methods/gzip.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: gzip.cc,v 1.5 1998/11/05 07:21:47 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    // Open the source and destintation files
  41    FileFd From(Get.Path,FileFd::ReadOnly);
  42    FileFd To(Itm->DestFile,FileFd::WriteEmpty);
  43    To.EraseOnFailure();
  44    if (_error->PendingError() == true)
  45       return false;
  46
  47    // Fork gzip
  48    int Process = fork();
  49    if (Process < 0)
  50       return _error->Errno("fork","Couldn't fork gzip");
  51
  52    // The child
  53    if (Process == 0)
  54    {
  55       dup2(From.Fd(),STDIN_FILENO);
  56       dup2(To.Fd(),STDOUT_FILENO);
  57       From.Close();
  58       To.Close();
  59       SetCloseExec(STDIN_FILENO,false);
  60       SetCloseExec(STDOUT_FILENO,false);
  61
  62       const char *Args[3];
  63       Args[0] = _config->Find("Dir::bin::gzip","gzip").c_str();
  64       Args[1] = "-d";
  65       Args[2] = 0;
  66       execvp(Args[0],(char **)Args);
  67       exit(100);
  68    }
  69    From.Close();
  70
  71    // Wait for gzip to finish
  72    int Status;
  73    if (waitpid(Process,&Status,0) != Process)
  74    {
  75       To.OpFail();
  76       return _error->Errno("wait","Waiting for gzip failed");
  77    }
  78
  79    if (WIFEXITED(Status) == 0 || WEXITSTATUS(Status) != 0)
  80    {
  81       To.OpFail();
  82       return _error->Error("gzip failed, perhaps the disk is full or the directory permissions are wrong.");
  83    }
  84
  85    To.Close();
  86
  87    // Transfer the modification times
  88    struct stat Buf;
  89    if (stat(Get.Path.c_str(),&Buf) != 0)
  90       return _error->Errno("stat","Failed to stat");
  91
  92    struct utimbuf TimeBuf;
  93    TimeBuf.actime = Buf.st_atime;
  94    TimeBuf.modtime = Buf.st_mtime;
  95    if (utime(Itm->DestFile.c_str(),&TimeBuf) != 0)
  96       return _error->Errno("utime","Failed to set modification time");
  97
  98    // Return a Done response
  99    FetchResult Res;
 100    Res.LastModified = Buf.st_mtime;
 101    Res.Filename = Itm->DestFile;
 102    URIDone(Res);
 103
 104    return true;
 105 }
 106                                                                         /*}}}*/
 107
 108 int main()
 109 {
 110    GzipMethod Mth;
 111    return Mth.Run();
 112 }