Lex: Add some unit tests for corrupt header maps

Split the implementation of `HeaderMap` into `HeaderMapImpl` so that we
can write unit tests that don't depend on the `FileManager`, and then
write a few tests that cover the types of corrupt header maps already
detected.

This also moves type and constant definitions from HeaderMap.cpp to
HeaderMapTypes.h so that the test can access them.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@261446 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 43 insertions, 0 deletions

diff --git a/include/clang/Lex/HeaderMapTypes.h b/include/clang/Lex/HeaderMapTypes.h
new file mode 100644
index 0000000000..fbaf4baee4
--- /dev/null
+++ b/include/clang/Lex/HeaderMapTypes.h
@@ -0,0 +1,43 @@
+//===- HeaderMapTypes.h - Types for the header map format -------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_LEX_HEADERMAPTYPES_H
+#define LLVM_CLANG_LEX_HEADERMAPTYPES_H
+
+#include <cstdint>
+
+namespace clang {
+
+enum {
+  HMAP_HeaderMagicNumber = ('h' << 24) | ('m' << 16) | ('a' << 8) | 'p',
+  HMAP_HeaderVersion = 1,
+  HMAP_EmptyBucketKey = 0
+};
+
+struct HMapBucket {
+  uint32_t Key;    // Offset (into strings) of key.
+  uint32_t Prefix; // Offset (into strings) of value prefix.
+  uint32_t Suffix; // Offset (into strings) of value suffix.
+};
+
+struct HMapHeader {
+  uint32_t Magic;          // Magic word, also indicates byte order.
+  uint16_t Version;        // Version number -- currently 1.
+  uint16_t Reserved;       // Reserved for future use - zero for now.
+  uint32_t StringsOffset;  // Offset to start of string pool.
+  uint32_t NumEntries;     // Number of entries in the string table.
+  uint32_t NumBuckets;     // Number of buckets (always a power of 2).
+  uint32_t MaxValueLength; // Length of longest result path (excluding nul).
+  // An array of 'NumBuckets' HMapBucket objects follows this header.
+  // Strings follow the buckets, at StringsOffset.
+};
+
+} // end namespace clang.
+
+#endif