1 内存管理

1.1 内存管理基础

标准内存管理函数

windows内存管理api

各类内存函数操作的对象

GlobalMemoryStatus 获取系统的内存使用状态

1 固定的内存块

GlobalAlloc 申请 需要指定flag GMEM_FIXED

2 可移动的内存块

操作系统会进行碎片整理

3 可丢弃的内存块

GMEM_MOVEABLE GMEM_DISCARDABLE

堆管理函数

操作私有堆 不同的线程可以在不同的私有堆中操作内存

GetProcessHeaps 列出进程中所有的堆

虚拟内存管理

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其它内存管理函数

RtlMoveMemory

复制内存

填充内存

内存置0

2 文件操作

文件句柄和读写指针

• 文件函数的操作对象包括 文件、串口、磁盘设备、网络文件、控制 台和目录等
• 支持异步文件操作
• 文件的共享和锁定
• 内存映射文件
• 拷贝文件和移动文件
  文件名长度<=255
  不合法的文件名字符

/\:*?"<>|

NTFS 文件系统 支持对文件进行访问控制

HANDLE CreateFile(    LPCTSTR lpFileName, // pointer to name of the file     DWORD dwDesiredAccess,  // access (read-write) mode GENERIC_READ | GENERIC_WRITE    DWORD dwShareMode,  // share mode     LPSECURITY_ATTRIBUTES lpSecurityAttributes, // pointer to security attributes     DWORD dwCreationDistribution,   // how to create     DWORD dwFlagsAndAttributes, // file attributes     HANDLE hTemplateFile    // handle to file with attributes to copy     );

CloseHandle

BOOL CloseHandle(    HANDLE hObject  // handle to object to close     );

设置文件指针

DWORD SetFilePointer(    HANDLE hFile,   // handle of file     LONG lDistanceToMove,   // number of bytes to move file pointer     PLONG lpDistanceToMoveHigh, // address of high-order word of distance to move      DWORD dwMoveMethod  // how to move    );   返回移动后的文件指针invoke SetFilePointer,hFile,0,NULL,FILE_CURRENT可获取当前的文件指针

SetEndOfFile 用来截断文件

文件的读写

BOOL ReadFile(    HANDLE hFile,   // handle of file to read     LPVOID lpBuffer,    // address of buffer that receives data      DWORD nNumberOfBytesToRead, // number of bytes to read 要读取的字节数    LPDWORD lpNumberOfBytesRead,    // address of number of bytes read 实际读取到的字节数    LPOVERLAPPED lpOverlapped   // address of structure for data    );BOOL WriteFile(    HANDLE hFile,   // handle to file to write to     LPCVOID lpBuffer,   // pointer to data to write to file     DWORD nNumberOfBytesToWrite,    // number of bytes to write     LPDWORD lpNumberOfBytesWritten, // pointer to number of bytes written     LPOVERLAPPED lpOverlapped   // pointer to structure needed for overlapped I/O   );    将缓冲区中的数据立即写入文件BOOL FlushFileBuffers(    HANDLE hFile    // open handle to file whose buffers are to be flushed    );

文件的共享

对文件的某一部分加锁BOOL LockFile(    HANDLE hFile,   // handle of file to lock     DWORD dwFileOffsetLow,  // low-order word of lock region offset     DWORD dwFileOffsetHigh, // high-order word of lock region offset      DWORD nNumberOfBytesToLockLow,  // low-order word of length to lock     DWORD nNumberOfBytesToLockHigh  // high-order word of length to lock    );解锁BOOL UnlockFile(    HANDLE hFile,   // handle of file to unlock     DWORD dwFileOffsetLow,  // low-order word of lock region offset     DWORD dwFileOffsetHigh, // high-order word of lock region offset      DWORD nNumberOfBytesToUnlockLow,    // low-order word of length to unlock     DWORD nNumberOfBytesToUnlockHigh    // high-order word of length to unlock    );

查找文件

HANDLE FindFirstFile(    LPCTSTR lpFileName, // pointer to name of file to search for      LPWIN32_FIND_DATA lpFindFileData    // pointer to returned information    );BOOL FindNextFile(    HANDLE hFindFile,   // handle to search      LPWIN32_FIND_DATA lpFindFileData    // pointer to structure for data on found file     );    BOOL FindClose(    HANDLE hFindFile    // file search handle    );typedef struct _WIN32_FIND_DATA { // wfd      DWORD dwFileAttributes;     FILETIME ftCreationTime;     FILETIME ftLastAccessTime;     FILETIME ftLastWriteTime;     DWORD    nFileSizeHigh;     DWORD    nFileSizeLow;     DWORD    dwReserved0;     DWORD    dwReserved1;     TCHAR    cFileName[ MAX_PATH ]; //文件名，不包括路径名    TCHAR    cAlternateFileName[ 14 ]; //8.3结构的短文件名} WIN32_FIND_DATA;

image.png

字符串函数

lstrcpylstrcat

文件的属性

获取文件类型DWORD GetFileType(    HANDLE hFile    // file handle    );   4种类型FILE_TYPE_UNKNOWN   The type of the specified file is unknown.FILE_TYPE_DISK  The specified file is a disk file.FILE_TYPE_CHAR  The specified file is a character file, typically an LPT device or a console.FILE_TYPE_PIPE  The specified file is either a named or anonymous pipe. 获取文件长度DWORD GetFileSize(    HANDLE hFile,   // handle of file to get size of    LPDWORD lpFileSizeHigh  // address of high-order word for file size   );返回长度的低32位获取文件时间BOOL GetFileTime(    HANDLE hFile,   // identifies the file     LPFILETIME lpCreationTime,  // address of creation time 创建时间    LPFILETIME lpLastAccessTime,    // address of last access time  最后访问时间    LPFILETIME lpLastWriteTime  // address of last write time 最后写入时间   );typedef struct _FILETIME { // ft      DWORD dwLowDateTime;     DWORD dwHighDateTime; } FILETIME; 将FILETIME拷入LARGE_INTEGER共用体 typedef union _LARGE_INTEGER {      struct {        DWORD LowPart;          LONG  HighPart;     };    LONGLONG QuadPart;} LARGE_INTEGER; //将文件时间转化为系统时间BOOL FileTimeToSystemTime(    CONST FILETIME *lpFileTime, // pointer to file time to convert     LPSYSTEMTIME lpSystemTime   // pointer to structure to receive system time     );//设置文件时间BOOL SetFileTime(    HANDLE hFile,   // identifies the file     CONST FILETIME *lpCreationTime, // time the file was created     CONST FILETIME *lpLastAccessTime,   // time the file was last accessed     CONST FILETIME *lpLastWriteTime     // time the file was last written    );BOOL SystemTimeToFileTime(    CONST SYSTEMTIME *lpSystemTime, // address of system time to convert     LPFILETIME lpFileTime   // address of buffer for converted file time    );DWORD GetFileAttributes(    LPCTSTR lpFileName  // address of the name of a file or directory     );BOOL SetFileAttributes(    LPCTSTR lpFileName, // address of filename     DWORD dwFileAttributes  // address of attributes to set    );拷贝文件BOOL CopyFile(    LPCTSTR lpExistingFileName, // pointer to name of an existing file     LPCTSTR lpNewFileName,  // pointer to filename to copy to     BOOL bFailIfExists  // flag for operation if file exists    );移动文件BOOL MoveFile(    LPCTSTR lpExistingFileName, // address of name of the existing file      LPCTSTR lpNewFileName   // address of new name for the file    );   MoveFileEx 删除文件BOOL DeleteFile(    LPCTSTR lpFileName  // pointer to name of file to delete     );

3 驱动器和目录

逻辑分区

逻辑驱动器操作

修改和删除卷标 c d e f 的名称BOOL SetVolumeLabel(    LPCTSTR lpRootPathName, // address of name of root directory for volume     LPCTSTR lpVolumeName    // name for the volume    );检查逻辑驱动器是否存在 返回的32位整数，表示 A-Z是否存在DWORD GetLogicalDrives(VOID)返回存在的逻辑驱动器的字符串 如"C:\",0,"D:\",0DWORD GetLogicalDriveStrings(    DWORD nBufferLength,    // size of buffer     LPTSTR lpBuffer     // address of buffer for drive strings    );获取驱动器类型UINT GetDriveType(    LPCTSTR lpRootPathName  // address of root path    );返回值0   The drive type cannot be determined.1   The root directory does not exist.DRIVE_REMOVABLE The drive can be removed from the drive.DRIVE_FIXED The disk cannot be removed from the drive.DRIVE_REMOTE    The drive is a remote (network) drive.DRIVE_CDROM The drive is a CD-ROM drive.DRIVE_RAMDISK   The drive is a RAM disk.获取卷的详细信息BOOL GetVolumeInformation(    LPCTSTR lpRootPathName, // address of root directory of the file system     LPTSTR lpVolumeNameBuffer,  // address of name of the volume     DWORD nVolumeNameSize,  // length of lpVolumeNameBuffer     LPDWORD lpVolumeSerialNumber,   // address of volume serial number     LPDWORD lpMaximumComponentLength,   // address of system's maximum filename length    LPDWORD lpFileSystemFlags,  // address of file system flags     LPTSTR lpFileSystemNameBuffer,  // address of name of file system     DWORD nFileSystemNameSize   // length of lpFileSystemNameBuffer    );获取驱动器空闲空间BOOL GetDiskFreeSpace(    LPCTSTR lpRootPathName, // address of root path     LPDWORD lpSectorsPerCluster,    // address of sectors per cluster 每簇的扇区数    LPDWORD lpBytesPerSector,   // address of bytes per sector 每个扇区的字节数    LPDWORD lpNumberOfFreeClusters, // address of number of free clusters  空闲的簇 数    LPDWORD lpTotalNumberOfClusters     // address of total number of clusters  簇的总数   );

目录操作

创建目录BOOL CreateDirectory(    LPCTSTR lpPathName, // pointer to a directory path string    LPSECURITY_ATTRIBUTES lpSecurityAttributes  // pointer to a security descriptor    );删除目录BOOL RemoveDirectory(    LPCTSTR lpPathName  // address of directory to remove     );

windows系统中的特殊目录

• 当前目录
• windows目录 windows系统的安装目录
• 系统目录 windows系统中安装目录下存放系统文件的目录 system32
• 临时目录 存放临时文件的目录

DWORD GetCurrentDirectory(    DWORD nBufferLength,    // size, in characters, of directory buffer     LPTSTR lpBuffer     // address of buffer for current directory    );    DWORD GetTempPath(    DWORD nBufferLength,    // size, in characters, of the buffer     LPTSTR lpBuffer     // address of buffer for temp. path    );UINT GetWindowsDirectory(    LPTSTR lpBuffer,    // address of buffer for Windows directory     UINT uSize  // size of directory buffer    );UINT GetSystemDirectory(    LPTSTR lpBuffer,    // address of buffer for system directory     UINT uSize  // size of directory buffer    );BOOL SetCurrentDirectory(    LPCTSTR lpPathName  // address of name of new current directory    );

4 内存映射文件

是win32中最有实用价值的新特征之一，使得程序访问文件如同访问内存一样，可用于不同的程序共享内存

用内存映射文件加载执行文件

用内存映射文件实现进程间通信

使用内存映射

使用内存映射

step 1创建内存映射HANDLE CreateFileMapping(    HANDLE hFile,   // handle to file to map 若用于进程间通信这个参数为-1    LPSECURITY_ATTRIBUTES lpFileMappingAttributes,  // optional security attributes 用来表示句柄是否被继承    DWORD flProtect,    // protection for mapping object  保护类型    DWORD dwMaximumSizeHigh,    // high-order 32 bits of object size      DWORD dwMaximumSizeLow, // low-order 32 bits of object size  指定大小 进程间通信为0    LPCTSTR lpName  // name of file-mapping object 用于进程间通信的话必须设置   );打开映射文件HANDLE OpenFileMapping(    DWORD dwDesiredAccess,  // access mode FILE_MAP_READ FILE_MAP_WRITE FILE_MAP_COPY    BOOL bInheritHandle,    // inherit flag     LPCTSTR lpName  // pointer to name of file-mapping object    );step 2 映射文件LPVOID MapViewOfFile(    HANDLE hFileMappingObject,  // file-mapping object to map into address space      DWORD dwDesiredAccess,  // access mode     DWORD dwFileOffsetHigh, // high-order 32 bits of file offset     DWORD dwFileOffsetLow,  // low-order 32 bits of file offset 映射的起始位置    DWORD dwNumberOfBytesToMap  // number of bytes to map  映射的数据大小为 0的话，映射整个文件   );会返回一个地址，用该地址就可以存取文件使用结束后取消映射BOOL UnmapViewOfFile(    LPCVOID lpBaseAddress   // address where mapped view begins     );使用CloseHandle关闭内存映射句柄将内存映射的内容立即写入磁盘BOOL FlushViewOfFile(    LPCVOID lpBaseAddress,  // start address of byte range to flush      DWORD dwNumberOfBytesToFlush    // number of bytes in range    );