folly/wangle -> wangle cutover

[folly.git] / folly / String.h

diff --git a/folly/String.h b/folly/String.h
index 223c49073ca6be1278a67cde04d565921c0258c4..04004b56f510042c62ff7edbf094d5f0692c3abc 100644 (file)
--- a/folly/String.h
+++ b/folly/String.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2014 Facebook, Inc.
+ * Copyright 2015 Facebook, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -18,6 +18,7 @@
 #define FOLLY_BASE_STRING_H_
 
 #include <exception>
+#include <stdarg.h>
 #include <string>
 #include <boost/type_traits.hpp>
 
@@ -186,6 +187,16 @@ std::string& stringAppendf(std::string* output,
                           FOLLY_PRINTF_FORMAT const char* format, ...)
   FOLLY_PRINTF_FORMAT_ATTR(2, 3);
 
+/**
+ * Similar to stringPrintf, but accepts a va_list argument.
+ *
+ * As with vsnprintf() itself, the value of ap is undefined after the call.
+ * These functions do not call va_end() on ap.
+ */
+std::string stringVPrintf(const char* format, va_list ap);
+void stringVPrintf(std::string* out, const char* format, va_list ap);
+std::string& stringVAppendf(std::string* out, const char* format, va_list ap);
+
 /**
  * Backslashify a string, that is, replace non-printable characters
  * with C-style (but NOT C compliant) "\xHH" encoding.  If hex_style
@@ -349,19 +360,21 @@ std::string hexDump(const void* ptr, size_t size);
 fbstring errnoStr(int err);
 
 /**
- * Debug string for an exception: include type and what().  Note that
- * the non-templated function overloads will be used in preference to
- * the template.
+ * Debug string for an exception: include type and what(), if
+ * defined.
  */
-template<typename T>
-fbstring exceptionStr(const T& e) {
-  return folly::to<fbstring>(demangle(typeid(e)));
-}
-
 inline fbstring exceptionStr(const std::exception& e) {
+#ifdef FOLLY_HAS_RTTI
   return folly::to<fbstring>(demangle(typeid(e)), ": ", e.what());
+#else
+  return folly::to<fbstring>("Exception (no RTTI available): ", e.what());
+#endif
 }
 
+// Empirically, this indicates if the runtime supports
+// std::exception_ptr, as not all (arm, for instance) do.
+#if defined(__GNUC__) && defined(__GCC_ATOMIC_INT_LOCK_FREE) && \
+  __GCC_ATOMIC_INT_LOCK_FREE > 1
 inline fbstring exceptionStr(std::exception_ptr ep) {
   try {
     std::rethrow_exception(ep);
@@ -371,6 +384,19 @@ inline fbstring exceptionStr(std::exception_ptr ep) {
     return "<unknown exception>";
   }
 }
+#endif
+
+template<typename E>
+auto exceptionStr(const E& e)
+  -> typename std::enable_if<!std::is_base_of<std::exception, E>::value,
+                             fbstring>::type
+{
+#ifdef FOLLY_HAS_RTTI
+  return folly::to<fbstring>(demangle(typeid(e)));
+#else
+  return "Exception (no RTTI available)";
+#endif
+}
 
 /*
  * Split a string into a list of tokens by delimiter.
@@ -424,7 +450,9 @@ void splitTo(const Delim& delimiter,
  * Split a string into a fixed number of string pieces and/or numeric types
  * by delimiter. Any numeric type that folly::to<> can convert to from a
  * string piece is supported as a target. Returns 'true' if the fields were
- * all successfully populated.
+ * all successfully populated.  Returns 'false' if there were too few fields
+ * in the input, or too many fields if exact=true.  Casting exceptions will
+ * not be caught.
  *
  * Examples:
  *
@@ -511,11 +539,45 @@ std::string join(const Delim& delimiter,
   return output;
 }
 
+template <class Delim,
+          class Iterator,
+          typename std::enable_if<std::is_same<
+              typename std::iterator_traits<Iterator>::iterator_category,
+              std::random_access_iterator_tag>::value>::type* = nullptr>
+std::string join(const Delim& delimiter, Iterator begin, Iterator end) {
+  std::string output;
+  join(delimiter, begin, end, output);
+  return output;
+}
+
+/**
+ * Returns a subpiece with all whitespace removed from the front of @sp.
+ * Whitespace means any of [' ', '\n', '\r', '\t'].
+ */
+StringPiece ltrimWhitespace(StringPiece sp);
+
+/**
+ * Returns a subpiece with all whitespace removed from the back of @sp.
+ * Whitespace means any of [' ', '\n', '\r', '\t'].
+ */
+StringPiece rtrimWhitespace(StringPiece sp);
+
+/**
+ * Returns a subpiece with all whitespace removed from the back and front of @sp.
+ * Whitespace means any of [' ', '\n', '\r', '\t'].
+ */
+inline StringPiece trimWhitespace(StringPiece sp) {
+  return ltrimWhitespace(rtrimWhitespace(sp));
+}
+
 /**
  * Returns a subpiece with all whitespace removed from the front of @sp.
  * Whitespace means any of [' ', '\n', '\r', '\t'].
+ * DEPRECATED: @see ltrimWhitespace @see rtrimWhitespace
  */
-StringPiece skipWhitespace(StringPiece sp);
+inline StringPiece skipWhitespace(StringPiece sp) {
+  return ltrimWhitespace(sp);
+}
 
 /**
  * Fast, in-place lowercasing of ASCII alphabetic characters in strings.