvheadend# make
CC              src/version.o
CC              src/uuid.o
CC              src/main.o
CC              src/tvhlog.o
CC              src/idnode.o
CC              src/prop.o
CC              src/utils.o
CC              src/wrappers.o
CC              src/access.o
CC              src/tcp.o
CC              src/udp.o
cc1: warnings being treated as errors
src/udp.c:529: error: no previous prototype for ‘recvmmsg’
make: *** [/root/tvheadend/tvheadend/build.linux/src/udp.o] Error 1

virtual dj wrote:

The compilation issue should be fixed in v3.9-2486-g4a9dfec for ver 3.2.

Unfortunately, it is not... Here it is what I get using that version:
[...]

Fixed in v3.9-2496-gd386ed0 .

Jaroslav Kysela wrote:

Fixed in v3.9-2496-gd386ed0 .

Thanks, the v3.9-2496 now compiles fine with the DVB 3.2 headers.
Unfortunately for all the guys with the 64-bit NAS, it doesn't solve the issue.

The error message on the TVHeadend log has changed, though.
This is what people get with a Dibcom tuner and v3.9-2496:

2015-02-13 11:57:03.000 [   INFO] mpegts: 826MHz in West Midlands - tuning on DiBcom 7000PC : DVB-T #0
2015-02-13 11:57:03.000 [  DEBUG] linuxdvb: DiBcom 7000PC : DVB-T #0 - starting 826MHz in West Midlands
2015-02-13 11:57:03.000 [  ERROR] linuxdvb: DiBcom 7000PC : DVB-T #0 - failed to tune [e=Bad address]
2015-02-13 11:57:03.000 [WARNING] mpegts: 826MHz in West Midlands - failed to start on DiBcom 7000PC : DVB-T #0, try another

2015-02-13 17:44:56.005 linuxdvb: HDHomeRun ATSC 105134FA-0 : ATSC #0 - failed to tune [e=Bad address]
2015-02-13 17:44:56.005 mpegts: 63.28MHz in USTV - failed to start on HDHomeRun ATSC 105134FA-0 : ATSC #0, try another
2015-02-13 17:44:56.005 mpegts: 57.28MHz in USTV - tuning on HDHomeRun ATSC 105134FA-0 : ATSC #0
2015-02-13 17:44:56.005 linuxdvb: HDHomeRun ATSC 105134FA-0 : ATSC #0 - failed to tune [e=Bad address]
2015-02-13 17:44:56.005 mpegts: 57.28MHz in USTV - failed to start on HDHomeRun ATSC 105134FA-0 : ATSC #0, try another

So basically DTV_CLEAR failed [e=Inappropriate ioctl for device] has becomed failed to tune [e=Bad address].

All the 64-bit QNAP users and I are available for any test you would like us to perform, but we really like to have TVHeadend working, as it was working in the past with the same OS and kernel.
Please help!

Compile tvheadend with --enable-trace and provide log "--trace linuxdvb,diseqc -l <logfile>" (command line options) for working and non-working cases.

Hi Jaroslav, are the logs OK? Did you have time to identify a possible cause?
We're here if you need further data, just ask!

Thank you

Unfortunately, the "DTV_CLEAR failed [e=Inappropriate ioctl for device]" error is present in A.txt and C.txt. The linuxdvb subsystem v5.0+ should be able to handle this ioctl.

In E.txt tvheadend v3.5-126 is used. This version uses always old ioctl for DVB-T (FE_SET_FRONTEND), but recent tvh uses 5.0+ API - FE_SET_PROPERTY ioctl - also for DVB-T.

Do you have kernel sources?

In E.txt tvheadend v3.5-126 is used. This version uses always old ioctl for DVB-T (FE_SET_FRONTEND), but recent tvh uses 5.0+ API - FE_SET_PROPERTY ioctl - also for DVB-T.

Yes, definitely this difference should be the culprit.

Do you have kernel sources?

You can download the sources from the QNAP GPL 3.8.0 here.
Inside the file GPL_TS-20130601-3.8.x.tar.gz you can find the kernel sources in GPL_TS/src/linux_3.4.6.

Hi Jaroslav, have you got any news on this subject?
Thanks.

Yes, it looks like that FE_SET_PROPERTY has no compatibility converter, so it's impossible to use 32-bit ioctl on 64-bit kernel.

FE_SET_FRONTEND has limitations.

I would try to resolve the 64-bit compilation issue. Have you tried the static linking to resolve the problems with libraries ?

Yes, it looks like that FE_SET_PROPERTY has no compatibility converter, so it's impossible to use 32-bit ioctl on 64-bit kernel.

FE_SET_FRONTEND has limitations.

That's bad news.

I would try to resolve the 64-bit compilation issue.

I had compiled the pure 64-bit version of TVHeadend on a 64-bit Debian VM with the following switches:

./configure --disable-avahi --enable-bundle --disable-libav --disable-dbus_1 --release

On the VM it compiled and worked correctly of course, but when moving to the QNAP (together with the complete libc, due to the old version available on the NAS) there were errors.
For example, even when providing this command line:

tvheadend -c ${QPKG_DIR}/config -d -u admin -g administrators -C

2014-12-27 17:54:55.040 [   INFO] main: Log started
2014-12-27 17:54:55.040 [  ERROR] tcp: bind: *: Address already in use
2014-12-27 17:54:55.040 [  ERROR] tcp: bind: *: Address already in use
2014-12-27 17:54:55.041 [WARNING] START: configuration path /share/CACHEDEV1_DATA/.qpkg/TVHeadend/config is not r/w for UID:1 GID:1 [e=Permission denied], settings will not be saved

Then we abandoned the 64-bit compilation because we though it was better to focus on the 32-bit, as it always worked in the past.

Have you tried the static linking to resolve the problems with libraries ?

Can you suggest how should I do it?
At the moment using a Debian x64 squeeze VM I get:

root@debian-x64:~/tvheadend/tvheadend# git reset --hard d386ed0
root@debian-x64:~/tvheadend/tvheadend# make clean
root@debian-x64:~/tvheadend/tvheadend# ./configure --disable-avahi --enable-bundle --disable-libav --disable-dbus_1 --release
Checking support/features
  checking for cc execinfo.h ...                    ok
  checking for cc -mmmx ...                         ok
  checking for cc -msse2 ...                        ok
  checking for cc getloadavg ...                    ok
  checking for cc atomic64 ...                      ok
  checking for cc lockowner ...                     ok
  checking for cc qsort_r ...                       ok
  checking for cc recvmmsg ...                      fail
  checking for cc libiconv ...                      fail
  checking for py module gzip ...                   ok
  checking for bzip2 ...                            ok
  checking for pkg openssl  ...                     ok (detected 0.9.8o)
  checking for cc linux/dvb/version.h ...           ok
  checking for cc libhdhomerun/hdhomerun.h ...      fail
  checking for pkg zlib  ...                        ok (detected 1.2.3.4)
  checking for pkg liburiparser  ...                fail (detected <none>)
  checking for cc sys/inotify.h ...                 ok
  fetching dvb-scan files ...                       ok

Compiler:
  Using C compiler:                        cc
  Build for arch:                          x86_64

Binaries:
  Using PYTHON:                            python

Options:
  cwc                                      yes
  capmt                                    yes
  constcw                                  yes
  v4l                                      no
  linuxdvb                                 yes
  satip_client                             yes
  hdhomerun_client                         no
  hdhomerun_static                         no
  iptv                                     yes
  tsfile                                   yes
  dvbscan                                  yes
  timeshift                                yes
  trace                                    yes
  imagecache                               yes
  avahi                                    no
  zlib                                     yes
  libav                                    no
  libffmpeg_static                         no
  inotify                                  yes
  epoll                                    yes
  uriparser                                no
  ccache                                   no
  tvhcsa                                   yes
  bundle                                   yes
  dvbcsa                                   no
  kqueue                                   no
  dbus_1                                   no
  android                                  no
  tsdebug                                  no
  execinfo                                 yes
  mmx                                      yes
  sse2                                     yes
  getloadavg                               yes
  atomic64                                 yes
  lockowner                                yes
  qsort_r                                  yes
  py_gzip                                  yes
  bin_bzip2                                yes
  ssl                                      yes
  linuxdvbapi                              yes
  upnp                                     yes
  inotify_h                                yes
  mpegts                                   yes
  mpegps                                   no
  mpegts_dvb                               yes

Packages:
  openssl                                  0.9.8o
  zlib                                     1.2.3.4

Installation paths:
  Prefix:                                  /usr/local
  Binaries:                                ${prefix}/bin
  Libraries:                               ${prefix}/lib
  Data files:                              ${prefix}/share
  Man pages:                               ${datadir}/man

Final Binary:
  /root/tvheadend/tvheadend/build.linux/tvheadend

Tvheadend Data Directory:
  /usr/local/share/tvheadend

root@debian-x64:~/tvheadend/tvheadend# make
... omitted ...
CC              src/descrambler/libaesdec/libaesdec.o
MKBUNDLE        bundle.c
CC              bundle.o
CC              tvheadend

root@debian-x64:~/tvheadend/tvheadend# ldd build.linux/tvheadend
        linux-vdso.so.1 =>  (0x00007fffc3375000)
        libssl.so.0.9.8 => /usr/lib/libssl.so.0.9.8 (0x00007fe519aae000)
        libcrypto.so.0.9.8 => /usr/lib/libcrypto.so.0.9.8 (0x00007fe51970d000)
        libz.so.1 => /usr/lib/libz.so.1 (0x00007fe5194f5000)
        libdl.so.2 => /lib/libdl.so.2 (0x00007fe5192f1000)
        libpthread.so.0 => /lib/libpthread.so.0 (0x00007fe5190d5000)
        libm.so.6 => /lib/libm.so.6 (0x00007fe518e52000)
        librt.so.1 => /lib/librt.so.1 (0x00007fe518c4a000)
        libc.so.6 => /lib/libc.so.6 (0x00007fe5188e8000)
        /lib64/ld-linux-x86-64.so.2 (0x00007fe519d0b000)

root@debian-x64:~/tvheadend/tvheadend# gcc -v
Using built-in specs.
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Debian 4.4.5-8' --with-bugurl=file:///usr/share/doc/gcc-4.4/README.Bugs --enable-languages=c,c++,fortran,objc,obj-c++ --prefix=/usr --program-suffix=-4.4 --enable-shared --enable-multiarch --enable-linker-build-id --with-system-zlib --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --with-gxx-include-dir=/usr/include/c++/4.4 --libdir=/usr/lib --enable-nls --enable-clocale=gnu --enable-libstdcxx-debug --enable-objc-gc --with-arch-32=i586 --with-tune=generic --enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu
Thread model: posix
gcc version 4.4.5 (Debian 4.4.5-8)

What does say 'netstat -4an | grep 9981' before start? Also, does have the user with uid 1 and gid 1 access to all directories from the path /share/CACHEDEV1_DATA/.qpkg/TVHeadend/config ?

What does say 'netstat -4an | grep 9981' before start?

It said that there was another TVHeadend "clone" running on the NAS, hence the error.
So ignore that, sorry.

Also, does have the user with uid 1 and gid 1 access to all directories from the path /share/CACHEDEV1_DATA/.qpkg/TVHeadend/config ?

Thank you VERY much. You asked the right thing: the problem that prevented the 64-bit version to run was there!
Even though TVHeadend was launched with:

-u admin -g administrators -C

[~] # id -u root
id: root: No such user
[~] # id -u admin
0
[~] # id -g admin
0
[~] # id -G admin
0 100
[~] # id
uid=0(admin) gid=0(administrators) groups=0(administrators),100(everyone),101(kvm),102(libvirtd)

So running TVHeadend without the "-u" and "-g" switches picked up UID 0 and now the user reports that it's working correctly (and tuning). Is this a bug?
I'm available if you have additional tests to do.

By the way, I was trying to compile the latest version (as I was still running 3.9-2496-gd386ed0) and it fails with:

root@debian-x64:~/tvheadend/tvheadend# make
CC              src/version.o
CC              src/uuid.o
CC              src/main.o
In file included from /root/tvheadend/tvheadend/src/input.h:128,
                 from src/satip/server.h:27,
                 from src/main.c:53:
/root/tvheadend/tvheadend/src/input/mpegts.h:43: error: redefinition of typedef ‘mpegts_psi_section_t’
/root/tvheadend/tvheadend/src/input/mpegts/dvb.h:216: note: previous declaration of ‘mpegts_psi_section_t’ was here
make: *** [/root/tvheadend/tvheadend/build.linux/src/main.o] Error 1

virtual dj wrote:

Also, does have the user with uid 1 and gid 1 access to all directories from the path /share/CACHEDEV1_DATA/.qpkg/TVHeadend/config ?

Thank you VERY much. You asked the right thing: the problem that prevented the 64-bit version to run was there!
Even though TVHeadend was launched with:
[...]apparently it picked up a wrong UID. On the QNAP:
[...]but TVHeadend interpreted "admin" with UID 1 (and GID 1). I don't know why.
As you can recall from the logs, this behaviour happens only on the NAS with 64-bit kernel.

So running TVHeadend without the "-u" and "-g" switches picked up UID 0 and now the user reports that it's working correctly (and tuning). Is this a bug?
I'm available if you have additional tests to do.

Ok, so we're close. TVH uses standard getgrnam() and getpwnam() functions: https://github.com/tvheadend/tvheadend/blob/master/src/main.c#L712-L745

As you can see, the 1 values are when these functions return NULL. It looks like a glibc issue... Perhaps, the /etc path is prefixed for compilation ? Maybe strace might show which files are read at runtime.

By the way, I was trying to compile the latest version (as I was still running 3.9-2496-gd386ed0) and it fails with:
[...]Can you fix it too?

v3.9-2659-g1f79d9d fixes it..

virtual dj wrote:

v3.9-2659-g1f79d9d fixes it..

Thanks, it compiles perfectly now.

As you can see, the 1 values are when these functions return NULL.

Yes, I've tried adding a tvhdebug statement on the "else" part of grp and pw: both of them are NULL.

It looks like a glibc issue... Perhaps, the /etc path is prefixed for compilation ?

Sorry, I miss the "/etc" prefix thing. What does it mean? I do not use prefixes (you can see how I compile on the first post of this ticket) nor /etc is in my PATH.

I meant the /etc location - something like "--sysconfdir=" when you configure glibc. Maybe, you picked binaries from other location - maybe you missed some .so binaries (/lib/libnss*?).

Maybe strace might show which files are read at runtime.

The strace result is attached. Let me know if I have to do it in a different way.
I wasn't able to mix the strace output with the TVHeadend log, anyway I hit CTRL+C when I saw the line:
[...]

Unfortunately, I don't see any open() calls for the /etc tree there. It seems a bit malformed. There should be line like:

open("/etc/passwd", O_RDONLY|O_CLOEXEC) = 3

I meant the /etc location - something like "--sysconfdir=" when you configure glibc. Maybe, you picked binaries from other location - maybe you missed some .so binaries (/lib/libnss*?).

Actually I didn't configure glibc at all. I just copied the Debian squeeze binaries from the VM (only those reported by ldd tvheadend) on the QNAP and run the application from there using ld-linux-....

I've tried copying libnss too as you said, but it doesn't change anything (I don't think it picks them up at all, even if it's in the LD_LIBRARY_PATH).

Also "libc/ld-linux-x86-64.so.2 --list" reports that all the libraries are correctly loaded from the path where I've copied the files.

Unfortunately, I don't see any open() calls for the /etc tree there. It seems a bit malformed.

I do not see them too.

strace -e open,access libc/ld-linux-x86-64.so.2 --library-path /share/Public/mytest/libc ./tvheadend -d -u admin -g administrators -C

open(0xc0384b63, O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 030016027320) = 0
open("libssl.so.0.9.8", O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 030016026060) = 0
open("libcrypto.so.0.9.8", O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 030016026000) = 0
open("libz.so.1", O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 030016025720) = 0
open("libdl.so.2", O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 030016025640) = 0
open("libpthread.so.0", O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 030016025560) = 0
open("libm.so.6", O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 030016025500) = 0
open("librt.so.1", O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 030016025420) = 0
open("libc.so.6", O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 030016025340) = 0
open(0xc0382630, O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 02300320100) = 0
open(0x142fd020, O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 030016023260) = 0
open(0x142fced0, O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 030016023260) = 0
open(0x3, O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 030016022600) = 0
open(0x142fd600, O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 030016024140) = 0
open(0x142fd600, O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 030016023420) = 0
open(0x142fe3e0, O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 030016023400) = 0
open(0xc0382840, O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 030016017440) = 0
open(0x3, O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 030016016060) = 0
open(0x3, O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 030016017320) = 0
open("/root/.hts/tvheadend/.lock", O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 030016021640) = 0
2015-03-28 11:03:47.840 [   INFO] main: Log started
2015-03-28 11:03:48.159 [WARNING] START: configuration path /root/.hts/tvheadend is not r/w for UID:1 GID:1 [e=Permission denied], settings will not be saved
2015-03-28 11:03:48.160 [  ALERT] settings: Unable to create dir "/root/.hts/tvheadend": Permission denied
2015-03-28 11:03:48.160 [  ALERT] settings: Unable to create dir "/root/.hts/tvheadend": Permission denied
2015-03-28 11:03:48.160 [  ALERT] settings: Unable to create dir "/root/.hts/tvheadend": Permission denied
2015-03-28 11:03:48.161 [   INFO] bouquet: new bouquet 'Canal Digitaal SD'
2015-03-28 11:03:48.161 [  ALERT] settings: Unable to create dir "/root/.hts/tvheadend": Permission denied
2015-03-28 11:03:48.161 [   INFO] bouquet: new bouquet 'Canal Digitaal HD'
2015-03-28 11:03:48.161 [  ALERT] settings: Unable to create dir "/root/.hts/tvheadend": Permission denied
2015-03-28 11:03:48.161 [   INFO] bouquet: new bouquet 'TV Vlaanderen SD'
2015-03-28 11:03:48.161 [  ALERT] settings: Unable to create dir "/root/.hts/tvheadend": Permission denied
... cut ...
2015-03-28 11:03:48.372 [   INFO] scanfile: DVB-T - loaded 43 regions with 729 networks
2015-03-28 11:03:48.373 [   INFO] scanfile: DVB-S - loaded 1 regions with 93 networks
2015-03-28 11:03:48.373 [   INFO] scanfile: DVB-C - loaded 16 regions with 51 networks
2015-03-28 11:03:48.373 [   INFO] scanfile: ATSC - loaded 2 regions with 14 networks
2015-03-28 11:03:48.373 [  DEBUG] fsmonitor: watch /dev
2015-03-28 11:03:48.373 [   INFO] dvr: Creating new configuration ''
2015-03-28 11:03:48.373 [  ALERT] settings: Unable to create dir "/root/.hts/tvheadend": Permission denied
2015-03-28 11:03:48.373 [WARNING] dvr: Output directory for video recording is not yet configured for DVR configuration "". Defaulting to to "/root". This can be changed from the web user interface.
2015-03-28 11:03:48.373 [  ALERT] settings: Unable to create dir "/root/.hts/tvheadend": Permission denied
2015-03-28 11:03:48.373 [  ALERT] settings: Unable to create dir "/root/.hts/tvheadend": Permission denied
2015-03-28 11:03:48.373 [WARNING] access: Created default wide open access controle entry
2015-03-28 11:03:48.374 [   INFO] CSA: Using SSE2 128bit parallel descrambling
... cut ...
2015-03-28 11:03:48.382 [  DEBUG] epgdb: database does not exist
2015-03-28 11:03:48.382 [ NOTICE] START: HTS Tvheadend version 3.9.2660~g169b71b-dirty started, running as PID:1783 UID:1 GID:1, CWD:/share/CACHEDEV1_DATA/Public/mytest CNF:/root/.hts/tvheadend
--- SIGABRT (Aborted) @ 0 (0) ---
--- SIGABRT (Aborted) @ 0 (0) ---
+++ killed by SIGABRT +++
Aborted

I made another test; please pardon me if it's totally wrong I just want to help you (I'm not a programmer and I only used Google).
I compiled the following program in the Debian VM (the same used to compile TVHeadend):

root@debian-x64:~/tvheadend/tvheadend# cat utest.c 

#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>

int main(int argc, char *argv[])
{
        uid_t id = getuid();
        printf("Current UID = %d\n", id); 
        return 0;
}

[/share/Public/mytest] # ./a.out 
Current UID = 0
[/share/Public/mytest] # libc/ld-linux-x86-64.so.2 --library-path /share/Public/mytest/libc ./a.out 
Current UID = 0
[/share/Public/mytest] # su guest
[/share/Public/mytest] # ./a.out 
Current UID = 65534
[/share/Public/mytest] # exit
exit

[/share/Public/mytest] # strace -e open,access ./a.out 
open(0x3, O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 07071523140) = 0
open("libc.so.6", O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 07071523260) = 0
open(0x26066780, O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 07071523260) = 0
Current UID = 0

[/share/Public/mytest] # strace -e open,access libc/ld-linux-x86-64.so.2 --library-path /share/Public/mytest/libc ./a.out 
open(0x5b0ebb88, O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 013303512460) = 0
open("libc.so.6", O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 013303511220) = 0
open(0x99062780, O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 013303511260) = 0
Current UID = 0

You should test getgrnam() and getpwnam() functions, not getuid() - for getuid() the /etc files are not accessed, becauase this information is obtained from kernel using syscalls.

You should test getgrnam() and getpwnam() functions, not getuid() - for getuid() the /etc files are not accessed, becauase this information is obtained from kernel using syscalls.

Thanks for the explanation, I've updated the a.out binary with the following source code:

root@debian-x64:~/tvheadend/tvheadend# cat utest.c

#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
#include <pwd.h>

int main(int argc, char *argv[])
{
        struct passwd *user;

        if ((user= getpwnam(argv[1])) == NULL)
                printf("User not found.\n");
        else
                printf("User %s ID = %d.\n", user->pw_name, user->pw_uid);
        return 0;
}

root@debian-x64:~/tvheadend/tvheadend# strace -e open ./a.out root
open("/etc/ld.so.cache", O_RDONLY)      = 3
open("/lib/libc.so.6", O_RDONLY)        = 3
open("/etc/nsswitch.conf", O_RDONLY)    = 3
open("/etc/ld.so.cache", O_RDONLY)      = 3
open("/lib/libnss_compat.so.2", O_RDONLY) = 3
open("/lib/libnsl.so.1", O_RDONLY)      = 3
open("/etc/ld.so.cache", O_RDONLY)      = 3
open("/lib/libnss_nis.so.2", O_RDONLY)  = 3
open("/lib/libnss_files.so.2", O_RDONLY) = 3
open("/etc/passwd", O_RDONLY|O_CLOEXEC) = 3
User root ID = 0.
root@debian-x64:~/tvheadend/tvheadend# strace -e open ./a.out web
open("/etc/ld.so.cache", O_RDONLY)      = 3
open("/lib/libc.so.6", O_RDONLY)        = 3
open("/etc/nsswitch.conf", O_RDONLY)    = 3
open("/etc/ld.so.cache", O_RDONLY)      = 3
open("/lib/libnss_compat.so.2", O_RDONLY) = 3
open("/lib/libnsl.so.1", O_RDONLY)      = 3
open("/etc/ld.so.cache", O_RDONLY)      = 3
open("/lib/libnss_nis.so.2", O_RDONLY)  = 3
open("/lib/libnss_files.so.2", O_RDONLY) = 3
open("/etc/passwd", O_RDONLY|O_CLOEXEC) = 3
User web ID = 1000.

[/share/Public/mytest] # strace -e open libc/ld-linux-x86-64.so.2 --library-path /share/Public/mytest/libc ./a.out admin
open(0xeaa24b96, O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 035250434320) = 0
open("libc.so.6", O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 035250433060) = 0
open(0xfa36b420, O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 035250436140) = 0
open(0xeaa23da0, O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 035250432200) = 0
open(0x3, O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 035250430620) = 0
open(0x3, O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 035250432060) = 0
open(0xfa143780, O_ACCMODE|O_CREAT|O_EXCL|O_NOCTTY|O_TRUNC|O_APPEND|O_NONBLOCK|O_SYNC|O_ASYNC|O_DIRECT|O_LARGEFILE|O_DIRECTORY|O_NOFOLLOW|O_NOATIME|0xfff8003c, 035250436700) = 0
User not found.

[/share/Public/mytest] # ls libc/
ld-linux-x86-64.so.2*     libnss_dns-2.11.3.so      libnss_nis.so.2
libc.so.6*                libnss_dns.so.2           libnss_nisplus-2.11.3.so
libcrypto.so.0.9.8        libnss_files-2.11.3.so    libnss_nisplus.so.2
libdl.so.2                libnss_files.so.2         libpthread.so.0*
libm.so.6                 libnss_hesiod-2.11.3.so   librt.so.1
libnss_compat-2.11.3.so   libnss_hesiod.so.2        libssl.so.0.9.8
libnss_compat.so.2        libnss_nis-2.11.3.so      libz.so.1

Aha, I think I've found the problem myself... It was libnsl.so.1 that was missing.

[/share/Public/mytest] # ls libc/
ld-linux-x86-64.so.2* libm.so.6             librt.so.1
libc.so.6*            libnsl.so.1           libssl.so.0.9.8
libcrypto.so.0.9.8    libnss_compat.so.2    libz.so.1
libdl.so.2            libpthread.so.0*

[/share/Public/mytest] # libc/ld-linux-x86-64.so.2 --library-path /share/Public/mytest/libc ./a.out admin
User admin ID = 0.

[/share/Public/mytest] # libc/ld-linux-x86-64.so.2 --library-path /share/Public/mytest/libc ./tvheadend -d -u admin -g administrators -C
2015-03-28 21:24:04.538 [   INFO] main: Log started
2015-03-28 21:24:04.556 [  DEBUG] config: no configuration, loading defaults
2015-03-28 21:24:04.596 [  DEBUG] settings: saving to /share/CACHEDEV1_DATA/homes/admin/.hts/tvheadend/config
2015-03-28 21:24:04.596 [   INFO] config: loaded
2015-03-28 21:24:04.597 [  DEBUG] settings: saving to /share/CACHEDEV1_DATA/homes/admin/.hts/tvheadend/profile/6eefe2c679eabb03252b98094b224e38
2015-03-28 21:24:04.597 [  DEBUG] settings: saving to /share/CACHEDEV1_DATA/homes/admin/.hts/tvheadend/profile/3195b8bde7e6394c9542a6eb42e4db7c
2015-03-28 21:24:04.597 [  DEBUG] settings: saving to /share/CACHEDEV1_DATA/homes/admin/.hts/tvheadend/profile/1caaf0095f58eded731f62076ec1dcce
2015-03-28 21:24:04.598 [   INFO] bouquet: new bouquet 'Canal Digitaal SD'
2015-03-28 21:24:04.598 [  DEBUG] settings: saving to /share/CACHEDEV1_DATA/homes/admin/.hts/tvheadend/bouquet/dd04a1b29a3e247f73597897393a0289
... cut ...
2015-03-28 21:24:04.601 [  DEBUG] settings: saving to /share/CACHEDEV1_DATA/homes/admin/.hts/tvheadend/bouquet/b860a0c6c5e0d7edcbbaf05fa00c2120
2015-03-28 21:24:04.806 [   INFO] scanfile: DVB-T - loaded 43 regions with 729 networks
2015-03-28 21:24:04.806 [   INFO] scanfile: DVB-S - loaded 1 regions with 93 networks
2015-03-28 21:24:04.806 [   INFO] scanfile: DVB-C - loaded 16 regions with 51 networks
2015-03-28 21:24:04.806 [   INFO] scanfile: ATSC - loaded 2 regions with 14 networks
2015-03-28 21:24:04.807 [  DEBUG] fsmonitor: watch /dev
2015-03-28 21:24:04.807 [   INFO] dvr: Creating new configuration ''
2015-03-28 21:24:04.807 [  DEBUG] settings: saving to /share/CACHEDEV1_DATA/homes/admin/.hts/tvheadend/dvr/config/b678ae36e35780443c22a3fc9658f179
2015-03-28 21:24:04.807 [WARNING] dvr: Output directory for video recording is not yet configured for DVR configuration "". Defaulting to to "/share/homes/admin". This can be changed from the web user interface.
2015-03-28 21:24:04.807 [  DEBUG] settings: saving to /share/CACHEDEV1_DATA/homes/admin/.hts/tvheadend/accesscontrol/4d445e48c5e13117f07bd3ea6fcc934b
2015-03-28 21:24:04.808 [  DEBUG] settings: saving to /share/CACHEDEV1_DATA/homes/admin/.hts/tvheadend/accesscontrol/4d445e48c5e13117f07bd3ea6fcc934b
2015-03-28 21:24:04.863 [WARNING] access: Created default wide open access controle entry
2015-03-28 21:24:04.863 [   INFO] CSA: Using SSE2 128bit parallel descrambling
2015-03-28 21:24:04.863 [   INFO] epggrab: module eit created
... cut ...
2015-03-28 21:24:04.871 [  DEBUG] epggrab: using internal grab search
2015-03-28 21:24:04.871 [  DEBUG] epgdb: database does not exist
2015-03-28 21:24:04.872 [  DEBUG] settings: saving to /share/CACHEDEV1_DATA/homes/admin/.hts/tvheadend/config
2015-03-28 21:24:04.872 [ NOTICE] START: HTS Tvheadend version 3.9.2660~g169b71b-dirty started, running as PID:10179 UID:0 GID:0, CWD:/share/CACHEDEV1_DATA/Public/mytest CNF:/share/CACHEDEV1_DATA/homes/admin/.hts/tvheadend
Aborted