Add CMake build file

This can potentially replace the visual studio build files.

These can now be generated with e.g.:

  cmake . -G "Visual Studio 15"

Or for 64 bit:

  cmake . -G "Visual Studio 15 2017 Win64"

Also updated readme to reflect this.

.gitignore

@@ -23,6 +23,7 @@ old?
 *.app
 
 # srtp things
+build
 Debug
 Makefile
 Root

CMakeLists.txt

@@ -0,0 +1,89 @@
+cmake_minimum_required (VERSION 2.8)
+
+project(srtp2)
+
+set(SOURCES_C
+	srtp/ekt.c
+	srtp/srtp.c
+)
+
+set(CIPHERS_SOURCES_C
+	crypto/cipher/aes.c
+	crypto/cipher/aes_icm.c
+	crypto/cipher/cipher.c
+	crypto/cipher/null_cipher.c
+)
+
+set(HASHES_SOURCES_C
+	crypto/hash/auth.c
+	crypto/hash/hmac.c
+	crypto/hash/null_auth.c
+	crypto/hash/sha1.c
+)
+
+set(KERNEL_SOURCES_C
+	crypto/kernel/alloc.c
+	crypto/kernel/crypto_kernel.c
+	crypto/kernel/err.c
+	crypto/kernel/key.c
+)
+
+set(MATH_SOURCES_C
+	crypto/math/datatypes.c
+	crypto/math/stat.c
+)
+
+set(REPLAY_SOURCES_C
+	crypto/replay/rdb.c
+	crypto/replay/rdbx.c
+	crypto/replay/ut_sim.c
+)
+
+set(SOURCES_H
+	crypto/include/aes.h
+	crypto/include/aes_icm.h
+	crypto/include/alloc.h
+	crypto/include/auth.h
+	crypto/include/cipher.h
+	crypto/include/cipher_types.h
+	crypto/include/config.h
+	crypto/include/crypto_kernel.h
+	crypto/include/crypto_types.h
+	crypto/include/datatypes.h
+	crypto/include/err.h
+	crypto/include/hmac.h
+	crypto/include/integers.h
+	crypto/include/key.h
+	crypto/include/null_auth.h
+	crypto/include/null_cipher.h
+	crypto/include/rdb.h
+	crypto/include/rdbx.h
+	crypto/include/sha1.h
+	crypto/include/stat.h
+	include/ekt.h
+	include/srtp.h
+	include/srtp_priv.h
+	include/ut_sim.h
+)
+
+source_group("src" FILES ${SOURCES_C})
+source_group("src\\Ciphers" FILES ${CIPHERS_SOURCES_C})
+source_group("src\\Hashes" FILES ${HASHES_SOURCES_C})
+source_group("src\\Kernel" FILES ${KERNEL_SOURCES_C})
+source_group("src\\Math" FILES ${MATH_SOURCES_C})
+source_group("src\\Replay" FILES ${REPLAY_SOURCES_C})
+source_group("include" FILES ${SOURCES_H})
+
+add_library(srtp2 STATIC
+	${SOURCES_C}
+	${CIPHERS_SOURCES_C}
+	${HASHES_SOURCES_C}
+	${KERNEL_SOURCES_C}
+	${MATH_SOURCES_C}
+	${REPLAY_SOURCES_C}
+	${SOURCES_H}
+)
+
+target_include_directories(srtp2 PUBLIC crypto/include include)
+configure_file(config.hw ${CMAKE_CURRENT_SOURCE_DIR}/crypto/include/config.h COPYONLY)
+add_definitions(-D_LIB -DHAVE_CONFIG_H)

README.md

@@ -31,7 +31,7 @@ because it does its work behind the scenes.
 
 --------------------------------------------------------------------------------
 
-<a name="contact"></a>
+<a name="contact-us"></a>
 # Contact Us
 
 - [libsrtp@lists.packetizer.com](mailto:libsrtp@lists.packetizer.com) general mailing list for news / announcements / discussions. This is an open list, see
@@ -46,7 +46,7 @@ because it does its work behind the scenes.
 ## Contents
 
 - [Introduction to libSRTP](#introduction-to-libsrtp)
-  - [Contact Us](#contact)
+- [Contact Us](#contact-us)
   - [Contents](#contents)
 - [License and Disclaimer](#license-and-disclaimer)
 - [libSRTP Overview](#libsrtp-overview)
@@ -55,6 +55,7 @@ because it does its work behind the scenes.
   - [Implementation Notes](#implementation-notes)
 - [Installing and Building libSRTP](#installing-and-building-libsrtp)
   - [Changing Build Configuration](#changing-build-configuration)
+  - [Using Visual Studio](#using-visual-studio)
 - [Applications](#applications)
   - [Example Code](#example-code)
 - [Credits](#credits)
@@ -313,6 +314,26 @@ brew install automake pkgconfig
 autoremake -ivf
 ```
 
+--------------------------------------------------------------------------------
+<a name="using-visual-studio"></a>
+## Using Visual Studio
+
+On Windows one can use Visual Studio via CMake. CMake can be downloaded here:
+https://cmake.org/ . To create Visual Studio build files, for example run the
+following commands:
+
+```
+# Create build subdirectory
+mkdir build
+cd build
+
+# Make project files
+cmake .. -G "Visual Studio 15 2017"
+
+# Or for 64 bit project files
+cmake .. -G "Visual Studio 15 2017 Win64"
+```
+
 --------------------------------------------------------------------------------
 
 <a name="applications"></a>