tests : model metadata loading from huggingface (ggml-org#19796)

* Add model metadata loading from huggingface for use with other tests

* Add incremental chunking instead of full redownload, fix caching issue and add warning when it fails

* Add support for split models, load metadata from each individual split file, also avoid mmproj

* Code cleanup, revert incremental downloading

* Only compile when cpp-httplib has SSL support

* Fix formatting

Author: bartowski1182

tests/CMakeLists.txt

@@ -257,6 +257,21 @@ set(LLAMA_TEST_NAME test-mtmd-c-api)
 llama_build_and_test(test-mtmd-c-api.c)
 target_link_libraries(${LLAMA_TEST_NAME} PRIVATE mtmd)
 
+# GGUF model data fetcher library for tests that need real model metadata
+# Only compile when cpp-httplib has SSL support (CPPHTTPLIB_OPENSSL_SUPPORT)
+if (TARGET cpp-httplib)
+    get_target_property(_cpp_httplib_defs cpp-httplib INTERFACE_COMPILE_DEFINITIONS)
+    if (_cpp_httplib_defs MATCHES "CPPHTTPLIB_OPENSSL_SUPPORT")
+        add_library(gguf-model-data STATIC gguf-model-data.cpp)
+        target_link_libraries(gguf-model-data PRIVATE common cpp-httplib)
+        target_include_directories(gguf-model-data PUBLIC ${CMAKE_CURRENT_SOURCE_DIR})
+
+        add_executable(test-gguf-model-data test-gguf-model-data.cpp)
+        target_link_libraries(test-gguf-model-data PRIVATE gguf-model-data common)
+        llama_test(test-gguf-model-data LABEL "model")
+    endif()
+endif()
+
 # dummy executable - not installed
 get_filename_component(TEST_TARGET test-c.c NAME_WE)
 add_executable(${TEST_TARGET} test-c.c)