Control: tag -1 patch
On 15.08.2015 02:13, Russ Allbery wrote:
> I believe the explanation is that selecting the distribution doesn't work
> the way that you think it does. It just changes the prioritization used
> for selecting packages to install, which is then ignored by the source
> command. (I could have the details wrong; this is vague memory from
> previous discussions.)
Actually the explanation is that it's a bug (or two) in apt.
The code responsible for this behavior is [1]:
while ((Parse = SrcRecs.Find(Src.c_str(), MatchSrcOnly)) != 0)
{
const string Ver = Parse->Version();
// See if we need to look for a specific release tag
if (RelTag != "" && UserRequestedVerTag == "")
{
const string Rel = GetReleaseForSourceRecord(SrcList, Parse);
if (Rel == RelTag) /// <-- Here it compares the '-t' argument with
the release, e.g. stable/unstable.
{
Last = Parse;
Offset = Parse->Offset();
Version = Ver; /// <-- Here it can have the correct version. :-)
}
}
// Ignore all versions which doesn't fit
if (VerTag.empty() == false &&
Cache->VS().CmpVersion(VerTag, Ver) != 0) // exact match
continue;
// Newer version or an exact match? Save the hit
if (Last == 0 || Cache->VS().CmpVersion(Version,Ver) < 0) {
Last = Parse;
Offset = Parse->Offset();
Version = Ver; /// <-- But here it overwrites the found version
with any newer one. :-(
}
// was the version check above an exact match?
// If so, we don't need to look further
if (VerTag.empty() == false && (VerTag == Ver))
break;
}
To fix this problem, one can add a 'break;' at the point, where apt got
the correct version.
Then 'apt-get -t unstable source <source-pkg>' works as expected,
but 'apt-get -t sid source <source-pkg>' still doesn't work, because
apt doesn't compare with the distribution codename, e.g. jessie/sid.
That's not hard to fix either.
> It would be great if this could be fixed at some point, since it's really
> surprising UI behavior.
Attached patch fixes both problems, so hopefully the next apt release gets
this right.
Best regards,
Andreas
1:
https://anonscm.debian.org/cgit/apt/apt.git/tree/cmdline/apt-get.cc?id=990af3c952676eaa51ccd614ab2d4234693da397#n383
--- a/cmdline/apt-get.cc
+++ b/cmdline/apt-get.cc
@@ -161,7 +161,7 @@ static std::string MetaIndexFileNameOnDisk(metaIndex *metaindex)
// ---------------------------------------------------------------------
/* */
static std::string GetReleaseForSourceRecord(pkgSourceList *SrcList,
- pkgSrcRecords::Parser *Parse)
+ pkgSrcRecords::Parser *Parse, std::string &Dist)
{
// try to find release
const pkgIndexFile& CurrentIndexFile = Parse->Index();
@@ -184,6 +184,7 @@ static std::string GetReleaseForSourceRecord(pkgSourceList *SrcList,
{
indexRecords records;
records.Load(path);
+ Dist = records.GetDist();
return records.GetSuite();
}
}
@@ -387,13 +388,15 @@ static pkgSrcRecords::Parser *FindSrc(const char *Name,pkgRecords &Recs,
// See if we need to look for a specific release tag
if (RelTag != "" && UserRequestedVerTag == "")
{
- const string Rel = GetReleaseForSourceRecord(SrcList, Parse);
+ string Dist;
+ const string Rel = GetReleaseForSourceRecord(SrcList, Parse, Dist);
- if (Rel == RelTag)
+ if (Rel == RelTag || Dist == RelTag)
{
Last = Parse;
Offset = Parse->Offset();
Version = Ver;
+ break;
}
}
