update_checksums: don't recalculate existing

1 files changed, 31 insertions, 4 deletions

diff --git a/%HOME%/.bash_utils/distr.sh b/%HOME%/.bash_utils/distr.sh
index 06d342a..58e088a 100644
--- a/%HOME%/.bash_utils/distr.sh
+++ b/%HOME%/.bash_utils/distr.sh
@@ -7,9 +7,36 @@
 
 checksums_path='sha1sums.txt'
 
-update_checksums() {
-    sha1sum -- "$@" > "$checksums_path"
-}
+list_checksums_paths() (
+    set -o errexit -o nounset -o pipefail
+
+    if [ -f "$checksums_path" ]; then
+        local path
+        while IFS= read -r path; do
+            printf "$path"'\0'
+        done < <( sed --binary 's/^\\\?[[:alnum:]]\+ [ *]//' "$checksums_path" )
+    fi
+)
+
+update_checksums() (
+    set -o errexit -o nounset -o pipefail
+
+    local path
+
+    local -A existing
+    while IFS= read -d '' -r path; do
+        existing[$path]=1
+    done < <( list_checksums_paths )
+
+    local -a missing
+    for path in "$@"; do
+        if [ -z "${existing[$path]+x}" ]; then
+            missing+=("$path")
+        fi
+    done
+
+    sha1sum -- "${missing[@]+"${missing[@]}"}" >> "$checksums_path"
+)
 
 update_checksums_distr() (
     set -o errexit -o nounset -o pipefail
@@ -19,7 +46,7 @@ update_checksums_distr() (
 
     while IFS= read -d '' -r path; do
         paths+=("$path")
-    done < <( find . -type f -\( -iname '*.exe' -o -iname '*.iso' -\) -print0 )
+    done < <( find . -type f -\( -iname '*.exe' -o -iname '*.iso' -\) -printf '%P\0' )
 
     update_checksums "${paths[@]+"${paths[@]}"}"
 )