patch for apt-get to support execution of programs just before and after update and install

[Admar Schoonen <admar@luon.net>]

Hello,

I've written a small patch for apt-get to allow execution of programs just
before and after 'update' and 'install', ie: just before and after it needs to
connect to the internet. This allows the user eg to automatically call pon and
poff; therefore he needs to add the following lines to apt.conf:

APT::Get
{
	Pre-Update "/usr/bin/pon";
	Post-Update "/usr/bin/poff";
	Pre-Download "/usr/bin/pon";
	Post-Download "/usr/bin/poff";
}

(Though, I use it not to connect to the internet, but to get a sources.list file
from a server, just before apt downloads packagelists.)

There is a little bug however: if apt doesn't need to download, since all
packages are in it's cache, the Pre-Download and Post-Download commands are
still executed.

This feature was inspired by the DPkg::Pre-Install-Pkgs feature.

I've created the diff with:
$ diff -u apt-get.cc apt-get.cc.with_pre_post_update_pre_post_download_patch >pre_post_update_pre_post_download-diff

You can apply it with:
$ patch <pre_post_update_pre_post_download-diff

If you have any questions or remarks about this, please send me a message (you
have to CC to me, since I'm not on this list).

cheers,
Admar Schoonen

--- apt-get.cc	Mon Sep 24 00:08:09 2001
+++ apt-get.cc.with_pre_post_update_pre_post_download_patch	Sun Sep 23 23:51:29 2001
@@ -795,6 +795,11 @@
    if (_config->FindB("APT::Get::Download-Only",false) == true)
       _system->UnLock();
    
+   // Execute pre-download
+   string PreDownloadCmnd;
+   PreDownloadCmnd=_config->Find("APT::Get::Pre-Download");
+   if (PreDownloadCmnd.c_str()!=NULL)
+      system(PreDownloadCmnd.c_str());
    // Run it
    while (1)
    {
@@ -823,6 +828,12 @@
       if (Fetcher.Run() == pkgAcquire::Failed)
 	 return false;
       
+      // Execute post-download
+      string PostDownloadCmnd;
+      PostDownloadCmnd=_config->Find("APT::Get::Post-Download");
+      if (PostDownloadCmnd.c_str()!=NULL)
+	 system(PostDownloadCmnd.c_str());
+
       // Print out errors
       bool Failed = false;
       for (pkgAcquire::ItemIterator I = Fetcher.ItemsBegin(); I != Fetcher.ItemsEnd(); I++)
@@ -1154,6 +1165,12 @@
 /* */
 bool DoUpdate(CommandLine &CmdL)
 {
+   // Execute pre-update
+   string PreUpdateCmnd;
+   PreUpdateCmnd=_config->Find("APT::Get::Pre-Update");
+   if (PreUpdateCmnd.c_str()!=NULL)
+      system(PreUpdateCmnd.c_str());
+ 
    if (CmdL.FileSize() != 1)
       return _error->Error(_("The update command takes no arguments"));
    
@@ -1212,6 +1229,11 @@
    if (Failed == true)
       return _error->Error(_("Some index files failed to download, they have been ignored, or old ones used instead."));
    
+   // Execute post-update
+   string PostUpdateCmnd;
+   PostUpdateCmnd=_config->Find("APT::Get::Post-Update");
+   if (PostUpdateCmnd.c_str()!=NULL)
+      system(PostUpdateCmnd.c_str());
    return true;
 }
 									/*}}}*/