ART: Fix Trace types, check minimum buf size

Also make streaming mode adhere to the given buffer (and fix the
case where the buffer is too small for a packet). This is important
to not lose too much tracing information when the runtime is destroyed
with an unflushed buffer.

Change-Id: I6525fe4326ac5c3d7c9cda41c54a2a911ca889b7

1 files changed, 19 insertions, 0 deletions

diff --git a/runtime/base/casts.h b/runtime/base/casts.h
index c7e39a29fb..f8846498df 100644
--- a/runtime/base/casts.h
+++ b/runtime/base/casts.h
@@ -18,9 +18,11 @@
 #define ART_RUNTIME_BASE_CASTS_H_
 
 #include <assert.h>
+#include <limits>
 #include <string.h>
 #include <type_traits>
 
+#include "base/logging.h"
 #include "base/macros.h"
 
 namespace art {
@@ -83,6 +85,23 @@ inline Dest bit_cast(const Source& source) {
   return dest;
 }
 
+// A version of static_cast that DCHECKs that the value can be precisely represented
+// when converting to Dest.
+template <typename Dest, typename Source>
+inline Dest dchecked_integral_cast(const Source source) {
+  DCHECK(
+      // Check that the value is within the lower limit of Dest.
+      (static_cast<intmax_t>(std::numeric_limits<Dest>::min()) <=
+          static_cast<intmax_t>(std::numeric_limits<Source>::min()) ||
+          source >= static_cast<Source>(std::numeric_limits<Dest>::min())) &&
+      // Check that the value is within the upper limit of Dest.
+      (static_cast<uintmax_t>(std::numeric_limits<Dest>::max()) >=
+          static_cast<uintmax_t>(std::numeric_limits<Source>::max()) ||
+          source <= static_cast<Source>(std::numeric_limits<Dest>::max())));
+
+  return static_cast<Dest>(source);
+}
+
 }  // namespace art
 
 #endif  // ART_RUNTIME_BASE_CASTS_H_