rred: Allow passing files as arguments for compressor testing

This introduces a -t mode in which the first argument is input,
the second is output and the remaining are diffs.

This allows us to test patching compressed files, which are
detected using their file extension.

diff --git a/methods/rred.cc b/methods/rred.cc
index bb801cb4e8d842430303d7edb633c80bd37ae329..351c1ebf998b597761e3707010a79c0357bdddd4 100644 (file)
--- a/methods/rred.cc
+++ b/methods/rred.cc
@@ -689,6 +689,7 @@ int main(int argc, char **argv)
 {
    int i;
    bool just_diff = true;
+   bool test = false;
    Patch patch;
 
    if (argc <= 1) {
@@ -696,7 +697,12 @@ int main(int argc, char **argv)
       return Mth.Run();
    }
 
-   if (argc > 1 && strcmp(argv[1], "-f") == 0) {
+   // Usage: rred -t input output diff ...
+   if (argc > 1 && strcmp(argv[1], "-t") == 0) {
+      just_diff = false;
+      test = true;
+      i = 4;
+   } else if (argc > 1 && strcmp(argv[1], "-f") == 0) {
       just_diff = false;
       i = 2;
    } else {
@@ -716,7 +722,13 @@ int main(int argc, char **argv)
       }
    }
 
-   if (just_diff) {
+   if (test) {
+      FileFd out, inp;
+      std::cerr << "Patching " << argv[2] << " into " << argv[3] << "\n";
+      inp.Open(argv[2], FileFd::ReadOnly,FileFd::Extension);
+      out.Open(argv[3], FileFd::WriteOnly | FileFd::Create, FileFd::Extension);
+      patch.apply_against_file(out, inp);
+   } else if (just_diff) {
       FileFd out;
       out.OpenDescriptor(STDOUT_FILENO, FileFd::WriteOnly | FileFd::Create);
       patch.write_diff(out);