This check puts all of our code in a C++ anonymous namespace, which is
effectively making all functions `static`. This allows the compiler to
determine that a function is unused, so we can delete it.
It is invalid to compile an XPG3, XPG4, XPG4v2, or XPG5 application
using c99. The same is true for POSIX.1-1990, POSIX.2-1992, POSIX.1b,
and POSIX.1c applications. Likewise, it is invalid to compile an XPG6
or a POSIX.1-2001 application with anything other than a c99 or later
compiler. Therefore, Solaris libc forces an error in both cases.
Reduced by, e.g.:
* `file_transfer_test`: 33% of the `clock_gettime` calls.
* `tox_many_test`: 53% of the `clock_gettime` calls.
Other tests will see similar improvements. Real world applications will
be closer to 40-50% improvement, since tox_many_test has 100 nodes, while
file_transfer_test has 2 nodes.
It turns out, `unix_time` is also monotonic, and is used as such, so I've
renamed the new functions to `mono_time_*`.
2018-07-08:
```
00:01 <@irungentoo> the idea used to be that the unix_time() function
could go backward in time but I think I might have started using it like
if it could not after I changed it so that it would never go back in time
```
Rules:
1. Constants are uppercase names: THE_CONSTANT.
2. SUE[1] types start with an uppercase letter and have at least one
lowercase letter in it: The_Type, THE_Type.
3. Function types end in "_cb": tox_friend_connection_cb.
4. Variable and function names are all lowercase: the_function.
This makes it easier for humans reading the code to determine what an
identifier means. I'm not convinced by the enum type name change, but I
don't know a better rule. Currently, a lot of enum types are spelled like
constants, which is confusing.
[1] struct/union/enum
These display some idea, but the tests are not implemented correctly. We
will need to implement the idea correctly later, but for now we can't use
these.
This change does not include the addition of VP9. We do that in a
separate pull request.
Changes:
* fix the video bug (video frames larger than 65KBytes) by sending full
frame length in alternate header field
* improve video frame reconstruction logic with slots
* configure video encoder and decoder to be multihtreaded
* set error resilience flags on video codec
* change encoder and decoder softdeadline
