Fix mixed in/out of source builds.

[apitrace] / thirdparty / snappy / CMakeLists.txt

diff --git a/thirdparty/snappy/CMakeLists.txt b/thirdparty/snappy/CMakeLists.txt
index 92d12482ef08a7f02874b11a1e5a063ab1b94b43..bcacda7514a8acf632548d73fcff59e01d78d161 100644 (file)
--- a/thirdparty/snappy/CMakeLists.txt
+++ b/thirdparty/snappy/CMakeLists.txt
@@ -1,4 +1,38 @@
-include_directories(${CMAKE_CURRENT_SOURCE_DIR})
+# We only do the subset of the snappy autoconf that actually affect the library
+# (as most of them are for the tests which we don't build.)
+
+include (CheckIncludeFileCXX)
+include (CheckCXXSourceCompiles)
+include (TestBigEndian)
+
+check_include_file_cxx (sys/mman.h HAVE_SYS_MMAN_H)
+check_include_file_cxx (sys/byteorder.h HAVE_SYS_BYTEORDER_H)
+check_include_file_cxx (sys/endian.h HAVE_SYS_ENDIAN_H)
+check_include_file_cxx (byteswap.h HAVE_BYTESWAP_H)
+
+check_cxx_source_compiles (
+    "main() { return __builtin_expect(1, 1) ? 1 : 0; }"
+    HAVE_BUILTIN_EXPECT
+)
+
+check_cxx_source_compiles (
+    "main() { return (__builtin_ctzll(0x100000000LL) == 32) ? 1 : 0; }"
+    HAVE_BUILTIN_CTZ
+)
+
+test_big_endian (WORDS_BIGENDIAN)
+
+configure_file (config.h.in config.h)
+
+add_definitions (-DHAVE_CONFIG_H)
+
+# Adjust warnings
+if (CMAKE_COMPILER_IS_GNUCXX)
+    add_definitions (-Wno-unused-function)
+endif ()
+
+
+include_directories (${CMAKE_CURRENT_BINARY_DIR})
 
 add_library (snappy_bundled STATIC
     snappy.cc
@@ -10,3 +44,12 @@ add_library (snappy_bundled STATIC
 set_target_properties (snappy_bundled PROPERTIES
     COMPILE_FLAGS "${CMAKE_SHARED_LIBRARY_CXX_FLAGS}"
 )
+
+# If we're doing an out of source build remove any config.h from the source tree.
+if (NOT CMAKE_CURRENT_SOURCE_DIR STREQUAL CMAKE_CURRENT_BINARY_DIR)
+    add_custom_command (
+        TARGET snappy_bundled
+        PRE_BUILD
+        COMMAND ${CMAKE_COMMAND} -E remove -f ${CMAKE_CURRENT_SOURCE_DIR}/config.h
+    )
+endif()