build(cmake): use installed cpp-httplib if available

src/libs/core/CMakeLists.txt

@@ -6,14 +6,8 @@ add_library(Core STATIC
     httpserver.cpp
     networkaccessmanager.cpp
     settings.cpp
-
-    # Show headers without .cpp in Qt Creator.
-    httplib.h
 )
 
-# Configure cpp-httplib.
-add_definitions(-DCPPHTTPLIB_USE_POLL)
-
 target_link_libraries(Core Registry Ui)
 
 find_package(Qt${QT_VERSION_MAJOR} COMPONENTS Network WebEngineCore Widgets REQUIRED)
@@ -48,6 +42,18 @@ else()
     target_link_libraries(Core ${LibArchive_LIBRARIES})
 endif()
 
+# Configure cpp-httplib.
+add_definitions(-DCPPHTTPLIB_USE_POLL)
+
+find_package(httplib CONFIG QUIET)
+if(httplib_FOUND)
+    target_link_libraries(Core httplib::httplib)
+else()
+    # Use bundled version of cpp-httplib if not found.
+    # TODO: Replace with QHttpServer once Qt 5 is dropped.
+    include_directories("${CMAKE_SOURCE_DIR}/src/contrib/cpp-httplib")
+endif()
+
 # Required by cpp-httplib.
 if(NOT WIN32)
     set(THREADS_PREFER_PTHREAD_FLAG ON)

src/libs/core/httpserver.cpp

@@ -23,7 +23,8 @@
 #include "httpserver.h"
 
 #include "application.h"
-#include "httplib.h"
+
+#include <httplib.h>
 
 #include <QLoggingCategory>
 #include <QRegularExpression>

vcpkg.json

@@ -1,6 +1,10 @@
 {
   "$schema": "https://raw.githubusercontent.com/microsoft/vcpkg-tool/main/docs/vcpkg.schema.json",
   "dependencies": [
+    {
+      "name": "cpp-httplib",
+      "default-features": false
+    },
     {
       "name": "libarchive",
       "default-features": false