[Quilt-dev] [PATCH v2] quilt refresh: Do not remove symlinks

[Jason Wessel]

Change the core behavior of quilt to by default not remove symlinks to
the patch files.  A backward compatibility option of
QUILT_RM_SYMLINKS=yes was introduced for the case where a developer
desires the symlinks are erased and replaced by files.

Historical notes:

    This is an 6 year old patch that is still actively used for the
    Yocto Project and others.

    http://lists.nongnu.org/archive/html/quilt-dev/2008-01/msg00004.html

    Revised again here:

    http://comments.gmane.org/gmane.comp.handhelds.openembedded/34224

Signed-off-by: Jason Wessel <address@hidden>
---
 quilt.quiltrc             |    4 +++
 quilt/refresh.in          |    7 +++-
 quilt/scripts/patchfns.in |    8 ++++-
 test/symlink.test         |   81 +++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 98 insertions(+), 2 deletions(-)
 create mode 100644 test/symlink.test

diff --git a/quilt.quiltrc b/quilt.quiltrc
index 58f665e..316452a 100644
--- a/quilt.quiltrc
+++ b/quilt.quiltrc
@@ -35,3 +35,7 @@ QUILT_PATCHES_PREFIX=yes
 # Use a specific editor for quilt (defaults to the value of $EDITOR before
 # sourcing this configuration file, or vi if $EDITOR wasn't set).
 #EDITOR=nedit
+
+#If your patch files are actually symlinks, this option set to yes
+#will break the symlinks should quilt update one of the files.
+#QUILT_RM_SYMLINKS=yes
diff --git a/quilt/refresh.in b/quilt/refresh.in
index 41d43a7..f39a877 100644
--- a/quilt/refresh.in
+++ b/quilt/refresh.in
@@ -324,7 +324,12 @@ if [ -e "$patch_file" ] && \
 then
        printf $"Patch %s is unchanged\n" "$(print_patch "$patch")"
 elif ( [ -z "$QUILT_BACKUP" -o ! -e "$patch_file" ] || \
-       mv "$patch_file" "$patch_file~" ) && \
+       if [ -L "$patch_file" -a "$QUILT_RM_SYMLINKS" != "yes" ] ; \
+       then \
+          cp "$patch_file" "$patch_file~"; \
+       else \
+          mv "$patch_file" "$patch_file~"; \
+       fi ) && \
      cat_to_new_file "$patch_file" < $tmp_result
 then
        if [ -n "$opt_fork" ]
diff --git a/quilt/scripts/patchfns.in b/quilt/scripts/patchfns.in
index 3fa26bb..7c7a67f 100644
--- a/quilt/scripts/patchfns.in
+++ b/quilt/scripts/patchfns.in
@@ -785,7 +785,13 @@ cat_to_new_file()
 {
        local filename="$1"
 
-       [ -e "$filename" ] && rm -f "$filename"
+       if [ -L "$filename" ]
+       then
+           [ "$QUILT_RM_SYMLINKS" = "yes" ] && rm -f "$filename"
+       elif [ -e "$filename" ]
+       then
+           rm -f "$filename"
+       fi
 
        case "$filename" in
        *.gz)
diff --git a/test/symlink.test b/test/symlink.test
new file mode 100644
index 0000000..dc83858
--- /dev/null
+++ b/test/symlink.test
@@ -0,0 +1,81 @@
+       $ mkdir patches
+
+# quilt should not remove symlinks to patch files
+       $ echo foo > foo
+       $ quilt new test.diff
+       > Patch patches/test.diff is now on top
+
+       $ quilt add foo
+       > File foo added to patch patches/test.diff
+
+       $ echo "foo changed" > foo
+       $ quilt refresh
+       > Refreshed patch patches/test.diff
+
+# Setup a symlink
+       $ mv patches/test.diff .
+       $ ln -s ../test.diff patches/test.diff
+       $ readlink patches/test.diff
+       > ../test.diff
+
+       $ echo "foo changed 2" > foo
+       $ quilt refresh
+       > Refreshed patch patches/test.diff
+
+       $ test -L patches/test.diff && echo FOUND_LINK
+       > FOUND_LINK
+
+       $ readlink patches/test.diff
+       > ../test.diff
+
+# Test the refresh --backup without a link
+       $ echo "foo changed 3" > foo
+       $ quilt refresh --backup
+       > Refreshed patch patches/test.diff
+
+       $ test -L patches/test.diff && echo FOUND_LINK
+       > FOUND_LINK
+
+       $ readlink patches/test.diff
+       > ../test.diff
+
+# Test the refresh --backup with a link
+        $ cp test.diff test.diff~
+        $ rm -f patches/test.diff~
+        $ ln -s ../test.diff~ patches/test.diff~
+       $ echo "foo changed 4" > foo
+       $ quilt refresh --backup
+       > Refreshed patch patches/test.diff
+
+       $ test -L patches/test.diff && echo FOUND_LINK
+       > FOUND_LINK
+
+       $ readlink patches/test.diff
+       > ../test.diff
+
+       $ readlink patches/test.diff~
+       > ../test.diff~
+
+# Now test that the symlinks are broken on a refresh with
+# QUILT_RM_SYMLINKS=yes
+
+       $ echo "foo changed 5" > foo
+       $ export QUILT_RM_SYMLINKS=yes
+       $ quilt refresh --backup
+       > Refreshed patch patches/test.diff
+
+       $ test -L patches/test.diff || echo NO_OLD_LINKS_HERE
+       > NO_OLD_LINKS_HERE
+
+       $ readlink patches/test.diff~
+       > ../test.diff
+
+       $ echo "foo changed 6" > foo
+       $ quilt refresh --backup
+       > Refreshed patch patches/test.diff
+
+       $ test -L patches/test.diff || echo NO_OLD_LINKS_HERE
+       > NO_OLD_LINKS_HERE
+
+       $ test -L patches/test.diff~ || echo NO_OLD_LINKS_HERE
+       > NO_OLD_LINKS_HERE
-- 
1.7.9.5