[LSan] Make parent tool responsible for initializing LSan flags.

Summary:
LSan can be combined with a parent tool (for now it's only ASan).
Also, we allow LSAN_OPTIONS to override certain common flags. It means
we have to parse LSAN_OPTIONS early enough, before the rest of the
parent tool (including chunks of sanitizer_common) is initialized.

In future, we can use the same approach for UBSan, after we embed it
into ASan runtime in a similar way.

Test Plan: regression test suite

Reviewers: earthdok, eugenis

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D7577

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@229519 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 39 insertions, 38 deletions

diff --git a/lib/lsan/lsan.cc b/lib/lsan/lsan.cc
index 1509b2a7d..6018f7bf6 100644
--- a/lib/lsan/lsan.cc
+++ b/lib/lsan/lsan.cc
@@ -15,6 +15,7 @@
 #include "lsan.h"
 
 #include "sanitizer_common/sanitizer_flags.h"
+#include "sanitizer_common/sanitizer_flag_parser.h"
 #include "sanitizer_common/sanitizer_stacktrace.h"
 #include "lsan_allocator.h"
 #include "lsan_common.h"
@@ -34,13 +35,42 @@ bool WordIsPoisoned(uptr addr) {
 
 using namespace __lsan;  // NOLINT
 
+static void InitializeFlags() {
+  // Set all the default values.
+  SetCommonFlagsDefaults();
+  {
+    CommonFlags cf;
+    cf.CopyFrom(*common_flags());
+    cf.external_symbolizer_path = GetEnv("LSAN_SYMBOLIZER_PATH");
+    cf.malloc_context_size = 30;
+    cf.detect_leaks = true;
+    OverrideCommonFlags(cf);
+  }
+
+  Flags *f = flags();
+  f->SetDefaults();
+
+  FlagParser parser;
+  RegisterLsanFlags(&parser, f);
+  RegisterCommonFlags(&parser);
+
+  parser.ParseString(GetEnv("LSAN_OPTIONS"));
+
+  SetVerbosity(common_flags()->verbosity);
+
+  if (Verbosity()) ReportUnrecognizedFlags();
+
+  if (common_flags()->help) parser.PrintFlagDescriptions();
+}
+
 extern "C" void __lsan_init() {
   CHECK(!lsan_init_is_running);
   if (lsan_inited)
     return;
   lsan_init_is_running = true;
   SanitizerToolName = "LeakSanitizer";
-  InitCommonLsan(true);
+  InitializeFlags();
+  InitCommonLsan();
   InitializeAllocator();
   InitTlsSize();
   InitializeInterceptors();
diff --git a/lib/lsan/lsan_common.cc b/lib/lsan/lsan_common.cc
index 7b3cd1639..5a2f25cf8 100644
--- a/lib/lsan/lsan_common.cc
+++ b/lib/lsan/lsan_common.cc
@@ -43,46 +43,13 @@ void Flags::SetDefaults() {
 #undef LSAN_FLAG
 }
 
-static void RegisterLsanFlags(FlagParser *parser, Flags *f) {
+void RegisterLsanFlags(FlagParser *parser, Flags *f) {
 #define LSAN_FLAG(Type, Name, DefaultValue, Description) \
   RegisterFlag(parser, #Name, Description, &f->Name);
 #include "lsan_flags.inc"
 #undef LSAN_FLAG
 }
 
-static void InitializeFlags(bool standalone) {
-  Flags *f = flags();
-  FlagParser parser;
-  RegisterLsanFlags(&parser, f);
-  RegisterCommonFlags(&parser);
-
-  f->SetDefaults();
-
-  // Set defaults for common flags (only in standalone mode) and parse
-  // them from LSAN_OPTIONS.
-  if (standalone) {
-    SetCommonFlagsDefaults();
-    CommonFlags cf;
-    cf.CopyFrom(*common_flags());
-    cf.external_symbolizer_path = GetEnv("LSAN_SYMBOLIZER_PATH");
-    cf.malloc_context_size = 30;
-    cf.detect_leaks = true;
-    OverrideCommonFlags(cf);
-  }
-
-  bool help_before = common_flags()->help;
-
-  const char *options = GetEnv("LSAN_OPTIONS");
-  parser.ParseString(options);
-
-  SetVerbosity(common_flags()->verbosity);
-
-  if (Verbosity()) ReportUnrecognizedFlags();
-
-  if (!help_before && common_flags()->help)
-    parser.PrintFlagDescriptions();
-}
-
 #define LOG_POINTERS(...)                           \
   do {                                              \
     if (flags()->log_pointers) Report(__VA_ARGS__); \
@@ -116,8 +83,7 @@ void InitializeRootRegions() {
   root_regions = new(placeholder) InternalMmapVector<RootRegion>(1);
 }
 
-void InitCommonLsan(bool standalone) {
-  InitializeFlags(standalone);
+void InitCommonLsan() {
   InitializeRootRegions();
   if (common_flags()->detect_leaks) {
     // Initialization which can fail or print warnings should only be done if
diff --git a/lib/lsan/lsan_common.h b/lib/lsan/lsan_common.h
index 64cbef38c..edb38ff47 100644
--- a/lib/lsan/lsan_common.h
+++ b/lib/lsan/lsan_common.h
@@ -27,6 +27,10 @@
 #define CAN_SANITIZE_LEAKS 0
 #endif
 
+namespace __sanitizer {
+class FlagParser;
+}
+
 namespace __lsan {
 
 // Chunk tags.
@@ -50,6 +54,7 @@ struct Flags {
 
 extern Flags lsan_flags;
 inline Flags *flags() { return &lsan_flags; }
+void RegisterLsanFlags(FlagParser *parser, Flags *f);
 
 struct Leak {
   u32 id;
@@ -105,7 +110,7 @@ enum IgnoreObjectResult {
 };
 
 // Functions called from the parent tool.
-void InitCommonLsan(bool standalone);
+void InitCommonLsan();
 void DoLeakCheck();
 bool DisabledInThisThread();