hookcom.cpp

文件加密的过滤驱动程序源代码.

////////////////////////////////////////////////////////////////////////////////////
//
//HookCom.cpp:	common function used both in GUI and Device.

#include "StdAfx.h"
#include "..\HookShr\Comdef.h"

//extract first record containing protected file information from s, 
//save the information in pProtFile and char *path.
//
//return value: return 0 if a record is not found, -1 if a record is not complete,
//						and 1 if a record is read out successfully.
int StringToFileInfo(const char *buf, PROTECTED_FILE *pProtFile, char *path)
{
	//INI file format: each record consist of a '@' followed by length of the path
	//(4 char, including a whitespace),a '#' followed by protection type(3 char,
	//including a whitespace) and anther '#' followed
	//by the path of a file under protection.

	//find first '@':
	unsigned int pos=0;
	while(buf[pos]!='@' && pos<=strlen(buf))
		pos++;
	if(pos>=strlen(buf))
		return -1;

	pos++;
	unsigned int pathLen=atoi(buf+pos);		//read path length.
	pos+=4;
	if(buf[pos]!=',')					//wrong format
		return 0;
	pos++;
	pProtFile->PF_type=atoi(buf+pos);		  //read protection type.
	pos+=3;
	if(buf[pos]!=',')					//wrong format
		return 0;
	pos++;
	strcpy(path, buf+pos);
	if(strlen(path)<pathLen)
		return 0;
	else pProtFile->PF_pPath=path;

	return 1;
}

//Get directory(no file name) form a path by removing last component of a path.
//e.g.  E:\*.* ==> E:\
//		  E:\NEW\A.TXT ==> E:\NEW\
//		  E:\NEW\ ==> E:\NEW\
//Return Value: Length of the new dir.
int GetDir(char *pPath)
{
	int pos=strlen(pPath)-1;
	
	while(pos!=0 && pPath[pos]!='\\' && pPath[pos]!=':')
		pos--;

	if(pPath[pos]==':')
		pPath[++pos]='\\';
	pPath[pos+1]=0;

	return pos+1;
}

//determine whether uniMatcher matches uniPattern. using Long File Name match.
template <class PCHAR_T> BOOL PatternMatch(PCHAR_T pattern, PCHAR_T matcher, unsigned int patternLen, unsigned int matcherLen)
{
	unsigned int pos1=0, pos2=0;
	
	while(pos1<patternLen && pos2<matcherLen)
	{
		if(pattern[pos1]!=matcher[pos2])
		{
			if(pattern[pos1]=='*')
			{
				pos1++;
				while(pos1<patternLen && pos2<matcherLen && pattern[pos1]!=matcher[pos2])
					pos2++;
			}
			else if(pattern[pos1]=='?')
			{
				pos1++;
				pos2++;
			}
			else return FALSE;
		}
		else
		{
			pos1++;
			pos2++;
		}
	}

	if((pos2==matcherLen && pos1==patternLen) || (pattern[patternLen-1]=='*' && (pos1==patternLen-1|| pos1==patternLen)))
		return TRUE;

	return FALSE;
}