Fix error introduced in 1275a3f91a by
using signed 32 bit integer which is enough for Frame Number in
GSM. Also, mark parameter constraints more explicitly:
- add assert for expected FN values
- don't perform computation for non-relative FN
The error was:
bts.cpp: In member function ‘uint32_t BTS::rfn_to_fn(uint32_t)’:
bts.cpp:554:25: error: call of overloaded ‘abs(uint32_t)’ is ambiguous
if (abs(rfn - m_cur_rfn) > RFN_THRESHOLD) {
^
In file included from /usr/include/c++/6/cstdlib:75:0,
from /usr/include/c++/6/stdlib.h:36,
from /usr/include/osmocom/core/linuxrbtree.h:97,
from /usr/include/osmocom/core/timer.h:35,
from ./bts.h:29,
from bts.cpp:21:
/usr/include/stdlib.h:735:12: note: candidate: int abs(int)
extern int abs (int __x) __THROW __attribute__ ((__const__)) __wur;
^~~
In file included from /usr/include/c++/6/stdlib.h:36:0,
from /usr/include/osmocom/core/linuxrbtree.h:97,
from /usr/include/osmocom/core/timer.h:35,
from ./bts.h:29,
from bts.cpp:21:
/usr/include/c++/6/cstdlib:185:3: note: candidate: __int128 std::abs(__int128)
abs(__GLIBCXX_TYPE_INT_N_0 __x) { return __x >= 0 ? __x : -__x; }
^~~
/usr/include/c++/6/cstdlib:180:3: note: candidate: long long int std::abs(long long int)
abs(long long __x) { return __builtin_llabs (__x); }
^~~
/usr/include/c++/6/cstdlib:172:3: note: candidate: long int std::abs(long int)
abs(long __i) { return __builtin_labs(__i); }
Change-Id: Ib6d895a97aa35414f245ea4406c6e78f1b4fb5b8