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