From 4aa8cf8c93e1fa6ffeb40fc3473f32b1b83af141 Mon Sep 17 00:00:00 2001
From: "Ilya A. Kriveshko" <iillyyaa@gmail.com>
Date: Tue, 2 Jan 2024 15:37:10 -0500
Subject: [PATCH] cmake: respect explicit install prefix

If CMAKE_INSTALL_PREFIX was supplied externally, use it.  This follows
the pattern suggested by cmake documentation in:
https://cmake.org/cmake/help/latest/variable/CMAKE_INSTALL_PREFIX_INITIALIZED_TO_DEFAULT.html

Upstream-status: Submitted [https://github.com/sierrafoxtrot/srecord/pull/68]
---
 CMakeLists.txt | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 74b8108c..ac9f464e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -30,9 +30,9 @@ include(InstallRequiredSystemLibraries)
 include(GNUInstallDirs)
 
 # FHS compliant paths for Linux installation
-if(NOT WIN32 AND CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
-#  set(CMAKE_INSTALL_PREFIX "/opt/${PROJECT_NAME}")
-  set(CMAKE_INSTALL_PREFIX "/usr")
+if(CMAKE_INSTALL_PREFIX_INITIALIZED_TO_DEFAULT
+        AND NOT WIN32 AND CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
+  set(CMAKE_INSTALL_PREFIX "/usr" CACHE PATH "Install prefix" FORCE)
 endif()
 
 # Pull in the rest of the pieces