Merged revisions 282200-282201 via svnmerge from

https://origsvn.digium.com/svn/asterisk/branches/1.8

........
  r282200 | twilson | 2010-08-13 11:00:02 -0500 (Fri, 13 Aug 2010) | 10 lines
  
  Detect when libsrtp cannot be linked in a shared library
  
  The libsrtp build system currently does not produce a shared library
  or a static library compiled with -fPIC, so on 64-bit systems it is
  possible that we will get a compile error if libsrtp is installed and
  res_srtp is selected in menuselect.
  
  This patch attempts to detect this situation and provide the user with
  instructions to work around the problem.
........
  r282201 | twilson | 2010-08-13 11:02:20 -0500 (Fri, 13 Aug 2010) | 2 lines
  
  Whitespace fix :-/
........


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@282202 65c4cc65-6c06-0410-ace0-fbb531ad65f3

configure.ac

@@ -1807,6 +1807,38 @@ fi
 
 AST_EXT_LIB_CHECK([SRTP], [srtp], [srtp_init], [srtp/srtp.h])
 
+if test "$PBX_SRTP" = "1";
+then
+    saved_libs="${LIBS}"
+    saved_ldflags="${LDFLAGS}"
+    LIBS="${LIBS} -lsrtp"
+    LDFLAGS="${LDFLAGS} -shared -fPIC"
+    AC_MSG_CHECKING(for the ability of -lsrtp to be linked in a shared object)
+    AC_LINK_IFELSE(
+    [
+        AC_LANG_PROGRAM(
+            [#include <srtp/srtp.h>],
+            [srtp_init();]
+        )
+    ],
+    [ AC_MSG_RESULT(yes) ],
+    [
+        AC_MSG_RESULT(no)
+        AC_MSG_NOTICE(***)
+        AC_MSG_NOTICE(*** libsrtp could not be linked as a shared object)
+        AC_MSG_NOTICE(*** try compiling libsrtp manually and configuring with)
+        AC_MSG_NOTICE(*** ./configure CFLAGS=-fPIC --prefix=/usr)
+        AC_MSG_NOTICE(*** replacing /usr with the prefix of your choice)
+        AC_MSG_NOTICE(***)
+        AC_MSG_NOTICE(*** If you do not need SRTP support re-run configure)
+        AC_MSG_NOTICE(*** with the --without-srtp option.)
+        exit 1
+    ]
+    )
+    LIBS="${saved_libs}"
+    LDFLAGS="${saved_ldflags}"
+fi
+
 AST_EXT_TOOL_CHECK([GMIME], [gmime-config], [], [], [#include <gmime/gmime.h>], [gboolean q = g_mime_check_version(0,0,0);])
 
 AST_EXT_LIB_CHECK([HOARD], [hoard], [malloc], [])