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 <apt-pkg/fileutl.h>
  13 #include <apt-pkg/error.h>
  14 #include <apt-pkg/acquire-method.h>
  15 #include <apt-pkg/strutl.h>
  16 #include <apt-pkg/hashes.h>
  17
  18 #include <sys/stat.h>
  19 #include <unistd.h>
  20 #include <utime.h>
  21 #include <stdio.h>
  22 #include <errno.h>
  23 #include <apti18n.h>
  24                                                                         /*}}}*/
  25
  26 class GzipMethod : public pkgAcqMethod
  27 {
  28    virtual bool Fetch(FetchItem *Itm);
  29
  30    public:
  31
  32    GzipMethod() : pkgAcqMethod("1.1",SingleInstance | SendConfig) {};
  33 };
  34
  35
  36 // GzipMethod::Fetch - Decompress the passed URI                        /*{{{*/
  37 // ---------------------------------------------------------------------
  38 /* */
  39 bool GzipMethod::Fetch(FetchItem *Itm)
  40 {
  41    URI Get = Itm->Uri;
  42    string Path = Get.Host + Get.Path; // To account for relative paths
  43
  44    FetchResult Res;
  45    Res.Filename = Itm->DestFile;
  46    URIStart(Res);
  47
  48    // Open the source and destination files
  49    FileFd From(Path,FileFd::ReadOnlyGzip);
  50
  51    // if the file is empty, just rename it and return
  52    if(From.Size() == 0)
  53    {
  54       rename(Path.c_str(), Itm->DestFile.c_str());
  55       return true;
  56    }
  57
  58    FileFd To(Itm->DestFile,FileFd::WriteAtomic);
  59    To.EraseOnFailure();
  60    if (_error->PendingError() == true)
  61       return false;
  62
  63    // Read data from source, generate checksums and write
  64    Hashes Hash;
  65    bool Failed = false;
  66    while (1)
  67    {
  68       unsigned char Buffer[4*1024];
  69       unsigned long Count;
  70
  71       if (!From.Read(Buffer,sizeof(Buffer),&Count))
  72       {
  73          To.OpFail();
  74          return false;
  75       }
  76       if (Count == 0)
  77          break;
  78
  79       Hash.Add(Buffer,Count);
  80       if (To.Write(Buffer,Count) == false)
  81       {
  82          Failed = true;
  83          break;
  84       }
  85    }
  86
  87    From.Close();
  88    To.Close();
  89
  90    if (Failed == true)
  91       return false;
  92
  93    // Transfer the modification times
  94    struct stat Buf;
  95    if (stat(Path.c_str(),&Buf) != 0)
  96       return _error->Errno("stat",_("Failed to stat"));
  97
  98    struct utimbuf TimeBuf;
  99    TimeBuf.actime = Buf.st_atime;
 100    TimeBuf.modtime = Buf.st_mtime;
 101    if (utime(Itm->DestFile.c_str(),&TimeBuf) != 0)
 102       return _error->Errno("utime",_("Failed to set modification time"));
 103
 104    if (stat(Itm->DestFile.c_str(),&Buf) != 0)
 105       return _error->Errno("stat",_("Failed to stat"));
 106
 107    // Return a Done response
 108    Res.LastModified = Buf.st_mtime;
 109    Res.Size = Buf.st_size;
 110    Res.TakeHashes(Hash);
 111
 112    URIDone(Res);
 113
 114    return true;
 115 }
 116                                                                         /*}}}*/
 117
 118 int main(int argc, char *argv[])
 119 {
 120    setlocale(LC_ALL, "");
 121
 122    GzipMethod Mth;
 123    return Mth.Run();
 124 }