[Zucchini] Introduce Imposed Ensemble Matcher.

Previously Zucchini-gen uses built-in heuristics to perform element
matching for ensemble patch generation. This CL adds an option
(accessible via the -impose parameter) to specify elements in "old"
and "new", and how they match. This allows the default heuristics to be
overridden, and enables external applications (who perhaps have better
ideas of element matching, e.g., have access to archiving programs) to
better use Zucchini to patch archives.

Zucchini-match is updated to prints the -impose command line to repeat
its results. Also, ElementMatch::ToString() is added.

Change-Id: I541b64722904c2fcd19ed75246d87e0268fbf86c
Reviewed-on: https://chromium-review.googlesource.com/1027191
Reviewed-by: Samuel Huang <huangs@chromium.org>
Reviewed-by: Greg Thompson <grt@chromium.org>
Commit-Queue: Samuel Huang <huangs@chromium.org>
Cr-Commit-Position: refs/heads/master@{#554909}
NOKEYCHECK=True
GitOrigin-RevId: 73a64ffde3f3b64df576aa1f2b5baebf7ec964ba

1 files changed, 25 insertions, 12 deletions

diff --git a/zucchini_tools.cc b/zucchini_tools.cc
index 57ff0b2..5fcf066 100644
--- a/zucchini_tools.cc
+++ b/zucchini_tools.cc
@@ -10,7 +10,7 @@
 #include <algorithm>
 #include <memory>
 #include <ostream>
-#include <string>
+#include <utility>
 
 #include "base/bind.h"
 #include "base/logging.h"
@@ -19,6 +19,7 @@
 #include "components/zucchini/element_detection.h"
 #include "components/zucchini/ensemble_matcher.h"
 #include "components/zucchini/heuristic_ensemble_matcher.h"
+#include "components/zucchini/imposed_ensemble_matcher.h"
 #include "components/zucchini/io_utils.h"
 
 namespace zucchini {
@@ -44,11 +45,10 @@ status::Code ReadReferences(ConstBufferView image,
     targets.erase(std::unique(targets.begin(), targets.end()), targets.end());
     size_t num_targets = targets.size();
 
-    out << "Type " << int(group.type_tag().value());
-    out << ": Pool=" << static_cast<uint32_t>(group.pool_tag().value());
-    out << ", width=" << group.width();
-    out << ", #locations=" << num_locations;
-    out << ", #targets=" << num_targets;
+    out << "Type " << int(group.type_tag().value())
+        << ": Pool=" << static_cast<uint32_t>(group.pool_tag().value())
+        << ", width=" << group.width() << ", #locations=" << num_locations
+        << ", #targets=" << num_targets;
     if (num_targets > 0) {
       double ratio = static_cast<double>(num_locations) / num_targets;
       out << " (ratio=" << base::StringPrintf("%.4f", ratio) << ")";
@@ -59,8 +59,8 @@ status::Code ReadReferences(ConstBufferView image,
       refs = group.GetReader(disasm.get());
 
       for (auto ref = refs->GetNext(); ref; ref = refs->GetNext()) {
-        out << "  " << AsHex<8>(ref->location);
-        out << " " << AsHex<8>(ref->target) << std::endl;
+        out << "  " << AsHex<8>(ref->location) << " " << AsHex<8>(ref->target)
+            << std::endl;
       }
     }
   }
@@ -112,14 +112,27 @@ status::Code DetectAll(ConstBufferView image,
 
 status::Code MatchAll(ConstBufferView old_image,
                       ConstBufferView new_image,
+                      std::string imposed_matches,
                       std::ostream& out) {
-  HeuristicEnsembleMatcher matcher(&out);
-  if (!matcher.RunMatch(old_image, new_image)) {
+  std::unique_ptr<EnsembleMatcher> matcher;
+  if (imposed_matches.empty()) {
+    matcher = std::make_unique<HeuristicEnsembleMatcher>(&out);
+  } else {
+    matcher =
+        std::make_unique<ImposedEnsembleMatcher>(std::move(imposed_matches));
+  }
+  if (!matcher->RunMatch(old_image, new_image)) {
     out << "RunMatch() failed.";
     return status::kStatusFatal;
   }
-  out << "Found " << matcher.matches().size() << " nontrivial matches and "
-      << matcher.num_identical() << " identical matches." << std::endl;
+  out << "Found " << matcher->matches().size() << " nontrivial matches and "
+      << matcher->num_identical() << " identical matches." << std::endl
+      << "To impose the same matches by command line, use: " << std::endl
+      << "  -impose=";
+  PrefixSep sep(",");
+  for (const ElementMatch& match : matcher->matches())
+    out << sep << match.ToString();
+  out << std::endl;
 
   return status::kStatusSuccess;
 }