From 26446d37f171fd22144f442f2faa0b5e4132cfa4 Mon Sep 17 00:00:00 2001
From: Rob Landley <rob@landley.net>
Date: Tue, 18 Oct 2022 04:14:41 -0500
Subject: [PATCH] Tar --xform extract side.

Note: we accept --show-transformed as a NOP, it's always on. (Happy to
disable it if someone can explain why?)
---
 tests/tar.test   | 37 ++++++++++++++++++++++++++-----------
 toys/posix/tar.c |  1 +
 2 files changed, 27 insertions(+), 11 deletions(-)

diff --git a/tests/tar.test b/tests/tar.test
index de6617c3..d7b738c4 100755
--- a/tests/tar.test
+++ b/tests/tar.test
@@ -30,11 +30,6 @@ function LST()
   tar tv "$@" | sed 's/[ \t][ \t]*/ /g'
 }
 
-function LST2()
-{
-  LST | sed 's/^.* 23:31 //'
-}
-
 # Check that stored empty file is binary identical and decodes as expected.
 touch file
 testing "store file" "$TAR file | SUM 3" \
@@ -327,28 +322,30 @@ mkdir uno
 ln -s tres uno/dos
 touch uno/tres
 ln uno/tres uno/quatro
+tt() { $TAR --no-recursion uno uno/{dos,tres,quatro} "$@" | \
+  LST --show-transformed-names $XX | sed 's/^.* 23:31 //'; }
 testing 'xform S' \
-  "$TAR --no-recursion uno uno/{dos,tres,quatro} --xform 's/uno/one/S;s/dos/two/S;s/tres/three/S;s/quatro/four/S' | LST2" \
+  "tt --xform 's/uno/one/S;s/dos/two/S;s/tres/three/S;s/quatro/four/S'" \
   "one/\none/two -> tres\none/three\none/four link to one/three\n" "" ""
 
 testing 'xform flags=rh starts with all disabled' \
-  "$TAR --no-recursion uno uno/{dos,tres,quatro} --xform 's/uno/one/;flags=rh;s/dos/two/;s/tres/three/;s/quatro/four/' | LST2" \
+  "tt --xform 's/uno/one/;flags=rh;s/dos/two/;s/tres/three/;s/quatro/four/'" \
   "one/\none/two -> tres\none/three\none/four link to one/three\n" "" ""
 
 testing 'xform flags=rHhsS toggles' \
-  "$TAR --no-recursion uno uno/{dos,tres,quatro} --xform 's/uno/one/;flags=rHhsS;s/dos/two/;s/tres/three/;s/quatro/four/' | LST2" \
+  "tt --xform 's/uno/one/;flags=rHhsS;s/dos/two/;s/tres/three/;s/quatro/four/'"\
   "one/\none/two -> tres\none/three\none/four link to one/three\n" "" ""
 
 testing 'xform flags= is not a delta from previous' \
-  "$TAR --no-recursion uno uno/{dos,tres,quatro} --xform 'flags=s;flags=rh;s/uno/one/;s/dos/two/;s/tres/three/;s/quatro/four/' | LST2" \
+  "tt --xform 'flags=s;flags=rh;s/uno/one/;s/dos/two/;s/tres/three/;s/quatro/four/'" \
   "one/\none/two -> tres\none/three\none/four link to one/three\n" "" ""
 
 testing 'xform H' \
-  "$TAR --no-recursion uno uno/{dos,tres,quatro} --xform 'flags=rsH;s/uno/one/;s/dos/two/;s/tres/three/;s/quatro/four/' | LST2" \
+  "tt --xform 'flags=rsH;s/uno/one/;s/dos/two/;s/tres/three/;s/quatro/four/'" \
   "one/\none/two -> three\none/three\none/four link to uno/tres\n" "" ""
 
 testing 'xform R' \
-  "$TAR --no-recursion uno uno/{dos,tres,quatro} --xform 'flags=rshR;s/uno/one/;s/dos/two/;s/tres/three/;s/quatro/four/' | LST2" \
+  "tt --xform 'flags=rshR;s/uno/one/;s/dos/two/;s/tres/three/;s/quatro/four/'" \
   "uno/\nuno/dos -> three\nuno/tres\nuno/quatro link to one/three\n" "" ""
 
 testing "xform path" "$TAR one --xform=s@three/four/@zero@ | tar t | grep six" \
@@ -356,6 +353,24 @@ testing "xform path" "$TAR one --xform=s@three/four/@zero@ | tar t | grep six" \
 
 testing "xform trailing slash special case" \
   "$TAR --xform 's#^.+/##x' one/two/three/four/five | tar t" 'five/\nsix\n' '' ''
+
+# The quoting works because default IFS splits on whitepace not ;
+testing "xform extract all" \
+  "XX='--xform s/uno/one/;s/dos/two/;s/tres/three/;s/quatro/four/' tt" \
+  'one/\none/two -> three\none/three\none/four link to one/three\n' '' ''
+
+testing 'xform extract S' \
+  "XX='--xform s/uno/one/S;s/dos/two/S;s/tres/three/S;s/quatro/four/S' tt" \
+  "one/\none/two -> tres\none/three\none/four link to one/three\n" "" ""
+
+testing 'xform extract H' \
+  "XX='--xform flags=rs;s/uno/one/;s/dos/two/;s/tres/three/;s/quatro/four/' tt"\
+  "one/\none/two -> three\none/three\none/four link to uno/tres\n" "" ""
+
+testing 'xform extract R' \
+  "XX='--xform flags=sh;s/uno/one/;s/dos/two/;s/tres/three/;s/quatro/four/' tt"\
+  "uno/\nuno/dos -> three\nuno/tres\nuno/quatro link to one/three\n" "" ""
+
 rm -rf uno
 SKIP=0
 rm -rf one
diff --git a/toys/posix/tar.c b/toys/posix/tar.c
index 44a3b3b9..6f080689 100644
--- a/toys/posix/tar.c
+++ b/toys/posix/tar.c
@@ -802,6 +802,7 @@ static void unpack_tar(char *first)
       free(TT.hdr.name);
       TT.hdr.name = name;
     }
+    if ((i = "\0hs"[stridx("12", tar.type)+1])) xform(&TT.hdr.link_target, i);
 
     for (i = 0; i<TT.strip; i++) {
       char *s = strchr(name, '/');
-- 
2.39.2