Merge remote-tracking branch 'N-R-K/sxiv-rifle'

1 files changed, 44 insertions, 28 deletions

diff --git a/examples/rifle_sxiv.sh b/examples/rifle_sxiv.sh
index 0bdd892d..82c65f6c 100755
--- a/examples/rifle_sxiv.sh
+++ b/examples/rifle_sxiv.sh
@@ -10,39 +10,55 @@
 #
 #   mime ^image, has sxiv, X, flag f = path/to/this/script -- "$@"
 #
-# Implementation notes: this script is quite slow because of POSIX limitations
-# and portability concerns. First calling the shell function 'abspath' is
-# quicker than calling 'realpath' because it would fork a whole process, which
-# is slow. Second, we need to append a file list to sxiv, which can only be done
-# properly in two ways: arrays (which are not POSIX) or \0 sperated
-# strings. Unfortunately, assigning \0 to a variable is not POSIX either (will
-# not work in dash and others), so we cannot store the result of listfiles to a
-# variable.
+# Implementation note: the script tries to be POSIX compliant both in terms of
+# shell syntax and calls being made to external utilities, such as grep or find.
+# This makes it portable across many unix like systems, although it may not be
+# the cleanest or fastest approach.
+#
+# First, using case statement to get absolute path is quicker than calling
+# 'realpath' because it would fork a whole process, which is slow.
+#
+# Second, we need to append a file list to sxiv, which can only be done
+# properly in three ways: arrays (which are not POSIX).
+# \0 separated strings; but assigning \0 to a variable is not POSIX either
+# so we cannot store the result of listfiles to a variable.
+#
+# The third approach is to store the result to a tmpfile and using `-i` to feed
+# the list to sxiv. This is the fastest approach since we won't have to call
+# listfiles twice.
 
-if [ $# -eq 0 ]; then
-    echo "Usage: ${0##*/} PICTURES"
-    exit
-fi
 
-[ "$1" = '--' ] && shift
+TMPDIR="${TMPDIR:-/tmp}"
+tmp="$TMPDIR/sxiv_rifle_$$"
 
-abspath () {
-    case "$1" in
-        /*) printf "%s\n" "$1";;
-        *)  printf "%s\n" "$PWD/$1";;
-    esac
+listfiles () {
+    find -L "///${1%/*}" \( ! -path "///${1%/*}" -prune \) -type f -print |
+      grep -iE '\.(jpe?g|png|gif|webp|tiff|bmp)$' |
+      sort | tee "$tmp"
 }
 
-listfiles () {
-    find -L "$(dirname "$target")" -maxdepth 1 -type f -iregex \
-      '.*\(jpe?g\|bmp\|png\|gif\)$' -print0 | sort -z
+is_img () {
+    case "${1##*.}" in
+        "jpg"|"jpeg"|"png"|"gif"|"webp"|"tiff"|"bmp") return 0 ;;
+        *) return 1 ;;
+    esac
 }
 
-target="$(abspath "$1")"
-count="$(listfiles | grep -m 1 -ZznF "$target" | cut -d: -f1)"
+open_img () {
+    is_img "$1" || exit 1
+    trap 'rm -f $tmp' EXIT
+    count="$(listfiles "$1" | grep -nF "$1")"
+    if [ -n "$count" ]; then
+        sxiv -i -n "${count%%:*}" -- < "$tmp"
+    else
+        sxiv -- "$@" # fallback
+    fi
+}
 
-if [ -n "$count" ]; then
-    listfiles | xargs -0 sxiv -n "$count" --
-else
-    sxiv -- "$@" # fallback
-fi
+[ "$1" = '--' ] && shift
+case "$1" in
+    "") echo "Usage: ${0##*/} PICTURES" >&2; exit 1 ;;
+    /*) open_img "$1" ;;
+    "~"/*) open_img "$HOME/${1#"~"/}" ;;
+    *) open_img "$PWD/$1" ;;
+esac