Hostname field expansion

README.md

@@ -4,34 +4,16 @@ root window (mostly I only see one window taking up the entire screen, with a
 dmenu at the top, and another dmenu at the bottom that runs conky).  I run conky
 in CLI mode only, and that's good enough for me.
 
-I pipe the output of conky through dmenu, which upates every two seconds.  I
-also have custom formatting functions (see scripts.lua in this repository).
-This ensures the output of conky has the same length, even if certain fields
-within the string change.  This is especially useful for the network bandwidth
-output, which otherwise change length every two seconds as the bandwidth usage
+I pipe the output of conky through dmenu, which upates every second.  I also
+have custom formatting functions (see scripts.lua in this repository).  This
+ensures the output of conky has the same length, even if certain fields within
+the string change.  This is especially useful for the network bandwidth output,
+which otherwise change length every two seconds as the bandwidth usage
 fluctuates between bytes (B), Kilobytes (KiB), and Megabytes (MiB).
 
-TODO:  My formatting function needs to be generalized.  Essentially, I'm
-creating a conky-specific printf function. Right now, it's split into two
-functions, with calls to the Lua string.format function.  One function takes
-only one format specifier, and the other takes two.  
+I have implemented `conky_printf`, a generalized function for printing conky
+data to the output string.  It needs more testing, as I'm sure there are edge
+cases where it doesn't work properly.  
 
-The `fmt()` function takes the format string, and expects a single numerical
-second argument.  If the format string contains any format specifiers (see `man
-sprintf` for details) that aren't numbers (e.g. `%s` for strings), fmt() will
-fail with an error.  I use this for the percentages of RAM, Swap, and CPU in
-use.
-
-The `fmt2()` function takes the format string, and expects two string arguments.
-It is not necessarily an error if either or both of the arguments are numbers,
-they will be cast to strings.  I use this function to format the bandwidth
-("Net:") display in conky, so the length of this segment doesn't shift around
-(the Unicode arrow icons for up and down bandwidth stay in the same place).  
-
-Ideally these two functions would be combined into a `"conky_printf` function,
-that could take an arbitrary format string with any number of format
-specifiers, with the requisite number of numerical or string arguments.  I know
-how to do this with the `...`/`arg`/`unpack(arg)` table specification in Lua,
-but numeric specifiers need to convert any strings passed to the function to
-numeric values instead of strings.  This is the challenging part, but should be
-doable.
+TODO:  Add color to the conky output!  That will take if statments, and text
+for dmenu to consume.

conky.conf

@@ -32,18 +32,22 @@ conky.config = {
 	no_buffers = true,
 	update_interval = 1.0,
 	uppercase = false,
-	use_spacer = 'right',
+	use_spacer = false,
     pad_percents = 3,
     short_units = false,
 };
 
 conky.text = 
 [[\
+${lua_parse printf %-20s ${nodename_short}} \
 RAM:${lua_parse printf %3.0f%% ${memperc}} \
 Swap:${lua_parse printf %3.0f%% ${swapperc}} \
 CPU:${lua_parse printf %3.0f%% ${cpu cpu0}} \
-/ ${fs_used /}/${fs_size /} \
+/ ${lua_parse printf %10s/%10s ${fs_used /} ${fs_size /}} \
 ${loadavg} \
-${top name 1} ${top pid 1} ${top cpu 1} ${top mem 1} \
+${lua_parse printf %-20s ${top name 1}} \
+${lua_parse printf %8d ${top pid 1}} \
+${lua_parse printf %3.2f ${top cpu 1}} \
+${lua_parse printf %3.2f ${top mem 1}} \
 Net: ${lua_parse printf %10s▲%10s▼ ${upspeed wlp4s0} ${downspeed wlp4s0}} \
 ]];

scripts.lua

@@ -19,7 +19,7 @@ function split_fmt(f)
                 in_spec = false
                 curr = ""
             elseif string.match(char, '[qs]') then
-                if string.match(curr, '^%%[0-9]*$') then
+                if string.match(curr, '^%%%-?[0-9]*$') then
                     curr = curr .. char
                     table.insert(ret, curr)
                     in_spec = false
@@ -28,7 +28,7 @@ function split_fmt(f)
                     io.stderr:write("Invalid format:  '" .. curr .. char .. "'\n")
                     return nil
                 end
-            elseif string.match(char, '[0-9%.]') then
+            elseif string.match(char, '[0-9%.%-]') then
                 curr = curr .. char
             elseif string.match(char, '%%') then
                 if string.match(curr, '^%%') then
@@ -105,7 +105,7 @@ function conky_printf(format, ...)
     end
     for i,fs in ipairs(formats) do
         if is_fmt_spec(fs) then -- we have a format specifier
-            if string.match(fs, '[dEefgiouXx]$') then -- we have a numeric format specifier, convert value to number
+            if string.match(fs, '[cdEefgiouXx]$') then -- we have a numeric format specifier, convert value to number
                 parsed_values[i] = tonumber(trim((parsed_values[i])))
             end
         end