C++ AnyString::c_str方法代码示例

	File::File(const AnyString& filePath):
		pFormat(nullptr)
	{
		if (filePath.empty())
			return;

		# if LIBAVFORMAT_VERSION_MAJOR < 53
		if (::av_open_input_file(&pFormat, filePath.c_str(), nullptr, 0, nullptr))
		# else
		if (::avformat_open_input(&pFormat, filePath.c_str(), nullptr, nullptr))
		# endif // LIBAVFORMAT_VERSION_MAJOR < 53
		{
			pFormat = nullptr;
			return;
		}

		// After opening, we must search for the stream information because not
		// all formats will have it in stream headers (eg. system MPEG streams)
		# if LIBAVFORMAT_VERSION_MAJOR < 53
		if (::av_find_stream_info(pFormat) < 0)
		# else
		if (::avformat_find_stream_info(pFormat, nullptr) < 0)
		# endif // LIBAVFORMAT_VERSION_MAJOR < 53
		{
			# if LIBAVFORMAT_VERSION_MAJOR < 53
			::av_close_input_file(pFormat);
			# else
			::avformat_close_input(&pFormat);
			# endif // LIBAVFORMAT_VERSION_MAJOR < 53
			pFormat = nullptr;
			return;
		}
	}

	Yuni::IO::NodeType TypeOf(const AnyString& filename)
	{
		if (filename.empty())
			return Yuni::IO::typeUnknown;

		# ifdef YUNI_OS_WINDOWS
		const char* p = filename.c_str();
		unsigned int len = filename.size();
		if (p[len - 1] == '\\' or p[len - 1] == '/')
		{
			if (!--len)
			{
				# ifdef YUNI_OS_WINDOWS
				return Yuni::IO::typeUnknown;
				# else
				// On Unixes, `/` is a valid folder
				return Yuni::IO::typeFolder;
				# endif
			}
		}

		// Driver letters
		if (len == 2 and p[1] == ':')
			return Yuni::IO::typeFolder;

		String  norm;
		Yuni::IO::Normalize(norm, AnyString(p, len));
		// Conversion into wchar_t
		Private::WString<true> wstr(norm);
		if (wstr.empty())
			return Yuni::IO::typeUnknown;

		WIN32_FILE_ATTRIBUTE_DATA infoFile;
		if (!GetFileAttributesExW(wstr.c_str(), GetFileExInfoStandard, &infoFile))
			return Yuni::IO::typeUnknown;

		return ((infoFile.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) != 0)
			? Yuni::IO::typeFolder
			: Yuni::IO::typeFile;

		# else // WINDOWS

		struct stat s;
		if (stat(filename.c_str(), &s) != 0)
			return Yuni::IO::typeUnknown;

		return (S_ISDIR(s.st_mode))
			? Yuni::IO::typeFolder
			: Yuni::IO::typeFile;
		# endif
	}

DBI::Error Transaction::truncate(const AnyString& tablename)
{
    if (YUNI_UNLIKELY(not IsValidIdentifier(tablename)))
        return errInvalidIdentifier;

    assert(!(!pChannel));

    // the adapter
    ::yn_dbi_adapter& adapter = pChannel->adapter;

    // The DBI interface should provide the most appropriate way for
    // truncating a table (autoincrement / cascade...)
    if (YUNI_LIKELY(adapter.truncate))
    {
        return (DBI::Error) adapter.truncate(adapter.dbh, tablename.c_str(), tablename.size());
    }
    else
    {
        // Fallback to a failsafe method
        // -- stmt << "TRUNCATE " << tablename << ';';
        // The SQL command Truncate is not supported by all databases. `DELETE FROM`
        // is not  the most efficient way for truncating a table
        // but it should work almost everywhere
        String stmt;
        stmt << "DELETE FROM " << tablename << ';';
        return perform(stmt);
    }
}

Cursor Transaction::prepare(const AnyString& stmt)
{
    assert(!(!pChannel));

    // the adapter
    ::yn_dbi_adapter& adapter = pChannel->adapter;

    if (YUNI_UNLIKELY(nullHandle == pTxHandle))
    {
        if (errNone != pChannel->begin(pTxHandle))
            return Cursor(adapter, nullptr);
    }

    // query handle
    void* handle = nullptr;

    if (YUNI_LIKELY(not stmt.empty() and adapter.dbh))
    {
        assert(adapter.query_new != NULL  and "invalid adapter query_new");
        assert(adapter.query_ref_acquire != NULL and "invalid adapter query_ref_acquire");
        assert(adapter.query_ref_release != NULL and "invalid adapter query_ref_release");

        adapter.query_new(&handle, adapter.dbh, stmt.c_str(), stmt.size());
    }

    return Cursor(adapter, handle);
}

	bool Size(const AnyString& filename, uint64& value)
	{
		struct stat results;
		if (not filename.empty() && stat(filename.c_str(), &results) == 0)
		{
			value = (uint64) results.st_size;
			return true;
		}
		value = 0u;
		return false;
	}

	Yuni::IO::Error Delete(const AnyString& filename)
	{
		// DeleteFile is actually a macro and will be replaced by DeleteFileW
		// with Visual Studio. Consequently we can not use the word DeleteFile.....

		if (filename.empty())
			return Yuni::IO::errUnknown;

		# ifndef YUNI_OS_WINDOWS

		return (unlink(filename.c_str()))
			? Yuni::IO::errUnknown
			: Yuni::IO::errNone;

		# else

		const char* const p = filename.c_str();
		uint len = filename.size();

		if (p[len - 1] == '\\' or p[len - 1] == '/')
			--len;

		// Driver letters
		if (len == 2 and p[1] == ':')
			return Yuni::IO::errBadFilename;

		String norm;
		Yuni::IO::Normalize(norm, AnyString(p, len));

		// Conversion into wchar_t
		WString wstr(norm, true);
		if (wstr.empty())
			return Yuni::IO::errUnknown;
		wstr.replace('/', '\\');

		return (DeleteFileW(wstr.c_str()))
			? Yuni::IO::errNone
			: Yuni::IO::errUnknown;
		# endif
	}

DBI::Error Transaction::perform(const AnyString& script)
{
    assert(!(!pChannel));

    // the adapter
    ::yn_dbi_adapter& adapter = pChannel->adapter;
    assert(adapter.query_exec != NULL);

    if (YUNI_LIKELY(nullHandle != pTxHandle))
    {
        return (DBI::Error) adapter.query_exec(adapter.dbh, script.c_str(), script.size());
    }
    else
    {
        // start a new transaction
        DBI::Error error = pChannel->begin(pTxHandle);

        if (YUNI_LIKELY(error == errNone))
            error = (DBI::Error) adapter.query_exec(adapter.dbh, script.c_str(), script.size());

        return error;
    }
}

	sint64 LastModificationTime(const AnyString& filename)
	{
		# ifdef YUNI_OS_WINDOWS

		Private::WString<> wfilenm(filename);
		if (wfilenm.empty())
			return 0;
		HANDLE hFile = CreateFileW(wfilenm.c_str(), GENERIC_READ, FILE_SHARE_READ, NULL,
			OPEN_EXISTING, 0, NULL);
		if (hFile == INVALID_HANDLE_VALUE)
			return 0;

		FILETIME ftCreate, ftAccess, ftWrite;
		// Retrieve the file times for the file.
		if (GetFileTime(hFile, &ftCreate, &ftAccess, &ftWrite))
		{
			CloseHandle(hFile);

			LARGE_INTEGER date, adjust;
			date.HighPart = ftWrite.dwHighDateTime;
			date.LowPart = ftWrite.dwLowDateTime;

			// 100-nanoseconds = milliseconds * 10000
			adjust.QuadPart = 11644473600000 * 10000;

			// removes the diff between 1970 and 1601
			date.QuadPart -= adjust.QuadPart;

			// converts back from 100-nanoseconds to seconds
			return date.QuadPart / 10000000;
		}

		CloseHandle(hFile);
		return 0;

		# else // UNIX

		struct stat st;
		if (!stat(filename.c_str(), &st))
			return st.st_mtime;
		return 0;

		# endif
	}

	bool Stream::open(const AnyString& filename, int mode)
	{
		// Close the file if already opened
		if (pFd)
			(void)::fclose(pFd);

		# ifdef YUNI_OS_WINDOWS
		pFd = OpenFileOnWindows(filename, mode);
		# else
		// It is mandatory to open file with the flag O_CLOEXEC to avoid race
		// conditions with fork
		// fopen should used O_CLOEXEC as one of the option. However, at the current
		// state, not all operating systems do that.
		// So we have to do it by ourselves with open and fdopen.
		/*int flag = O_CLOEXEC;
		if (0 != (mode & OpenMode::read) and 0 != (mode & OpenMode::write))
			flag |= O_RDWR;
		else if (0 != (mode & OpenMode::read))
			flag |= O_RDONLY;
		else if (0 != (mode & OpenMode::write))
			flag |= O_WRONLY;

		if (0 != (mode & OpenMode::truncate))
			flag |= O_TRUNC;
		else if (0 != (mode & OpenMode::append))
			flag |= O_APPEND;

		if (0 != (mode & ~OpenMode::read))
			flag |= O_CREAT;

		int fd = ::open(filename.c_str(), flag);
		if (fd < 0) // error
			pFd = nullptr;
		else
			pFd = ::fdopen(fd, OpenMode::ToCString(mode));*/
		pFd = ::fopen(filename.c_str(), OpenMode::ToCString(mode));
		# endif

		return (NULL != pFd);
	}

	static bool UnixMake(const AnyString& path, uint mode)
	{
		const uint len = path.size();
		char* buffer = new char[len + 1];
		YUNI_MEMCPY(buffer, len, path.c_str(), len);
		buffer[len] = '\0';
		char* pt = buffer;
		char tmp;

		do
		{
			if ('\\' == *pt or '/' == *pt or '\0' == *pt)
			{
				tmp = *pt;
				*pt = '\0';
				if ('\0' != buffer[0] and '\0' != buffer[1] and '\0' != buffer[2])
				{
					if (mkdir(buffer, static_cast<mode_t>(mode)) < 0)
					{
						if (errno != EEXIST and errno != EISDIR and errno != ENOSYS)
						{
							delete[] buffer;
							return false;
						}
					}
				}
				if ('\0' == tmp)
					break;
				*pt = tmp;
			}
			++pt;
		}
		while (true);

		delete[] buffer;
		return true;
	}

	void WString::prepareWString(const AnyString& string, bool uncprefix)
	{
		if (string.empty())
		{
			if (uncprefix)
			{
				pSize = 4;
				pWString = (wchar_t*)::realloc(pWString, sizeof(wchar_t) * 5);
				pWString[0] = L'\\';
				pWString[1] = L'\\';
				pWString[2] = L'?';
				pWString[3] = L'\\';
				pWString[4] = L'\0';
			}
			else
				clear();
			return;
		}

		if (string.size() > INT_MAX)
		{
			clear();
			return;
		}

		// Offset according to the presence of the UNC prefix
		const uint offset = (not uncprefix) ? 0 : 4;

		#ifdef YUNI_OS_WINDOWS
		{
			// Allocate and convert the C-String. Several iterations may be required
			// for allocating enough room for the conversion.
			const int sizeRequired = MultiByteToWideChar(CP_UTF8, 0, string.c_str(), string.size(), nullptr, 0);
			if (sizeRequired <= 0)
			{
				clear();
				return;
			}

			pSize = sizeRequired + offset;

			pWString = (wchar_t*) realloc(pWString, sizeof(wchar_t) * (pSize + 1));
			if (nullptr == pWString) // Impossible to allocate the buffer. Aborting.
			{
				clear();
				return;
			}

			// Converting into Wide String
			const int n = MultiByteToWideChar(CP_UTF8, 0, string.c_str(), static_cast<int>(string.size()), pWString + offset, static_cast<int>(pSize - offset));
			if (n != sizeRequired)
			{
				assert(false and "most likely an error");
				clear();
				return;
			}
		}
		#else
		{
			const char* wcstr = string.c_str();

			mbstate_t state;
			memset (&state, '\0', sizeof (state));

			size_t sizeRequired = mbsnrtowcs(nullptr, &wcstr, string.size(), 0, &state);
			if (0 == sizeRequired or (size_t) -1 == sizeRequired)
			{
				clear();
				return;
			}

			pSize = sizeRequired + offset;

			pWString = (wchar_t*) realloc(pWString, sizeof(wchar_t) * (pSize + 1));
			if (nullptr == pWString) // Impossible to allocate the buffer. Aborting.
			{
				clear();
				return;
			}

			memset (&state, '\0', sizeof (state));
			size_t written = mbsnrtowcs(pWString + offset, &wcstr, string.size(), pSize - offset, &state);
			if (0 == written or (size_t) -1 == written)
			{
				clear();
				return;
			}
		}
		#endif


		// prepend the Windows UNC prefix
		if (uncprefix)
		{
			pWString[0] = L'\\';
			pWString[1] = L'\\';
			pWString[2] = L'?';
			pWString[3] = L'\\';
		}

//.........这里部分代码省略.........

	bool Resize(const AnyString& filename, uint64_t size)
	{
		if (not filename.empty())
		{
			if (size < std::numeric_limits<off_t>::max())
			{
				#ifndef YUNI_OS_WINDOWS
				{
					assert((filename.c_str())[filename.size()] == '\0');
					#ifdef YUNI_OS_MAC
					int fd = open(filename.c_str(), O_WRONLY|O_CREAT, 0644);
					#else
					int fd = open(filename.c_str(), O_WRONLY|O_CREAT|O_LARGEFILE, 0644);
					#endif
					if (fd != -1)
					{
						bool success = (0 == ftruncate(fd, static_cast<off_t>(size)));
						close(fd);
						return success;
					}
				}
				#else
				{
					WString wstr(filename, true);
					if (not wstr.empty())
					{
						HANDLE hndl = CreateFileW(wstr.c_str(), GENERIC_WRITE, FILE_SHARE_WRITE, NULL, OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
						if (hndl)
						{
							LARGE_INTEGER li;
							li.QuadPart = size;
							DWORD dwPtr = SetFilePointer(hndl, li.LowPart, &li.HighPart, FILE_BEGIN);
							if (dwPtr != INVALID_SET_FILE_POINTER)
								SetEndOfFile(hndl);
							CloseHandle(hndl);
							return true;
						}
					}
				}
				#endif
			}
		}
		return false;
	}