name : pcre_stringpiece.h // Copyright (c) 2005, Google Inc. // All rights reserved. // // Redistribution and use in source and binary forms, with or without // modification, are permitted provided that the following conditions are // met: // // * Redistributions of source code must retain the above copyright // notice, this list of conditions and the following disclaimer. // * Redistributions in binary form must reproduce the above // copyright notice, this list of conditions and the following disclaimer // in the documentation and/or other materials provided with the // distribution. // * Neither the name of Google Inc. nor the names of its // contributors may be used to endorse or promote products derived from // this software without specific prior written permission. // // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. // // Author: Sanjay Ghemawat // // A string like object that points into another piece of memory. // Useful for providing an interface that allows clients to easily // pass in either a "const char*" or a "string". // // Arghh! I wish C++ literals were automatically of type "string". #ifndef _PCRE_STRINGPIECE_H #define _PCRE_STRINGPIECE_H #include <cstring> #include <string> #include <iosfwd> // for ostream forward-declaration #if 0 #define HAVE_TYPE_TRAITS #include <type_traits.h> #elif 0 #define HAVE_TYPE_TRAITS #include <bits/type_traits.h> #endif #include <pcre.h> namespace pcrecpp { using std::memcmp; using std::strlen; using std::string; class PCRECPP_EXP_DEFN StringPiece { private: const char* ptr_; int length_; public: // We provide non-explicit singleton constructors so users can pass // in a "const char*" or a "string" wherever a "StringPiece" is // expected. StringPiece() : ptr_(NULL), length_(0) { } StringPiece(const char* str) : ptr_(str), length_(static_cast<int>(strlen(ptr_))) { } StringPiece(const unsigned char* str) : ptr_(reinterpret_cast<const char*>(str)), length_(static_cast<int>(strlen(ptr_))) { } StringPiece(const string& str) : ptr_(str.data()), length_(static_cast<int>(str.size())) { } StringPiece(const char* offset, int len) : ptr_(offset), length_(len) { } // data() may return a pointer to a buffer with embedded NULs, and the // returned buffer may or may not be null terminated. Therefore it is // typically a mistake to pass data() to a routine that expects a NUL // terminated string. Use "as_string().c_str()" if you really need to do // this. Or better yet, change your routine so it does not rely on NUL // termination. const char* data() const { return ptr_; } int size() const { return length_; } bool empty() const { return length_ == 0; } void clear() { ptr_ = NULL; length_ = 0; } void set(const char* buffer, int len) { ptr_ = buffer; length_ = len; } void set(const char* str) { ptr_ = str; length_ = static_cast<int>(strlen(str)); } void set(const void* buffer, int len) { ptr_ = reinterpret_cast<const char*>(buffer); length_ = len; } char operator[](int i) const { return ptr_[i]; } void remove_prefix(int n) { ptr_ += n; length_ -= n; } void remove_suffix(int n) { length_ -= n; } bool operator==(const StringPiece& x) const { return ((length_ == x.length_) && (memcmp(ptr_, x.ptr_, length_) == 0)); } bool operator!=(const StringPiece& x) const { return !(*this == x); } #define STRINGPIECE_BINARY_PREDICATE(cmp,auxcmp) \ bool operator cmp (const StringPiece& x) const { \ int r = memcmp(ptr_, x.ptr_, length_ < x.length_ ? length_ : x.length_); \ return ((r auxcmp 0) || ((r == 0) && (length_ cmp x.length_))); \ } STRINGPIECE_BINARY_PREDICATE(<, <); STRINGPIECE_BINARY_PREDICATE(<=, <); STRINGPIECE_BINARY_PREDICATE(>=, >); STRINGPIECE_BINARY_PREDICATE(>, >); #undef STRINGPIECE_BINARY_PREDICATE int compare(const StringPiece& x) const { int r = memcmp(ptr_, x.ptr_, length_ < x.length_ ? length_ : x.length_); if (r == 0) { if (length_ < x.length_) r = -1; else if (length_ > x.length_) r = +1; } return r; } string as_string() const { return string(data(), size()); } void CopyToString(string* target) const { target->assign(ptr_, length_); } // Does "this" start with "x" bool starts_with(const StringPiece& x) const { return ((length_ >= x.length_) && (memcmp(ptr_, x.ptr_, x.length_) == 0)); } }; } // namespace pcrecpp // ------------------------------------------------------------------ // Functions used to create STL containers that use StringPiece // Remember that a StringPiece's lifetime had better be less than // that of the underlying string or char*. If it is not, then you // cannot safely store a StringPiece into an STL container // ------------------------------------------------------------------ #ifdef HAVE_TYPE_TRAITS // This makes vector<StringPiece> really fast for some STL implementations template<> struct __type_traits<pcrecpp::StringPiece> { typedef __true_type has_trivial_default_constructor; typedef __true_type has_trivial_copy_constructor; typedef __true_type has_trivial_assignment_operator; typedef __true_type has_trivial_destructor; typedef __true_type is_POD_type; }; #endif // allow StringPiece to be logged PCRECPP_EXP_DECL std::ostream& operator<<(std::ostream& o, const pcrecpp::StringPiece& piece); #endif /* _PCRE_STRINGPIECE_H */