From 9d92ed4dc4d6d691668609641043561137e91401 Mon Sep 17 00:00:00 2001
From: Sutou Kouhei <kou@clear-code.com>
Date: Fri, 30 Jun 2023 09:41:52 +0900
Subject: [PATCH] GH-36329: [C++][CI] Use OpenSSL 3 on macOS (#36336)

### Rationale for this change

GitHub Actions self-hosted runner for macOS has
/usr/local/include/openssl/ provided by OpenSSL 3 (`openssl@ 3`). Our include paths have `... -isystem /usr/local/include -isystem /usr/local/opt/openssl@ 1.1/include ...`. It means that `/usr/local/include/openssl/...` is used for `#include <openssl/...>`.

If we mix OpenSSL 3 headers and OpenSSL 1.1 libraries, we may get some problems such as a link error.

### What changes are included in this PR?

This uses OpenSSL 3 instead of OpenSSL 1.1 because GitHub Actions self-hosted runner for macOS provides OpenSSL 3 by /usr/local/include/openssl/. Note that `$(brew --prefix openssl@ 3)/include` isn't linked as /usr/local/include/openssl` by default. So I think that Homebrew GitHub Actions self-hosted runner for macOS does it explicitly.

Other solution: Unlinking `/usr/local/include/openssl` by `brew unlink openssl@ 3`. But there is no reason to use OpenSSL 1.1 for us. So this PR doesn't use this solution.

### Are these changes tested?

Yes.

### Are there any user-facing changes?

Yes.
* Closes: #36329

Authored-by: Sutou Kouhei <kou@clear-code.com>
Signed-off-by: Sutou Kouhei <kou@clear-code.com>
---
 cpp/Brewfile                           |  2 +-
 cpp/cmake_modules/FindOpenSSLAlt.cmake | 22 +++++++++++-----------
 2 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/cpp/Brewfile b/cpp/Brewfile
index 66f1bd332bbf9..580e8d3f115d5 100644
--- a/cpp/Brewfile
+++ b/cpp/Brewfile
@@ -30,7 +30,7 @@ brew "grpc"
 brew "llvm@14"
 brew "lz4"
 brew "ninja"
-brew "openssl@1.1"
+brew "openssl@3"
 brew "protobuf"
 brew "python"
 brew "rapidjson"
diff --git a/cpp/cmake_modules/FindOpenSSLAlt.cmake b/cpp/cmake_modules/FindOpenSSLAlt.cmake
index f027eb1026dde..03c61e6ea2ad5 100644
--- a/cpp/cmake_modules/FindOpenSSLAlt.cmake
+++ b/cpp/cmake_modules/FindOpenSSLAlt.cmake
@@ -22,19 +22,19 @@ endif()
 if(APPLE AND NOT OPENSSL_ROOT_DIR)
   find_program(BREW brew)
   if(BREW)
-    execute_process(COMMAND ${BREW} --prefix "openssl@1.1"
-                    OUTPUT_VARIABLE OPENSSL11_BREW_PREFIX
-                    OUTPUT_STRIP_TRAILING_WHITESPACE)
-    if(OPENSSL11_BREW_PREFIX)
-      set(OPENSSL_ROOT_DIR ${OPENSSL11_BREW_PREFIX})
-    else()
-      execute_process(COMMAND ${BREW} --prefix "openssl"
-                      OUTPUT_VARIABLE OPENSSL_BREW_PREFIX
+    foreach(BREW_OPENSSL_VERSION "" "3" "3.0" "1.1")
+      set(BREW_OPENSSL_PACKAGE "openssl")
+      if(BREW_OPENSSL_VERSION)
+        string(APPEND BREW_OPENSSL_PACKAGE "@${BREW_OPENSSL_VERSION}")
+      endif()
+      execute_process(COMMAND ${BREW} --prefix --installed ${BREW_OPENSSL_PACKAGE}
+                      OUTPUT_VARIABLE BREW_OPENSSL_PREFIX
                       OUTPUT_STRIP_TRAILING_WHITESPACE)
-      if(OPENSSL_BREW_PREFIX)
-        set(OPENSSL_ROOT_DIR ${OPENSSL_BREW_PREFIX})
+      if(BREW_OPENSSL_PREFIX)
+        set(OPENSSL_ROOT_DIR ${BREW_OPENSSL_PREFIX})
+        break()
       endif()
-    endif()
+    endforeach()
   endif()
 endif()