Remove dead entries in .ninja_log and .ninja_deps while recompacting.

For .ninja_deps, remove objects that have no in-edges or whose in-edges
do not have a "deps" attribute. (This matches the behaviour of `-t
deps`).

BuildLog doesn't know about state, so let its recompact method take
delegate that decides is a path is life or not, and implement it in
NinjaMain.

1 files changed, 8 insertions, 3 deletions

diff --git a/src/ninja.cc b/src/ninja.cc
index a313ecb..298d993 100644
--- a/src/ninja.cc
+++ b/src/ninja.cc
@@ -68,7 +68,7 @@ struct Options {
 
 /// The Ninja main() loads up a series of data structures; various tools need
 /// to poke into these, so store them as fields on an object.
-struct NinjaMain {
+struct NinjaMain : public IsDead {
   NinjaMain(const char* ninja_command, const BuildConfig& config) :
       ninja_command_(ninja_command), config_(config) {}
 
@@ -137,6 +137,11 @@ struct NinjaMain {
 
   /// Dump the output requested by '-d stats'.
   void DumpMetrics();
+
+  virtual bool IsPathDead(StringPiece s) {
+    Node* n = state_.LookupNode(s);
+    return !n || !n->in_edge();
+  }
 };
 
 /// Subtools, accessible via "-t foo".
@@ -789,14 +794,14 @@ bool NinjaMain::OpenBuildLog(bool recompact_only) {
   }
 
   if (recompact_only) {
-    bool success = build_log_.Recompact(log_path, &err);
+    bool success = build_log_.Recompact(log_path, this, &err);
     if (!success)
       Error("failed recompaction: %s", err.c_str());
     return success;
   }
 
   if (!config_.dry_run) {
-    if (!build_log_.OpenForWrite(log_path, &err)) {
+    if (!build_log_.OpenForWrite(log_path, this, &err)) {
       Error("opening build log: %s", err.c_str());
       return false;
     }