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39
40 #include "qwinregistry_p.h"
41
42 #include <QtCore/qvarlengtharray.h>
43
44 #include <algorithm>
45
46 QT_BEGIN_NAMESPACE
47
QWinRegistryKey()48 QWinRegistryKey::QWinRegistryKey() :
49 m_key(nullptr)
50 {
51 }
52
53 // Open a key with the specified permissions (KEY_READ/KEY_WRITE).
54 // "access" is to explicitly use the 32- or 64-bit branch.
QWinRegistryKey(HKEY parentHandle,QStringView subKey,REGSAM permissions,REGSAM access)55 QWinRegistryKey::QWinRegistryKey(HKEY parentHandle, QStringView subKey,
56 REGSAM permissions, REGSAM access)
57 {
58 if (RegOpenKeyEx(parentHandle, reinterpret_cast<const wchar_t *>(subKey.utf16()),
59 0, permissions | access, &m_key) != ERROR_SUCCESS) {
60 m_key = nullptr;
61 }
62 }
63
~QWinRegistryKey()64 QWinRegistryKey::~QWinRegistryKey()
65 {
66 close();
67 }
68
close()69 void QWinRegistryKey::close()
70 {
71 if (isValid()) {
72 RegCloseKey(m_key);
73 m_key = nullptr;
74 }
75 }
76
stringValue(QStringView subKey) const77 QString QWinRegistryKey::stringValue(QStringView subKey) const
78 {
79 QString result;
80 if (!isValid())
81 return result;
82 DWORD type;
83 DWORD size;
84 auto subKeyC = reinterpret_cast<const wchar_t *>(subKey.utf16());
85 if (RegQueryValueEx(m_key, subKeyC, nullptr, &type, nullptr, &size) != ERROR_SUCCESS
86 || (type != REG_SZ && type != REG_EXPAND_SZ) || size <= 2) {
87 return result;
88 }
89 // Reserve more for rare cases where trailing '\0' are missing in registry.
90 // Rely on 0-termination since strings of size 256 padded with 0 have been
91 // observed (QTBUG-84455).
92 size += 2;
93 QVarLengthArray<unsigned char> buffer(static_cast<int>(size));
94 std::fill(buffer.data(), buffer.data() + size, 0u);
95 if (RegQueryValueEx(m_key, subKeyC, nullptr, &type, buffer.data(), &size) == ERROR_SUCCESS)
96 result = QString::fromWCharArray(reinterpret_cast<const wchar_t *>(buffer.constData()));
97 return result;
98 }
99
dwordValue(QStringView subKey) const100 QPair<DWORD, bool> QWinRegistryKey::dwordValue(QStringView subKey) const
101 {
102 if (!isValid())
103 return qMakePair(0, false);
104 DWORD type;
105 auto subKeyC = reinterpret_cast<const wchar_t *>(subKey.utf16());
106 if (RegQueryValueEx(m_key, subKeyC, nullptr, &type, nullptr, nullptr) != ERROR_SUCCESS
107 || type != REG_DWORD) {
108 return qMakePair(0, false);
109 }
110 DWORD value = 0;
111 DWORD size = sizeof(value);
112 const bool ok =
113 RegQueryValueEx(m_key, subKeyC, nullptr, nullptr,
114 reinterpret_cast<unsigned char *>(&value), &size) == ERROR_SUCCESS;
115 return qMakePair(value, ok);
116 }
117
118 QT_END_NAMESPACE
119