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39
40#ifndef QDATABUFFER_P_H
41#define QDATABUFFER_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 other Qt classes. This header file may change from version to
49// version without notice, or even be removed.
50//
51// We mean it.
52//
53
54#include <QtGui/private/qtguiglobal_p.h>
55#include "QtCore/qbytearray.h"
56
57#include <stdlib.h>
58
59QT_BEGIN_NAMESPACE
60
61template <typename Type> class QDataBuffer
62{
63 Q_DISABLE_COPY_MOVE(QDataBuffer)
64public:
65 QDataBuffer(int res)
66 {
67 capacity = res;
68 if (res) {
69 QT_WARNING_PUSH
70 QT_WARNING_DISABLE_GCC("-Walloc-size-larger-than=")
71 buffer = (Type*) malloc(size: capacity * sizeof(Type));
72 QT_WARNING_POP
73 Q_CHECK_PTR(buffer);
74 } else {
75 buffer = nullptr;
76 }
77 siz = 0;
78 }
79
80 ~QDataBuffer()
81 {
82 if (buffer)
83 free(buffer);
84 }
85
86 inline void reset() { siz = 0; }
87
88 inline bool isEmpty() const { return siz==0; }
89
90 inline int size() const { return siz; }
91 inline Type *data() const { return buffer; }
92
93 inline Type &at(int i) { Q_ASSERT(i >= 0 && i < siz); return buffer[i]; }
94 inline const Type &at(int i) const { Q_ASSERT(i >= 0 && i < siz); return buffer[i]; }
95 inline Type &last() { Q_ASSERT(!isEmpty()); return buffer[siz-1]; }
96 inline const Type &last() const { Q_ASSERT(!isEmpty()); return buffer[siz-1]; }
97 inline Type &first() { Q_ASSERT(!isEmpty()); return buffer[0]; }
98 inline const Type &first() const { Q_ASSERT(!isEmpty()); return buffer[0]; }
99
100 inline void add(const Type &t) {
101 reserve(size: siz + 1);
102 buffer[siz] = t;
103 ++siz;
104 }
105
106 inline void pop_back() {
107 Q_ASSERT(siz > 0);
108 --siz;
109 }
110
111 inline void resize(int size) {
112 reserve(size);
113 siz = size;
114 }
115
116 inline void reserve(int size) {
117 if (size > capacity) {
118 if (capacity == 0)
119 capacity = 1;
120 while (capacity < size)
121 capacity *= 2;
122 buffer = (Type*) realloc(buffer, capacity * sizeof(Type));
123 Q_CHECK_PTR(buffer);
124 }
125 }
126
127 inline void shrink(int size) {
128 capacity = size;
129 if (size) {
130 buffer = (Type*) realloc(buffer, capacity * sizeof(Type));
131 Q_CHECK_PTR(buffer);
132 } else {
133 free(buffer);
134 buffer = nullptr;
135 }
136 }
137
138 inline void swap(QDataBuffer<Type> &other) {
139 qSwap(capacity, other.capacity);
140 qSwap(siz, other.siz);
141 qSwap(buffer, other.buffer);
142 }
143
144 inline QDataBuffer &operator<<(const Type &t) { add(t); return *this; }
145
146private:
147 int capacity;
148 int siz;
149 Type *buffer;
150};
151
152QT_END_NAMESPACE
153
154#endif // QDATABUFFER_P_H
155

source code of qtbase/src/gui/painting/qdatabuffer_p.h