1 // Copyright (C) 2009-2013, International Business Machines
2 // Corporation and others. All Rights Reserved.
3 //
4 // Copyright 2004 and onwards Google Inc.
5 //
6 // Author: wilsonh@google.com (Wilson Hsieh)
7 //
8
9 #include "unicode/utypes.h"
10 #include "unicode/stringpiece.h"
11 #include "cstring.h"
12 #include "cmemory.h"
13
14 U_NAMESPACE_BEGIN
15
StringPiece(const char * str)16 StringPiece::StringPiece(const char* str)
17 : ptr_(str), length_((str == NULL) ? 0 : static_cast<int32_t>(uprv_strlen(str))) { }
18
StringPiece(const StringPiece & x,int32_t pos)19 StringPiece::StringPiece(const StringPiece& x, int32_t pos) {
20 if (pos < 0) {
21 pos = 0;
22 } else if (pos > x.length_) {
23 pos = x.length_;
24 }
25 ptr_ = x.ptr_ + pos;
26 length_ = x.length_ - pos;
27 }
28
StringPiece(const StringPiece & x,int32_t pos,int32_t len)29 StringPiece::StringPiece(const StringPiece& x, int32_t pos, int32_t len) {
30 if (pos < 0) {
31 pos = 0;
32 } else if (pos > x.length_) {
33 pos = x.length_;
34 }
35 if (len < 0) {
36 len = 0;
37 } else if (len > x.length_ - pos) {
38 len = x.length_ - pos;
39 }
40 ptr_ = x.ptr_ + pos;
41 length_ = len;
42 }
43
set(const char * str)44 void StringPiece::set(const char* str) {
45 ptr_ = str;
46 if (str != NULL)
47 length_ = static_cast<int32_t>(uprv_strlen(str));
48 else
49 length_ = 0;
50 }
51
52 U_EXPORT UBool U_EXPORT2
operator ==(const StringPiece & x,const StringPiece & y)53 operator==(const StringPiece& x, const StringPiece& y) {
54 int32_t len = x.size();
55 if (len != y.size()) {
56 return false;
57 }
58 if (len == 0) {
59 return true;
60 }
61 const char* p = x.data();
62 const char* p2 = y.data();
63 // Test last byte in case strings share large common prefix
64 --len;
65 if (p[len] != p2[len]) return false;
66 // At this point we can, but don't have to, ignore the last byte.
67 return uprv_memcmp(p, p2, len) == 0;
68 }
69
70
71 /* Microsoft Visual Studio (even 2013) complains about redefinition of this
72 * static const class variable. However, the C++ standard states that this
73 * definition is correct. Perhaps there is a bug in the Microsoft compiler.
74 * This is not an issue on any other compilers (that we know of).
75 * Cygwin with MSVC 9.0 also complains here about redefinition.
76 */
77 #if (!defined(_MSC_VER) || (_MSC_VER > 1800)) && !defined(CYGWINMSVC)
78 const int32_t StringPiece::npos = 0x7fffffff;
79 #endif
80
81 U_NAMESPACE_END
82