From 2713842400042841a8b89c02091356f9ffa24dd9 Mon Sep 17 00:00:00 2001
From: Henri Menke <henri@henrimenke.de>
Date: Thu, 2 Jul 2026 09:42:21 +0200
Subject: [PATCH] Avoid path doubling issue in CMake files
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There is no guarantee that `CMAKE_INSTALL_LIBDIR` (and for that matter
`LWS_INSTALL_LIBDIR`) are relative paths, so that it would be safe to concatenate
it with `CMAKE_INSTALL_PREFIX`. If `CMAKE_INSTALL_LIBDIR` is set to an absolute
path, e.g. `/usr/lib` and `CMAKE_INSTALL_PREFIX` is set to `/usr` this leads to
path doubling in various places where there now appears `/usr/usr/lib`.

Here we use the “full” variants of those variables instead which branch
correctly on both absolute and relative paths.
---
 cmake/lws_config.h.in | 2 +-
 lib/CMakeLists.txt    | 8 ++++----
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/cmake/lws_config.h.in b/cmake/lws_config.h.in
index d06c38c7c..8e0ce81bf 100644
--- a/cmake/lws_config.h.in
+++ b/cmake/lws_config.h.in
@@ -7,7 +7,7 @@
 #endif
 
 #define LWS_INSTALL_DATADIR "${CMAKE_INSTALL_PREFIX}/share"
-#define LWS_INSTALL_LIBDIR "${CMAKE_INSTALL_PREFIX}/${LWS_INSTALL_LIB_DIR}"
+#define LWS_INSTALL_LIBDIR "${CMAKE_INSTALL_FULL_LIBDIR}"
 #define LWS_PLUGIN_DIR "${LWS_INSTALL_PLUGIN_DIR}"
 #define LWS_LIBRARY_VERSION_MAJOR ${LWS_LIBRARY_VERSION_MAJOR}
 #define LWS_LIBRARY_VERSION_MINOR ${LWS_LIBRARY_VERSION_MINOR}
diff --git a/lib/CMakeLists.txt b/lib/CMakeLists.txt
index fedb0ed95..d30c2b07e 100644
--- a/lib/CMakeLists.txt
+++ b/lib/CMakeLists.txt
@@ -429,8 +429,8 @@ endif()
 file(WRITE "${PROJECT_BINARY_DIR}/libwebsockets.pc"
 "prefix=\"${CMAKE_INSTALL_PREFIX}\"
 exec_prefix=\${prefix}
-libdir=\${exec_prefix}/${LWS_INSTALL_LIB_DIR}
-includedir=\${prefix}/${LWS_INSTALL_INCLUDE_DIR}
+libdir=${CMAKE_INSTALL_FULL_LIBDIR}
+includedir=${CMAKE_INSTALL_FULL_INCLUDEDIR}
 
 Name: libwebsockets
 Description: Websockets server and client library
@@ -451,8 +451,8 @@ endif()
 file(WRITE "${PROJECT_BINARY_DIR}/libwebsockets_static.pc"
 "prefix=\"${CMAKE_INSTALL_PREFIX}\"
 exec_prefix=\${prefix}
-libdir=\${exec_prefix}/${LWS_INSTALL_LIB_DIR}
-includedir=\${prefix}/${LWS_INSTALL_INCLUDE_DIR}
+libdir=${CMAKE_INSTALL_FULL_LIBDIR}
+includedir=${CMAKE_INSTALL_FULL_INCLUDEDIR}
 
 Name: libwebsockets_static
 Description: Websockets server and client static library