include/unotools/tempfile.hxx

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  19
  20 #ifndef INCLUDED_UNOTOOLS_TEMPFILE_HXX
  21 #define INCLUDED_UNOTOOLS_TEMPFILE_HXX
  22
  23 #include <unotools/unotoolsdllapi.h>
  24 #include <tools/stream.hxx>
  25 #include <memory>
  26
  27 namespace utl
  28 {
  29
  30 /**
  31     The class TempFile gives access to temporary files in the local file system. Sometimes they are needed because a 3rd party
  32     code has a file name based interface, or some file access has to be done locally without transferring tons of bytes to or
  33     from a remote system.
  34     Creating a UCB content on a TempFile is only possible if a UCP for the local file system is present.
  35     TempFiles can always be accessed by SvFileStreams or Sot/SvStorages using the "physical" file name ( not the URL, because
  36     this may be a non-file URL, see below ), but if a UCB content can be created, it is also possible to take the URL and use
  37     the UCB helper classes for streams. For convenience use UcbStreamHelper.
  38     A Tempfile always has a "physical" file name ( a file name in the local computers host notation ) but it has a
  39     "UCB compatible" URL only if a UCP for the local file system exists. This URL may have its own URL scheme
  40     ( not necessarily "file://" ! ). The TempFile class methods take this into account, but other simple conversions like
  41     the osl functions do not.
  42     So it is a potential error to convert between the filename and the URL of a TempFile object using functions or methods
  43     outside this class.
  44 */
  45
  46 class UNOTOOLS_DLLPUBLIC TempFile
  47 {
  48     OUString    aName;
  49     std::unique_ptr<SvStream>
  50                 pStream;
  51     bool const        bIsDirectory;
  52     bool        bKillingFileEnabled;
  53
  54 public:
  55                     /**
  56                     Create a temporary file or directory, in the default tempfile folder or if possible in a given folder.
  57                     This given folder ( the "parent" parameter ( if not NULL ) ) must be a "UCB compatible" URL.
  58                     The temporary object is created in the local file system, even if there is no UCB that can access it.
  59                     If the given folder is part of the local file system, the TempFile is created in this folder.
  60                     */
  61                     TempFile( const OUString* pParent=nullptr, bool bDirectory=false );
  62
  63                     /**
  64                     Same as above; additionally the name starts with some given characters followed by a counter ( example:
  65                     rLeadingChars="abc" means "abc0","abc1" and so on, depending on existing files in the folder ).
  66                     The extension string may be f.e. ".txt" or "", if no extension string is given, ".tmp" is used
  67                         @param  _bStartWithZero If set to false names will be generated like "abc","abc0","abc1"
  68                         @param  bCreateParentDirs If rLeadingChars contains a slash, this will create the required
  69                                 parent directories.
  70                     */
  71                     TempFile( const OUString& rLeadingChars, bool _bStartWithZero=true, const OUString* pExtension=nullptr,
  72                               const OUString* pParent=nullptr, bool bCreateParentDirs=false );
  73
  74                     TempFile(TempFile && other) noexcept;
  75
  76                     /**
  77                     TempFile will be removed from disk in dtor if EnableKillingFile(true) was called before.
  78                     Temporary directories will be removed recursively in that case.
  79                     */
  80                     ~TempFile();
  81
  82                     /**
  83                     Returns sal_True if it has a valid file name.
  84                     */
  85     bool            IsValid() const;
  86
  87                     /**
  88                     Returns the URL of the tempfile object.
  89                     If you want to have the system path file name, use the GetFileName() method of this object
  90                     */
  91     OUString const & GetURL() const;
  92
  93                     /**
  94                     Returns the system path name of the tempfile in host notation
  95                     If you want to have the URL, use the GetURL() method of this object.
  96                     */
  97     OUString        GetFileName() const;
  98
  99                     /**
 100                     Returns a stream to the tempfiles data; the stream is owned by the tempfile object, so you have to keep this
 101                     alive as long as you want to use the stream. If the TempFile object is destroyed, it also destroys the
 102                     stream object, the underlying file is only deleted if EnableKillingFile(true) has been called before!
 103                     */
 104     SvStream*       GetStream( StreamMode eMode );
 105
 106                     /**
 107                     Let the TempFile object close and destroy the owned stream object if any.
 108                     */
 109     void            CloseStream();
 110
 111                     /**
 112                     If enabled the file will be removed from disk when the dtor is called ( default is not enabled )
 113                     */
 114     void            EnableKillingFile( bool bEnable=true )
 115                     { bKillingFileEnabled = bEnable; }
 116
 117                     /**
 118                     Only create a "physical" file name for a temporary file that would be valid at that moment.
 119                     Should only be used for 3rd party code with a file name interface that wants to create the file by itself.
 120                     If you want to convert file name into a URL, always use class LocalFileHelper, but never use any
 121                     conversion functions of osl.
 122                     */
 123     static OUString CreateTempName();
 124
 125                     /**
 126                     The TempNameBaseDirectory is a subfolder in the folder that is passed as a "physical" file name in the
 127                     SetTempNameBaseDirectory method.
 128                     This subfolder will be used if a TempFile or TempName is created without a parent name or a parent name
 129                     that does not belong to the local file system.
 130                     The caller of the SetTempNameBase is responsible for deleting this folder and all temporary files in it.
 131                     The return value of both methods is the complete "physical" name of the tempname base folder.
 132                     It is not a URL because all URLs must be "UCB compatible", so there may be no suitable URL at all.
 133                     */
 134     static OUString SetTempNameBaseDirectory( const OUString &rBaseName );
 135
 136     // Return the URL of the temp directory (the one set with SetTempNameBaseDirectory or the
 137     // default tempfile folder):
 138     static OUString GetTempNameBaseDirectory();
 139 };
 140
 141 }
 142
 143 #endif
 144
 145 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */