Issue-5369-Fix CMake Oauthbearer OIDC on Windows

[Marc Gutman (icanhasmath)]

Define the same conditions for WITH_OAUTHBEARER_OIDC in Cmake as are defined at the top level CMakelists.txt

Closes #5369

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[Copilot]

Pull request overview

This PR addresses #5369 by aligning Windows CMake builds (when WITHOUT_WIN32_CONFIG is enabled) with the top-level CMakeLists.txt feature gating so that WITH_OAUTHBEARER_OIDC is reflected correctly at compile time when WITH_CURL and WITH_SSL are enabled.

Changes:

• Add WITH_CURL compile definitions (1/0) under the WITHOUT_WIN32_CONFIG path.
• Add WITH_OAUTHBEARER_OIDC compile definitions gated on WITH_SSL AND WITH_CURL under the WITHOUT_WIN32_CONFIG path.

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[Copilot]

Defining WITH_OAUTHBEARER_OIDC=0 still makes the macro defined, which can unintentionally enable #ifdef WITH_OAUTHBEARER_OIDC code paths. In particular, src/rdkafka_conf.c includes <curl/curl.h> under #ifdef WITH_OAUTHBEARER_OIDC, so this change can force a curl header dependency even when WITH_CURL/OIDC are disabled and break builds where libcurl headers aren't present. Prefer only defining WITH_OAUTHBEARER_OIDC when it is enabled (omit the =0 definition), or switch the C code to #if WITH_OAUTHBEARER_OIDC so 0 behaves as disabled.

Suggested change

	else()
	list(APPEND rdkafka_compile_definitions WITH_OAUTHBEARER_OIDC=0)

[Copilot]

For maintainability and to avoid condition drift, consider basing the compile definition on the already-derived CMake variable (WITH_OAUTHBEARER_OIDC) rather than duplicating the WITH_SSL AND WITH_CURL condition here.

Suggested change

	if(WITH_SSL AND WITH_CURL)
	list(APPEND rdkafka_compile_definitions WITH_OAUTHBEARER_OIDC=1)
	else()
	list(APPEND rdkafka_compile_definitions WITH_OAUTHBEARER_OIDC=0)
	endif()
	if(WITH_OAUTHBEARER_OIDC)
	list(APPEND rdkafka_compile_definitions WITH_OAUTHBEARER_OIDC=1)
	else()
	list(APPEND rdkafka_compile_definitions WITH_OAUTHBEARER_OIDC=0)
	endif(WITH_OAUTHBEARER_OIDC)

[Copilot]

Minor consistency: the surrounding blocks in this same WITHOUT_WIN32_CONFIG section use endif(<condition>) (e.g., endif(WITH_CURL) / endif(WITH_PLUGINS)). Using endif(WITH_SSL AND WITH_CURL) here as well would keep the style consistent and reduce ambiguity when scanning the file.

Suggested change

	endif()
	endif(WITH_SSL AND WITH_CURL)