Add StringPrintV, fix libxml_utils.cc to use it

Review URL: http://codereview.chromium.org/464064

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@34029 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 9 insertions, 0 deletions

diff --git a/base/string_util.cc b/base/string_util.cc
index 9db0f03..b38e182 100644
--- a/base/string_util.cc
+++ b/base/string_util.cc
@@ -1245,6 +1245,12 @@ std::wstring StringPrintf(const wchar_t* format, ...) {
   return result;
 }
 
+std::string StringPrintV(const char* format, va_list ap) {
+  std::string result;
+  StringAppendV(&result, format, ap);
+  return result;
+}
+
 const std::string& SStringPrintf(std::string* dst, const char* format, ...) {
   va_list ap;
   va_start(ap, format);
diff --git a/base/string_util.h b/base/string_util.h
index 66518e9..723242e 100644
--- a/base/string_util.h
+++ b/base/string_util.h
@@ -453,6 +453,9 @@ double StringToDouble(const string16& value);
 std::string StringPrintf(const char* format, ...) PRINTF_FORMAT(1, 2);
 std::wstring StringPrintf(const wchar_t* format, ...) WPRINTF_FORMAT(1, 2);
 
+// Return a C++ string given vprintf-like input.
+std::string StringPrintV(const char* format, va_list ap) PRINTF_FORMAT(1, 0);
+
 // Store result into a supplied string and return it
 const std::string& SStringPrintf(std::string* dst, const char* format, ...)
     PRINTF_FORMAT(2, 3);