Clean up GnuTLS linking and instructions

GnuTLS can have different crypto backends, and it is rarely gcrypt
these days. So we should not be including that unconditionally,
and should not be pointing people at it either. Also remove the
section about Win32 binaries as those are out of date and probably
insecure. Lastly remove the section about static builds as it is
a general issue and in no way complete with just the GnuTLS portions.

1 files changed, 1 insertions, 82 deletions

diff --git a/BUILDING.txt b/BUILDING.txt
index 897a51a3..4ffcb726 100644
--- a/BUILDING.txt
+++ b/BUILDING.txt
@@ -14,7 +14,7 @@ Build Requirements (All Systems)
    * See "Building FLTK" below.
 
 -- If building TLS support:
-   * GnuTLS and its dependencies (libgcrypt, libtasn1, libgpg-error)
+   * GnuTLS
 
 -- If building native language support (NLS):
    * Gnu gettext 0.14.4 or later
@@ -390,87 +390,6 @@ to the CMake command line would link TigerVNC against the static versions of
 libiconv and libintl included in the MinGW Developer Toolkit.
 
 
-===============================================
-Building Transport Layer Security (TLS) support
-===============================================
-
-VeNCrypt (the TigerVNC security and authentication extensions) can be built
-with TLS support, which provides built-in encryption for VNC sessions.  This
-requires GnuTLS, which is readily available in many Linux distributions but not
-as readily available in binary form on other types of systems.  This section
-describes the issues associated with building a version of TigerVNC with TLS
-support and how to work around those issues.
-
-
-Unix/Mac
---------
-
-In general, if you are building on a Unix-ish platform that has the GnuTLS
-libraries and include files installed in the standard system locations, then
-the TigerVNC build system should detect the system version of GnuTLS
-automatically and link against it.  However, this produces a version of
-TigerVNC that depends on the GnuTLS dynamic libraries, and thus the TigerVNC
-binaries are not portable.
-
-To build a fully portable, cross-compatible version of TigerVNC with TLS
-support, it is necessary to link against the GnuTLS static library (as well
-as the static libraries of its dependencies.)  If you are lucky enough, then
-your O/S distribution may include pre-packaged versions of these static
-libraries.  Otherwise, it will be necessary to build GnuTLS, libgcrypt,
-libtasn1, and libgpg-error from source.
-
-You can manipulate the GNUTLS_INCLUDE_DIR and GNUTLS_LIBRARY CMake variables to
-build TigerVNC against a custom build of GnuTLS that is installed in a
-non-system directory.  For instance, adding
-
-  -DGNUTLS_INCLUDE_DIR=/opt/gnutls/include \
-    -DGNUTLS_LIBRARY='/opt/gnutls/lib/libgnutls.a;/opt/gnutls/lib/libgcrypt.a;/opt/gnutls/lib/libgpg-error.a;/opt/gnutls/lib/libtasn1.a' \
-    -DUSE_INCLUDED_ZLIB=1
-
-to the CMake or 'build-xorg build' command line will cause TigerVNC to be
-statically linked against a custom installation of GnuTLS that resides under
-/opt/gnutls.  GnuTLS depends on zlib, so specifying -DUSE_INCLUDED_ZLIB=1 will
-satisfy that dependency using TigerVNC's in-tree version of zlib, which
-prevents TigerVNC from depending on the libz dynamic library.
-
-
-MinGW
------
-
-An installer containing the GnuTLS header files, as well as static and dynamic
-link libraries for 32-bit MinGW, can be downloaded from the following site:
-
-http://josefsson.org/gnutls4win/
-
-As of this writing, GnuTLS cannot be built cleanly with MinGW64 due to the fact
-that portions of the code assume an LP64 data model (Windows uses LLP64.)
-Thus, it is not possible at this time to produce a Win64 version of TigerVNC
-with TLS support.
-
-Whether you use the above installer or build GnuTLS from source, make sure that
-you install the libraries and headers into a pathname that doesn't contain
-spaces (the installer will try to install under c:\Program Files unless you
-tell it otherwise.)  If the GnuTLS include path contains spaces, then the MinGW
-resource compiler will barf when you try to build TigerVNC.
-
-You can manipulate the GNUTLS_INCLUDE_DIR and GNUTLS_LIBRARY CMake variables to
-specify the directory under which you installed GnuTLS.  For instance, adding
-
-  -DGNUTLS_INCLUDE_DIR=/c/gnutls/include \
-    -DGNUTLS_LIBRARY=/c/gnutls/lib/libgnutls.dll.a
-
-to the CMake command line when using MinGW will cause TigerVNC to be linked
-against GnuTLS DLLs that are installed under c:\gnutls.
-
-Adding
-
-  -DGNUTLS_INCLUDE_DIR=/c/gnutls/include \
-    -DGNUTLS_LIBRARY='/c/gnutls/lib/libgnutls.a;/c/gnutls/lib/libgcrypt.a;/c/gnutls/lib/libtasn1.a;/c/gnutls/lib/libgpg-error.a'
-
-to the CMake command line will cause TigerVNC to be statically linked against
-GnuTLS libraries that are installed under c:\gnutls.
-
-
 ===================
 Installing TigerVNC
 ===================