methods/gzip.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: gzip.cc,v 1.17.2.1 2004/01/16 18:58:50 mdz Exp $
   4 /* ######################################################################
   5
   6    GZip method - Take a file URI in and decompress it into the target
   7    file.
   8
   9    ##################################################################### */
  10                                                                         /*}}}*/
  11 // Include Files                                                        /*{{{*/
  12 #include <config.h>
  13
  14 #include <apt-pkg/fileutl.h>
  15 #include <apt-pkg/error.h>
  16 #include <apt-pkg/acquire-method.h>
  17 #include <apt-pkg/strutl.h>
  18 #include <apt-pkg/hashes.h>
  19
  20 #include <sys/stat.h>
  21 #include <unistd.h>
  22 #include <utime.h>
  23 #include <stdio.h>
  24 #include <errno.h>
  25 #include <apti18n.h>
  26                                                                         /*}}}*/
  27
  28 const char *Prog;
  29
  30 class GzipMethod : public pkgAcqMethod
  31 {
  32    virtual bool Fetch(FetchItem *Itm);
  33
  34    public:
  35
  36    GzipMethod() : pkgAcqMethod("1.1",SingleInstance | SendConfig) {};
  37 };
  38
  39
  40 // GzipMethod::Fetch - Decompress the passed URI                        /*{{{*/
  41 // ---------------------------------------------------------------------
  42 /* */
  43 bool GzipMethod::Fetch(FetchItem *Itm)
  44 {
  45    URI Get = Itm->Uri;
  46    std::string Path = Get.Host + Get.Path; // To account for relative paths
  47
  48    FetchResult Res;
  49    Res.Filename = Itm->DestFile;
  50    URIStart(Res);
  51
  52    std::vector<APT::Configuration::Compressor> const compressors = APT::Configuration::getCompressors();
  53    std::vector<APT::Configuration::Compressor>::const_iterator compressor = compressors.begin();
  54    for (; compressor != compressors.end(); ++compressor)
  55       if (compressor->Name == Prog)
  56          break;
  57    if (compressor == compressors.end())
  58       return _error->Error("Extraction of file %s requires unknown compressor %s", Path.c_str(), Prog);
  59
  60    // Open the source and destination files
  61    FileFd From;
  62    From.Open(Path, FileFd::ReadOnly, *compressor);
  63
  64    if(From.FileSize() == 0)
  65       return _error->Error(_("Empty files can't be valid archives"));
  66
  67    FileFd To(Itm->DestFile,FileFd::WriteAtomic);
  68    To.EraseOnFailure();
  69    if (_error->PendingError() == true)
  70       return false;
  71
  72    // Read data from source, generate checksums and write
  73    Hashes Hash;
  74    bool Failed = false;
  75    while (1)
  76    {
  77       unsigned char Buffer[4*1024];
  78       unsigned long long Count = 0;
  79
  80       if (!From.Read(Buffer,sizeof(Buffer),&Count))
  81       {
  82          To.OpFail();
  83          return false;
  84       }
  85       if (Count == 0)
  86          break;
  87
  88       Hash.Add(Buffer,Count);
  89       if (To.Write(Buffer,Count) == false)
  90       {
  91          Failed = true;
  92          break;
  93       }
  94    }
  95
  96    From.Close();
  97    To.Close();
  98
  99    if (Failed == true)
 100       return false;
 101
 102    // Transfer the modification times
 103    struct stat Buf;
 104    if (stat(Path.c_str(),&Buf) != 0)
 105       return _error->Errno("stat",_("Failed to stat"));
 106
 107    struct utimbuf TimeBuf;
 108    TimeBuf.actime = Buf.st_atime;
 109    TimeBuf.modtime = Buf.st_mtime;
 110    if (utime(Itm->DestFile.c_str(),&TimeBuf) != 0)
 111       return _error->Errno("utime",_("Failed to set modification time"));
 112
 113    if (stat(Itm->DestFile.c_str(),&Buf) != 0)
 114       return _error->Errno("stat",_("Failed to stat"));
 115
 116    // Return a Done response
 117    Res.LastModified = Buf.st_mtime;
 118    Res.Size = Buf.st_size;
 119    Res.TakeHashes(Hash);
 120
 121    URIDone(Res);
 122
 123    return true;
 124 }
 125                                                                         /*}}}*/
 126
 127 int main(int argc, char *argv[])
 128 {
 129    setlocale(LC_ALL, "");
 130
 131    Prog = strrchr(argv[0],'/');
 132    ++Prog;
 133
 134    GzipMethod Mth;
 135    return Mth.Run();
 136 }