    // @(#)root/rfio:$Name:  $:$Id: TRFIOFile.cxx,v 1.32 2005/02/28 17:28:12 rdm Exp $
    // Author: Fons Rademakers   20/01/99

    /*************************************************************************
     * Copyright (C) 1995-2000, Rene Brun and Fons Rademakers.               *
     * All rights reserved.                                                  *
     *                                                                       *
     * For the licensing terms see $ROOTSYS/LICENSE.                         *
     * For the list of contributors see $ROOTSYS/README/CREDITS.             *
     *************************************************************************/

    //////////////////////////////////////////////////////////////////////////
    //                                                                      //
    // TRFIOFile                                                            //
    //                                                                      //
    // A TRFIOFile is like a normal TFile except that it reads and writes   //
    // its data via a rfiod server (for more on the rfiod daemon see        //
    // http://wwwinfo.cern.ch/pdp/serv/shift.html). TRFIOFile file names    //
    // are in standard URL format with protocol "rfio". The following are   //
    // valid TRFIOFile URL's:                                               //
    //                                                                      //
    //    rfio:/afs/cern.ch/user/r/rdm/galice.root                          //
    //         where galice.root is a symlink of the type /shift/.../...    //
    //    rfio:na49db1:/data1/raw.root                                      //
    //                                                                      //
    //////////////////////////////////////////////////////////////////////////

    #include "TRFIOFile.h"
    #include "TROOT.h"
    #include <sys/stat.h>
    #include <sys/types.h>
    #ifndef R__WIN32
    #include <unistd.h>
    #if defined(R__SUN) || defined(R__SGI) || defined(R__HPUX) || \
        defined(R__AIX) || defined(R__LINUX) || defined(R__SOLARIS) || \
        defined(R__ALPHA) || defined(R__HIUX) || defined(R__FBSD) || \
        defined(R__MACOSX) || defined(R__HURD) || defined(R__OBSD)
    #define HAS_DIRENT
    #endif
    #endif

    #ifdef HAS_DIRENT
    #include <dirent.h>
    #else
    struct dirent {
       ino_t d_ino;
       off_t d_reclen;
       unsigned short d_namlen;
       char d_name[232];  // from Castor_limits.h
    };
    #endif

    extern "C" {
       int   rfio_open(const char *filepath, int flags, int mode);
       int   rfio_close(int s);
       int   rfio_read(int s, void *ptr, int size);
       int   rfio_write(int s, const void *ptr, int size);
       int   rfio_lseek(int s, int offset, int how);
       int   rfio_access(const char *filepath, int mode);
       int   rfio_unlink(const char *filepath);
       int   rfio_parse(const char *name, char **host, char **path);
       int   rfio_stat(const char *path, struct stat *statbuf);
       int   rfio_fstat(int s, struct stat *statbuf);
       void  rfio_perror(const char *msg);
       char *rfio_serror();
       int   rfiosetopt(int opt, int *pval, int len);
       int   rfio_mkdir(const char *path, int mode);
       void *rfio_opendir(const char *dirpath);
       int   rfio_closedir(void *dirp);
       void *rfio_readdir(void *dirp);
    #ifdef R__WIN32
       int  *C__serrno(void);
       int  *C__rfio_errno (void);
    #endif
    };

    #ifndef RFIO_READOPT
    #define RFIO_READOPT 1
    #endif

    #ifdef R__WIN32

    // Thread safe rfio_errno. Note, C__rfio_errno is defined in Cglobals.c rather
    // than rfio/error.c.
    #define rfio_errno (*C__rfio_errno())

    // Thread safe serrno. Note, C__serrno is defined in Cglobals.c rather
    // rather than serror.c.
    #define serrno (*C__serrno())

    #else

    extern int rfio_errno;
    extern int serrno;

    #endif

    ClassImp(TRFIOFile)
    ClassImp(TRFIOSystem)

    //______________________________________________________________________________
     TRFIOFile::TRFIOFile(const char *url, Option_t *option, const char *ftitle,
                         Int_t compress)
             : TFile(url, "NET", ftitle, compress), fUrl(url)
    {
       // Create a RFIO file object. A RFIO file is the same as a TFile
       // except that it is being accessed via a rfiod server. The url
       // argument must be of the form: rfio:/path/file.root (where file.root
       // is a symlink of type /shift/aaa/bbb/ccc) or rfio:server:/path/file.root.
       // If the file specified in the URL does not exist, is not accessable
       // or can not be created the kZombie bit will be set in the TRFIOFile
       // object. Use IsZombie() to see if the file is accessable.
       // For a description of the option and other arguments see the TFile ctor.
       // The preferred interface to this constructor is via TFile::Open().

       fOption = option;
       fOption.ToUpper();

       // tell RFIO to not read large buffers, ROOT does own buffering
       Int_t readopt = 0;
       ::rfiosetopt(RFIO_READOPT, &readopt, 4);

       if (fOption == "NEW")
          fOption = "CREATE";

       Bool_t create   = (fOption == "CREATE") ? kTRUE : kFALSE;
       Bool_t recreate = (fOption == "RECREATE") ? kTRUE : kFALSE;
       Bool_t update   = (fOption == "UPDATE") ? kTRUE : kFALSE;
       Bool_t read     = (fOption == "READ") ? kTRUE : kFALSE;
       if (!create && !recreate && !update && !read) {
          read    = kTRUE;
          fOption = "READ";
       }

       TString stmp;
       char *fname;
       if ((fname = gSystem->ExpandPathName(fUrl.GetFile()))) {
          if (!strstr(fname, ":/")) {
             char *host;
             char *name;
             if (::rfio_parse(fname, &host, &name))
                stmp = Form("%s:%s", host, name);
             else
                stmp = fname;
          } else
             stmp = fname;
          delete [] fname;
          fname = (char *)stmp.Data();
       } else {
          Error("TRFIOFile", "error expanding path %s", fUrl.GetFile());
          goto zombie;
       }

       if (recreate) {
          if (::rfio_access(fname, kFileExists) == 0)
             ::rfio_unlink(fname);
          recreate = kFALSE;
          create   = kTRUE;
          fOption  = "CREATE";
       }
       if (create && ::rfio_access(fname, kFileExists) == 0) {
          Error("TRFIOFile", "file %s already exists", fname);
          goto zombie;
       }
       if (update) {
          if (::rfio_access(fname, kFileExists) != 0) {
             update = kFALSE;
             create = kTRUE;
          }
          if (update && ::rfio_access(fname, kWritePermission) != 0) {
             Error("TRFIOFile", "no write permission, could not open file %s", fname);
             goto zombie;
          }
       }
       if (read) {
          if (::rfio_access(fname, kFileExists) != 0) {
             Error("TRFIOFile", "file %s does not exist", fname);
             goto zombie;
          }
          if (::rfio_access(fname, kReadPermission) != 0) {
             Error("TRFIOFile", "no read permission, could not open file %s", fname);
             goto zombie;
          }
       }

       // Connect to file system stream
       fRealName = fname;

       if (create || update) {
    #ifndef WIN32
          fD = SysOpen(fname, O_RDWR | O_CREAT, 0644);
    #else
          fD = SysOpen(fname, O_RDWR | O_CREAT | O_BINARY, S_IREAD | S_IWRITE);
    #endif
          if (fD == -1) {
             SysError("TRFIOFile", "file %s can not be opened", fname);
             goto zombie;
          }
          fWritable = kTRUE;
       } else {
    #ifndef WIN32
          fD = SysOpen(fname, O_RDONLY, 0644);
    #else
          fD = SysOpen(fname, O_RDONLY | O_BINARY, S_IREAD | S_IWRITE);
    #endif
          if (fD == -1) {
             SysError("TRFIOFile", "file %s can not be opened for reading", fname);
             goto zombie;
          }
          fWritable = kFALSE;
       }

       Init(create);

       return;

    zombie:
       // error in file opening occured, make this object a zombie
       MakeZombie();
       gDirectory = gROOT;
    }

    //______________________________________________________________________________
     TRFIOFile::~TRFIOFile()
    {
       // RFIO file dtor. Close and flush directory structure.

       Close();
    }

    //______________________________________________________________________________
     Int_t TRFIOFile::SysOpen(const char *pathname, Int_t flags, UInt_t mode)
    {
       // Interface to system open. All arguments like in POSIX open.

       Int_t ret = ::rfio_open((char *)pathname, flags, (Int_t) mode);
       if (ret < 0)
          gSystem->SetErrorStr(::rfio_serror());
       return ret;
    }

    //______________________________________________________________________________
     Int_t TRFIOFile::SysClose(Int_t fd)
    {
       // Interface to system close. All arguments like in POSIX close.

       Int_t ret = ::rfio_close(fd);
       if (ret < 0)
          gSystem->SetErrorStr(::rfio_serror());
       return ret;
    }

    //______________________________________________________________________________
     Int_t TRFIOFile::SysRead(Int_t fd, void *buf, Int_t len)
    {
       // Interface to system read. All arguments like in POSIX read.

       fOffset += len;
       Int_t ret = ::rfio_read(fd, (char *)buf, len);
       if (ret < 0)
          gSystem->SetErrorStr(::rfio_serror());
       return ret;
    }

    //______________________________________________________________________________
     Int_t TRFIOFile::SysWrite(Int_t fd, const void *buf, Int_t len)
    {
       // Interface to system write. All arguments like in POSIX write.

       fOffset += len;
       Int_t ret = ::rfio_write(fd, (char *)buf, len);
       if (ret < 0)
          gSystem->SetErrorStr(::rfio_serror());
       return ret;
    }

    //______________________________________________________________________________
     Long64_t TRFIOFile::SysSeek(Int_t fd, Long64_t offset, Int_t whence)
    {
       // Interface to system lseek. All arguments like in POSIX lseek
       // except that the offset and return value are Long_t to be able to
       // handle 64 bit file systems.

       if (whence == SEEK_SET && offset == fOffset) return offset;

       Long64_t ret = ::rfio_lseek(fd, offset, whence);

       if (ret < 0)
          gSystem->SetErrorStr(::rfio_serror());
       else
          fOffset = ret;

       return ret;
    }

    //______________________________________________________________________________
     Int_t TRFIOFile::SysStat(Int_t fd, Long_t *id, Long64_t *size, Long_t *flags,
                             Long_t *modtime)
    {
       // Interface to TSystem:GetPathInfo(). Generally implemented via
       // stat() or fstat().

       struct stat statbuf;

       if (::rfio_fstat(fd, &statbuf) >= 0) {
          if (id)
             *id = (statbuf.st_dev << 24) + statbuf.st_ino;
          if (size)
             *size = statbuf.st_size;
          if (modtime)
             *modtime = statbuf.st_mtime;
          if (flags) {
             *flags = 0;
             if (statbuf.st_mode & ((S_IEXEC)|(S_IEXEC>>3)|(S_IEXEC>>6)))
                *flags |= 1;
             if ((statbuf.st_mode & S_IFMT) == S_IFDIR)
                *flags |= 2;
             if ((statbuf.st_mode & S_IFMT) != S_IFREG &&
                 (statbuf.st_mode & S_IFMT) != S_IFDIR)
                *flags |= 4;
          }
          return 0;
       }

       gSystem->SetErrorStr(::rfio_serror());
       return 1;
    }

    //______________________________________________________________________________
     Bool_t TRFIOFile::ReadBuffer(char *buf, Int_t len)
    {
       // Read specified byte range from remote file via rfiod daemon.
       // Returns kTRUE in case of error.

       if (fCache) {
          Int_t st;
          Long64_t off = GetRelOffset();
          if ((st = fCache->ReadBuffer(off, buf, len)) < 0) {
             Error("ReadBuffer", "error reading from cache");
             return kTRUE;
          }
          if (st > 0) {
             // fOffset might have been changed via TCache::ReadBuffer(), reset it
             Seek(off + len);
             return kFALSE;
          }
       }

       return TFile::ReadBuffer(buf, len);
    }

    //______________________________________________________________________________
     Bool_t TRFIOFile::WriteBuffer(const char *buf, Int_t len)
    {
       // Write specified byte range to remote file via rfiod daemon.
       // Returns kTRUE in case of error.

       if (!IsOpen() || !fWritable) return kTRUE;

       if (fCache) {
          Int_t st;
          Long64_t off = GetRelOffset();
          if ((st = fCache->WriteBuffer(off, buf, len)) < 0) {
             Error("WriteBuffer", "error writing to cache");
             return kTRUE;
          }
          if (st > 0) {
             // fOffset might have been changed via TCache::WriteBuffer(), reset it
             Seek(off + len);
             return kFALSE;
          }
       }

       return TFile::WriteBuffer(buf, len);
    }

    //______________________________________________________________________________
     Int_t TRFIOFile::GetErrno() const
    {
       // Method returning rfio_errno. For RFIO files must use this
       // function since we need to check rfio_errno then serrno and finally errno.

       if (rfio_errno)
          return rfio_errno;
       if (serrno)
          return serrno;
       return TSystem::GetErrno();
    }

    //______________________________________________________________________________
     void TRFIOFile::ResetErrno() const
    {
       // Method resetting the rfio_errno, serrno and errno.

       rfio_errno = 0;
       serrno = 0;
       TSystem::ResetErrno();
    }

    //______________________________________________________________________________
    TRFIOSystem::TRFIOSystem() : TSystem("-rfio", "RFIO Helper System")
    {
       // Create helper class that allows directory access via rfiod.

       // name must start with '-' to bypass the TSystem singleton check
       SetName("rfio");

       fDirp = 0;
    }

    //______________________________________________________________________________
    Int_t TRFIOSystem::MakeDirectory(const char *dir)
    {
       // Make a directory via rfiod.

       TUrl url(dir);

       Int_t ret = ::rfio_mkdir(url.GetFile(), 0755);
       if (ret < 0)
          gSystem->SetErrorStr(::rfio_serror());
       return ret;
    }

    //______________________________________________________________________________
    void *TRFIOSystem::OpenDirectory(const char *dir)
    {
       // Open a directory via rfiod. Returns an opaque pointer to a dir
       // structure. Returns 0 in case of error.

       if (fDirp) {
          Error("OpenDirectory", "invalid directory pointer (should never happen)");
          fDirp = 0;
       }

       TUrl url(dir);

       struct stat finfo;

       if (::rfio_stat(url.GetFile(), &finfo) < 0)
          return 0;

       if ((finfo.st_mode & S_IFMT) != S_IFDIR)
          return 0;

       fDirp = (void*) ::rfio_opendir(url.GetFile());

       if (!fDirp)
          gSystem->SetErrorStr(::rfio_serror());

       return fDirp;
    }

    //______________________________________________________________________________
    void TRFIOSystem::FreeDirectory(void *dirp)
    {
       // Free directory via rfiod.

       if (dirp != fDirp) {
          Error("FreeDirectory", "invalid directory pointer (should never happen)");
          return;
       }

       if (dirp)
          ::rfio_closedir(dirp);

       fDirp = 0;
    }

    //______________________________________________________________________________
    const char *TRFIOSystem::GetDirEntry(void *dirp)
    {
       // Get directory entry via rfiod. Returns 0 in case no more entries.

       if (dirp != fDirp) {
          Error("GetDirEntry", "invalid directory pointer (should never happen)");
          return 0;
       }

       struct dirent *dp;

       if (dirp) {
          dp = (struct dirent *) ::rfio_readdir(dirp);
          if (!dp)
             return 0;
          return dp->d_name;
       }
       return 0;
    }

    //______________________________________________________________________________
    Int_t TRFIOSystem::GetPathInfo(const char *path, FileStat_t &buf)
    {
       // Get info about a file. Info is returned in the form of a FileStat_t
       // structure (see TSystem.h).
       // The function returns 0 in case of success and 1 if the file could
       // not be stat'ed.

       TUrl url(path);

       struct stat sbuf;

       if (path && ::rfio_stat(url.GetFile(), &sbuf) >= 0) {

          buf.fDev    = sbuf.st_dev;
          buf.fIno    = sbuf.st_ino;
          buf.fMode   = sbuf.st_mode;
          buf.fUid    = sbuf.st_uid;
          buf.fGid    = sbuf.st_gid;
          buf.fSize   = sbuf.st_size;
          buf.fMtime  = sbuf.st_mtime;
          buf.fIsLink = kFALSE;

          return 0;
       }
       return 1;
    }

    //______________________________________________________________________________
    Bool_t TRFIOSystem::AccessPathName(const char *path, EAccessMode mode)
    {
       // Returns FALSE if one can access a file using the specified access mode.
       // Mode is the same as for the Unix access(2) function.
       // Attention, bizarre convention of return value!!

       TUrl url(path);

       if (::rfio_access(url.GetFile(), mode) == 0)
          return kFALSE;
       gSystem->SetErrorStr(::rfio_serror());
       return kTRUE;
    }