1 //===------------------------ stdexcept.cpp -------------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is dual licensed under the MIT and the University of Illinois Open
6 // Source Licenses. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "stdexcept"
11 #include "new"
12 #include "string"
13 #include <cstdlib>
14 #include <cstring>
15 #include <cstdint>
16 #include <cstddef>
17 #include "system_error"
18 
19 // Note:  optimize for size
20 
21 #pragma GCC visibility push(hidden)
22 
23 namespace
24 {
25 
26 class __libcpp_nmstr
27 {
28 private:
29     const char* str_;
30 
31     typedef std::size_t unused_t;
32     typedef std::int32_t count_t;
33 
34     static const std::ptrdiff_t offset = static_cast<std::ptrdiff_t>(2*sizeof(unused_t) +
35                                                                        sizeof(count_t));
36 
37     count_t& count() const _NOEXCEPT {return (count_t&)(*(str_ - sizeof(count_t)));}
38 public:
39     explicit __libcpp_nmstr(const char* msg);
40     __libcpp_nmstr(const __libcpp_nmstr& s) _LIBCPP_CANTTHROW;
41     __libcpp_nmstr& operator=(const __libcpp_nmstr& s) _LIBCPP_CANTTHROW;
42     ~__libcpp_nmstr() _LIBCPP_CANTTHROW;
43     const char* c_str() const _NOEXCEPT {return str_;}
44 };
45 
46 __libcpp_nmstr::__libcpp_nmstr(const char* msg)
47 {
48     std::size_t len = strlen(msg);
49     str_ = new char[len + 1 + offset];
50     unused_t* c = (unused_t*)str_;
51     c[0] = c[1] = len;
52     str_ += offset;
53     count() = 0;
54     std::strcpy(const_cast<char*>(c_str()), msg);
55 }
56 
57 inline
58 __libcpp_nmstr::__libcpp_nmstr(const __libcpp_nmstr& s)
59     : str_(s.str_)
60 {
61     __sync_add_and_fetch(&count(), 1);
62 }
63 
64 __libcpp_nmstr&
65 __libcpp_nmstr::operator=(const __libcpp_nmstr& s)
66 {
67     const char* p = str_;
68     str_ = s.str_;
69     __sync_add_and_fetch(&count(), 1);
70     if (__sync_add_and_fetch((count_t*)(p-sizeof(count_t)), -1) < 0)
71         delete [] (p-offset);
72     return *this;
73 }
74 
75 inline
76 __libcpp_nmstr::~__libcpp_nmstr()
77 {
78     if (__sync_add_and_fetch(&count(), -1) < 0)
79         delete [] (str_ - offset);
80 }
81 
82 }
83 
84 #pragma GCC visibility pop
85 
86 namespace std  // purposefully not using versioning namespace
87 {
88 
89 logic_error::logic_error(const string& msg)
90 {
91     __libcpp_nmstr& s = (__libcpp_nmstr&)__imp_;
92     ::new(&s) __libcpp_nmstr(msg.c_str());
93 }
94 
95 logic_error::logic_error(const char* msg)
96 {
97     __libcpp_nmstr& s = (__libcpp_nmstr&)__imp_;
98     ::new(&s) __libcpp_nmstr(msg);
99 }
100 
101 logic_error::logic_error(const logic_error& le) _NOEXCEPT
102 {
103     __libcpp_nmstr& s = (__libcpp_nmstr&)__imp_;
104     ::new(&s) __libcpp_nmstr((const __libcpp_nmstr&)le.__imp_);
105 }
106 
107 logic_error&
108 logic_error::operator=(const logic_error& le) _NOEXCEPT
109 {
110     __libcpp_nmstr& s1 = (__libcpp_nmstr&)__imp_;
111     const __libcpp_nmstr& s2 = (const __libcpp_nmstr&)le.__imp_;
112     s1 = s2;
113     return *this;
114 }
115 
116 logic_error::~logic_error() _NOEXCEPT
117 {
118     __libcpp_nmstr& s = (__libcpp_nmstr&)__imp_;
119     s.~__libcpp_nmstr();
120 }
121 
122 const char*
123 logic_error::what() const _NOEXCEPT
124 {
125     __libcpp_nmstr& s = (__libcpp_nmstr&)__imp_;
126     return s.c_str();
127 }
128 
129 runtime_error::runtime_error(const string& msg)
130 {
131     __libcpp_nmstr& s = (__libcpp_nmstr&)__imp_;
132     ::new(&s) __libcpp_nmstr(msg.c_str());
133 }
134 
135 runtime_error::runtime_error(const char* msg)
136 {
137     __libcpp_nmstr& s = (__libcpp_nmstr&)__imp_;
138     ::new(&s) __libcpp_nmstr(msg);
139 }
140 
141 runtime_error::runtime_error(const runtime_error& le) _NOEXCEPT
142 {
143     __libcpp_nmstr& s = (__libcpp_nmstr&)__imp_;
144     ::new(&s) __libcpp_nmstr((const __libcpp_nmstr&)le.__imp_);
145 }
146 
147 runtime_error&
148 runtime_error::operator=(const runtime_error& le) _NOEXCEPT
149 {
150     __libcpp_nmstr& s1 = (__libcpp_nmstr&)__imp_;
151     const __libcpp_nmstr& s2 = (const __libcpp_nmstr&)le.__imp_;
152     s1 = s2;
153     return *this;
154 }
155 
156 runtime_error::~runtime_error() _NOEXCEPT
157 {
158     __libcpp_nmstr& s = (__libcpp_nmstr&)__imp_;
159     s.~__libcpp_nmstr();
160 }
161 
162 const char*
163 runtime_error::what() const _NOEXCEPT
164 {
165     __libcpp_nmstr& s = (__libcpp_nmstr&)__imp_;
166     return s.c_str();
167 }
168 
169 domain_error::~domain_error() _NOEXCEPT {}
170 invalid_argument::~invalid_argument() _NOEXCEPT {}
171 length_error::~length_error() _NOEXCEPT {}
172 out_of_range::~out_of_range() _NOEXCEPT {}
173 
174 range_error::~range_error() _NOEXCEPT {}
175 overflow_error::~overflow_error() _NOEXCEPT {}
176 underflow_error::~underflow_error() _NOEXCEPT {}
177 
178 }  // std
179