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[oota-llvm.git] / lib / Support / MemoryBuffer.cpp

diff --git a/lib/Support/MemoryBuffer.cpp b/lib/Support/MemoryBuffer.cpp
index 0e857021a486915304e68ddde5a22de6ac5ad6f7..4d26d38731a8078b65a3e763207a1fb0389125e3 100644 (file)
--- a/lib/Support/MemoryBuffer.cpp
+++ b/lib/Support/MemoryBuffer.cpp
@@ -2,8 +2,8 @@
 //
 //                     The LLVM Compiler Infrastructure
 //
-// This file was developed by Chris Lattner and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
@@ -59,9 +59,13 @@ namespace {
 class MemoryBufferMem : public MemoryBuffer {
   std::string FileID;
 public:
-  MemoryBufferMem(const char *Start, const char *End, const char *FID)
+  MemoryBufferMem(const char *Start, const char *End, const char *FID,
+                  bool Copy = false)
   : FileID(FID) {
-    init(Start, End);
+    if (!Copy)
+      init(Start, End);
+    else
+      initCopyOf(Start, End);
   }
   
   virtual const char *getBufferIdentifier() const {
@@ -78,6 +82,15 @@ MemoryBuffer *MemoryBuffer::getMemBuffer(const char *StartPtr,
   return new MemoryBufferMem(StartPtr, EndPtr, BufferName);
 }
 
+/// getMemBufferCopy - Open the specified memory range as a MemoryBuffer,
+/// copying the contents and taking ownership of it.  This has no requirements
+/// on EndPtr[0].
+MemoryBuffer *MemoryBuffer::getMemBufferCopy(const char *StartPtr, 
+                                             const char *EndPtr,
+                                             const char *BufferName) {
+  return new MemoryBufferMem(StartPtr, EndPtr, BufferName, true);
+}
+
 /// getNewUninitMemBuffer - Allocate a new MemoryBuffer of the specified size
 /// that is completely initialized to zeros.  Note that the caller should
 /// initialize the memory allocated by this method.  The memory is owned by
@@ -104,6 +117,24 @@ MemoryBuffer *MemoryBuffer::getNewMemBuffer(unsigned Size,
 }
 
 
+/// getFileOrSTDIN - Open the specified file as a MemoryBuffer, or open stdin
+/// if the Filename is "-".  If an error occurs, this returns null and fills
+/// in *ErrStr with a reason.  If stdin is empty, this API (unlike getSTDIN)
+/// returns an empty buffer.
+MemoryBuffer *MemoryBuffer::getFileOrSTDIN(const char *FilenameStart,
+                                           unsigned FnSize,
+                                           std::string *ErrStr,
+                                           int64_t FileSize) {
+  if (FnSize != 1 || FilenameStart[0] != '-')
+    return getFile(FilenameStart, FnSize, ErrStr, FileSize);
+  MemoryBuffer *M = getSTDIN();
+  if (M) return M;
+
+  // If stdin was empty, M is null.  Cons up an empty memory buffer now.
+  const char *EmptyStr = "";
+  return MemoryBuffer::getMemBuffer(EmptyStr, EmptyStr, "<stdin>");
+}
+
 //===----------------------------------------------------------------------===//
 // MemoryBufferMMapFile implementation.
 //===----------------------------------------------------------------------===//
@@ -248,11 +279,14 @@ MemoryBuffer *MemoryBuffer::getSTDIN() {
   
   // Read in all of the data from stdin, we cannot mmap stdin.
   sys::Program::ChangeStdinToBinary();
-  while (size_t ReadBytes = fread(Buffer, 1, 4096*4, stdin))
+  while (size_t ReadBytes = fread(Buffer, sizeof(char), 4096*4, stdin))
     FileData.insert(FileData.end(), Buffer, Buffer+ReadBytes);
-  
+
+  FileData.push_back(0); // &FileData[Size] is invalid. So is &*FileData.end().
   size_t Size = FileData.size();
+  if (Size <= 1)
+    return 0;
   MemoryBuffer *B = new STDINBufferFile();
-  B->initCopyOf(&FileData[0], &FileData[Size]);
+  B->initCopyOf(&FileData[0], &FileData[Size-1]);
   return B;
 }