Lex: Return "" when HeaderMap::lookupFilename fails
Change getString() to return Optional<StringRef>, and change
lookupFilename() to return an empty string if either one of the prefix
and suffix can't be found.
This is a more robust follow-up to r261461, but it's still not entirely
satisfactory. Ideally we'd report that the header map is corrupt;
perhaps something for a follow-up.
llvm-svn: 261596
diff --git a/clang/unittests/Lex/HeaderMapTest.cpp b/clang/unittests/Lex/HeaderMapTest.cpp
index ad0579a..d16efe8 100644
--- a/clang/unittests/Lex/HeaderMapTest.cpp
+++ b/clang/unittests/Lex/HeaderMapTest.cpp
@@ -185,7 +185,7 @@
PaddingTy Padding;
};
-TEST(HeaderMapTest, lookupFilenameTruncated) {
+TEST(HeaderMapTest, lookupFilenameTruncatedSuffix) {
typedef MapFile<2, 64 - sizeof(HMapHeader) - 2 * sizeof(HMapBucket)> FileTy;
static_assert(std::is_standard_layout<FileTy>::value,
"Expected standard layout");
@@ -215,10 +215,44 @@
HeaderMapImpl Map(File.getBuffer(), NeedsSwap);
// The string for "c" runs to the end of File. Check that the suffix
- // ("cxxxx...") is ignored. Another option would be to return an empty
- // filename altogether.
+ // ("cxxxx...") is detected as truncated, and an empty string is returned.
SmallString<24> DestPath;
- ASSERT_EQ("b", Map.lookupFilename("a", DestPath));
+ ASSERT_EQ("", Map.lookupFilename("a", DestPath));
+}
+
+TEST(HeaderMapTest, lookupFilenameTruncatedPrefix) {
+ typedef MapFile<2, 64 - sizeof(HMapHeader) - 2 * sizeof(HMapBucket)> FileTy;
+ static_assert(std::is_standard_layout<FileTy>::value,
+ "Expected standard layout");
+ static_assert(sizeof(FileTy) == 64, "check the math");
+ PaddedFile<FileTy, uint64_t> P;
+ auto &File = P.File;
+ auto &Padding = P.Padding;
+ File.init();
+
+ FileMaker<FileTy> Maker(File);
+ auto a = Maker.addString("a");
+ auto c = Maker.addString("c");
+ auto b = Maker.addString("b"); // Store the prefix last.
+ Maker.addBucket(getHash("a"), a, b, c);
+
+ // Add 'x' characters to cause an overflow into Padding.
+ ASSERT_EQ('b', File.Bytes[5]);
+ for (unsigned I = 6; I < sizeof(File.Bytes); ++I) {
+ ASSERT_EQ(0, File.Bytes[I]);
+ File.Bytes[I] = 'x';
+ }
+ Padding = 0xffffffff; // Padding won't stop it either.
+
+ bool NeedsSwap;
+ ASSERT_TRUE(HeaderMapImpl::checkHeader(*File.getBuffer(), NeedsSwap));
+ ASSERT_FALSE(NeedsSwap);
+ HeaderMapImpl Map(File.getBuffer(), NeedsSwap);
+
+ // The string for "b" runs to the end of File. Check that the prefix
+ // ("bxxxx...") is detected as truncated, and an empty string is returned.
+ SmallString<24> DestPath;
+ ASSERT_EQ("", Map.lookupFilename("a", DestPath));
}
} // end namespace