[GWP-ASan] Configuration options [3].

Summary:
See D60593 for further information.

This patch introduces the configuration options for GWP-ASan. In general, we expect the supporting allocator to populate the options struct, and give that to GWP-ASan during initialisation. For allocators that are okay with pulling in sanitizer_common, we also provide an optional parser that populates the gwp_asan::Options struct with values provided in the GWP_ASAN_OPTIONS environment variable.

This patch contains very little logic, and all of the testable components (i.e. the optional parser's internal logic) is tested as part of the sanitizer_common testbed.

Reviewers: vlad.tsyrklevich, morehouse, jfb

Reviewed By: morehouse

Subscribers: dexonsmith, kubamracek, mgorny, #sanitizers, llvm-commits, vitalybuka

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D62698

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@362527 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 48 insertions, 0 deletions

diff --git a/lib/gwp_asan/CMakeLists.txt b/lib/gwp_asan/CMakeLists.txt
index 6c83d86c6..771192f23 100644
--- a/lib/gwp_asan/CMakeLists.txt
+++ b/lib/gwp_asan/CMakeLists.txt
@@ -10,6 +10,8 @@ set(GWP_ASAN_SOURCES
 set(GWP_ASAN_HEADERS
   mutex.h
   random.h
+  options.h
+  options.inc
 )
 
 # Ensure that GWP-ASan meets the delegated requirements of some supporting
@@ -20,6 +22,26 @@ set(GWP_ASAN_CFLAGS -fno-rtti -fno-exceptions -nostdinc++ -pthread)
 # Remove -stdlib= which is unused when passing -nostdinc++.
 string(REGEX REPLACE "-stdlib=[a-zA-Z+]*" "" CMAKE_CXX_FLAGS ${CMAKE_CXX_FLAGS})
 
+# Options parsing support is optional. GwpAsan is totally independent of
+# sanitizer_common, the options parser is not. This is an optional library
+# that can be used by an allocator to automatically parse GwpAsan options from
+# the environment variable GWP_ASAN_FLAGS, but the allocator can choose to
+# implement its own options parsing and populate the Options struct itself.
+set(GWP_ASAN_OPTIONS_PARSER_SOURCES
+  optional/options_parser.cpp
+)
+set(GWP_ASAN_OPTIONS_PARSER_HEADERS
+  optional/options_parser.h
+  options.h
+  options.inc
+)
+set(GWP_ASAN_OPTIONS_PARSER_CFLAGS
+    ${GWP_ASAN_CFLAGS}
+    ${SANITIZER_COMMON_CFLAGS})
+set(GWP_ASAN_OPTIONS_PARSER_OBJECT_LIBS
+    RTSanitizerCommon
+    RTSanitizerCommonNoLibc)
+
 if (COMPILER_RT_HAS_GWP_ASAN)
   foreach(arch ${GWP_ASAN_SUPPORTED_ARCH})
     add_compiler_rt_runtime(
@@ -38,6 +60,32 @@ if (COMPILER_RT_HAS_GWP_ASAN)
       SOURCES ${GWP_ASAN_SOURCES}
       ADDITIONAL_HEADERS ${GWP_ASAN_HEADERS}
       CFLAGS ${GWP_ASAN_CFLAGS})
+
+  # Note: If you choose to add this as an object library, ensure you also
+  # include the sanitizer_common flag parsing object lib (generally
+  # 'RTSanitizerCommonNoTermination').
+  add_compiler_rt_object_libraries(RTGwpAsanOptionsParser
+      ARCHS ${GWP_ASAN_SUPPORTED_ARCH}
+      SOURCES ${GWP_ASAN_OPTIONS_PARSER_SOURCES}
+      ADDITIONAL_HEADERS ${GWP_ASAN_OPTIONS_PARSER_HEADERS}
+      CFLAGS ${GWP_ASAN_OPTIONS_PARSER_CFLAGS})
+
+  # Ensure that the build for the options parser succeeds, as
+  # 'RTGwpAsanOptionsParser' may not be built if it's not needed. This library
+  # has only a very small amount of logic, all of the testable components are
+  # exercised in the sanitizer_common test suite.
+  foreach(arch ${GWP_ASAN_SUPPORTED_ARCH})
+    add_compiler_rt_runtime(
+      clang_rt.gwp_asan_options_parser
+      SHARED
+      ARCHS ${arch}
+      SOURCES ${GWP_ASAN_OPTIONS_PARSER_SOURCES}
+      ADDITIONAL_HEADERS ${GWP_ASAN_OPTIONS_PARSER_HEADERS}
+      CFLAGS ${GWP_ASAN_OPTIONS_PARSER_CFLAGS}
+      OBJECT_LIBS ${GWP_ASAN_OPTIONS_PARSER_OBJECT_LIBS}
+      PARENT_TARGET gwp_asan
+    )
+  endforeach()
 endif()
 
 if(COMPILER_RT_INCLUDE_TESTS)