path: root/src/thirdparty/unrar/scantree.cpp

#include "rar.hpp"

ScanTree::ScanTree(StringList *FileMasks,RECURSE_MODE Recurse,bool GetLinks,SCAN_DIRS GetDirs)
{
  ScanTree::FileMasks=FileMasks;
  ScanTree::Recurse=Recurse;
  ScanTree::GetLinks=GetLinks;
  ScanTree::GetDirs=GetDirs;

  ScanEntireDisk=false;

  SetAllMaskDepth=0;
  *CurMask=0;
  memset(FindStack,0,sizeof(FindStack));
  Depth=0;
  Errors=0;
  *ErrArcName=0;
  Cmd=NULL;
}


ScanTree::~ScanTree()
{
  for (int I=Depth;I>=0;I--)
    if (FindStack[I]!=NULL)
      delete FindStack[I];
}


SCAN_CODE ScanTree::GetNext(FindData *FindData)
{
  if (Depth<0)
    return SCAN_DONE;


  SCAN_CODE FindCode;
  while (1)
  {
    if (*CurMask==0 && !GetNextMask())
      return SCAN_DONE;


    FindCode=FindProc(FindData);
    if (FindCode==SCAN_ERROR)
    {
      Errors++;
      continue;
    }
    if (FindCode==SCAN_NEXT)
      continue;
    if (FindCode==SCAN_SUCCESS && FindData->IsDir && GetDirs==SCAN_SKIPDIRS)
      continue;
    if (FindCode==SCAN_DONE && GetNextMask())
      continue;
    break;
  }
  return(FindCode);
}


bool ScanTree::GetNextMask()
{
  if (!FileMasks->GetString(CurMask,ASIZE(CurMask)))
    return false;
  CurMask[ASIZE(CurMask)-1]=0;
#ifdef _WIN_ALL
  UnixSlashToDos(CurMask,CurMask,ASIZE(CurMask));
#endif

  // We wish to scan entire disk if mask like c:\ is specified
  // regardless of recursion mode. Use c:\*.* mask when need to scan only 
  // the root directory.
  ScanEntireDisk=IsDiskLetter(CurMask) && IsPathDiv(CurMask[2]) && CurMask[3]==0;

  wchar *Name=PointToName(CurMask);
  if (*Name==0)
    wcsncatz(CurMask,MASKALL,ASIZE(CurMask));
  if (Name[0]=='.' && (Name[1]==0 || Name[1]=='.' && Name[2]==0))
  {
    AddEndSlash(CurMask,ASIZE(CurMask));
    wcsncatz(CurMask,MASKALL,ASIZE(CurMask));
  }
  SpecPathLength=Name-CurMask;
  Depth=0;

  wcscpy(OrigCurMask,CurMask);

  return true;
}


SCAN_CODE ScanTree::FindProc(FindData *FD)
{
  if (*CurMask==0)
    return SCAN_NEXT;
  bool FastFindFile=false;
  
  if (FindStack[Depth]==NULL) // No FindFile object for this depth yet.
  {
    bool Wildcards=IsWildcard(CurMask);

    // If we have a file name without wildcards, we can try to use
    // FastFind to optimize speed. For example, in Unix it results in
    // stat call instead of opendir/readdir/closedir.
    bool FindCode=!Wildcards && FindFile::FastFind(CurMask,FD,GetLinks);

    // Link check is important for NTFS, where links can have "Directory"
    // attribute, but we do not want to recurse to them in "get links" mode.
    bool IsDir=FindCode && FD->IsDir && (!GetLinks || !FD->IsLink);

    // SearchAll means that we'll use "*" mask for search, so we'll find
    // subdirectories and will be able to recurse into them.
    // We do not use "*" for directories at any level or for files
    // at top level in recursion mode.
    bool SearchAll=!IsDir && (Depth>0 || Recurse==RECURSE_ALWAYS ||
                   Wildcards && Recurse==RECURSE_WILDCARDS || 
                   ScanEntireDisk && Recurse!=RECURSE_DISABLE);
    if (Depth==0)
      SearchAllInRoot=SearchAll;
    if (SearchAll || Wildcards)
    {
      // Create the new FindFile object for wildcard based search.
      FindStack[Depth]=new FindFile;

      wchar SearchMask[NM];
      wcsncpyz(SearchMask,CurMask,ASIZE(SearchMask));
      if (SearchAll)
        SetName(SearchMask,MASKALL,ASIZE(SearchMask));
      FindStack[Depth]->SetMask(SearchMask);
    }
    else
    {
      // Either we failed to fast find or we found a file or we found
      // a directory in RECURSE_DISABLE mode, so we do not need to scan it.
      // We can return here and do not need to process further.
      // We need to process further only if we fast found a directory.
      if (!FindCode || !IsDir || Recurse==RECURSE_DISABLE)
      {
         // Return SCAN_SUCCESS if we found a file.
        SCAN_CODE RetCode=SCAN_SUCCESS;

        if (!FindCode)
        {
          // Return SCAN_ERROR if problem is more serious than just
          // "file not found".
          RetCode=FD->Error ? SCAN_ERROR:SCAN_NEXT;

          // If we failed to find an object, but our current mask is excluded,
          // we skip this object and avoid indicating an error.
          if (Cmd!=NULL && Cmd->ExclCheck(CurMask,false,true,true))
            RetCode=SCAN_NEXT;
          else
            ErrHandler.OpenErrorMsg(ErrArcName,CurMask);
        }

        // If we searched only for one file or directory in "fast find" 
        // (without a wildcard) mode, let's set masks to zero, 
        // so calling function will know that current mask is used 
        // and next one must be read from mask list for next call.
        // It is not necessary for directories, because even in "fast find"
        // mode, directory recursing will quit by (Depth < 0) condition,
        // which returns SCAN_DONE to calling function.
        *CurMask=0;

        return RetCode;
      }

      // We found a directory using only FindFile::FastFind function.
      FastFindFile=true;
    }
  }

  if (!FastFindFile && !FindStack[Depth]->Next(FD,GetLinks))
  {
    // We cannot find anything more in directory either because of
    // some error or just as result of all directory entries already read.

    bool Error=FD->Error;
    if (Error)
      ScanError(Error);

    wchar DirName[NM];
    *DirName=0;

    // Going to at least one directory level higher.
    delete FindStack[Depth];
    FindStack[Depth--]=NULL;
    while (Depth>=0 && FindStack[Depth]==NULL)
      Depth--;
    if (Depth < 0)
    {
      // Directories scanned both in normal and FastFindFile mode,
      // finally exit from scan here, by (Depth < 0) condition.

      if (Error)
        Errors++;
      return SCAN_DONE;
    }

    wchar *Slash=wcsrchr(CurMask,CPATHDIVIDER);
    if (Slash!=NULL)
    {
      wchar Mask[NM];
      wcscpy(Mask,Slash);
      if (Depth<SetAllMaskDepth)
        wcscpy(Mask+1,PointToName(OrigCurMask));
      *Slash=0;
      wcscpy(DirName,CurMask);
      wchar *PrevSlash=wcsrchr(CurMask,CPATHDIVIDER);
      if (PrevSlash==NULL)
        wcscpy(CurMask,Mask+1);
      else
        wcscpy(PrevSlash,Mask);
    }
    if (GetDirs==SCAN_GETDIRSTWICE &&
        FindFile::FastFind(DirName,FD,GetLinks) && FD->IsDir)
    {
      FD->Flags|=FDDF_SECONDDIR;
      return Error ? SCAN_ERROR:SCAN_SUCCESS;
    }
    return Error ? SCAN_ERROR:SCAN_NEXT;
  }

  // Link check is required for NTFS links, not for Unix.
  if (FD->IsDir && (!GetLinks || !FD->IsLink))
  {
    // If we found the directory in top (Depth==0) directory
    // and if we are not in "fast find" (directory name only as argument)
    // or in recurse (SearchAll was set when opening the top directory) mode,
    // we do not recurse into this directory. We either return it by itself
    // or skip it.
    if (!FastFindFile && Depth==0 && !SearchAllInRoot)
      return GetDirs==SCAN_GETCURDIRS ? SCAN_SUCCESS:SCAN_NEXT;

    // Let's check if directory name is excluded, so we do not waste
    // time searching in directory, which will be excluded anyway.
    if (Cmd!=NULL && (Cmd->ExclCheck(FD->Name,true,false,false) ||
        Cmd->ExclDirByAttr(FD->FileAttr)))
    {
      // If we are here in "fast find" mode, it means that entire directory
      // specified in command line is excluded. Then we need to return
      // SCAN_DONE to go to next mask and avoid the infinite loop
      // in GetNext() function. Such loop would be possible in case of
      // SCAN_NEXT code and "rar a arc dir -xdir" command.

      return FastFindFile ? SCAN_DONE:SCAN_NEXT;
    }
    
    wchar Mask[NM];

    wcscpy(Mask,FastFindFile ? MASKALL:PointToName(CurMask));
    wcscpy(CurMask,FD->Name);

    if (wcslen(CurMask)+wcslen(Mask)+1>=NM || Depth>=MAXSCANDEPTH-1)
    {
      uiMsg(UIERROR_PATHTOOLONG,CurMask,SPATHDIVIDER,Mask);
      return SCAN_ERROR;
    }

    AddEndSlash(CurMask,ASIZE(CurMask));
    wcsncatz(CurMask,Mask,ASIZE(CurMask));

    Depth++;

    // We need to use OrigCurMask for depths less than SetAllMaskDepth
    // and "*" for depths equal or larger than SetAllMaskDepth.
    // It is important when "fast finding" directories at Depth > 0.
    // For example, if current directory is RootFolder and we compress
    // the following directories structure:
    //   RootFolder
    //     +--Folder1
    //     |  +--Folder2
    //     |  +--Folder3
    //     +--Folder4
    // with 'rar a -r arcname Folder2' command, rar could add not only
    // Folder1\Folder2 contents, but also Folder1\Folder3 if we were using
    // "*" mask at all levels. We need to use "*" mask inside of Folder2,
    // but return to "Folder2" mask when completing scanning Folder2.
    // We can rewrite SearchAll expression above to avoid fast finding
    // directories at Depth > 0, but then 'rar a -r arcname Folder2'
    // will add the empty Folder2 and do not add its contents.

    if (FastFindFile)
      SetAllMaskDepth=Depth;
  }
  if (!FastFindFile && !CmpName(CurMask,FD->Name,MATCH_NAMES))
    return SCAN_NEXT;

  return SCAN_SUCCESS;
}


void ScanTree::ScanError(bool &Error)
{
#ifdef _WIN_ALL
  if (Error)
  {
    // Get attributes of parent folder and do not display an error
    // if it is reparse point. We cannot scan contents of standard
    // Windows reparse points like "C:\Documents and Settings"
    // and we do not want to issue numerous useless errors for them.
    // We cannot just check FD->FileAttr here, it can be undefined
    // if we process "folder\*" mask or if we process "folder" mask,
    // but "folder" is inaccessible.
    wchar *Slash=PointToName(CurMask);
    if (Slash>CurMask)
    {
      *(Slash-1)=0;
      DWORD Attr=GetFileAttributes(CurMask);
      *(Slash-1)=CPATHDIVIDER;
      if (Attr!=0xffffffff && (Attr & FILE_ATTRIBUTE_REPARSE_POINT)!=0)
        Error=false;
    }

    // Do not display an error if we cannot scan contents of
    // "System Volume Information" folder. Normally it is not accessible.
    if (wcsstr(CurMask,L"System Volume Information\\")!=NULL)
      Error=false;
  }
#endif

  if (Error && Cmd!=NULL && Cmd->ExclCheck(CurMask,false,true,true))
    Error=false;

  if (Error)
  {
    wchar FullName[NM];
    // This conversion works for wildcard masks too.
    ConvertNameToFull(CurMask,FullName,ASIZE(FullName));
    uiMsg(UIERROR_DIRSCAN,FullName);
    ErrHandler.SysErrMsg();
  }
}