1 files changed, 82 insertions, 0 deletions
diff --git a/lib/Debugger/SourceFile.cpp b/lib/Debugger/SourceFile.cpp
new file mode 100644
index 0000000..03c60f8
--- /dev/null
+++ b/lib/Debugger/SourceFile.cpp
@@ -0,0 +1,82 @@
+//===-- SourceFile.cpp - SourceFile implementation for the debugger -------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the SourceFile class for the LLVM debugger.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Debugger/SourceFile.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include <cassert>
+using namespace llvm;
+
+static const char EmptyFile = 0;
+
+SourceFile::SourceFile(const std::string &fn, const GlobalVariable *Desc)
+  : Filename(fn), Descriptor(Desc) {
+  File.reset(MemoryBuffer::getFileOrSTDIN(fn));
+    
+  // On error, return an empty buffer.
+  if (File == 0)
+    File.reset(MemoryBuffer::getMemBuffer(&EmptyFile, &EmptyFile));
+}
+
+SourceFile::~SourceFile() {
+}
+
+
+/// calculateLineOffsets - Compute the LineOffset vector for the current file.
+///
+void SourceFile::calculateLineOffsets() const {
+  assert(LineOffset.empty() && "Line offsets already computed!");
+  const char *BufPtr = File->getBufferStart();
+  const char *FileStart = BufPtr;
+  const char *FileEnd = File->getBufferEnd();
+  do {
+    LineOffset.push_back(BufPtr-FileStart);
+
+    // Scan until we get to a newline.
+    while (BufPtr != FileEnd && *BufPtr != '\n' && *BufPtr != '\r')
+      ++BufPtr;
+
+    if (BufPtr != FileEnd) {
+      ++BufPtr;               // Skip over the \n or \r
+      if (BufPtr[-1] == '\r' && BufPtr != FileEnd && BufPtr[0] == '\n')
+        ++BufPtr;   // Skip over dos/windows style \r\n's
+    }
+  } while (BufPtr != FileEnd);
+}
+
+
+/// getSourceLine - Given a line number, return the start and end of the line
+/// in the file.  If the line number is invalid, or if the file could not be
+/// loaded, null pointers are returned for the start and end of the file. Note
+/// that line numbers start with 0, not 1.
+void SourceFile::getSourceLine(unsigned LineNo, const char *&LineStart,
+                               const char *&LineEnd) const {
+  LineStart = LineEnd = 0;
+  if (LineOffset.empty()) calculateLineOffsets();
+
+  // Asking for an out-of-range line number?
+  if (LineNo >= LineOffset.size()) return;
+
+  // Otherwise, they are asking for a valid line, which we can fulfill.
+  LineStart = File->getBufferStart()+LineOffset[LineNo];
+
+  if (LineNo+1 < LineOffset.size())
+    LineEnd = File->getBufferStart()+LineOffset[LineNo+1];
+  else
+    LineEnd = File->getBufferEnd();
+
+  // If the line ended with a newline, strip it off.
+  while (LineEnd != LineStart && (LineEnd[-1] == '\n' || LineEnd[-1] == '\r'))
+    --LineEnd;
+
+  assert(LineEnd >= LineStart && "We somehow got our pointers swizzled!");
+}