[PathV2] Add mapped_file_region. Implementation for Windows and POSIX.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161976 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/Unix/PathV2.inc b/lib/Support/Unix/PathV2.inc
index 99f8cd4..3bb38f6 100644
--- a/lib/Support/Unix/PathV2.inc
+++ b/lib/Support/Unix/PathV2.inc
@@ -465,6 +465,118 @@
return error_code::success();
}
+error_code mapped_file_region::init(int fd, uint64_t offset) {
+ AutoFD FD(fd);
+
+ // Figure out how large the file is.
+ struct stat FileInfo;
+ if (fstat(fd, &FileInfo) == -1)
+ return error_code(errno, system_category());
+ uint64_t FileSize = FileInfo.st_size;
+
+ if (Size == 0)
+ Size = FileSize;
+ else if (FileSize < Size) {
+ // We need to grow the file.
+ if (ftruncate(fd, Size) == -1)
+ return error_code(errno, system_category());
+ }
+
+ int flags = (Mode == readwrite) ? MAP_SHARED : MAP_PRIVATE;
+ int prot = (Mode == readonly) ? PROT_READ : (PROT_READ | PROT_WRITE);
+#ifdef MAP_FILE
+ flags |= MAP_FILE;
+#endif
+ Mapping = ::mmap(0, Size, prot, flags, fd, offset);
+ if (Mapping == MAP_FAILED)
+ return error_code(errno, system_category());
+ return error_code::success();
+}
+
+mapped_file_region::mapped_file_region(const Twine &path,
+ mapmode mode,
+ uint64_t length,
+ uint64_t offset,
+ error_code &ec)
+ : Mode(mode)
+ , Size(length)
+ , Mapping() {
+ // Make sure that the requested size fits within SIZE_T.
+ if (length > std::numeric_limits<size_t>::max()) {
+ ec = make_error_code(errc::invalid_argument);
+ return;
+ }
+
+ SmallString<128> path_storage;
+ StringRef name = path.toNullTerminatedStringRef(path_storage);
+ int oflags = (mode == readonly) ? O_RDONLY : O_RDWR;
+ int ofd = ::open(name.begin(), oflags);
+ if (ofd == -1) {
+ ec = error_code(errno, system_category());
+ return;
+ }
+
+ ec = init(ofd, offset);
+ if (ec)
+ Mapping = 0;
+}
+
+mapped_file_region::mapped_file_region(int fd,
+ mapmode mode,
+ uint64_t length,
+ uint64_t offset,
+ error_code &ec)
+ : Mode(mode)
+ , Size(length)
+ , Mapping() {
+ // Make sure that the requested size fits within SIZE_T.
+ if (length > std::numeric_limits<size_t>::max()) {
+ ec = make_error_code(errc::invalid_argument);
+ return;
+ }
+
+ ec = init(fd, offset);
+ if (ec)
+ Mapping = 0;
+}
+
+mapped_file_region::~mapped_file_region() {
+ if (Mapping)
+ ::munmap(Mapping, Size);
+}
+
+#ifdef LLVM_USE_RVALUE_REFERENCES
+mapped_file_region::mapped_file_region(mapped_file_region &&other)
+ : Mode(other.Mode), Size(other.Size), Mapping(other.Mapping) {
+ other.Mapping = 0;
+}
+#endif
+
+mapped_file_region::mapmode mapped_file_region::flags() const {
+ assert(Mapping && "Mapping failed but used anyway!");
+ return Mode;
+}
+
+uint64_t mapped_file_region::size() const {
+ assert(Mapping && "Mapping failed but used anyway!");
+ return Size;
+}
+
+char *mapped_file_region::data() const {
+ assert(Mapping && "Mapping failed but used anyway!");
+ assert(Mode != readonly && "Cannot get non const data for readonly mapping!");
+ return reinterpret_cast<char*>(Mapping);
+}
+
+const char *mapped_file_region::const_data() const {
+ assert(Mapping && "Mapping failed but used anyway!");
+ return reinterpret_cast<const char*>(Mapping);
+}
+
+int mapped_file_region::alignment() {
+ return Process::GetPageSize();
+}
+
error_code detail::directory_iterator_construct(detail::DirIterState &it,
StringRef path){
SmallString<128> path_null(path);