use local changelog from /usr/share/doc if possible

If pkgAcqChangelog is told to acquire the changelog for a version it
will check first if this version is installed on the disk and if so will
use the local changelog in /usr/share/doc (possibily/likely gz
compressed) instead of downloading the file from the web.

An option is provided to disable this, which is enabled by default for
the Ubuntu vendor as they truncate the local changelogs – and for apts
--print-uris action.

5 files changed, 60 insertions, 2 deletions

diff --git a/apt-pkg/acquire-item.cc b/apt-pkg/acquire-item.cc
index 446551cc2..2057b7287 100644
--- a/apt-pkg/acquire-item.cc
+++ b/apt-pkg/acquire-item.cc
@@ -3149,16 +3149,47 @@ void pkgAcqChangelog::Init(std::string const &DestDir, std::string const &DestFi
 									/*}}}*/
 std::string pkgAcqChangelog::URI(pkgCache::VerIterator const &Ver)	/*{{{*/
 {
+   std::string const confOnline = "Acquire::Changelogs::AlwaysOnline";
+   bool AlwaysOnline = _config->FindB(confOnline, false);
+   if (AlwaysOnline == false)
+      for (pkgCache::VerFileIterator VF = Ver.FileList(); VF.end() == false; ++VF)
+      {
+	 pkgCache::PkgFileIterator const PF = VF.File();
+	 if (PF.Flagged(pkgCache::Flag::NotSource) || PF->Release == 0)
+	    continue;
+	 pkgCache::RlsFileIterator const RF = PF.ReleaseFile();
+	 if (RF->Origin != 0 && _config->FindB(confOnline + "::Origin::" + RF.Origin(), false))
+	 {
+	    AlwaysOnline = true;
+	    break;
+	 }
+      }
+   if (AlwaysOnline == false)
+   {
+      pkgCache::PkgIterator const Pkg = Ver.ParentPkg();
+      if (Pkg->CurrentVer != 0 && Pkg.CurrentVer() == Ver)
+      {
+	 std::string const basename = std::string("/usr/share/doc/") + Pkg.Name() + "/changelog";
+	 std::string const debianname = basename + ".Debian";
+	 if (FileExists(debianname))
+	    return "copy://" + debianname;
+	 else if (FileExists(debianname + ".gz"))
+	    return "gzip://" + debianname + ".gz";
+	 else if (FileExists(basename))
+	    return "copy://" + basename;
+	 else if (FileExists(basename + ".gz"))
+	    return "gzip://" + basename + ".gz";
+      }
+   }
+
    char const * const SrcName = Ver.SourcePkgName();
    char const * const SrcVersion = Ver.SourceVerStr();
-   pkgCache::PkgFileIterator PkgFile;
    // find the first source for this version which promises a changelog
    for (pkgCache::VerFileIterator VF = Ver.FileList(); VF.end() == false; ++VF)
    {
       pkgCache::PkgFileIterator const PF = VF.File();
       if (PF.Flagged(pkgCache::Flag::NotSource) || PF->Release == 0)
 	 continue;
-      PkgFile = PF;
       pkgCache::RlsFileIterator const RF = PF.ReleaseFile();
       std::string const uri = URI(RF, PF.Component(), SrcName, SrcVersion);
       if (uri.empty())
diff --git a/apt-pkg/init.cc b/apt-pkg/init.cc
index c35477bf6..0dfb10978 100644
--- a/apt-pkg/init.cc
+++ b/apt-pkg/init.cc
@@ -120,6 +120,7 @@ bool pkgInitConfig(Configuration &Cnf)
    Cnf.CndSet("Acquire::Changelogs::URI::Origin::Tanglu", "http://metadata.tanglu.org/changelogs/@CHANGEPATH@_changelog");
    Cnf.CndSet("Acquire::Changelogs::URI::Origin::Ubuntu", "http://changelogs.ubuntu.com/changelogs/pool/@CHANGEPATH@/changelog");
    Cnf.CndSet("Acquire::Changelogs::URI::Origin::Ultimedia", "http://packages.ultimediaos.com/changelogs/pool/@CHANGEPATH@/changelog.txt");
+   Cnf.CndSet("Acquire::Changelogs::AlwaysOnline::Origin::Ubuntu", true);
 
    bool Res = true;
 
diff --git a/apt-private/private-download.cc b/apt-private/private-download.cc
index 6f672635f..89d0a50c7 100644
--- a/apt-private/private-download.cc
+++ b/apt-private/private-download.cc
@@ -246,6 +246,8 @@ bool DoChangelog(CommandLine &CmdL)
 
    bool const downOnly = _config->FindB("APT::Get::Download-Only", false);
    bool const printOnly = _config->FindB("APT::Get::Print-URIs", false);
+   if (printOnly)
+      _config->CndSet("Acquire::Changelogs::AlwaysOnline", true);
 
    aptAcquireWithTextStatus Fetcher;
    for (APT::VersionList::const_iterator Ver = verset.begin();
diff --git a/test/integration/test-apt-get-changelog b/test/integration/test-apt-get-changelog
index 01b81c737..3de1c5c5c 100755
--- a/test/integration/test-apt-get-changelog
+++ b/test/integration/test-apt-get-changelog
@@ -7,6 +7,7 @@ TESTDIR="$(readlink -f "$(dirname "$0")")"
 setupenvironment
 configarchitecture 'native'
 
+buildsimplenativepackage 'dpkg' 'native' '42' 'stable'
 buildsimplenativepackage 'foo' 'all' '1.0' 'stable'
 buildsimplenativepackage 'libbar' 'all' '1.0' 'stable'
 
@@ -105,3 +106,25 @@ testfailure test -e foo.changelog
 testequal "E: Failed to fetch http://localhost:${APTHTTPPORT}/does/not/exist/main/f/foo/foo_1.0/change.txt  Changelog unavailable for foo=1.0 (404  Not Found)
 " aptget changelog foo -qq -d -o Acquire::Changelogs::URI::Label::Testcases="http://localhost:${APTHTTPPORT}/does/not/exist/@CHANGEPATH@/change.txt"
 testfailure test -e foo.changelog
+cd ..
+
+testdpkgnotinstalled 'foo'
+testsuccessequal "'http://localhost:${APTHTTPPORT}/pool/main/f/foo/foo_1.0/changelog' foo.changelog" apt changelog foo --print-uris -o Acquire::Changelogs::AlwaysOnline=false
+testsuccessequal "'http://localhost:${APTHTTPPORT}/pool/main/f/foo/foo_1.0/changelog' foo.changelog" apt changelog foo --print-uris -o Acquire::Changelogs::AlwaysOnline=true
+
+testsuccess apt install dpkg -y
+# at this moment, we still have the Releasefile claim to be origin:ubuntu
+echo 'Acquire::Changelogs::AlwaysOnline::Origin::Ubuntu "false";' >> rootdir/etc/apt/apt.conf.d/nooriginchangelogs
+testsuccessequal "'http://localhost:${APTHTTPPORT}/pool/main/d/dpkg/dpkg_42/changelog' dpkg.changelog" apt changelog dpkg --print-uris
+testsuccessequal "'gzip:///usr/share/doc/dpkg/changelog.Debian.gz' dpkg.changelog" apt changelog dpkg --print-uris -o Acquire::Changelogs::AlwaysOnline=false
+testsuccessequal "'http://localhost:${APTHTTPPORT}/pool/main/d/dpkg/dpkg_42/changelog' dpkg.changelog" apt changelog dpkg --print-uris -o Acquire::Changelogs::AlwaysOnline=true
+testsuccessequal "'http://localhost:${APTHTTPPORT}/pool/main/d/dpkg/dpkg_42/changelog' dpkg.changelog" apt changelog dpkg --print-uris -o Acquire::Changelogs::AlwaysOnline=false -o Acquire::Changelogs::AlwaysOnline::Origin::Ubuntu=true
+testsuccessequal "'gzip:///usr/share/doc/dpkg/changelog.Debian.gz' dpkg.changelog" apt changelog dpkg --print-uris -o Acquire::Changelogs::AlwaysOnline=false -o Acquire::Changelogs::AlwaysOnline::Origin::Debian=true
+
+cd downloaded
+testsuccess apt changelog dpkg -d
+testfilestats 'dpkg.changelog' '%U:%G:%a' '=' "${TEST_DEFAULT_USER}:${TEST_DEFAULT_GROUP}:644"
+head -n 3 dpkg.changelog > dpkg.change
+testfileequal 'dpkg.change' "$(apthelper cat-file '/usr/share/doc/dpkg/changelog.Debian.gz' | head -n 3)"
+rm -f dpkg.change dpkg.changelog
+cd ..
diff --git a/vendor/ubuntu/apt.conf-01-vendor-ubuntu b/vendor/ubuntu/apt.conf-01-vendor-ubuntu
index e69de29bb..44e684710 100644
--- a/vendor/ubuntu/apt.conf-01-vendor-ubuntu
+++ b/vendor/ubuntu/apt.conf-01-vendor-ubuntu
@@ -0,0 +1 @@
+Acquire::Changelogs::AlwaysOnline "true";