From 67070389f3752f6f23d1fb0c06bd963464aa8bca Mon Sep 17 00:00:00 2001
From: Julian Andres Klode <julian.klode@canonical.com>
Date: Thu, 22 Aug 2024 16:10:58 +0200
Subject: Implement 'Pin: source-version <foo>'

As wondered about by Paride some minutes ago.
---
 apt-pkg/policy.cc                    |  2 ++
 apt-pkg/versionmatch.cc              | 10 +++++++++-
 apt-pkg/versionmatch.h               |  2 +-
 doc/apt_preferences.5.xml            |  8 ++++++++
 test/integration/test-policy-pinning | 17 ++++++++++++++++-
 5 files changed, 36 insertions(+), 3 deletions(-)

diff --git a/apt-pkg/policy.cc b/apt-pkg/policy.cc
index b1d8e7223..5d361af1a 100644
--- a/apt-pkg/policy.cc
+++ b/apt-pkg/policy.cc
@@ -452,6 +452,8 @@ bool ReadPinFile(pkgPolicy &Plcy,string File)
       pkgVersionMatch::MatchType Type;
       if (stringcasecmp(Start,Word,"version") == 0 && Name.empty() == false)
 	 Type = pkgVersionMatch::Version;
+      else if (stringcasecmp(Start,Word,"source-version") == 0 && Name.empty() == false)
+	 Type = pkgVersionMatch::SourceVersion;
       else if (stringcasecmp(Start,Word,"release") == 0)
 	 Type = pkgVersionMatch::Release;
       else if (stringcasecmp(Start,Word,"origin") == 0)
diff --git a/apt-pkg/versionmatch.cc b/apt-pkg/versionmatch.cc
index f95232ac3..3af51e40c 100644
--- a/apt-pkg/versionmatch.cc
+++ b/apt-pkg/versionmatch.cc
@@ -42,7 +42,7 @@ pkgVersionMatch::pkgVersionMatch(string Data,MatchType Type) : Type(Type)
       return;
    
    // Cut up the version representation
-   if (Type == Version)
+   if (Type == Version || Type == SourceVersion)
    {
       if (Data.end()[-1] == '*')
       {
@@ -177,6 +177,14 @@ pkgCache::VerIterator pkgVersionMatch::Find(pkgCache::PkgIterator Pkg)
 /* */
 bool pkgVersionMatch::VersionMatches(pkgCache::VerIterator Ver)
 {
+   if (Type == SourceVersion)
+   {
+      if (MatchVer(Ver.SourceVerStr(),VerStr,VerPrefixMatch) == true)
+	 return true;
+      if (ExpressionMatches(VerStr, Ver.SourceVerStr()) == true)
+	 return true;
+      return false;
+   }
    if (Type == Version)
    {
       if (MatchVer(Ver.VerStr(),VerStr,VerPrefixMatch) == true)
diff --git a/apt-pkg/versionmatch.h b/apt-pkg/versionmatch.h
index faf1fd436..abaec08d6 100644
--- a/apt-pkg/versionmatch.h
+++ b/apt-pkg/versionmatch.h
@@ -62,7 +62,7 @@ class APT_PUBLIC pkgVersionMatch
 
    public:
 
-   enum MatchType {None = 0,Version,Release,Origin} Type;
+   enum MatchType {None = 0,Version,Release,Origin, SourceVersion} Type;
 
    bool MatchVer(const char *A,std::string B,bool Prefix) APT_PURE;
    static bool ExpressionMatches(const char *pattern, const char *string);
diff --git a/doc/apt_preferences.5.xml b/doc/apt_preferences.5.xml
index 1b38ae1c6..f166acc23 100644
--- a/doc/apt_preferences.5.xml
+++ b/doc/apt_preferences.5.xml
@@ -213,6 +213,14 @@ Package: perl
 Pin: version &good-perl;*
 Pin-Priority: 1001
 </programlisting>
+
+<simpara>Since 2.9.9, you can also pin by a source version:</simpara>
+<programlisting>
+Package: perl
+Pin: source-version &good-perl;*
+Pin-Priority: 1001
+</programlisting>
+
 </listitem>
 
 <listitem><simpara>The general form assigns a priority to all of the package versions in a
diff --git a/test/integration/test-policy-pinning b/test/integration/test-policy-pinning
index dc3192fe9..99f193930 100755
--- a/test/integration/test-policy-pinning
+++ b/test/integration/test-policy-pinning
@@ -80,8 +80,9 @@ testglobalpolicy
 
 msgmsg 'Test with specific packages'
 
+# Yeesh, the XB-Source stuff is hacky, hopefully this won't break.
 buildsimplenativepackage "coolstuff" "all" "1.0" "stable"
-buildsimplenativepackage "coolstuff" "all" "2.0~bpo1" "backports"
+buildsimplenativepackage "coolstuff" "all" "2.0~bpo1" "backports" "XB-Source: coolstuff (2.0~bpo1-source-version)"
 
 setupaptarchive
 
@@ -434,6 +435,20 @@ testsuccessequal "coolstuff:
      1.0 500
         500 file:${tmppath}/aptarchive stable/main all Packages" aptcache policy coolstuff
 
+echo "Package: coolstuff
+Pin: source-version 2.0~bpo1-source-version
+Pin-Priority: 1000" > rootdir/etc/apt/preferences
+testsuccessequal "coolstuff:
+  Installed: 2.0~bpo1
+  Candidate: 2.0~bpo1
+  Version table:
+     2.0~bpo2 100
+        100 file:${tmppath}/aptarchive backports/main all Packages
+ *** 2.0~bpo1 1000
+        100 ${tmppath}/rootdir/var/lib/dpkg/status
+     1.0 500
+        500 file:${tmppath}/aptarchive stable/main all Packages" aptcache policy coolstuff
+
 # Check for 0
 echo "Package: coolstuff
 Pin: release n=backports
-- 
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