Add writeAsBinary(raw_ostream &) method to BinaryRef.

Previously, yaml2coff.cpp had a writeHexData static helper function to
do this, but it is generally useful functionality.

Also, validate hex strings up-front to avoid running having to handle
errors "deep inside" the yaml2obj code (it also gives better diagnostics
than it used to).

llvm-svn: 183345

1 files changed, 29 insertions, 0 deletions

diff --git a/llvm/lib/Object/YAML.cpp b/llvm/lib/Object/YAML.cpp
index 36b19974b0e..b33cf3410f6 100644
--- a/llvm/lib/Object/YAML.cpp
+++ b/llvm/lib/Object/YAML.cpp
@@ -13,8 +13,10 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Object/YAML.h"
+#include "llvm/Support/raw_ostream.h"
 
 using namespace llvm;
+using namespace object::yaml;
 
 void yaml::ScalarTraits<object::yaml::BinaryRef>::output(
     const object::yaml::BinaryRef &Val, void *, llvm::raw_ostream &Out) {
@@ -27,8 +29,35 @@ void yaml::ScalarTraits<object::yaml::BinaryRef>::output(
   }
 }
 
+// Can't find this anywhere else in the codebase (clang has one, but it has
+// some baggage). Deduplicate as required.
+static bool isHexDigit(uint8_t C) {
+  return ('0' <= C && C <= '9') ||
+         ('A' <= C && C <= 'F') ||
+         ('a' <= C && C <= 'f');
+}
+
 StringRef yaml::ScalarTraits<object::yaml::BinaryRef>::input(
     StringRef Scalar, void *, object::yaml::BinaryRef &Val) {
+  if (Scalar.size() % 2 != 0)
+    return "BinaryRef hex string must contain an even number of nybbles.";
+  // TODO: Can we improve YAMLIO to permit a more accurate diagnostic here?
+  // (e.g. a caret pointing to the offending character).
+  for (unsigned I = 0, N = Scalar.size(); I != N; ++I)
+    if (!isHexDigit(Scalar[I]))
+      return "BinaryRef hex string must contain only hex digits.";
   Val = object::yaml::BinaryRef(Scalar);
   return StringRef();
 }
+
+void BinaryRef::writeAsBinary(raw_ostream &OS) const {
+  if (isBinary) {
+    OS.write((const char *)Data.data(), Data.size());
+    return;
+  }
+  for (unsigned I = 0, N = Data.size(); I != N; I += 2) {
+    uint8_t Byte;
+    StringRef((const char *)&Data[I],  2).getAsInteger(16, Byte);
+    OS.write(Byte);
+  }
+}