Add swr(1df)

1 files changed, 65 insertions, 0 deletions

diff --git a/bin/swr b/bin/swr
new file mode 100755
index 00000000..56ab5919
--- /dev/null
+++ b/bin/swr
@@ -0,0 +1,65 @@
+#!/bin/sh
+# Transparently wrap scp(1) targets on the command line
+self=swr
+
+# Create a temporary directory with name in $td, and handle POSIX-ish traps to
+# remove it when the script exits.
+td=
+cleanup() {
+    [ -n "$td" ] && rm -fr -- "$td"
+    if [ "$1" != EXIT ] ; then
+        trap - "$1"
+        kill "-$1" "$$"
+    fi
+}
+for sig in EXIT HUP INT TERM ; do
+    # shellcheck disable=SC2064
+    trap "cleanup $sig" "$sig"
+done
+td=$(mktd "$self") || exit
+
+# Set a flag to manage resetting the positional parameters at the start of the
+# loop
+n=1
+for arg ; do
+
+    # If this is our first iteration, reset the shell parameters
+    case $n in
+        1) set -- ;;
+    esac
+
+    # Test whether this argument looks like a remote file
+    if (
+
+        # Test it contains a colon
+        case $arg in
+            *:*) ;;
+            *) exit 1 ;;
+        esac
+
+        # Test the part before the first colon has at least one character and
+        # only hostname characters
+        case ${arg%%:*} in
+            '') exit 1 ;;
+            *[!a-zA-Z0-9-.]*) exit 1 ;;
+        esac
+
+    ) ; then
+
+        # Looks like a remote file request; try to copy it into the temporary
+        # directory, bail out completely if we can't
+        dst=$td/$n
+        scp -q -- "$arg" "$dst" || exit
+        set -- "$@" "$dst"
+
+    else
+        # Just a plain old argument; stack it up
+        set -- "$@" "$arg"
+    fi
+
+    # Bump n
+    n=$((n+1))
+done
+
+# Run the command with the processed arguments
+exec "$@"