From 46cddb8c1a393cc7d03fbd897f2504ae9f47179d Mon Sep 17 00:00:00 2001
From: Julian Andres Klode <jak@debian.org>
Date: Sat, 26 Dec 2015 15:25:33 +0100
Subject: [PATCH] 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.
---
 methods/rred.cc | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/methods/rred.cc b/methods/rred.cc
index bb801cb4e..351c1ebf9 100644
--- 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);
-- 
2.45.2