Add MinidumpCrashpadInfoWriter and its test

minidump/minidump_string_writer_test_util.cc

Index: minidump/minidump_string_writer_test_util.cc
diff --git a/minidump/minidump_string_writer_test_util.cc b/minidump/minidump_string_writer_test_util.cc
new file mode 100644
index 0000000000000000000000000000000000000000..7914c68ab5c31d6048e516ec5dedc9d504615bf6
--- /dev/null
+++ b/minidump/minidump_string_writer_test_util.cc
@@ -0,0 +1,56 @@
+// Copyright 2014 The Crashpad Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "minidump/minidump_string_writer_test_util.h"
+
+#include "gtest/gtest.h"
+#include "minidump/minidump_extensions.h"
+
+namespace crashpad {
+namespace test {
+
+std::string MinidumpUTF8StringAtRVA(const StringFileWriter& file_writer,
+                                    RVA rva) {
+  const std::string& contents = file_writer.string();
+  if (rva == 0) {
+    return std::string();
+  }
+
+  if (rva + sizeof(MinidumpUTF8String) > contents.size()) {
+    ADD_FAILURE()
+        << "rva " << rva << " too large for contents " << contents.size();
+    return std::string();
+  }
+
+  const MinidumpUTF8String* minidump_string =
+      reinterpret_cast<const MinidumpUTF8String*>(&contents[rva]);
+
+  // Verify that the file has enough data for the string’s stated length plus
+  // its required NUL terminator.
+  if (rva + sizeof(MinidumpUTF8String) + minidump_string->Length + 1 >
+          contents.size()) {
+    ADD_FAILURE()
+        << "rva " << rva << ", length " << minidump_string->Length
+        << " too large for contents " << contents.size();
+    return std::string();
+  }
+
+  std::string minidump_string_data(
+      reinterpret_cast<const char*>(&minidump_string->Buffer[0]),
+      minidump_string->Length);
+  return minidump_string_data;
+}
+
+}  // namespace test
+}  // namespace crashpad