void create_fs ( ){
/*进入此函数证明当前硬盘无任何操作系统，需要初始化superBlock，扇区位图，文件分配表*/
/*superBlock*/
memcpy8("TINY",superBlock.sign,5);/*文件系统标识*/
superBlock.n_sects=hd_info.sectorNum;
superBlock.n_inode=MAX_FILE;
/*扇区位图，注：前32个扇区存储文件系统的信息，一定处于使用状态*/
int i;
for(i=0;i<DATA_START;i++)
mask1(i);
for(i=DATA_START;i<superBlock.n_sects;i++)
mask0(i);
/*文件分配表,初始时全部无效化*/
fat.size=0;
for(i=0;i<MAX_FILE;i++)
fat.i_node_arr[i].status=I_NODE_INVALID;
/*将信息全部写入硬盘*/
u_int8 buf[512];
/*写superBlock*/
memcpy8((u_int8*)&superBlock,buf,SUPERBLOCK_SIZE);
while(write_sector(SUPERBLOCK_START,buf)==FALSE);
/*写位图*/
u_int32 bmp_sect=((superBlock.n_sects%4096)==0)?(superBlock.n_sects/4096):(superBlock.n_sects/4096+1);
u_int32 pos=0;
for(i=HD_BMP_START;i<HD_BMP_START+bmp_sect;i++,pos+=512)
while(write_sector(i,hd_bmp+pos)==FALSE);
/*写文件分配表*/
pos=0;
for(i=FAT_START;i<FAT_START+MAX_FAT;i++,pos+=512)
while(write_sector(i,((u_int8*)&fat+pos))==FALSE);
}
bool dgDynamicBody::IsInEquilibrium () const
{
if (m_equilibrium) {
dgVector forceError (m_accel - m_prevExternalForce);
dgVector torqueError (m_alpha - m_prevExternalTorque);
dgVector mask0 ((forceError.DotProduct4(forceError) < m_equilibriumError2) & (torqueError.DotProduct4(torqueError) < m_equilibriumError2));
if (mask0.GetSignMask()) {
dgVector invMassMag2 (m_invMass[3] * m_invMass[3]);
dgVector mask1 ((invMassMag2.CompProduct4 (m_netForce.DotProduct4(m_netForce)) < m_equilibriumError2) & (invMassMag2.CompProduct4 (m_netTorque.DotProduct4(m_netTorque)) < m_equilibriumError2));
if (mask1.GetSignMask()) {
dgVector mask2 ((m_veloc.DotProduct4(m_veloc) < m_equilibriumError2) & (m_omega.DotProduct4(m_omega) < m_equilibriumError2));
return mask2.GetSignMask() ? true : false;
}
}
}
return false;
}
u_int32 delete_file ( u_int32 handle ,u_int32 send_pid ){
/*patch：判断权限*/
/*清除文件分配表表项*/
int i;
u_int32 start=fat.i_node_arr[handle].startSector;
u_int32 n_sects=fat.i_node_arr[handle].sectorNum;
fat.i_node_arr[handle].byte_size=0;
fat.i_node_arr[handle].startSector=0;
fat.i_node_arr[handle].sectorNum=0;
fat.i_node_arr[handle].status=I_NODE_INVALID;
fat.size--;
for(i=0;i<MAX_FILE_NAME;i++)
fat.i_node_arr[handle].file_name[i]='\0';
for(i=start;i<start+n_sects;i++)
mask0(i);
return TRUE;
}