Initial Checkin of gccld

[oota-llvm.git] / tools / llvm-link / llvm-link.cpp

diff --git a/tools/llvm-link/llvm-link.cpp b/tools/llvm-link/llvm-link.cpp
index 9bf766fcaad66c3cbf388c36d2b4c81dcf509c06..4f7530ced3e4e7f84305ef3cd56bcd483a670dde 100644 (file)
--- a/tools/llvm-link/llvm-link.cpp
+++ b/tools/llvm-link/llvm-link.cpp
@@ -18,6 +18,8 @@
 #include "Support/CommandLine.h"
 #include <fstream>
 #include <memory>
+#include <sys/types.h>     // For FileExists
+#include <sys/stat.h>
 
 
 cl::StringList InputFilenames("", "Load <arg> files, linking them together", 
@@ -28,14 +30,26 @@ cl::Flag   Verbose       ("v", "Print information about actions taken");
 cl::Flag   DumpAsm       ("d", "Print assembly as linked", cl::Hidden, false);
 cl::StringList LibPaths  ("L", "Specify a library search path", cl::ZeroOrMore);
 
-static inline std::auto_ptr<Module> LoadFile(const string &FN) {
-  string Filename = FN;
-  string ErrorMessage;
+
+// FileExists - Return true if the specified string is an openable file...
+static inline bool FileExists(const std::string &FN) {
+  struct stat StatBuf;
+  return stat(FN.c_str(), &StatBuf) != -1;
+}
+
+// LoadFile - Read the specified bytecode file in and return it.  This routine
+// searches the link path for the specified file to try to find it...
+//
+static inline std::auto_ptr<Module> LoadFile(const std::string &FN) {
+  std::string Filename = FN;
+  std::string ErrorMessage;
 
   unsigned NextLibPathIdx = 0;
+  bool FoundAFile = false;
 
   while (1) {
     if (Verbose) cerr << "Loading '" << Filename << "'\n";
+    if (FileExists(Filename)) FoundAFile = true;
     Module *Result = ParseBytecodeFile(Filename, &ErrorMessage);
     if (Result) return std::auto_ptr<Module>(Result);   // Load successful!
 
@@ -49,10 +63,17 @@ static inline std::auto_ptr<Module> LoadFile(const string &FN) {
     Filename = LibPaths[NextLibPathIdx++] + "/" + FN;
   }
 
-  cerr << "Could not locate bytecode file: '" << FN << "'\n";
+  if (FoundAFile)
+    cerr << "Bytecode file '" << FN << "' corrupt!  "
+         << "Use 'link -v ...' for more info.\n";
+  else
+    cerr << "Could not locate bytecode file: '" << FN << "'\n";
   return std::auto_ptr<Module>();
 }
 
+
+
+
 int main(int argc, char **argv) {
   cl::ParseCommandLineOptions(argc, argv, " llvm linker\n",
                              cl::EnableSingleLetterArgValue |
@@ -60,7 +81,7 @@ int main(int argc, char **argv) {
   assert(InputFilenames.size() > 0 && "OneOrMore is not working");
 
   unsigned BaseArg = 0;
-  string ErrorMessage;
+  std::string ErrorMessage;
 
   // TODO: TEST argv[0] for llvm-ar forms... for now, this is a huge hack.
   if (InputFilenames.size() >= 3 && InputFilenames[0] == "rc" &&
@@ -73,7 +94,7 @@ int main(int argc, char **argv) {
   if (Composite.get() == 0) return 1;
 
   for (unsigned i = BaseArg+1; i < InputFilenames.size(); ++i) {
-    auto_ptr<Module> M(LoadFile(InputFilenames[i]));
+    std::auto_ptr<Module> M(LoadFile(InputFilenames[i]));
     if (M.get() == 0) return 1;
 
     if (Verbose) cerr << "Linking in '" << InputFilenames[i] << "'\n";
@@ -90,8 +111,13 @@ int main(int argc, char **argv) {
 
   ostream *Out = &cout;  // Default to printing to stdout...
   if (OutputFilename != "-") {
-    Out = new ofstream(OutputFilename.c_str(), 
-                      (Force ? 0 : ios::noreplace)|ios::out);
+    if (!Force && std::ifstream(OutputFilename.c_str())) {
+      // If force is not specified, make sure not to overwrite a file!
+      cerr << "Error opening '" << OutputFilename << "': File exists!\n"
+           << "Use -f command line argument to force output\n";
+      return 1;
+    }
+    Out = new std::ofstream(OutputFilename.c_str());
     if (!Out->good()) {
       cerr << "Error opening '" << OutputFilename << "'!\n";
       return 1;
@@ -101,6 +127,6 @@ int main(int argc, char **argv) {
   if (Verbose) cerr << "Writing bytecode...\n";
   WriteBytecodeToFile(Composite.get(), *Out);
 
-  if (Out != &cout) delete Out;
+  if (Out != &std::cout) delete Out;
   return 0;
 }