[llvm-commits] [llvm] r120600 - in /llvm/trunk: include/llvm/ADT/Twine.h lib/Support/Twine.cpp unittests/ADT/TwineTest.cpp

[Michael J. Spencer]

Author: mspencer
Date: Wed Dec  1 14:37:30 2010
New Revision: 120600

URL: http://llvm.org/viewvc/llvm-project?rev=120600&view=rev
Log:
Support/ADT/Twine: Add toNullTerminatedStringRef.

Modified:
    llvm/trunk/include/llvm/ADT/Twine.h
    llvm/trunk/lib/Support/Twine.cpp
    llvm/trunk/unittests/ADT/TwineTest.cpp

Modified: llvm/trunk/include/llvm/ADT/Twine.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/ADT/Twine.h?rev=120600&r1=120599&r2=120600&view=diff
==============================================================================
--- llvm/trunk/include/llvm/ADT/Twine.h (original)
+++ llvm/trunk/include/llvm/ADT/Twine.h Wed Dec  1 14:37:30 2010
@@ -382,6 +382,14 @@
     /// SmallVector and a StringRef to the SmallVector's data is returned.
     StringRef toStringRef(SmallVectorImpl<char> &Out) const;
 
+    /// toNullTerminatedStringRef - This returns the twine as a single null
+    /// terminated StringRef if it can be represented as such. Otherwise the
+    /// twine is written into the given SmallVector and a StringRef to the
+    /// SmallVector's data is returned.
+    ///
+    /// The returned StringRef's size does not include the null terminator.
+    StringRef toNullTerminatedStringRef(SmallVectorImpl<char> &Out) const;
+
     /// print - Write the concatenated string represented by this twine to the
     /// stream \arg OS.
     void print(raw_ostream &OS) const;

Modified: llvm/trunk/lib/Support/Twine.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Support/Twine.cpp?rev=120600&r1=120599&r2=120600&view=diff
==============================================================================
--- llvm/trunk/lib/Support/Twine.cpp (original)
+++ llvm/trunk/lib/Support/Twine.cpp Wed Dec  1 14:37:30 2010
@@ -30,6 +30,18 @@
   return StringRef(Out.data(), Out.size());
 }
 
+StringRef Twine::toNullTerminatedStringRef(SmallVectorImpl<char> &Out) const {
+  if (isSingleStringRef()) {
+    StringRef sr = getSingleStringRef();
+    if (*(sr.begin() + sr.size()) == 0)
+      return sr;
+  }
+  toVector(Out);
+  Out.push_back(0);
+  Out.pop_back();
+  return StringRef(Out.data(), Out.size());
+}
+
 void Twine::printOneChild(raw_ostream &OS, const void *Ptr,
                           NodeKind Kind) const {
   switch (Kind) {

Modified: llvm/trunk/unittests/ADT/TwineTest.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/unittests/ADT/TwineTest.cpp?rev=120600&r1=120599&r2=120600&view=diff
==============================================================================
--- llvm/trunk/unittests/ADT/TwineTest.cpp (original)
+++ llvm/trunk/unittests/ADT/TwineTest.cpp Wed Dec  1 14:37:30 2010
@@ -9,6 +9,7 @@
 
 #include "gtest/gtest.h"
 #include "llvm/ADT/Twine.h"
+#include "llvm/ADT/SmallString.h"
 #include "llvm/Support/raw_ostream.h"
 using namespace llvm;
 
@@ -69,6 +70,13 @@
             repr(Twine("a").concat(Twine("b").concat(Twine("c")))));
 }
 
+TEST(TwineTest, toNullTerminatedStringRef) {
+  SmallString<8> storage;
+  EXPECT_EQ(0, *Twine("hello").toNullTerminatedStringRef(storage).end());
+  EXPECT_EQ(0,
+           *Twine(StringRef("hello")).toNullTerminatedStringRef(storage).end());
+}
+
   // I suppose linking in the entire code generator to add a unit test to check
   // the code size of the concat operation is overkill... :)