hschumann2/TempleOS-Source-Code

1 2I64 FSize(CFile *f)3{//Report size of opened file in bytes.4  if (f)5    return f->de.size;6  else7    return 0;8}9 10CFile *FOpen(U8 *filename,U8 *flags,I64 cnt=0)11{//Allows flags "r","w","w+". "c" for contiguous.12//(It uses StrOcc() for 'w', 'r', '+', 'c')13  CFile *f=CAlloc(sizeof(CFile));14  CDirContext *dirc;15  U8 *full_name;16  Bool contiguous=StrOcc(flags,'c');17 18  f->clus=INVALID_CLUS;19  f->fblk_num=0;20  if (cnt>0)21    f->max_blk=cnt-1;22  else23    f->max_blk=I64_MAX;24  f->file_clus_num=INVALID_CLUS;25  full_name=FileNameAbs(filename);26  f->dv=Let2Drv(*full_name);27  if (f->dv->fs_type==FSt_REDSEA)28    contiguous=TRUE;29  if (contiguous) {30    f->flags|=FF_CONTIGUOUS;31    if (f->dv->fs_type!=FSt_REDSEA &&32          !(FileAttr(filename) & RS_ATTR_CONTIGUOUS))33      throw('File');34  }35  f->clus_buf=CAlloc(f->dv->spc<<BLK_SIZE_BITS);36  if (StrOcc(flags,'w')) {37    f->flags=f->flags|FF_WRITE|FF_NEEDS_WRITE;38    if (StrOcc(flags,'+')) {39      if (FileFind(full_name,&f->de,FUF_JUST_FILES)) {40        Free(full_name);41        if (contiguous)42          f->max_blk=(FSize(f)+BLK_SIZE-1)>>BLK_SIZE_BITS-1;43        return f;44      }45    } else46      Del(full_name,,,FALSE);47    f->de.full_name=full_name;48    f->flags|=FF_NEW_FILE;49    if (dirc=DirContextNew(full_name)) {50      StrCpy(f->de.name,dirc->mask);51      if (cnt>0) {//We pre-alloc the whole thing.52        f->de.clus=ClusAlloc(f->dv,0,53              (cnt+f->dv->spc-1)/f->dv->spc,contiguous);54        f->de.size=cnt<<BLK_SIZE_BITS;55        DirNew(dirc->dv,Fs->cur_dir,&f->de,TRUE);56        f->flags&=~FF_NEW_FILE;57      }58      DirContextDel(dirc);59      return f;60    }61  } else {62    if (FileFind(full_name,&f->de,FUF_JUST_FILES)) {63      Free(full_name);64      f->max_blk=(FSize(f)+BLK_SIZE-1)>>BLK_SIZE_BITS-1;65      return f;66    }67  }68  Free(f->clus_buf);69  Free(full_name);70  Free(f);71  return NULL;72}73 74U0 FClose(CFile *f)75{//Close CFile, updating directory.76  CDirContext *dirc;77  if (f) {78    if (f->flags & FF_BUF_DIRTY) {79      ClusWrite(f->dv,f->clus_buf,f->clus,1);80      f->flags&=~FF_BUF_DIRTY;81    }82    if (f->flags & FF_NEEDS_WRITE) {83      if (dirc=DirContextNew(f->de.full_name)) {84        if (!(f->flags & FF_USE_OLD_DATETIME))85          f->de.datetime=Now;86        if (f->flags & FF_NEW_FILE)87          DirNew(dirc->dv,Fs->cur_dir,&f->de,TRUE);88        else89          DirNew(dirc->dv,Fs->cur_dir,&f->de,FALSE);90        DirContextDel(dirc);91      } else92        throw('File');93    }94    Free(f->clus_buf);95    Free(f->de.full_name);96    Free(f);97  }98}99 100I64 FSetClus(CFile *f,I64 c,I64 blk,Bool read)101{102  CDrv *dv=f->dv;103  I64 i;104  if (f->clus!=c) {105    if (f->flags & FF_BUF_DIRTY) {106      i=dv->spc;107      if (f->max_blk!=I64_MAX) {108        i=f->max_blk+1-f->file_clus_num*dv->spc;109        if (i>dv->spc)110          i=dv->spc;111      }112      ClusBlkWrite(dv,f->clus_buf,f->clus,i);113      f->flags=f->flags & ~FF_BUF_DIRTY;114    }115    f->clus=c;116    f->file_clus_num=blk/dv->spc;117    if (read) {118      i=dv->spc;119      if (f->max_blk!=I64_MAX) {120        i=f->max_blk+1-f->file_clus_num*dv->spc;121        if (i>dv->spc)122          i=dv->spc;123      }124      c=ClusBlkRead(dv,f->clus_buf,c,i);125    }126  }127  return c;128}129 130Bool FBlkRead(CFile *f,U8 *buf,I64 blk=FFB_NEXT_BLK,I64 cnt=1)131{//Read [nth,n+cnt) blks of file.132  CDrv *dv=f->dv;133  I64 spc=dv->spc,i,j,c=f->de.clus;134  if (!f || !dv) return FALSE;135  if (blk==FFB_NEXT_BLK)136    blk=f->fblk_num;137  if (blk+cnt-1>f->max_blk)138    return FALSE;139  if (cnt<=0) return TRUE;140 141  if (f->flags & FF_CONTIGUOUS) {142    BlkRead(dv,buf,Clus2Blk(dv,c)+blk,cnt);143    blk+=cnt;144  } else {145    i=blk/spc;146    if (0<=f->file_clus_num<=i) {147      c=f->clus;148      i-=f->file_clus_num;149    }150    if (i>0)151      c=ClusNumNext(dv,c,i);152 153    if (i=blk%spc) {154      c=FSetClus(f,c,blk,TRUE);155      if (cnt<spc-i)156        j=cnt;157      else158        j=spc-i;159      MemCpy(buf,f->clus_buf+i<<BLK_SIZE_BITS,j<<BLK_SIZE_BITS);160      buf+=j<<BLK_SIZE_BITS;161      cnt-=j;162      blk+=j;163    }164    while (cnt>=spc) {165      c=FSetClus(f,c,blk,TRUE);166      MemCpy(buf,f->clus_buf,spc<<BLK_SIZE_BITS);167      buf+=spc<<BLK_SIZE_BITS;168      cnt-=spc;169      blk+=spc;170    }171    if (cnt>0) {172      c=FSetClus(f,c,blk,TRUE);173      MemCpy(buf,f->clus_buf,cnt<<BLK_SIZE_BITS);174      buf+=cnt<<BLK_SIZE_BITS;175      blk+=cnt;176    }177  }178  f->fblk_num=blk;179  return TRUE;180}181 182Bool FBlkWrite(CFile *f,U8 *buf,I64 blk=FFB_NEXT_BLK,I64 cnt=1)183{//Write [nth,n+cnt) blks of file.184  CDrv *dv=f->dv;185  I64 spc=dv->spc,i,j,c=f->de.clus,c1;186  if (!f || !dv) return FALSE;187  if (blk==FFB_NEXT_BLK)188    blk=f->fblk_num;189  if (blk+cnt-1>f->max_blk)190    return FALSE;191  if (!(f->flags & FF_WRITE))192    return FALSE;193  if (cnt<=0) return TRUE;194  if (f->flags & FF_CONTIGUOUS) {195    BlkWrite(dv,buf,Clus2Blk(dv,c)+blk,cnt);196    blk+=cnt;197  } else {198    if (!c) {199      c=ClusAlloc(dv,0,1,FALSE);200      f->file_clus_num=0;201      f->clus=c;202      f->de.clus=c;203      f->flags|=FF_NEEDS_WRITE|FF_NEW_FILE;204    }205    i=blk/spc;206    if (0<=f->file_clus_num<=i) {207      c=f->clus;208      i-=f->file_clus_num;209    }210    while (i>0) {211      c1=c;212      c=ClusNumNext(dv,c1,1);213      if (c==INVALID_CLUS) {214        c=ClusAlloc(dv,c1,i,FALSE);215        if (i>1)216          c=ClusNumNext(dv,c,i-1);217        break;218      } else219        i--;220    }221 222    if (i=blk%spc) {223      FSetClus(f,c,blk,TRUE);224      if (cnt<spc-i)225        j=cnt;226      else227        j=spc-i;228      MemCpy(f->clus_buf+BLK_SIZE*i,buf,j<<BLK_SIZE_BITS);229      f->flags|=FF_BUF_DIRTY;230      buf+=j<<BLK_SIZE_BITS;231      cnt-=j;232      blk+=j;233      if (cnt>0) {234        c1=c;235        c=ClusNumNext(dv,c1,1);236        if (c==INVALID_CLUS)237          c=ClusAlloc(dv,c1,1,FALSE);238      }239    }240    while (cnt>=spc) {241      FSetClus(f,c,blk,FALSE);242      MemCpy(f->clus_buf,buf,spc<<BLK_SIZE_BITS);243      f->flags|=FF_BUF_DIRTY;244      buf+=spc<<BLK_SIZE_BITS;245      cnt-=spc;246      blk+=spc;247      if (cnt>0) {248        c1=c;249        c=ClusNumNext(dv,c1,1);250        if (c==INVALID_CLUS)251          c=ClusAlloc(dv,c1,1,FALSE);252      }253    }254    if (cnt>0) {255      FSetClus(f,c,blk,TRUE);256      MemCpy(f->clus_buf,buf,cnt<<BLK_SIZE_BITS);257      f->flags|=FF_BUF_DIRTY;258      buf+=cnt<<BLK_SIZE_BITS;259      blk+=cnt;260    }261    if (f->de.size<blk<<BLK_SIZE_BITS)262      f->de.size=blk<<BLK_SIZE_BITS;263  }264  f->fblk_num=blk;265  return TRUE;266}267