vendor/lld/lld-trunk-r233088

1 files changed, 118 insertions, 0 deletions

diff --git a/lib/ReaderWriter/PECOFF/WriterImportLibrary.cpp b/lib/ReaderWriter/PECOFF/WriterImportLibrary.cpp
new file mode 100644
index 0000000000000..fd3360f018b6d
--- /dev/null
+++ b/lib/ReaderWriter/PECOFF/WriterImportLibrary.cpp
@@ -0,0 +1,118 @@
+//===- lib/ReaderWriter/PECOFF/WriterImportLibrary.cpp --------------------===//
+//
+//                             The LLVM Linker
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// This file is responsible for creating the Import Library file.
+///
+//===----------------------------------------------------------------------===//
+
+#include "lld/ReaderWriter/PECOFFLinkingContext.h"
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/FileUtilities.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/Program.h"
+#include "llvm/Support/raw_ostream.h"
+
+namespace lld {
+namespace pecoff {
+
+/// Creates a .def file containing the list of exported symbols.
+static std::string
+createModuleDefinitionFile(const PECOFFLinkingContext &ctx) {
+  std::string ret;
+  llvm::raw_string_ostream os(ret);
+  os << "LIBRARY \"" << llvm::sys::path::filename(ctx.outputPath()) << "\"\n"
+     << "EXPORTS\n";
+
+  for (const PECOFFLinkingContext::ExportDesc &desc : ctx.getDllExports()) {
+    // Symbol names in a module-definition file will be mangled by lib.exe,
+    // so we need to demangle them before writing to a .def file.
+    os << "  ";
+    if (!desc.externalName.empty()) {
+      os << desc.externalName;
+    } else if (!desc.mangledName.empty()) {
+      os << ctx.undecorateSymbol(desc.mangledName);
+    } else {
+      os << ctx.undecorateSymbol(desc.name);
+    }
+
+    if (!desc.isPrivate)
+      os << " @" << desc.ordinal;
+    if (desc.noname)
+      os << " NONAME";
+    if (desc.isData)
+      os << " DATA";
+    if (desc.isPrivate)
+      os << " PRIVATE";
+    os << "\n";
+  }
+  os.flush();
+  return ret;
+}
+
+static std::string writeToTempFile(StringRef contents) {
+  SmallString<128> path;
+  int fd;
+  if (llvm::sys::fs::createTemporaryFile("tmp", "def", fd, path)) {
+    llvm::errs() << "Failed to create temporary file\n";
+    return "";
+  }
+  llvm::raw_fd_ostream os(fd, /*shouldClose*/ true);
+  os << contents;
+  return path.str();
+}
+
+static void writeTo(StringRef path, StringRef contents) {
+  int fd;
+  if (llvm::sys::fs::openFileForWrite(path, fd, llvm::sys::fs::F_Text)) {
+    llvm::errs() << "Failed to open " << path << "\n";
+    return;
+  }
+  llvm::raw_fd_ostream os(fd, /*shouldClose*/ true);
+  os << contents;
+}
+
+/// Creates a .def file and runs lib.exe on it to create an import library.
+void writeImportLibrary(const PECOFFLinkingContext &ctx) {
+  std::string fileContents = createModuleDefinitionFile(ctx);
+
+  std::string program = "lib.exe";
+  ErrorOr<std::string> programPathOrErr = llvm::sys::findProgramByName(program);
+  if (!programPathOrErr) {
+    llvm::errs() << "Unable to find " << program << " in PATH\n";
+  } else {
+    const std::string &programPath = *programPathOrErr;
+
+    std::string defPath = writeToTempFile(fileContents);
+    llvm::FileRemover tmpFile(defPath);
+
+    std::string defArg = "/def:";
+    defArg.append(defPath);
+    std::string outputArg = "/out:";
+    outputArg.append(ctx.getOutputImportLibraryPath());
+
+    std::vector<const char *> args;
+    args.push_back(programPath.c_str());
+    args.push_back("/nologo");
+    args.push_back(ctx.is64Bit() ? "/machine:x64" : "/machine:x86");
+    args.push_back(defArg.c_str());
+    args.push_back(outputArg.c_str());
+    args.push_back(nullptr);
+
+    if (llvm::sys::ExecuteAndWait(programPath.c_str(), &args[0]) != 0)
+      llvm::errs() << program << " failed\n";
+  }
+
+  // If /lldmoduledeffile:<filename> is given, make a copy of the
+  // temporary module definition file. This feature is for unit tests.
+  if (!ctx.getModuleDefinitionFile().empty())
+    writeTo(ctx.getModuleDefinitionFile(), fileContents);
+}
+
+} // end namespace pecoff
+} // end namespace lld