summaryrefslogtreecommitdiffstats
path: root/src/corelib/tools/qvsnprintf.cpp
blob: 0b85cf0c0aa1a05fec1e3aa210f36fbe9ca93cf8 (plain)
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
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
/****************************************************************************
**
** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the QtCore module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** GNU Lesser General Public License Usage
** This file may be used under the terms of the GNU Lesser General Public
** License version 2.1 as published by the Free Software Foundation and
** appearing in the file LICENSE.LGPL included in the packaging of this
** file. Please review the following information to ensure the GNU Lesser
** General Public License version 2.1 requirements will be met:
** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights. These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU General
** Public License version 3.0 as published by the Free Software Foundation
** and appearing in the file LICENSE.GPL included in the packaging of this
** file. Please review the following information to ensure the GNU General
** Public License version 3.0 requirements will be met:
** http://www.gnu.org/copyleft/gpl.html.
**
** Other Usage
** Alternatively, this file may be used in accordance with the terms and
** conditions contained in a signed written agreement between you and Nokia.
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

#include "qplatformdefs.h"

#include "qbytearray.h"
#include "qstring.h"

#include "string.h"

QT_BEGIN_NAMESPACE

#ifndef QT_VSNPRINTF

/*!
    \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::sprintf()
    instead.

    \sa qsnprintf(), QString::sprintf()
*/

int qvsnprintf(char *str, size_t n, const char *fmt, va_list ap)
{
    if (!str || !fmt)
        return -1;

    QString buf;
    buf.vsprintf(fmt, ap);

    QByteArray ba = buf.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

/*!
    \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::sprintf() to format a string instead.

    \sa qvsnprintf(), QString::sprintf()
*/

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