add function to build/check checksums

+ adjust .git/ permissions in adjust_dotdirs_permissions

2 files changed, 40 insertions, 1 deletions

diff --git a/.README.md b/.README.md
index 2aff8cd..ab666f9 100644
--- a/.README.md
+++ b/.README.md
@@ -16,3 +16,14 @@ of files `git clean` will delete by adding the `--dry-run` parameter.
     git branch --set-upstream-to=origin/master master
 
 The deployment should preferably take place right after you install Cygwin.
+
+`git` doesn't preserve file permissions.
+After the deployment, anyone will be able to read any of the deployed
+"dotfiles".
+To adjust the permissions so that only you can read the files, `source`
+`.bashrc` (`bash` does this automatically) and execute
+
+    adjust_dotfiles_permissions
+
+This also makes sure the directories in the repository are accessible only by
+yourself (including the `.git` directory).
diff --git a/.bashrc b/.bashrc
index d469dfa..e8ff441 100644
--- a/.bashrc
+++ b/.bashrc
@@ -212,7 +212,10 @@ adjust_dotdirs_permissions() {
   {
     git ls-files | xargs realpath | xargs dirname
     realpath .
-  } | sort | uniq | grep --fixed-strings --invert-match --line-regex "$( realpath . )" | xargs chmod 0700
+  } | sort | uniq | grep --fixed-strings --invert-match --line-regex "$( realpath . )" | xargs chmod 0700 || return $?
+  if [ -d .git ]; then
+    chmod --recursive 0700 .git || return $?
+  fi
   popd > /dev/null
 }
 
@@ -294,3 +297,28 @@ backup_repo_nwx() {
       HEAD
   done
 }
+
+list_files() {
+  local cmd='find . -type f'
+  if [ $# -gt 0 ]; then
+    cmd+="$( printf ' %q' '-(' )"
+    local ext="$1"
+    cmd+="$( printf ' -iname %q' "*.$ext" )"
+    shift
+    for ext; do
+      cmd+="$( printf ' -o -iname %q' "*.$ext" )"
+    done
+    cmd+="$( printf ' %q' '-)' )"
+  fi
+  eval "$cmd"
+}
+
+checksums_path='sha1sums.txt'
+
+update_checksums() {
+  list_files iso exe | xargs --max-lines=1 sha1sum > "$checksums_path"
+}
+
+checksums() {
+  sha1sum --check "$checksums_path"
+}