Add preliminary NetBSD support in libfuzzer

Summary:
This code already works and passes some number of tests.

There is need to finish remaining sanitizers to get better coverage.

Many tests fail due to overly long file names of executables (>31).
This is a current shortcoming of the NetBSD 8(beta) kernel, as
certain functions can fail (like retrieving file name of executable).

Sponsored by <The NetBSD Foundation>

Reviewers: joerg, kcc, vitalybuka, george.karpenkov

Reviewed By: kcc

Subscribers: mgorny, llvm-commits, #sanitizers

Tags: #sanitizers

Differential Revision: https://reviews.llvm.org/D37304

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk/lib/fuzzer@312183 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/afl/afl_driver.cpp b/afl/afl_driver.cpp
index 15bceb8..f102479 100644
--- a/afl/afl_driver.cpp
+++ b/afl/afl_driver.cpp
@@ -68,9 +68,15 @@
 #ifdef __linux__
 #define LIBFUZZER_LINUX 1
 #define LIBFUZZER_APPLE 0
+#define LIBFUZZER_NETBSD 0
 #elif __APPLE__
 #define LIBFUZZER_LINUX 0
 #define LIBFUZZER_APPLE 1
+#define LIBFUZZER_NETBSD 0
+#elif __NetBSD__
+#define LIBFUZZER_LINUX 0
+#define LIBFUZZER_APPLE 0
+#define LIBFUZZER_NETBSD 1
 #else
 #error "Support for your platform has not been implemented"
 #endif
@@ -119,7 +125,7 @@
   struct rusage usage;
   if (getrusage(RUSAGE_SELF, &usage))
     return 0;
-  if (LIBFUZZER_LINUX) {
+  if (LIBFUZZER_LINUX || LIBFUZZER_NETBSD) {
     // ru_maxrss is in KiB
     return usage.ru_maxrss >> 10;
   } else if (LIBFUZZER_APPLE) {