Add SmallString a (currently) minimal class that adapts SmallVector to be

more string-like.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31289 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/ADT/SmallString.h

@@ -0,0 +1,57 @@
+//===- llvm/ADT/SmallString.h - 'Normally small' strings --------*- C++ -*-===//
+//
+//                     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 defines the SmallString class.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_ADT_SMALLSTRING_H
+#define LLVM_ADT_SMALLSTRING_H
+
+#include "llvm/ADT/SmallVector.h"
+#include <cstring>
+
+namespace llvm {
+
+/// SmallString - A SmallString is just a SmallVector with methods and accessors
+/// that make it work better as a string (e.g. operator+ etc).
+template<unsigned InternalLen>
+class SmallString : public SmallVector<char, InternalLen> {
+public:
+  // Default ctor - Initialize to empty.
+  SmallString() {}
+
+  // Initialize with a range.
+  template<typename ItTy>
+  SmallString(ItTy S, ItTy E) : SmallVector<char, InternalLen>(S, E) {}
+  
+  // Copy ctor.
+  SmallString(const SmallString &RHS) : SmallVector<char, InternalLen>(RHS) {}
+
+  
+  // Extra methods.
+  const char *c_str() const {
+    SmallString *This = const_cast<SmallString*>(this);
+    // Ensure that there is a \0 at the end of the string.
+    This->reserve(this->size()+1);
+    This->End[0] = 0;
+    return this->begin();
+  }
+  
+  // Extra operators.
+  SmallString &operator+=(const char *RHS) {
+    this->append(RHS, RHS+strlen(RHS));
+    return *this;
+  }
+};
+  
+  
+}
+
+#endif

include/llvm/ADT/SmallVector.h

@@ -25,6 +25,7 @@ namespace llvm {
 /// template parameter.
 template <typename T>
 class SmallVectorImpl {
+protected:
   T *Begin, *End, *Capacity;
   
   // Allocate raw space for N elements of type T.  If T has a ctor or dtor, we