[pacman-dev] [PATCH] alpm: Add events for creation of pacnew/pacorig files

[Olivier Brunel]

On 11/15/13 12:28, Allan McRae wrote:
> On 10/11/13 04:49, Olivier Brunel wrote:
>> Signed-off-by: Olivier Brunel <jjk at jjacky.com>
>> ---
>> Hey,
>>
>> Some background regarding this: I've written a little tool (kalu, [1]) which is
>> an upgrade notifier, and also features a GUI/frontend for the sysupgrade (-Syu)
>> operation.
>>
>> Whenever there was a pacnew installed, I would open a terminal and run vimdiff
>> on the files; I would also wonder if it wouldn't be nice to have a third file
>> featured, the "original" one (i.e. from the previous package). And so I started
>> wondering about kalu making a list of all pacnew files created during the
>> upgrade, as well as the name & version of the old package, so that I could use a
>> little script to extract the file and start the 3-way diff.
>>
>> (kalu allows to execute one or more command lines after the sysupgrade
>> completed, so this list is just a variable parsed on said cmdlines.)
>>
>> This all works well, but to make that list, kalu would have to e.g. use a regex
>> to extract the pacnew filenames from ALPM's warnings, and that's just not a very
>> good or reliable thing, especially when you know such warnings are translated.
>>
>> Hence, why adding a couple events (there's pacorig as well) in ALPM makes
>> everything much better & simpler; And knowing about such events could be useful
>> to some frontends, even though pacman obviously has no use for it (atm).
>>
>> So, I'm hoping you'd be willing to merge this.
>>
>> Thanks,
>> -j
>>
>> [1] http://jjacky.com/kalu
> 
> I agree the backend should report this to the frontend.   In fact, I
> would like the backend to be completely quiet and report everything to
> the frontend.

Not sure what you mean by "completely quiet" ? When I read that, I took
it to mean as far as the log goes (since ALPM doesn't output anything),
that you'd like for frontends to be doing all the logging...

But that goes against a recent patch[1] you committed, which does the
very opposite, and moved logging from pacman into ALPM. So I'm not sure
I understand what you mean here.


> Lets look at what your patch currently does:
> 
> alpm_pkg_t *arr[2] = { oldpkg, newpkg };
> EVENT(handle, ALPM_EVENT_PACNEW, arr, newpath);
> 
> First the passed path.  I think passing filename (e.g. /etc/pacman.conf)
> rather than newpath (e.g. /etc/pacman.conf.pacsave) is the better
> approach for that.  It requires less to output a ".pacsave" than to
> remove one.

Agreed.

> 
> Now I am not sure about the oldpkg/newpkg in an array passing.  I think
> just passing pkgname is a reasonable compromise.  I guess the frontend
> then can grab the old package version easily enough.

Well, the reason I did this was that - as explained - I wanted to have
the old version, but it makes sense to also have the new one (plus, I
felt it was also better for consistency w/ pacsave files).

This was a simple way to make sure the frontend has all correct info.
Otherwise, the frontend needs to store that event somewhere, then wait
for the next UPGRADE_DONE event to assign the version number(s) to all
"unassigned/versionless" pacnew/pacsave files. It just doesn't feel as
good/reliable.

I could have just put oldpkg, newpkg being easy enough to get if one
needs to, since it should be the currently installed one, but then
pacnew would have had oldpkg, and pacsave newpkg (since there's no
oldpkg), which I thought might not be the best re: consistency.
Although, since both don't have the same arguments either way, I'm not
sure there's consistency if any case actually.

If you're against the array passing, I'd like to use oldpkg for pacnew &
newpkg for pacsave better than just passing the pkgname.

-j

> 
> Allan


[1]
https://mailman.archlinux.org/pipermail/pacman-dev/2013-November/018166.html

> 
> 
>>
>>  lib/libalpm/add.c     |  3 +++
>>  lib/libalpm/alpm.h    | 10 +++++++++-
>>  src/pacman/callback.c |  3 +++
>>  3 files changed, 15 insertions(+), 1 deletion(-)
>>
>> diff --git a/lib/libalpm/add.c b/lib/libalpm/add.c
>> index ac4e36a..e5eca97 100644
>> --- a/lib/libalpm/add.c
>> +++ b/lib/libalpm/add.c
>> @@ -363,10 +363,12 @@ static int extract_single_file(alpm_handle_t *handle, struct archive *archive,
>>  				if(try_rename(handle, checkfile, newpath)) {
>>  					errors++;
>>  				} else {
>> +					alpm_pkg_t *arr[2] = { oldpkg, newpkg };
>>  					_alpm_log(handle, ALPM_LOG_WARNING, _("%s installed as %s\n"),
>>  							filename, newpath);
>>  					alpm_logaction(handle, ALPM_CALLER_PREFIX,
>>  							"warning: %s installed as %s\n", filename, newpath);
>> +					EVENT(handle, ALPM_EVENT_PACNEW, arr, newpath);
>>  				}
>>  
>>  				free(newpath);
>> @@ -395,6 +397,7 @@ static int extract_single_file(alpm_handle_t *handle, struct archive *archive,
>>  								_("%s saved as %s\n"), filename, newpath);
>>  						alpm_logaction(handle, ALPM_CALLER_PREFIX,
>>  								"warning: %s saved as %s\n", filename, newpath);
>> +						EVENT(handle, ALPM_EVENT_PACORIG, newpkg, newpath);
>>  					}
>>  				}
>>  
>> diff --git a/lib/libalpm/alpm.h b/lib/libalpm/alpm.h
>> index 2c8c1e6..c4f772d 100644
>> --- a/lib/libalpm/alpm.h
>> +++ b/lib/libalpm/alpm.h
>> @@ -387,7 +387,15 @@ typedef enum _alpm_event_t {
>>  	/** Downloading missing keys into keyring. */
>>  	ALPM_EVENT_KEY_DOWNLOAD_START,
>>  	/** Key downloading is finished. */
>> -	ALPM_EVENT_KEY_DOWNLOAD_DONE
>> +	ALPM_EVENT_KEY_DOWNLOAD_DONE,
>> +	/** A .pacnew file was installed
>> +	 * An array of packages (current/old one, and installed/new one) and the
>> +	 * name of the pacnew file are passed to the callback */
>> +	ALPM_EVENT_PACNEW,
>> +	/** A .pacorig file was created
>> +	 * The installed/new package and the name of the pacorig file are passed to
>> +	 * the callback */
>> +	ALPM_EVENT_PACORIG
>>  } alpm_event_t;
>>  
>>  /** Event callback */
>> diff --git a/src/pacman/callback.c b/src/pacman/callback.c
>> index 36531a2..0fc35f6 100644
>> --- a/src/pacman/callback.c
>> +++ b/src/pacman/callback.c
>> @@ -297,6 +297,9 @@ void cb_event(alpm_event_t event, void *data1, void *data2)
>>  		case ALPM_EVENT_DELTA_INTEGRITY_DONE:
>>  		case ALPM_EVENT_DELTA_PATCHES_DONE:
>>  		case ALPM_EVENT_DISKSPACE_DONE:
>> +		/* events of creation of .pacnew/.pacorig files */
>> +		case ALPM_EVENT_PACNEW:
>> +		case ALPM_EVENT_PACORIG:
>>  			/* nothing */
>>  			break;
>>  	}
>>
> 
>