Fix five of the shared library build targets

Before this patch there was a cyclic dependency between lldCore and
lldReaderWriter.  Only lldConfig could be built as a shared library.

* Moved Reader and Writer base classes into lldCore.
* The following shared libraries can now be built:
     lldCore
     lldYAML
     lldNative
     lldPasses
     lldReaderWriter

Differential Revision: http://reviews.llvm.org/D7105

From: Greg Fitzgerald <garious@gmail.com>
llvm-svn: 226732

1 files changed, 119 insertions, 0 deletions

diff --git a/lld/lib/Core/Reader.cpp b/lld/lib/Core/Reader.cpp
new file mode 100644
index 00000000000..6027c14ebfe
--- /dev/null
+++ b/lld/lib/Core/Reader.cpp
@@ -0,0 +1,119 @@
+//===- lib/Core/Reader.cpp ------------------------------------------------===//
+//
+//                             The LLVM Linker
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "lld/Core/File.h"
+#include "lld/Core/Reader.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/Errc.h"
+#include "llvm/Support/FileUtilities.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/Path.h"
+#include <memory>
+#include <system_error>
+
+namespace lld {
+
+YamlIOTaggedDocumentHandler::~YamlIOTaggedDocumentHandler() {}
+
+void Registry::add(std::unique_ptr<Reader> reader) {
+  _readers.push_back(std::move(reader));
+}
+
+void Registry::add(std::unique_ptr<YamlIOTaggedDocumentHandler> handler) {
+  _yamlHandlers.push_back(std::move(handler));
+}
+
+std::error_code
+Registry::loadFile(std::unique_ptr<MemoryBuffer> mb,
+                   std::vector<std::unique_ptr<File>> &result) const {
+  // Get file type.
+  StringRef content(mb->getBufferStart(), mb->getBufferSize());
+  llvm::sys::fs::file_magic fileType = llvm::sys::fs::identify_magic(content);
+  // Get file extension.
+  StringRef extension = llvm::sys::path::extension(mb->getBufferIdentifier());
+
+  // Ask each registered reader if it can handle this file type or extension.
+  for (const std::unique_ptr<Reader> &reader : _readers) {
+    if (!reader->canParse(fileType, extension, *mb))
+      continue;
+    if (std::error_code ec = reader->loadFile(std::move(mb), *this, result))
+      return ec;
+    return std::error_code();
+  }
+
+  // No Reader could parse this file.
+  return make_error_code(llvm::errc::executable_format_error);
+}
+
+static const Registry::KindStrings kindStrings[] = {
+    {Reference::kindInGroup, "in-group"},
+    {Reference::kindLayoutAfter, "layout-after"},
+    {Reference::kindLayoutBefore, "layout-before"},
+    {Reference::kindGroupChild, "group-child"},
+    {Reference::kindAssociate, "associate"},
+    LLD_KIND_STRING_END};
+
+Registry::Registry() {
+  addKindTable(Reference::KindNamespace::all, Reference::KindArch::all,
+               kindStrings);
+}
+
+bool Registry::handleTaggedDoc(llvm::yaml::IO &io,
+                               const lld::File *&file) const {
+  for (const std::unique_ptr<YamlIOTaggedDocumentHandler> &h : _yamlHandlers)
+    if (h->handledDocTag(io, file))
+      return true;
+  return false;
+}
+
+
+void Registry::addKindTable(Reference::KindNamespace ns,
+                            Reference::KindArch arch,
+                            const KindStrings array[]) {
+  KindEntry entry = { ns, arch, array };
+  _kindEntries.push_back(entry);
+}
+
+bool Registry::referenceKindFromString(StringRef inputStr,
+                                       Reference::KindNamespace &ns,
+                                       Reference::KindArch &arch,
+                                       Reference::KindValue &value) const {
+  for (const KindEntry &entry : _kindEntries) {
+    for (const KindStrings *pair = entry.array; !pair->name.empty(); ++pair) {
+      if (!inputStr.equals(pair->name))
+        continue;
+      ns = entry.ns;
+      arch = entry.arch;
+      value = pair->value;
+      return true;
+    }
+  }
+  return false;
+}
+
+bool Registry::referenceKindToString(Reference::KindNamespace ns,
+                                     Reference::KindArch arch,
+                                     Reference::KindValue value,
+                                     StringRef &str) const {
+  for (const KindEntry &entry : _kindEntries) {
+    if (entry.ns != ns)
+      continue;
+    if (entry.arch != arch)
+      continue;
+    for (const KindStrings *pair = entry.array; !pair->name.empty(); ++pair) {
+      if (pair->value != value)
+        continue;
+      str = pair->name;
+      return true;
+    }
+  }
+  return false;
+}
+
+} // end namespace lld