CMake: backport CMake buildsystem from master to release/2.6

This is based on the initial CMake patch by
Arne Schwabe, but extends that to provide
a complete replacement for existing MinGW
build (autotools based) and MSVC build
(openvpn.sln).

The following features are added while switching
these builds to CMake:
 - vcpkg support for MinGW build, allowing for
   trivial cross-compilation on Linux
 - Add unittests to MSVC build
 - Rework MSVC config header generation, removing
   need for separate headers between autotools
   and MSVC

The following advantages are reasons for switching
to CMake over the existing MSVC build:
 - Easier to maintain CMake files without IDE
   than the sln and vcxproj files
 - Able to maintain MSVC and MinGW build side-by-side

The plan is to completely remove the existing MSVC
build system but leave the existing autotools builds
in place as-is, including MinGW support.

CMake is not the intended build system for Unix-like
platforms and there are no current plans to switch
to it.

This commits squashes a lot of commits from master
together, since most of them are just fixes or
enhancements for the original CMake commit. The
decisions was not to bloat the release/2.6 commit
history with these detours.

It contains the following commits:
- add basic CMake based build
  (commit 0134184012dd46ec44cbca7eb3ece39037ae0bfa by
   Arne Schwabe)
- CMake: Add complete MinGW and MSVC build
  (commit e8881ec6dd63bd80ce05202573eac54ab8657fcb)
- CMake: Add /Brepro to MSVC link options
  (commit 5e94e8de4bfaf6637124947a3489710b591e5e26)
- Do not blindly assume python3 is also the interpreter that runs rst2html
  (commit 5dbec1c019d14880ae7bf364b062d3589c7fd9e7 by
   Arne Schwabe)
- Only add -Wno-stringop-truncation on supported compilers
  (commit eb3cd5ea36f9bf235da7b8a51fd6ce29780f0e39 by
   Arne Schwabe)
- CMake: Throw a clear error when config.h in top-level source directory
  (commit 0652ae84f4528daa57da344eee28b7385a6659a1)
- openvpnmsica: link C runtime statically
  (commit 3be4986ea3d6e27acd3e3a317c15dfe07688e135 by
   Lev Stipakov)
- CMake: Support doc builds on Windows machines that do not have .py file association
  (commit 22213a8834ba5ba5c9818015730edbf3766ad915)
- README.cmake.md: Add new documentation for CMake buildsystem
  (commit 53055fd23efb6209b12d3662427158e25247f1fe)
- Check if the -wrap argument is actually supported by the platform's ld
  (commit 4ef76f0ee4e122dcd616e1b1e2d652562ab10756 by
   Arne Schwabe)
- GHA: update to run-vcpkg@v11
  (commit 66e33ee81d1d7fa3495ae3aad6e673766e296687)
- GHA: refactor mingw UTs and add missing tls_crypt
  (commit 26c663f12815f55c483dbe660e28448dc63221d1)
- CMake: various small non-functional improvements
  (commit 95cc5faa16833acaf12a4d273c5c848984fc73ce)
- CMake: fix broken daemonization and syslog functionality
  (commit 8ae6c48d5d52dec8ec6e47cc1cfe89de9f2ffbcd)
- CMake: fix HAVE_DAEMON detection on Linux
  (commit e363b393f2d1b72590666554e17d928c1603f8d5)

Change-Id: I6de18261d5dc7f8561612184059656c73f33a5f2
Signed-off-by: Frank Lichtenheld <frank@lichtenheld.com>
Acked-by: Lev Stipakov <lstipakov@gmail.com>
Co-authored-by: Arne Schwabe <arne@rfc2549.org>
Co-authored-by: Lev Stipakov <lev@openvpn.net>
Message-Id: <20230926095030.29779-1-frank@lichtenheld.com>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg27107.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>

2 files changed, 33 insertions, 0 deletions

diff --git a/contrib/vcpkg-manifests/mingw/vcpkg.json b/contrib/vcpkg-manifests/mingw/vcpkg.json
new file mode 100644
index 0000000..fc00b01
--- /dev/null
+++ b/contrib/vcpkg-manifests/mingw/vcpkg.json
@@ -0,0 +1,13 @@
+{
+  "$schema": "https://raw.githubusercontent.com/microsoft/vcpkg/master/scripts/vcpkg.schema.json",
+  "name": "openvpn",
+  "version": "2.7",
+  "dependencies": [
+      "openssl",
+      "tap-windows6",
+      "lzo",
+      "lz4",
+      "pkcs11-helper",
+      "cmocka"
+  ]
+}
diff --git a/contrib/vcpkg-manifests/windows/vcpkg.json b/contrib/vcpkg-manifests/windows/vcpkg.json
new file mode 100644
index 0000000..67a1f87
--- /dev/null
+++ b/contrib/vcpkg-manifests/windows/vcpkg.json
@@ -0,0 +1,20 @@
+{
+  "$schema": "https://raw.githubusercontent.com/microsoft/vcpkg/master/scripts/vcpkg.schema.json",
+  "name": "openvpn",
+  "version": "2.7",
+  "dependencies": [
+      {
+        "name": "openssl",
+        "features": ["tools"]
+      },
+      "tap-windows6",
+      "lzo",
+      "lz4",
+      "pkcs11-helper",
+      "cmocka",
+      {
+          "name": "pkgconf",
+          "host": true
+      }
+  ]
+}