methods/gzip.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: gzip.cc,v 1.6 1998/11/11 06:54:19 jgg 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 <strutl.h>
  16
  17 #include <sys/stat.h>
  18 #include <unistd.h>
  19 #include <utime.h>
  20 #include <wait.h>
  21 #include <stdio.h>
  22                                                                         /*}}}*/
  23
  24 class GzipMethod : public pkgAcqMethod
  25 {
  26    virtual bool Fetch(FetchItem *Itm);
  27
  28    public:
  29
  30    GzipMethod() : pkgAcqMethod("1.0",SingleInstance | SendConfig) {};
  31 };
  32
  33 // GzipMethod::Fetch - Decompress the passed URI                        /*{{{*/
  34 // ---------------------------------------------------------------------
  35 /* */
  36 bool GzipMethod::Fetch(FetchItem *Itm)
  37 {
  38    URI Get = Itm->Uri;
  39
  40    FetchResult Res;
  41    Res.Filename = Itm->DestFile;
  42    URIStart(Res);
  43
  44    // Open the source and destintation files
  45    FileFd From(Get.Path,FileFd::ReadOnly);
  46    FileFd To(Itm->DestFile,FileFd::WriteEmpty);
  47    To.EraseOnFailure();
  48    if (_error->PendingError() == true)
  49       return false;
  50
  51    // Fork gzip
  52    int Process = fork();
  53    if (Process < 0)
  54       return _error->Errno("fork","Couldn't fork gzip");
  55
  56    // The child
  57    if (Process == 0)
  58    {
  59       dup2(From.Fd(),STDIN_FILENO);
  60       dup2(To.Fd(),STDOUT_FILENO);
  61       From.Close();
  62       To.Close();
  63       SetCloseExec(STDIN_FILENO,false);
  64       SetCloseExec(STDOUT_FILENO,false);
  65
  66       const char *Args[3];
  67       Args[0] = _config->Find("Dir::bin::gzip","gzip").c_str();
  68       Args[1] = "-d";
  69       Args[2] = 0;
  70       execvp(Args[0],(char **)Args);
  71       exit(100);
  72    }
  73    From.Close();
  74
  75    // Wait for gzip to finish
  76    int Status;
  77    if (waitpid(Process,&Status,0) != Process)
  78    {
  79       To.OpFail();
  80       return _error->Errno("wait","Waiting for gzip failed");
  81    }
  82
  83    if (WIFEXITED(Status) == 0 || WEXITSTATUS(Status) != 0)
  84    {
  85       To.OpFail();
  86       return _error->Error("gzip failed, perhaps the disk is full or the directory permissions are wrong.");
  87    }
  88
  89    To.Close();
  90
  91    // Transfer the modification times
  92    struct stat Buf;
  93    if (stat(Get.Path.c_str(),&Buf) != 0)
  94       return _error->Errno("stat","Failed to stat");
  95
  96    struct utimbuf TimeBuf;
  97    TimeBuf.actime = Buf.st_atime;
  98    TimeBuf.modtime = Buf.st_mtime;
  99    if (utime(Itm->DestFile.c_str(),&TimeBuf) != 0)
 100       return _error->Errno("utime","Failed to set modification time");
 101
 102    // Return a Done response
 103    Res.LastModified = Buf.st_mtime;
 104    URIDone(Res);
 105
 106    return true;
 107 }
 108                                                                         /*}}}*/
 109
 110 int main()
 111 {
 112    GzipMethod Mth;
 113    return Mth.Run();
 114 }