Need to include signal.h to define pthread_kill() and SIGURG.

Change-Id: I10ae3aa4bf8e7386ac29ade78c0f2caed8e674fa

res_pjsip_registrar_expire remains as an empty module for now.

Change-Id: Ib93698938bae548d2199cb542f3692d1a171239f

The sample modules.conf explicitly loaded res_musiconhold.so.  This is
redundent as autoload=yes is already set.  It causes warnings if
res_musiconhold.so was not installed and results in an unexpected load
if the admin disables autoload without remembering to remove the
res_musiconhold load statement.

Also remove reference to unknown module pbx_gtkconsole.

Change-Id: Ib01888994d9f1364b14d3c9fb6ff96774a6e580a

deleted
 automake git ncurses-devel pjproject-devel sqlite2-devel libsqlite3x-devel

renamed
 radiusclient-ng-devel to radcli-devel
 gmime22-devel to gmime-dev

added
 alsa-lib-devel bash binutils-devel bison doxygen flex hoard make pkgconfig
 speexdsp-devel uriparser-devel uw-imap-devel wget xmlstarlet zlib-devel
 codec2-devel fftw-devel libsndfile-devel unbound-devel

ASTERISK-27599
Reported by: Said Masoud

Change-Id: I05bb0af98ae532b2d5f37478e38b8f0762b1c035

Because of a copy-and-paste from the script build_tools/download_externals,
the script build_tools/list_valid_installed_externals got its local variables.
However in the latter, three variables were not used actually.

Change-Id: I252de5a98c17ea54459174875357c22c2eebe8d5

This addresses all performance issues with 'module load' completion.  In
addition to using ast_cli_completion_add we stop using libedit's
filename_completion_function, instead using ast_file_read_dir.  This
ensures all results are produced from a single call to opendir.

Change-Id: I8bf51ffaa7ef1606f3bd1b5bb13f1905d72c6134

The previous fix broke the case
HAVE_SYSINFO = no
HAVE_SYSCTL = yes
HAVE_SWAPCTL = no
which occurs on FreeBSD 11.1 for example.

ASTERISK-26563

Change-Id: If77c39bc75f0b83a6c8a24ecb2fa69be8846160a

clang 4.0 warned about this.

ASTERISK-27630

Change-Id: Ie2725048c661c1792d8b1d498575144350b6e9ba

Because of a copy-and-paste error, the Asterisk project was using __typeof
instead of typeof. It works because typeof, __typeof, and __typeof__ are
supported by GCC, but here the escaped variant was not intended. Therefore,
for consistence, we change this to typeof.

Change-Id: I2a962c3e596e882f691a19345445b14571a5f07c

ASTERISK-16172

Change-Id: I2fb564258cd4db0f35952ad48b8687355c2dcad3

ASTERISK-27603

Change-Id: I65c587534c0ae364f063d68da1bed40bb3d5e8aa

Move initialization of units which do not require configuration to occur
before preload modules.  This leaves only units which load config between
module preload and regular load stages.

Change-Id: I1d15384acad16a22c3498124421af474fa517478

This change causes the configure script to throw an error if neither
__sync nor __atomic builtin functions are available.

ASTERISK-27619

Change-Id: Ie01a281e0f5c41dfeeb5f250c1ccea8752f56ef9

The code which handled loading modules had too many situations which
would result in halting Asterisk startup.  Treat most errors as declines
instead of failures.  The exception is when the module load function
returns AST_MODULE_LOAD_FAILURE or an invalid code.

Clear the missingdeps vector when appropriate to ensure the next loop
starts clean.

ASTERISK-27620

Change-Id: I45547d9641fd45bd86d80250224417625631ad84

Add a check to configure.ac for __atomic_fetch_add support.  If found
use the __atomic built-in operators for ast_atomic_dec_and_test and
ast_atomic_fetchadd_int.

ASTERISK~27619

Change-Id: I65b4feb02bae368904ed0fb03f585c05f50a690e

This removes references that are no longer needed due to automatic
references created by module dependencies.

In addition this removes most calls to ast_module_check as they were
checking modules which are listed as dependencies.

Change-Id: I332a6e8383d4c72c8e89d988a184ab8320c4872e

ASTERISK-27581

Change-Id: If6af275764741a11030f0a4fd324fa29b376d74e