1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
|
// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
#include "qplatformdefs.h"
#include "qbytearray.h"
#include "qstring.h"
#include "string.h"
QT_BEGIN_NAMESPACE
#if !defined(QT_VSNPRINTF) || defined(Q_QDOC)
/*!
\relates QByteArray
A portable \c vsnprintf() function. Will call \c ::vsnprintf(), \c
::_vsnprintf(), or \c ::vsnprintf_s depending on the system, or
fall back to an internal version.
\a fmt is the \c printf() format string. The result is put into
\a str, which is a buffer of at least \a n bytes.
The caller is responsible to call \c va_end() on \a ap.
\warning Since vsnprintf() shows different behavior on certain
platforms, you should not rely on the return value or on the fact
that you will always get a 0 terminated string back.
Ideally, you should never call this function but use QString::asprintf()
instead.
\sa qsnprintf(), QString::asprintf()
*/
int qvsnprintf(char *str, size_t n, const char *fmt, va_list ap)
{
if (!str || !fmt)
return -1;
const QByteArray ba = QString::vasprintf(fmt, ap).toLocal8Bit();
if (n > 0) {
size_t blen = qMin(size_t(ba.length()), size_t(n - 1));
memcpy(str, ba.constData(), blen);
str[blen] = '\0'; // make sure str is always 0 terminated
}
return ba.length();
}
#else
QT_BEGIN_INCLUDE_NAMESPACE
#include <stdio.h>
QT_END_INCLUDE_NAMESPACE
int qvsnprintf(char *str, size_t n, const char *fmt, va_list ap)
{
return QT_VSNPRINTF(str, n, fmt, ap);
}
#endif
/*!
\target bytearray-qsnprintf
\relates QByteArray
A portable snprintf() function, calls qvsnprintf.
\a fmt is the \c printf() format string. The result is put into
\a str, which is a buffer of at least \a n bytes.
\warning Call this function only when you know what you are doing
since it shows different behavior on certain platforms.
Use QString::asprintf() to format a string instead.
\sa qvsnprintf(), QString::asprintf()
*/
int qsnprintf(char *str, size_t n, const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
int ret = qvsnprintf(str, n, fmt, ap);
va_end(ap);
return ret;
}
QT_END_NAMESPACE
|