[compiler-rt] reimplements GetMemoryProfile for netbsd. (#84841)

The actual solution relies on the premise /proc/self/smaps existence.
instead relying on native api like freebsd.
fixing fuzzer build too.

Author: devnexen

compiler-rt/lib/fuzzer/FuzzerUtilLinux.cpp

@@ -44,7 +44,7 @@ void SetThreadName(std::thread &thread, const std::string &name) {
 #if LIBFUZZER_LINUX || LIBFUZZER_FREEBSD
   (void)pthread_setname_np(thread.native_handle(), name.c_str());
 #elif LIBFUZZER_NETBSD
-  (void)pthread_set_name_np(thread.native_handle(), "%s", name.c_str());
+  (void)pthread_setname_np(thread.native_handle(), "%s", const_cast<char *>(name.c_str()));
 #endif
 }
 

compiler-rt/lib/sanitizer_common/sanitizer_procmaps_bsd.cpp

@@ -42,6 +42,19 @@ void GetMemoryProfile(fill_profile_f cb, uptr *stats) {
   cb(0, InfoProc->ki_rssize * GetPageSizeCached(), false, stats);
   UnmapOrDie(InfoProc, Size, true);
 }
+#elif SANITIZER_NETBSD
+void GetMemoryProfile(fill_profile_f cb, uptr *stats) {
+  struct kinfo_proc2 *InfoProc;
+  uptr Len = sizeof(*InfoProc);
+  uptr Size = Len;
+  const int Mib[] = {CTL_KERN, KERN_PROC2, KERN_PROC_PID, getpid(), Size, 1};
+  InfoProc = (struct kinfo_proc2 *)MmapOrDie(Size, "GetMemoryProfile()");
+  CHECK_EQ(
+      internal_sysctl(Mib, ARRAY_SIZE(Mib), nullptr, (uptr *)InfoProc, &Len, 0),
+      0);
+  cb(0, InfoProc->p_vm_rssize * GetPageSizeCached(), false, stats);
+  UnmapOrDie(InfoProc, Size, true);
+}
 #endif
 
 void ReadProcMaps(ProcSelfMapsBuff *proc_maps) {

compiler-rt/lib/sanitizer_common/sanitizer_procmaps_common.cpp

@@ -145,7 +145,7 @@ void MemoryMappingLayout::DumpListOfModules(
   }
 }
 
-#if SANITIZER_LINUX || SANITIZER_ANDROID || SANITIZER_SOLARIS || SANITIZER_NETBSD
+#if SANITIZER_LINUX || SANITIZER_ANDROID || SANITIZER_SOLARIS
 void GetMemoryProfile(fill_profile_f cb, uptr *stats) {
   char *smaps = nullptr;
   uptr smaps_cap = 0;