Address OpenSSL initialization issues when using third-party libraries.

When Asterisk is used with various third-party libraries (CURL, PostgresSQL,
many others) that have the ability themselves to use OpenSSL, it is possible
for conflicts to arise in how the OpenSSL libraries are initialized and
shutdown. This patch addresses these conflicts by 'wrapping' the important
functions from the OpenSSL libraries in a new shared library that is part
of Asterisk itself, and is loaded in such a way as to ensure that *all*
calls to these functions will be dispatched through the Asterisk wrapper
functions, not the native functions.

This new library is optional, but enabled by default. See the CHANGES file
for documentation on how to disable it.

Along the way, this patch also makes a few other minor changes:

* Changes MODULES_DIR to ASTMODDIR throughout the build system, in order to
  more closely match what is used during run-time configuration.

* Corrects some errors in the configure script where AC_CHECK_TOOLS was used
  instead of AC_PATH_PROG.

* Adds a new variable for linker flags in the build system (DYLINK), used for
  producing true shared libraries (as opposed to the dynamically loadable
  modules that the build system produces for 'regular' Asterisk modules).

* Moves the Makefile bits that handle installation and uninstallation of the
  main Asterisk binary into main/Makefile from the top-level Makefile.

* Moves a couple of useful preprocessor macros from optional_api.h to
  asterisk.h.

Review: https://reviewboard.asterisk.org/r/1006/


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@353317 65c4cc65-6c06-0410-ace0-fbb531ad65f3

configure.ac

@@ -47,7 +47,8 @@ AC_USE_SYSTEM_EXTENSIONS	dnl note- does not work on FreeBSD
 AC_SUBST([astsbindir],        ['${sbindir}'])dnl
 AC_SUBST([astetcdir],         ['${sysconfdir}/asterisk'])dnl
 AC_SUBST([astheaderdir],      ['${includedir}/asterisk'])dnl
-AC_SUBST([astlibdir],         ['${libdir}/asterisk'])dnl
+AC_SUBST([astlibdir],         ['${libdir}'])dnl
+AC_SUBST([astmoddir],         ['${libdir}/asterisk/modules'])dnl
 AC_SUBST([astmandir],         ['${mandir}'])dnl
 AC_SUBST([astvarlibdir],      ['${localstatedir}/lib/asterisk'])dnl
 AC_SUBST([astdatadir],        ['${astvarlibdir}'])dnl
@@ -93,7 +94,7 @@ case "${host_os}" in
      darwin*)
      ac_default_prefix=/usr/local
      if test ${prefix} = 'NONE'; then
-        astlibdir='/Library/Application Support/Asterisk/Modules'
+        astmoddir='/Library/Application Support/Asterisk/Modules'
         astvarlibdir='/Library/Application Support/Asterisk'
         astlogdir=/Library/Logs/Asterisk
         astvarrundir='/Library/Application Support/Asterisk/Run'
@@ -106,6 +107,7 @@ case "${host_os}" in
         astetcdir=/var/etc/asterisk
         astsbindir=/opt/asterisk/sbin
         astlibdir=/opt/asterisk/lib
+        astmoddir=/opt/asterisk/lib/modules
         astheaderdir=/opt/asterisk/include
         astmandir=/opt/asterisk/man
         astvarlibdir=/var/opt/asterisk
@@ -210,7 +212,7 @@ AH_BOTTOM(
 )
 
 # cross-compile checks
-if test "${cross_compiling}" = "yes"; 
+if test "${cross_compiling}" = "yes";
 then
    AC_CHECK_TOOL(CC, gcc, :)
    AC_CHECK_TOOL(CXX, g++, :)
@@ -234,8 +236,6 @@ AC_PROG_EGREP
 
 AC_CHECK_TOOLS([STRIP], [strip gstrip], :)
 AC_CHECK_TOOLS([AR], [ar gar], :)
-AC_CHECK_TOOLS([SHA1SUM], [sha1sum], $ac_aux_dir/build_tools/sha1sum-sh)
-AC_CHECK_TOOLS([OPENSSL], [openssl], :)
 
 GNU_LD=0
 if test "x$with_gnu_ld" = "xyes" ; then
@@ -271,6 +271,9 @@ else
 fi
 fi
 AC_SUBST(DOWNLOAD)
+AC_PATH_PROG([LDCONFIG], [ldconfig], :)
+AC_PATH_PROG([SHA1SUM], [sha1sum], $ac_aux_dir/build_tools/sha1sum-sh)
+AC_PATH_PROG([OPENSSL], [openssl], :)
 
 AC_CACHE_CHECK([for bison that supports parse-param], [ac_cv_path_BISON2], [
 	if test "x$BISON" != "x:" ; then
@@ -323,7 +326,7 @@ fi
 AC_CHECK_PROGS([MD5], [md5 md5sum gmd5sum digest])
 
 if test "${MD5}" = "digest" ; then
-   MD5="${MD5} -a md5"   
+   MD5="${MD5} -a md5"
 fi
 
 ACX_PTHREAD
@@ -498,7 +501,7 @@ AC_SUBST(EDITLINE_LIB)
 # Another mandatory item (unless it's explicitly disabled)
 AC_ARG_ENABLE([xmldoc],
 	[AS_HELP_STRING([--disable-xmldoc],
-		[Explicity disable XML documentation])],
+		[Explicitly disable XML documentation])],
 	[case "${enableval}" in
 		y|ye|yes) disable_xmldoc=no ;;
 		n|no)  disable_xmldoc=yes ;;
@@ -622,7 +625,7 @@ AC_SUBST(PBX_DYNAMIC_LIST)
 LDFLAGS=${old_LDFLAGS}
 rm -f conftest.dynamics
 
-AC_CHECK_HEADER([sys/poll.h], 
+AC_CHECK_HEADER([sys/poll.h],
    [HAS_POLL=1]
    AC_DEFINE([HAVE_SYS_POLL_H], 1, [Define to 1 if your system has working sys/poll.h]),
    )
@@ -637,7 +640,15 @@ AC_ARG_ENABLE([internal-poll],
 	esac])
 AC_SUBST(HAS_POLL)
 
-
+AC_ARG_ENABLE([asteriskssl],
+	[AS_HELP_STRING([--disable-asteriskssl],
+		[Disable Asterisk's SSL wrapper library])],
+	[case "${enableval}" in
+		y|ye|yes) AST_ASTERISKSSL=yes ;;
+		n|no)  AST_ASTERISKSSL=no ;;
+		*) AC_MSG_ERROR(bad value ${enableval} for --disable-asteriskssl)  ;;
+	esac], [AST_ASTERISKSSL=yes])
+AC_SUBST(AST_ASTERISKSSL)
 
 # https support (in main/http.c) uses funopen on BSD systems,
 # fopencookie on linux
@@ -1482,7 +1493,7 @@ if test "${USE_IMAP_TK}" != "no"; then
 				fi
 			fi
 		fi
-	fi 
+	fi
 	if test "${IMAP_TK_DIR}" = "system"; then
 		#We will enter here if user specified "system" or if any of above checks failed
 		AC_MSG_CHECKING([for system c-client library...])
@@ -1740,7 +1751,7 @@ if test "${USE_IMAP_TK}" != "no"; then
 			AC_DEFINE([HAVE_IMAP_TK2006], 1, [Define if your system has the UW IMAP Toolkit c-client library version 2006 or greater.])
 		fi
 	else
-		AC_MSG_RESULT(no) 
+		AC_MSG_RESULT(no)
 	fi
 	CPPFLAGS="${saved_cppflags}"
 	LIBS="${saved_libs}"
@@ -1811,7 +1822,7 @@ AST_EXT_LIB_CHECK([OSS], [ossaudio], [], [sys/soundcard.h])
 AST_EXT_LIB_CHECK([OSS], [ossaudio], [oss_ioctl_mixer], [soundcard.h])
 
 PG_CONFIG=No
-if test "${USE_PGSQL}" != "no"; then	
+if test "${USE_PGSQL}" != "no"; then
    if test "x${PGSQL_DIR}" != "x"; then
       AC_PATH_TOOL([PG_CONFIG], [pg_config], No, [${PGSQL_DIR}/bin])
       if test x"${PG_CONFIG}" = xNo; then
@@ -1837,7 +1848,7 @@ if test "${PG_CONFIG}" != No; then
          AC_MSG_NOTICE([*** including --without-postgres])
          exit 1
 	  fi
-   else 
+   else
       AC_CHECK_LIB([pq], [PQescapeStringConn], AC_DEFINE_UNQUOTED([HAVE_PGSQL], 1,
       [Define to indicate the PostgreSQL library]), [], -L${PGSQL_libdir} -lz)
 
@@ -1930,7 +1941,7 @@ if test "${USE_PWLIB}" != "no"; then
 	fi
 	AST_CHECK_PWLIB()
 	AST_CHECK_PWLIB_VERSION([PWLib], [PWLIB], [ptbuildopts.h], [1], [9], [2], [P[[WT]]LIB_VERSION])
-		
+
 	if test "${HAS_PWLIB:-unset}" != "unset"; then
 		AST_CHECK_PWLIB_PLATFORM()
 
@@ -1960,7 +1971,7 @@ if test "${PBX_PWLIB}" = "1" -a "${USE_OPENH323}" != "no" ; then
 		[${PWLIB_INCLUDE}], [${PWLIB_LIB}])
 fi
 
-AST_EXT_LIB_CHECK([LUA], [lua5.1], [luaL_newstate], [lua5.1/lua.h], [-lm]) 
+AST_EXT_LIB_CHECK([LUA], [lua5.1], [luaL_newstate], [lua5.1/lua.h], [-lm])
 if test "x${PBX_LUA}" = "x1" ; then
 	if test x"${LUA_DIR}" = x; then
 		LUA_INCLUDE="${LUA_INCLUDE} -I/usr/include/lua5.1"
@@ -1968,9 +1979,9 @@ if test "x${PBX_LUA}" = "x1" ; then
 		LUA_INCLUDE="${LUA_INCLUDE} -I${LUA_DIR}/lua5.1"
 	fi
 fi
-	
+
 # Some distributions (like SuSE) remove the 5.1 suffix.
-AST_EXT_LIB_CHECK([LUA], [lua], [luaL_register], [lua.h], [-lm]) 
+AST_EXT_LIB_CHECK([LUA], [lua], [luaL_register], [lua.h], [-lm])
 
 AST_EXT_LIB_CHECK([RADIUS], [radiusclient-ng], [rc_read_config], [radiusclient-ng.h])
 
@@ -2136,11 +2147,11 @@ if test "${USE_VPB}" != "no"; then
 	[#include <vpbapi.h>],
 	[int q = vpb_open(0,0);])
 	],
-	[	AC_MSG_RESULT(yes) 
-		ac_cv_lib_vpb_vpb_open="yes" 
+	[	AC_MSG_RESULT(yes)
+		ac_cv_lib_vpb_vpb_open="yes"
 	],
-	[	AC_MSG_RESULT(no) 
-		ac_cv_lib_vpb_vpb_open="no" 
+	[	AC_MSG_RESULT(no)
+		ac_cv_lib_vpb_vpb_open="no"
 	]
 	)
    LIBS="${saved_libs}"
@@ -2322,8 +2333,8 @@ fi
 AC_MSG_NOTICE(Package configured for: )
 AC_MSG_NOTICE( OS type  : $host_os)
 AC_MSG_NOTICE( Host CPU : $host_cpu)
-AC_MSG_NOTICE( build-cpu:vendor:os: $build_cpu : $build_vendor : $build_os :) 
-AC_MSG_NOTICE( host-cpu:vendor:os: $host_cpu : $host_vendor : $host_os :) 
+AC_MSG_NOTICE( build-cpu:vendor:os: $build_cpu : $build_vendor : $build_os :)
+AC_MSG_NOTICE( host-cpu:vendor:os: $host_cpu : $host_vendor : $host_os :)
 if test "${cross_compiling}" = "yes"; then
    AC_MSG_NOTICE( Cross Compilation = YES)
 fi