Added Windows build instructions

Author: Martin Köditz

README.md

@@ -26,5 +26,83 @@ $ Don't forget to run 'make test'.
 ```
 You can find the `interbase.so` file in directory `php-firebird/modules`. Copy the file to your php extension dir and restart your webserver.
 
-## Clean up your working directory
+#### Clean up your working directory
 After you've created the binary data, many temporary files will be created in your working directory. These can be removed with the command `phpize --clean`. Then you have a tidy directory again.
+
+### Build the driver on Windows
+First of all, we have to meet some requirements. This means we need to install the Git for Windows and Visual Studio 2017 with following components:
+Visual C++ 2017 (vc15) or Visual C++ 2019 (vc16) must be installed prior SDK usage. Required components
+- C++ dev
+- Windows SDK
+- .NET dev
+
+Also make sure you are using a 64-bit build host with Windows 7 or later.
+Of course we need some Firebird related stuff. The easiest way is to install the related Firebird version on your build host including the development files.
+
+To start the build process open a command line. We assume that the build is done in the directory `c:\php-sdk`. So make sure you have the permission to create that folder on Drive C:.
+```
+git clone https://github.com/Microsoft/php-sdk-binary-tools.git c:\php-sdk
+cd c:\php-sdk
+git checkout php-sdk-2.2.0
+```
+With the above we downloaded the PHP SDK and entered our working directory. 
+
+Next we will prepare our build environment.
+For Win32 do:
+```
+phpsdk-vc15-x86.bat
+```
+Use following command for Win64:
+```
+phpsdk-vc15-x64.bat
+```
+If you use VS 2019, replace vc15 by vc16.
+
+Now let's create the build structure, download the PHP sources and checkout the desired development branch:
+```
+phpsdk_buildtree phpmaster
+git clone https://github.com/php/php-src.git && cd php-src && git checkout PHP-7.4.0
+```
+
+Since we have our PHP sources now, we're on to get the depending libraries.
+```
+phpsdk_deps --update --branch 7.4
+```
+
+In the next step we will download our Firebird extension sources.
+```
+mkdir ..\pecl
+git clone https://github.com/FirebirdSQL/php-firebird.git ..\pecl\interbase
+```
+
+If everything is ok, we can now compile our PHP extension. Please specify the the correct path to your Firebird installation.
+
+#### Build TS extension
+Usually you will build thread safe extensions.
+For Win32 thread safe (TS) do:
+```
+buildconf && configure --enable-cli --with-interbase="shared,C:\Program Files (x86)\Firebird\3_0" && nmake
+```
+For Win64thread safe (TS) do:
+```
+buildconf && configure --enable-cli --with-interbase="shared,C:\Program Files\Firebird\3_0" && nmake
+```
+After the compilation you can find your extension called `php_interbase.dll` e.g. in `C:\php-sdk\phpmaster\vc15\x64\php-src\x64\Release_TS\php_interbase.dll`
+Replace x64 with x86 for Win32.
+
+#### Build NTS extension
+For Win32 non-thread safe (NTS) run:
+```
+buildconf && configure --disable-zts --enable-cli --with-interbase="shared,C:\Program Files (x86)\Firebird\3_0" && nmake
+```
+For Win64 non-thread safe (NTS) run:
+```
+buildconf && configure --disable-zts --enable-cli --with-interbase="shared,C:\Program Files\Firebird\3_0" && nmake
+```
+After the compilation you can find your extension called `php_interbase.dll` e.g. in `C:\php-sdk\phpmaster\vc15\x86\php-src\Release`
+Replace x86 with x64 for Win64.
+
+
+
+
+