code/trunk/pcre_stringpiece.h.in

// 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 <string.h>
#include <string>
#include <iosfwd>    // for ostream forward-declaration

#if @pcre_has_type_traits@
#define HAVE_TYPE_TRAITS
#include <type_traits.h>
#elif @pcre_has_bits_type_traits@
#define HAVE_TYPE_TRAITS
#include <bits/type_traits.h>
#endif

using std::string;

namespace pcrecpp {

class 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(str))) { }
  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
std::ostream& operator<<(std::ostream& o, const pcrecpp::StringPiece& piece);

#endif /* _PCRE_STRINGPIECE_H */
1	// Copyright (c) 2005, Google Inc.
2	// All rights reserved.
3	//
4	// Redistribution and use in source and binary forms, with or without
5	// modification, are permitted provided that the following conditions are
6	// met:
7	//
8	// * Redistributions of source code must retain the above copyright
9	// notice, this list of conditions and the following disclaimer.
10	// * Redistributions in binary form must reproduce the above
11	// copyright notice, this list of conditions and the following disclaimer
12	// in the documentation and/or other materials provided with the
13	// distribution.
14	// * Neither the name of Google Inc. nor the names of its
15	// contributors may be used to endorse or promote products derived from
16	// this software without specific prior written permission.
17	//
18	// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19	// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20	// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21	// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22	// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23	// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24	// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25	// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26	// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27	// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28	// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29	//
30	// Author: Sanjay Ghemawat
31	//
32	// A string like object that points into another piece of memory.
33	// Useful for providing an interface that allows clients to easily
34	// pass in either a "const char*" or a "string".
35	//
36	// Arghh! I wish C++ literals were automatically of type "string".
37
38	#ifndef _PCRE_STRINGPIECE_H
39	#define _PCRE_STRINGPIECE_H
40
41	#include <string.h>
42	#include <string>
43	#include <iosfwd> // for ostream forward-declaration
44
45	#if @pcre_has_type_traits@
46	#define HAVE_TYPE_TRAITS
47	#include <type_traits.h>
48	#elif @pcre_has_bits_type_traits@
49	#define HAVE_TYPE_TRAITS
50	#include <bits/type_traits.h>
51	#endif
52
53	using std::string;
54
55	namespace pcrecpp {
56
57	class StringPiece {
58	private:
59	const char* ptr_;
60	int length_;
61
62	public:
63	// We provide non-explicit singleton constructors so users can pass
64	// in a "const char*" or a "string" wherever a "StringPiece" is
65	// expected.
66	StringPiece()
67	: ptr_(NULL), length_(0) { }
68	StringPiece(const char* str)
69	: ptr_(str), length_(static_cast<int>(strlen(str))) { }
70	StringPiece(const string& str)
71	: ptr_(str.data()), length_(static_cast<int>(str.size())) { }
72	StringPiece(const char* offset, int len)
73	: ptr_(offset), length_(len) { }
74
75	// data() may return a pointer to a buffer with embedded NULs, and the
76	// returned buffer may or may not be null terminated. Therefore it is
77	// typically a mistake to pass data() to a routine that expects a NUL
78	// terminated string. Use "as_string().c_str()" if you really need to do
79	// this. Or better yet, change your routine so it does not rely on NUL
80	// termination.
81	const char* data() const { return ptr_; }
82	int size() const { return length_; }
83	bool empty() const { return length_ == 0; }
84
85	void clear() { ptr_ = NULL; length_ = 0; }
86	void set(const char* buffer, int len) { ptr_ = buffer; length_ = len; }
87	void set(const char* str) {
88	ptr_ = str;
89	length_ = static_cast<int>(strlen(str));
90	}
91	void set(const void* buffer, int len) {
92	ptr_ = reinterpret_cast<const char*>(buffer);
93	length_ = len;
94	}
95
96	char operator[](int i) const { return ptr_[i]; }
97
98	void remove_prefix(int n) {
99	ptr_ += n;
100	length_ -= n;
101	}
102
103	void remove_suffix(int n) {
104	length_ -= n;
105	}
106
107	bool operator==(const StringPiece& x) const {
108	return ((length_ == x.length_) &&
109	(memcmp(ptr_, x.ptr_, length_) == 0));
110	}
111	bool operator!=(const StringPiece& x) const {
112	return !(*this == x);
113	}
114
115	#define STRINGPIECE_BINARY_PREDICATE(cmp,auxcmp) \
116	bool operator cmp (const StringPiece& x) const { \
117	int r = memcmp(ptr_, x.ptr_, length_ < x.length_ ? length_ : x.length_); \
118	return ((r auxcmp 0) \|\| ((r == 0) && (length_ cmp x.length_))); \
119	}
120	STRINGPIECE_BINARY_PREDICATE(<, <);
121	STRINGPIECE_BINARY_PREDICATE(<=, <);
122	STRINGPIECE_BINARY_PREDICATE(>=, >);
123	STRINGPIECE_BINARY_PREDICATE(>, >);
124	#undef STRINGPIECE_BINARY_PREDICATE
125
126	int compare(const StringPiece& x) const {
127	int r = memcmp(ptr_, x.ptr_, length_ < x.length_ ? length_ : x.length_);
128	if (r == 0) {
129	if (length_ < x.length_) r = -1;
130	else if (length_ > x.length_) r = +1;
131	}
132	return r;
133	}
134
135	string as_string() const {
136	return string(data(), size());
137	}
138
139	void CopyToString(string* target) const {
140	target->assign(ptr_, length_);
141	}
142
143	// Does "this" start with "x"
144	bool starts_with(const StringPiece& x) const {
145	return ((length_ >= x.length_) && (memcmp(ptr_, x.ptr_, x.length_) == 0));
146	}
147	};
148
149	} // namespace pcrecpp
150
151	// ------------------------------------------------------------------
152	// Functions used to create STL containers that use StringPiece
153	// Remember that a StringPiece's lifetime had better be less than
154	// that of the underlying string or char*. If it is not, then you
155	// cannot safely store a StringPiece into an STL container
156	// ------------------------------------------------------------------
157
158	#ifdef HAVE_TYPE_TRAITS
159	// This makes vector<StringPiece> really fast for some STL implementations
160	template<> struct __type_traits<pcrecpp::StringPiece> {
161	typedef __true_type has_trivial_default_constructor;
162	typedef __true_type has_trivial_copy_constructor;
163	typedef __true_type has_trivial_assignment_operator;
164	typedef __true_type has_trivial_destructor;
165	typedef __true_type is_POD_type;
166	};
167	#endif
168
169	// allow StringPiece to be logged
170	std::ostream& operator<<(std::ostream& o, const pcrecpp::StringPiece& piece);
171
172	#endif /* _PCRE_STRINGPIECE_H */