File

util/human/io.lua @ 13186:affaf6d08d26

util.datamanager: Pad list writes to avoid crossing block boundaries By padding items so that they do not cross block boundaries, it becomes eaiser to delete whole blocks with fallocate() without cutting items in half, improving efficiency of such operations. Since list stores are used for message archives, where the most common deletion operation would be of the oldest entires, at the top of the file. With this, all blocks that contain items to be removed could be deleted without needing to read, delete and write out the whole file.
author Kim Alvefur <zash@zash.se>
date Wed, 07 Jun 2023 00:39:30 +0200
parent 13068:7a75cbc4d87c
child 13199:278920294dfe
line wrap: on
line source

local array = require "prosody.util.array";
local utf8 = rawget(_G, "utf8") or require"prosody.util.encodings".utf8;
local len = utf8.len or function(s)
	local _, count = s:gsub("[%z\001-\127\194-\253][\128-\191]*", "");
	return count;
end;

local function getchar(n)
	local stty_ret = os.execute("stty raw -echo 2>/dev/null");
	local ok, char;
	if stty_ret 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

local function getline()
	local ok, line = pcall(io.read, "*l");
	if ok then
		return line;
	end
end

local function getpass()
	local stty_ret = os.execute("stty -echo 2>/dev/null");
	if not stty_ret then
		io.write("\027[08m"); -- ANSI 'hidden' text attribute
	end
	local ok, pass = pcall(io.read, "*l");
	if stty_ret then
		os.execute("stty sane");
	else
		io.write("\027[00m");
	end
	io.write("\n");
	if ok then
		return pass;
	end
end

local 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

local function read_password()
	local password;
	while true do
		io.write("Enter new password: ");
		password = getpass();
		if not password then
			print("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

local 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

local function printf(fmt, ...)
	print(fmt:format(...));
end

local function padright(s, width)
	return s..string.rep(" ", width-len(s));
end

local function padleft(s, width)
	return string.rep(" ", width-len(s))..s;
end

local pat = "[%z\001-\127\194-\253][\128-\191]*";
local function utf8_cut(s, pos)
	return s:match("^"..pat:rep(pos)) or s;
end

if utf8.len and utf8.offset then
	function utf8_cut(s, pos)
		return s:sub(1, utf8.offset(s, pos+1)-1);
	end
end

local function term_width(default)
	local env_cols = tonumber(os.getenv "COLUMNS");
	if env_cols then return env_cols; end
	local stty = io.popen("stty -a");
	if not stty then return default; end
	local result = stty:read("*a");
	if result then
		result = result:match("%f[%w]columns[ =]*(%d+)");
	end
	stty:close();
	return tonumber(result or default);
end

local function ellipsis(s, width)
	if len(s) <= width then return s; end
	if width <= 1 then return "…"; end
	return utf8_cut(s, width - 1) .. "…";
end

local function new_table(col_specs, max_width)
	max_width = max_width or term_width(80);
	local separator = " | ";

	local widths = {};
	local total_width = max_width - #separator * (#col_specs-1);
	local free_width = total_width;
	-- Calculate width of fixed-size columns
	for i = 1, #col_specs do
		local width = col_specs[i].width or "0";
		if not (type(width) == "string" and width:match("[p%%]$")) then
			local title = col_specs[i].title;
			width = math.max(tonumber(width), title and (#title+1) or 0);
			widths[i] = width;
			free_width = free_width - width;
		end
	end

	-- Calculate width of proportional columns
	local total_proportional_width = 0;
	for i = 1, #col_specs do
		if not widths[i] then
			local width_spec = col_specs[i].width:match("([%d%.]+)[p%%]");
			total_proportional_width = total_proportional_width + tonumber(width_spec);
		end
	end

	for i = 1, #col_specs do
		if not widths[i] then
			local width_spec = col_specs[i].width:match("([%d%.]+)[p%%]");
			local rel_width = tonumber(width_spec);
			widths[i] = math.floor(free_width*(rel_width/total_proportional_width));
		end
	end

	return function (row)
		local titles;
		if not row then
			titles, row = true, array.pluck(col_specs, "title", "");
		end
		local output = {};
		for i, column in ipairs(col_specs) do
			local width = widths[i];
			local v = row[not titles and column.key or i];
			if not titles and column.mapper then
				v = column.mapper(v, row, width, column);
			end
			if v == nil then
				v = column.default or "";
			else
				v = tostring(v);
			end
			if len(v) < width then
				if column.align == "right" then
					v = padleft(v, width);
				else
					v = padright(v, width);
				end
			elseif len(v) > width then
				v = (column.ellipsis or ellipsis)(v, width);
			end
			table.insert(output, v);
		end
		return table.concat(output, separator);
	end, max_width;
end

local day = 86400;
local multipliers = {
	d = day, w = day * 7, m = 31 * day, mo = 31 * day, y = 365.2425 * day;
	s = 1, mi = 60, h = 3600
};
local function parse_duration(duration_string)
	local n, m = duration_string:lower():match("(%d+)%s*([dwmy]?.?)");
	if not n then return nil; end
	return tonumber(n) * ( multipliers[m] or 1 );
end

return {
	getchar = getchar;
	getline = getline;
	getpass = getpass;
	show_yesno = show_yesno;
	read_password = read_password;
	show_prompt = show_prompt;
	printf = printf;
	padleft = padleft;
	padright = padright;
	term_width = term_width;
	ellipsis = ellipsis;
	table = new_table;
	parse_duration = parse_duration;
};