+-- UI helpers
+function show_message(msg, ...)
+ print(msg:format(...));
+end
+
+function show_warning(msg, ...)
+ print(msg:format(...));
+end
+
+function show_usage(usage, desc)
+ print("Usage: ".._G.arg[0].." "..usage);
+ if desc then
+ print(" "..desc);
+ end
+end
+
+function getchar(n)
+ local stty_ret = os.execute("stty raw -echo 2>/dev/null");
+ local ok, char;
+ if stty_ret == 0 then
+ ok, char = pcall(io.read, n or 1);
+ os.execute("stty sane");
+ else
+ ok, char = pcall(io.read, "*l");
+ if ok then
+ char = char:sub(1, n or 1);
+ end
+ end
+ if ok then
+ return char;
+ end
+end
+
+function getline()
+ local ok, line = pcall(io.read, "*l");
+ if ok then
+ return line;
+ end
+end
+
+function getpass()
+ local stty_ret = os.execute("stty -echo 2>/dev/null");
+ if stty_ret ~= 0 then
+ io.write("\027[08m"); -- ANSI 'hidden' text attribute
+ end
+ local ok, pass = pcall(io.read, "*l");
+ if stty_ret == 0 then
+ os.execute("stty sane");
+ else
+ io.write("\027[00m");
+ end
+ io.write("\n");
+ if ok then
+ return pass;
+ end
+end
+
+function show_yesno(prompt)
+ io.write(prompt, " ");
+ local choice = getchar():lower();
+ io.write("\n");
+ if not choice:match("%a") then
+ choice = prompt:match("%[.-(%U).-%]$");
+ if not choice then return nil; end
+ end
+ return (choice == "y");
+end
+
+function read_password()
+ local password;
+ while true do
+ io.write("Enter new password: ");
+ password = getpass();
+ if not password then
+ show_message("No password - cancelled");
+ return;
+ end
+ io.write("Retype new password: ");
+ if getpass() ~= password then
+ if not show_yesno [=[Passwords did not match, try again? [Y/n]]=] then
+ return;
+ end
+ else
+ break;
+ end
+ end
+ return password;
+end
+
+function show_prompt(prompt)
+ io.write(prompt, " ");
+ local line = getline();
+ line = line and line:gsub("\n$","");
+ return (line and #line > 0) and line or nil;
+end
+
+-- Server control