[lsan] Add an interface function for on-demand leak checking.

Summary:
Add an interface function which can be used to periodically trigger
leak detection in a long-running process.

NB: The meaning of the kIgnored tag has been changed to allow easy clean-up
between subsequent leak checks. Previously, this tag was applied to explicitly
ignored (i.e. with __lsan_disable() or __lsan_ignore_object()) chunks *and* any
chunks only reachable from those. With this change, it's only applied to
explicitly ignored chunks.

Reviewers: samsonov

Reviewed By: samsonov

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D9159

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@235728 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 32 insertions, 0 deletions

diff --git a/test/lsan/TestCases/recoverable_leak_check.cc b/test/lsan/TestCases/recoverable_leak_check.cc
new file mode 100644
index 000000000..0fe377f65
--- /dev/null
+++ b/test/lsan/TestCases/recoverable_leak_check.cc
@@ -0,0 +1,32 @@
+// Test for on-demand leak checking.
+// RUN: LSAN_BASE="use_stacks=0:use_registers=0"
+// RUN: %clangxx_lsan %s -o %t
+// RUN: LSAN_OPTIONS=$LSAN_BASE %run %t foo 2>&1 | FileCheck %s
+// RUN: LSAN_OPTIONS=$LSAN_BASE %run %t 2>&1 | FileCheck %s
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sanitizer/lsan_interface.h>
+
+void *p;
+
+int main(int argc, char *argv[]) {
+  p = malloc(23);
+
+  assert(__lsan_do_recoverable_leak_check() == 0);
+
+  fprintf(stderr, "Test alloc: %p.\n", malloc(1337));
+// CHECK: Test alloc:
+
+  assert(__lsan_do_recoverable_leak_check() == 1);
+// CHECK: SUMMARY: {{(Leak|Address)}}Sanitizer: 1337 byte
+
+  // Test that we correctly reset chunk tags.
+  p = 0;
+  assert(__lsan_do_recoverable_leak_check() == 1);
+// CHECK: SUMMARY: {{(Leak|Address)}}Sanitizer: 1360 byte
+
+  _exit(0);
+}