WinStd/include/WinStd/Common.h

624 lines
19 KiB
C++

/*
Copyright 1991-2016 Amebis
Copyright 2016 GÉANT
This file is part of WinStd.
Setup is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
Setup is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with Setup. If not, see <http://www.gnu.org/licenses/>.
*/
#pragma once
#include <Windows.h>
#include <assert.h>
#include <stdarg.h>
#include <memory>
#include <string>
#ifndef WINSTD_STACK_BUFFER_BYTES
///
/// Size of the stack buffer in bytes used for initial system function call
///
/// Some system functions with variable length output data fail for
/// insufficient buffer sizes, and return an exact buffer length required.
/// The function helpers use a fixed size stack buffer first. If the stack
/// buffer really prooved sufficient, the helper allocates the exact length
/// output on heap and copies the data without calling the system function
/// again. Otherwise it allocates the exact length output on heap and retries.
///
/// \note
/// Decrease this value in case of stack overflow.
///
#define WINSTD_STACK_BUFFER_BYTES 1024
#endif
// Do not use _vsnprintf_s/_vsnwprintf_s(), since it terminates string by force even when we explicitly want to write unterminated string.
// Threfore turn off compiler warning instead. ;)
#pragma warning(push)
#pragma warning(disable: 4995)
#pragma warning(disable: 4996)
inline int vsnprintf(_Out_z_cap_(capacity) char *str, _In_ size_t capacity, _In_z_ _Printf_format_string_ const char *format, _In_ va_list arg)
{
return _vsnprintf(str, capacity, format, arg);
}
inline int vsnprintf(_Out_z_cap_(capacity) wchar_t *str, _In_ size_t capacity, _In_z_ _Printf_format_string_ const wchar_t *format, _In_ va_list arg)
{
return _vsnwprintf(str, capacity, format, arg);
}
///
/// Formats string using `printf()`.
///
/// \param[out] str Formatted string
/// \param[in ] format String template using `printf()` style
/// \param[in ] arg Arguments to `format`
///
/// \returns Number of characters in result.
///
template<class _Elem, class _Traits, class _Ax>
inline int vsprintf(_Out_ std::basic_string<_Elem, _Traits, _Ax> &str, _In_z_ _Printf_format_string_ const _Elem *format, _In_ va_list arg)
{
_Elem buf[WINSTD_STACK_BUFFER_BYTES/sizeof(_Elem)];
// Try with stack buffer first.
int count = vsnprintf(buf, _countof(buf) - 1, format, arg);
if (count >= 0) {
// Copy from stack.
str.assign(buf, count);
} else {
for (size_t capacity = 2*WINSTD_STACK_BUFFER_BYTES/sizeof(_Elem);; capacity *= 2) {
// Allocate on heap and retry.
auto buf = std::unique_ptr<_Elem[]>(new _Elem[capacity]);
count = vsnprintf(buf.get(), capacity - 1, format, arg);
if (count >= 0) {
str.assign(buf.get(), count);
break;
}
}
}
return count;
}
#pragma warning(pop)
///
/// Formats string using `printf()`.
///
/// \param[out] str Formatted string
/// \param[in ] format String template using `printf()` style
///
/// \returns Number of characters in result.
///
template<class _Elem, class _Traits, class _Ax>
inline int sprintf(_Out_ std::basic_string<_Elem, _Traits, _Ax> &str, _In_z_ _Printf_format_string_ const _Elem *format, ...)
{
va_list arg;
va_start(arg, format);
int res = vsprintf(str, format, arg);
va_end(arg);
return res;
}
namespace winstd
{
#ifdef _UNICODE
typedef std::wstring tstring;
#else
typedef std::string tstring;
#endif
///
/// \defgroup WinStdSysHandles System Handles
/// Simplifies work with object handles of various type
///
/// @{
///
/// Base abstract template class to support generic object handle keeping
///
/// It provides basic operators and methods common to all descendands of this class establishing a base to ease the replacement of native object handle type with classes in object-oriented approach.
///
template <class T> class handle
{
public:
///
/// Datatype of the object handle this template class handles
///
typedef T handle_type;
///
/// Initializes a new class instance with the object handle set to NULL.
///
inline handle() : m_h(NULL)
{
}
///
/// Initializes a new class instance with an available object handle.
///
/// \param[in] h Initial object handle value
///
inline handle(_In_opt_ handle_type h) : m_h(h)
{
}
/// \name Operators for transparent usage of this class
/// @{
///
/// Auto-typecasting operator
///
/// \return Object handle
///
inline operator handle_type() const
{
return m_h;
}
///
/// Returns the object handle value when the object handle is a pointer to a value (class, struct, etc.).
///
/// \return Object handle value
///
inline handle_type*& operator*() const
{
assert(m_h != NULL);
return *m_h;
}
///
/// Returns the object handle reference.
/// \return Object handle reference
///
inline handle_type* operator&()
{
assert(m_h == NULL);
return &m_h;
}
///
/// Provides object handle member access when the object handle is a pointer to a class or struct.
///
/// \return Object handle
///
inline handle_type operator->() const
{
assert(m_h != NULL);
return m_h;
}
/// @}
/// \name Comparison operators
/// @{
///
/// Tests if the object handle is NULL.
///
/// \return
/// - Non zero when object handle is NULL;
/// - Zero otherwise.
///
inline bool operator!() const
{
return m_h == NULL;
}
///
/// Is handle less than?
///
/// \param[in] h Object handle to compare against
/// \return
/// - Non zero when object handle is less than h;
/// - Zero otherwise.
///
inline bool operator<(_In_opt_ handle_type h) const
{
return m_h < h;
}
///
/// Is handle less than or equal to?
///
/// \param[in] h Object handle to compare against
/// \return
/// - Non zero when object handle is less than or equal to h;
/// - Zero otherwise.
///
inline bool operator<=(_In_opt_ handle_type h) const
{
return m_h <= h;
}
///
/// Is handle greater than or equal to?
///
/// \param[in] h Object handle to compare against
/// \return
/// - Non zero when object handle is greater than or equal to h;
/// - Zero otherwise.
///
inline bool operator>=(_In_opt_ handle_type h) const
{
return m_h >= h;
}
///
/// Is handle greater than?
///
/// \param[in] h Object handle to compare against
/// \return
/// - Non zero when object handle is greater than h;
/// - Zero otherwise.
///
inline bool operator>(_In_opt_ handle_type h) const
{
return m_h > h;
}
///
/// Is handle not equal to?
///
/// \param[in] h Object handle to compare against
/// \return
/// - Non zero when object handle is not equal to h;
/// - Zero otherwise.
///
inline bool operator!=(_In_opt_ handle_type h) const
{
return !operator==(h);
}
///
/// Is handle equal to?
///
/// \param[in] h Object handle to compare against
/// \return
/// - Non zero when object handle is equal to h;
/// - Zero otherwise.
///
inline bool operator==(_In_opt_ handle_type h) const
{
return m_h == h;
}
/// @}
///
/// Sets a new object handle for the class
///
/// When the current object handle of the class is non-NULL, the object is destroyed first.
///
/// \param[in] h New object handle
///
inline void attach(_In_opt_ handle_type h)
{
if (m_h)
free_internal();
m_h = h;
}
///
/// Dismisses the object handle from this class
///
/// \return Object handle
///
inline handle_type detach()
{
handle_type h = m_h;
m_h = NULL;
return h;
}
///
/// Destroys the object
///
inline void Free()
{
if (m_h) {
free_internal();
m_h = NULL;
}
}
/// @}
protected:
///
/// Abstract member function that must be implemented by child classes to do the actual object destruction.
///
virtual void free_internal() = 0;
protected:
handle_type m_h; ///< Object handle
};
///
/// Base abstract template class to support object handle keeping for objects that support handle duplication
///
template <class T>
class dplhandle : public handle<T>
{
public:
///
/// Duplicates and returns a new object handle.
///
/// \return Duplicated object handle
///
inline handle_type duplicate() const
{
return m_h ? duplicate_internal(m_h) : NULL;
}
///
/// Duplicates an object handle and sets a new object handle.
///
/// \param[in] h Object handle of existing object
///
/// \return
/// - TRUE when duplication succeeds;
/// - FALSE when duplication fails. In case of failure obtaining the extended error information is object type specific (for example: `GetLastError()`).
///
inline bool attach_duplicated(_In_opt_ handle_type h)
{
if (m_h)
free_internal();
return h ? (m_h = duplicate_internal(h)) != NULL : (m_h = NULL, TRUE);
}
//
// Do not allow = operators. They are semantically ambigious:
// Do they attach the class to the existing instance of object, or do they duplicate it?
// To avoid confusion, user should use attach() and Duplicate() methods explicitly.
//
//inline const dplhandle<T>& operator=(_In_ const handle_type src)
//{
// attach(src ? duplicate_internal(src) : NULL);
// return *this;
//}
//inline const dplhandle<T>& operator=(_In_ const dplhandle<T> &src)
//{
// attach(src.m_h ? duplicate_internal(src.m_h) : NULL);
// return *this;
//}
protected:
///
/// Abstract member function that must be implemented by child classes to do the actual object handle duplication.
///
/// \param[in] h Object handle of existing object
///
/// \return Duplicated object handle
///
virtual handle_type duplicate_internal(_In_ handle_type h) const = 0;
};
/// @}
///
/// \defgroup WinStdStrFormat String Formatting
/// Formatted string generation
///
/// \par Example
/// \code
/// // Please note the PCSTR typecasting invokes an operator to return
/// // pointer to formatted buffer rather than class reference itself.
/// cout << (PCSTR)(string_printf("%i is less than %i.\n", 1, 5));
/// \endcode
///
/// @{
///
/// Base template class to support string formatting using `printf()` style templates
///
template<class _Elem, class _Traits = char_traits<_Elem>, class _Ax = allocator<_Elem> >
class basic_string_printf : public std::basic_string<_Elem, _Traits, _Ax>
{
public:
/// \name Initializing string using template in memory
/// @{
///
/// Initializes a new string and formats its contents using `printf()` style template.
///
/// \param[in] format String template using `printf()` style
///
basic_string_printf(_In_z_ _Printf_format_string_ const _Elem *format, ...)
{
va_list arg;
va_start(arg, format);
vsprintf(*this, format, arg);
va_end(arg);
}
/// @}
/// \name Initializing string using template in resources
/// @{
///
/// Initializes a new string and formats its contents using `printf()` style template in resources.
///
/// \param[in] hInstance Resource module handle
/// \param[in] nFormatID Resource ID of the string template using `printf()` style
///
basic_string_printf(_In_ HINSTANCE hInstance, _In_ UINT nFormatID, ...)
{
_Myt format;
ATLENSURE(format.LoadString(hInstance, nFormatID));
va_list arg;
va_start(arg, nFormatID);
vsprintf(*this, format, arg);
va_end(arg);
}
///
/// Initializes a new string and formats its contents using `printf()` style template in resources.
///
/// \param[in] hInstance Resource module handle
/// \param[in] wLanguageID Resource language
/// \param[in] nFormatID Resource ID of the string template using `printf()` style
///
basic_string_printf(_In_ HINSTANCE hInstance, _In_ WORD wLanguageID, _In_ UINT nFormatID, ...)
{
_Myt format;
ATLENSURE(format.LoadString(hInstance, nFormatID, wLanguageID));
va_list arg;
va_start(arg, nFormatID);
vsprintf(*this, format, arg);
va_end(arg);
}
/// }@
};
///
/// Single-byte character implementation of a class to support string formatting using `printf()` style templates
///
typedef basic_string_printf<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> > string_printf;
///
/// Wide character implementation of a class to support string formatting using `printf()` style templates
///
typedef basic_string_printf<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t>> wstring_printf;
///
/// Base template class to support string formatting using `FormatMessage()` style templates
///
template<class _Elem, class _Traits = char_traits<_Elem>, class _Ax = allocator<_Elem> >
class basic_string_msg : public std::basic_string<_Elem, _Traits, _Ax>
{
public:
/// \name Initializing string using template in memory
/// @{
///
/// Initializes a new string and formats its contents using `FormatMessage()` style template.
///
/// \param[in] format String template using `FormatMessage()` style
///
basic_string_msg(_In_z_ _FormatMessage_format_string_ const _Elem *format, ...)
{
va_list arg;
va_start(arg, format);
FormatMessageV(format, &arg);
va_end(arg);
}
/// @}
/// \name Initializing string using template in resources
/// @{
///
/// Initializes a new string and formats its contents using `FormatMessage()` style template in resources.
///
/// \param[in] hInstance Resource module handle
/// \param[in] nFormatID Resource ID of the string template using `FormatMessage()` style
///
basic_string_msg(_In_ HINSTANCE hInstance, _In_ UINT nFormatID, ...)
{
_Myt format(GetManager());
ATLENSURE(format.LoadString(hInstance, nFormatID));
va_list arg;
va_start(arg, nFormatID);
FormatMessageV(format, &arg);
va_end(arg);
}
///
/// Initializes a new string and formats its contents using `FormatMessage()` style template in resources.
///
/// \param[in] hInstance Resource module handle
/// \param[in] wLanguageID Resource language
/// \param[in] nFormatID Resource ID of the string template using `FormatMessage()` style
///
basic_string_msg(_In_ HINSTANCE hInstance, _In_ WORD wLanguageID, _In_ UINT nFormatID, ...)
{
_Myt format(GetManager());
ATLENSURE(format.LoadString(hInstance, nFormatID, wLanguageID));
va_list arg;
va_start(arg, nFormatID);
FormatMessageV(format, &arg);
va_end(arg);
}
/// @}
};
///
/// Single-byte character implementation of a class to support string formatting using `FormatMessage()` style templates
///
typedef basic_string_msg<char, std::char_traits<char>, std::allocator<char> > string_msg;
///
/// Wide character implementation of a class to support string formatting using `FormatMessage()` style templates
///
typedef basic_string_msg<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> > wstring_msg;
/// @}
/// \defgroup WinStdMemSanitize Auto-sanitize Memory Management
/// Sanitizes memory before dismissed
///
/// @{
///
/// An allocator template that sanitizes each memory block before it is destroyed or reallocated
///
/// \note
/// sanitizing_allocator introduces a performance penalty. However, it provides an additional level of security.
/// Use for security sensitive data memory storage only.
///
template <class _Ty>
class sanitizing_allocator : public std::allocator<_Ty> {
public:
///
/// Sanitizes memory before freeing it
///
/// \param[in] p Pointer to heap memory block
///
void deallocate(_In_ pointer p, _In_ size_type count)
{
// Sanitize then free.
SecureZeroMemory(p, sizeof(_Ty)*count);
std::allocator<_Ty>::deallocate(p, count);
}
};
/// @}
}