From 2914950c4407b90b7f253d0ceb01e34d4a06d977 Mon Sep 17 00:00:00 2001
From: Sam Clark <3758302+goatgoose@users.noreply.github.com>
Date: Sat, 29 Jul 2023 21:34:24 -0400
Subject: [PATCH] traditional make

---
 docs/BUILD.md | 40 +++++++++++++++++++++++++++++++---------
 1 file changed, 31 insertions(+), 9 deletions(-)

diff --git a/docs/BUILD.md b/docs/BUILD.md
index b8e678154f2..836421ab4e9 100644
--- a/docs/BUILD.md
+++ b/docs/BUILD.md
@@ -28,14 +28,11 @@ brew install cmake ninja go
 # MacOS does not have a supported libcrypto preinstalled, but OpenSSL can be installed with brew
 brew install openssl@3
 
-# get the libcrypto install directory
-openssl_dir=$(dirname $(dirname $(brew list openssl@3|grep libcrypto.dylib)))
-
 # build s2n-tls
 cmake . -Bbuild -GNinja \
-    -DCMAKE_PREFIX_PATH=$openssl_dir
-ninja -C build
-ninja -C build test
+    -DCMAKE_PREFIX_PATH=$(dirname $(dirname $(brew list openssl@3|grep libcrypto.dylib)))
+ninja -C build -j $(sysctl -n hw.ncpu)
+CTEST_PARALLEL_LEVEL=$(sysctl -n hw.ncpu) ninja -C build test
 ```
 </details>
 
@@ -46,14 +43,14 @@ ninja -C build test
 ```
 </details>
 
-s2n-tls can be configured with the following cmake options. Each option can be configured by passing a `-D<option>=<value>` flag to cmake.
+s2n-tls can be configured with the following CMake options. Each option can be configured by passing a `-D<option>=<value>` flag to CMake.
 - [**`CMAKE_INSTALL_PREFIX`**](https://cmake.org/cmake/help/latest/variable/CMAKE_INSTALL_PREFIX.html): Specifies where the s2n-tls library and binary artifacts are placed when installing s2n-tls via `ninja -C build install`.
-- [**`CMAKE_PREFIX_PATH`**](https://cmake.org/cmake/help/latest/variable/CMAKE_PREFIX_PATH.html): Specifies install locations used by cmake to search for library dependencies. This option can be used to link s2n-tls to a specific libcrypto. See the [Using a specific libcrypto](#using-a-specific-libcrypto) section for more information on building with different libcryptos.
+- [**`CMAKE_PREFIX_PATH`**](https://cmake.org/cmake/help/latest/variable/CMAKE_PREFIX_PATH.html): Specifies install locations used by CMake to search for library dependencies. This option can be used to link s2n-tls to a specific libcrypto. See the [Using a specific libcrypto](#using-a-specific-libcrypto) section for more information on building with different libcryptos.
 - [**`CMAKE_BUILD_TYPE`**](https://cmake.org/cmake/help/latest/variable/CMAKE_BUILD_TYPE.html): Sets the build type. Some of the possible build types are as follows:
   - `Release`: Produce an optimized s2n-tls library artifact with no debug info. This option should be used when building s2n-tls for use in production.
   - `Debug`: Produce an unoptimized library artifact with debug info. This option can be used when developing for or with s2n-tls. The debug symbols produced with this build can be used with GDB or to generate more informative stack traces.
 
-The entire list of s2n-tls cmake options can be viewed with `cmake . -LH`. 
+The entire list of s2n-tls CMake options can be viewed with `cmake . -LH`. 
 
 ## Building with a specific libcrypto
 
@@ -103,3 +100,28 @@ ninja -C build install
 </details>
 
 For more information on building AWS-LC, see the [Building AWS-LC documentation](https://github.com/aws/aws-lc/blob/main/BUILDING.md)
+
+## Other build methods
+
+### Non-ninja CMake
+
+s2n-tls can be built via CMake without a dependency on Ninja:
+
+<details open>
+<summary>Ubuntu</summary>
+
+```
+cmake . -Bbuild \
+    -DCMAKE_PREFIX_PATH=$(dirname $(dirname $(brew list openssl@3|grep libcrypto.dylib)))
+cmake --build build -j $(sysctl -n hw.ncpu)
+CTEST_PARALLEL_LEVEL=$(sysctl -n hw.ncpu) ctest --test-dir build
+```
+</details>
+
+### Traditional make
+
+CMake is the preferred s2n-tls build system, and includes updated build features and supports the most platforms. However, building s2n-tls with a traditional Makefile is also supported. With make, the desired libcrypto install path must be set with the `LIBCRYPTO_ROOT` environment variable.
+
+```
+LIBCRYPTO_ROOT=/usr/local/ssl make
+```