From 9c4faae381aa0d725528c069aa4fea909134de28 Mon Sep 17 00:00:00 2001
From: Mario Fetka <mario.fetka@gmail.com>
Date: Wed, 3 Jun 2026 11:23:17 +0000
Subject: [PATCH] Rewrite prefixed libowfat exported header includes

---
 CMakeLists.txt | 33 ++++++++++++++++++++++++++-------
 README.md      | 15 +++++++++++++++
 2 files changed, 41 insertions(+), 7 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index fa79b16..2740593 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -85,10 +85,29 @@ set(_generated_dir "${CMAKE_CURRENT_BINARY_DIR}/generated")
 set(_generated_libowfat_dir "${_generated_dir}/libowfat")
 file(MAKE_DIRECTORY "${_generated_libowfat_dir}" "${LIBOWFAT_BUILD_PUBLIC_INCLUDE_DIR}")
 
+function(_libowfat_rewrite_public_includes out_var content)
+  set(_rewritten "${content}")
+  if(NOT LIBOWFAT_INSTALL_INCLUDE_SUBDIR STREQUAL "libowfat")
+    string(REPLACE "<libowfat/" "<${LIBOWFAT_INSTALL_INCLUDE_SUBDIR}/" _rewritten "${_rewritten}")
+    string(REPLACE "\"libowfat/" "\"${LIBOWFAT_INSTALL_INCLUDE_SUBDIR}/" _rewritten "${_rewritten}")
+  endif()
+  set(${out_var} "${_rewritten}" PARENT_SCOPE)
+endfunction()
+
+function(_write_public_header name content)
+  _libowfat_rewrite_public_includes(_public_content "${content}")
+  file(WRITE "${LIBOWFAT_BUILD_PUBLIC_INCLUDE_DIR}/${name}" "${_public_content}")
+endfunction()
+
 function(_write_generated_header name content)
   file(WRITE "${_generated_dir}/${name}" "${content}")
   file(WRITE "${_generated_libowfat_dir}/${name}" "${content}")
-  file(WRITE "${LIBOWFAT_BUILD_PUBLIC_INCLUDE_DIR}/${name}" "${content}")
+  _write_public_header("${name}" "${content}")
+endfunction()
+
+function(_copy_public_header input name)
+  file(READ "${input}" _header_content)
+  _write_public_header("${name}" "${_header_content}")
 endfunction()
 
 function(_write_feature_header name content_if_true)
@@ -137,20 +156,20 @@ _write_generated_header(havealloca.h "${_havealloca_content}")
 if(HAVE_POLL)
   configure_file("${CMAKE_CURRENT_SOURCE_DIR}/iopause.h2" "${_generated_dir}/iopause.h" COPYONLY)
   configure_file("${CMAKE_CURRENT_SOURCE_DIR}/iopause.h2" "${_generated_libowfat_dir}/iopause.h" COPYONLY)
-  configure_file("${CMAKE_CURRENT_SOURCE_DIR}/iopause.h2" "${LIBOWFAT_BUILD_PUBLIC_INCLUDE_DIR}/iopause.h" COPYONLY)
+  _copy_public_header("${CMAKE_CURRENT_SOURCE_DIR}/iopause.h2" iopause.h)
 else()
   configure_file("${CMAKE_CURRENT_SOURCE_DIR}/iopause.h1" "${_generated_dir}/iopause.h" COPYONLY)
   configure_file("${CMAKE_CURRENT_SOURCE_DIR}/iopause.h1" "${_generated_libowfat_dir}/iopause.h" COPYONLY)
-  configure_file("${CMAKE_CURRENT_SOURCE_DIR}/iopause.h1" "${LIBOWFAT_BUILD_PUBLIC_INCLUDE_DIR}/iopause.h" COPYONLY)
+  _copy_public_header("${CMAKE_CURRENT_SOURCE_DIR}/iopause.h1" iopause.h)
 endif()
 if(HAVE_SYS_SELECT_H)
   configure_file("${CMAKE_CURRENT_SOURCE_DIR}/select.h2" "${_generated_dir}/select.h" COPYONLY)
   configure_file("${CMAKE_CURRENT_SOURCE_DIR}/select.h2" "${_generated_libowfat_dir}/select.h" COPYONLY)
-  configure_file("${CMAKE_CURRENT_SOURCE_DIR}/select.h2" "${LIBOWFAT_BUILD_PUBLIC_INCLUDE_DIR}/select.h" COPYONLY)
+  _copy_public_header("${CMAKE_CURRENT_SOURCE_DIR}/select.h2" select.h)
 else()
   configure_file("${CMAKE_CURRENT_SOURCE_DIR}/select.h1" "${_generated_dir}/select.h" COPYONLY)
   configure_file("${CMAKE_CURRENT_SOURCE_DIR}/select.h1" "${_generated_libowfat_dir}/select.h" COPYONLY)
-  configure_file("${CMAKE_CURRENT_SOURCE_DIR}/select.h1" "${LIBOWFAT_BUILD_PUBLIC_INCLUDE_DIR}/select.h" COPYONLY)
+  _copy_public_header("${CMAKE_CURRENT_SOURCE_DIR}/select.h1" select.h)
 endif()
 
 add_executable(libowfat_ent EXCLUDE_FROM_ALL "${CMAKE_CURRENT_SOURCE_DIR}/ent.c")
@@ -182,10 +201,10 @@ set(LIBOWFAT_PUBLIC_HEADERS
 foreach(_hdr IN LISTS LIBOWFAT_PUBLIC_HEADERS)
   if(EXISTS "${_generated_dir}/${_hdr}")
     configure_file("${_generated_dir}/${_hdr}" "${_generated_libowfat_dir}/${_hdr}" COPYONLY)
-    configure_file("${_generated_dir}/${_hdr}" "${LIBOWFAT_BUILD_PUBLIC_INCLUDE_DIR}/${_hdr}" COPYONLY)
+    _copy_public_header("${_generated_dir}/${_hdr}" "${_hdr}")
   else()
     configure_file("${CMAKE_CURRENT_SOURCE_DIR}/${_hdr}" "${_generated_libowfat_dir}/${_hdr}" COPYONLY)
-    configure_file("${CMAKE_CURRENT_SOURCE_DIR}/${_hdr}" "${LIBOWFAT_BUILD_PUBLIC_INCLUDE_DIR}/${_hdr}" COPYONLY)
+    _copy_public_header("${CMAKE_CURRENT_SOURCE_DIR}/${_hdr}" "${_hdr}")
   endif()
 endforeach()
 
diff --git a/README.md b/README.md
index 8f860c0..451eddc 100644
--- a/README.md
+++ b/README.md
@@ -109,3 +109,18 @@ be enabled explicitly:
 -DLIBOWFAT_BUILD_TEST_PROGRAMS=ON
 -DLIBOWFAT_RUN_SELF_TESTS=ON
 ```
+
+### Prefixed CMake header exports
+
+When `LIBOWFAT_LIBRARY_PREFIX` is set, CMake exports public headers below a
+matching include directory, for example `nwlibowfat`. The original sources and
+internal build include tree still keep the upstream `libowfat` layout, but the
+public build/install header copies are rewritten so their nested includes also
+use the selected directory name. For example:
+
+```c
+#include <nwlibowfat/buffer.h>
+```
+
+will include other libowfat headers through `nwlibowfat/...`, avoiding conflicts
+with a system-installed `libowfat` header set.