Qt 4.8
qvsnprintf.cpp
Go to the documentation of this file.
1 /****************************************************************************
2 **
3 ** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
4 ** Contact: http://www.qt-project.org/legal
5 **
6 ** This file is part of the QtCore module of the Qt Toolkit.
7 **
8 ** $QT_BEGIN_LICENSE:LGPL$
9 ** Commercial License Usage
10 ** Licensees holding valid commercial Qt licenses may use this file in
11 ** accordance with the commercial license agreement provided with the
12 ** Software or, alternatively, in accordance with the terms contained in
13 ** a written agreement between you and Digia. For licensing terms and
14 ** conditions see http://qt.digia.com/licensing. For further information
15 ** use the contact form at http://qt.digia.com/contact-us.
16 **
17 ** GNU Lesser General Public License Usage
18 ** Alternatively, this file may be used under the terms of the GNU Lesser
19 ** General Public License version 2.1 as published by the Free Software
20 ** Foundation and appearing in the file LICENSE.LGPL included in the
21 ** packaging of this file. Please review the following information to
22 ** ensure the GNU Lesser General Public License version 2.1 requirements
23 ** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
24 **
25 ** In addition, as a special exception, Digia gives you certain additional
26 ** rights. These rights are described in the Digia Qt LGPL Exception
27 ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
28 **
29 ** GNU General Public License Usage
30 ** Alternatively, this file may be used under the terms of the GNU
31 ** General Public License version 3.0 as published by the Free Software
32 ** Foundation and appearing in the file LICENSE.GPL included in the
33 ** packaging of this file. Please review the following information to
34 ** ensure the GNU General Public License version 3.0 requirements will be
35 ** met: http://www.gnu.org/copyleft/gpl.html.
36 **
37 **
38 ** $QT_END_LICENSE$
39 **
40 ****************************************************************************/
41 
42 #include "qplatformdefs.h"
43 
44 #include "qbytearray.h"
45 #include "qstring.h"
46 
47 #include "string.h"
48 
50 
51 #ifndef QT_VSNPRINTF
52 
78 int qvsnprintf(char *str, size_t n, const char *fmt, va_list ap)
79 {
80  if (!str || !fmt)
81  return -1;
82 
83  QString buf;
84  buf.vsprintf(fmt, ap);
85 
86  QByteArray ba = buf.toLocal8Bit();
87 
88  if (n > 0) {
89  size_t blen = qMin(size_t(ba.length()), size_t(n - 1));
90  memcpy(str, ba.constData(), blen);
91  str[blen] = '\0'; // make sure str is always 0 terminated
92  }
93 
94  return ba.length();
95 }
96 
97 #else
98 
100 #include <stdio.h>
102 
103 int qvsnprintf(char *str, size_t n, const char *fmt, va_list ap)
104 {
105  return QT_VSNPRINTF(str, n, fmt, ap);
106 }
107 
108 #endif
109 
128 int qsnprintf(char *str, size_t n, const char *fmt, ...)
129 {
130  va_list ap;
131  va_start(ap, fmt);
132 
133  int ret = qvsnprintf(str, n, fmt, ap);
134  va_end(ap);
135 
136  return ret;
137 }
138 
Q_DECL_CONSTEXPR const T & qMin(const T &a, const T &b)
Definition: qglobal.h:1215
#define QT_END_NAMESPACE
This macro expands to.
Definition: qglobal.h:90
The QByteArray class provides an array of bytes.
Definition: qbytearray.h:135
#define QT_END_INCLUDE_NAMESPACE
This macro is equivalent to QT_BEGIN_NAMESPACE.
Definition: qglobal.h:92
The QString class provides a Unicode character string.
Definition: qstring.h:83
QString & vsprintf(const char *format, va_list ap)
Equivalent method to sprintf(), but takes a va_list ap instead a list of variable arguments...
Definition: qstring.cpp:5587
#define QT_BEGIN_NAMESPACE
This macro expands to.
Definition: qglobal.h:89
int qvsnprintf(char *str, size_t n, const char *fmt, va_list ap)
A portable vsnprintf() function.
Definition: qvsnprintf.cpp:78
QByteArray toLocal8Bit() const Q_REQUIRED_RESULT
Returns the local 8-bit representation of the string as a QByteArray.
Definition: qstring.cpp:4049
int length() const
Same as size().
Definition: qbytearray.h:356
const char * constData() const
Returns a pointer to the data stored in the byte array.
Definition: qbytearray.h:433
int qsnprintf(char *str, size_t n, const char *fmt,...)
A portable snprintf() function, calls qvsnprintf.
Definition: qvsnprintf.cpp:128
#define QT_BEGIN_INCLUDE_NAMESPACE
This macro is equivalent to QT_END_NAMESPACE.
Definition: qglobal.h:91