From 344e73e000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: David Woodhouse <dwmw2@infradead.org>
Date: Fri, 31 Oct 2026 10:31:00 +0000
Subject: [PATCH] libwebem: fall back to pkg-config to find jsoncpp

Distros (OpenWrt among them) may ship jsoncpp with only a pkg-config
file. Config-mode find_package() then finds nothing - or worse, when
cross-compiling, finds the build host's config and links a foreign-
architecture library. Try pkg-config, which handles cross-compilation
correctly, before resorting to FetchContent.

--- a/extern/libwebem/CMakeLists.txt
+++ b/extern/libwebem/CMakeLists.txt
@@ -171,9 +171,20 @@ elseif(TARGET jsoncpp_lib)
     target_link_libraries(webem PUBLIC jsoncpp_lib)
 else()
     find_package(jsoncpp QUIET)
-    if(jsoncpp_FOUND)
+    if(NOT TARGET jsoncpp_lib)
+        # No usable cmake config for jsoncpp (when cross-compiling, a host
+        # config must not count); pkg-config gets cross-compilation right.
+        find_package(PkgConfig QUIET)
+        if(PKG_CONFIG_FOUND)
+            pkg_check_modules(JSONCPP IMPORTED_TARGET jsoncpp)
+        endif()
+    endif()
+    if(TARGET jsoncpp_lib)
         message(STATUS "webem: using system jsoncpp")
         target_link_libraries(webem PUBLIC jsoncpp_lib)
+    elseif(TARGET PkgConfig::JSONCPP)
+        message(STATUS "webem: using pkg-config jsoncpp")
+        target_link_libraries(webem PUBLIC PkgConfig::JSONCPP)
     else()
         message(STATUS "webem: fetching jsoncpp 1.9.6 via FetchContent")
         set(JSONCPP_WITH_TESTS              OFF CACHE BOOL "" FORCE)