Use an option instead of a flag for USE_BUNDLED_ZLIB

Now `USE_BUNDLED_ZLIB` can be set to the string `Chromium` to enable the
Chromium implementation of zlib.

Author: lhchavez

CMakeLists.txt

@@ -50,8 +50,7 @@ OPTION(USE_STANDALONE_FUZZERS		"Enable standalone fuzzers (compatible with gcc)"
 OPTION(USE_LEAK_CHECKER			"Run tests with leak checker"				OFF)
 OPTION(DEBUG_POOL			"Enable debug pool allocator"				OFF)
 OPTION(ENABLE_WERROR			"Enable compilation with -Werror"			OFF)
-OPTION(USE_BUNDLED_ZLIB    		"Use the bundled version of zlib"			OFF)
-OPTION(USE_CHROMIUM_ZLIB   		"If using the bundled version of zlib, use the Chromium flavor (x86_64 processor with SSE4.2 and CLMUL required)"			OFF)
+OPTION(USE_BUNDLED_ZLIB    		"Use the bundled version of zlib. Can be set to one of Bundled(ON)/Chromium. The Chromium option requires a x86_64 processor with SSE4.2 and CLMUL"			OFF)
    SET(USE_HTTP_PARSER			"" CACHE STRING "Specifies the HTTP Parser implementation; either system or builtin.")
 OPTION(DEPRECATE_HARD			"Do not include deprecated functions in the library"	OFF)
    SET(REGEX_BACKEND			"" CACHE STRING "Regular expression implementation. One of regcomp_l, pcre2, pcre, regcomp, or builtin.")

src/CMakeLists.txt

@@ -7,6 +7,7 @@ ENDIF()
 ADD_FEATURE_INFO(debugpool GIT_DEBUG_POOL "debug pool allocator")
 
 INCLUDE(PkgBuildConfig)
+INCLUDE(SanitizeBool)
 
 # This variable will contain the libraries we need to put into
 # libgit2.pc's Requires.private. That is, what we're linking to or
@@ -186,7 +187,12 @@ ELSE()
 ENDIF()
 
 # Optional external dependency: zlib
-IF(NOT USE_BUNDLED_ZLIB)
+SanitizeBool(USE_BUNDLED_ZLIB)
+IF(USE_BUNDLED_ZLIB STREQUAL ON)
+	SET(USE_BUNDLED_ZLIB "Bundled")
+ENDIF()
+
+IF(USE_BUNDLED_ZLIB STREQUAL "OFF")
 	FIND_PACKAGE(ZLIB)
 	IF(ZLIB_FOUND)
 		LIST(APPEND LIBGIT2_SYSTEM_INCLUDES ${ZLIB_INCLUDE_DIRS})
@@ -201,18 +207,16 @@ IF(NOT USE_BUNDLED_ZLIB)
 		MESSAGE(STATUS "zlib was not found; using bundled 3rd-party sources." )
 	ENDIF()
 ENDIF()
-IF(USE_BUNDLED_ZLIB OR NOT ZLIB_FOUND)
-	IF(USE_CHROMIUM_ZLIB)
-		ADD_SUBDIRECTORY("${libgit2_SOURCE_DIR}/deps/chromium-zlib" "${libgit2_BINARY_DIR}/deps/chromium-zlib")
-		LIST(APPEND LIBGIT2_INCLUDES "${libgit2_SOURCE_DIR}/deps/chromium-zlib")
-		LIST(APPEND LIBGIT2_OBJECTS $<TARGET_OBJECTS:chromium_zlib>)
-		ADD_FEATURE_INFO(zlib ON "using (Chromium) bundled zlib")
-	ELSE()
-		ADD_SUBDIRECTORY("${libgit2_SOURCE_DIR}/deps/zlib" "${libgit2_BINARY_DIR}/deps/zlib")
-		LIST(APPEND LIBGIT2_INCLUDES "${libgit2_SOURCE_DIR}/deps/zlib")
-		LIST(APPEND LIBGIT2_OBJECTS $<TARGET_OBJECTS:zlib>)
-		ADD_FEATURE_INFO(zlib ON "using bundled zlib")
-	ENDIF()
+IF(USE_BUNDLED_ZLIB STREQUAL "Chromium")
+	ADD_SUBDIRECTORY("${libgit2_SOURCE_DIR}/deps/chromium-zlib" "${libgit2_BINARY_DIR}/deps/chromium-zlib")
+	LIST(APPEND LIBGIT2_INCLUDES "${libgit2_SOURCE_DIR}/deps/chromium-zlib")
+	LIST(APPEND LIBGIT2_OBJECTS $<TARGET_OBJECTS:chromium_zlib>)
+	ADD_FEATURE_INFO(zlib ON "using (Chromium) bundled zlib")
+ELSEIF(USE_BUNDLED_ZLIB OR NOT ZLIB_FOUND)
+	ADD_SUBDIRECTORY("${libgit2_SOURCE_DIR}/deps/zlib" "${libgit2_BINARY_DIR}/deps/zlib")
+	LIST(APPEND LIBGIT2_INCLUDES "${libgit2_SOURCE_DIR}/deps/zlib")
+	LIST(APPEND LIBGIT2_OBJECTS $<TARGET_OBJECTS:zlib>)
+	ADD_FEATURE_INFO(zlib ON "using bundled zlib")
 ENDIF()
 
 # Optional external dependency: libssh2