make fuzz test optional like autoconf

This makes running the fuzz tests as part of the "make test" rule
optional. Even with this off by default, if building tests is enabled,
the fuzz test will still be compiled, and is available to run via "make
fuzz". This should enable a weekly jenkins build config to run the fuzz
tests, given that it takes a long time to run.

Signed-off-by: Kimball Thurston <kdt3rd@gmail.com>

CMakeLists.txt

@@ -26,6 +26,10 @@ option(OPENEXR_BUILD_OPENEXR        "Build OpenEXR"              ON)
 option(OPENEXR_BUILD_PYTHON_LIBS    "Build the Python bindings"  ON)
 option(OPENEXR_BUILD_VIEWERS        "Build the viewers"          OFF)
 option(OPENEXR_BUILD_TESTS          "Enable the tests"           ON)
+# when enabled, adds the (long) running fuzz tests to the "make test" rule
+# even when this is disabled, as long as OPENEXR_BUILD_TESTS is enabled, one
+# can still run "make fuzz" (or equivalent)
+option(OPENEXR_RUN_FUZZ_TESTS       "Run damaged-input tests"    OFF)
 option(OPENEXR_BUILD_UTILS          "Build the utility programs" ON)
 
 option(OPENEXR_BUILD_SHARED         "Build Shared Libraries"     ON)

OpenEXR/IlmImfFuzzTest/CMakeLists.txt

@@ -19,4 +19,13 @@ TARGET_LINK_LIBRARIES ( IlmImfFuzzTest
   IlmBase::IlmThread${OPENEXR_TARGET_SUFFIX}
   ${PTHREAD_LIB} ${ZLIB_LIBRARIES})
 
-ADD_TEST ( TestIlmImfFuzz IlmImfFuzzTest )
+IF ( OPENEXR_RUN_FUZZ_TESTS )
+  ADD_TEST ( TestIlmImfFuzz IlmImfFuzzTest )
+  # This takes a really long time to run... the default timeout is 1500 seconds or
+  # but this can take 10 hours to run on an older machine
+  SET_TESTS_PROPERTIES ( TestIlmImfFuzz PROPERTIES TIMEOUT 36000 )
+ENDIF ()
+
+ADD_CUSTOM_TARGET(fuzz ${CMAKE_CURRENT_BINARY_DIR}/IlmImfFuzzTest)
+# the depends you can add in ADD_CUSTOM_TARGET only works for other add_custom_command
+ADD_DEPENDENCIES(fuzz IlmImfFuzzTest)