Merge pull request #767 from mogorman/garbage_collect_keep_last_few

Implement --delete-generations + flag for keeping last N number of gens

2 files changed, 25 insertions, 0 deletions

diff --git a/src/libstore/profiles.cc b/src/libstore/profiles.cc
index 4a607b584506..4c6af567ae6f 100644
--- a/src/libstore/profiles.cc
+++ b/src/libstore/profiles.cc
@@ -157,6 +157,29 @@ void deleteGenerations(const Path & profile, const std::set<unsigned int> & gens
     }
 }
 
+void deleteGenerationsGreaterThan(const Path & profile, int max, bool dryRun)
+{
+    PathLocks lock;
+    lockProfile(lock, profile);
+
+    int curGen;
+    bool fromCurGen = false;
+    Generations gens = findGenerations(profile, curGen);
+    for (auto i = gens.rbegin(); i != gens.rend(); ++i) {
+        if (i->number == curGen) {
+            fromCurGen = true;
+            max--;
+            continue;
+        }
+        if (fromCurGen) {
+            if (max) {
+                max--;
+                continue;
+            }
+            deleteGeneration2(profile, i->number, dryRun);
+        }
+    }
+}
 
 void deleteOldGenerations(const Path & profile, bool dryRun)
 {
diff --git a/src/libstore/profiles.hh b/src/libstore/profiles.hh
index 1d4e6d3037db..5fa1533de311 100644
--- a/src/libstore/profiles.hh
+++ b/src/libstore/profiles.hh
@@ -39,6 +39,8 @@ void deleteGeneration(const Path & profile, unsigned int gen);
 
 void deleteGenerations(const Path & profile, const std::set<unsigned int> & gensToDelete, bool dryRun);
 
+void deleteGenerationsGreaterThan(const Path & profile, const int max, bool dryRun);
+
 void deleteOldGenerations(const Path & profile, bool dryRun);
 
 void deleteGenerationsOlderThan(const Path & profile, time_t t, bool dryRun);