implement indextargets option 'DefaultEnabled'

Some targets like Contents-udeb are special-needs targets. Shipping the
configuration snippet for them is okay, but they shouldn't be downloaded
by default. Forcing the user to enable targets by uncommenting targets
is wrong and this would still not really solve the problem completely as
even if you want to download some -udebs it will probably not be for all
sources you have enabled, so having the possibility of disabling a
target by default, but giving the user the option to enable it on a
per-source entry basis is better.

3 files changed, 13 insertions, 5 deletions

diff --git a/apt-pkg/deb/debmetaindex.cc b/apt-pkg/deb/debmetaindex.cc
index a26b94d82..08d8ef05e 100644
--- a/apt-pkg/deb/debmetaindex.cc
+++ b/apt-pkg/deb/debmetaindex.cc
@@ -145,6 +145,7 @@ static void GetIndexTargetsFor(char const * const Type, std::string const &URI,
 	 std::string const tplLongDesc = "$(SITE) " + APT_T_CONFIG_STR(flatArchive ? "flatDescription" : "Description", "");
 	 bool const IsOptional = APT_T_CONFIG_BOOL("Optional", true);
 	 bool const KeepCompressed = APT_T_CONFIG_BOOL("KeepCompressed", GzipIndex);
+	 bool const DefaultEnabled = APT_T_CONFIG_BOOL("DefaultEnabled", true);
 	 bool const UsePDiffs = APT_T_CONFIG_BOOL("PDiffs", E->UsePDiffs);
 	 std::string const CompressionTypes = APT_T_CONFIG_STR("CompressionTypes", DefCompressionTypes);
 #undef APT_T_CONFIG_BOOL
@@ -185,10 +186,8 @@ static void GetIndexTargetsFor(char const * const Type, std::string const &URI,
 	       Options.insert(std::make_pair("REPO_URI", URI));
 	       Options.insert(std::make_pair("TARGET_OF", Type));
 	       Options.insert(std::make_pair("CREATED_BY", *T));
-	       if (UsePDiffs)
-		  Options.insert(std::make_pair("PDIFFS", "yes"));
-	       else
-		  Options.insert(std::make_pair("PDIFFS", "no"));
+	       Options.insert(std::make_pair("PDIFFS", UsePDiffs ? "yes" : "no"));
+	       Options.insert(std::make_pair("DEFAULTENABLED", DefaultEnabled ? "yes" : "no"));
 	       Options.insert(std::make_pair("COMPRESSIONTYPES", CompressionTypes));
 
 	       IndexTarget Target(
@@ -736,7 +735,14 @@ class APT_HIDDEN debSLTypeDebian : public pkgSourceList::Type		/*{{{*/
       }
 
       std::vector<std::string> const alltargets = _config->FindVector(std::string("Acquire::IndexTargets::") + Name, "", true);
-      std::vector<std::string> mytargets = parsePlusMinusOptions("target", Options, alltargets);
+      std::vector<std::string> deftargets;
+      deftargets.reserve(alltargets.size());
+      std::copy_if(alltargets.begin(), alltargets.end(), std::back_inserter(deftargets), [&](std::string const &t) {
+	 std::string c = "Acquire::IndexTargets::";
+	 c.append(Name).append("::").append(t).append("::DefaultEnabled");
+	 return _config->FindB(c, true);
+      });
+      std::vector<std::string> mytargets = parsePlusMinusOptions("target", Options, deftargets);
       for (auto const &target : alltargets)
       {
 	 std::map<std::string, std::string>::const_iterator const opt = Options.find(target);
diff --git a/apt-pkg/indexfile.cc b/apt-pkg/indexfile.cc
index 775ddf712..1ed798410 100644
--- a/apt-pkg/indexfile.cc
+++ b/apt-pkg/indexfile.cc
@@ -145,6 +145,7 @@ std::string IndexTarget::Option(OptionKeys const EnumKey) const		/*{{{*/
       APT_CASE(TARGET_OF);
       APT_CASE(CREATED_BY);
       APT_CASE(PDIFFS);
+      APT_CASE(DEFAULTENABLED);
       APT_CASE(COMPRESSIONTYPES);
 #undef APT_CASE
       case FILENAME: return _config->FindDir("Dir::State::lists") + URItoFileName(URI);
diff --git a/apt-pkg/indexfile.h b/apt-pkg/indexfile.h
index 8f7e9dc05..f267247c1 100644
--- a/apt-pkg/indexfile.h
+++ b/apt-pkg/indexfile.h
@@ -87,6 +87,7 @@ class IndexTarget							/*{{{*/
       EXISTING_FILENAME,
       PDIFFS,
       COMPRESSIONTYPES,
+      DEFAULTENABLED,
    };
    std::string Option(OptionKeys const Key) const;
    bool OptionBool(OptionKeys const Key) const;