#ifndef LLVM_ADT_STRINGREF_H
#define LLVM_ADT_STRINGREF_H
+#include "llvm/Support/type_traits.h"
+
+#include <algorithm>
#include <cassert>
#include <cstring>
-#include <utility>
+#include <limits>
#include <string>
+#include <utility>
namespace llvm {
template<typename T>
class SmallVectorImpl;
class APInt;
+ class hash_code;
+ class StringRef;
+
+ /// Helper functions for StringRef::getAsInteger.
+ bool getAsUnsignedInteger(StringRef Str, unsigned Radix,
+ unsigned long long &Result);
+
+ bool getAsSignedInteger(StringRef Str, unsigned Radix, long long &Result);
/// StringRef - Represent a constant reference to a string, i.e. a character
/// array and a length, which need not be null terminated.
// integer works around this bug.
static size_t min(size_t a, size_t b) { return a < b ? a : b; }
static size_t max(size_t a, size_t b) { return a > b ? a : b; }
-
+
+ // Workaround memcmp issue with null pointers (undefined behavior)
+ // by providing a specialized version
+ static int compareMemory(const char *Lhs, const char *Rhs, size_t Length) {
+ if (Length == 0) { return 0; }
+ return ::memcmp(Lhs,Rhs,Length);
+ }
+
public:
/// @name Constructors
/// @{
/// Construct a string ref from a cstring.
/*implicit*/ StringRef(const char *Str)
- : Data(Str), Length(::strlen(Str)) {}
+ : Data(Str) {
+ assert(Str && "StringRef cannot be built from a NULL argument");
+ Length = ::strlen(Str); // invoking strlen(NULL) is undefined behavior
+ }
/// Construct a string ref from a pointer and length.
/*implicit*/ StringRef(const char *data, size_t length)
- : Data(data), Length(length) {}
+ : Data(data), Length(length) {
+ assert((data || length == 0) &&
+ "StringRef cannot be built from a NULL argument with non-null length");
+ }
/// Construct a string ref from an std::string.
/*implicit*/ StringRef(const std::string &Str)
/// compare() when the relative ordering of inequal strings isn't needed.
bool equals(StringRef RHS) const {
return (Length == RHS.Length &&
- memcmp(Data, RHS.Data, RHS.Length) == 0);
+ compareMemory(Data, RHS.Data, RHS.Length) == 0);
}
/// equals_lower - Check for string equality, ignoring case.
/// is lexicographically less than, equal to, or greater than the \arg RHS.
int compare(StringRef RHS) const {
// Check the prefix for a mismatch.
- if (int Res = memcmp(Data, RHS.Data, min(Length, RHS.Length)))
+ if (int Res = compareMemory(Data, RHS.Data, min(Length, RHS.Length)))
return Res < 0 ? -1 : 1;
// Otherwise the prefixes match, so we only need to check the lengths.
/// startswith - Check if this string starts with the given \arg Prefix.
bool startswith(StringRef Prefix) const {
return Length >= Prefix.Length &&
- memcmp(Data, Prefix.Data, Prefix.Length) == 0;
+ compareMemory(Data, Prefix.Data, Prefix.Length) == 0;
}
/// endswith - Check if this string ends with the given \arg Suffix.
bool endswith(StringRef Suffix) const {
return Length >= Suffix.Length &&
- memcmp(end() - Suffix.Length, Suffix.Data, Suffix.Length) == 0;
+ compareMemory(end() - Suffix.Length, Suffix.Data, Suffix.Length) == 0;
}
/// @}
/// Note: O(size() + Chars.size())
size_type find_first_not_of(StringRef Chars, size_t From = 0) const;
+ /// find_last_of - Find the last character in the string that is \arg C, or
+ /// npos if not found.
+ size_type find_last_of(char C, size_t From = npos) const {
+ return rfind(C, From);
+ }
+
+ /// find_last_of - Find the last character in the string that is in \arg C,
+ /// or npos if not found.
+ ///
+ /// Note: O(size() + Chars.size())
+ size_type find_last_of(StringRef Chars, size_t From = npos) const;
+
+ /// find_last_not_of - Find the last character in the string that is not
+ /// \arg C, or npos if not found.
+ size_type find_last_not_of(char C, size_t From = npos) const;
+
+ /// find_last_not_of - Find the last character in the string that is not in
+ /// \arg Chars, or npos if not found.
+ ///
+ /// Note: O(size() + Chars.size())
+ size_type find_last_not_of(StringRef Chars, size_t From = npos) const;
+
/// @}
/// @name Helpful Algorithms
/// @{
///
/// If the string is invalid or if only a subset of the string is valid,
/// this returns true to signify the error. The string is considered
- /// erroneous if empty.
+ /// erroneous if empty or if it overflows T.
///
- bool getAsInteger(unsigned Radix, long long &Result) const;
- bool getAsInteger(unsigned Radix, unsigned long long &Result) const;
- bool getAsInteger(unsigned Radix, int &Result) const;
- bool getAsInteger(unsigned Radix, unsigned &Result) const;
+ template <typename T>
+ typename enable_if_c<std::numeric_limits<T>::is_signed, bool>::type
+ getAsInteger(unsigned Radix, T &Result) const {
+ long long LLVal;
+ if (getAsSignedInteger(*this, Radix, LLVal) ||
+ static_cast<T>(LLVal) != LLVal)
+ return true;
+ Result = LLVal;
+ return false;
+ }
- // TODO: Provide overloads for int/unsigned that check for overflow.
+ template <typename T>
+ typename enable_if_c<!std::numeric_limits<T>::is_signed, bool>::type
+ getAsInteger(unsigned Radix, T &Result) const {
+ unsigned long long ULLVal;
+ if (getAsUnsignedInteger(*this, Radix, ULLVal) ||
+ static_cast<T>(ULLVal) != ULLVal)
+ return true;
+ Result = ULLVal;
+ return false;
+ }
/// getAsInteger - Parse the current string as an integer of the
/// specified radix, or of an autosensed radix if the radix given
/// string is well-formed in the given radix.
bool getAsInteger(unsigned Radix, APInt &Result) const;
+ /// @}
+ /// @name String Operations
+ /// @{
+
+ // lower - Convert the given ASCII string to lowercase.
+ std::string lower() const;
+
+ /// upper - Convert the given ASCII string to uppercase.
+ std::string upper() const;
+
/// @}
/// @name Substring Operations
/// @{
Start = min(Start, Length);
return StringRef(Data + Start, min(N, Length - Start));
}
+
+ /// drop_front - Return a StringRef equal to 'this' but with the first
+ /// elements dropped.
+ StringRef drop_front(unsigned N = 1) const {
+ assert(size() >= N && "Dropping more elements than exist");
+ return substr(N);
+ }
+
+ /// drop_back - Return a StringRef equal to 'this' but with the last
+ /// elements dropped.
+ StringRef drop_back(unsigned N = 1) const {
+ assert(size() >= N && "Dropping more elements than exist");
+ return substr(0, size()-N);
+ }
/// slice - Return a reference to the substring from [Start, End).
///
return std::make_pair(slice(0, Idx), slice(Idx+1, npos));
}
+ /// ltrim - Return string with consecutive characters in \arg Chars starting
+ /// from the left removed.
+ StringRef ltrim(StringRef Chars = " \t\n\v\f\r") const {
+ return drop_front(std::min(Length, find_first_not_of(Chars)));
+ }
+
+ /// rtrim - Return string with consecutive characters in \arg Chars starting
+ /// from the right removed.
+ StringRef rtrim(StringRef Chars = " \t\n\v\f\r") const {
+ return drop_back(Length - std::min(Length, find_last_not_of(Chars) + 1));
+ }
+
+ /// trim - Return string with consecutive characters in \arg Chars starting
+ /// from the left and right removed.
+ StringRef trim(StringRef Chars = " \t\n\v\f\r") const {
+ return ltrim(Chars).rtrim(Chars);
+ }
+
/// @}
};
return LHS.compare(RHS) != -1;
}
+ inline std::string &operator+=(std::string &buffer, llvm::StringRef string) {
+ return buffer.append(string.data(), string.size());
+ }
+
/// @}
+ /// \brief Compute a hash_code for a StringRef.
+ hash_code hash_value(StringRef S);
+
+ // StringRefs can be treated like a POD type.
+ template <typename T> struct isPodLike;
+ template <> struct isPodLike<StringRef> { static const bool value = true; };
+
}
#endif