only copy files if they contain troublesome characters

sh/oxo

@@ -62,7 +62,21 @@ oxo() { ### @-
             : $((fails+=1))
             printf "$bad" "oxo: skipping empty file: $f" >&2
         else
-            local kib="$(du -k "$f" | cut -f1)"
+            local g="$f"
+
+            # restrict the filepath to simple ascii characters that curl likes.
+            if [ -n "$(printf '%s' "$f" | tr -d \''0-9A-Za-z !#$%&()*+,./;=@[]^_`{}~-')" ]; then
+                # copy the user's file to a temporary path and use that instead.
+                g=/tmp/oxo
+                #printf "$warn" "oxo: special characters found: $f" >&2
+                if ! cp -p -- "$f" "$g"; then
+                    : $((fails+=1))
+                    printf "$bad" "oxo: failed to copy file: $f" >&2
+                    continue
+                fi
+            fi
+
+            local kib="$(du -k -- "$f" | cut -f1)"
 
             if [ "$kib" -gt 524288 ]; then
                 : $((fails+=1))
@@ -78,17 +92,13 @@ oxo() { ### @-
             local d=$(( b*c/8192+3*kib/16+1-32768 ))
             local r=$(( (d*-335+16384)/32768+30 ))
 
-            if ! cp -p "$f" /tmp/0x0; then
+            if ! curl -F"file=@\"$g\"" https://0x0.st; then
-                : $((fails+=1))
-                printf "$bad" "oxo: failed to copy file: $f" >&2
-            elif ! curl -F'file=@/tmp/0x0' https://0x0.st; then
                 : $((fails+=1))
                 printf "$bad" "oxo: failed to upload file: $f" >&2
             else
                 : $((succs+=1))
                 printf "$look" "oxo: expires in $r days: $f" >&2
             fi
-            #rm -f /tmp/0x0
         fi
     done
 
@@ -103,6 +113,8 @@ oxo() { ### @-
         printf "$err" "oxo: failed to upload $fails file$s" >&2
     fi
 
+    [ ! -e /tmp/oxo ] || rm /tmp/oxo
+
     return $fails
 }