apt-pkg/contrib/fileutl.h

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: fileutl.h,v 1.26 2001/05/07 05:06:52 jgg Exp $
   4 /* ######################################################################
   5
   6    File Utilities
   7
   8    CopyFile - Buffered copy of a single file
   9    GetLock - dpkg compatible lock file manipulation (fcntl)
  10    FileExists - Returns true if the file exists
  11    SafeGetCWD - Returns the CWD in a string with overrun protection
  12
  13    The file class is a handy abstraction for various functions+classes
  14    that need to accept filenames.
  15
  16    This source is placed in the Public Domain, do with it what you will
  17    It was originally written by Jason Gunthorpe.
  18
  19    ##################################################################### */
  20                                                                         /*}}}*/
  21 #ifndef PKGLIB_FILEUTL_H
  22 #define PKGLIB_FILEUTL_H
  23
  24 #include <apt-pkg/macros.h>
  25
  26 #include <string>
  27 #include <vector>
  28
  29 #include <zlib.h>
  30
  31 /* Define this for python-apt */
  32 #define APT_HAS_GZIP 1
  33
  34 using std::string;
  35
  36 class FileFd
  37 {
  38    protected:
  39    int iFd;
  40
  41    enum LocalFlags {AutoClose = (1<<0),Fail = (1<<1),DelOnFail = (1<<2),
  42                     HitEof = (1<<3), Replace = (1<<4) };
  43    unsigned long Flags;
  44    string FileName;
  45    string TemporaryFileName;
  46    gzFile gz;
  47
  48    public:
  49    enum OpenMode {ReadOnly,WriteEmpty,WriteExists,WriteAny,WriteTemp,ReadOnlyGzip,
  50                   WriteAtomic};
  51
  52    inline bool Read(void *To,unsigned long long Size,bool AllowEof)
  53    {
  54       unsigned long long Jnk;
  55       if (AllowEof)
  56          return Read(To,Size,&Jnk);
  57       return Read(To,Size);
  58    }
  59    bool Read(void *To,unsigned long long Size,unsigned long long *Actual = 0);
  60    bool Write(const void *From,unsigned long long Size);
  61    bool Seek(unsigned long long To);
  62    bool Skip(unsigned long long To);
  63    bool Truncate(unsigned long long To);
  64    unsigned long long Tell();
  65    unsigned long long Size();
  66    unsigned long long FileSize();
  67
  68    /* You want to use 'unsigned long long' if you are talking about a file
  69       to be able to support large files (>2 or >4 GB) properly.
  70       This shouldn't happen all to often for the indexes, but deb's might be…
  71       And as the auto-conversation converts a 'unsigned long *' to a 'bool'
  72       instead of 'unsigned long long *' we need to provide this explicitely -
  73       otherwise applications magically start to fail… */
  74    __deprecated bool Read(void *To,unsigned long long Size,unsigned long *Actual)
  75    {
  76         unsigned long long R;
  77         bool const T = Read(To, Size, &R);
  78         *Actual = R;
  79         return T;
  80    }
  81
  82    bool Open(string FileName,OpenMode Mode,unsigned long Perms = 0666);
  83    bool OpenDescriptor(int Fd, OpenMode Mode, bool AutoClose=false);
  84    bool Close();
  85    bool Sync();
  86
  87    // Simple manipulators
  88    inline int Fd() {return iFd;};
  89    inline void Fd(int fd) {iFd = fd;};
  90    inline gzFile gzFd() {return gz;};
  91    inline bool IsOpen() {return iFd >= 0;};
  92    inline bool Failed() {return (Flags & Fail) == Fail;};
  93    inline void EraseOnFailure() {Flags |= DelOnFail;};
  94    inline void OpFail() {Flags |= Fail;};
  95    inline bool Eof() {return (Flags & HitEof) == HitEof;};
  96    inline string &Name() {return FileName;};
  97
  98    FileFd(string FileName,OpenMode Mode,unsigned long Perms = 0666) : iFd(-1),
  99             Flags(0), gz(NULL)
 100    {
 101       Open(FileName,Mode,Perms);
 102    };
 103    FileFd(int Fd = -1) : iFd(Fd), Flags(AutoClose), gz(NULL) {};
 104    FileFd(int Fd,bool) : iFd(Fd), Flags(0), gz(NULL) {};
 105    virtual ~FileFd();
 106 };
 107
 108 bool RunScripts(const char *Cnf);
 109 bool CopyFile(FileFd &From,FileFd &To);
 110 int GetLock(string File,bool Errors = true);
 111 bool FileExists(string File);
 112 bool RealFileExists(string File);
 113 bool DirectoryExists(string const &Path) __attrib_const;
 114 bool CreateDirectory(string const &Parent, string const &Path);
 115 time_t GetModificationTime(string const &Path);
 116
 117 /** \brief Ensure the existence of the given Path
 118  *
 119  *  \param Parent directory of the Path directory - a trailing
 120  *  /apt/ will be removed before CreateDirectory call.
 121  *  \param Path which should exist after (successful) call
 122  */
 123 bool CreateAPTDirectoryIfNeeded(string const &Parent, string const &Path);
 124
 125 std::vector<string> GetListOfFilesInDir(string const &Dir, string const &Ext,
 126                                         bool const &SortList, bool const &AllowNoExt=false);
 127 std::vector<string> GetListOfFilesInDir(string const &Dir, std::vector<string> const &Ext,
 128                                         bool const &SortList);
 129 string SafeGetCWD();
 130 void SetCloseExec(int Fd,bool Close);
 131 void SetNonBlock(int Fd,bool Block);
 132 bool WaitFd(int Fd,bool write = false,unsigned long timeout = 0);
 133 pid_t ExecFork();
 134 bool ExecWait(pid_t Pid,const char *Name,bool Reap = false);
 135
 136 // File string manipulators
 137 string flNotDir(string File);
 138 string flNotFile(string File);
 139 string flNoLink(string File);
 140 string flExtension(string File);
 141 string flCombine(string Dir,string File);
 142
 143 #endif