methods/gzip.cc: With FileFd now being able to read gzipped files, there

is no need for the gzip method any more to spawn an external gzip process.
Rewrite it to use FileFd directly, which makes the code a lot simpler, and
also using less memory and overhead.

debian/changelog

@@ -38,6 +38,10 @@ apt (0.7.26~exp5) UNRELEASED; urgency=low
     - Fix return value of pkgAcqFile::Custom600Headers() in the non-index
       case, to avoid returning NULL and causing crashers in callers. This also
       fixes a compiler warning.
+  * methods/gzip.cc: With FileFd now being able to read gzipped files, there
+    is no need for the gzip method any more to spawn an external gzip process.
+    Rewrite it to use FileFd directly, which makes the code a lot simpler, and
+    also using less memory and overhead.
 
  -- Christian Perrier <bubulle@debian.org>  Tue, 11 May 2010 19:52:00 +0200
 

methods/gzip.cc

@@ -23,8 +23,6 @@
 #include <apti18n.h>
 									/*}}}*/
 
-const char *Prog;
-
 class GzipMethod : public pkgAcqMethod
 {
    virtual bool Fetch(FetchItem *Itm);
@@ -43,14 +41,12 @@ bool GzipMethod::Fetch(FetchItem *Itm)
    URI Get = Itm->Uri;
    string Path = Get.Host + Get.Path; // To account for relative paths
    
-   string GzPathOption = "Dir::bin::"+string(Prog);
-
    FetchResult Res;
    Res.Filename = Itm->DestFile;
    URIStart(Res);
    
    // Open the source and destination files
-   FileFd From(Path,FileFd::ReadOnly);
+   FileFd From(Path,FileFd::ReadOnlyGzip);
 
    // if the file is empty, just rename it and return
    if(From.Size() == 0) 
@@ -59,40 +55,12 @@ bool GzipMethod::Fetch(FetchItem *Itm)
       return true;
    }
 
-   int GzOut[2];   
-   if (pipe(GzOut) < 0)
-      return _error->Errno("pipe",_("Couldn't open pipe for %s"),Prog);
-
-   // Fork gzip
-   pid_t Process = ExecFork();
-   if (Process == 0)
-   {
-      close(GzOut[0]);
-      dup2(From.Fd(),STDIN_FILENO);
-      dup2(GzOut[1],STDOUT_FILENO);
-      From.Close();
-      close(GzOut[1]);
-      SetCloseExec(STDIN_FILENO,false);
-      SetCloseExec(STDOUT_FILENO,false);
-      
-      const char *Args[3];
-      string Tmp = _config->Find(GzPathOption,Prog);
-      Args[0] = Tmp.c_str();
-      Args[1] = "-d";
-      Args[2] = 0;
-      execvp(Args[0],(char **)Args);
-      _exit(100);
-   }
-   From.Close();
-   close(GzOut[1]);
-   
-   FileFd FromGz(GzOut[0]);  // For autoclose   
    FileFd To(Itm->DestFile,FileFd::WriteEmpty);   
    To.EraseOnFailure();
    if (_error->PendingError() == true)
       return false;
    
-   // Read data from gzip, generate checksums and write
+   // Read data from source, generate checksums and write
    Hashes Hash;
    bool Failed = false;
    while (1) 
@@ -100,36 +68,23 @@ bool GzipMethod::Fetch(FetchItem *Itm)
       unsigned char Buffer[4*1024];
       unsigned long Count;
       
-      Count = read(GzOut[0],Buffer,sizeof(Buffer));
-      if (Count < 0 && errno == EINTR)
-	 continue;
-      
-      if (Count < 0)
+      if (!From.Read(Buffer,sizeof(Buffer),&Count))
       {
-	 _error->Errno("read", _("Read error from %s process"),Prog);
-	 Failed = true;
-	 break;
+	 To.OpFail();
+	 return false;
       }
-      
       if (Count == 0)
 	 break;
-      
+
       Hash.Add(Buffer,Count);
       if (To.Write(Buffer,Count) == false)
       {
 	 Failed = true;
-	 FromGz.Close();
 	 break;
       }      
    }
    
-   // Wait for gzip to finish
-   if (ExecWait(Process,_config->Find(GzPathOption,Prog).c_str(),false) == false)
-   {
-      To.OpFail();
-      return false;
-   }  
-       
+   From.Close();
    To.Close();
    
    if (Failed == true)
@@ -165,9 +120,5 @@ int main(int argc, char *argv[])
    setlocale(LC_ALL, "");
 
    GzipMethod Mth;
-
-   Prog = strrchr(argv[0],'/');
-   Prog++;
-   
    return Mth.Run();
 }