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39 | |
40 | #ifndef QRINGBUFFER_P_H |
41 | #define QRINGBUFFER_P_H |
42 | |
43 | // |
44 | // W A R N I N G |
45 | // ------------- |
46 | // |
47 | // This file is not part of the Qt API. It exists for the convenience |
48 | // of a number of Qt sources files. This header file may change from |
49 | // version to version without notice, or even be removed. |
50 | // |
51 | // We mean it. |
52 | // |
53 | |
54 | #include <QtCore/private/qglobal_p.h> |
55 | #include <QtCore/qbytearray.h> |
56 | #include <QtCore/qvector.h> |
57 | |
58 | QT_BEGIN_NAMESPACE |
59 | |
60 | #ifndef QRINGBUFFER_CHUNKSIZE |
61 | #define QRINGBUFFER_CHUNKSIZE 4096 |
62 | #endif |
63 | |
64 | class QRingChunk |
65 | { |
66 | public: |
67 | // initialization and cleanup |
68 | inline QRingChunk() noexcept : |
69 | headOffset(0), tailOffset(0) |
70 | { |
71 | } |
72 | inline QRingChunk(const QRingChunk &other) noexcept : |
73 | chunk(other.chunk), headOffset(other.headOffset), tailOffset(other.tailOffset) |
74 | { |
75 | } |
76 | explicit inline QRingChunk(int alloc) : |
77 | chunk(alloc, Qt::Uninitialized), headOffset(0), tailOffset(0) |
78 | { |
79 | } |
80 | explicit inline QRingChunk(const QByteArray &qba) noexcept : |
81 | chunk(qba), headOffset(0), tailOffset(qba.size()) |
82 | { |
83 | } |
84 | |
85 | inline QRingChunk &operator=(const QRingChunk &other) noexcept |
86 | { |
87 | chunk = other.chunk; |
88 | headOffset = other.headOffset; |
89 | tailOffset = other.tailOffset; |
90 | return *this; |
91 | } |
92 | inline QRingChunk(QRingChunk &&other) noexcept : |
93 | chunk(other.chunk), headOffset(other.headOffset), tailOffset(other.tailOffset) |
94 | { |
95 | other.headOffset = other.tailOffset = 0; |
96 | } |
97 | inline QRingChunk &operator=(QRingChunk &&other) noexcept |
98 | { |
99 | swap(other); |
100 | return *this; |
101 | } |
102 | |
103 | inline void swap(QRingChunk &other) noexcept |
104 | { |
105 | chunk.swap(other&: other.chunk); |
106 | qSwap(value1&: headOffset, value2&: other.headOffset); |
107 | qSwap(value1&: tailOffset, value2&: other.tailOffset); |
108 | } |
109 | |
110 | // allocating and sharing |
111 | void allocate(int alloc); |
112 | inline bool isShared() const |
113 | { |
114 | return !chunk.isDetached(); |
115 | } |
116 | Q_CORE_EXPORT void detach(); |
117 | QByteArray toByteArray(); |
118 | |
119 | // getters |
120 | inline int head() const |
121 | { |
122 | return headOffset; |
123 | } |
124 | inline int size() const |
125 | { |
126 | return tailOffset - headOffset; |
127 | } |
128 | inline int capacity() const |
129 | { |
130 | return chunk.size(); |
131 | } |
132 | inline int available() const |
133 | { |
134 | return chunk.size() - tailOffset; |
135 | } |
136 | inline const char *data() const |
137 | { |
138 | return chunk.constData() + headOffset; |
139 | } |
140 | inline char *data() |
141 | { |
142 | if (isShared()) |
143 | detach(); |
144 | return chunk.data() + headOffset; |
145 | } |
146 | |
147 | // array management |
148 | inline void advance(int offset) |
149 | { |
150 | Q_ASSERT(headOffset + offset >= 0); |
151 | Q_ASSERT(size() - offset > 0); |
152 | |
153 | headOffset += offset; |
154 | } |
155 | inline void grow(int offset) |
156 | { |
157 | Q_ASSERT(size() + offset > 0); |
158 | Q_ASSERT(head() + size() + offset <= capacity()); |
159 | |
160 | tailOffset += offset; |
161 | } |
162 | inline void assign(const QByteArray &qba) |
163 | { |
164 | chunk = qba; |
165 | headOffset = 0; |
166 | tailOffset = qba.size(); |
167 | } |
168 | inline void reset() |
169 | { |
170 | headOffset = tailOffset = 0; |
171 | } |
172 | inline void clear() |
173 | { |
174 | assign(qba: QByteArray()); |
175 | } |
176 | |
177 | private: |
178 | QByteArray chunk; |
179 | int headOffset, tailOffset; |
180 | }; |
181 | |
182 | class QRingBuffer |
183 | { |
184 | public: |
185 | explicit inline QRingBuffer(int growth = QRINGBUFFER_CHUNKSIZE) : |
186 | bufferSize(0), basicBlockSize(growth) { } |
187 | |
188 | inline void setChunkSize(int size) { |
189 | basicBlockSize = size; |
190 | } |
191 | |
192 | inline int chunkSize() const { |
193 | return basicBlockSize; |
194 | } |
195 | |
196 | inline qint64 nextDataBlockSize() const { |
197 | return bufferSize == 0 ? Q_INT64_C(0) : buffers.first().size(); |
198 | } |
199 | |
200 | inline const char *readPointer() const { |
201 | return bufferSize == 0 ? nullptr : buffers.first().data(); |
202 | } |
203 | |
204 | Q_CORE_EXPORT const char *readPointerAtPosition(qint64 pos, qint64 &length) const; |
205 | Q_CORE_EXPORT void free(qint64 bytes); |
206 | Q_CORE_EXPORT char *reserve(qint64 bytes); |
207 | Q_CORE_EXPORT char *reserveFront(qint64 bytes); |
208 | |
209 | inline void truncate(qint64 pos) { |
210 | Q_ASSERT(pos >= 0 && pos <= size()); |
211 | |
212 | chop(bytes: size() - pos); |
213 | } |
214 | |
215 | Q_CORE_EXPORT void chop(qint64 bytes); |
216 | |
217 | inline bool isEmpty() const { |
218 | return bufferSize == 0; |
219 | } |
220 | |
221 | inline int getChar() { |
222 | if (isEmpty()) |
223 | return -1; |
224 | char c = *readPointer(); |
225 | free(bytes: 1); |
226 | return int(uchar(c)); |
227 | } |
228 | |
229 | inline void putChar(char c) { |
230 | char *ptr = reserve(bytes: 1); |
231 | *ptr = c; |
232 | } |
233 | |
234 | void ungetChar(char c) |
235 | { |
236 | char *ptr = reserveFront(bytes: 1); |
237 | *ptr = c; |
238 | } |
239 | |
240 | |
241 | inline qint64 size() const { |
242 | return bufferSize; |
243 | } |
244 | |
245 | Q_CORE_EXPORT void clear(); |
246 | inline qint64 indexOf(char c) const { return indexOf(c, maxLength: size()); } |
247 | Q_CORE_EXPORT qint64 indexOf(char c, qint64 maxLength, qint64 pos = 0) const; |
248 | Q_CORE_EXPORT qint64 read(char *data, qint64 maxLength); |
249 | Q_CORE_EXPORT QByteArray read(); |
250 | Q_CORE_EXPORT qint64 peek(char *data, qint64 maxLength, qint64 pos = 0) const; |
251 | Q_CORE_EXPORT void append(const char *data, qint64 size); |
252 | Q_CORE_EXPORT void append(const QByteArray &qba); |
253 | |
254 | inline qint64 skip(qint64 length) { |
255 | qint64 bytesToSkip = qMin(a: length, b: bufferSize); |
256 | |
257 | free(bytes: bytesToSkip); |
258 | return bytesToSkip; |
259 | } |
260 | |
261 | Q_CORE_EXPORT qint64 readLine(char *data, qint64 maxLength); |
262 | |
263 | inline bool canReadLine() const { |
264 | return indexOf(c: '\n') >= 0; |
265 | } |
266 | |
267 | private: |
268 | QVector<QRingChunk> buffers; |
269 | qint64 bufferSize; |
270 | int basicBlockSize; |
271 | }; |
272 | |
273 | Q_DECLARE_SHARED(QRingChunk) |
274 | Q_DECLARE_TYPEINFO(QRingBuffer, Q_MOVABLE_TYPE); |
275 | |
276 | QT_END_NAMESPACE |
277 | |
278 | #endif // QRINGBUFFER_P_H |
279 | |